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1.
IFN-γ和糖皮质激素对哮喘病人T淋巴细胞中的TGF-β的作用   总被引:1,自引:0,他引:1  
目的:探讨C D4 TG F-β,C D8 TG F-β在哮喘发病机制中的作用,了解IFN-γ和糖皮质激素对其的影响。方法:采用Ficoll-H ypague密度梯度离心及贴壁培养法对18例哮喘患者和10例健康对照者外周血单个核细胞进行分离,纯化后,加入地塞米松及IFN-γ培养24h,加入PM A,莫能菌素,艾罗霉素培养4.5h,促使细胞内细胞因子聚集于高尔基体,取培养上清中的淋巴细胞经流式细胞仪检测分析C D4 T、C D8 T淋巴细胞及其细胞内细胞因子TG F-β表达率。结果:C D4 TG F-β、C D8 TG F-β及C D4、C D8细胞内总TG F-β检测结果的比较,哮喘组C D4 TG F-β(15.50±0.15)%、C D8 TG F-β(19.34±0.18)%,与正常对照组(9.57±0.16)%、(13.49±0.26)%比较,显著增高(均P<0.05);加入地塞米松培养的哮喘组C D4 TG F-β,C D8 TG F-β无显著变化(P>0.05),加入IFN-γ培养的哮喘组C D4 TG F-β(7.61±0.09)%、C D8 TG F-β(9.82±0.19)%的变化显著降低(均P<0.05),C D4、CD8细胞内总TG F-β哮喘组(32.42±1.17)%比正常组(20.53±1.02)%显著增加(P<0.05),加地塞米松后无显著变化(P>0.05),加IFN-γ后(16.85±0.14)%,显著降低(P<0.05)。结论:哮喘急性发作期有C D4 TG F-β、C D8 TG F-β升高;地塞米松不能降低哮喘气道重塑;IFN-γ可通过抑制TG F-β的分泌治疗哮喘,降低哮喘气道重塑。  相似文献   
2.
ABSTRACT. Hultcrantz R, Angelin B, Einarsson K, Friman L (Departments of Internal Medicine and Roentgenology, Serafimer Hospital, and Department of Internal Medicine, Huddinge University Hospital, Karolinska Institute, Stockholm, Sweden). Spontaneous regression of Budd-Chiari syndrome (hepatic venous occlusion) in a young female. Acta Med Scand 1987; 221:503–7. A case of occlusion of the hepatic veins in an 18-year-old girl is presented. The onset was sudden with massive ascites and markedly impaired general condition. The diagnosis was based on liver biopsy and angiograms of the caval and hepatic veins as well as of the celiac artery. No predisposing factors could be found. The patient was treated conservatively with laparo-centesis and diuretics. Clear improvement was seen after two weeks, and after four weeks she had no ascites and could be discharged. All liver function tests were then normalized. After three months, all diuretics could be withdrawn, and in the following 11 years she has remained completely recovered. The case illustrates that also widespread thrombi of the hepatic veins may sometimes rapidly dissolve spontaneously, with apparent total reconstitution of hepatic function. This case is unusual since previously reported cases have had high mortality rates and, in surviving cases, operative procedures or large doses of diuretics have been required to control the ascites.  相似文献   
3.
AIM: To evaluate the cause of elevated prostate-specific antigen (PSA) in patients with transrectal needle biopsy negative for prostate cancer. METHODS: Serum PSA concentration, prostate volume, and pathologic findings were examined in 223 patients with negative biopsy for prostate cancer. The degree of prostate inflammation was determined by the extent and degree of inflammation shown by biopsy specimens and is expressed as an inflammation score (range: 0-36). RESULTS: A significant correlation was found between PSA concentration and prostate total volume (P=0.0001). Prostate chronic inflammation showed no correlation with PSA concentration (P=0.485, F=0.488). After allocating patients to normal PSA (4 ng/mL) groups, we found that serum PSA concentrations in both groups were predominantly affected by prostate total volume. CONCLUSIONS: An increase in prostate volume appears to be the major contributor to a high serum PSA concentration in patients with negative biopsy for prostate cancer. However, in contrast to previous reports, there was no correlation between the degree of prostate chronic inflammation and serum PSA concentrations.  相似文献   
4.
NATURE AND HEALING OF TIBIAL SHAFT FRACTURES IN ALCOHOL ABUSERS   总被引:3,自引:1,他引:2  
Alcohol abuse is associated with an increased risk of osteopeniaand fractures. Previous histomorphometric studies on iliac crestbone have found decreased bone formation and increased boneresorption in alcohol abusers but it has not been establishedwhether alcohol abuse has any effect on the anatomical locationor the healing time of tibial shaft fractures. We studied, retrospectively,199 adult male patients hospitalized for isolated tibial shaftfracture in the city of Malmö, Sweden, between 1980 and1990. Forty-nine of the patients had earlier been registeredat the Department of Alcohol Diseases and were judged to beproblem drinkers. Abusers sustained their tibial shaft fracturesmore often by falling at ground level (P<0.0001) or froma higher level (P=0.009) and the fractures were more often obliquethan transverse (P=0.002) as compared with non-abusers. Healingtime was impaired in abusers who had sustained a transversefracture (P=0.035), but no difference was observed in healingtime in those with an oblique fracture. We found no differencebetween the abusers and the non-abusers regarding duration ofhospital stay, fracture location, amount of displacement, occurrenceof open fractures or the rate of complications.  相似文献   
5.
本文报告应用国产法莫替丁治疗消化性溃疡45例的近期疗效。治疗组法莫替丁20mg,早晚各服一次;对照组甲氰咪胍400mg,早晚各服一次,两组疗程皆为6周。以胃镜检查为诊断和评价疗效的依据,两组愈合率分别为97.8%,89.9%,上腹疼痛用药后三日缓解率分别为60.9%,30.2%。两组均未出现明显毒副作用,由于抗溃疡新药疗效高,提示今后治疗无合并症消化性溃疡将以药物治疗为主。  相似文献   
6.
Abstract: Polycythaemia vera (PV) is a myeloproliferative disorder characterized by haematopoietic progenitor cells being hypersensitive to cytokines such as erythropoietin, interleukin-3, stem cell factor and insulin-like growth factor 1, which results in an increased production of mature blood cells. The pathogenetic cellular mechanism(s) behind this hypersensitivity to cytokines is unknown, but the number of cytokine receptors and the interaction between ligand and receptor are normal in PV. Interest has therefore focused on post-receptor mechanism(s). Haematopoietic cell phosphatase (HCP) is an intracellular tyrosine phosphatase that has been demonstrated to regulate proliferative signals negatively induced by the cytokines mentioned above. Moreover, motheaten mice that genetically lack HCP have an increased amount of erythroid progenitors that are hypersensitive to Epo, and patients with familial polycythaemia have been shown to exhibit a mutation of the Epo receptor gene that includes the docking site for HCP. We therefore studied mRNA expression of HCP in pure populations of CD34+ cells, granulocytes, platelets and lymphocytes from patients with PV, chronic myeloid leukaemia (CML) or essential thrombocythemia (ET), as well as healthy controls. Using a polymerase chain reaction analysis employing specific primers for HCP, we failed to detect any abnormalities of HCP expression in PV in any of the cell populations that were examined. Moreover, HCP mRNA expression was similar in ET and CML compared to controls. Finally, Western blot analysis revealed a normal HCP protein content in PV granulocytes and platelets. We therefore conclude that neither an impaired expression of the HCP gene nor a defect in HCP protein synthesis is present in PV, and does not seem to play a role in the aetiology of this disorder.  相似文献   
7.
Dural sinus thrombosis: study using intermediate field strength MR imaging   总被引:1,自引:0,他引:1  
The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus.  相似文献   
8.
A car-borne NaI(Tl) spectrometric system was used together with a 137Cs source to obtain realistic data in the search for unshielded and semi-shielded orphan sources. The potassium-stripped counts (PSC) method was used to estimate the influence by the shielding on the detection ability. A reduction of about 5% in the critical distance was obtained for the semi-shielded source. A curve fitting method was also developed and evaluated. Results from the curve fitting method showed inferior ability to find the source compared to the PSC method. However, it can be a useful complementary tool, for characterisation of the source shielding, and estimation of the distance from the road.  相似文献   
9.
Lewis Histo-Blood Group System and Associated Secretory Phenotypes   总被引:6,自引:0,他引:6  
This review summarises present knowledge of the chemistry, immunology, genetics and clinical significance of antibodies in the Lewis and secretor histoblood group systems. Although red cell serology has laid the foundations for these systems, more recent advances have been made by studying Lewis and related glycoconjugates with monoclonal antibodies, determining structures by mass spectrometry and NMR spectroscopy, identifying enzymes and their specificities, and identifying the genes by molecular biology. The expression of Lewis system antigens is dependent on Lewis and secretor loci. Fucosyltransferases coded by genes at these loci compete and interact with each other and with other transferases to determine an individual's Lewis and secretor phenotype. Exocrine epithelial cells, mostly of endodermal origin, synthesise the Lewis antigens which, as plasma glycolipids, are secondarily acquired by cells of the peripheral circulation. Phenotyping red cells is often regarded as a simple way of determining the Lewis and sometimes the secretor status of an individual; however, the red cell phenotype is influenced by many factors and may not necessarily reflect someone's Lewis and secretor genotypes. Two main red cell Lewis groups are usually found, Lewis negative and Lewis positive. In Lewis-negative individuals, the secretor genotype does not affect the Lewis phenotype, but in Lewis-positive individuals, the non-secretor genotype generates the Le(a+b–) phenotype, the secretor genotype causes the Le(a–b+) phenotype, and the partial secretor genotype gives rise to the Le(a+b+) phenotype.  相似文献   
10.
S M Samuelsson  A Ekbom  M Zack  C G Helmick    H O Adami 《Gut》1991,32(12):1526-1530
To examine socioeconomic factors, dietary and other personal habits, and medical history as risk factors for ulcerative colitis, we studied 167 (98%) of all prevalent cases of ulcerative colitis diagnosed in Uppsala county from 1945 to 1964 and 167 age and sex matched population controls. Ulcerative colitis patients were less likely than controls to be current cigarette, pipe, or cigar smokers (odds ratio (OR) = 0.44; 95% confidence limits (CL) = 0.25-0.78), but more likely to have symptoms induced by drinking milk (OR = 4.63; 95% CL = 2.15-9.93). Patients with ulcerative colitis do not differ in most of the socioeconomic, dietary and personal habits compared with the background population.  相似文献   
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