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991.
Objective To investigate variations in hepatitis B virus (HBV) polymerase gene in chronic HBV infected patients resistant to lamivudine therapy. Methods Specimens were obtained from nine patients with chronic HBV infection, who were resistant to lamivudine therapy. Partial segments of the HBV DNA polymerase gene we re amplified by polymerase chain reaction (PCR). Nucleotide sequence was performed using an applied 373 automated sequencer. Titre of HBV DNA was measured by branched DNA assay (Chiron). Results Of nine patients with HBV DNA positive after 64 weeks of treatment, five (56%) had variations in the highly conserved YMDD motif in domain C of the HBV polymerase, three of those were substitutions of isoleucine for methionine(M), and two were substitutions of valine(V) for methionine. Additionally, in two patients with variations characterized by substitutions of V for M, one had a simultaneous amino acid change from the first aspartic acid to glycine and this pattern of variation was not reported in other literatures. With respect to viremia, in two subjects with low titre of HBV DNA (<100 MEq/ml), no variation was found in the YMDD motif, whereas in seven patients with high titre of HBV DBA (>300 MEq/ml), five (71%) had variations in the YMDD motif. Conclusions Lamivudine is a potent anti-viral agent for treatment of chronic HBV infection. Resistance to lamivudine is likely caused by the variations in the YMDD motif of the HBV polymerase gene. 相似文献
992.
Objective To evaluate apoptosis in lupus nephritis and the relationship between the existe nce of apoptotic cells in renal tissue and histopathological or clinical changes .Methods Apoptosis was detected by in situ nick-end labeling techniques (TUNEL) in renal biopsies from 25 patients with type Ⅳ lupus nephritis (LN), 12 patients with I gA nephropathy IgAN, 4 patients with idiopathic mesangioproliferative glomerulon ephritis (MsPGN) and 3 patients with acute poststreptococcal glomerulonephritis (APGN).Normal renal tissue obtained at nephrectomy for hypernephroma in 4 adul ts was used as control.Proliferating cells were identified by proliferating ce ll nuclear antigen (PCNA) in these patients. Results Compared to other proliferative glomerulo-nephritis and controls, the patients w ith lupus nephritis had less apoptotic cells, a higher ratio of PCNA+ cells/TdT+ cells (P/T) in renal tissues; and their P/T ratio in glomeruli and tubuloin terstitium correlated with the chronicity index, r=0.4983 (P=0.0132), r=0.8399 (P<0.001), r=0.6614 (P=0.0033), respectively.P/T ratios in the glomerulus and tubule had a positive correlation with 24-hour uri nary protein, r=0.8554 (P<0.001) and r=0.7134 (P=0.001); and a negative correlation with creatinine clearance (Ccr), r=-0.4880 (P=0 .0133) and r=-0.7229 (P=0.001), which in tubules positively corre lated with serum creatinine (Scr), r=0.4107 (P=0.0414).Conclusions Apoptosis is reduced in proliferative lupus nephritis.Intense proliferation wi thout a commensurate increase in apoptosis is a possible mechanism that leads to chronic progressive renal histopathological changes. 相似文献
993.
上海社区糖尿病前期及糖尿病人群视网膜病变患病率及相关危险因素分析 总被引:1,自引:0,他引:1
Objective To determine the prevalence and risk factors of diabetic retinopathy (DR) in the Diabetes Mellitus (DM) and impaired glucose regulation (IGR) population in Shanghai Community. Methods DR screening after the epidemiologic study of metabolic syndrome in Huayang and Canyang Community , Shanghai was conducted among 1300 patients with DM or IGR during June 2005 and March 2006, Digital non-mydriatic fundus photography was performed for each eye in all subjects. Other factors, including diabetes related history, BMI, WHR, fasting plasma glucose, HbAlc, serum lipid and blood pressure were also assessed. 642 patients,312 males and 330 females, aged 65 ± 13, with complete data were enrolled into the analysis. Results The prevalence of DR was 19. 9% in the diabetic population, and the prevalence of mild, moderate, severe non-proliferative retinopathy and proliferative retinopathy was 12. 0%, 5. 1%, 2. 3% and 0. 5%, respectively; the prevalence of DR in IGR reached 8. 0%. Logistic regression analysis revealed that HbA1c level and diabetes duration were both independently associated with diabetic retinopathy. Conclusion The prevalence of DR was high in both DM and IGR population. Bad blood glucose control and long diabetes duration both increased occurrence of DR. 相似文献
994.
Objective To evaluate the role of endogenous ouabain (EO) in the development of hypertension and the characteristics of EO secretion in 1k1c (one kidney, one clipped) hypertensive rats. Methods EO content of serum and tissues in 1k1c hypertensive rats and normal control Sprague-Dawley (SD) rats was detected by the method of enzyme linked immunosorbent assay (ELISA). The relationship between serum or tissue ouabain and blood pressure was analyzed in 1k1c hypertensive rats. Results The ouabain content of serum, heart, kidney, adrenal gland, pituitary and hypothalamus was significantly higher in 1k1c hypertensive rats than that in normal control SD rats (2.25, 2.63, 3.35, 40.37, 3.34, 15.7 μg/kg tissue in 1k1c hypertensive rats vs 1.12, 1.79, 1.73, 27.54, 1.83, 10.10 μg/kg tissue in control SD rats, respectively. P<0.05 for all of these comparisons). The ouabain content of the adrenal gland and the hypothalamus was higher than that of other tissues or serum, both in 1k1c rats and in control SD rats. The EO content of serum, kidney and hypothalamus was significantly correlated with blood pressure in 1k1c hypertensive rats (r=0.59, 0.63, 0.52, respectively. P<0.05). The ouabain content of heart, liver, adrenal gland and pituitary was not correlated with blood pressure. Conclusions EO might play an important role in the development of hypertension in 1k1c hypertensive rats. The adrenal gland may be a major source of EO and the hypothalamus-pituitary-adrenal axis may be involved in the regulation of EO secretion. 相似文献
995.
Laminin(LN)isamajornoncollagenousglycoproteininbasementmembranesIthasbeenreportedthatLNcouldaffectanumberofbiologicbehaviorsofcarcinomacellsmediatedbytheLNreceptors1 ItisknownthattheNlinkedcomplextypecarbohydratechainsonLNareinvolvedintherecognitionan… 相似文献
996.
997.
小儿胆汁性腹膜炎27例诊断与治疗 总被引:1,自引:0,他引:1
目的 探讨小儿胆汁性腹膜炎的病因 ,提高小儿胆汁性腹膜炎的诊治水平。方法 对 2 7例小儿胆汁性腹膜炎的病因与诊治进行回顾分析。结果 2 7例中 17例手术中发现穿孔灶 ,行胆总管引流和腹腔引流 ,合并胆道扩张症作二期根治术 ;未明确穿孔灶 10例 ,作腹腔引流 ,合并胆道扩张症作一期根治术。无手术死亡及严重并发症 ,疗效满意。其中婴幼儿 6例 (2 2 .2 % ) ,儿童 2 1例 (77.8% )。病因多与胆总管囊肿 (6 2 .9% )、胆道结石与蛔虫 (7.4% )、经皮肝穿刺胆道造影 (PTC)损伤 (3 .7% )等有关 ,部分原因不明 (2 2 .2 % )。结论 小儿胆汁性腹膜炎容易误诊 ,掌握其临床特点、提高诊断意识及选择合适的手术方法 ,是提高早期诊断率和减少并发症的关键。 相似文献
998.
重组融合蛋白Fab/IFN-αA体外抗HBV作用的实验研究 总被引:1,自引:0,他引:1
目的 在体外细胞水平上观察重组融合蛋白(Fab/IFN-αA)对乙型肝为病毒(HBV)基因表达的抑制作用。方法 应用HBV DNA转染细胞系(HepG2.2.15细胞)作模型,通过固相放射免疫方法检测Fab/INF-αA作用后细胞上清液的HBsAg、HBeAg水平的变化,结合细胞存活率来评价其抗HBV作用,并与α-干扰素(IFN-αA)进行比较。结果 经12d作用,Fab/INF-αA在细胞存活率 相似文献
999.
探讨不同固定方式假体周围骨溶解X线征象差异与磨损颗粒迁移特点及其易聚积部位之间的联系 ,分析磨损颗粒在假体无菌性松动中的作用。方法 :观察因无菌性松动行翻修术的 39个国产人工髋关节术前X线片 ,按部位及固定方式分组统计假体周围不同区域衬性和膨胀性骨溶解的发生率 ,并测算溶骨带宽或溶骨面积。结果 :非骨水泥固定髋臼假体周围各区 (Delee分区法 )衬性骨溶解发生率明显高于骨水泥固定组 (P <0 0 5 ) ,溶骨带宽以三区最重 (P <0 0 5 )并大于骨水泥固定组对应区 (P <0 0 5 ) ;膨胀性骨溶解以三区发生率最高 (P <0 0 5 ) ,但两种固定方式各对应区之间发生率及溶骨面积均无显著性差异 (P >0 0 5 )。柄周衬性骨溶解宽度人工股骨头组除一、四区 (Gruen分区法 )、全髋关节组除三、四区无显著性差异 (P >0 .0 5 )外 ,其它各对应区均以骨水泥固定组较重 (P <0 .0 5 ) ;膨胀性骨溶解发生率以一、七区最高 (P <0 .0 5 ) ,两种固定方式各对应区之间溶骨面积差异无显著性意义 (P >0 .0 5 )。结论 :无菌性松动假体周围骨溶解的发生部位及严重程度与磨损颗粒迁移和聚集的部位有关 ,固定方式不同骨溶解的X线表现亦有差异。阻断磨损颗粒的扩散可能是防止骨溶解发生的有效方法之一。 相似文献
1000.