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31.
John S. Baer Daniel R. Kivlahan G. Alan Marlatt 《Alcoholism, clinical and experimental research》1995,19(1):54-58
Alcohol use and related problems were studied from the senior year in high school to the first autumn in college for 366 heavy drinking students. Four risk factors-subject sex, family history of drinking problems, prior conduct problems, and type of college residence-were evaluated as predictors of: (1) differential changes in drinking rates, (2) differential changes in alcohol-related problems, and (3) alcohol dependence symptoms during the first college term. Results suggest that both dispositional and environmental factors are associated with changes in drinking rates and the existence of dependence symptoms. Increases in the frequency of drinking were specifically and strongly associated with residence in a fraternity (men) or sorority (women). Three risk factors were associated with increased quantity of drinking: male gender, residence in a fraternity or sorority, and a history of conduct problems. Prior conduct problems were also consistently associated with dependence symptoms during the first term in college. A family history of alcohol problems was not consistently related to changes in use rates or problems, although some analyses suggest interactive effects. Early interventions on college campuses should target individuals using additive risk profiles. 相似文献
32.
喉癌患者血小板聚集功能的测定 总被引:2,自引:0,他引:2
目的 探讨喉癌与血小板聚集功能的关系。方法 采用比浊法,对50例喉癌患进行血小板聚集功能的检测并以良性肿瘤病人、喉慢性炎性疾病病人及正常人作为对照,应用SAS计算机系统进行分析。结果 与其他组病人相比,喉癌组血小板聚集功能增强并且随着临床分期的增高有增强趋势。结论 喉癌病人的血小板聚集功能有一定的增强;测定血小板聚集功能对恶性肿瘤的疗效判定、预后评估及预测转移有一定的意义;血小板抑制剂有望成为治疗肿瘤的新方法。 相似文献
33.
小剂量阿司匹林对缺血性脑血管病患者血小板聚集功能的影响 总被引:1,自引:0,他引:1
目的 :观察小剂量阿司匹林 (ASA)对ICVD患者血小板聚集功能的影响。方法 :用花生四烯酸 (AA ,5 0 0 μmol·L-1)、二磷酸腺苷 (ADP ,5 μmol·L-1)、肾上腺素 (EPN ,5 μmol·L-1)和胶原 (COL ,2 μg·mL-1)做诱导剂检测ICVD患者服用不同剂量ASA组 ( 2 5、5 0和10 0mg·d-1)的血小板聚集率。结果 :各ASA组对AA、COL诱导聚集的变异系数较大。对AA诱导聚集无显著抑制者的比例分别为2 5mg·d-1组 44 4%、5 0mg·d-1组 2 9 6%、10 0mg·d-1组 2 9% ,其中 5 0mg·d-1组中合并糖尿病的例数较显著抑制者中多。结论 :ICVD患者中小剂量ASA作用个体差异较大 ,部分与自身危险因素有关。提示临床中ASA的效果需要实验室检测并应个体化 相似文献
34.
一个进行性肌营养不良症家系的研究 总被引:1,自引:0,他引:1
目的寻找由DNA损伤(如突变)引起的人类表型缺陷,为人类遗传资源的收集与保藏以及人类基因结构与功能的研究打下基础。方法通过实地调查得到表型缺陷家系,然后进行系谱分析。结果得到一进行性肌营养不良家系,4代41位成员中有12例患者。结论进行性肌营养不良是由DNA损伤引起的人类表型缺陷;该病症符合常染色体显性遗传;该病的发生具有一定的外显率和表现度。 相似文献
35.
Gazzaniga P. P. Ferroni P. Mina C. Pulcinelli F. M. Rizzo P. A. 《The Italian Journal of Neurological Sciences》1987,8(6):561-566
148 patients with various forms of cerebrovascular disease (CVD) were studied by means of a multiparametric analysis ofin vitro platelet aggregation, based on the following six parameters: ADP and epinephrine primary and secondary aggregation thresholds
and percent maximum aggregation induced by optimal concentrations of ADP and epinephrine. These patients were assigned to
four study groups, according to clinical diagnosis supported by CT scan, of transient ischemic attack and reversible neurological
deficit (TIA-RIND), or completed stroke, in the presence or absence respectively of antiplatelet medical treatment at the
time of the study. A statistically significant increase of thein vitro platelet aggregation was found in 44.4% of the untreated TIA-RIND patients and in 33.9% of the untreated stroke patients.
However this last group showed a higher percentage of very marked hyperaggregation. Differences between the two treated study
groups and controls were not signicant. No difference was found in collagen-and ristocetin-induced aggregation between the
patient groups and the controls.
Sommario 148 pazienti con varie forme di malattia cerebrovascolare, sono stati studiati con analisi multiparametriche dell'aggregazione piastrinica in vitro sulla base dei seguenti sei parametri: le soglie di aggregazione primaria e secondaria e l'aggregazione massima percentuale indotta da ADP ed Epinefrina. Questi pazienti sono stati suddivisi in 4 gruppi di studio in accordo con la diagnosi clinica confortata dai dati della TAC e cioè: TIA, RIND, o rammollimento in presenza o in assenza rispettivamente di un trattamento antiaggregante nel momento dello studio. è stato trovato un aumento statisticamente significativo dell'aggregazione in vitro delle piastrine nel 44.4% dei casi TIA, RIND non trattati e nel 33,9% dei casi di rammollimento non trattati. Quest'ultimo gruppo, però, ha dimostrato una più alta percentuale di iperaggregazione molto marcata. Le differenze tra i 2 gruppi di studio trattati con antiaggreganti e i controlli non erano significative. Inoltre nessuna differenza è stata riscontrata tra i gruppi e i controlli nell'aggregazione indotta da collageno e ristocetina.相似文献
36.
R. El Galta C. M. Van Duijn J. C. Van Houwelingen J. J. Houwing-Duistermaat 《Annals of human genetics》2005,69(4):373-381
In genetic epidemiological studies informative families are often oversampled to increase the power of a study. For a proband‐family design, where relatives of probands are sampled, we derive the score statistic to test for clustering of binary and quantitative traits within families due to genetic factors. The derived score statistic is robust to ascertainment scheme. We considered correlation due to unspecified genetic effects and/or due to sharing alleles identical by descent (IBD) at observed marker locations in a candidate region. A simulation study was carried out to study the distribution of the statistic under the null hypothesis in small data‐sets. To illustrate the score statistic, data from 33 families with type 2 diabetes mellitus (DM2) were analyzed. In addition to the binary outcome DM2 we also analyzed the quantitative outcome, body mass index (BMI). For both traits familial aggregation was highly significant. For DM2, also including IBD sharing at marker D3S3681 as a cause of correlation gave an even more significant result, which suggests the presence of a trait gene linked to this marker. We conclude that for the proband‐family design the score statistic is a powerful and robust tool for detecting clustering of outcomes. 相似文献
37.
Von Willebrand factor, platelets and endothelial cell interactions 总被引:13,自引:0,他引:13
Z. M. Ruggeri 《Journal of thrombosis and haemostasis》2003,1(7):1335-1342
Summary. The adhesive protein von Willebrand factor (VWF) contributes to platelet function by mediating the initiation and progression of thrombus formation at sites of vascular injury. In recent years there has been considerable progress in explaining the biological properties of VWF, including the structural and functional characteristics of specific domains. The mechanism of interaction between the VWF A1 domain and glycoprotein Ibα has been elucidated in detail, bringing us closer to understanding how this adhesive bond can oppose the fluid dynamic effects of rapidly flowing blood contributing to platelet adhesion and activation. Moreover, novel findings have been obtained on the link between regulation of VWF multimer size and microvascular thrombosis. This progress in basic research has provided critical information to define with greater precision the role of VWF in vascular biology and pathology, including its possible involvement in the onset of atherosclerosis and its acute thrombotic complications. 相似文献
38.
载脂蛋白E基因多态性与脑梗死的相关性分析 总被引:12,自引:0,他引:12
目的 探讨载脂蛋白 E基因多态性与脑梗死的关系。方法 通过聚合酶链反应 -限制性片段长度多态性 (PCR- RFL P)分析结合 DNA直接银染技术检测 6 6例脑梗死 (CI)患者的载脂蛋白 E(Apo E)基因型 (其中家系中有明确脑梗死先证者的家族聚集性脑梗死 (FMACI)亚组 2 6例 ,家系中无脑卒中史的非家族聚集性脑梗死 (NF-MACI)亚组 4 0例 ) ,并与 90例健康对照组比较 ,同时检测血脂、脂蛋白 (a) [L P(a) ]及部分载脂蛋白。结果 脑梗死组ε3/4基因型频率明显高于对照组 (P<0 .0 1) ,ε3/3基因型频率明显低于对照组 (P<0 .0 1) ;两脑梗死亚组之间的ε3/4/ε3/3基因型频率虽有上升 /下降趋势 ,但未发现明显的统计学差异 ;FMACI组高密度脂蛋白 (HDL )水平明显低于 NFMACI组 (P<0 .0 5 )。结论 Apo E基因多态性与脑梗死的发生有关 ,ε4等位基因是脑梗死的易感因子 ,ε3等位基因对脑梗死的发生有保护作用 ;Apo E基因多态性和 HDL水平双重作用于家族聚集性脑梗死的发生。 相似文献
39.
安徽省农村居民哮喘病现况调查 总被引:3,自引:1,他引:2
本文通过对安徽省农村居民哮喘病的现况调查发现,哮喘病患病率为1.33%,男性为1.48%,女性为1.19%;成人患病率为1.34%,儿童为1.32%。儿童哮喘患病率随年龄增长而下降,而成人哮喘病患病率随年龄增长而增加;儿童大部分婴幼儿起病,各年龄组中男性起病较女性晚,成人女性50%起病20岁前,而男性50%起病30岁前。农村哮喘以感染型为主,发病以冬季多见,发作主要诱因是感冒,哮喘病具有明显家族聚集性。 相似文献
40.
Martin Haupt Alexander Kurz Stefan Pollmann Barbara Romero 《Journal of neurology》1992,239(5):248-250
Summary Ninety outpatients with Alzheimer's disease according to ICD-10 diagnostic draft criteria were studied to test the hypothesis that cases with a familial aggregation are different from cases without such an aggregation with respect to cognitive impairment. In all cases the diagnosis of Alzheimer's disease was confirmed by prospective observation within 12 months of initial evaluation. Patients were divided into two groups: one consisting of 23 patients with a familial aggregation, the other consisting of 67 patients without secondary cases among first-degree relatives. By means oft-tests differences in impairment of cognitive functions between the groups were calculated. The results did not yield statistically significant differences between the groups for any of the neuropsychologically investigated cognitive deficits. Thus the hypothesis that the presence of a familial aggregation may lead to a distinct phenotype in Alzheimer's disease was not confirmed. 相似文献