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11.
Nephrotoxic cysteine conjugates derived from a variety of halogenated alkenes are enzymatically activated via the beta-lyase pathway to yield reactive sulfur-containing metabolites which bind covalently to cellular macromolecules. Mitochondria contain beta-lyase enzymes and are primary targets for binding and toxicity. Previously, mitochondrial protein and/or DNA have been considered as molecular targets for cysteine conjugate metabolite binding. We now report that metabolites of nephrotoxic cysteine conjugates form covalent adducts with rat kidney mitochondrial phospholipids. Rat kidney mitochondria were incubated with the 35S-labeled conjugates S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (TFEC), S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine (CTFC), S-(1,2-dichlorovinyl)-L-cysteine, and S-(1,2,3,4,4-pentachlorobutadienyl)-L-cysteine. Quantitation of metabolite binding to whole mitochondria and to mitochondrial protein and lipid fractions revealed that as much as 42% of the 35S-label associated with the mitochondria was found in the lipid fraction. Total lipids were also extracted from 35S-treated mitochondria and separated by thin-layer chromatography. 35S-Containing metabolites were found in the lipid fractions from mitochondria treated with each of the conjugates. Lipids from both [35S]CTFC- and [35S]-TFEC-treated mitochondria contained major 35S-labeled lipid adducts which had similar mobility by thin-layer chromatography. Fatty acid analysis, 19F and 31P NMR spectroscopy, and mass spectrometric analyses confirmed that the major TFEC and CTFC adducts are thioamides of phosphatidylethanolamine.  相似文献   
12.
Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight.  相似文献   
13.
14.
OBJECTIVE: To understand the role of nasal mucous epithelial cells to hypoxia in early stage of nasal polyps(NP) formation. METHODS: Epithelial cells of NP and inferior turbinate (IT) were cultured without serum under normal oxygen and hypoxia, and stimulus of inflammatory cytokines. Erythropoietin (EPO) was regarded as hypoxia mark, and expression of vascular endothelial growth factor(VEGF) mRNA and protein derived from epithelial cells were detected respectively by in situ hybridization and ELISA. RESULTS: 1. Under hypoxia, EPO mRNA was expressed intensely in epithelial cells from NP and IT, and there was no significant difference between both of them. This result suggested that EPO might be regarded as a hypoxic mark. 2. The ability of producing VEGF mRNA increased with cytokines stimulation, especially under hypoxia. Protein level of VEGF from epithelial cells of NP and IT increased with cytokines stimulation, especially in hypoxia and was time-dependent. CONCLUSION: Epithelial cells actively produce vast VEGF under hypoxia. The VEGF induced by hypoxia of the mucosa in middle meatus is of importance in the formation of nasal polyps(NP) in early stage, which may be the major cause of NP formation in middle meatus.  相似文献   
15.
本文报道了气管切开术各种并发症的发病率,并对术中或术后并发症的病的病因、发病机理、治疗和预防进行了讨论。  相似文献   
16.
Oxidative stress is an important factor in many pathological conditions such as inflammation, cancer, ageing and organ response to ischemia-reperfusion. Humans have developed a complex antioxidant system to eliminate or attenuate oxidative stress. Liver ischemia-reperfusion injury occurs in a number of clinical settings, including liver surgery, transplantation, and hemorrhagic shock with subsequent fluid resuscitation, leading to significant morbidity and mortality. It is characterized by significant oxidative stress but accompanied with depletion of endogenous antioxidants. This review has 2 aims: firstly, to highlight the clinical significance of liver ischemia-reperfusion injury, the underlying mechanisms and the main pathways by which the antioxidants function, and secondly, to describe the new developments that are ongoing in antioxidant therapy and to present the experimental and clinical evidence about the role of antioxidants in modulating hepatic ischemia-reperfusion injury.  相似文献   
17.
眼针治疗阵发性室上性心动过速120例的即时疗效观察   总被引:2,自引:0,他引:2  
目的:观察眼针对阵发性室上性心动过速的即时疗效。方法:选择符合诊断标准的门诊患者120例,针其眼针穴区:心区和上焦区。针后30分钟描记心电图,计算心率,观察眼针对阵发性室上性心动过速的影响。结果:显效103例,占85.83%;有效9例,占7.5%;无效8例,占6.66%;总有效率93.33%.结论:眼针对阵发性室上性心动过速有较好的即时疗效。  相似文献   
18.
OBJECTIVES: To explore the morphological and functional findings of transvaginal sonography (TVS) in the diagnosis and management of distal ureteral calculi. METHODS: We retrospectively reviewed the imaging studies in seven cases of distal ureteral calculi (study group) and 20 cases of female volunteers without urinary tract infection (control group). All 27 patients had undergone TVS for assessment of the lower urinary tract. The variables measured on ultrasound included the presence or absence of distal ureteral calculi, the size and location of a calculus if present, the presence or absence of the ureter jet phenomenon, morphological changes of the ureteral papilla and adjoining tissue, and the height of the ureteral papilla, as well as vascular changes seen on Doppler imaging. RESULTS: In the controls, 80% of the ureteral papillae were triangular and 20% trapezoidal. The average (+/-SD) height of the ureteral papillae was 3.5 +/- 0.7 mm on the right and 3.6 +/- 0.9 mm on the left. There was no statistically significant difference between the heights of the right and left papillae (P = 0.619). In the study group, echogenic stones were identified in all seven patients and a hypoechogenic tubular structure connected to the involved papilla was identified in 6/7 patients. The average height of the involved papilla was 6.7 +/- 1.6 mm. Ureteric jets were visible in all patients in both the study and control groups. CONCLUSION: In patients with distal ureteral calculi, TVS provides a rapid, non-invasive and repeatable means of assessing the morphology and function of the distal ureter.  相似文献   
19.
100例性病患者心理健康状况调查分析   总被引:3,自引:1,他引:2  
目的:探讨性病患者的心理健康状况,为临床治疗和护理提供依据。方法:采用症状自评量表(SCL-90)对100例性病患者的心理健康状况进行测验。结果:100例性病患者SCL-90检测的阳性率为51%,阳性样本因子分居前的是敌对、强迫症状、抑郁、人际敏感。结论:性病患者广泛存在的心理问题,在药用治疗的同时应注意心理方面的治疗和疏导。  相似文献   
20.
背景: 前期研究表明广西18~22岁少数民族学生体质量偏轻。 目的:拟进一步了解广西2645名少数民族学生体型及体质健康状况,寻找影响的关联因子。 设计、时间及地点:追踪调查,于2004-12/2007-12在广西民族大学完成。 对象:广西民族大学2003/2005三次体质健康测试的全体学生2 645人。男1 337人,女1308人,年龄为18~20岁,共15个民族。 方法:根据2003年教育部、体育总局《学生体质健康标准(试行方案)》和实施方法分为形态指标、技能指标和身体素质指标3大类。对2 645名少数民族身体机能与体质量指数变化的跟踪调查。 主要观察指标:身高、体质量、肺活量、立定跳远、坐位体前屈、体质量指数。 结果:①广西民族大学2003级学生大学3年期间男生身高、体质量增长率比全国同期多2.45%,身体形态发育正处于高峰期,女生成偏瘦型体型,身体形态发育情况总体欠佳。②男女学生在刚入校时肺活量机能较差,远远低于同期全国平均水平。3年后男生肺活量增长率为11.55%、女生肺活量增长率为27.72%,分别高于全国同期肺活量增长率。③坐位体前屈机能高于同期全国平均水平,男生呈逐年上升趋势,同期全国男性呈下降趋势;同期全国乡村女生均呈逐年上升趋势。④立定跳远机能提高较大,3年后增长率为18.15%,明显高于全国同期立定跳远增长率水平的2.61%。女生立定跳远机能总体不如全国同期水平。⑤体质量指数总体与同期全国乡村男女学生体质量指数比较稍低一些(P < 0.01)。 结论:2 645名少数民族学生发育正处于高峰期;肺活量机能不及全国同期平均水平。男女体质量指数分布有所不同,体质量偏轻者女生多于男生,表明学生营养状况总体欠佳。  相似文献   
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