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241.
We report an unusual case of a 55 year old Japanese woman with a seminoma but relatively normal menses. The patient was a phenotypic female with late onset menarche (18 years of age), who was amenorrhoeic for the first year, followed by menses of one to three days' slight flow with dysmenorrhoea, but an otherwise normal menstrual history. A typical seminoma was removed from the left adnexal region and an immature testis was identified separately as an associated right adnexal mass. Repeated karyotypic studies on peripheral blood lymphocyte cultures showed only 46,X,-Y,t(Y;15)(q12;p13). Cytogenetic examination of the patient's younger brother, who had fathered three healthy children, showed an identical karyotype. Mosaicism of 46,X,-Y,t(Y;15)(q12;p13)/45,X cell lines was found in skin samples from the patient's elbow and genital regions, although there were no clinical stigmata of Turner syndrome. An androgen receptor binding assay of cultured genital skin fibroblasts was negative. Molecular analysis using Southern blot hybridisation, PCR, and direct DNA sequencing showed that neither the patient nor her brother had a detectable deletion or other abnormalities of Y chromosome sequences, including the SRY (sex determining region of the Y chromosome) gene sequence. These findings suggest that Turner mosaicism of the 45,X cell line may have contributed to this atypical presentation in an XY female, although we cannot exclude abnormalities of other genes related to sex differentiation. 相似文献
242.
In mammals, testosterone and 5alpha-dihydrotestosterone (DHT) are the principal male hormones (androgens). Testosterone is the most abundant circulating androgen, and is converted in specific tissues to DHT by the 5alpha-reductase enzymes. Although each of these androgens binds to the same receptor protein (androgen receptor, AR), each exerts biologically distinct effects. Theories to explain the specific effects of testosterone and DHT have centered on kinetic differences of binding of androgens to the receptor or differences in the metabolic fates of the two hormones. In the current experiments, differential display PCR (ddPCR) was used to identify genes regulated differently by testosterone and DHT. Adult male rats were treated as follows: castrated, treated with Finasteride (an inhibitor of 5alpha-reductase) or left intact for ten days. RNA was prepared from the dissected prostates of these animals and used for ddPCR. Genes exhibiting four distinct patterns of regulation were observed among the mRNAs. Class 1 genes showed equivalent expression in intact and Finasteride-treated animals, but were absent in castrated animals (mRNAs D1, D2, D6, D10). Class 2 genes showed higher expression in intact animals, intermediate levels following Finasteride treatment, but were absent in castrated animals (mRNA D8). Two classes of gene were particularly intriguing: class 3 showed gene expression only in the intact animal (mRNA D7, D9) and class 4 showed increased gene expression following Finasteride treatment (mRNA D3). While the patterns observed for some of these genes (e.g. D8) suggest that the different biological effects of testosterone and DHT may be due to the lower affinity of the AR for testosterone and limiting tissue concentrations of androgen, our results also suggest that some genes expressed in the rat prostate may be regulated in fundamentally different ways in response to testosterone and DHT. 相似文献
243.
G Chow IG Roberts P Fallon M Onoe A Lloyd-Thomas MJ Elliott AD Edwards FJ Kirkham 《Canadian Metallurgical Quarterly》1997,11(4):633-639
BACKGROUND: The precise mechanisms involved in islet xenograft rejection remain unknown. The purpose of the present study was to determine cellular mechanisms responsible for islet xenograft rejection in the liver to facilitate finding a procedure for prevention of immune rejection. METHODS: Hepatic mononuclear cells (MNC) as well as splenocytes, peripheral blood MNC, and thymocytes from streptozotocin-induced diabetic mice (BALB/c) rejecting the intrahepatic rat (Lewis) islet xenografts were isolated and examined by two-color FACS analysis. RESULTS: The characteristic finding of the hepatic MNC from the mice rejecting islet xenografts compared with mice receiving isografts was a significant increase in the yield as well as in the percentage of the cells expressing CD3+ interleukin-2 receptor (IL-2R) alpha- beta+, CD3+ CD8alpha+ beta+, and T cell receptor (TCR) alphabeta+ lymphocyte function-associated antigen-1+. The expression of CD3 and TCR alphabeta of these T cells was found to be of intermediate intensity (TCR(int) cells). The expansion of these TCR(int) cells occurred predominantly in the liver. There was no significant difference in the cells expressing CD3+ IL-2R alpha+, CD3+ CD4+, CD3+ TCRgammadelta+, CD3- IL-2Rbeta+ (natural killer cells), and B220+ (B cells). In vivo administration of anti-IL-2Rbeta monoclonal antibody directed to the expanded cells produced a prevention of rejection. CONCLUSIONS: These findings suggest that islet xenograft rejection in the liver from rat to mouse is an event for which the TCR(int) cells are responsible. 相似文献
244.
245.
Many fundamental and hot band absorption lines of 28Si35Cl+, 28Si37Cl+, 29Si35Cl+, and 30Si35Cl+ have been detectedbetween 630 and 700 cm-1 in a SiCl4/He discharge using diode laser velocity modulation spectroscopy. The datahave been fitted to give seven mass independent coefficients Ukl. The derived spectroscopic constants for 28Si35Cl+ include omegae = 678.24316(18) cm-1 and Be = 0.2870288(14) cm-1. The equilibrium internuclear distance is re =1.9439105(46) ?. The equilibrium dissociation energy calculated from Dunham's expanded Morse potential is De =49 431(57) cm-1. Copyright 1998 Academic Press. 相似文献
246.
247.
CG Tankersley C O'Donnell MJ Daood JF Watchko W Mitzner A Schwartz P Smith 《Canadian Metallurgical Quarterly》1998,85(6):2261-2269
A profile of respiratory complications has been associated with the onset and development of obesity in humans. Similar phenotypes have been routinely demonstrated in genetic animal models of obesity such as the ob mouse (C57BL/6J-Lepob). The objective of the present study was to test the hypothesis that a constellation of respiratory complications are attenuated with leptin (i.e., protein product of the ob gene) replacement. Daily leptin administration during a 6-wk period was conducted to control body weight of mutant ob mice similar to genotypic control groups. During the treatment period, repeated baseline ventilatory measurements were assessed by using whole body plethysmography while quasistatic pressure-volume curves were performed to further explore the role of leptin in improving lung mechanics. Diaphragmatic myosin heavy chain (MHC) isoform phenotype was examined to determine proportional changes in MHC composition. In room air, breathing frequency and minute ventilation were significantly (P < 0.01) different among ob treatment groups, suggesting that leptin opposed the development of a rapid breathing pattern observed in vehicle-treated ob mice. Quasistatic deflation curves indicated that the lung volume of leptin-treated ob mice was significantly (P < 0.05) greater relative to vehicle-treated ob mice at airway pressures between 0 and 30 cmH2O. Diaphragm MHC composition of leptin-treated ob mice was restored significantly (P < 0.05) to resemble the control phenotype. In this genetic mouse model of obesity, the results suggested that respiratory complications associated with the obese phenotype, including rapid breathing pattern at baseline, diminished lung compliance, and abnormal respiratory muscle adaptations, are attenuated with prolonged leptin treatment. 相似文献
248.
JJ Gao MB Filla MJ Fultz SN Vogel SW Russell WJ Murphy 《Canadian Metallurgical Quarterly》1998,161(9):4803-4810
249.
The authors present a patient with complete laryngotracheoesophageal cleft and concurrent left lung agenesis and microgastria. Prenatal ultrasound scan showed polyhydramnios and a hypertrophic right lung. The authors propose that the combination of right lung hypertrophy, polyhydramnios, and microgastria in the absence of a competent laryngeal mechanism may suggest that the preferential path for swallowed amniotic fluid was into the lung, rather than the normal route through the stomach. This case illustrates the prenatal findings suggestive of complete laryngotracheoesophageal cleft and lung agenesis, and suggests a potential causal relationship between shunting of swallowed amniotic fluid into the bronchial tree and prenatal lung hypertrophy and microgastria. 相似文献
250.