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51.
This prospective, randomized study included 18 polycystic ovarian syndrome (PCOS) patients with severe ovarian dysfunction, who were evaluated by standard clomiphene and FSH stimulation. In this group of patients, a 6 month down-regulation with gonadotrophin-releasing hormone (GnRH) analogues gave outcomes similar to laparoscopic ovarian laser diathermy with respect to stimulatory outcome and pregnancy rate. Clomiphene stimulation with 50 mg of clomiphene/day and FSH stimulation in a low-dose, step-up protocol with purified FSH did not result in oligofollicular development; thus patients were divided into two subgroups: one subgroup received laparoscopic laser drilling and the other received 6 months of therapy with GnRH analogues plus add-back therapy after diagnostic laparoscopy. Subsequently, three cycles of low-dose, step-up stimulation with recombinant FSH were started. In both groups, approximately 30% of cycles still remained anovulatory. In the down-regulated subgroup, this mainly happened in the first cycle. In each group, ovulation was achieved in 14 cycles, intrauterine insemination was performed, and five pregnancies were obtained. This resulted in a pregnancy rate of 36% per ovulatory cycle in both groups. Overall, 50% of the formerly unreactive patients in both groups overcame childlessness. In achieving this, long-term treatment with GnRH analogues was as successful as laparoscopic laser diathermy.  相似文献   
52.
Abstract

To better define the sphingolipid metabolism during focal brain ischemia, levels of ceramide, sphingomyelin, cerebroside and gangliosides were determined in rat cerebral cortex during focal ischemia produced by occlusion of the middle cerebral artery. Sphingomyelin began to decrease at 2 hours of ischemia and continued to decrease for 96 hours. In contrast, ceramide increased at 6 hours and increased to 4.2-fold at 96 hours after ischemia, and the fatty acid composition of ceramide was solely nonhydroxylated fatty acid similar to sphingomyelin. Hydroxylated fatty acid-linked cerebroside decreased at 6 hours of ischemia, whereas any significant decrease of nonhydroxylated fatty acid-linked cerebroside didn't occur for 96 hours of ischemia. There were no measurable changes in the levels of gangliosides. These results suggested that ceramide was produced in the cerebral cortex by the breakdown of sphingomyelin during early ischemia. [Neurol Res 1996; 18: 337-341]  相似文献   
53.
放射性核素标记生长抑素类似物在淋巴瘤中的应用   总被引:1,自引:0,他引:1  
生长抑素类似物如奥曲肽、depreotide等与生长抑素受体作用时间长、亲和力高,并可被放射性核素标记,用于肿瘤的生长抑素受体显像和治疗。淋巴瘤细胞表达该受体,因此可利用生长抑素受体对其进行显像和治疗。大量临床和实验研究均表明,放射性核素标记生长抑素类似物的生长抑素受体显像可对淋巴瘤进行诊断、分期、治疗和预后的评价,也可作为常规影像学显像、67Ga和PET显像诊断、评价淋巴瘤的一种有力补充。而在淋巴瘤治疗中的应用应当慎重,如何能获得最佳治疗效果而又将其副作用减小到最低程度是今后研究的主要课题之一。  相似文献   
54.
BackgroundAlthough physical properties of neonatal-infantile stratum corneum (SC) change drastically after birth, precise developmental alterations of specific sites have not been fully elucidated.ObjectiveTo determine the longitudinal alterations of neonatal-infantile SC functions and components of upper thighs and diaper-covered buttocks during the first year of life. The data were compared with those of adults.MethodsNineteen full-term neonates and their mothers were subjected to the measurements. Skin hydration, water sorption/retention capacity, TEWL were measured. Superficial SC analyses for NMF, ester binding sebum, and free fatty acids were performed by ATR-FTIR spectrometer. Total amount of ceramides (CERs) and CER subclasses were analyzed by NPLC-ESI-MS.ResultsSC hydration of neonatal thighs was lower than that of their mothers, which rapidly increased during the 1st month. Skin hydration of neonatal buttocks was similar to that of their mothers. This also rapidly increased during the 1st month. The neonatal TEWL was less than those of their mothers indicating more efficient barrier function at both sites, which significantly increased during the 1st year development. This was mostly correlated decreased in the ω-hydroxy fatty acid-esterified CERs. Superficial ester-binding sebum content of neonates was similar to that of their mothers, which significantly decreased during the measurement; the decrease was more marked on buttocks. Neither NMF nor FFA of the superficial SC showed significant alteration during the 1-year development.ConclusionOur results indicate that physical functions and components of neonatal-infantile SC show considerable alterations between diaper-covered buttocks and upper thighs during the 1st year development.  相似文献   
55.
神经酰胺对人膀胱癌细胞凋亡诱导作用及其机制   总被引:2,自引:0,他引:2  
孔垂泽  时京  王侠  李振华  朱育焱  曾宇 《中华实验外科杂志》2006,23(10):1159-1161,i0001
目的 探讨神经酰胺(cer)对人膀胱癌细胞的凋亡诱导作用及其机制。方法 不同浓度C2-神经酰胺(C2-cer)作用于膀胱癌T24细胞,噻唑蓝(MTT)比色法检测细胞存活率,吖啶橙(AO)荧光染色、流式细胞术(FCM)检测细胞凋亡,并对半胱天冬酶(Caspase)-3活性、bcl-2蛋白含量和细胞色素C在细胞内的分布变化进行检测。结果 T24细胞存活率与C2-cer浓度呈负相关(r=-0.973,P<0.01)。对照组和5、10、20、40μmol/L的C2-cer处理组凋亡率分别为2.95%、9.18%、14.23%、29.12%、48.46%,C2-cer处理组凋亡率显著高于对照组(P<0.01)。Caspase-3活性随C2-cer浓度增加而增加,与对照组比较差异有统计学意义(P<0.05)。在C2-cer作用下,T24细胞内bcl-2蛋白含量下降,细胞色素C向细胞质释放。结论 降低bcl-2蛋白表达水平,从而促进线粒体细胞色素C释放和Caspase-3激活可能是C2-cer诱导膀胱癌细胞凋亡的重要机制。  相似文献   
56.
时京  孔垂泽  孙志熙  王侠  罗阳  刘奔  张莹  刘博 《中华实验外科杂志》2006,23(10):1162-1164,i0001
目的 观察丝裂霉素C(MMC)与C2-神经酰胺(C2-cer)联合应用对人膀胱癌细胞的作用效果,并探讨其机制。方法 不同浓度MMC与C2-cer单独及联合作用于人膀胱癌BIU-87细胞后,应用噻唑蓝(MTT)比色法检测细胞生长抑制率,计算合用指数(CI),流式细胞仪(FCM)检测BIU-87细胞凋亡率,吖啶橙(AO)荧光染色观察凋亡形态学变化,Western blot检测细胞色素C在细胞内分布变化,并检测Caspase-3活性改变。结果 单独应用时MMC与C2-cer的中效浓度分别是159和28μmol/L,联合用药时下降为55和11μmol/L,CI=0.74。MMC与C2-cer单独及联合应用均可导致BIU-87细胞出现凋亡的形态学变化。两种药物联合应用时的凋亡率高于各自单用(P<0.05)。线粒体细胞色素C含量在MMC与C2-cer单独及联合应用时均较对照组减少,联合用药时减少最为明显,细胞质内细胞色素C含量在联合用药时增加也最为明显(P<0.05)。Caspase-3活性在MMC与C2-cer单独及联合应用时均较对照组升高,联合用药时升高最为明显(P<0.05)。结论 MMC与C2-cer联合应用可以通过共同诱导细胞凋亡,协同抑制膀胱癌细胞生长。线粒体细胞色素C释放和Caspase-3活性变化可能发挥重要作用。  相似文献   
57.
Ceramide synthases (CerS) synthesise ceramides of defined acyl chain lengths, which are thought to mediate cellular processes in a chain length-dependent manner. In experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), we observed a significant elevation of CerS2 and its products, C24-ceramides, in CD11b+ cells (monocytes and neutrophils) isolated from blood. This result correlates with the clinical finding that CerS2 mRNA expression and C24-ceramide levels were significantly increased by 2.2- and 1.5-fold, respectively, in white blood cells of MS patients. The increased CerS2 mRNA/C24-ceramide expression in neutrophils/monocytes seems to mediate pro-inflammatory effects, since a specific genetic deletion of CerS2 in blood cells or a total genetic deletion of CerS2 significantly delayed the onset of clinical symptoms, due to a reduced infiltration of immune cells, in particular neutrophils, into the central nervous system. CXCR2 chemokine receptors, expressed on neutrophils, promote the migration of neutrophils into the central nervous system, which is a prerequisite for the recruitment of further immune cells and the inflammatory process that leads to the development of MS. Interestingly, neutrophils isolated from CerS2 null EAE mice, as opposed to WT EAE mice, were characterised by significantly lower CXCR2 receptor mRNA expression resulting in their reduced migratory capacity towards CXCL2. Most importantly, G-CSF-induced CXCR2 expression was significantly reduced in CerS2 null neutrophils and their migratory capacity was significantly impaired. In conclusion, our data strongly indicate that G-CSF-induced CXCR2 expression is regulated in a CerS2-dependent manner and that CerS2 thereby promotes the migration of neutrophils, thus, contributing to inflammation and the development of EAE and MS.  相似文献   
58.
The anthelmintic activity of 11 benzimidazole derivatives (A1-A11) and 2 thioureides N,N′-disubstituted (B1-B2) was determined. Each compound and albendazole was tested in vitro against Toxocara canis larvae and in vivo against Hymenolepis nana adult. Compounds A1-A6 and B1-B2 were designed as albendazole prodrugs. Compounds A8-A11 were designed as direct analogues of A7, which had previously proved to be an effective agent against Fasciola hepatica. Results of the in vitro screening showed that A6 was more active than albendazole at 0.18 μM (relative mobility 40% and 80%, respectively). Whereas that the in vivo evaluation against H. nana, compounds A7-A11 demonstrated significant activity in terms of removing cestode adults in the range of 88-97%, displaying better efficacy than albendazole (83%).  相似文献   
59.
p53R2, a recently discovered small subunit of human ribonucleotide reductase, is believed to play essential roles in DNA repair, mtDNA synthesis, and protection against oxidative stress. Because of the positive correlation between the level of this protein and drug sensitivity and tumor invasiveness, it constitutes a potential target for anticancer drugs as well as a diagnostic marker in cancer.  相似文献   
60.
1,4-Dihydropyridines have been recognized as calcium channel agonist. Three new analogues of Bay K8644 in which the ortho trifluromethyl phenyl group at position 4 is replaced by the 4-(5)-Chloro-2-ethyl-5-(4)-imidazolyl substituent, were designed and synthesized as calcium channel agonist. For this propose, the structures of designed compounds were drawn by HYPERCHEM program. Conformations of the compounds were optimized through semi-empirical method followed by PM3 calculation. Then the crystalin stucture of L-type calcium channel was obtained from the Protein Data Bank (PDB) server. Docking calculations were carried out using Auto-Dock.4 program. The good interaction of our 1,4-DHP derivatives showed that they can be as possible calcium channel agonist agents. Finally compounds were synthesized according to a modified Hantzsch condensation procedure.  相似文献   
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