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101.
An interactive CD-ROM program designed to reduce adolescent substance use was developed and evaluated. The program uses video vignettes to teach refusal skills and socially acceptable responses to substance use situations, specifically offers of marijuana. In a randomized pretest-to-posttest experiment with 74 public school students from six classes in three high schools, significant changes were observed at posttest on (1) the adolescent's personal efficacy to refuse the offer of marijuana, (2) the adolescent's intention to refuse marijuana if offered, and (3) the adolescent's perceptions of the social norms associated with substance use and the importance of respecting another's decision to refuse a drug offer. In addition, adolescents in the treatment condition were able to recall approximately 50% of the portrayed refusal strategies. Findings are discussed with regard to the potential benefits of an interactive multimedia approach for conducting substance use interventions.  相似文献   
102.
103.
目的:脑康复冲剂临床用于治疗脑血栓血瘀证患者,本实验观察其对在大鼠实验性软脑膜微循环障碍的影响。方法:大鼠预防性给药,用高分子右旋糖酐水溶液静脉注射形成大鼠软脑膜的微循环障碍,观察脑康复冲剂对大鼠微循环的影响。结果:用高分子右旋糖酐造模后,大鼠软脑膜的微循环发生障碍,表现为血液流速减慢、血细胞聚集等,脑康复冲剂组血流速度开始减慢的时间明显比生理盐水对照组延长,且分级数也明显优于生理盐水组,对高分子右旋糖酐造成的血液流态障碍,脑康复组明显好于生理盐水组(P<0.05),毛细血管网交叉点数开始减少的时间也比生理盐水对照组延长,差异显著(P<0.01)。结论:脑康复冲剂使大鼠血流速度和血液流态得到改善,具有预防和改善动物脑微循环障碍的作用。  相似文献   
104.
Summary The pharmacokinetics of high-dose metoclopramide (10 mg/kg body wt. in five infusions of 2 mg/kg body wt. each) was studied in 11 patients (5 females, 6 males) in two groups: group A with and group B (consisting of five patients) without forced diuresis. When the drug was infused, forced diuresis had no influence on the pharmacokinetics of metoclopramide (serum level after the 1st infusion was 851±361 ng/ml in group A versus 840±348 ng/ml in group B; after the 5th infusion it was 2,005±588 ng/ml in group A versus 2,463±1,350 ng/ml in group B). There were significant differences in the 24-h serum levels (582±308 ng/ml in group A versus 379±170 ng/ml in group B;P<0.05) and in the elimination half life (8.5±2.6 h in group A versus 6.1±1.1 h in group B;P<0.05). The results demonstrate that the dosage regimen originally suggested by Gralla for cytostatic drugs, with forced diuresis for high-dose metoclopramide therapy, may also be applied, with no dosage reduction, with to other cytostatic drugs which do not require forced diuresis.  相似文献   
105.
本文对三级急进高原人群资料回顾分析了急进高海拔区(>4500M)人群脑皿流量测定的临床意义。结果表明急进高原人群脑血流量较在低海拔区明显增高,有显著性差异;而急进高原人群中的急性高原反应和急性高原病患者脑血流量又显著高于高原适应人群。采用药物和吸氧治疗急进高原人群中急性高原反应人群,脑血流量明显降低,急进高原人群的高原反应程度和急性高原病的发病率亦相应降低。因此监测急进高原人群的脑血流量,不仅可以早期发现急性高原反应及急性高原病患者,更可以预测急性高原易感者,可为急性高原病的早期治疗和预防,扩大高原适应人群提供重要的理论依据。  相似文献   
106.
High altitude pulmonary edema (HAPE) is a potentially fatal complication in response to exposure to low O2 at high altitudes. Hypoxia, by causing pulmonary vasoconstriction, increases pulmonary vascular resistance and pulmonary arterial pressure, both of which are features in the pathogenesis of HAPE. Uneven hypoxic pulmonary vasoconstriction is thought to be responsible for increased capillary pressure and leakage, resulting in edema. O2-sensitive ion channels are known to play pivotal roles in determining vascular tone in response to hypoxia. K+, Ca2+ and Na+ channels are ubiquitously expressed in both endothelial and smooth muscle cells of the pulmonary microvasculature, subfamilies of which are regulated by local changes in PO2. Hypoxia reduces activity of voltage-gated K+ channels and down-regulates their expression leading to membrane depolarization, Ca2+ influx in pulmonary artery smooth muscle cells (by activating voltage-dependent Ca2+ channels) and vasoconstriction. Hypoxia up-regulates transient receptor potential channels (TRPC) leading to enhanced Ca2+ entry through receptor- and store-operated Ca2+ channels. Altered enrichment of ion channels in membrane microdomains, in particular in caveolae, may play a role in excitation–contraction coupling and perhaps in O2-sensing in the pulmonary circulation and thereby may contribute to the development of HAPE. We review the role of ion channels, in particular those outlined above, in response to low O2 on vascular tone and pulmonary edema. Advances in the understanding of ion channels involved in the physiological response to hypoxia should lead to a greater understanding of the pathogenesis of HAPE and perhaps in the identification of new therapies.  相似文献   
107.
内蒙古中学生神经衰弱患病情况调查   总被引:1,自引:0,他引:1  
目的 :调查研究内蒙古不同民族中学生神经衰弱患病情况。方法 :采用随机整群抽样法 ,对内蒙古八所中学六个民族的中学生进行调查 ,以CCMD -2 -R中神经衰弱标准作最后医学诊断 ,所得数据进行卡方检验。结果 :总患病率为 2 3 5 % ,城市学生患病率高于乡村学生 ,高中生患病率高于初中生 ,均有显著差异 (P <0 0 5 ) ;男女生之间患病率无显著性差异。回族学生患病率最低 ,鄂伦春族学生患病率最高 ,汉族与回族学生之间患病率无显著差异 ,而与蒙古族、鄂温克族、鄂伦春族、达斡尔族之间患病率有显著差异(P <0 0 5 )。结论 :内蒙古中学生神经衰弱患病率较高 ,对来自于城市生、高中生应作为重点防治对象 ,关注少数民族学生的心理健康状况  相似文献   
108.
Fifteen patients were studied who had unusual reactions following insect stings. These included serum sickness, neurologic disease, renal disease, and delayed hypersensitivity-type reactions. The clinical features are briefly outlined. Measurements were made of serum venom-specific IgE and IgG antibodies. These antibodies were present in some patients and in these instances suggested an immunologic pathogenesis for the reactions. Alternative etiologies for the unusual reactions are also discussed.  相似文献   
109.
A survey of 58 gingival biopsies revealed the presence of periodontal high endothelial-like venules (PHELVs) in chronically inflamed gingival tissues. PHELVs were found to exchange polymorphonuclear cells (PMNs) almost exclusively in advanced periodontitis, with PMNs greatly exceeding the number of mononuclear cells found in PHELVs (P less than 0.001). Electron microscopy confirmed the emigration of PMNs from these vessels. The enzyme histochemical and ultrastructural features as well as the 35SO4 uptake properties of PHELVs were similar to those of the well-characterized high endothelial venules (HEVs) of rat lymph nodes. It is generally accepted that HEVs in lymphoid tissues and inflammatory sites are specially adapted to assist in the emigration of lymphocytes. However, the observation of preferential PMN emigration in the apparent absence of lymphocyte exchange from PHELVs compels further investigation of other possible functions for HEVs. In relation to this, endothelial cells are capable of producing potent cytokines and inflammatory mediators which may contribute to the development of lesions, and the possibility is discussed that high endothelial cells are functionally adapted to enhance the production of such factors.  相似文献   
110.
目的为了探讨中学教师的心理幸福感状况。方法采用Ryff《心理幸福感量表》,对石家庄市4所中学的教师进行调查。结果性别在心理幸福感各纬度上的差异不显著;不同性质学校的教师在自主性上有显著的差异;不同工龄的教师在个人成长方面有显著的差异;不同职称的教师在个人成长和自我接纳上有显著差异;不同婚姻状况的教师在个人成长和与他人积极关系上有非常显著的差异。结论中学教师的心理幸福感在性别上没有差异,在不同性质学校、不同工龄、不同职称和不同婚姻状况上有显著的差异。  相似文献   
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