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21.
本文报告65例双炔失碳酯配伍d1-15甲基PGF_(2α)(以下简称PG)抗早孕结果并与33例丙睾配伍PG抗早孕结果进行比较。结果显示,双炔失碳酯组完全流产59例,占90%;不全流产3例,占5%;失败3例,占5%;总有效率95%。丙睾组完全流产27例,占82%;不全流产6例,占18%;总有效率100%。两组总有效率无显著差异;完全流产率无显著差异;但不全流产率有明显差异(P<0.05)。药流后点滴出血天数,双炔失碳酯组平均为8.1±5.0天;丙睾组平均为18.9±19.1天;两组有明显差别(P<0.05)。双炔失碳酯经阴道给药后无一例发生心、肝、肾功能变化。 相似文献
22.
目的探讨缺氧诱导因子-1α(HIF-1α)在ESWL致肾脏损伤中的作用及黄芪是否通过调节HIF-1α的表达而发挥对肾脏的保护作用。方法45只家兔随机分为对照组、ESWL损伤组和黄芪治疗组,每组15只,除对照组外,所有动物接受ESWL处理(18kV,1 500次)。黄芪治疗组家兔于冲击前3d至后2d,每天注射黄芪注射液2.0g/kg。2周后处死家兔,取肾脏HE染色观察肾组织形态学改变,免疫组织化学染色观察HIF-1α在肾脏中的表达。结果ESWL处理后肾小管上皮细胞肿胀、脱落,小管内可见大量管型,肾间质大量炎细胞浸润;黄芪治疗组以上病变显著减轻。ESWL损伤组HIF-1α显著表达于肾小管上皮细胞及间质,黄芪能够明显抑制HIF-1α的表达。结论HIF-1α参与了ESWL对肾脏的损伤,黄芪可能通过抑制HIF-1α的表达发挥对肾脏的保护作用。 相似文献
23.
P. MORSING A. STENBERG D. CASELLAS A. MIMRAN C. MÜLLER-SUUR C. THORUP L. HOLM A. E. G. PERSSON 《Acta physiologica (Oxford, England)》1992,146(3):393-398
Atrial natriuretic peptide (ANP), injected at physiological concentrations, is known to induce both natriuresis and diuresis. It has been suggested by some investigators that these changes result from an increasing glomerular filtration rate (GFR), but others have been unable to demonstrate an increased GFR. The tubuloglomerular feedback (TGF) mechanism is an important regulator of GFR, and the sensitivity of TGF is decreased during ANP administration. Furthermore, resetting of TGF is, in most instances, related to changes in renal interstitial hydrostatic and oncotic pressures. It is also known that ANP may increase capillary permeability which may change renal interstitial pressure. The present study was performed to examine renal interstitial pressures and the TGF mechanism during ANP infusion. In accordance with previous studies, TGF sensitivity was found to be decreased. The tubular flow rate which elicited half the maximal drop in stop-flow pressure (Psf) was increased from 18.5 to 25.7 nl min-1. In contrast, ANP infusion resulted in a decreased interstitial hydrostatic pressure and an increased interstitial oncotic pressure. From previous experiments, such changes in interstitial pressures would be expected to increase TGF sensitivity. The changes in interstitial pressure cannot, therefore, directly explain the resetting of the feedback mechanism. In conclusion, the present paper shows a decreased renal net interstial pressure after intravenous administration of ANP. 相似文献
24.
25.
Immunoglobulin mimicry by Hepatitis C Virus envelope protein E2 总被引:4,自引:0,他引:4
Hu YW Rocheleau L Larke B Chui L Lee B Ma M Liu S Omlin T Pelchat M Brown EG 《Virology》2005,332(2):538-549
Hepatitis C virus (HCV) establishes persistent infection in the majority of infected individuals. The currently accepted hypothesis of immune evasion by antigenic variation in hypervariable region 1 (HVR1) of glycoprotein E2 does not however, explain the lack of subsequent immune recognition. Here, we show that the N-terminal region of E2 is antigenically and structurally similar to human immunoglobulin (Ig) variable domains. E2 is recognized by anti-human IgG antibodies and also possesses common amino acid (aa) sequence features of the conserved v-gene framework regions of human Ig light chains in particular but also heavy chains and T cell receptors. Using a position specific scoring system, the degree of similarity of HVR1 to Ig types correlated with immune escape and persistence in humans and experimentally infected chimpanzees. We propose a unique role for threshold levels of Ig molecular mimicry in HCV biology that not only advances our concept of viral immune escape and persistent infection but also provides insight into host-dependent disease patterns. 相似文献
26.
We previously reported the expression profiles of 9 cytochrome P450 isozymes (CYPs) proteins and those of 40 CYPs genes in pregnant rat's liver, placenta and fetal liver after treatment with pregnenolone-16alpha-carbonitrile (PCN) or phenobarbital (PB). This study was carried out focusing on the gene expression profiles of Phase II drug metabolizing enzymes, Glutathione S-transferase isozymes (GSTs) and UDP-glycosyltransferase isozymes (UDPGTs). Fischer 344 (F344) pregnant rats were daily treated intraperitoneally with 50 mg/kg of PCN or 80 mg/kg of PB from 13 to 16 days of gestation (DG). They were sacrificed on 17 DG, and microarray analysis using Affymetrix Rat Expression Array 230 A was performed. Among 16 GSTs genes examined in this study, 7 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 8 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. On the other hand, among 11 UDPGTs genes examined, 5 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 5 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. There were no significant changes in the placenta of all groups. This is the first report of the gene expression profiles of Phase II drug metabolizing enzymes in pregnant rat and fetal livers and placenta after treatment with typical inducers of drug metabolizing enzymes. 相似文献
27.
《Immunity》2020,52(6):1075-1087.e8
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28.
为观察转染α黑素细胞刺激素(-αMSH)基因的树突状细胞(DC)的功能和特性,以腺相关病毒(AAV)为载体将α-MSH基因导入小鼠骨髓来源的未成熟DC(-αMSH-DC),用ELISA检测-αMSH-DC培养上清中-αMSH及IL-12水平,用流式细胞仪分析-αMSH-DC表面分子的表达,以-αMSH-DC提呈OVA抗原刺激致敏T细胞,通过ELISA测定IL-2水平来观察其抗原提呈功能。结果显示,在-αMSH-DC培养上清中检测到-αMSH的分泌,-αMSH-DC表面分子表达下调,分泌IL-12的能力降低,抗原提呈功能被抑制。-αMSH-DC可部分抵抗LPS上调表面分子表达和促进IL-12分泌的作用。表明-αMSH基因可籍AAV载体导入未成熟DC,并有效地表达,α-MSH基因修饰的DC成熟受到抑制。 相似文献
29.
Prime SS Eveson JW Stone AM Huntley SP Davies M Paterson IC Robinson CM 《The Journal of pathology》2004,203(4):927-932
This study examined the behaviour of nine human malignant oral keratinocyte cell lines following orthotopic transplantation to the floor of the mouth of athymic mice. Tumourigenesis, local spread, and metastatic dissemination were correlated with known cellular responses to transforming growth factor-beta 1 (TGF-beta 1). Six of nine cell lines were tumourigenic; four of these cell lines showed local spread which was characterized by vascular and bone invasion. Metastatic spread was uncommon, with only 9% of animals with primary tumours developing metastases and these were almost exclusively found in the regional lymph nodes; there was one pulmonary metastasis and no liver deposits. Tumour cell behaviour did not reflect the clinical stage of the original tumours. Cell lines that were resistant to TGF-beta 1-induced growth inhibition were more likely to form primary tumours, exhibit local spread, and metastasize than cells that were growth-inhibited by the ligand. The data demonstrate that tumourigenicity and tumour behaviour in this orthotopic mouse model varied between cell lines and that the pattern of local invasion and metastasis was similar to that seen in human oral cancer. Furthermore, cell lines that were refractory to the growth inhibitory effects of TGF-beta 1 behaved more aggressively than cells that underwent ligand-induced cell-cycle arrest. 相似文献
30.
Comparative study of pituitary and bacteria-derived human growth hormone by monoclonal antibodies 总被引:1,自引:0,他引:1
We have established hybridoma lines which secrete mouse monoclonal antibodies (Mabs) to human pituitary growth hormone, hGH. Using indirect competitive ELISA and indirect passive hemagglutination inhibition twelve different Mabs were characterized with regard to cross-reactivity with the hGH-related hormones, human chorionic somatomammotropin, hCS, and human prolactin, hPRL. The reactivity of these Mabs with pituitary hGH was compared to that with either bacterially-produced methionyl-hGH or to that of reduced and S-carboxymethylated hGH, which has an altered conformation. None of the Mabs reacted with hPRL. Four did not react with hCS whereas the others showed varying degree of cross-reactivity with hCS. All Mabs reacted more weakly with reduced and S-carboxymethylated hGH than with the native form of the hormone, which was not seen with conventional rabbit antisera to hGH. Thus in the case of hGH the Mabs are superior to conventional antisera in revealing small conformational differences. However the pituitary and bacterially-derived methionyl-hGH were indistinguishable as determined by the 12 Mabs. 相似文献