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991.
Native disulphide-bond formation during protein folding in the endoplasmic reticulum requires oxidative machinery, the components and mechanism of which are not yet fully understood. Two recent papers have identified a novel protein component that appears to play a key role in this important redox pathway.  相似文献   
992.
993.
994.
The electrophoretic profiles of outer membrane proteins and lipopolysaccharide of sixty-five enterotoxigenic Escherichia coli of different serotypes and virulence-associated factors, toxin and colonization factors were determined. A close relationship between serotype and outer membrane protein and lipopolysaccharide patterns could be observed. No correlation could be found between the electrophoretic profiles and the expression of virulence-associated factors. The observed homogeneity of outer membrane protein and lipopolysaccharide profiles suggested the presence of only a few clones in the samples studied, and supported the use of outer membrane protein and lipopolysaccharide analysis as a useful epidemiological tool in the characterization of enterotoxigenic Escherichia coli isolates.  相似文献   
995.
We repaired three unselected cases of Descemet's membrane detachment. A visually successful outcome was achieved in one case, an anatomically successful outcome in another, and no improvement in the last. We believe that large detachments should be repaired early rather than waiting for possible spontaneous reattachment, and we advocate sulfur hexafluoride fluid-gas exchange as the procedure of choice.  相似文献   
996.
Digital moving images (AVI format), were integrated into a specific computer-assisted learning (CAL) application, providing a highly visual and interactive self-learning tool in an area of the medical curriculum which is difficult to teach by traditional methods. This paper outlines the process used to obtain the digital video using relatively inexpensive equipment and the subsequent delivery over a university network without resorting to major upgrading of the network specifications.  相似文献   
997.
BACKGROUND AND PURPOSE: We undertook to estimate the frequency of various risk factors and the type and severity of stroke in different ethnic groups documented in a large hospital-based stroke registry. Tel Aviv is a metropolis with about 400000 inhabitants and about 600000 daily visitors and workers. The Tel Aviv Medical Center (TAMC) is the only tertiary medical care facility to which all patients with acute stroke are referred. Israel is a country with a heterogeneous population, of which a significant proportion was born abroad. The people differ in their genetic background, as well as in their early environmental conditions, lifelong diet, and other habits. This variety has proved to be a fertile ground for the study of different neurological diseases, including stroke. METHODS: A prospective hospital-based registry using systematic computer coding of data of all consecutive stroke patients admitted to the TAMC has been conducted since May 1988. Different aspects of the amassed data were analyzed statistically. RESULTS: From May 1988 until April 1994, 3600 stroke patients were admitted to the TAMC. The mean age was 73.2 years, and 58.2% were males. Cerebral infarctions were diagnosed in 80.9%, primary intracerebral hemorrhages in 8.0%, and transient ischemic attacks in 11.1%. There were 861 patients (24%) who were admitted with recurrent strokes. Past medical history of hypertension was the major risk factor (occurring in 52.2% of the patients), followed by ischemic heart disease (29.7%), diabetes mellitus (25.2%), smoking (17.0%), atrial fibrillation (14.3%), and hyperlipidemia (8.4%). Ischemic heart disease and atrial fibrillation were more frequent in patients from Europe and America (Ashkenazi group), whereas diabetes mellitus and smoking were more prominent in the other groups. The in-hospital mortality rate was 13.8% and was similar in both ethnic groups. CONCLUSIONS: This registry allows the study of the risk factors, natural history, and clinical manifestations of stroke in different ethnic groups.  相似文献   
998.
AD Roses  AM Saunders 《Canadian Metallurgical Quarterly》1996,335(26):1996; author reply 1997-1996; author reply 1998
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999.
1000.
Our understanding of the etiologies of the Alzheimer diseases is advancing rapidly, led by the discovery of relevant genetic mutations for autosomal-dominant forms of the disease and widespread confirmation of the role played by apolipoprotein E, the major susceptibility gene for the common form of Alzheimer's disease. New hypotheses are being generated and old hypotheses are being modified to account for the wealth of new information.  相似文献   
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