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251.
252.
Cervical biopsy samples were taken from 79 patients who had various grades of cervical intraepithelial neoplasia or who showed evidence, in the form of koilocytosis, of human papillomavirus infection of the uterine cervix and from 10 women with normal cervices. The DNA content of the cells in the samples was analysed by flow cytometry. Analysis of the data obtained showed that the biopsy samples from women with cervical intraepithelial neoplasia and human papillomavirus lesions contained significantly more dividing cells (31.2% of cells from human papillomavirus lesions with no cervical intraepithelial neoplasia and 33.06%, 29.89%, and 31.76% of cells from cervical intraepithelial neoplasia grades I, II, and III, respectively) than those from women with normal cervices (21.6%). The proportion of aneuploid samples from the group who showed evidence of human papillomavirus infection only (18.2%) did not differ significantly from the group with cervical intraepithelial neoplasia grade III (21.2%). Aneuploidy and an increased rate of cellular proliferation are recognised characteristics of malignancy. These results therefore support the view that human papillomavirus plays an important part in the aetiology of cervical carcinoma and are relevant to the clinical management of patients.  相似文献   
253.
The claim that list sizes in general practice should continue to fall towards a national average of 1700 patients rests heavily on the assumption that the extra time available to doctors would be used mainly for longer consultations, resulting in better standards of care. Evidence suggests, however, that the time is more likely to be used to increase rates of consultation in surgeries and home visits and to reduce the length of the working week. A national, random sample of 2104 principals in general practice in England and Wales were questioned about their allocation and use of time. The response rate was 67%, and no large biases in response were detected. The smaller their personal list size the less time general practitioners spent on all aspects of their work and the higher their rates of consultation and home visiting. The effects of further reductions in list sizes would be haphazard, being differentially distributed across the range of list sizes. Longer consultations would probably result, but most of the extra time would probably be used in higher rates of consultation in surgeries and home visits and some would be taken as free time.  相似文献   
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The catalytic behavior and structural features of Ca2+-ATPase in the vesicles of longitudinal tubules and terminal cisternae of the sarcoplasmic reticulum isolated from rabbit skeletal muscles was analysed. pH measurements have shown under optimal conditions Ca2+-ATPase has similar catalytic behavior both in the fractions of longitudinal tubules and terminal cisternae. Under non-optimal conditions, the behavior similarity was not observed. The specific activity of the ATPase enzyme under optimal conditions was shown to be much higher in the fraction of longitudinal tubules than in the fraction of terminal cisternae. Caffeine added to both fractions had no effect on the catalytic behavior of Ca2+-ATPase. As judged from fluorescence analysis, the structure of Ca2+-ATPase of longitudinal tubules differs from that structure of terminal cisternae. In sarcoplasmic reticulum membrane, at least half of the tryptophan residues of Ca2+-ATPase was shown to be buried in the lipid bilayer. Our findings suggest that in terminal cisternae some of the Ca2+-ATPase molecules exist as an oligomeric protein and do not participate in ATP hydrolysis (named "silent" Ca2+-ATPase).  相似文献   
256.
'Classical nitroreductase' is an enzyme involved in the intracellular metabolic activation of mutagenic nitroarenes. The nitroreductase gene of Salmonella typhimurium TA1538 was cloned into pBR322 and the plasmids harboring the gene were introduced into TA98 and TA100. The resulting strains (YG1021 and YG1026) had more than 50 times higher nitrofurazone-reductase activity than TA1538 containing pBR322, and were extremely sensitive to the mutagenic action of 2-nitrofluorene, 1-nitropyrene and 2-nitronaphthalene. These results indicate that the new strains permit the efficient detection of mutagenic nitroarenes.  相似文献   
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258.
Westphalian A-C coal-bearing strata and red-beds in the Pennine Basin of Central and Northern England contain a wide variety of palaeosols. In coal-bearing facies associations alluvial, gley, semi-gley, organic and rare well-drained palaeosols reflect the predominance of poor drainage conditions during deposition. In red-beds more evolved ferruginous and ferallitic palaeosols testify to free drainage conditions during deposition. Catenary relationships can be inferred between most of the palaeosols in both facies associations, providing further information on the palaeogeomorphology of the depositional systems, and assisting in the understanding of the environments and conditions of coal seam formation.  相似文献   
259.
The soft-tissue chin may become ptotic following surgery in this area. The mentalis muscles which are responsible for proper central lip motion and chin point position may be affected. The mentalis muscle origin may require resuspension at a proper level. This reattachment may be performed by means of an intraoral approach. Non-absorbable sutures are used to hold the soft-tissue chin upward. The exact method involves placing drill holes through the alveolar bone, into which sutures are passed. These sutures are then placed through the lower mentalis muscles and tightened. Chin and lip position may be corrected in certain cases. Ancillary procedures are required to correct vestibular scarring and submental scars.  相似文献   
260.
The results of multidrug therapy of 44 male patients with non-seminomatous testicular tumours are discussed. The diagnosed tumours were of all stages of the clinical advances and were treated with combined chemotherapy (surgery and PVP regimen). Thirty two patients (73%) are followed up between 7 and 103 months and survived, complete remission is noted in 29 patients (66%) including 6 patients who survived over 5 years. Symptoms of the tumour are found in 3 patients. Twelve patients (27%) died. The treatment did not produce life-threatening complications. The obtained results have been compared with those reported by other authors.  相似文献   
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