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991.
BACKGROUND: Predictors of fertility or spermatogenesis during gonadotrophin therapy of gonadotrophin-deficient men remain poorly defined. METHODS AND RESULTS: In order to evaluate potential predictors, this study evaluated 29 consecutive gonadotrophin-deficient men all desiring paternity who received 43 courses of therapy in one centre between 1982 and 1998. The Kaplan-Meier survival analysis estimates of median (SE) time to a sperm concentration of >0, >5 and >20 x 10(6)/ml were 5.5 (1.1), 12.4 (2.3) and 29.1 (1.9) months respectively. Conception occurred in 22/43 cycles (with eight men achieving two pregnancies) with a median (SE) Kaplan-Meier estimate of 20.5 (4.7) months. The median sperm concentration at conception was 5.0 (SE 2.0; range 0.0-59.5) x 10(6)/ml. Multivariate correlated Cox proportional hazards models predicting these same sperm thresholds and conception were developed by forward stepwise variable selection with verification of the model by backward stepping. Larger testicular volume, prior gonadotrophin therapy, completion of puberty, older age, the absence of adverse fertility factors and the absence of multiple pituitary hormone deficiency predicted a favourable response. Multivariate modelling suggests that the two most important predictors of sperm output are testicular volume and pubertal status. The most important potentially modifiable predictor was prior gonadotrophin therapy. The efficacy of recombinant and urinary FSH were similar. Prior androgen therapy and partner's age did not appear to be significant. CONCLUSIONS: Since prolonged treatment may be required to induce spermatogenesis, attention to these predictors may allow appropriate early use of advanced reproductive technologies.  相似文献   
992.
The hypothalamus regulates many aspects of energy homeostasis, adjusting both the drive to eat and the expenditure of energy in response to a wide range of nutritional and other signals. It is becoming clear that various neural circuits operate to different degrees and probably serve specific functions under particular conditions of altered feeding behaviour. This review will discuss this functional diversity by illustrating hypothalamic neurones that express neuropeptide Y (NPY), the melanocortin-4 receptor (MC4-R) and the orexins. NPY neurones in the arcuate nucleus (ARC) release NPY, a powerful inducer of feeding and obesity, in the paraventricular nucleus (PVN) and the lateral hypothalamic area (LHA). ARC-NPY neurones are inhibited by leptin and insulin and become overactive when levels of these hormones fall during undernutrition. They may function physiologically to protect against starvation. With disruption of the inhibitory leptin signals due to gene mutations, the NPY neurones are overactive, which contributes to hyperphagia and obesity in the ob/ob and db/db mice and fa/fa Zucker rat. The MC4-R is activated by alpha-melanocyte-stimulating hormone [alpha-MSH; a cleavage product of pro-opiomelanocortin (POMC), which is expressed in the other ARC neurones] and inhibits feeding. This effect is antagonised by agouti gene-related peptide (AGRP), which is coexpressed by the ARC-NPY neurones only. Activation of MC4-R, possibly mediated by blockade of AGRP release, appears to restrain overeating of a palatable diet. This response may be programmed by a transient rise in leptin soon after presentation of palatable food, and rats that fail to do this will overeat and become obese. Orexin-A and -B (corresponding to hypocretins 1 and 2) are expressed in specific LHA neurones. These have extensive reciprocal connections with many areas involved in appetite control, including the nucleus of the solitary tracts (NTS), which relays vagal afferent satiety signals from the viscera. Orexin neurones also have close anatomical connections with LHA glucose-sensitive neurones. Orexin-A induces acute feeding but does not cause obesity. Orexin neurones are stimulated by hypoglycaemia partly via the NTS and inhibited by food ingestion. These neurones may therefore be involved in the severe hyperphagia of hypoglycaemia and short-term control of feeding.  相似文献   
993.
53例脂肪肉瘤形态学观察与预后探讨   总被引:1,自引:1,他引:1  
报道53例脂肪肉瘤(高分化型7例、粘液型34例、圆细胞型3例及多形性型9例)。男性34例,女性19例。高发年龄41~60岁。主要症状是无痛性(51/53)或痛性肿块。肿瘤直径为3~24cm,多数有包膜(37/53)。8例作了超微结构观察,分别对四型脂肪肉瘤的超微结构特征进行了详细描述。随访结果显示圆细胞型预后差,高分化型预后好;肿瘤体积大,核分裂象多者预后差;肿瘤体积小,核分裂象少者预后好。  相似文献   
994.
Due to the sharp increase in liver transplant candidates and the subsequent shortage of suitable donor livers, an extension of the current donor criteria is necessary. Simple cold storage, the current standard in organ preservation has proven to be insufficient to preserve extended criteria donor livers. Therefore a renewed interest grew toward alternative methods for liver preservation, such as hypothermic machine perfusion and normothermic machine perfusion. These “new” preservation methods were primarily assessed in rat models, and only a few clinically relevant large animal models have been described so far. This review will elaborate on these alternative preservation methods. Anat Rec, 291:735–740, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
995.
Hexige S  Guo J  Ma L  Sun Y  Liu X  Ma L  Yan X  Li Z  Yu L 《Neuroscience letters》2005,389(2):83-87
Growth/differentiation factor 3 is a member of GDF/BMP subfamily of the TGF-beta superfamily, which has been reported to be implicated in testis carcinoma and deposition of adipose tissue. Interestingly, present work indicated that GDF3/Gdf3 genes were expressed in cerebral cortex, hippocampus as well as in cerebellum, as revealed by RT-PCR, in situ hybridization and immunostaining. Results of RT-PCR in 10 human tissues and 12 rat tissues indicated that GDF3/Gdf3 genes were abundantly transcribed in both human and murine brain, including cerebral cortex, hippocampus and cerebellum. In situ hybridization and immunohistochemistry results revealed that in cerebral cortex, GDF3 was evenly distributed. In hippocampus, it was expressed in most of the neurons in CA2 and DG region, especially only in a restricted number of neurons in the regions of CA1 and CA3 and in Purkinje cells in cerebellum. Present data suggested that GDF3 might play important roles in the central nervous system (CNS), especially in cerebral cortex, hippocampus and cerebellum, and it shed new light on further research of GDF3 in the central nervous system.  相似文献   
996.
Mitomycin (MMC), like many antineoplastic drugs, induces a predictable, dose-related, bone marrow depression in man and laboratory animals; this change is generally reversible. However, there is evidence that MMC may also cause a late-stage or residual bone marrow injury. The present study in female CD-1 mice investigated the haematological and bone marrow changes induced by MMC in a repeat dose study lasting 50 days. Control and MMC-treated mice were dosed intraperitoneally on eight occasions over 18 days with vehicle, or MMC at 2.5 mg/kg, autopsied (n = 6-12) at 1, 7, 14, 28, 42 and 50 days after the final dose and haematological changes investigated. Femoral nucleated bone marrow cell counts and levels of apoptosis were also evaluated and clonogenic assays carried out; serum levels of FLT3 ligand (FL) were assessed. At day 1 post-dosing, MMC induced significant reductions in RBC, Hb and haematocrit (HCT) values, and there were decreases in reticulocyte, platelet, and femoral nucleated cell counts (FNCC); neutrophil, lymphocyte and monocyte values were also significantly reduced. On days 7 and 14 post-dosing, all haematological parameters showed evidence of a return towards normal values, but at these times, and at day 28, values for RBC and FNCC remained significantly reduced in comparison with controls. At days 42 and 50 post-dosing, many haematological parameters in MMC-treated mice had returned to control levels; however, there remained evidence of late-stage effects on RBC, Hb and HCT values, and FNCC also continued to be significantly decreased. Results for granulocyte-macrophage colony-forming units and erythroid colonies showed a profound decrease immediately post-dosing, but a return to normal values was evident at day 50. Serum FL concentrations demonstrated very significant increases in the immediate post-dosing period, but a return to normal was seen at day 50 post-dosing; a relatively similar pattern was seen in the number of apoptotic femoral marrow nucleated cells. The histopathological examination of kidney tissues from MMC animals at day 42 and 50 post-dosing showed evidence of hydronephrosis with cortical glomerular/tubular atrophy and degeneration. It is therefore concluded that MMC administered on eight occasions over 18 days to female CD-1 mice at 2.5 mg/kg induced profound changes in haematological and bone marrow parameters in the immediate post-dosing period with a return to normal levels at day 50 post-dosing; however, there was evidence of mild but significant late-stage/residual effects on RBC and FNCC, and on cells of the erythroid lineage in the bone marrow.  相似文献   
997.
998.
The purpose of the present study is to investigate the role of manganese superoxide dismutase (MnSOD) gene polymorphisms in the susceptibility to psoriatic arthritis. MnSOD gene polymorphisms were determined by polymerase chain reaction/restriction fragment length polymorphisms method in fifty-two patients with psoriatic arthritis and 90 healthy controls. The genotype frequency of MnSOD 1183C/T was significantly higher in patients with psoriatic arthritis than in controls. In contrast, the frequency of MnSOD 1183T/T was significantly decreased in patients with psoriatic arthritis. The phenotype frequency of MnSOD 1183C was significantly increased in patients with psoriatics arthritis in comparison to healthy controls. Therefore, MnSOD 1183C polymorphisms may be a precipitating factor for the development of psoriatic arthritis.  相似文献   
999.
1000.
分析27例消化道癌症患者(其中胃癌18例,食道癌与结肠癌9例)和6例胃溃疡病人的血浆纤维连接蛋白(Fn)的变化。结果发现三者间无明显差异(P>0.05),但胃癌病人中有转移病灶者(n=7)及伴胃炎者(n=10)与相应对照组比,血浆Fn有非常明显降低(p<0.01)。胃癌组织中Fn免疫荧光主要集中在胃癌病人胃壁组织多形核白细胞浸润的炎症区及微血管周围,癌变区Fn免疫荧光很弱,甚至消失。对上述变化的意义进行了讨论。  相似文献   
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