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991.
An automated measurement of total and free hydroxyproline in serum or urine is presented that uses flow injection analysis. After exclusion of nonspecific substances, hydroxyproline was oxidized by chloramine- T and L-cysteine with Ehrlich's reagent. The linearity obtained was from 3.8μmole/ L to 1.22 mmole/L with good precision (CV <3%). Comparison of the proposed method with HPLC yielded r = 0.939 as the correlation coefficient. Reference intervals of free and total hydroxyproline are 1.4–9.7 μmole/L, 3.8–27.2 μmole/L for serum, and 10.0–72.5 μmole/L, 25.2–303.6 μmole/L for urine, respectively. Serum free and total hydroxyproline levels in renal osteodystrophy patients on maintenance hemodialysis (N = 71) were significantly higher than in controls (P<0.0001). This method is superior to the use of HPLC with regard to stability of the color reaction. The measurement of serum free and total hydroxyproline is a useful marker for therapeutic observation of renal osteodystrophy patients. © 1994 Wiley-Liss, Inc.  相似文献   
992.
A cross-sectional radiographic screening was performed on bite-wing pairs (BW) from 1872 10-12 year old schoolchildren in the Greater Worcester, Massachusetts area to assess the prevalence of juvenile periodontitis (JP). The 3-stage screening process entailed: (1) visual identification of possible cases based upon a visual assessment of BW for interproximal crestal bone levels greater than or equal to 2 mm from the cemento-enamel junction (CEJ) on greater than or equal to 1 permanent first molar; (2) identification of probable cases based upon BW from possible cases measured with a transparent ruler calibrated in millimeters; (3) finally, clinical confirmation of JP in consenting probable cases. A total of 1038 subjects were eligible to be included in the study (greater than or equal to 3 mesial sites readable). Of the 1038 eligible subjects, 117 possible and 103 probable cases were identified in stage 1 and stage 2, respectively. A total of 99 probable cases could be contacted and 43 were examined clinically. Two cases of JP were confirmed clinically in stage 3, yielding a prevalence rate of 4.6/1000. Specifically, this report defines a rate of JP in 10-12 year-old schoolchildren for the first time. In addition, these results indicate that BW can be used to identify children with JP from large data sets. However, further studies including complete clinical and radiographic examinations are necessary to determine whether this method is adequate for large epidemiologic studies.  相似文献   
993.
Immune L3T4+ and Lyt-2+ lymphocytes play an important role in the acquired resistance of mice to challenge with virulent Candida albicans, and release macrophage-activating cytokines in response to yeast cells in vitro. To determine whether antigen (Ag)-specific cytotoxic T lymphocytes are generated during fungal infection, purified L3T4+ and Lyt-2+ lymphocytes from immunized mice were cultured in the presence of syngeneic accessory cells, Candida Ag, and IL-2. Yeast-infected bone marrow macrophages and peritoneal exudate neutrophils were used as target cells in a standard 51Cr release assay. Ag-specific, MHC-unrestricted lysis of infected macrophages was evident with immune Lyt-2+ cells after 5–10 days in culture. Under the same experimental conditions, the cytotoxic activity of L3T4+ cells was negligible, but its expression could be induced by the addition of anti-CD3 antibody.Culturing immune Lyt-2+ cells for shorter periods of time (1–2 days) resulted in preferential lysis of infected neutrophils. In addition, at limiting effector cell numbers, Ag-specific MHC-restricted lymphocytes with cytotoxic activity to infected macrophages could be identified. We suggest that C. albicans infection stimulates multiple cytotoxic T-cell precursors with varying recognition stringency, wich may have an important role in antifungal resistance in vivo.  相似文献   
994.
经调查河南省七县1988~04~1989~03孕产妇死亡率为136.1/10万,高于全国平均水平(94.7/10万)。从七县中选择了死亡率偏高的三个县(147.9/10万)为样本.进行厂降低农村孕产妇死亡率保健措施的研究。自1990年4月1日~1992年3月31日。在三县采取了以下保健措施:①加强基层妇幼卫生建设,特别是中心乡卫生院的建设,②整顿和完善三级保健网;③建全孕产妇系统管理制度,高危妊娠筛查,转化和转诊制度,④配备必要设备,建立联合小产院,实行定点接生。两年内孕产妇死亡率,由1989年的147.9/10万下降到67.7/10万,下降幅度为54.44%,最高达72.1%。此工作为实现2000年孕产妇死亡率下降一半的规划目标提供了依据。  相似文献   
995.
程乐 《实用医技杂志》2003,10(4):397-398
介入治疗是融合了内科药物治疗、外科手术治疗及医学影像学的一种特殊的治疗体系 ,其疗效受到世人瞩目并成为目前发展最为迅速的学科之一。但是 ,再好的方法也会存在不足之处 ,介入治疗也不例外。随着介入治疗在各家医院的普遍应用 ,并发症的发生也会越来越多 ,迫使人们关注这个问题。所谓介入治疗并发症 ,是指因血管造影及 (或 )血管内治疗所引起、需要一定治疗、使病人的治疗复杂化或延长病人住院时间的不良反应 ,就其全身多系统而言 ,介入治疗引发并发症的原因大致可归纳为两个主要因素即介入器材操作和引入人体内的物质(包括介入治疗所…  相似文献   
996.
桡骨头切除对肘关节稳定性影响的生物力学研究   总被引:25,自引:6,他引:19  
目的:探讨桡骨头粉碎性骨折不同治疗方法对肘关节稳定性的影响。方法:将10个尸体标本,分别测定在其它组织无损伤时,肘内侧副韧带切断时,肘内侧副韧带和前臂骨间膜均切断时的力-位移曲线(纵向位移)及肘外翻角。结果:肘内侧副韧带切断时的纵向位移及肘外翻角均大于其它组织无损伤时;肘内侧副韧带和前臂骨间膜均切断时的纵向位移及肘外翻角均大于其它组织无损伤时和肘内侧副韧带切断时,两两间比较均有显著性差异(P<0.001)。结论:在其它组织无损伤时,单纯桡骨头切除是安全的;合并肘内侧副韧带损伤时,可在有效修补韧带的同时作单纯头切除,必要时行假体置换;合并肘内侧副韧带和前臂骨间膜均损伤时,最好作假体置换。  相似文献   
997.
Studies using magnetic resonance spectroscopy in human volunteers to evaluate their livers in vivo and to analyze their blood in vitro suggest that there are measurable amounts of silicon compounds in the blood of some women with implants and that there is migration of silicone to other organs such as the liver.  相似文献   
998.
AIM: An evolutionary concept analysis was undertaken to clarify the concept of self-management of type 1 diabetes in children and adolescents. BACKGROUND: Several problems exist in the literature on self-management of type 1 diabetes in children and adolescents. There is no uniform terminology and there is no uniform definition of the concept. Also, there is no differentiation in the literature between self-management of diabetes in children and adults. METHODS: Ninety-nine references were reviewed and analysed in the disciplines of nursing, medicine, and psychology. After separate analyses revealed no significant differences across disciplines, the analyses were combined to describe the attributes, antecedents, consequences, and surrogate and related concepts. RESULTS: The three essential attributes of the concept were identified as process, activities, and goals. Self-management of type 1 diabetes in children and adolescents is an active and proactive process; it is daily, lifelong, and flexible, and it involves shifting and shared responsibility for diabetes care tasks and decision-making between child and parent. It is a process that involves collaboration with health care providers. Self-management of type 1 diabetes in children and adolescents also consists of varied and many activities related to giving insulin, monitoring metabolic control, regulating diet and exercise, to name just a few. The concept also involves goals, which may differ from one parent/child dyad to another. A working definition of the concept is suggested. CONCLUSIONS: It is hoped that a more uniform definition of the concept will enable researchers to continue investigating antecedents and consequences of the concept in a way that allows for aggregating results.  相似文献   
999.
为探讨免疫性血小板减少性紫癜(ITP)中医辨证分型与免疫机理的关系,将ITP患者中医辨证分型结合血小板相关抗体(PAIg)及T淋巴细胞亚群进行分析。发现作为本病主要抗体的PAIgG脾肾阴亏型明显高于脾虚失统型(P<0.01);OKT8+值亦显著高于脾虚失统型(P<0.05),OKT4+/OKT8+比值则明显低于脾虚失统型(P<0.05)。提示脾肾阴亏型的免疫损伤程度较脾虚失统型严重。  相似文献   
1000.
Measurement of K+ and Na+ concentrations in samples of individual brain nuclei and in ganglia of the autonomic nervous system from rabbits subjected to severe emotional stress (ES) through aperiodic stimulation of ventromedial hypothalamic nuclei and electrocutaneous stimulation revealed significantly altered levels of these ions in locus ceruleus samples from animals predisposed to ES-induced cardiovascular disorders and in samples of neurons of the caudal part of the brainstem from those resistant to such disorders. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, No 8, pp. 129–131, August, 1994 Presented by K. V. Sudakov, Member of the Russian Academy of Medical Sciences  相似文献   
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