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41.
Crude total antigen (CTA) from Leishmania infantum and recombinant antigen K39 (rK39) and recombinant antigen K28 (rK28) were compared using an ELISA for the diagnosis of canine visceral leishmaniosis (CVL). Forty‐two blood samples from healthy dogs from a nonendemic area and 80 blood samples from an endemic area for dogs with visceral leishmaniosis (VL), confirmed with positive parasitological tests for Leishmania spp., were used in an ELISA. The parasitological diagnosis was chosen as a gold standard. The ELISA with rK28 antigen showed sensitivity of 100% and specificity of 100%, high agreement with CTA and rK39, indicating that the rK28 antigen is useful for ELISA serological diagnosis of CVL.  相似文献   
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The adverse effect of disease and chronic corticosteroid therapy on bone mineral density (BMD) in patients with systemic lupus erythematosus (SLE) has been reported in several studies of Caucasian populations. As the factors controlling bone homeostasis may be different in Asian populations, we measured BMD in 52 pre-menopausal Chinese women (mean age 34.1 +/- 8.0 yr) with SLE (mean disease duration 6.4 +/- 4.5 yr) treated with prednisone (mean daily dose 11.4 +/- 10.8 mg/day). Lumbar spine, hip (total and subregions) and total body BMDs were measured in the SLE patients using dual-energy X-ray absorptiometry (DEXA), and compared with those from healthy controls matched for age, sex and body mass index. Compared to controls, SLE patients were found to have lower BMD (g/cm2) at several sites: the lumbar spine (0.98 vs 0.90, P = 0.001), Ward's triangle (0.72 vs 0.67, P = 0.03), total body (1.04 vs 1.01, P = 0.04) and total hip (0.87 vs 0.82, P = 0.05). There was no correlation between BMD at any region and duration of disease, activity of disease or prednisone therapy (mean daily dose, cumulative dose or treatment duration). When BMDs were compared between controls and SLE patients, subgrouped according to those not on calcium and those arbitrarily receiving calcium supplements (1 g/day), significantly lower BMDs were found in those not on calcium compared to both controls and SLE patients on calcium. BMDs in SLE patients on calcium were not different from those in controls. The low prevalence of osteoporosis in our SLE patients (4-6%) suggests significant loss of BMD in Chinese SLE patients on corticosteroid therapy is less than that reported in Caucasians (12-18%).   相似文献   
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The aim of this study was to evaluate the effect of exercise on pregnancy outcome in streptozotocin-induced diabetic Wistar rats (n = 11 animals/group). These animals were randomly assigned to sedentary (G1) and exercised groups, beginning from day 0 (G2) or 7 (G3) to day 20 of pregnancy. The moderate exercise was a swimming programme. At day 21 of pregnancy, all rats were anaesthetized and killed to obtain pregnancy outcome data. All rats presented glycaemia higher than 300 mg/dl, regardless of the exercise training. The G3 group showed higher live fetus number per implantation site and lower resorption number per implantation site compared with the G1 group. The fetal and placental mean weights per litter and the total number of ossification sites were significantly lower in the exercised groups (P < 0.05). Placental index was lower in the G2 and G3 groups compared with the G1 group. The occurrence of skeletal anomalies indicated that exercise increased the number of altered fetuses. Thus, moderate exercise achieved better outcomes by increasing the number of live births and decreasing resorption. However, exercise increased skeletal anomalies and decreased fetal and placental weights.  相似文献   
46.
The random-effects model applied to refractory ceramic fiber data   总被引:1,自引:0,他引:1  
Refractory ceramic fiber (RCF) is a valuable, high-temperature, insulating material with a variety of industrial uses. Because some fibers are respirable by humans and RCF is relatively durable in simulated lung fluids, RCF may pose a health hazard in the workplace. The RCF industry has established a comprehensive product stewardship program (PSP) to identify, quantify, and manage risks. One key element of this PSP is a workplace monitoring program. This paper analyzes monitoring data collected as part of a Consent Agreement with the U.S. Environmental Protection Agency over the period from 1993 to 1998. More specifically, this paper applies the random-effects model (REM) to data collected at several Unifrax plants and applicable to several groups of workers. The REM fits the RCF data well. Depending upon the plant and the functional job category values of the variance of the log-transformed time-weighted average workplace concentrations range from slightly less than 0.5 to 1.0. The estimated intraclass correlations (ratio of the between-worker variance to the total variance) were less than 0.4, and most were less than 0.2. Implications of these findings are examined. Use of the REM in the development of a workplace respiratory policy is described. Finally, two possible criteria for measuring compliance with an occupational exposure limit are reviewed: an "overexposure" criterion developed by Rappaport and co-workers and a conventional "no exceedance" criterion reportedly used by regulatory agencies. The overexposure criterion is logically correct for potential toxicants with chronic effects. For representative values of statistical parameters for RCF from the plants considered, the overexposure criterion is less stringent.  相似文献   
47.
Green tea polyphenols have been shown to inhibit cancer in a variety of tumor models, including ultraviolet B (UVB)-induced non-melanoma skin cancer. In green tea extracts, the major dry mass constituent is the family of catechins, of which (-)-epigallocatechin-(3)-gallate (EGCG) is considered to be important for the chemopreventive activity. EGCG has been shown to have antioxidant properties, but there has been little progress toward identifying the specific targets and mechanisms of its action. Using cultured human keratinocytes, we show that UVB- induced AP-1 activity is inhibited by EGCG in a dose range of 5.45 nM to 54.5 microM. EGCG is effective at inhibiting AP-1 activity when applied before, after or both before and after UVB irradiation. EGCG also inhibits AP-1 activity in the epidermis of a transgenic mouse model. This work begins to define a mechanism by which EGCG could be acting to inhibit UVB-induced tumor formation.   相似文献   
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去甲斑蝥酸钠白蛋白微球的研究   总被引:5,自引:0,他引:5  
选择去甲斑蝥酸钠为模型药物,对含药白蛋白微球的制备、载药性能、形态、表面状态、大小及分布、体外释药、冷冻干燥、60Co辐照灭菌和稳定性等进行了研究。结果表明,去甲斑蝥酸钠微球的平均大小为0.43±0.12μm,药物含量为20.34~26.75μg/ml,包入率21.9~26.4%,体外释药符合Higuchi方程,冷冻干燥和60Co辐照对微球无影响且能达到无菌要求,放置3个月后微球的稳定性良好。  相似文献   
50.
颈外动脉栓塞用顺铂白蛋白微球的研究   总被引:3,自引:0,他引:3  
用乳化化学交联法制备出适合于颌面部鳞癌殒外动脉栓塞用顺铂白蛋白微球;外观呈黄色粉末状,收率80±5%,显微观察呈圆球体,平场粒径56.3μm:药物含量为14.02~14.2%,包封率97.08~97.95%。对其体外释药、灭菌、稳定性及分散溶媒的处方进行了探讨。通过动物实验表明该微球可以达到理想的栓塞效果,并保证能在局部组织停留,有利于提高抗癌药物的疗效,降低毒副作用。  相似文献   
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