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Minimally-invasive parathyroidectomy (MIP) appears to be changing preoperative treatment and referral patterns for sporadic, nonfamilial, non-multiple endocrine neoplasia, primary hyperparathyroidism (PHPT).The American Association of Clinical Endocrinologists membership was surveyed by mail (n=1406 members) regarding physician practices and surgical referral patterns for PHPT.Seven hundred eighty-eight respondents (56%) practiced 17.0+/-0.4 years and referred 63%+/-1% of patients with PHPT for operation. Most endocrinologists (90%) used localizing studies before surgical referral (sestamibi, ultrasound scanning, technetium/thallium scanning, magnetic resonance imaging, computed tomography). Respondents identified symptoms, calcium homeostasis, bone density, health status, age, and general anesthesia risk as the most important considerations for surgical referral. Most respondents (79%) indicated that MIP availability would increase the number of patients who were referred for operation (P.001), although most of the respondents stated that MIP would change the extent and duration of preoperative evaluations (P.001). Respondents in practice for fewer years were more likely to refer patients for MIP (P.001) and minimize preoperative evaluation (P.05). Endocrinologists who had a patient with a complication after traditional parathyroidectomy were more likely to embrace MIP (P.05).MIP availability decreases the extent and duration of preoperative evaluation while decreasing the time from diagnosis to referral. MIP also lowers the endocrinologists' surgical referral threshold for PHPT, although it emphasizes the perceived shortcomings of traditional parathyroidectomy that are held by many physicians.

Background: Operations for hyperparathyroidism (HPT) in a previously operated neck present a significant challenge and carry much higher morbidity rates than first-time operations. Our extensive experience with minimally invasive radioguided parathyroidectomy (MIRP) for first-time surgery for HPT has shown this method to be a directed approach to the offending adenoma, suggesting that the technique could be used to minimize reoperative neck surgery as well. Methods: Over an 11-month period 24 consecutive patients with primary HPT who had undergone at least one previous neck operation were referred for re-exploration. All patients underwent preoperative sestamibi scanning; 21 localized sufficiently to undergo MIRP. Results: All patients were cured after reoperation. Eighteen patients underwent MIRP under local anesthesia as outpatients; 3 MIRPs were done under general anesthesia. Average total operative time was 44 minutes, average incision length was 3.0 cm ± 0.2 cm. Nineteen of the procedures were completed without any frozen sections. There were no complications. Conclusion: MIRP is extremely effective in patients with HPT who have undergone previous neck exploration for parathyroid or thyroid disease. The technique allows for such a directed dissection that smaller incisions and local anesthesia in an outpatient setting are routine. (Surgery 1998;124:1088-93.)

The effect of a sudden increase in intraocular pressure (IOP) on Eye Bank eyes implanted with a posterior fixation keratoprosthesis PCL5 type (Lacombe) is evaluated. The IOP was artificially increased at a rate close to that observed in direct eye trauma. The critical pressure values causing aqueous humor leak and/or keratoprosthesis extrusion were compared to those found to blow up unoperated eyes. No statistical difference was found between operated and control eyes (6 pairs of eyes). This KPro type showed its efficacy for keratoprosthesis fixation.

OBJECTIVE: The purpose of this study was to evaluate the ability to transfect a murine pancreas with a human cytokine regulatory gene (interleukin-10 [IL-10]) and examine the duration of transgene expression, its effect on the normal pancreas, and its antiinflammatory effect during acute pancreatitis. SUMMARY BACKGROUND DATA: Interleukin-1beta and tumor necrosis factor-alpha are known detrimental mediators during the progression of acute pancreatitis, and blockade of either cytokine results in decreased severity of pancreatitis and improved survival. Although gene therapy has been proposed as a method to deliver protein-based therapy during a number of conditions, no means of effectively transfecting the pancreas without inducing injury has been developed. METHODS: A plasmid-human IL-10 construct (pMP6-hIL-10) complexed with cationic liposomes was administered by single intraperitoneal injection to healthy mice. Effective transfection (reverse transcriptase-polymerase chain reaction for hIL-10 mRNA), transfected cell type (in situ polymerase chain reaction for hIL-10 DNA), and the effect on the normal pancreas were determined. Additional animals were transfected to determine the effects of this regulatory gene on the severity of pancreatitis. RESULTS: Nearly 80% of all pancreatic cells expressed human DNA that was subsequently transcribed into mRNA through day 14. The transfection event had no effect on amylase, lipase, or pancreatic histologic appearance. Successful transfection could attenuate subsequently induced pancreatitis (all parameters p < 0.05). CONCLUSIONS: Transient transfection of a human IL-10 gene can be accomplished into all cell types of murine pancreata using a plasmid/ liposome vector. The DNA is effectively transcribed into intact mRNA and does not cause inflammation or acinar cell damage. Transfer of this cytokine regulatory gene decreases the severity of pancreatitis, demonstrating a benefit of gene therapy during this acute inflammatory process.

A recent case-control study in Indonesia suggested that the course of Brugian filariasis and in particular resistance to the development of elephantiasis was associated with certain HLA class II alleles. In order to see whether these data could be confirmed we conducted a similar study in another Indonesian population from South Sulawesi. We could not confirm our earlier results and therefore concluded that HLA-DR and -DQ alleles are at least not strongly associated with progression to elephantiasis in Brugian filariasis. The complete data are presented also for anthropological reference purposes.

As an alternative to the standard excimer laser used for PRK, we investigated the ablation rate at 213 nm of PMMA, and human corneas under controlled hydration.The output of a frequency-quintupled Nd:YAG laser (213 nm) was transformed into a quasi-Gaussian beam. PMMA and corneal lenticules maintained under controlled hydration were ablated until perforation was detected.The ablation rate of PMMA and cornea at 213 nm were similar to that at 193 nm when radiant exposure was below 200 mJ/cm2 and increased gradually between one and two times faster than that at 193 nm when radiant exposure was200 mJ/ cm2.PMMA and cornea ablation at 213 nm are similar to that at 193 nm and are different from that at 248 nm. The difference between PMMA and cornea ablation rates should be considered when using PMMA to test ablated diopter and smoothness for photorefractive surgery.

Tissue damage in corneal transplantation procedures was previously assessed in comparative pilot studies using vacuum-assisted metal blade trephines and a noncontact hydrogen fluoride laser trephine system. With the laser, endothelial damage was less than 20 x 30 microns at the edge of the posterior corneal perforation.In this study, a second generation vacuum-assisted Hessburg-Barron trephine was evaluated in full-thickness penetrating trephination performed in 16 rabbit eyes and eight fresh human donor eyes.We found a relatively large, 150-micrometer wide, annular zone of endothelial damage on the recipient cornea located 1.25 mm away from the trephined opening. Our study demonstrates that endothelial damage is linked to the instrument's vacuum fixation ring.With this trephine, endothelial damage may be avoided by using partial-depth trephination, filling the anterior chamber with viscoelastic and completing the procedure using a metal blade or diamond knife.

The essays in the first section of "Myth and Metaphor" center on those basic building blocks of literature out of which Frye believes literature is made. The second section examines generally the relationship between literature and mythology on one hand, and social concern and ideology on the other. Because one of the primary ends of education in Frye's view is to make people aware of their mythological conditioning, this section also includes two essays on education. The recurring theme through these writings is the social function of criticism. The essays in section three focus on literature itself - its critique of the purely analytic faculties, its relation to the visual arts, and two of its recurring metaphors (the stage and the journey). The subjects addressed in section four derive from Frye's long-standing preoccupation with the Bible. The book concludes with a group of essays in particular criticism that examine particular works by Thomas More, Castiglione, William Morris, Wagner and Joyce. Together, these essays illustrate the continuity of Frye's vision of culture.

High-performance computer graphics displays for CAD utilize the Shadow-Mask CRT (SMCRT). Factors affecting colour-display quality and ergonomics include beam-to-beam convergence, beamspot profile, resolution, brightness, mask pitch, and image linearity. This paper briefly covers the results of recent experiments on eye fatique and vision. In particular, the effects of beam-to-beam misconvergence and poor spot performance in colour displays. Extensive discussion is given on beam-to-beam misconvergence: What it is, how it is corrected in different SMCRT types, and state-of-the-art techniques for controlling it. Emphasis is given to the digital-processor based convergence system employing feedback (autoconvergence). Also included are considerations given to selection of CRT types for high-performance graphics. CRTs are available with dot, slot, or line screens. There are also inline and delta configuration electron guns. Each combination of screen and gun offers tradeoffs in quality, performance, and cost.

A comparison of three methods of stress determination using overcoring tests, earthquake focal-mechanism solutions, and fault-displacement analysis, was carried out near the epicentres of the 1968 Meckering and the 1970 Calingiri earthquakes, Western Australia. Shallow overcoring measurements (3–10 m) were made at seven sites in competent granite, along a 200-km north—south traverse through the location of the Meckering earthquake. The in situ measurements indicate a high regional compressive stress, acting about N77°E. This compares with the direction of the P-axes from the Meckering and Calingiri earthquakes of N91°E and N102°E, respectively, and east-west orientation of major principal stress deduced from observations of surface faulting. The highest maximum principal stress, 23 MPa, was measured at the site farthest north from the Meckering epicentre (~ 90 km), and the lowest, 4 MPa, was measured near the epicentre. The magnitude of the stress increases with distance away from the epicentral area at about 0.2 kPa/m. The results were corrected for drilling water temperature, thermal rock stresses, and suction pore pressure. The total correction was less than 2 MPa at most sites. Estimates of shear stress release from the fault-scarp displacements for Meckering and Calingiri were of similar magnitude (~10 MPa) to the difference between observed shear stress at sites close to and sites remote from the Meckering earthquake. As a cause of the earthquake it is proposed that the fault plane is progressively weakened by alteration or weathering, and that a small long-term fluctuation of head of ground water was the trigger. The high stress at shallow depths, the growing evidence of east—west major principal stress in most of the Australian continent, and the existence of horizontal stress higher than gravity lithostatic stress may have a common explanation, in terms of the driving forces of plate tectonics. The Australian results do not agree with the north—south orientation suggested by crude plate-drift theories in which the major stress is in the direction of the drift, and do not appear to fit with orientations from other continents, in the Richardson et al. (1976) interacting plate model which assumes a velocity-dependent plate driving force. An analysis of driving forces at diverging plate boundaries was carried out and suggests no dominant force-velocity relationship, thus forces independent of plate velocity may control the stress orientation in the plate.

Fundamental and first higher modes of the Rayleigh- and Love-wave group velocities along seven paths in Australia were jointly inverted by a controlled Monte Carlo procedure to obtain regional shear-wave velocity structures of the crust and upper mantle. Our data support the results of Gonez and Cleary which show an S-wave low velocity zone centred near 110 km depth in eastern Australia. However, the thickness-velocity contrast of the low velocity zone is significantly smaller. The crustal models for eastern Australia are characterized by upper crusts which are both thicker and have lower velocities than those in western Australia and have a less sharp crust-upper mantle boundary. The S-wave velocities for the upper mantle appear to be similar (∼ 4.55 km s −1 ) throughout the continent, with no obvious dependence on the age of cratonization or crustal thickness.

The surface waves from two medium sized (M ∼ 5.5) earthquakes in southeast Australia (1966 Mt. Hotham and 1982 Wonnangatta) were examined to determine average S-wave crustal structure for the region and the focal mechanisms of the two earthquakes. The S-wave models were determined from an analysis of the group velocities of the Rayleigh waves. For all paths a two-layer crust overlying a Moho at about 40 km is required to fit the observations. In the upper layer, down to about 25 km, the velocity gradients are very small and the S-wave velocities are in the range 3.4–3.6 km/s. In the lower crust the S-wave velocities increase gradually to about 4.6 km/s at the Moho where the velocity gradients are again very small. The region where the S-wave velocities increase significantly with depth corresponds to the region of the lower crust which generates strong seismic reflections (Mathur, 1983). The thin crust postulated beneath Bass Strait and Tasmania (Johnson, 1973) is not substantiated by these data and a crustal thickness of about 40 km is also required for this region. For the longer profiles (~ 1800 km) to the north and northwest of the earthquakes, the velocity step at the Moho is smaller than for the shorter profiles (~ 700 km). However, because the surface waves are less dispersed for the shorter profiles, the resolution is poorer and the models less reliable. For the 1982 Wonnangatta earthquake, the surface-wave synthetics from a focal mechanism similar to that obtained by Denham et al. (1985) fit the observations at five regional stations very well, and confirm the NW-SE compressive stress regime found by other workers. However, for the 1966 Mt. Hotham earthquake, the surface wave synthetics generated from the normal faulting solution, which was obtained from an analysis of P-wave first motions (Denham et al., 1985), do not agree with the Rayleigh wave-trains observed at Australian stations. Rather, the surface wave observations support a thrust fault type mechanism with the pressure axis having a similar direction to that obtained from the 1982 Wonnangatta earthquake and other earthquakes in the region.

The Wonnangatta earthquake of 21 November 1982 took place about 190 km NE of Melbourne, It was felt throughout eastern Victoria and southeastern New South Wales and the radius of perceptibility was about 195 km. Because the earthquake occurred in the middle crust (∼17 km) and the epicentral area was uninhabited, no damage could definitely be attributed to the earthquake and the highest reported intensity was VI on the Modified Mercalli Scale. The main earthquake was followed by 29 aftershocks that were large enough to be located and helped define the causative fault. The focal mechanism of the main earthquake was well constrained and the major double couple had a strike of 357°, a dip of 52° and a slip angle of 52°. This mechanism is consistent with horizontal compressive stresses acting NW‐SE in the crust, as observed from other earthquakes in the region. The magnitudes of the main earthquake were estimated to be 3.8 Ms, 4.8 mb and 5.4 ML and the seismic moment of about 6.3 x 1015 N m or 1.0 x 1017 N m, ...

Seismic investigations of the Earth's crust in the Lachlan Fold Belt of southeastern Australia, under the continent's highest mountain ranges, indicate a depth to the Moho of between 40 and 52 km, with P-wave velocities in the upper crust of 5.6–6.3 km s−1, lower crustal velocities of 6.7–7.4 km s−1, and upper mantle velocities of 8.0–8.1 km s−1. Velocity changes within the crust and at the Moho boundary are transitional rather than discontinuous. A well-defined low-velocity layer in the crust, at a depth of about 15–20 km, is evident throughout the region, and localized low-velocity layers may be present in the upper crust at shallower depths. The thickness of the upper crust increases considerably (from 26 to 35 km) along a 300 km NE-SW traverse, with the greatest thickness occurring under the highest mountains. S-wave velocities are close to 3.65 km s−1 in the upper crust and 3.9 km s−1 in the lower crust. Many previous descriptions of the orogenic evolution of southeastern Australia invoke models analogous to the tectonic processes occurring in western Pacific island arcs. The very thick crustal section interpreted in the Lachlan Fold Belt indicates that such orogenic evolution was unlikely, and that an Andean-type model is probably more appropriate. Major granitic batholiths in the Lachlan Fold Belt have a P-wave velocity of about 5.9–6.0 km s−1, compared with interspersed metamorphosed Palaeozoic sediments which have a velocity of about 6.25–6.5 km s−1. There is evidence that the thickness of the batholiths ranges from 15 to 22 km.

(1984). AN ANATOMY OF FRYE'S INFLUENCE. American Review of Canadian Studies: Vol. 14, No. 1, pp. 1-19.

The Beltana earthquake of 29 December 1983 occurred in the North Flinders Ranges, one of the most seismically active parts of South Australia. Although earthquakes in this region may be associated with a north‐south chain of diapirs, the structural relationship between the earthquake and the diapirs is not clear. The main Beltana earthquake was associated with two foreshocks and 16 aftershocks. The trend of this sequence (319 ± 4°) is consistent with the focal mechansim, which indicates a northwest‐trending left‐lateral strike‐slip fault caused by eastwest compression. The axis of maximum compression is similar to those obtained from six other South Australian earthquakes (McCue & Sutton 1979; Singh 1985). However, the trend of the sequence does not appear to relate to the surface geometry of the Beltana Diapir, which is intersected by the earthquake sequence. The main earthquake was recorded throughout the Australian continent. A least squares analysis of the first arrivals gives a Pn velocity of 8.28 ± ...

Studies were carried out on the ultrastructure of dividing mitotic nuclei in the hyphae of Puccinia striiformis Westd. The non-dividing nucleus was surrounded by a double membrane which was interrupted by scattered pores. A disc-like spindle-pole-body (SPB), and an electron dense nucleolus were also observed. The nucleolus was extruded before mitosis. Nucleolar extrusion was followed by division of the SPB into two daughter bodies which migrated to opposite poles. As mitosis progressed an intranuclear system of microfibrils was established between the daughter SPBs. Pole-to-pole and pole-to-chromosome microfibrils were observed during division. First the daughter chromatids separated, then the central region of the nucleus became constricted, and finally the daughter nuclei separated. Nucleoli re-appeared soon after the separation of daughter nuclei.

Although intensity data are essentially derived from qualitative observations they can be used to estimate basic earthquake parameters, such as hypocentres and magnitudes, particularly when instrumental observations are not available. In this study the intensity information was used from 138 earthquakes to derive relations which enable earthquake magnitudes to be determined from intensity data. The earthquakes ranged in size from ML = 1.3 to ML = 7.2 and the felt areas ranged from 8 km2 to 2.5 × 106 km2. We obtained the following results: (1) M L = 0.35(±0.12)(log R p ) 2 + 0.63(±0.41)(log R p ) + 1.87 (± 0.36) (2) M L = 0.38(±0.19)(log R IV ) 2 + 0.49(±0.66)(log R IV ) + 2.38 (± 0.57) (3) M L = 1.35(±0.34) + 0.57(±0.06)I o (4) M L = 0.024(±0.014)K 2 −0.061(±0.029)K + 1.51(±1.46) where Io is the maximum observed Modified Mercalli (MM) intensity, K the Sponheuer earthquake parameter, RP the equivalent radius of the MMIII isoseismal, RIV the equivalent radius of the MMIV isoseismal, and ML the Richter magnitude. Quadratic terms are necessary in relations (1), (2) and (4) because of the breakdown of the simple Kanai relation at distances close ( Rather surprisingly it was found that, for earthquakes smaller than ML = 6, eqns. (1) and (3) are more consistent with Richter's results for California than with those obtained by Nuttli et al. for the eastern United States. There is excellent agreement between our results and those obtained by Sibol et al. for central and eastern North America. For estimating ML, eqn. (1) is preferred because the observations have a lower rms deviation about the line of least squares fit.

Group and phase velocities for Rayleigh waves, in the period range 15–100 s, were analysed for paths crossing the Coral and Tasman Seas. We used data from 14 earthquakes recorded at the 6 World Wide Standard Stations: CTA, HNR, PMG, RIV, TAU, and WEL. By fixing the S-wave velocities at 4.65 km/s from 220 to 400 km and at 5.0 km/s for greater depths, we modelled the upper 220 km. As previous workers have found for oceanic regions, it was necessary to incorporate a significant low-velocity layer (LVL), usually centred at about 150 km, in all models. Typically the lid above the LVL has an S-wave velocity of 4.50 km/s, and the LVL a velocity of 4.25 km/s. Although the resolution of the models obtained precludes the determination of detailed Earth structure, the observations suggest that the thickness of the lid varies significantly between the “oceanic” and “plateaux” regions of Coral and Tasman Seas. It was found to be thicker beneath the Norfolk Ridge (90 km) and the Lord Howe Rise (85 km) than it ...

Summary Two large (∼ 500 t) chemical explosions, detonated in 1970 and 1971, in northern Australia each produced seismic amplitudes equivalent to about a magnitude 4½ earthquake. Arrivals from these explosions were recorded to a distance of 25° by 36 seismograph stations and provided an opportunity to measure seismic velocities over a large part of the Australian continent. A Pn velocity of 8.27±0.01 km s−1 and a crustal thickness of approxmately 40km were obtained from stations in the central and western regions of the continent. Stations to the east of the shot point give a lower Pn velocity of 8.17±0.02 km s−1 and indicate a significant difference in travel times in this direction. A change in slope of the P wave travel-time curve, to 8.85±0.08 km s−1 at a distance of 1400 km has not been observed before in Australia but corresponds to similar observations made from large explosions in North America. The S wave travel times also show a change in slope, near 1400 km, to 4.84 km s−1, but between 400 and 1400 km they indicate some complexity, not seen on the P wave curves, which may indicate a low velocity S layer in the upper mantle.

A Strong Motion Data Centre, for the collection, storage, distribution and preliminary analysis of accelerograms from the Australian and New Guinean regions, has recently been established at Canberra by the Australian Bureau of Mineral Resources. The work undertaken at the Centre is described and examples of the processing facilities available are given. Extensive use is made of computers in the analysis of the accelerograms and the plotting of the results. By December 1970 thirteen accelerographs had been obtained, by several institutions, for installation in the Australian and New Guinea regions and 24 accelerograms had been received at the Centre for analysis. The instruments located on unconsolidated material at Lae, Yonki and Panguna are currently producing about 5 accelerograms per year and the maximum ground acceleration recorded so far, of 0.12g, was obtained at Panguna, where the accelerograph is located on recent unconsolidated volcanic ash.

A brief description is given of the main structural units in the New Guinea-Solomon Islands region. It is shown how the distribution of earthquakes is related to these features. A new trend, named the Bismarck Sea seismic lineation, that consists of a line of shallow earthquakes across the Bismarck Sea, is revealed. This trend does not correspond to any known surface feature. Cross sections both parallel and perpendicular to the strike of the New Britain arc and the Solomon chain are presented. They show that the north New Guinea region of uplift is on a different trend to the island arc structure of New Britain. The zone of earthquakes associated with the arc dips to the north, whereas that associated with the zone of uplift dips to the south. This study has improved the definition of the seismic zones in the New Guinea-Solomon Islands region, and most of the features can be explained in terms of sea-floor spreading.

Intraerythrocytic multiplication of Theileria parva in vitro : an ultrastructural study. International Journal for Parasitology 16 : 223–229. Piroplasms of a Theileria parva isolate from Muguga, Kenya were maintained in short-term stationary erythrocyte cultures and the mode of multiplication studied by light and electron microscopy. Division of single piroplasms into four intraerythrocytic merozoites was observed within the first 24 h in vitro . After 8 days of cultivation, 10–20% of the parasitised erythrocytes contained quadruplet merozoite forms resulting from multiplication in vitro . Electronmicrographs showed that intraerythrocytic multiplication occurred by a schizogonous process that proceeded from the initial formation of rhoptries and electron-dense cytoplasmic plaques beneath the parasite's plasmalemmal membrane, to nuclear division and the final separation of a maximum of four differentiated merozoites. The merozoites formed by intra-erythrocytic schizogony in vitro had ultrastructural features identical to merozoites produced by intra-lymphocytic schizonts of T. parva .

The significance of mucous change in the human duodenum in a series of patients with peptic ulcer disease has been appraised. No specific correlation was demonstrated with the acid output of the stomach if the extent of the change is considered, but it was shown to be more common in the higher acid states. Electron microscopic studies confirmed the specific structure of the mucous cells of the duodenum and suggest that they arise either by transformation of Brunner9s gland cells or as a distinctive population in the crypts. It is suggested that the mucous change is a protective mechanism involved in some way as yet unknown with the healing of ulcers.