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971.
J. K. M. Quartey 《World journal of urology》1987,5(1):37-40
Summary Short traumatic strictures of the membranous urethra can be repaired by excision and end-to-end urethroprostatic anastomosis. Long membranous or bulbomembranous strictures with or without associated periurethral fibrosis, abscess or urinary fistulae require substitution urethroplasty. Tubed full-thickness skin grafts have a poor chance of survival in such circumstances. Scrotal flaps are hairy, but the penile/preputial island flap, which is relatively hairless, is ideal for such reconstructions in one stage. Difficult perineal exposure led to the development of the transpubic and the abdominoperineal routes. Modification of the incision for perineal prostatectomy by dividing the posterior part of the urogenital diaphragm in the midline up to the urethra improves the exposure so that almost all such reconstructions can be done by the perineal route. A total of 21 cases are reviewed. Flap survival is 100%, but stenosis or restricture at the anastomotic sites can occur as a result of faulty technique. These can be treated by internal urethrotomy or excision and reanastomosis. 相似文献
972.
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There is evidence suggesting that the diabetic state adversely affects replication of certain cell populations. We document that exposure to high ambient glucose (20 mM) induces delay in various phases of the cell cycle of human endothelial cells in primary culture. Cells in S phase were labeled with bromodeoxyuridine (an analogue of thymidine), and the cell-cycle position of the labeled cohort was analyzed by flow cytometry at successive time points. The movement of cells exposed to high glucose for 7-8 days was retarded both in S and G2 phases so that the increase in bromodeoxyuridine-positive cells over 24 h was 1.6-fold, versus 2.0-fold in control cultures. In experiments in which mitotic arrest with vinblastine was used to investigate the movement of cells out of G1 phase without interference from reentering cells, depletion of the G1 compartment was significantly inhibited in cultures grown in high glucose. The effects of chronic high glucose on cell cycle occurred while total protein synthesis was not diminished. Acute exposure to high glucose had no effect on cell-cycle traversal or cell generation time. Cell-cycle abnormalities observed in this study may relate to the DNA damage we have previously observed in endothelial cells exposed to high glucose and, if occurring in vivo, could be of pathogenetic importance for the vascular lesions and teratogenicity of diabetes. 相似文献
976.
Failure of genetically selected miniature swine to model NIDDM 总被引:2,自引:0,他引:2
Ten young adult miniature swine from a line reported to be genetically selected for glucose intolerance and eight normal controls were obtained from Colorado State University. They were consecutively exposed to 4 mo of a high-fiber, low-fat standard swine diet; 4 mo of a high-sucrose, high-fat, low-fiber diabetogenic diet; and 4 mo of excess diabetogenic diet for obesification. Results of oral glucose tolerance and intravenous insulin tolerance tests conducted at the end of each regimen were compared. Hyperglycemia was not observed in any animals after any manipulation. Insulin sensitivity was also not influenced by diet. We conclude that F7 low-K miniature swine from this colony fail to model human non-insulin-dependent diabetes. 相似文献
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980.
During the time period 1958-1967 190 cases of male breast cancer were reported to the Swedish Cancer Registry. The reported cases were thoroughly re-evaluated from the evidence of the clinical records and histopathologic specimens. The material contained 166 cases of histologically verified invasive breast carcinoma which were analyzed with respect to different clinical and histopathologic parameters. In contrast to the rate in females, the breast cancer incidence rate in males did not increase significantly during the period under review, and the age-specific incidence rate did not show a Clemmesen's hook but increased relatively more rapidly at high ages than for female breast carcinoma. The mean age at diagnosis was 4 to 5 years higher in male breast cancer patients than in females. Larger tumours were more frequent among older patients and there was a 5-year shift between the age-distribution curves for small (less than 2 cm) and larger (2-5 cm) tumours. A similar difference was found between pN0 and pN1 tumours. This difference might reflect the progression rate of male breast cancer. The histopathology pattern and distribution of histologic malignancy grades were similar to those in female breast carcinoma with the exception that lobular carcinoma and medullary carcinoma with lymphoid infiltration were lacking in the male material. 相似文献