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71.
72.
Abstract: In this study we characterized the haplotypes found in IDDM patients that normally confer resistance to the disease in order to localize the polymorphisms relevant for the protection. We studied 15 DR2-positive subjects with IDDM for their DRB1, DRB5 and DQB1 genes using RFLP, polymerase chain reaction (PCR), oligonucleotide typing, and in some specific cases direct sequencing after allele-specific PCR. In addition we analyzed 39 DR2-positive, IDDM non-associated haplotypes representing those haplotypes that are not inherited to probands and hence are present only in healthy family members. The frequency of the DRB1*1501-DRB5*0101-DQB1*0602 haplotype was slightly decreased among diabetic patients (80% vs. 92%). In addition, two unconventional haplotypes DRB1*1501-DRB5*0101-DQB1*05031 and DRB1*1501-DRB5*0101-DQB1*0502 were found in patients with IDDM while all the control ones were conventional. The sequencing of the DQB1*0602 allele present in IDDM haplotypes showed no differences when compared to the controls. These results support the primary but not absolute role of DQ in the protection against IDDM. An additional role of factors centromeric to DQB1 gene was suggested by findings based on the biallelic TaqI RFLP polymorphism of the DQA2 gene. All DR2-DQB1*0602 IDDM haplotypes were associated with the 2.1-kb fragment while in the control group the 2.1-kb and 1.9-kb fragments were evenly distributed.  相似文献   
73.
The effects of vitamin A, pentoxyfylline and methylprednisolone on experimentally induced amyloid arthropathy were investigated. In this study, 175 1-day-old brown layer chicks were used. Throughout the study Group II (vitamin A) received high doses of vitamin A (75,000 IU/kg), whereas Group I (negative control), Group III (positive control), Group IV (pentoxyfylline) and Group V (methylprednisolone) received normal levels of vitamin A in the diet. At the fifth week, the experimental Groups II, III, IV and V were injected with Freund's adjuvant intra-articularly to induce amyloid arthropathy. Group IV received pentoxyfylline and Group V received methylprednisolone (10 mg/kg, intramuscularly) once. Joint and blood samples were examined 13 weeks after the injections. The values in Groups I, II, III, IV and V, respectively, were as follows: amyloid arthropathy formation (%), 0, 100, 87, 76, 66; serum amyloid A (ng/ml), 166+/-17, 607+/-40, 423+/-39, 342+/-27, 293+/-22; serum retinol (microg/dl): 59.75+/-3.8, 42.72+/-3, 59.24+/-3.6, 102+/-9.1, 101.3+/-12.3; heterophil/lymphocyte ratio: 0.504, 0.75, 0.75, 0.087, 0.44. In conclusion, it was observed that vitamin A enhanced the development of amyloid arthropathy and there were positive associations between amyloidosis, increased levels of serum amyloid A and increased numbers of tissue infiltrating macrophages. Methylprednisolone had a more successful inhibitory effect on amyloid arthropathy than pentoxyfylline.  相似文献   
74.
BACKGROUND: Patients with hypertension and renal-artery stenosis are often treated with percutaneous transluminal renal angioplasty. However, the long-term effects of this procedure on blood pressure are not well understood. METHODS: We randomly assigned 106 patients with hypertension who had atherosclerotic renal-artery stenosis (defined as a decrease in luminal diameter of 50 percent or more) and a serum creatinine concentration of 2.3 mg per deciliter (200 micromol per liter) or less to undergo percutaneous transluminal renal angioplasty or to receive drug therapy. To be included, patients also had to have a diastolic blood pressure of 95 mm Hg or higher despite treatment with two antihypertensive drugs or an increase of at least 0.2 mg per deciliter (20 micromol per liter) in the serum creatinine concentration during treatment with an angiotensin-converting-enzyme inhibitor. Blood pressure, doses of antihypertensive drugs, and renal function were assessed at 3 and 12 months, and patency of the renal artery was assessed at 12 months. RESULTS: At base line, the mean (+/-SD) systolic and diastolic blood pressures were 179+/-25 and 104+/-10 mm Hg, respectively, in the angioplasty group and 180+/-23 and 103+/-8 mm Hg, respectively, in the drug-therapy group. At three months, the blood pressures were similar in the two groups (169+/-28 and 99+/-12 mm Hg, respectively, in the 56 patients in the angioplasty group and 176+/-31 and 101+/-14 mm Hg, respectively, in the 50 patients in the drug-therapy group; P=0.25 for the comparison of systolic pressure and P=0.36 for the comparison of diastolic pressure between the two groups); at the time, patients in the angioplasty group were taking 2.1+/-1.3 defined daily doses of medication and those in the drug-therapy group were taking 3.2+/-1.5 daily doses (P<0.001). In the drug-therapy group, 22 patients underwent balloon angioplasty after three months because of persistent hypertension despite treatment with three or more drugs or because of a deterioration in renal function. According to intention-to-treat analysis, at 12 months, there were no significant differences between the angioplasty and drug-therapy groups in systolic and diastolic blood pressures, daily drug doses, or renal function. CONCLUSIONS: In the treatment of patients with hypertension and renal-artery stenosis, angioplasty has little advantage over antihypertensive-drug therapy.  相似文献   
75.
OBJECTIVE: To delineate the influence of hormone therapy (HT) on features of metabolic syndrome with special reference to the composition and mode of administration of three specific HT regimens, all containing estradiol (E2) + norethisterone. DESIGN: The Women's Health in the Lund Area project screened all women (n = 10,766), born between 1935 and 1945. Complete data were obtained from 6,917 women. Those at or above defined cutoff limits were considered positively screened (n = 3,593) for metabolic syndrome. All of them were invited to undergo an oral glucose tolerance test; 2,923 women accepted. After excluding 200 women with impaired fasting glucose, 2,723 women were included in the present analysis. Serum lipids were determined by conventional standard methods at the department of clinical chemistry of Lund University Hospital. RESULTS: According to World Health Organization criteria, 2,123 women had normal glucose tolerance and 600 women had impaired glucose tolerance (IGT). IGT was less common (P = 0.001) among users of a transdermal patch [CYC-TRANS; E2 50 microg + norethisterone acetate (NETA) 250microg] compared with the two-combined oral regimen [CON-O (continuous oral E2 2 mg + NETA 1 mg) + CYC-O (sequential oral E2 2 mg + NETA 1 mg)]. Furthermore, IGT was more common among CON-O users when compared with either the CYC-O + CYC-TRANS group (P = 0.002) or the CYC-TRANS only group (P = 0.001). There were no significant differences between CYC-O versus CYC-TRANS or CON-O. Serum levels of total cholesterol were higher in the CYC-TRANS group than in the combined CON-O + CYC-O group (P < 0.05); they also were higher (P = 0.05) when comparing the CYC-O + CYC-TRANS versus CON-O as well as higher in CYC-TRANS versus CON-O (P < 0.05). Serum high-density lipoprotein cholesterol levels were higher in the CYC-O (P = 0.001), CYC-TRANS (P < 0.05), and the CYC-O + CYC-TRANS (P = 0.001) groups when compared with the CON-O users. There were no differences in the mean age, blood pressure (systolic and diastolic), body mass index, waste-hip ratio, or the rate of cigarette and alcohol consumption between the different hormone regimens. CONCLUSION: The risk of having a pathological glucose load was lower in transdermal versus oral users of HT. Transdermal HT could be regarded as first-line treatment in women at risk of developing diabetes.  相似文献   
76.
The long intracellular half-life of abacavir (ABC) supports its once-daily use, and this would be expected to simplify treatment if ABC could be given as part of a complete once-daily regimen. A randomized double-blind clinical trial compared the efficacy and safety of 600 mg of ABC administered once daily (n = 384) versus 300 mg of ABC administered twice daily (n = 386) in combination with 300 mg of lamivudine (3TC) and 600 mg of efavirenz (EFV) administered once daily in antiretroviral-naive patients over 48 weeks. The baseline median plasma HIV-1 RNA level was 4.89 log10 copies/mL (44% with viral load >100,000 copies/mL), and the median CD4 cell count was 262 cells/mm. ABC administered once daily was non-inferior to the twice-daily regimen, with 66% and 68% of patients in these respective treatment arms achieving a confirmed plasma HIV-1 RNA level <50 copies/mL (95% confidence interval: -8.4%, 4.9%). The ABC once-daily and twice-daily regimens were similar with respect to infrequency of virologic failure (10% vs. 8%), emergence of resistance mutations, CD4 cell increases from baseline (median, 188 vs. 200 cells/mm), safety profile, and incidence of ABC-related hypersensitivity reactions (9% vs. 7%). ABC administered once daily in combination with 3TC and EFV administered once daily was non-inferior to the ABC twice-daily dosing schedule when combined with 3TC and EFV over 48 weeks.  相似文献   
77.
The radial nerve's course from the axillary region, branch patterns and the relation of the nerve to fixed anatomical landmarks in the arm region were studied in 27 embalmed intact cadavers. The radial nerve and its relation with the sulcus nervus radialis (SNR) was analyzed. The direct contact of the nerve with humerus in SNR was observed during the dissections. The following measurements were made: the total length of the humerus (the palpable uppermost point of the tuberculum majus and the lateral epicondyle); proximal safe zone (the tuberculum majus and the proximal beginning of the SNR); distal safe zone (the intercondylar axis and the middle of SNR); lateral safe zone (the lateral epicondyle and the distal end of SNR). In conclusion, it was aimed to correlate the osseus palpable landmarks of humerus with the course of the radial nerve for a safe surgery as the sulcus nervi radialis region is one of the main risky areas for the radial nerve palsies.  相似文献   
78.
李品兰 《中国免疫学杂志》1990,6(6):338-340,352
用不同浓度的IL-2刺激静息T淋巴细胞,其细胞内IP_3无明显改变,但ConA刺激则使IP_3增加45%。在IL-2依赖性T细胞,IL-2R表达率达83%,IL-2刺激时IP_3的变化依浓度不同而异,10u—50u/ml的IL-2使IP_3增高,以50u/ml最为显著,增加60%,但100u/ml IL-2及ConA不改变胞内IP_3的浓度。IL-2R封闭后的T淋巴细胞在IL-2刺激时IP_3的增加明显减弱。这些结果提示:IP_3作为细胞内的第二信使介导了IL-2诱导的T细胞的增殖反应,这种作用与IL-2的剂量及IL-2R表达有密切的关系。  相似文献   
79.
CD4 is a candidate gene in autoimmune diseases, including Type 1 diabetes mellitus (T1DM), because the CD4 receptor is crucial for appropriate antigen responses of CD4(+) T cells. We previously found linkage between a CD4-1188(TTTTC)(5-14) promoter polymorphism and T1DM. In the present study, we screened the human CD4 promoter for mutations and identified three frequent single nucleotide polymorphisms (SNPs): CD4-181C/G, CD4-521C/G and CD4-1050T/C. The SNPs are in strong linkage disequilibrium (LD) and association with the CD4-1188(TTTTC)(5-14) alleles, and we observed nine CD4 promoter haplotypes, of which four are frequent. We genotyped the SNPs in 253 Danish T1DM families (1129 individuals) and found evidence for linkage and association of a CD4 (A4(-1188)T(-1050)G(-521)C(-181)) haplotype to T1DM. In reporter studies, we show that (1) the T1DM-associated CD4 haplotype encodes high constitutive promoter activity and (2) the CD4-181G variant encodes higher stimulated promoter activity than the CD4-181C variant. This difference is in part neutralized in the frequently occurring CD4 promoter haplotypes by the more upstream genetic variants. Thus, we report functional impact of a novel CD4-181C/G SNP on stimulated CD4 promoter activity and the identification of a novel CD4 haplotype with high constitutive promoter activity that is linked and associated with T1DM.  相似文献   
80.
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