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INTERORD, a computer-interactive FORTRAN IV program for developing simple orders on a set of objects, is described. INTERORD executes in the interactive mode by presenting pairs to be judged at a remote terminal. The respondent at the terminal judges which one of the objects dominates the other. INTERORD utilizes the observed dominance relations to determine which additional relations are implied by the transitivity principle. Since pairs not implied are presented for judgment, a substantial reduction occurs in the number of judgments required in the pair comparisons procedure.

The clinical and angiographic features of 38 patients with ischemic heart disease and nonacute infarction pre-hospital ventricular fibrillation (VF) were examined as a function of their drug-free programmed electrical stimulation (PES) responses. Twenty-two patients (58%) had inducible ventricular tachycardia (VT) at drug-free PES (group I) and 16 patients (42%) did not (group II). Group I had more patients with: (1) remote infarction (22 of 22 vs 2 of 16; p < 0.01; (2) history of congestive failure (16 of 22 vs 0 of 16; p < 0.01); (3) prior cardiac arrest (11 of 22 vs 0 of 16; p < 0.01); (4) left ventricular (LV) ejection fraction < 40% (19 of 22 vs 1 of 16; p < 0.01); and (5) akinetic or dyskinetic LV wall motion (22 of 22 vs 2 of 16; p < 0.001). Group II had more patients with: (1) LV segments at “ischemic jeopardy” (16 of 16 vs 14 of 22; p < 0.01) and (2) factors suggestive of ischemia at the onset of VF (13 of 16 vs 1 of 22; p < 0.001). Inducible VT (IVT) was suppressed in 16 of the 20 group I patients surviving hospitalization while four were discharged with persistence of IVT despite therapy. At 27 ± 15 months, all four with persistent IVT had a recurrence of their arrhythmia. In the 16 group II patients, therapy was limited to antilschemic measures: coronary bypass in 12, propranolol in 3, and angioplasty in one. At 38 ± 9 months, no group II patient has had a recurrence of his arrhythmia. In patients with coronary disease and nonacute infarction VF: (1) absence of IVT at drug-free PES is a common finding; (2) patients free of IVT typically have features that implicate acute ischemia in the pathogenesis of VF; and (3) the outcome of such patients is excellent when antilschemic therapy is empioyed. IVT at drug-free PES is typically limited to patients with markers of LV dysfunction. Arrhythmogenesis in the inducible patient appears to derive from a state of chronic electrical instability caused by prior myocardial infarction.

INTERSCAL is a program for subject-computer interactive multidimensional scaling. The program analyzes subsets of judgments of similarity as they are given and picks out dimension-defining stimuli; this capability allows for a great reduction in the number of judgments. Program features and options are described.

Problems with pulmonary toxicity have emerged as a potentially limiting factor for amiodarone use. We prospectively studied 33 subjects treated with amiodarone for refractory arrhythmias. Serial clinical, radiographic and pulmonary function tests were correlated with the dose and duration of amiodarone treatment to define: a) prevalence of lung toxicity, b) subgroups of patients at particular risk for toxicity, c) potential interaction between amiodarone dose and toxicity. Considering all subjects, no significant change in lung volumes or airflow indices were noted; carbon monoxide diffusing capacity (DCO) underwent a mean reduction of 20.3 percent during treatment. Symptoms of possible pulmonary toxicity occurred in 27.3 percent of subjects. No type or degree of pretreatment cardiopulmonary dysfunction predicted lung toxicity. However, maintenance dose was correlated with toxicity; patients treated with doses of ≤400 mg per day from the start of treatment had insignificant reductions in DCO and did not develop symptoms.

This investigation sought (1) to identify perceptually homogenous respondent groups by two individual differences scaling models initially proposed by Tucker and Messick, and Carroll and Chang, (2) to reveal the significance of group percepts with respect to anticipated satisfactions and socio-economic and activity pattern characteristics of group members, and (3) to test empirically the significance of formal distinctions between the two individual differences models. The study utilized judgments about 12 transit attributes of three innovative urban, public transportation modes from a sample of 243 respondents. It was possible to specify seven perceptually homogenous groups, which were distinct in terms of a qualitative analysis of their perceptual spaces and a quantitative convergent-discriminant validity analysis predicated on the distances between pairs of attributes in their spaces. The perceptual groups were shown to have interpretable links to socio-economic and activity pattern characteristics of the respondents. In addition, it was possible to statistically account for the satisfaction ratings of the respondents by the dimensions of their corresponding spaces. Since the Tucker-Messick model was shown to derive more distinct spaces for the separate groups than the INDSCAL model of Carroll and Chang, the Tucker-Messick spaces more uniquely tied a group's percepts to its corresponding satisfactions.

While programmed electrical stimulation of the heart is useful in directing therapy in cardiac arrest survivors who exhibit inducible ventricular tachycardia (VT), controversy exists as to the risk of recurrent ventricular fibrillation (VF) and need for antiarrhythmic therapy in patients without inducible VT during drug-free control programmed stimulation studies. In this study, the clinical features and arrhythmic outcome of 43 survivors of VF without inducible VT at control programmed stimulation were examined. In 38 patients, factors that may have played a potentiating role in the genesis of VF included ischemia in 15, proarrhythmia in 18, rapid rate response to atrial fibrillation in 3 and acute alcoholism in 2. Three patients required antiarrhythmic drugs for supraventricular tachyarrhythmia and 40 patients were discharged without antiarrhythmic therapy. At 32 +/- 21 months (range 1 to 82), 37 (92%) have remained free of arrhythmic recurrence while 3 have had sustained subsequent major arrhythmic events (syncope 1 patient, VF 1, sudden cardiac death 1). Thus, survivors of VF without inducible VT at drug-free control programmed stimulation are characterized by (1) potentiating factors--often identifiable and correctable--that may be important to the genesis of VF; (2) generally low risk of arrhythmic recurrence; and (3) effective long-term management often achieved without the use of additional antiarrhythmic drugs or antitachycardia/defibrillation devices.

A patient is presented who had two paroxysmal supraventricular tachycardias, one slow and incessant and the other fast. Both paroxysmal tachycardias appeared to be atrioventricular (A-V) reentrant, with anterograde conduction by way of a normal A-V pathway. Two pathways conducting in retrograde manner were demonstrated, characterized by different conduction times (fast and slow), identical abnormal atrial activation sequence and A-V nodal-like properties (retrograde Wenckebach periodicity with rapid ventricular pacing, and depression with ouabain and propranolol). Thus, there appeared to be two anomalous A-V bundles with nodal-like properties conducting in retrograde fashion. Whether the paroxysmal tachycardia was fast or slow depended on which of these pathways was utilized. Spontaneous cure of incessant paroxysmal tachycardia was observed and coincided with unexplained total loss of ability for ventriculoatrial conduction.

In the last few decades, several writers have drawn attention to indications of the existence of science in nonliterate, Neolithic societies. One proponent of that idea is Alexander Thom, who has carried out extremely exact measurements of Neolithic stone monuments in Britain. Thom maintains that perhaps the main purpose of several megalithic monuments was to serve as astronomical observatories-that the exact sightlines they provide would make it possible to predict eclipses by observing extremely slight perturbations in the moon's movements along the horizon. Though there is little doubt that some megalithic monuments (e.g., Stonehenge) indicate solstices and extreme "lunistices," I argue that it is unlikely that the Neolithic observers went beyond that. My argument is as follows: (1) They did not need extreme accuracy; eclipses could be predicted with a fair chance of success by much simpler means. (2) Only one relevant moonrise in five or ten would be observable with the necessary accuracy. Moreover, s...

P ROARRHYTHMIA is a term used to describe the apparent paradoxical exacerbation or development of new arrhythmia by antiarrhythmic drugs. In its most liberal interpretation this would include drug-induced bradyarrhythmia as well as tachyarrhythmia and increases in complexity or frequency of asymptomatic atria1 or ventricular ectopic activity (VEA). Programmed electrical stimulation (PES) studies can also detect atria1 or ventricular proarrhythmic effects using various criteria. What is of most interest clinically, however, is the drug-related potentiation of symptomatic arrhythmia by the production of a hemodynamitally poorly tolerated tachycardia. Finally, antiarrhythmic drugs may increase the minimum energy required for defibrillation, thus rendering implantable cardioverter defibrillators or external DC cardioversion less effective. Amiodarone is a recently approved Class III antiarrhythmic agent which is capable of producing almost all of these proarrhythmic effects.

The notion, first advanced by Higgs and Jarman, that the archaeological record of the Upper Paleolithic provides evidence for animal husbandry has been bolstered by the research of several of their former students. Close examination of the evidence from southwestern France indicates, however, that, while plausible, such early forms of husbandry are not supported by the material record. It is proposed here that there is no currently acceptable evidence for animal husbandry in France before the Neolithic. It is also emphasized that the proponents of pre-Neolithic animal control have not developed the theory and method required to deal with this important issue.

(1978). Paleo-Indian Bison Drives: Feasibility Studies. Plains Anthropologist: Vol. 23, No. 82, pp. 79-83.

The authors define a readily distinguished type of small, triangular, side-rotched projectile point previously assigned to the Late Prehistoric Period of the northwestern Plains but which was thoug...

Classic Clovis, classic Folsom, and atypical fluted points from southern Saskatchewan are described. The variations in the atypical fluted points, which include three fluted Piano points, suggest that the parallel-flaked tradition was developed out of the fluted tradition in the centuries of rapid climatic shift following the retreat of the Valders ice. This development may have taken place in the region that included southern Saskatchewan.

Three point types, and the several varieties of each, make up the Small Side-notched Point System of the northern Plains. The earliest type is the Avonlea, appearing with large-scale communal bison hunting in the northern Plains early in the Christian era. The Avonlea type is replaced after ca. A.D. 700 by the Prairie Sidenotched type, which may have been derived from the Middle Woodland Besant points that were contemporary with Avonlea. The final northern Plains type of point is the Plains Side-notched, present from ca. A.D. 1300 to the historic period. It is suggested that the Avonlea point may have been brought by Athabascans, the Prairie Sidenotched may have been an Algonkian type, and the Plains Side-notched may have been of Mississippian derivation.

Anthony F. C. Wallace's concepts of cognitive maps and of culture as primarily the organization of diversity are utilized to discuss the significance of a Wisconsin burial mound group, the Hilgen Spring Park site. Department of Sociology-Anthropology Marquette University Department of Anthropology Milwaukee Public Museum

encounters many clusters of stone circles formed of small boulders placed at close intervals, resulting in rings of about seven to thirty or more feet in diameter. In a number of cases, these circles will be deeply embedded in the sod, suggesting that considerable time may have elapsed since they were first laid down. Local residents long ago adopted the name "tipi rings" for these phenomena. However, scrutiny of the writings of contemporary archeologists reveals confusion and uncertainty about the function of "tipi rings." Mulloy, for example, labels them "manifestations of unknown relationships" (1952:137); Wormington, as reported by Krieger (1956:450), considers them as having "ceremonial significance," and Wedel (1953:179) agrees with these views. Nevertheless, sufficient evidence does exist, it is here maintained, to demonstrate that these stone rings, concentrated in the Northern Plains, were actually what their popular name implies; rings of stones employed by Indians to anchor the peripheries of their skin lodges. Because my fieldwork has been limited to north-central Montana and adjacent Alberta, the data adduced for this belief come principally from that area; but the results probably apply also to similar rings in neighboring regions, particularly the Dakotas and Wyoming. Although tipi rings are classed as archeological remains, both historical and ethnological materials relate to the question of their use, and indeed prove more fruitful than excavation in clarifying the function of the rings. Consequently, what might be termed the "direct ethnological" approach has been utilized in this study. Of course, the assumption underlying this approach is that the rings are not of great antiquity in the Northern Plains;' not only the position of the circles on or near the ground surface, but the historical and ethnological data as well corroborate and justify it. Beginning with Maximilian, many explorers in the region noted the use of stones to weight the lodge covers, with heavy sods used as an alternative where rocks are not abundant. The Prince wrote of the Blackfoot camp at Fort Mc

The analysis of the bone from a bison drive in north-central Montana corroborates the implications of White's analyses of bison bone from Plains villages: the heaviest non-meaty bone was left at the kill site, the bones rich in marrow were chopped up for marrow-extraction; even when many animals were available all were thoroughly utilized by the hunters. This excavation also confirms ethnographic data on season of drives, methods of butchering, and use of arrows for killing.

A second-generation implantable pacemaker-cardioverter-defibrillator was evaluated in 200 patients with sustained ventricular tachycardia, ventricular fibrillation or prior cardiac arrest. The device permits demand ventricular pacing for bradyarrhythmias and for long QT interval or tachycardia suppression, uses programmable (3 to 30 J) energy shocks for conversion of ventricular tachycardia and ventricular fibrillation and is used with conventional pacing and defibrillation leads. Ventricular tachycardia/fibrillation recognition is based on the ventricular electrogram rate and requires reconfirmation before shock delivery. Two hundred patients (mean age 62 years, mean left ventricular ejection fraction 36%) were enrolled and followed up for 0 to 23 months (mean 12). Epicardial lead system implantation was performed with use of an anterolateral thoracotomy (38%), median sternotomy (26%) and subxiphoid (20%) or subcostal (16%) approach. Perioperative mortality rate was 5.5% (all nonarrhythmic deaths). Implant defibrillation threshold ranged from 3 to 30 J (mean 15), with initial programmed shock energy ranging from 3 to 30 J (mean 22). Ventricular tachycardia/fibrillation sensing threshold ranged from 0.7 to 1.8 mV (median 1) and the tachycardia detection interval from 288 to 416 ms (median 320). Reprogramming of implant variables was necessary for reliable electrographic sensing (54 patients), programmed shock therapy (61 patients) and tachycardia detection rate (63 patients). Device activation for potential shock delivery occurred in 111 patients (55.5%) with actual shock delivery after ventricular tachycardia/ fibrillation reconfirmation in 66 patients (33%). During follow-up study, there was a 1% arrhythmia mortality rate, 6.5% cardiac mortality rate and 10.5% total mortality rate. This study demonstrates that the programmable implantable pacemaker-cardioverter-defibrillator is effective in preventing arrhythmic death, yet reduces patient exposure to repeated shock therapy. Reprogramming is usually necessary during follow-up for optimal function.

Historically, compounds that contain gold have been used to treat conditions such as rheumatoid arthritis in humans. However, understanding of the metabolic fate of gold in biological tissues has been limited by lack of sensitive quantitative methods of analysis. We addressed this problem by developing a graphite furnace atomic absorption (GFAA) spectrophotometric method to measure trace amounts of gold. This method was validated on small samples of beef liver, kidney, and bone. The samples were digested in micro-Kjeldahl flasks with a mixture of sulfuric, perchloric, and nitric acids; the residue was treated with aqua regia and extracted into methylisobutyl ketone (MIBK); levels of gold were then measured by GFAA. All the reagents were of an ultra-pure grade and were monitored for gold content. We established that the linear range of quantitation was from 1 to 2500 ppb. Multiple extractions with MIBK were not necessary to recover all the gold, and, in most cases, use of ultra-pure acids was not necessary. A scan of the extracts by inductively coupled argon plasma atomic emission spectrophotometry revealed no appreciable concentration of elements that would be most likely to interfere with the determination of gold. Average recoveries of gold ranged from 102 to 111%, and the overall coefficient of variation was 5.5%

A graphite furnace atomic absorption spectrophotometry method was used to determine the total aluminum content of various foods found in an average American diet. The food products were ashed in platinum dishes, and the inorganic residue was fused using a sodium carbonate-sodium borate mixture. The fusion step allowed detection of all the various forms of aluminum found in food products. A L'vov platform was used in the graphite furnace to increase the sensitivity of the assay. Care was taken throughout the analysis to avoid various sources of aluminum contamination such as glass and porcelain dishes. All reagents were ultra-pure grade and were continuously monitored for aluminum content. Sodium borate used in the fusion flux mixture had previously been extracted with 8-hydroxyquinoline in chloroform to remove any aluminum present. Both raw and cooked foods were analyzed for aluminum with this method. Average recoveries of aluminum from food products ranged from 84 to 112%. The overall coefficient of variation of this method on the food products tested was 10%.

The automatic implantable cardioverter/defibrillator has become an integral part of the management of patients with life-threatening ventricular rhythm disturbances. The considerable size of the device (250 gm, 10.8 by 7.6 cm) results in protrusion from the abdominal wall, with an associated alteration in self-image in all patients. In thin patients, erosion through the skin can occur. We have devised an operation in which the generator is implanted in, and becomes part of, the chest wall. The two patients in whom this approach has been used are virtually unaware of the presence of the device. We propose this operation as an alternative to abdominal wall insertion when the latter is unsuitable for technical reasons.

TAILOR, a FORTRAN program for tailored testing, is described. The procedure for a joint ordering of persons and items with no pretesting as the basis for the tailored test is given, and a brief discussion of the computer program is included.

In July, 1956, I was requested by Harry B. Robinson, Chief Park Naturalist of Glacier National Park, to investigate 3 archaeological features reported to have been discovered in road construction through Marias Pass, along the southern boundary of Glacier Park. Boyd B. Gordon, Resident Engineer of the Bureau of Public Roads, in charge of the project, took me to the features in northwestern Montana, approximately 12 airline miles west of the Continental Divide, on Marias Pass between the Lewis Front Range and the Flathead Range. The site is situated on 2 flat benches high above the deep gorge of Crystal Creek and the floor of the Flathead River valley, about VA mile east of the juncture of the creek with the Middle Fork of the Flathead; its elevation is approximately 3600 feet, but it is surrounded by higher peaks such as Nyack Mountain, 4 miles southwest, which reaches 7760 feet.

Pre- and postoperative electrophysiologic study (EPS), intraoperative cardiac mapping, and extended endocardial resection of scar (EER) has enabled us to identify subgroups among 94 patients who have had operation to control or prevent malignant ventricular arrhythmia. Operative mortality was 8.5% and cure or prevention of ventricular arrhythmia was accomplished in 92% of survivors. Group 1: 13 patients were resuscitated from "sudden death" due to ventricular fibrillation (VF). All had exercise-induced VF and/or ventricular tachycardia (VT). Preoperative EPS revealed no inducible VT/VF. All had coronary artery disease, without evidence of myocardial infarction (MI) or ventricular wall motion abnormality; all were cured with conventional myocardial revascularization. Group 2: 65 patients had MI with residual left ventricular wall motion abnormality, usually aneurysm. The malignant arrhythmia, either sustained VT (38 patients) or VF (27 patients), was inducible by EPS but not usually by exercise, and all were refractory to medical therapy. Treatment was operative mapping, aneurysmectomy, EER, and coronary revascularization. Operative mortality was 11.9%; 90% of survivors are arrhythmia free, off drugs; 10% are now drug responsive. Group 3: 3 patients without coronary disease had VT or VF caused by endocardial sarcoidosis or operative scar from a previous congenital heart operation. Treatment was EPS, operative mapping, and excision of abnormal endocardial scar with no operative mortality. Group 4: 13 patients underwent aneurysmectomy for indication other than arrhythmia, but had preoperative ventricular irritability which was not life-threatening. Operation was aneurysmectomy, prophylactic EER, and revascularization with no mortality and no postoperative arrhythmic events. After many years of unpredictable and unsatisfactory results from various empirical surgical approaches, the operative treatment of malignant ventricular arrhythmia is now based on sound electrophysiologic principles.

In 54 patients with pre-excitation, 30 (56%) had inducible A-V re-entrant paroxysmal tachycardia. Of these 30, 20 had spontaneous paroxysmal tachycardia (four also had atrial fibrillation), four had spontaneous paroxysmal atrial fibrillation, five had a history of palpitation without arrhythmia, and one was asymptomatic. In 24 patients (44%), paroxysmal tachycardia was not inducible. Of these 24, none had documented paroxysmal tachycardia, four had atrial fibrillation, none had palpitation without arrhythmia, and 11 were asymptomatic. The incidence of documented paroxysmal tachycardia was higher in the patients with inducible tachycardia (P less than 0.001). Tachycardia induction was noted in 20 of 20 patients with spontaneous paroxysmal tachycardia, eight of 12 patients with paroxysmal atrial fibrillation, five of 14 patients with palpitation and no arrhythmia, and one of 12 asymptomatic patients. The frequency of ability to induce paroxysmal tachycardia was significantly higher in both the patients with documented spontaneous paroxysmal tachycardia and the patients with paroxysmal atrial fibrillation than in the asymptomatic group (P less than 0.01).

The observation made by Baum and associates1 and later confirmed by others,2 that in most instances sudden cardiac death is neither triggered by nor associated with acute myocardial infarction, def...

Patients with complex ventricular ectopy (greater than or equal to Lown grade III) and organic heart disease (OHD) are at increased risk for sudden cardiac death. Despite this fact, many such patients will remain free of symptomatic ventricular arrhythmia and thus are unnecessarily exposed to antiarrhythmic drug toxicity and arrhythmic potentiation. Programmed stimulation (PS) was used to direct therapy in 88 patients with asymptomatic ventricular ectopy complicating OHD. Thirty-three had inducible ventricular tachycardia (VT) and underwent treatment. The 55 patients without inducible VT (less than or equal to 6 repetitive ventricular responses) are the focus of this study. Three patients required treatment for persistent cardiac awareness. The remaining 52 have been followed for 22 months off antiarrhythmic drugs and all have remained free of subsequent major arrhythmic events. Therefore, in patients with complex ventricular ectopy, OHD, and absence of prior symptomatic ventricular arrhythmia, PS identifies patients at low risk for future disabling or life-threatening arrhythmic episodes and patients with absence of inducible VT can usually be managed without antiarrhythmic drugs.

A total of 40 patients with drug-refractory, life-threatening cardiac rhythm disturbances—ventricular tachycardia in 23 patients and ventricular fibrillation in 17 patients—underwent extended endocardial resection (EER) of scar tissue. Scarring was due to myocardial infarction in 38 patients, to previous congenital heart operation in 1 patient, and to sarcoidosis of the heart in 1. The EER procedure was directed by epicardial and endocardial mapping data whenever possible, and was usually combined with revascularization, aneurysmectomy, or, in 5 patients, mitral valve replacement. Operative mortality was 10%, incident to poor preoperative ventricular function and hemorrhage secondary to previous cardiac surgical procedures. Thirty-three of the 36 survivors (92%) are free of arrhythmia at follow-up periods ranging from 3 to 36 months (mean, 12.5 months); the arrhythmia in the remaining 3 patients is now drug controlled. Thirty-three patients had postoperative electrophysiological studies, and in 30 (91%), the arrhythmia was no longer inducible. The results of surgical treatment for ventricular tachycardia and ventricular fibrillation were similar. The results also proved satisfactory whether the EER procedure was directed by visual observation or mapping.

Our results indicate the following. 1. HRV is markedly depressed in inducible SCD survivors, a group at high risk of a subsequent episode of SCD. 2. Studies on patients who developed SCD during Holter monitoring indicate that HRV is depressed prior to SCD. 3. HRV is markedly depressed in inducible "asymptomatic ventricular ectopy" patients, with the degree of reduction paralleling that observed in inducible SCD survivors. In contrast, HRV of noninducible "asymptomatic ventricular ectopy" patients did not differ statistically from normal. 4. The findings provide additional evidence that cardiac parasympathetic function is depressed in patients prone to development of SCD and that altered autonomic function contributes to the development of electrical instability in such individuals. This accords with findings that such risk factors for sudden death as coronary artery disease, myocardial infarction, congestive failure, and hypertension all have been associated with reduced parasympathetic activity or attenuation of parasympathetically mediated reflexes. It is tempting to believe that diminished cardiac parasympathetic activity, perhaps by failing to counter excess sympathetic activity, contributes to SCD. 5. It may be inferred that HRV measurements have potential for serving as an independent predictor of inducibility in response to programmed ventricular stimulation and that they could represent a noninvasive screen for patients referred for evaluation of risk of SCD because of asymptomatic ventricular ectopy or other causes. In a larger sense, the data suggest that HRV measurements may provide information pertinent to the identification of individuals at increased risk of SCD that is independent of that provided by other risk factors. Given the human and economic stakes, further study is clearly warranted.

Historically, compounds that contain gold have been used to treat conditions such as rheumatoid arthritis in humans. However, understanding of the metabolic fate of gold in biological tissues has been limited by lack of sensitive quantitative methods of analysis. We addressed this problem by developing a graphite furnace atomic absorption (GFAA) spectrophotometric method to measure trace amounts of gold. This method was validated on small samples of beef liver, kidney, and bone. The samples were digested in micro-Kjeldahl flasks with a mixture of sulfuric, perchloric, and nitric acids; the residue was treated with aqua regia and extracted into methylisobutyl ketone (MIBK); levels of gold were then measured by GFAA. All the reagents were of an ultra-pure grade and were monitored for gold content. We established that the linear range of quantitation was from 1 to 2500 ppb. Multiple extractions with MIBK were not necessary to recover all the gold, and, in most cases, use of ultra-pure acids was not necessary. A scan of the extracts by inductively coupled argon plasma atomic emission spectrophotometry revealed no appreciable concentration of elements that would be most likely to interfere with the determination of gold. Average recoveries of gold ranged from 102 to 111%, and the overall coefficient of variation was 5.5%.

Aprindine was administered both intravenously and orally to 25 patients with ventricular tachycardia refractory to conventional antiarrhythmic agents to test the hypothesis that the response to intravenous aprindine predicts the response to oral aprindine. Ten patients had incessant ventricular tachycardia and 15 had paroxysmal sustained inducible ventricular tachycardia. Eleven patients (43 percent) had conversion to sinus rhythm with intravenous aprindine (nine with incessant and two with paroxysmal sustained ventricular tachycardia). Thirteen patients (all with paroxysmal sustained ventricular tachycardia) manifested slowing of the tachycardia without conversion, whereas in one patient with incessant ventricular tachycardia, the tachycardia became less frequent and nonsustained after intravenous aprindine. All 11 patients who had conversion to sinus rhythm with intravenous aprindine remained free of ventricular tachycardia during oral treatment with aprindine (at 2 weeks) and for a follow-up period of 2 to 38 months (mean 16 ± 13). Of the 14 patients who did not have conversion to sinus rhythm with intravenous aprindine, 12 had spontaneous or inducible ventricular tachycardia, or both, at evaluation 1 to 2 weeks after initiation of oral aprindine. In conclusion, administration of intravenous aprindine to patients with ventricular tachycardia is helpful in predicting the subsequent response to oral aprindine. In addition, the pattern of ventricular tachycardia predicted the response to aprindine; patients with incessant ventricular tachycardia tended to respond, and those with paroxysmal sustained ventricular tachycardia tended not to respond.

A graphite furnace atomic absorption spectrophotometry method was used to determine the total aluminum content of various foods found in an average American diet. The food products were ashed in platinum dishes, and the inorganic residue was fused using a sodium carbonate-sodium borate mixture. The fusion step allowed detection of all the various forms of aluminum found in food products. A L'vov platform was used in the graphite furnace to increase the sensitivity of the assay. Care was taken throughout the analysis to avoid various sources of aluminum contamination such as glass and porcelain dishes. All reagents were ultra-pure grade and were continuously monitored for aluminum content. Sodium borate used in the fusion flux mixture had previously been extracted with 8-hydroxyquinoline in chloroform to remove any aluminum present. Both raw and cooked foods were analyzed for aluminum with this method. Average recoveries of aluminum from food products ranged from 84 to 112%. The overall coefficient of variation of this method on the food products tested was 10%.