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Hyperoxaluria is frequently seen in patients with inflammatory bowel disease, or after resection of the ileum. It is assumed to be responsible for the development of nephrolithiasis, nephrocalcinosis (oxalate nephrosis) and progressive renal impairment in these patients. Steatorrhea may aggravate the severity of hyperoxaluria. A 60-year-old male underwent massive resection of the jejunum and ileum 10 years prior to admission, due to strangulation of the small bowel, with occlusion of the superior mesenteric artery. He remained well except for steatorrhea which developed two-and-a-half years prior to admission, when microhematuria, proteinuria and oxaluria developed progressively. Since that time, the nephrolithiasis, nephrocalcinosis and renal failure have continued to worsen despite therapy with oxalate restriction and oxalate-binding agents. A renal biopsy, performed late in the clinical course, showed severe changes in the renal parenchyma. The decline in renal function proved irreversible. The unusual metabolic consequences of massive resection of the small intestine and their mechanisms are discussed.  相似文献   
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Follistatin and activin A production by the male reproductive tract   总被引:1,自引:0,他引:1  
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   
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Maternal serum concentrations of inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids and gonadotrophins were measured longitudinally in six normal singleton pregnancies. Maternal venous blood was collected randomly during a spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11, 16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the early puerperium. Steroid and gonadotrophin profiles conformed to previous reports. While at week 5 of gestation inhibin-A, activin-A and follistatin concentrations were similar to those at the follicular phase, all three increased progressively (P < 0.001) to maximal concentrations in week 36: approximately 48-fold (3740 +/- 1349 ng inhibin-A/ml), approximately 22-fold (6109 +/- 1443 ng activin-A/ml) and approximately 10-fold (3563 +/- 418 ng follistatin/ml) higher. Pro- alphaC concentrations reached a maximum in weeks 5 (approximately 5- fold, P < 0.001) and 36 (1027 +/- 174 pg/ml, P < 0.01). Inhibin-B (71 +/- 23 pg/ml prior to pregnancy) was undetectable (<12 pg/ml) between week 5-16 of gestation but increased slightly in the third trimester (26 +/- 7 pg/ml in week 36). Activin-AB was undetectable throughout pregnancy. Post-partum concentrations of inhibin-A (41 +/- 12 ng/ml), inhibin-B (<12 pg/ml), activin-A (950 +/- 149 pg/ml), pro-alphaC (128 +/- 22 pg/ml) and follistatin (990 +/- 79 ng/ml) were substantially lower than at week 36 of gestation. The activin-A:follistatin ratio increased from 0.5 in week 5 to 1.8 in week 36, suggesting that more free activin-A is available in the maternal circulation during late pregnancy.   相似文献   
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Fuh JL  Wang SJ  Lu SR  Juang KD  Chiu LM 《Maturitas》2001,39(2):117-124
OBJECTIVES: This paper aims to report the methodology of a study of a cohort of middle-aged women in Taiwan, their age at menopause, and related factors and prevalence of menopausal symptoms, and to examine the relationships between symptoms and sociodemographic variables. METHODS: An epidemiological study of neuropsychological change during the menopausal transition among Chinese women aged 40-54 years old on the islet of Kinmen. RESULTS: Of a targeted population of 2256 individuals, 1497 (66%) participated in the study. The mean age at menarche was 15.6 years and that at menopause was 48 years. The hormone use rate at the time of study was 23% in surgical menopausal women, and 9% were past users. After excluding surgical menopausal and premenopausal women, 6% reported a current use of estrogen replacement therapy and 6% were past users. The most frequently reported discomforts for those women aged >45 were troubled sleep, backaches, and joint pain. Four symptom clusters: musculoskeletal, non-specific somatic complaints, urogenital, and vasomotor, were identified. After adjustment for age, the urogenital and vasomotor symptoms were significantly associated with menopausal status. CONCLUSIONS: The age at menopause did not differ much from Western studies, but the menopausal symptoms, especially the vasomotor symptoms, were much lower in our study population. Nevertheless, vasomotor symptoms were still significantly associated with menopausal status.  相似文献   
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Breast cancer detection: one versus two views   总被引:2,自引:0,他引:2  
Mammographic examinations of 169 patients with 172 biopsy-proved carcinomas, and of 194 healthy subjects, were interpreted independently and retrospectively by three experienced mammographers, initially as single-view oblique examinations and 6 months later as two-view oblique-cephalocaudal examinations. For the single-view examinations of the cancer patients, 67% of the cancers were correctly recommended for biopsy, additional views were requested for 23%, and a "negative" interpretation was made for 10%. For the single-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were recommended for 32%. For the two-view examinations of women with cancer, 80% of the cancers were correctly recommended for biopsy, additional views were requested for 4%, and a "negative" interpretation was made for 16%. For two-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were requested for only 5%. The authors conclude that single-view screening should not be performed, because it would lead to an excessive number of "call-back" examinations of healthy patients, producing additional cost and anxiety that would outweigh any theoretical benefit.  相似文献   
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