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81.
Lodewyckx L Vandevyver C Vandervorst C Van Steenbergen W Raus J Michiels L 《Human mutation》2001,18(3):243-250
A method for mutation detection in the alpha-1 antitrypsin gene (protease inhibitor 1; PI) has been developed using denaturing gradient gel electrophoresis of PCR amplified gene fragments. Using this experimental approach, all common phenotypes and mutations could be detected. Denaturing gradient gel electrophoresis (DGGE) was compared with standard isoelectric focusing (IEF) in 20 potential alpha1-antitrypsin deficient patients and their relatives. The genotype determined by DGGE was found to be more reliable in some cases than IEF, which is essential for a proper diagnosis of alpha-1 antitrypsin malfunctioning. 相似文献
82.
ObjectiveTo
understand the mechanism of liver cirrhosis after the infection of hepatitis B virus.MethodsMouse
fibroblast NIH3T3 cells were transfected with 3.2 kb HBV DND by exposure of the cells to
calcium phosphate.The change of the levels of mRNA for tissue inhibitor of
metalloproteinase 1and 2(TIMP1,2) was detected in mouse fibroblast NIH3T3 cells and the cells of transfection
with HBV Genome by in situ hybridization.ResultsThe levels of mRNA for
TIMP1 and TIMP2 were increased significantly.ConclusionHBV infection can
induce the expression of the mRNA for TIMP1 and TIMP2. 相似文献
83.
84.
Yang AH Chen JY Chen BF 《Virchows Archiv : an international journal of pathology》2004,445(3):305-314
While diffuse mesangial sclerosis is traditionally described as being the glomerulopathy of Denys–Drash syndrome (DDS), the podocyte proliferative lesions may be overlooked in these DDS cases. In the present study, an evolving process is extrapolated from a selected case of DDS that demonstrated glomerulopathy with conspicuous podocyte proliferation. The observation that podocytes express proliferation markers (Ki67, proliferating-cell nuclear antigen and topoisomerase II) in non-proliferative, mature-looking glomeruli suggests an initial pathogenic act to activate or to keep podocytes from quiescence. The subsequent proliferation of podocytes is in keeping with downregulation of WT1 and cyclin kinase inhibitors of p16 and p21. The emergence of cytokeratin-positive cells in glomeruli that show typical mesangial sclerosis implies elimination of podocytes and replacement with tubular and/or parietal epithelial cells. The final scene of evolving glomerulopathy displays apoptosis and expression of Fas-L and Bax in sclerotic mesangial lesions, which eventually end up with global sclerosis. This novel concept of DDS glomerulopathy implies complex molecular mechanisms involved in glomerular injury. 相似文献
85.
人TFPI基因转染对兔移植静脉血栓形成和近期通畅率的影响 总被引:1,自引:0,他引:1
目的: 为减少冠状动脉旁路移植术后血栓形成,探讨人组织因子途径抑制因子(TFPI)基因转染对兔移植静脉血栓生成的影响。方法:构建真核表达质粒pCMV-(Kozak)TFPI。采用阳离子脂质体和腔内加压灌注法,转染移植静脉内皮细胞。RT-PCR、Western blotting和免疫组化法检测外源基因在兔移植静脉中的表达。病理标本、扫描电镜观察移植静脉血栓形成情况,血管多普勒观测其通畅率。结果:移植静脉中有人TFPI基因和蛋白表达。静脉移植术后3 d,基因转染组、空载体和空白对照组分别有1条、8条和7条移植静脉发生血栓,术后30 d,以上各组分别有0条、5条和5条移植静脉完全闭塞,前者静脉血栓发生率和闭塞率均低于后两者(P<0.05)。扫描电镜显示两对照组内皮表面有红细胞和血小板黏附、聚集,而转染组基本正常。结论:人TFPI基因干预,减少了兔移植静脉血栓形成,提高了近期通畅率。 相似文献
86.
Inge Van de Walle Karen Silence Kevin Budding Liesbeth Van de Ven Kim Dijkxhoorn Elisabeth de Zeeuw Cafer Yildiz Sofie Gabriels Jean-Michel Percier Johanna Wildemann Jan Meeldijk Peter J. Simons Louis Boon Linda Cox Rob Holgate Rolf Urbanus Henny G. Otten Jeanette H.W. Leusen Peter Boross 《The Journal of allergy and clinical immunology》2021,147(4):1420-1429.e7
87.
S. Suzuki T. Iwabuchi T. Tanaka S. Kanayama M. Ottomo M. Hatanaka H. Aihara 《Acta neurochirurgica》1985,77(3-4):133-141
Summary The prevention of cerebral vasospasm with OKY-046, an imidazole derivative and a thromboxane synthetase inhibitor, was studied co-operatively at ten neurosurgical services. Intravenous administrations of 2, 5 or 10 /kg/minute of OKY-046 were given continuously from the earliest possible day to the 14th SAH-day to 82 pateints with ruptured cerebral aneurysm. Sixty-eight patients (83%) showed moderate to high high-density (SAH) in their initial CTs. Angiographic vasospasms were seen in 58 patients, representing 71% of all cases or 81% of the 72 cases for which angiograms were available; the vasospasms of 45 patients (55 or 63%) were moderate to severe. Symptomatic vasospasm occurred, however, only in 27 patients (33%); in 18 of those cases, moreover, the symptoms were mild or transient. The conditions of the patients at one month after the SAH were classified into 9 grades from 0 (normal) to 8 (deceased). Fifty-two patients (63%) were classified as 0 or 1, and 64 (78%) as better than 3 (possible daily life unaided). The administration of OKY-046 was proven to decrease TXB2 in the blood.This paper emphasizes the effectiveness of the drug for symptomatic vasospasm, and supports our previous contention that cerebral microthrombosis may play an important role in the pathogenesis of cerebral vasospasm. 相似文献
88.
R. Ortmann M. Schaub A. Felner J. Lauber P. Christen P. C. Waldmeier 《Psychopharmacology》1984,84(1):22-27
Stereotyped sniffing behavior together with forepaw padding — defined as the -phenylethylamine (PEA) syndrome — is induced by MAO-B inhibitors in rats injected with 30 mg/kg IP PEA. The comparison of the abilities of the MAO-B inhibitors to induce the syndrome and to inhibit MAO-B in rat brain homogenates indicated that at least 75% of MAO-B activity in rat brain had to be inhibited to induce the PEA syndrome. A good correlation was found between the abilities of MAO-B inhibitors to induce the behavioral syndrome and to increase levels of PEA in rat brain. Specific MAO-A inhibitors potentiated the behavioral effect of the MAO-B inhibitor deprenyl, while they did not induce the syndrome themselves or only at very high doses. Inhibitors of the reuptake of 5-HT or noradrenaline were inactive under the described experimental conditions. This behavioral test system seems to be useful in vivo screening test in rats for detecting compounds with strong MAO-B inhibiting activity. 相似文献
89.
目的:探讨钠氢交换抑制剂二甲基氨氯吡咪(DMA)对低浓度油酸(OA)所致的血管内皮损伤的保护作用。方法:分别用OA及OA+DMA温育离体大鼠胸主动脉环,观察其对乙酰胆碱(Ach),硝普钠(SNP),L-N-硝基精氨酸甲酯(L-NAME)的反应。结果:OA(10-4mol·L-1)温育30min后,Ach诱导的舒张反应减弱,最大舒张从64%降低到28%;L-NAME诱导的收缩反应也减弱,最大收缩由52%降低到34%。而对SNP诱导的舒张反应无影响。如用DMA(10-6mol·L-1)+OA温育30min,则可部分恢复单用OA引起的Ach的舒张反应及L-NAME收缩反应的减弱,Ach的最大舒张恢复到47%,L-NAME的最大收缩恢复到45%。 结论:DMA对OA所致的血管内皮损伤具有保护作用。 相似文献
90.
12例垂体瘤做原代细胞培养 ,检测了表皮生长因子 ( EGF)及染料木黄酮 ( Genistein)对肿瘤细胞 3H- Td R掺入率及酪氨酸激酶产物表达的影响。研究表明 EGF使大部分功能性腺瘤及所有非功能性腺瘤细胞的 3H- Td R掺入率明显增加 ,酪氨酸激酶活性增强 ,而 Genistein能抑制 EGF的作用使所有瘤细胞的 3H- Td R掺入率下降。提示表皮生长因子对垂体瘤细胞有明显的增殖刺激作用 ;Genistein能消除表皮生长因子的细胞增殖刺激作用 ,抑制肿瘤细胞增生 ,对垂体瘤治疗有重大意义。 相似文献