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21.
The prevalence of occult hepatitis B infection in HIV infected patients is controversial, varying from less than 1% to 62% in different studies. Blood samples of 111 HIV-infected patients, HCV-positive, HBs antigen negative, followed in the APROCO-ANRS EP11 cohort, were used to detect HBV DNA by using 2 different validated assays (Cobas Amplicor HBV Monitor Test and INSERM U271 qualitative ultra-sensitive PCR), completed when positive by HBV real-time PCR. HBV DNA was found in 6 (5.4%, 95% CI 1.2%-9.6%) patients by at least 1 of these assays, but none tested positive in all 3 assays. All 6 patients had anti-HBc without anti-HBs antibodies; 5 were not on lamivudine. Their median CD4 and CD8 counts were significantly lower and their HIV viral load higher than in the other 105 patients. In conclusion, the prevalence of occult hepatitis B may vary significantly according to the molecular assay used, even though these assays are validated with high specificity and quite high sensitivity. Occult hepatitis B may be encountered in HIV-HCV coinfected patients without anti-HBV treatment, with anti-HBc but without anti-HBs antibodies, and relatively low immunity, suggesting a potential risk of further reactivation, as already sporadically reported.  相似文献   
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BACKGROUND: Cardiovascular disease is a major cause of morbidity/mortality in non-developed countries. Reports of the effects of non-pharmacological interventions on global cardiovascular risk in Latin American adults, however, are scarce. OBJECTIVE: To compare the change in global cardiovascular risk induced by a tailored, Adult Treatment Panel-III compliant nutrition program versus the same program with addition of supervised, regular physical activity in Colombian adults. DESIGN: The study was a randomized, controlled trial. METHODS: Seventy-five Colombian patients aged 40-70 years and with Framingham-estimated global cardiovascular risk of 1% or higher were randomly assigned to a nutritional intervention program or a combined nutritional intervention-physical exercise program for 16 weeks. Patients underwent medical and anthropometric evaluation, bioelectrical impedance, lipid profile and Framingham global cardiovascular risk determination at baseline and at the end of follow-up. RESULTS: The groups were comparable at baseline; 21 persons in the nutritional intervention program group and 27 in the nutritional intervention-physical exercise program group completed the follow-up. Global cardiovascular risk modification (mean+/-SE) was -2.04+/-1.1 absolute percentage points (relative reduction 19.6%) in the nutritional intervention-physical exercise program group, compared with 0.23+/-0.9 (relative increase 2.8%) in the nutritional intervention program group. Mean difference in global cardiovascular risk modification between groups reached borderline statistical significance in ANCOVA (P=0.054). Reductions in systolic and diastolic blood pressure, waist circumference and low-density lipoprotein cholesterol were similar, but the nutritional intervention-physical exercise program group achieved significantly greater improvements in body weight, body mass index, percentage body fat and high-density lipoprotein cholesterol. CONCLUSIONS: Our data suggest that a structured nutritional intervention-physical exercise program is more efficacious than a nutritional intervention program in the reduction of global cardiovascular risk and cardiovascular risk factors, in only 16 weeks.  相似文献   
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Background

Hemophilia A (HA) is an X-linked inherited bleeding disorder, resulting from a qualitative or quantitative deficiency of clotting factor VIII (FVIII). Antibodies against FVIII, also called inhibitors, block the procoagulant activity of FVIII; thus, impairing hemostatic activity in patients with HA. The exact mechanism underlying the immunological events behind the development of inhibitors remains unknown. This study aimed to understand immune response to FVIII in patients with HA who were either positive [HAα-FVIII(+)] or negative [HAα-FVIII(−)] for inhibitors.

Methods

Cytokine profiles [interferon-γ (IFN − γ), tumor necrosis factor-α (TNF-α), interleukin-4 (IL-4), IL-5, and IL-10] of innate and adaptive immune cells present in the peripheral blood of participants were characterized.

Results

Presence of inhibitors was significantly associated with decreased frequencies of TNF-α-positive monocytes and neutrophils, IL-5-positive monocytes, IL-4-positive neutrophils, and increased frequencies of IL-10-positive neutrophils and T cells. T cells from HAα-FVIII(−) patients expressed increased levels of almost all cytokines. In contrast, HAα-FVIII(+) patients showed lower levels of all cytokines in CD4+ and CD8+ T cells, except IL-10. B cells from HAα-FVIII(−) patients expressed increased levels of IL-4 while those from HAα-FVIII(+) patients expressed increased levels of IL-10.

Conclusions

The global cytokine profiles of innate and adaptive immune cells showed an anti-inflammatory/regulatory pattern in HAα-FVIII(+) patients and a mixed pattern, with a bias toward inflammatory cytokine profile, in HAα-FVIII(−) patients. The occurrence of these profiles seems to be associated with presence FVIII inhibitors.  相似文献   
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阿莫西林钠中2-乙基己酸含量测定   总被引:2,自引:0,他引:2  
孙颖  韩锐 《黑龙江医药》2004,17(2):85-86
目的:建立一种气相色谱法测定原料药阿莫西林钠中二乙基己酸有机溶剂残留量。方法:选正戊酸作内标物,在极性弹性石英毛细柱上进行组分分离,效果良好。柱温:140℃进样口温度:200℃检测器温度:250℃。结果:平均回收率2-乙基己酸100.1%。结论:该方法克服了进样量不准确的缺点,重现性好,精度高。  相似文献   
28.
INTRODUCTION: Patients with albinism have varying degrees of reduced vision, strabismus, iris transillumination, nystagmus, fundus hypopigmentation, and foveal hypoplasia. High refractive errors are common, but reduced vision persists due to nonrefractive factors, causing reluctance by some clinicians to prescribe spectacles. We sought to evaluate the effect of spectacle correction of refractive error on clinical findings and recorded compliance with refractive corrections, as little detailed data exist. METHODS: We prospectively examined 35 consecutive patients with albinism for whom glasses had been prescribed to determine if objective improvement in recognition visual acuity (VA), strabismus, anomalous head posture (AHP), fusion, or stereoacuity occurred with refractive correction. Parents or patients reported compliance with glasses wear (excellent: >75% of awake hours; good: 50-75% of awake hours; fair: 26-50% of awake hours; poor: <25%). RESULTS: Median age was 9.5 years (range: 3 to 30). Median refractive correction was 1.875 D spherical equivalent (range: -9.75 to +8.88 D). Glasses wear was initiated at a median age of 14 months (range: 3 months to 14 years). Mean binocular VA at distance was 20/80.9 corrected and 20/107.6 uncorrected ( P < 0.001). Mean VA at near was 20/28.4 corrected and 20/41 uncorrected ( P < 0.001). Mean strabismic deviation was 7.2 PD with glasses and 10.0 PD without glasses at distance ( P = 0.006) and 10.8 PD with glasses and 14 PD without glasses at near ( P = 0.042). Mean AHP at distance was 8.3 degrees with glasses and 7.3 degrees without glasses at distance ( P = 0.327) and 4.7 degrees both with and without glasses at near ( P = 0.308). Twenty-one patients had fusion with or without glasses, two had fusion only with glasses, and one patient had fusion only without glasses. The other patients did not have any detectable degree of fusion. Twenty-seven individuals had no stereoacuity with or without glasses, five had gross stereoacuity of 3000 seconds of arc both with and without glasses, and three had gross stereoacuity only while wearing glasses. Compliance was excellent in 29 patients, fair in four, and poor in two. CONCLUSION: This prospective study showed a significant improvement in corrected VA and alignment in persons with albinism, despite overall subnormal acuity. Some individuals also experienced improvement in binocular alignment and AHP. Compliance with spectacles was generally good. Therefore, refractive correction should be encouraged in persons with albinism as improvement in visual function is likely to occur.  相似文献   
29.
In a retrospective study of proved pseudoaneurysms (PAs) in 15 patients with transplanted organs (11 liver, three kidney, one pancreas), the results of computed tomography (CT), duplex sonography, and angiography were reviewed. Of the 15 cases of PA, eight occurred at the arterial anastomosis and seven were nonanastomotic. Three of the eight anastomotic PAs were caused by infection. Of the seven nonanastomotic PAs, four were caused by percutaneous biopsy, two were caused by infection, and one was of undetermined cause. In nine (60%) of the 15 patients the PAs were incidentally detected at imaging studies performed for other reasons. Diagnosis requires a high degree of suspicion. CT was performed in nine cases and duplex sonography in ten. The diagnosis of PA was made with CT in six (67%) patients and with duplex sonography in five (50%). CT and duplex sonography could not enable diagnosis when the PA was small, when the arterial anastomosis was not included in the field of study, or when enhancement with intravenously administered contract material was suboptimal. Angiography depicted the PAs in all 15 patients. In three liver transplant recipients with gastrointestinal tract bleeding, the causative PAs were detected only with angiography.  相似文献   
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