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排序方式: 共有393条查询结果,搜索用时 31 毫秒
1.
背景与目的:原发性胆汁性肝硬化(PBC)伴系统性硬化症(SSc)的预后仍不十分清楚,该研究拟对其临床特点及预后进行评估。方法:从一个含580例患者的PBC数据库中选出43例PBC伴SSc患者,同时为每例PBC—SSc患者匹配2例单纯PBC患者作为对照,监测初次就医时的血清胆红素浓度。结果:局限皮肤型SSc者40例(93%)。诊断PBC时的中位年龄为49.7岁,胆红素浓度为17μmol/L,白蛋白水平为40.5g/L。24例(56%)患者于SSc后在中值为4.9年发生PBC。配对患者诊断PBC时的中位年龄为53.2岁、胆红素浓度为12μmol/L、白蛋白水平为41g/L。两组患者中位随访时间相似:PBC—SSc组为3.16年,单纯PBC组为4.8年。PBC—SSc患者南于较少接受移植手术(HR0.068;P:0.006),在校正性别、年龄、胆红素对数及碱性磷酸酶等因素后,其移植术或死亡风险(HR0.116;P=0.01)均明显降低,同时胆红素上升的比例亦较低(P=0.04)。 相似文献
2.
Visual pigments from the red rods of adults of eight species of Australian anuran amphibians, from a variety of habitats, were analyzed by microspectrophotometry. The lambda max in all cases fell between 502 nm and 506 nm, and the absorption spectra were well fitted by an A1-based visual pigment template curve. Red rod pigments were also analyzed for a number of tadpoles. In some cases the data were best fitted with an A1-based visual pigment template, in other cases with an A2-based template, and finally some tadpoles appeared to have mixtures of the two pigments. 相似文献
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Tacjana Pressler Gitte Kronborg Geoffry H. Shand Bendt Mansa Niels Høiby 《Medical microbiology and immunology》1992,181(6):339-349
IgG subclass antibodies to Pseudomonas aemginosa outer membrane proteins (OMP) were investigated in serum from cystic fibrosis (CF) patients by immunoblotting and enzyme-linked immunosorbent assay (ELISA). Fifteen patients (eight in good and seven in poor clinical condition) have been followed for an average of 13 years with multiple serum samples covering the preinfection, and early and late stages of chronic infection. Laser-scanning densitometry of photographs taken from immunoblots was used to quantify antibody level and compare with ELISA titres. The earliest anti-OMP antibodies to appear were of the IgG1 subclass. There was no significant difference in IgG subclass antibody levels to OMPs between patients in relatively good and poor clinical condition. Data presented indicate a high positive correlation among measurements of IgG subclass antibodies to P. aeruginosa OMPs using ELISA and immunoblotting. 相似文献
5.
Longitudinal study of antibody response to lipopolysaccharides during chronic Pseudomonas aeruginosa lung infection in cystic fibrosis. 总被引:5,自引:1,他引:5 下载免费PDF全文
Antibodies to Pseudomonas aeruginosa from 10 cystic fibrosis patients with chronic P. aeruginosa lung infections were quantitatively and qualitatively analyzed. The development of specific antibodies in patient serum was evaluated in a longitudinal study (1972 to 1987). The concentrations and specificities of immunoglobulin G (IgG) and IgM antibodies to purified lipopolysaccharides (LPS) from clinical isolates of P. aeruginosa and to a variety of other gram-negative bacteria were studied by immunoblotting and enzyme-linked immunosorbent assay techniques. Results were compared with the number of immunoprecipitates to P. aeruginosa whole-cell extracts detected by crossed immunoelectrophoresis. IgG, but not IgM, anti-Pseudomonas LPS concentrations increased significantly at the onset of chronic infection and continued to increase during the course of the infection. There was a good positive correlation between the concentration of IgG anti-Pseudomonas LPS antibodies and the number of crossed-immunoelectrophoresis precipitins. The increases in IgG anti-LPS antibody concentrations were much higher to Pseudomonas LPS than to other LPSs. Binding studies demonstrated an increase in binding of IgG anti-Pseudomonas LPS during infection, whereas the binding of other anti-LPS antibodies decreased. Immunoblotting studies confirmed that antibodies reacted strongly with Pseudomonas LPS and weakly with Escherichia coli core-lipid A. The specificity of the reaction with Pseudomonas LPS increased with the duration of infection. It is concluded that anti-LPS response in cystic fibrosis patients during chronic P. aeruginosa infection demonstrates a marked increase in IgG anti-Pseudomonas LPS antibody concentration, specificity, and affinity. The anti-LPS enzyme-linked immunosorbent assay is proposed as a routine test to diagnose and to follow the course of chronic P. aeruginosa lung infection in patients with cystic fibrosis. 相似文献
6.
Serum samples collected over periods up to 15 years from nine patients with cystic fibrosis (CF) were investigated by immunoblotting and crossed immuno-electrophoresis (CIE) for antibodies to Pseudomonas aeruginosa outer-membrane proteins (OMPs). The earliest antibody response to OMPs was directed against proteins G, H1 and I. Detection by immunoblotting sometimes preceded the CIE response; the appearance of antibodies to the other major OMPs was co-incident with an increase in CIE precipitins. Isolation of the mucoid form of P. aeruginosa was associated with a rapid increase in both precipitin numbers and antibodies detected by immunoblotting. Antibodies to iron-regulated OMPs could be detected in all the serum samples that showed eight or more CIE precipitins but their presence became pronounced only in the advanced stages of disease. The clinical strain used in this study and other isolates from CF patients showed several atypical OMPs, perhaps as a consequence of antibiotic therapy or related to the serum sensitivity of mucoid P. aeruginosa. Their expression in vivo was confirmed by detecting antibodies to them in patients' serum. 相似文献
7.
Female CBA/H-T6T6 mice were given daily i.p. injections of 1 ml of saline containing 250 mg of human serum albumin (HSA) for 7 consecutive days. Control mice received the same volume of saline only. At approximately 24 hourly intervals for the 10 days after the first injection, groups of mice (3 HSA and 1 saline-injected) were killed and kidney tissue was taken for light (LM) scanning (SEM) and transmission (TEM) electron microscopy. Small numbers of glomeruli with Bowman''s space filled with protein and fine, radially-disposed casts in collecting tubules were observed by LM. SEM revealed focal changes in both endothelium and epithelium, and in a few cases severely damaged epithelial cells were seen. TEM showed numerous small regions of loss or change in shape of foot processes. Epithelial cell branches became increasingly swollen. By the third day after the last injection glomerular morphology appeared to have returned to normal. Although the cause of the proteinuria was attributed to the effects of HSA-induced increased blood viscosity, the focal distribution of the observed morphological changes remains unexplained. 相似文献
8.
Matthiessen's ratio (distance from centre of lens to retina:lens radius) was measured in developing black bream, Acanthopagrus butcheri (Sparidae, Teleostei). The value decreased over the first 10 days post-hatch from 3.6 to 2.3 along the nasal and from four to 2.6 along temporal axis. Coincidentally, there was a decrease in the focal ratio of the lens (focal length:lens radius). Morphologically, the accommodatory retractor lentis muscle appeared to become functional between 10-12 days post-hatch. The results suggest that a higher focal ratio compensates for the relatively high Matthiessen's ratio brought about by constraints of small eye size during early development. Combined with differences in axial length, this provides a means for larval fish to focus images from different distances prior to the ability to accommodate. 相似文献
9.
慢性乙型肝炎患者中医证型与肝脏病理改变及血清转化生长因子β_1相关性研究 总被引:7,自引:0,他引:7
目的 探讨慢性乙型肝炎患者中医辨证分型与肝脏病理改变及血清转化生长因子(TGF) β1含量的关系。方法 对92例慢性乙型肝炎患者进行肝组织病理诊断和中医分型。采用酶联免疫吸附试验(ELISA)测定92例患者血清TGF β1。结果 ①92例患者病理分型,轻度6 5例,中度19例,重度8例;②92例患者中医分型为肝郁脾虚型4 9例,湿热中阻型3例,肝肾阴虚型11例,脾肾阳虚型6例,瘀血阻络型2 3例;③病理分型轻度者以肝郁脾虚型为主(72 % ) ,中度者瘀血阻络型占6 3% ,重度者8例均为瘀血阻络型;④肝郁脾虚型者血清TGF β1含量最低,肝内纤维化程度轻;瘀血阻络型患者血清TGF β1含量最多,肝内纤维化程度最重(P <0 .0 1) ,其余3型介于两者之间,血清TGF β1含量差异无统计学意义(P >0 . 0 5 )。结论 慢性乙型肝炎以肝郁脾虚型为主,随着肝损害加重,瘀血阻络型逐渐增加。因此,对慢性乙型肝炎轻度者要注重疏肝健脾,对中、重度者要注意活血化瘀 相似文献
10.