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31.
Pouchitis: Risk Factors, Etiology, and Treatment 总被引:4,自引:0,他引:4
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33.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
34.
DNA polymerase beta mutations in human colorectal cancer. 总被引:15,自引:0,他引:15
Increasing numbers of alterations have been found in protooncogenes (e.g., ras, myc), as well as tumor suppressor genes (e.g., p53, Rb) in various types of tumors. The multiple mutations cannot be explained by the spontaneous mutation rate. It has been suggested that mutator phenotypes leading to the accumulation of these mutations may be required in the early stages of tumorigenesis. To test this hypothesis, the entire coding region of DNA polymerase beta, a repair enzyme, mRNA from colorectal tumors, and corresponding normal mucosa were amplified by polymerase chain reaction, cloned, and sequenced. Mutations in the catalytic domain of DNA polymerase beta were detected in colorectal tumor specimens compared to the normal colorectal mucosa, placenta, and blood samples. Since these mutations changed the structure of polymerase beta, it is expected that the efficiency of the DNA repair system would be impaired and thus may account for the high mutation rate observed in colorectal carcinomas. 相似文献
35.
Benign osteoblastoma of the occipital bone 总被引:1,自引:0,他引:1
An uncommon case of benign osteoblastoma of the occipital bone is presented. Poor vascularity of the tumor, as confirmed by the CT scan, operative and histopathological findings, was in contrast to its characteristic high vascularity. Radical resection produced an excellent result. 相似文献
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Anjan Banerjee M.Sc. M.S. D.M. Philip Quirke B.M. Ph.D. 《Diseases of the colon and rectum》1998,41(4):490-505
PURPOSE: A review ofin vivo andin vitro models of colorectal cancer is presented. METHODS: A retrospective literature review was performed with reference to CD-ROM Medline and Index Medicus. RESULTS: A comparison of the advantages and disadvantages of the models is presented in addition to a summary of individual model methodology and applications. CONCLUSIONS: Such models are a useful adjunct for surgical research in colorectal oncology.Mr. Banerjee is in receipt of support from the Yorkshire Cancer Research Organization. 相似文献
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The value of fine-needle aspiration biopsy in the cytodiagnosis of salivary gland lesions 总被引:1,自引:0,他引:1
Fine-needle aspiration cytology (FNAC) was performed on 195 cases of salivary gland lesions. The smears were technically adequate in 178 cases. Tissue examination was available for subsequent histocytologic correlation in 57 cases. The cytodiagnosis included inflammatory lesions (59) and benign (68) and malignant (51) tumors (total, 119). The accuracy of cytodiagnosis was 87.7% with a sensitivity of 80.9% and a specificity of 94.3%. Exact histologic typing was possible in 61.9% of the malignant tumors. Mucoepidermoid tumors and cellular-atypical pleomorphic adenoma posed difficulties in cytodiagnosis. 相似文献