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101.
2-乙氧基乙醇急性染毒大鼠血清和睾丸某些抗氧化指标的变化 总被引:1,自引:0,他引:1
目的 观察2-乙氧基乙醇(2-Ethoxythanol,EE)急性染毒对SD大鼠血清和睾丸某些抗氧化指标的变化,探讨EE致睾丸损伤的可能机制。方法 选择健康雄性SD大鼠,体重180-220g。随机分为对照组、EE800、1600和3200mg/kg组4组,每组24只。采取一次性灌胃染毒。于灌胃后12、24、48和72h,将各组动物随机处死6只,留取动物血液、睾丸,制备血清和睾丸匀浆,测定血清和睾丸匀浆脂质过氧化物(LPO)水平、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性,以及血清铜蓝蛋白(CP)活性。结果 与对照组比较,各染毒组睾/体比明显下降(P<0.05),睾丸匀浆LPO水平和血清CP活性增高。染毒12、24h,血清CAT、睾丸匀浆CAT和SOD活性增高,而染毒48、72h后,血清CAT、睾丸匀浆CAT和SOD活性显著降低(P<0.05)。EE各染毒组血清LPO水平和SOD活性变化不明显。结论 推测EE毒作用的靶器官可能是睾丸,睾丸抗氧化功能的改变是EE致睾丸毒性的可能机制。 相似文献
102.
Physical inactivity, excess adiposity and premature mortality 总被引:5,自引:0,他引:5
The purpose of this report is to review the evidence that physical inactivity and excess adiposity are related to an increased risk of all‐cause mortality, and to better identify the independent contributions of each to all‐cause mortality rates. A variance‐based method of meta‐analysis was used to summarize the relationships from available studies. The summary relative risk of all‐cause mortality for physical activity from the 55 analyses (31 studies) that included an index of adiposity as a covariate was 0.80 [95% confidence interval (CI) 0.78–0.82], whereas it was 0.82 [95% CI 0.80–0.84] for the 44 analyses (26 studies) that did not include an index of adiposity. Thus, physically active individuals have a lower risk of mortality by comparison to physically inactive peers, independent of level of adiposity. The summary relative risk of all‐cause mortality for an elevated body mass index (BMI) from the 25 analyses (13 studies) that included physical activity as a covariate was 1.23 [95% CI 1.18–1.29], and it was 1.24 [95% CI 1.21–1.28] for the 81 analyses (36 studies) that did not include physical activity as a covariate. Studies that used a measure of adiposity other than the BMI show similar relationships with mortality, and stratified analyses indicate that both physical inactivity and adiposity are important determinants of mortality risk. 相似文献
103.
目的 分析山医群体中国地鼠E家系的遗传纯度。方法 应用经过筛选的 3 1条随机引物对中国地鼠E家系 12只个体基因组DNA进行RAPD扩增 ,计算近交个体间的相似系数。结果 所有样品的相似系数0 943 1到 0 9978之间变动 ,平均相似系数为 0 9749,聚类分析得到了这些个体的同源树资料。结论 山医群体E家系有较高的遗传纯度 相似文献
104.
本文复制了慢性、应激性水浸溃疡模型,23℃每天拘束水浸4小时,4天后所得溃疡病变明显,溃疡指数是13.8士4.5mm~2,且再现性良好,是一个较好的慢性、应激性溃疡模型。哌哌西平对此溃疡具有较强的防治作用。 相似文献
105.
采用临床流行病学方法对IgG指数和IgG合成率的实用价值进行评价。结果发现:在对多发性硬化(MS)的诊断中,IgG指数的敏感性、特异性和阳性结果似然比分别是60%、65%和1.80,而IgG合成率分别为50%,65%和1.43。在排除皮质类固醇激素的影响后,IgG指数的敏感性和阳性结果似然比分别是84%和2.4,IgG合成率则分别是79%和2.26。此外,IgG指数和IgG合成率对于判断是否存在中枢神经系统器质性损害有较大的意义 相似文献
106.
J. Thiele T. K. Zirbes J. Lorenzen H. M. Kvasnicka S. Scholz A. Erdmann U. Flucke V. Diehl R. Fischer 《Annals of hematology》1997,75(1-2):33-39
In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed
cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition
to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly
(PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML).
Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal
antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index
was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed
the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and
PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid
or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the
control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant
expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant
feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the
latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive
lesions extends previous experimental data on hematopoietic cell kinetics.
Received: 10 March 1997 / Accepted: 18 May 1997 相似文献
107.
Reiner Mengel Matthias Eigenbrodt Thomas Schünemann Lavin Florès-de-Jacoby 《Journal of clinical periodontology》1996,23(5):437-443
Abstract From August to October 1991, the periodontal status of 1001 Yemenis representing the age groups 12-14, 15-19, 20-24 and 35-44 years was recorded and evaluated with preference to the CPITN, the calculus index and clinical attachment levels. The impact of chewing khat, the leaves of a cultivated, alkaloid shrub, and of using the traditional miswak chewing stick for oral hygiene purposes were investigated. The results show that 6.9% of the juvenile probands (15-19 years) had healthy periodontal tissue (CPITN 0). whereas bleeding on probing and calculus (CPITN 1+2) were registered in 86.2%. In the 35-44 year age group. 1.7% were periodontally healthy, whereas 84.5% displayed plaque retention or shallow pocketing (CPITN 2-3) and 12.5% deep pocketing (CPITN 4). The treatment needs in all age groups are confined primarily to calculus removal and instruction in oral hygiene. The clinical attachment level and the calculus index revealed age-related attachment loss and calculus formation, primarily among male probands. The higher khat consumption among the male population is reflected in its detrimental effect on the periodontal tissue, especially among younger probands. Oral hygiene aids have also an influence on periodontal status, with a toothbrush proving more efficient than the miswak. WHO efforts directed towards prophylactic programs need to be intensified but can be staffed by dental hygienists. 相似文献
108.
Objective To analyze the relations between obstructive sleep apnea and bradyarrhythmia.Methods From 1999 to 2005,203 patients who came from Bering Tongren Hospital and Fuwai Hospital were found to have sleep apnea in an ambulatory study. A Hoher electrecardiogram was recorded for 24 hours within 2 weeks after patients were diagnosed as obstructive sleep apnem Results Nocturnal episodes of bradyarrhythmia were identified in 12(5.9%)of 203 patients.Body mass index and respiratory disturbance index in patients with bradyarrhythmia(n=12)were higher than those in patientswithour bradyarrhymia(n=191)(34±5 735.24±6 and 63±15 vs.25±5,respectively,both P<0.01).There was a significant difference in end-apneic oxygen saturation in apnea/hypopnea episodes with and without bradyarrhythmia(63%±15% vs.75%±11%,P<0.05).A linear relation between end-apneic oxygen saturation and number of sinus arrests and heart blocks was not found.Conclusions Patients with apnea-associated bradyarrhythmia have higher body mflgB index and higher respiratory disturbance index than patients without bradyarrhythmi&Bradyarrhythmia occurres independently from decrease in oxygen saturation. 相似文献
109.
目的:观察缺氧及停止缺氧后对大鼠心肌血流量的影响。方法:34只Wistar大鼠,随机分为4组:①平原对照组;②急性缺氧组;③慢性缺氧组;④返回平原组。以放射性生物微球法测定心肌血流量。结果:急性缺氧引起PaO2、心输出量及氧运送量降低,但左、右心室心肌血流量明显增加;慢性缺氧时右心室收缩压、血球压积、血液粘滞性及右心室生理指数明显增加,而心肌血流量接近正常。停止缺氧30d后,上述所有指标均与平原以 相似文献
110.
目的建立重庆市正常牙合青少年牙颌模型牙列指数的正常值,为正畸临床提供依据.方法选取重庆市正常牙合青少年牙颌模型92付(男45付,女47付),测量牙冠宽度、牙弓宽度,计算Bolton指数和Pont指数,对测量结果进行统计分析并与国内外相关资料进行对比研究,对Bolton指数和Pont指数的临床应用价值进行评价.结果Bolton指数和Pont指数存在种族和地区差异,结论Bolton指数和Pont指数在正畸临床中均有一定的应用价值,临床上应参照本民族和地区的标准. 相似文献