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31.
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A multilaboratory study was conducted to develop a system for standardizing alanine aminotransferase (ALT) acceptability criteria ("cutoffs") for donated blood. Without standardized cutoffs, each laboratory must develop its own cutoff, and this may not make optimal use of ALT testing to reduce transmission of non-A, non-B hepatitis (NANB). Defining an ALT acceptability criterion in absolute terms is necessary because relative cutoffs based on local donor populations may be affected by the prevalence of NANB in each community. This study involved 16 laboratories using 23 different analytic systems. The ALT results of the analysis of a plasma reference sample could be used to translate mathematically a single, absolute cutoff to units applicable to each analytic system. The distribution of ALT results in 1.4 million donations from across the country was established; basing the cutoff on this sample avoids the problems inherent in using a local donor base to establish a cutoff. We propose the implementation of a system to standardize ALT acceptability criteria to an activity level defined by analysis of a nationwide donor sample.  相似文献   
33.
Fracture healing is a complex process that involves several cell types; as a previous report suggested an increase in osteoblast (OB) precursors in peripheral blood during this process, this paper examines the role of circulating bone cell precursors in this process in the light of a prior suggestion that OB precursors are increased. Nine healthy men less than 60 years old with traumatic fractures were enrolled. The parameters circulating OB precursors (osteocalcin+/alkaline phosphatase+/CD15− cells) and osteoclast precursors (CD14+/CD11b+/vitronectin receptor + cells) were measured by flow cytometry; bone formation markers and TGFβ1, by ELISA; and PTH, by RIA in serum on arrival at the emergency department (baseline) and 15 days after fracture. Bone cell precursors behaved differently during healing. TGFβ1 was inversely correlated with OB number, but increased their degree of maturation at baseline. Bone formation markers and TGFβ1 were increased after fracture, whereas PTH was decreased. The TGFβ1 increase was directly correlated with age, whereas age was not correlated with the precursors. In conclusion, we confirm the role of TGFβ1 in fracture healing; and its possible role in the control of pre-OB homeostasis. There was no variation in circulating precursor cells during healing, though the increase in TGFβ1 may suggest increased pre-OB maturation and homing to the injured site.  相似文献   
34.

Background  

Mandatory vaccination has contributed to the success of immunisation programmes but voluntary vaccination allows people to be responsible for their own health. There are benefits from both policies and the arguments between them remain subject to debate within and without the scientific community, both nationally and internationally. The aim of this study is to assess the opinions of those who actually work in the Vaccination Service.  相似文献   
35.
Recent studies of animal models have suggested that an increase in the number of T cells due to both peripheral expansion and increased thymic T cell output plays a key role in the regulation of bone loss after ovariectomy. Osteoclastogenic cytokines which are either produced by T cells or activate T cells have also been implicated in ovx induced bone loss. Among them are TNF alpha and IL-7. The present study investigates the role of thymectomy (THX) and IL-7 in bone metabolism in humans. We studied T cells subsets, cytokine production and bone metabolism in 13 women thymectomized for Myasthenia gravis as compared to healthy controls. Our data demonstrate that the number of CD4+ and TNF-producing T cells is lower in THX women as compared to euthymic controls. However in THX women the residual T cells produce higher levels of IL-7 and RANKL. Furthermore, flow cytometry shows that IL-7 is produced by T and B cells. Serum levels of TNF alpha were unaffected by THX and both serum TNF alpha and the RANKL/OPG correlated inversely with BMD. There were no differences in bone turnover and bone mineral density between THX women and the controls. These data suggest that THX decreases the number of TNF-producing CD4+ T cells but does not alters serum TNF levels. The RANKL/OPG ratio and indices of bone metabolisms are also not affected by THX, although THX increases the levels of IL-7 and RANKL. Further studies are needed to clarify the role of thymus in bone metabolism and osteoclastogenesis in postmenopausal women.  相似文献   
36.
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Bone turnover in hyperthyroidism before and after thyrostatic management   总被引:2,自引:0,他引:2  
Hyperthyroidism is associated with enhanced osteoblastic and osteoclastic activity, and patients frequently have low bone mineral density and high bone turnover. The aim of this study was to examine the bone formation and resorption markers trend in 12 female patients, before and after normalization of thyroid activity. The following measurements were made at baseline and 1 and 6 months after hormone normalization induced by methimazole treatment: total alkaline phosphatase (ALP), bone alkaline phosphatase (BALP), collagen type C-terminal propeptide (PICP), osteocalcin (BGP), telopeptide (ICTP), urinary-hydroxyproline/urinary creatinine (uOHP/uCreat), urinary calcium/urinary creatinine (uCa/uCreat) and deoxypyridinoline crosslinks (D-Pyr). Compared with controls, all of these parameters were significantly increased (ALP p = 0.014; BALP p = 0.0001; PICP p = 0.013; BGP p = 0.009; ICTP p = 0.0001; uOHP/uCreat p = 0.002; uCa/uCreat p = 0.044; crosslinks p = 0.0001). After treatment the values of ALP, BALP and PICP in hyperthyroid patients showed an initial slight increase and then a significant downwards trend (ALP p = 0.008, BAP p = 0.001, PICP p = 0.026). Furthermore, resorption markers showed a significant decrease (uOHP/ uCreat p < 0.005 and D-Pyr p < 0.008). As regards lumbar BMD patients, measurements were significantly reduced in comparison with the control group (p = 0.005). Six months after serum thyroid hormones level normalization, we observed a significant increase (p=0.014 vs baseline). Both neoformation and resorption markers are useful to assess pathological bone turnover and bone involvement in hyperthyroidism. They could also be employed to monitor the effect of antithyroid treatment on bone and to indicate if bone antiresorption therapy should be considered.  相似文献   
38.
We assessed interobserver reliability of the International Headache Society (IBIS) classification for diagnosis of primary headaches. The study was performed on 103 patients consecutively seen at two Headache Centres. Each patient was given a structured interview recorded on videotape. Four experienced clinicians then reviewed the interviews separately and made a diagnosis of headache according to IHS criteria at the one- and two-digit levels. At both the one- and the two-digit level the agreement was substantial (Kappa = 0.74 and 0.65, respectively). The analysis of reliability for each of nine items necessary for diagnosis showed an agreement ranging from substantial (Kappa = 0.69) to almost perfect (Kappa = 0.89). Our results indicate that the IHS classification has a good reliability for the diagnosis of primary headaches at the one- and two-digit levels.  相似文献   
39.
研究生一年级学生运动等级与其健康状况的相关性   总被引:2,自引:0,他引:2  
目的:调查研究生一年级学生的体育锻炼和健康状况,并分析其相关性。方法:调查于2005-09/10完成。选取西南大学和重庆大学2005级研究生一年级学生作为调查对象,共发放问卷190份,男90份,女100份。进行问卷调查,当场收回问卷。问卷内容:①自测健康评定量表:由48个条目构成,1~17为自测生理健康评定子量表(170~0分),19~34为自测心理健康子量表(150~0分),35~47为自测社会健康子量表(120~0分),分数越高代表越健康。②体育活动等级量表:主要调查调查对象上1个月参加体育锻炼的运动量,运动量=强度×时间×频率,强度与频率从1~5等级分别计1~5分,时间从1~5等级分别计0~4分,故运动量最高分为100分,最低分为0分。结果:有效回收176份问卷进入结果分析。①不同性别调查对象在运动等级上的分布情况:研究生一年级男女新生的运动量水平都偏低(男生:31.80±23.19,女生:15.57±15.39),且性别对运动量有显著的主效应(P<0.01),女生在运动量上的得分显著偏低。②调查对象健康状况各维度与运动量的相关性:运动量与总体健康、生理健康、心理健康和社会健康都存在显著相关性(r=0.150~0.238,P<0.05~0.01),生理健康对运动量有显著的预测作用(P<0.05)。③不同运动量等级调查对象的健康量表得分:运动等级对生理健康有显著的主效应(P<0.01),随着运动量的增加,研究生一年级学生的生理健康水平不断提高。结论:研究生一年级学生的体育锻炼运动量与健康水平存在着明显的正相关,随着运动量的增加,生理健康、心理健康及社会健康水平均不断增加。  相似文献   
40.
目的:以病理活检结果为金标准,评估多普勒超声检查对移植肾排斥反应的诊断价值。方法:选择2003—01/2006—12在中国医科大学附属第一医院器官移植科行肾移植并在术后行超声检查的患者176例,均知情同意。①实验分组:根据术后移植肾功能分为2组,移植肾功能不良组78例,其中30例次行病理活检;移植肾功能正常组98例。②实验方法及评估:对患者移植肾行多普勒超声检查,参数选择峰收缩期流速、平均舒张期流速、阻力指数及血管显示率。血管显示率的评估标准(0~5级):0级为肾动脉及其远侧血管未显示;5级为肾各级血管均显示良好。以病理活检结果为金标准,分别选取阻力指数=0.7,0.75,0.8,0.85为诊断界值进行诊断试验。结果:169例患者进入结果分析,脱落7例。①峰收缩期流速、平均舒张期流速不呈正态分布,无法作为肾功能评价指标。30例次病理活检中共有28例次被确诊为排斥反应,急性排斥反应15例次,慢性排斥反应13例次。②肾功能正常组患者中血管显示率5级者占63.30%,4级者占36.73%。肾功能不良组患者中血管显示率4级者占41.03%,3级者占46.15%,2级者占10.30%,1级者占2.60%。③移植肾功能不良组患者阻力指数显著高于移植肾功能正常组(P〈0.01)。移植肾功能不良组患者移植肾功能恢复后阻力指数显著低于移植肾尚未恢复时(P〈0.01),其中99%以上的患者△(阻力指数)≥0.20。④界值阻力指数=0.75的诊断试验的敏感性、特异性和准确性最高,均达到100%。结论:当移植肾血管阻力指数升高至0.75以上,特别是同一患者自身对照升高超过0.2以上和或血管显示率低于4级,结合临床表现和生化结果,提示可能出现移植肾排斥反应。  相似文献   
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