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1.
Characteristics of hyperparathyroid states in the Canadian multicentre osteoporosis study (CaMos) and relationship to skeletal markers 下载免费PDF全文
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Ectopic prolactin secretion from a gonadoblastoma 总被引:1,自引:0,他引:1
A 6.5-year-old girl developed isosexual, pseudoprecocious puberty secondary to a gonadoblastoma. The tumor was found to produce and secrete both immunoassayable and bioassayable prolactin based on immunohistochemical techniques and the presence of a prolactin gradient between the tumor vein and peripheral vein. The source of the prolactin was a Sertoli-like cell. Neither growth hormone nor growth hormone-releasing hormone was detected within the tumor. This case confirms the ectopic production of prolactin by neoplastic tissue. 相似文献
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Analysis of epidermal growth factor receptor and activated epidermal growth factor receptor expression in pituitary adenomas and carcinomas. 总被引:2,自引:0,他引:2
Onder Onguru Bernd W Scheithauer Kalman Kovacs Sergio Vidal Long Jin Shuya Zhang Katharina H Ruebel Ricardo V Lloyd 《Modern pathology》2004,17(7):772-780
Epidermal growth factor receptor plays an important role in the pathogenesis of many malignancies. Various growth factors, including epidermal growth factor receptor, have been shown to influence pituitary tumor growth and differentiation. To analyze the role of epidermal growth factor receptor in pituitary tumor development, we examined normal pituitaries (n=8), pituitary adenomas (n=158), and pituitary carcinomas (n=7) for expression of epidermal growth factor receptor protein and messenger RNA using tissue microarrays and RT-PCR. We also examined (a) the expression of phospho-epidermal growth factor receptor, the activated form of epidermal growth factor receptor, in pituitary tumors and normal pituitaries by immunohistochemistry and (b) the effects on epidermal growth factor receptor expression of treating pituitary cells (HP75 cell line) with epidermal growth factor. Epidermal growth factor receptor and the phosphorylated variant expression were present in normal pituitary cells. Epidermal growth factor receptor messenger RNA was also detected in normal pituitaries, pituitary adenomas, and carcinomas by in situ hybridization and RT-PCR. Most pituitary adenomas showed expression of epidermal growth factor receptor and the phosphorylated variant. Nonfunctional adenomas showed higher levels of expression of epidermal growth factor receptor (76 vs 34%) and of phospho-epidermal growth factor receptor (26 vs 8%) as compared to functional adenomas. Five of seven pituitary carcinomas showed strong expression of both epidermal growth factor receptor and phospho-epidermal growth factor receptor. When a human pituitary cell line (HP75) was cultured in the presence of epidermal growth factor receptor, there was an increase in the levels of both epidermal growth factor receptor and phospho-epidermal growth factor receptor after 5 h of treatment, thus confirming that epidermal growth factor receptor signaling was active in pituitary tumors. These results indicate that activated epidermal growth factor receptor is expressed in pituitary adenomas and carcinomas. Higher levels in pituitary carcinomas suggest a role in pituitary tumor progression. 相似文献
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K Kovacs E Horvath 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1988,43(15):405-407
This review summarizes some aspects of pituitary adenoma pathology. A new embracing pituitary adenoma classification has been developed which correlates morphologic findings with endocrine activity. It is based on hormone content, histologic, immunohistochemical and ultrastructural features, cellular composition and cytogenesis, and separates pituitary adenomas into 7 distinct entities. 相似文献
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István Pintér János Mátyus Zoltán Czégány Judit Harsányi Marietta Homoki Miklós Kassai Eva Kiss István Kiss Erzsébet Ladányi Lajos Locsey Lajos Major Mihály Misz Lajos Nagy Kálmán Polner Jeno Rédl István Solt Béla Tichy Marietta T?r?k Gábor Varga Gyula Wagner Imre Wórum Béla Zsoldos László Pótó Katalin Dérczy István Wittmann Judit Nagy 《Nephrology, dialysis, transplantation》2004,19(4):840-843
BACKGROUND: The diagnosis of analgesic nephropathy has improved significantly with modern imaging techniques. We reviewed a large portion of the Hungarian dialysis population to obtain additional insight into the problem. METHODS: Twenty-two participating dialysis units enrolled 1400 patients on renal replacement therapy between 1 January 1995 and 1 January 1998. Patients with no known aetiology (n = 284) were interviewed and studied with renal imaging. We assessed the presence of decreased renal mass combined with either bumpy contours, papillary calcification, or both. The subjects studied were interrogated extensively. RESULTS: Our survey suggested analgesic nephropathy in 47 of 1400 patients (3.3%), 3-fold higher than the EDTA database estimate for Hungary. The analgesics most commonly abused were phenacetin-containing mixtures. The driving symptoms were mainly headache and joint pain. Cardiovascular complications were more common than in the rest of the dialysis population, independent of smoking and lipid values (P<0.01). CONCLUSIONS: Phenacetin should be banned. Our study results support the need for longitudinal cohort and case-control studies in Hungary. 相似文献
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S J Sherman B W Kovacs A L Medearis M B Bear R H Paul 《The Journal of reproductive medicine》1992,37(9):804-808
Twin pregnancies have higher perinatal morbidity and mortality rates than singleton pregnancies. Researchers have demonstrated that one major benefit of prenatal care in the twin gestation is reduced fetal death rate. This study to determine the relationship of nonstress tests (NSTs) to pregnancy outcome in twin gestations comprised 665 women who delivered at Los Angeles County-University of Southern California Women's Hospital from January 1985 to January 1989. These patients, all of whom had prenatal care (PNC), were subdivided into two groups: (1) PNC and NSTs and (2) PNC and no NSTs. The groups did not differ statistically with regard to gravidity, parity and abortions. NSTs were selectively done on twin gestations complicated by discordancy or other fetal/maternal complications. Ten pregnancies were complicated by fetal demise of one or both twins in patients who received prenatal care without NSTs. Among the NST group there was one fetal demise. Although the NST group had fewer fetal deaths, the reduction was not statistically significant (P = .062). Infant birth weight was identified as a confounder because the NST group had a statistically higher mean birth weight. Definitive proof of the ability of NSTs to reduce the fetal death rate in twin gestations complicated by discordancy or other pregnancy complications awaits a large, prospective, randomized trial. 相似文献
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Preoperative hemostatic activity and excessive bleeding after cardiopulmonary bypass 总被引:2,自引:0,他引:2
The rationale for predicting the risk of excessive postoperative bleeding by assessing the hemostatic status of a patient before cardiopulmonary bypass was investigated. A novel, rapid, overall test (hemostatometry) consisting of a physiologically relevant test of platelet function (shear-induced hemostasis) and coagulation was performed using nonanticoagulated blood and compared with the routine coagulation screen. Two hundred five patients undergoing elective coronary revascularization were studied 3 to 4 days before operation. Forty-nine bled excessively for nonsurgical reasons; none were predicted by the routine coagulation tests. Using a stepwise discriminant analysis, hemostatometry correctly predicted 31 of 49 (63%). Thirty of 156 predicted as bleeders by hemostatometry did not bleed. Thus, preoperative hemostatometry predicted 77% of the true outcome. The false predictions suggest, however, that certain bleeding abnormalities probably acquired during cardiopulmonary bypass cannot be predicted. These findings do not justify the routine use of preoperative tests in assessing the bleeding risk in patients undergoing cardiopulmonary bypass. 相似文献
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