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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
5.
Péter Móricz Imre Gerlinger Jenő Solt Krisztina Somogyvári József Pytel 《European archives of oto-rhino-laryngology》2007,264(12):1441-1445
Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy
and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic
balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases.
In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The
average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature
data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every
effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major
myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap
needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free
flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in
prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and
neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter
dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure
provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However,
a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion
of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications. 相似文献
6.
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
7.
Effect of change of fecal bile acid excretion achieved by operative procedures on 1,2-dimethylhydrazine-induced colon cancer in rats 总被引:5,自引:0,他引:5
Dr. Krisztina Morvay M.D. Károly Szentléleki M.D. Géza Török M.D. Alan Pintér M.D. Mátyás Börzsönyi M.D. Reinhard Nawroth DSc 《Diseases of the colon and rectum》1989,32(10):860-863
The effect of bile on the development of 1,2-dimethylhydrazine (DMH)-induced colon cancer was studied in male Wistar rats. Experimental operative models were created, in which in Group 1, the half intestinal tract, the ileum, and the right side of colon were released from bile. In Group 2, both sides of the colon contained bile. The sham operated animals formed Group 3. These techniques changed the concentration of bile acid in different parts of the colon, and the daily total fecal bile acid excretion as well. After DMH treatment, the relationship between these changes of bile acid level and the development of colon cancer was studied. Significantly more tumors than in the control group were found if the daily total bile acid level and the bile acid concentration in the left side of the colon were increased. Our findings show an unambiguous connection between the fecal bile acid level and the incidence of DMH-induced colon cancer. 相似文献
8.
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
9.
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
10.
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