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61.
PB Imrey LA Jackson PH Ludwinski AC England GA Fella BC Fox LB Isdale MW Reeves JD Wenger 《Canadian Metallurgical Quarterly》1996,143(6):624-630
Between February 1991 and April 1992, eight undergraduates at a US residential university and one at a nearby 2-year college contracted serogroup C meningococcal disease. A case-control investigation with 20 controls per case, oropharyngeal carriage surveys, and multilocus enzyme electrophoresis (MEE) of serogroup C isolates were used to identify factors contributing to the outbreak. All eight sterile-site isolates from cases were closely related by MEE and were similar (though not identical) to the strain associated with the 1991-1992 epidemic of meningococcal disease in eastern Canada. Disease was associated with cigarette smoking (p = 0.012), recent patronage of campus-area bars (p = 0.034), estimated amount of time spent in campus-area bars (p = 0.0003), and, especially, recent patronage of one specific bar, bar A (p = 0.0006; odds ratio = 23.1, 95% confidence interval 3.0-571.5). In carriage surveys, 1,528 throat cultures taken from (primarily student) noncases yielded only five (0.3%) strains that were identical by MEE to those from cases. Two of these were found among 22 cultures obtained from bar A employees in spring 1992. Some cases in this outbreak may have followed transmission of the epidemic strain in bar A. Campus bar environments may facilitate the spread of meningococcal disease among teenagers and young adults. 相似文献
62.
RA Malik S Tesfaye SD Thompson A Veves AK Sharma AJ Boulton JD Ward 《Canadian Metallurgical Quarterly》1993,36(5):454-459
Twenty diabetic patients with neuropathy underwent clinical and neurophysiological evaluation together with a detailed morphometric assessment of capillary pathology in endoneurial and epineurial microvascular beds of the sural nerve. Morphological data were compared with ten non-diabetic control subjects. There were no significant differences in control subjects between basement membrane area, endothelial cell area, endothelial cell profile number or luminal area of endoneurial when compared with epineurial capillaries. In contrast, when compared with epineurial capillaries, endoneurial capillaries from diabetic patients demonstrated a significant increase in basement membrane (p < 0.001) and endothelial cell (p < 0.001) area and a significant reduction in luminal area (p < 0.001). There was no significant difference in endothelial cell profile number between endoneurial and epineurial capillaries amongst diabetic patients. Previous studies have demonstrated a good correlation between the degree of microangiopathy and measures of neuropathic severity. In the present study increased endoneurial capillary basement membrane area was significantly related to reduced peroneal nerve conduction velocity (p < 0.001), myelinated fibre density (p < 0.001) and elevated vibration (p < 0.05) and thermal (p < 0.001) perception. Increased endothelial cell area and reduced luminal size were related to a reduced peroneal nerve conduction (p < 0.05, p < 0.01, respectively), reduced myelinated fibre density (p < 0.05, p < 0.01) and elevated thermal perception (p < 0.05, p < 0.001). Epineurial capillary basement membrane, endothelial cell and luminal area failed to relate to measures of neuropathic severity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
63.
MH Thornton DB Johns JD Campeau F Hoehler GS DiZerega 《Canadian Metallurgical Quarterly》1998,13(6):1480-1485
The objective of this study was to assess the safety and to make a preliminary assessment of the efficacy of 0.5% ferric hyaluronate adhesion prevention gel in reducing adhesions in patients undergoing peritoneal cavity surgery by laparotomy, with a planned 'second-look' laparoscopy. The study was a randomized, open-label, placebo-controlled, parallel-group design in patients desirous of fertility at the Women's and Children's Hospital, Department of Obstetrics and Gynecology, University of Southern California School of Medicine, Los Angeles, California. Female patients aged 24 to 41 years received 300 ml 0.5% ferric hyaluronate adhesion prevention gel or lactated Ringer's solution as an intraperitoneal instillate at the completion of the laparotomy procedure. At second-look laparoscopy 4-12 weeks after the laparotomy, the presence of adhesions was evaluated. Haematology and serum chemistry were determined throughout the study interval. All patients tolerated the procedures well and did not manifest any serious adverse events. At second-look laparoscopy, patients treated with 0.5% ferric hyaluronate adhesion prevention gel had significantly fewer adhesions than control patients. When adhesions did form, they were significantly less extensive and less severe in patients who received 0.5% ferric hyaluronate adhesion prevention gel. In conclusion, 0.5% ferric hyaluronate adhesion prevention gel was safe and highly efficacious in the reduction of the number, severity and extent of adhesions throughout the entire abdomen following peritoneal cavity surgery. 相似文献
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65.
We present a case where a Wiktor intracoronary stent was inserted for 'poor angiographic result' following balloon angioplasty. Despite appropriate positioning and repeated dilation of the stent a suboptimal result was achieved because of plaque herniation through the stent. The case emphasizes that the choice of stent used is important and will become more so as the number of choices available increases. 相似文献
66.
Grens C.M. Cressler J.D. Andrews J.M. Qingqing Liang Joseph A.J. 《Electron Devices, IEEE Transactions on》2007,54(7):1605-1616
This paper presents a comprehensive picture of operating-voltage constraints in SiGe heterojunction bipolar transistors, addressing breakdown-related issues as they relate to technology generation, bias configuration, and operating-current density. New definitions for breakdown voltage, adopted from standard measurements, are presented. Practical design implications and physical origins of breakdown are explored using calibrated 2-D simulations and quasi-3-D compact models. Device-level analysis of ac instabilities and power performance, which is relevant to mixed-signal circuit design, is presented, and implications of the relaxed voltage constraints for common-base operation are explored. 相似文献
67.
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69.
Responds to the comments by J. J. Kramer (see record 1990-58925-001) on the current author's original article (see record 1986-19878-001), in which Matarazzo contends that computerized clinical psychological test interpretations offer considerable potential for improving the work of health service providers. However, cost additions associated with this technology have increased the probabilities that legislative, judicial, and administrative restrictions and sanctions will be imposed. Here, Matarazzo notes that he finds nothing in Kramer's comments that is inconsistent with the opinions that Matarazzo himself offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Dr Joseph A. Cannataci 《AI & Society》1989,3(3):169-183
This paper examines some of the possible legal implications of the production, marketing and use of expert systems. The relevance of a legally useful definition of expert systems, comprising systems designed for use both by laymen and professionals, is related to the distinctions inherent in the legal doctrine underlying provision of goods and provision of services. The liability of the sellers and users of, and contributors to, expert systems are examined in terms of professional malpractice as well as product liability. A recurring theme indicates that legislators may be inclined to restrict possibilities of liability suits in order to avoid disincentives to the creation of expert systems. 相似文献