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Intratester test-retest reliability of the real ear unaided response (REUR) was determined on 49 ears using the Frye 6500 real ear analyzer. Results revealed mean differences of less than 1 dB for repeat measurements at seven test frequencies between 250 and 4000 Hz. The average peak resonant frequency of the repeated measure was within 16 Hz of the initial measure. In addition, the intersubject variability of the amplitude of REUR was quite large. A range of 7 dB was found at 250 to 500 Hz with the range expanding to 15 to 20 dB at 2000 to 4000 Hz. Also, the peak resonant frequency varied between 2100-4800 Hz. These results are discussed in terms of those dispensers who use the REUR to "custom" order hearing aids.

Intratester test-retest reliability of insertion gain was determined on 28 subjects using the Frye 6500 real-ear analyzer. Results revealed mean differences of less than 1 dB for repeat measurements at six test frequencies between 250 and 4000 Hz. Also, over 80% of the repeat measures were within +/- 3 dB of the first measure. The results of this study are compared with previous studies of intratester reliability of insertion gain measures.

Postural stability is influenced by multiple sensory inputs, including visual, somatosensory, and vestibular cues. Adaptive changes in how these sensory inputs influence posture may occur in the presence of vestibular dysfunction. In this study, we simulated vestibular dysfunction in normal subjects in order to study immediate and adaptive modifications in postural control under reproducible and reversible experimental conditions. Twenty subjects (ages 20 to 35 years) were tested on a force-detecting platform; the support surface or visual surround was modulated (anterior-posterior) proportionally to body sway. Vestibular dysfunction was simulated by rotating subjects with their eyes closed at 180 degrees/second for 30 seconds, then rapidly halting rotation. Posturographic measures were obtained during the subsequent 20 seconds. Ten identical rotation trials for each subject were performed, alternating the direction of rotation, and with either the support surface or the visual surround modulated with sway in different subjects. Thus, only one sensory modality could provide Earth-stable sensory cues. Control groups were tested to assess effects of repeated alternating rotations alone, and effects of repeated posturographic trials alone. Sway was quantified by measuring peak-to-peak excursions of the center of mass. Results showed that subjects were more stable after rotation when they were provided with a stable support surface than with a stable visual surround. No subject could maintain stance without at least one Earth-stable sensory input. Improvement of mean sway scores in either group was not significant, although isolated cases did exhibit adaptive changes with improved stability over repeated trials.(ABSTRACT TRUNCATED AT 250 WORDS)

A 2-year study of 135 women using the Billings Ovulation Method as their method of family planning is reported. There were 1381 exposure cycles during the 1st year and 580 during the 2nd year. The total conception rates were 1.303 for the 1st year and 1.896 for the 2nd year. If one subtract the user failures from these rates, the biologic failure rates are 0.072 for the 1st year and 0.517 for the 2nd year. The continuation rate is 51.8%. An analysis of satisfaction levels is presented with a discussion of possible underlying emotional factors.

A study, based on the social learning theory model and designed to assess the effect of a postpartum educational program on mothers' use of infant car seats at the time of discharge was conducted. The control group consisted of data for 92 mothers obtained by recording their behavior at the time of discharge regarding their use of infant car seats and eight other related measures. The postpartum study group (90) was shown an educational slide/audio tape presentation followed by a question-and-answer period and demonstration of car seats. They were also given a shoppers' guide and a pamphlet of facts and pictures of car seats. Statistical significance was obtained on several measures.

Low-background tests of a 1 x 32 Si:Bi charge-injection-device (CID) IR detector array were carried out to evaluate its feasibility for space-based astronomical observations. Optimum performance was obtained at a temperature of 11 K. The device showed a peak responsivity of 4.4 A/W, an average noise level of ~670 electrons, and a minimum noise equivalent power of 3 x 10(-17) W/[equation] for 1-sec integration time. This sensitivity compares well with that of discrete extrinsic silicon photoconductors. The measured sensitivity, plus the apparent absence of anomalous effects, make extrinsic silicon CID arrays very promising for astronomical applications.

Post-irradiation biopsies were done on 68 patients who had received curative external beam radiation therapy for adenocarcinoma of the prostate. These patients were evaluated to determine subsequent rates of disease progression and patients survival. Mean followup was 5 years. Results revealed that 1) residual tumor present 12 months after therapy does not disappear, 2) advance in tumor grade occurred in 19 of 39 patients (49 per cent) with positive biopsies after therapy, 3) patients who had positive biopsies after therapy had a greater chance for disease progression (11 of 39 cases or 28 per cent) than patients with negative biopsies (4 of 29 cases or 14 per cent) and 4) hormonal therapy started when a positive biopsy was obtained appears to delay onset of disese progression.

The effect of two recombinant human hybrid interferons (IFNs), IFN-alpha AD (BglII) and IFN-alpha DA (BglII), on the growth cycle of Chlamydia trachomatis in a murine (McCoy) cell line was investigated. Ultrastructural analysis indicated that IFN-alpha AD inhibited the growth of chlamydia while IFN-alpha DA-treated cells did not significantly differ from the control monolayers. Treatment of the chlamydia-infected monolayers with IFN-alpha AD resulted in an inhibition in the transformation of elementary bodies to reticulate bodies with a consequent marked decrease in the number of chlamydia inclusions. Furthermore, chlamydial inclusions in the IFN-alpha AD-treated cells contained fewer and more immature chlamydial forms than the control or the IFN-alpha DA-treated cells. Secondary infection occurred in the IFN-alpha DA and in the control monolayer, but no such phenomena was detected in the IFN-alpha AD-treated McCoy cells indicating a loss of infectivity of the chlamydial organisms. From this study it can be concluded that purified recombinant human hybrid IFNs may exert an inhibitory effect on the growth cycle of C. trachomatis in a mouse cell line. This inhibition occurs primarily at the point of transformation from elementary to reticulate body.

Use-effectiveness of the Billings Ovulation Method (OM) is reported for 1139 clients from six centers who were followed for at least 24 months. Method failure rates were 1% when calculated by either Pearl formula or life table analysis. Combined method and user failure rates were 20% when calculated with the Pearl formula, and 16% at 12 months and 23% at 24 months by life table analysis. Pregnancy rates were higher for couples using OM alone, than for couples using OM in combination with additional fertility awareness methods or together with barrier methods. The difference was significant when estimated by the Pearl formula but not when analyzed by the life table. The emotional implications underlying the apparent contradiction between a desire to avoid pregnancy and the deliberate coital use of fertile days are reflected in the differences between method and user failure rates, the high client satisfaction levels reported with "user failure," and 56% continuation rate at 24 months. The will require in-depth exploration.

Fifty patients with adenocarcinoma of the prostate were treated by external supervoltage radiotherapy. Needle biopsies were obtained at timed intervals after completion of therapy. Six of 17 patients with stages A and B disease and 15 of 33 patients with stage C disease had positive biopsies. In patients biopsied more than 18 months after therapy 15 of 29 (52 per cent) had residual tumors. Of 17 patients biopsied 36 months or more after therapy 10 (59 per cent) had residual tumor. These results suggest that patients with residual tumor 18 months after therapy will not have resolution of the tumor at a future date and represent treatment failure.

We found vasoseminal vesiculography useful in staging adenocarcinoma of the prostate and in measurement of radiotherapy ports. In 12 patients who had radical prostatectomies, the histologic findings correlated well with the vasoseminal vesiculograms. Criteria for reading benign prostatic hyperplasia and prostatic carcinoma have been well established in the literature and are reviewed.

Patients with dizziness were evaluated with caloric stimulation and with dynamic platform posturography (Neurocom Equitest). The ability of these tests to detect abnormalities in patients with and without vertigo was assessed. In 159 patients, roughly a third had abnormal calorics while half experienced one or more "falls" during posturography. Calorics revealed proportionately more abnormalities in patients with vertigo, whereas posturography alone did not distinguish between patients with or without vertigo. Posturography did, however, identify abnormalities in a third of patients with normal calorics, regardless of their history of vertigo. Overall, more patients with vertigo had at least one abnormal test result (70%) compared with patients without vertigo (47%). We conclude that caloric abnormalities correlate with a history of vertigo, whereas posturographic deficits can be identified regardless of the presence of vertigo.

A simple method of reconstructing a previously removed posterior ear canal with an autogenous, bilaminar membrane is described. The resulting air-filled mastoid cavity is an anatomic extension of the middle ear cleft and is separated from the ear canal by a functional barrier that is continuous with the tympanic membrane. The acoustic characteristics of an associated tympanoplasty are not significantly altered, and many of the problems that are associated with an exteriorized cavity are avoided. In contradistinction to other methods of mastoid obliteration or reconstruction, the semitransparent nature of the soft canal wall allows inspection of the underlying cavity for residual or recurrent disease. The technique can be used to repair either a newly created cavity or a previous radical (or modified radical) mastoidectomy defect. The functional results of thirty ears reconstructed in this fashion are detailed. A variable amount of soft-wall retraction was noted postoperatively in 47% of the ears; however, the long-term functional results in these cases remain satisfactory.

The development of low-temperature narrowbandpass filters for the spectral region lambda < 50 mu using metallicmesh is discussed. Data are presented for temperatures down to 1.1 K and for a number of temperature cycles. The data show that such filters perform well at these temperatures with deterioration only occurring in limited cases.

Near-infrared images of the Venus night side show bright contrast features that move from east to west, in the direction of the cloud-top atmospheric superrotation. Recently acquired images of the Venus night side along with earlier spectroscopic observations allow identification of the mechanisms that produce these features, their level of formation, and the wind velocities at those levels. The features are detectable only at wavelengths near 1.74 and 2.3 micrometers, in narrow atmospheric windows between the CO(2) and H(2)O bands. The brightest features have brightness temperatures near 480 Kelvin, whereas the darkest features are more than 50 Kelvin cooler. Several factors suggest that this radiation is emitted by hot gases at altitudes below 35 kilometers in the Venus atmosphere. The feature contrasts are produced as this thermal radiation passes through a higher, cooler, atmospheric layer that has horizontal variations in transparency. The 6.5-day east-west rotation period of the features indicates that equatorial wind speeds are near 70 meters per second in this upper layer. Similar wind speeds have been measured by entry probes and balloons at altitudes between 50 and 55 kilometers in the middle cloud layer. The bright features indicate that there are partial clearings in this cloud deck. The presence of these clearings could decrease the efficiency of the atmospheric greenhouse that maintains the high surface temperatures on Venus.

The yield of infectious Chlamydia trachomatis was analyzed in human (HeLa) and mouse (McCoy) cell lines treated with the human interferon (IFN) subtypes IFN-alpha A and IFN-alpha D, with their hybrids [IFN-alpha AD (BglII), IFN-alpha AD (PvuII), and IFN-alpha DA (BglII)] constructed in vitro from their expression plasmids, or with IFN-beta 1 or buffy coat IFN. In HeLa cells, a significant inhibition of Chlamydia infectivity was obtained with IFN-alpha D, IFN-alpha DA (BglII), and buffy coat IFN. In McCoy cells, IFN-alpha AD (BglII) and IFN-alpha AD (PvuII) induced a strong degree of inhibition of Chlamydia infectivity. In McCoy cells, there was a correlation among the antichlamydial, antiviral, and antiproliferative activities of the different IFNs tested. In HeLa cells, however, the ability of a particular IFN subtype to inhibit Chlamydia infectivity did not always correlate with its inhibitory effects on encephalomyocarditis virus replication or with its antiproliferative activity.

Three cases of primary adenocarcinoma of the temporal bone which simulated a glomus jugulare tumor (on the basis of a thorough preoperative evaluation) are detailed. In each case, a vascular mass was seen beneath an intact tympanic membrane and angiography revealed the presence of a highly vascular mass centered on the jugular bulb. Computed tomography revealed erosive changes within the jugular fossa that were characteristic of a glomus jugulare tumor; in two cases, a significant posterior fossa extension was documented. The intraoperative findings failed to suggest a lesion different from paraganglioma in two of the cases; in the remaining case, the erosion of both bone and dura was diffuse and more suggestive of a malignant neoplasm. A discussion of the clinical behavior of adenocarcinomas of the middle ear is included in order to emphasize the importance of differentiating these lesions preoperatively from the more commonly encountered paragangliomas.

Adult and neonatal rats and neonatal pigs were gavaged with solutions of metal radionuclides to determine gastrointestinal absorption. Zinc-65 and technetium-95m were well-absorbed by both age groups; chromium-51, cadmium-109, tin-113, promethium-147, and plutonium-238 were not. The quantities of the poorly absorbed metals that were absorbed by neonates were between 4 and 100 times higher than those absorbed by adult rats. Autoradiograms prepared from the entire small intestine of the neonatal rat showed that 109Cd was retained in the duodenum. In contrast, measurements in the piglets showed much higher 109Cd retention in the ileum than in the duodenum. Autoradiograms and radiochemical measurements of 147Pm and 238Pu in both neonatal rats and swine showed the highest level of retention in the ileum. The results indicate that, for most of the metals studied, absorption from the gastrointestinal tract is substantially higher for neonatal than for adult rats.

Twenty subjects with no vestibular complaints and normal otoscopic exams were stimulated with 44 degrees C water for 5 minutes in one ear and their nystagmus was recorded by vertical and horizontal electro-oculography. Changes in vertical eye position and nystagmus inhibition were correlated during periods of mental tasking, relaxation, and voluntary eye elevation. The results showed an average of 42 degree eye depression with mental tasking during irrigation. In addition, mental arithmetic had a "releasing" effect on horizontal nystagmus. Elevation of the eyes on command, however, produced marked irregularity in the horizontal tracings, simulating inhibition. Almost every subject had an apparent vertical deflection on ENG with eye closure. These findings suggest a mechanical component to the phenomenon of inhibition as well as an active central mechanism.

With accurate, inexpensive plasma testosterone assays now available it is possible to monitor the efficacy of hormonal manipulation in the patient with adenocarcinoma of the prostate. We monitored plasma testosterone in our patients receiving diethylstilbestrol (DES) 1 mg. per day. We found no statistical difference in mean plasma testosterone between patients with adenocarcinoma of the prostate and castrated patients with prostatic carcinoma, all receiving DES, 1 mg. per day. We recommend that plasma testosterone be closely monitored in patients receiving hormonal therapy for adenocarcinoma of the prostate.

This paper describes a geometrically small NMR imaging system which has been developed and assembled within a university medical center environment. Consideration is given to the technical specifications and basic economics for the magnet system, NMR spectrometer, and computer configuration. Initial research objectives for the system are outlined which include (1) the signal-to-noise improvement potential of rotational gradient imaging, and (2) 19F tracer imaging considerations with a detailed discussion concerning the feasibility of in vivo NMR imaging of 19F-fluorodeoxyglucose (2-FDG and 3-FDG). Finally, potentially significant areas for research within the constraints of a small NMR imaging system are described.