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991.
992.
It has been shown that the X-ray-sensitive Chinese hamster V79 mutants (V-E5, V-C4 and V-G8) are similar to ataxia-telangiectasia (A-T) cells. To determine whether the AT-like rodent cell mutants are defective in the gene homologous to A-T (group A, C or D), human chromosome 11 was introduced to the V-E5 and V-G8 mutant cells by microcell-mediated chromosome transfer. Forty independent hybrid clones were obtained in which the presence of chromosome 11 was determined by in situ hybridization. The presence of the region of chromosome 11q22-23 was shown by molecular analysis using polymorphic DNA markers specific for the ATA, ATC and ATD loci. Seventeen of the obtained monochromosomal Chinese hamster hybrids contained a cytogenetically normal human chromosome 11, but only twelve hybrid cell lines were shown to contain an intact 11q22-23 region. Despite the complementation of the X-ray sensitivity by a normal chromosome 11 introduced to A-T cells (complementation group D), these twelve Chinese hamster hybrid clones showed lack of complementation of X-ray and streptonigrin hypersensitivity. The observed lack of complementation does not seem to be attributable to hypermethylation of the human chromosome 11 in the rodent cell background, since 5-azacytidine treatment had no effect on the streptonigrin hypersensitivity of the hybrid cell lines. These results indicate that the gene defective in the AT-like rodent cell mutants is not homologous to the ATA, ATC or ATD genes and that the human gene complementing the defect in the AT-like mutants seems not to be located on human chromosome 11.  相似文献   
993.
994.
This study tested whether a 12-week dynamic resistance strength training program can change gait velocity and improve measures of balance among adults age 65 and older. Fifty-five community-dwelling adults (mean age = 71.1) were randomized into an exercise (n = 25) or control (n = 30) group. The exercisers were requested to complete three bouts of strength training per week for 12 weeks using elastic tubing. At posttest the exercisers demonstrated slower gait velocity, enhanced balance, and an improved ability to walk backward, although none of these posttest measures was significantly different from the control group.  相似文献   
995.
996.
997.
We have assessed, by intravital microscopy in rats, the effects of different anaesthetics on diaphragmatic arteriolar diameter. Rats were anaesthetized with etomidate, propofol or thiopental (groups E, P and T, respectively) and the diameters of the arterioles were measured sequentially at baseline and after topical application of either mefenamic acid (MA, 20 mumol litre-1) or N omega-nitro-L-arginine (NNA, 300 mumol litre-1), inhibitors of prostaglandins and nitric oxide, respectively. In group E, baseline arteriolar diameters were significantly higher than those in the two other groups (P < 0.01). MA and NNA induced significant constriction in the three groups (P < 0.001). However, whereas constriction induced by NNA was similar in the three groups, constriction induced by MA was significantly higher in group E compared with groups P and T (P < 0.05). We conclude that diaphragmatic arteriolar diameters in rats were greater during etomidate than during thiopental or propofol anaesthesia. This phenomenon may be mediated by prostaglandins.  相似文献   
998.
Skin symptoms on the hands were studied in questionnaire-based studies conducted in 1989 and 1991 among female cleaners employed at Danish nursing homes, schools and offices. Eleven hundred and sixty-six participated in 1989 and 1011 of them participated in 1991. The average age was 45 years and the average length of five employed as a cleaner was ten years. Forty-three percent reported to have had at least one out of four skin symptoms during a one year period. Seventy percent reported improvement during week-ends and holidays. A positive correlation was found between hours per week spent with wet hands and skin symptoms. During the follow-up period the risk of developing skin symptoms was higher in the group who remained cleaners compared with the group who left the cleaning job. Similarly, the prognosis was better in the group which left the cleaning job compared with the group which remained cleaners. There is a future need to develop and implement new work organisation and cleaning methods to reduce the time spent with wet hands.  相似文献   
999.
A major focus of leprosy research in the last 10 years has been the identification and characterization of antigens of Mycobacterium leprae that interact with antibodies and T cells of the host's immune response. Through the combined efforts of many different laboratories, a substantial number of protein antigens have been identified and characterized. In this MicroReview we present an updated list of M. leprae protein antigens, and, with emphasis on recent developments, summarize what is known regarding their functional and immunological features.  相似文献   
1000.
Open reduction and internal fixation has become the standard of care for the treatment of most displaced acetabular fractures. As surgical techniques have become refined, long term results of surgical fixation have improved. During the past 10 to 15 years, several controversies have surfaced in the orthopaedic literature regarding the treatment of acetabular fractures. The recent literature regarding acetabular fixation was reviewed. Controversies include the most efficacious surgical approach for complex acetabular fractures; the effectiveness of intraoperative sciatic nerve monitoring; the most effective method of prophylaxis against deep vein thrombosis; and the indications for and method of prophylaxis against heterotopic bone formation.  相似文献   
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