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1.
The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005, in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a priority area for studies on this zoonosis. Given this, the present study provides data on this phenomenon in an urban context, in order to assess the possible circulation of the classic rabies virus (RABV) among bat species in Capanema, a town in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and dry seasons. Samples of brain tissue and blood were collected for virological and serological survey, respectively. None of the 153 brain tissue samples analyzed tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum samples analyzed were seropositive. Artibeus planirostris was the most common species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31 52.60%). Statistically, equal proportions of seropositive results were obtained in the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95% CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested positive for infection, the high proportion of seropositive specimens indicates that RABV may be widespread in this urban area.  相似文献   
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背景:Sauvegrain方法是通过分析肘部X线片来评估骨龄,常用于青春期生长发育最为迅速的两年间的骨龄测定。本文旨在研究该方法的准确性以及在小儿骨科中的应用价值。 方法:Sauvegrmn法主要评估肘部的4个解剖标志点:外髁、肱骨滑车、尺骨鹰嘴突以及桡骨近端骨骺。它是一个27分制的评分系统。对上述结构所得的评分进行合计而得出一个总分,然后使用标准图表确定骨龄。让三位观察者分别利用该方法进行骨龄评估。三位观察者通过分析60个男孩和60个女孩样本左肘部的前后位和侧位X线片来测定骨龄,并将该结果与通过分析左手和腕部后前位X线片的Greulich和Pyle图谱而得出的骨龄结果进行比较。间隔4周后每个观察者再测定骨龄一次。 结果:通过分析肘部X线片的方法测定骨龄更为精确,因为采用该方法测定骨龄可以精确到半岁。根据观察者的评定,Sauvegrain法显示出很好的观察者之间的相关性(r=0.93)和可重复性(r=0.96)。Sauvegrain法与Greulich和Pyle图谱之间有很好的相关性(r=0.85)。然而,一些肘部生长中心显示出一种中间的发育形态,这种形态学不适合Sauvegrain法的评分。这就导致了数据分析时出现误差。我们建议对于这些样本设定中间评分,并且通过修改原始图表而使评分更为精确。 结论:改良的Sauvegrain法简单、可靠而且可重复性高,它补充了Greulich和Pyle图谱的不足。在临床实践中,骨骼成熟度可以通过骨龄、年生长率以及第二性征而得以很准确的评估。因此,当青春期需要进行骨骺或脊柱关节融合术时,这种方法对于确定手术时间具有重要意义。 可信水平:诊断性研究,Ⅱ级,进一步可信度参见作者介绍。  相似文献   
3.
Policosanol is a new cholesterol-lowering drug isolated and purified from sugar-cane wax. which prevents the development of lipofundin-induced lesions and foam-cell formation in New Zealand rabbits and Wistar rats. This study was conducted to examine the effects of policosanol on foam-cell formation in carrageenan-induced granulomas in rats. Eighteen Wistar rats were randomly distributed in three experimental groups which received orally for 20 days Tween 20 H2O as vehicle (control group) or policosanol at 2.5 or 25 mg kg?1. At the 11th day. lipofundin was injected intrapcritoneally for 8 days to induce formation of foam cells in the granuloma. At day 13, carrageenan was injected subcutaneously for granuloma induction and seven days later animals were killed. A significant reduction of the foam-cell formation in granulomas of policosanol-treated rats was observed. It is concluded that policosanol prevents the development of foam cells in carrageenan-induced granulomas (extravascular medium) in rats.  相似文献   
4.
In the present study we evaluated the effect of passive transfer of a mouse monoclonal (CAM) or a human polyclonal anti-cardiolipin IgG on pregnancy outcome in BALB/c mice. The mice were immunized through the tail vein immediately after mating with 10 μg of monoclonal or polyclonal anti-cardiolipin antibodies. Two other groups of mice were given a mouse irrelevant monoclonal antibody or normal human polyclonal IgG respectively, at the same dose. In mice immunized with monoclonal or polyclonal anti-cardiolipin antibody we observed a significant increase in the number of fetal resorptions and a significant reduction of the mean weights of the embryos and the placentas. In mice immunized with CAM we also found a significant decrease in the number of healthy pups, while mice infused with human aCL antibody expressed a significant reduction in the fecundity rate. The histological examination showed widespread thrombosis and necrosis in the placentas derived from the mice immunized with the anti-cardiolipin antibodies. The model supports a possible direct pathogenetic effect of anti-phospholipid antibodies in recurrent fetal loss and points out that thrombotic events at placental level can be instrumental in the pathogenesis of the obstetric complications.  相似文献   
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The aim of this study was to evaluate the possible prognostic relevance of thymidine kinase serum levels (s-TK), an indirect marker of proliferative activity, in myelodysplastic syndromes (MDS). S-TK levels were monitored by means of a radioenzyme assay in 90 patients affected by MDS (22 refractory anaemia, RA; 17 RA with ring sideroblasts, RARS; 21 RA with blast excess, RAEB; 15 RAEB in transformation, RAEB-T; 15 chronic myelomono-cytic leukaemia, CMMoL). Mean s-TK levels (U//tl) measured at diagnosis were 11–9 –12–6 for RA, 11–4–13'6 for RARS, 19–9 – 28–4 for RAEB, 39–6 – 34–3 for RAEB-T and 77–7 – 69–7 for CMMoL (normal values <5U//LI1). With the only exception of a weak relationship with lactate dehydrogenase, no correlation was found between initial s-TK values and other clinical or laboratory parameters, such as age, haemoglobin, white blood cell or platelet count, percentage of bone marrow blasts. MDS patients with s-TK >38 V/fA , a cut-off level selected by means of ROC statistical analysis, showed a significantly shorter survival than those with s-TK <38U//xl (8–2 v 37–4 months, respectively; P < 0–0001). In particular, transformation in acute myeloid leukaemia (AML) occurred in 17/21 (81%) of patients with s-TK >38U//d and 9/69 (13%) of those with lower levels at diagnosis (P < 00001), independently of FAB subtype. High s-TK levels were also useful to predict evolution in AML during the course of the disease in patients with normal initial values. Multivariate analysis confirmed the independent prognostic value of s-TK on both overall survival and risk of acute transformation. We conclude that s-TK may be an important prognostic factor in MDS, strongly correlated with development of AML.  相似文献   
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Aim This meta‐analysis provides a systematic review of studies into intellectual and attentional functioning of paediatric brain tumour survivors (PBTS) as assessed by two widely used measures: the Wechsler Intelligence Scale for Children (3rd edition; WISC‐III) and the Conners’ Continuous Performance Test (CPT). Method Studies were located that reported on performance of PBTS (age range 6–16y). Meta‐analytic effect sizes were calculated for Full‐scale IQ, Performance IQ, and Verbal IQ as measured by the WISC‐III, and mean hit reaction time, errors of omission, and errors of commission as measured by the CPT. Exploratory analyses investigated the possible impacts of treatment mode, tumour location, age at diagnosis, and time since diagnosis on intelligence. Results Twenty‐nine studies were included: 22 reported on the WISC‐III in 710 PBTS and seven on CPT results in 372 PBTS. PBTS performed below average (ps<0.001) on Full‐scale IQ (Cohen’s d=?0.79), Performance IQ (d=?0.90), and Verbal IQ (d=?0.54). PBTS committed more errors of omission than the norm (d=0.82, p<0.001); no differences were found for mean hit reaction time and errors of commission. Cranial radiotherapy, chemotherapy, and longer time since diagnosis were associated with lower WISC‐III scores (ps<0.05). Interpretation PBTS have seriously impaired intellectual functioning and attentiveness. Being treated with cranial radiotherapy and/or chemotherapy as well as longer time since diagnosis leads to worse intellectual functioning.  相似文献   
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