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991.
Current methods of predicting prognosis in transitional cell carcinoma of the bladder fail to provide consistently reliable information about future tumour behaviour. The monoclonal antibody Ki67 recognises an antigen present in actively dividing cells and Ki67 reactivity has been shown to correlate with conventional prognostic indicators in several tumours. In this study, Ki67 antibody was used to determine the proportions of cells undergoing active division in 26 transitional cell carcinomas of the bladder. The proportion of cells stained in muscle invasive tumours (12.3 +/- 5.4%) was significantly greater than in superficial tumours (4.3 +/- 1.9%) and poorly differentiated tumours showed significantly greater proportions of cells staining compared with well or moderately well differentiated tumours. These results show that Ki67 reactivity correlates with high tumour stage and poor differentiation. Ki67 staining provides an easy method of determining tumour cell turnover that might provide additional prognostic information. 相似文献
992.
993.
994.
The authors examined the possibility that ethane 1,2-dimethanesulphonate (EDS) has a cytotoxic effect on spermatogenesis that is not secondary to androgen withdrawal resulting from the well known cytotoxic effect of EDS on Leydig cells. Adult male rats were implanted with polydimethylsiloxane (PDS) capsules containing testosterone (T) and estradiol (E), and were simultaneously injected with EDS. The PDS-TE implants, by inhibiting luteinizing hormone (LH) production, prevented Leydig cells from repopulating the testis and clamped testosterone within the seminiferous tubules at increasing concentrations relative to implant size. In rats that received EDS alone, the number of advanced spermatids per testis was significantly reduced by 2 weeks, but within 8 weeks returned to the numbers maintained in vehicle-injected control rats or in vehicle-injected rats that received testosterone- and estradiol-filled capsules of 24 cm and 0.1 cm, respectively (PDS-24TE). Surprisingly, in rats that received an EDS injection plus PDS-24TE implants, the number of advanced spermatids per testis was significantly reduced at 8 weeks and severe seminiferous tubule atrophy occurred despite the fact that the testosterone concentration was sufficient to quantitatively maintain spermatogenesis in vehicle-injected rats. In rats injected with EDS and implanted with 24 cm testosterone but not estradiol-filled capsules (PDS-24T), the advanced spermatid number per testis was significantly higher than that in the EDS plus PDS-24TE rats, but significantly lower than that in control rats. These results suggest that EDS may have a cytotoxic effect on the seminiferous epithelium that is independent of the elimination of Leydig cells, and the EDS and estradiol act synergistically to exert a profound toxic effect on spermatogenesis. 相似文献
995.
R. M. Fairchild C. E. J. Daniels P. R. Ellis† 《Journal of human nutrition and dietetics》1990,3(5):311-316
A food frequency of consumption questionnaire was completed by 137 diabetic outpatients attending the University of Wales Hospital in Cardiff, to provide information about the use of special dietary products.
Seventy-four per cent of the diabetics used special dietary products, the most popular of which were artificial sweeteners (45%) and preserves (47%), followed by squash (34%), sweets (31%) and chocolate (31%). Twenty per cent of diabetics consumed biscuits and tinned fruit. Cake and other products (e.g. jelly), were used by less than 10% of the respondents. Over half of all the diabetics consumed one or more products on a daily basis. The use of special products bore no significant relationship to the sex of the respondents, nor to the duration of the diabetes. However, a significantly higher proportion of the Insulin Dependent Diabetics (IDDM) group used dietary products compared with the Non-Insulin Dependent Diabetics (NIDDM) group. This can be explained largely by the differences in age between the diabetics; the under-18-year-old age group (who were all IDDM respondents) were the greatest users of sweets, chocolate and squash.
Forty-three per cent of diabetics who did not use special food products cited at least one reason for non-use. The reasons included dietetic advice (NIDDM respondents only), high cost, poor palatability, lack of availability and unsuitability for other members of the family. 相似文献
Seventy-four per cent of the diabetics used special dietary products, the most popular of which were artificial sweeteners (45%) and preserves (47%), followed by squash (34%), sweets (31%) and chocolate (31%). Twenty per cent of diabetics consumed biscuits and tinned fruit. Cake and other products (e.g. jelly), were used by less than 10% of the respondents. Over half of all the diabetics consumed one or more products on a daily basis. The use of special products bore no significant relationship to the sex of the respondents, nor to the duration of the diabetes. However, a significantly higher proportion of the Insulin Dependent Diabetics (IDDM) group used dietary products compared with the Non-Insulin Dependent Diabetics (NIDDM) group. This can be explained largely by the differences in age between the diabetics; the under-18-year-old age group (who were all IDDM respondents) were the greatest users of sweets, chocolate and squash.
Forty-three per cent of diabetics who did not use special food products cited at least one reason for non-use. The reasons included dietetic advice (NIDDM respondents only), high cost, poor palatability, lack of availability and unsuitability for other members of the family. 相似文献
996.
997.
S E Campbell C D Phillips E Dubovsky W S Cail R A Omary 《AJNR. American journal of neuroradiology》1995,16(7):1385
PURPOSETo determine whether plain films alone are sufficient in the evaluation of stability of simple wedge-compression fractures of the lumbar spine.METHODSPlain films and CT scans of 53 consecutive patients seen during a 2-year period with lumbar spine fractures were retrospectively reviewed. Six readers blinded to the CT diagnosis independently read each patient''s plain films. Plain-film findings were scored on a five-point graded response scale using criteria proposed by Gehweiler and Daffner. In addition, a fracture was considered to be possibly unstable if there was involvement of more than one vertebral level or greater than 50% loss of anterior vertebral body height. CT findings represented the standard for comparison. CT scans were independently evaluated by three additional readers. Two-column involvement, middle-column involvement alone but with retropulsion, multiple-level involvement, or greater than 50% loss of vertebral height indicated potential instability.RESULTSFor 14 stable and 39 potentially unstable lumbar spine fractures, the pooled (mean) plain-film negative predictive value for detection of potentially unstable fractures was 0.62 (95% confidence interval, 0.53 to 0.70), with a sensitivity of 0.83 (95%, confidence interval; 0.78 to 0.87), and specificity of 0.80 (95% confidence interval, 0.70 to 0.87).CONCLUSIONPlain films are not adequate for determining stability of lumbar spine fractures. 相似文献
998.
999.
L Graves D J Stechschulte D C Morris B P Lukert 《Journal of bone and mineral research》1990,5(11):1113-1119
A 59-year-old male presented with systemic mastocytosis with extensive skeletal involvement resulting in vertebral compression fractures and bone pain. Histomorphometric analysis of bone revealed increased mast cells, elevated static parameters of bone resorption, and low bone formation. Serum calcium, phosphorus, and alkaline phosphatase were normal; however, serum 1,25-dihydroxyvitamin D3 and osteocalcin levels were low. Histamine levels in plasma and urine were elevated. Following therapy with ketotifen, the patient had resolution of bone pain along with decreased flushing and pruritus. Elevated plasma and urine histamine levels normalized, as did 1,25-dihydroxyvitamin D3 and osteocalcin levels. Indices of low bone formation improved on therapy. Eroded surfaces improved but remained elevated. This case is the first demonstration that bone symptoms and histomorphometric change in systemic mastocytosis are reversed with inhibition of mast cell degranulation. The role of mast cells and their products in bone metabolism is poorly understood, but the therapy of bone disease in systemic mastocytosis should include inhibition of the release of mast cell products along with the use of histamine antagonist. 相似文献
1000.