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121.
大学生网络成瘾影响因素分析   总被引:5,自引:0,他引:5  
目的探讨大学生网络成瘾的原因。方法采用中文网络成瘾量表、自尊量表、孤独量表、大学生日常生活压力调查表、自编大学生网络使用行为调查问卷,对1450名大学生进行了调查,回收有效问卷1038份。结果对大学生网络成瘾的现状、网络使用特征及心理特征进行调查,建立大学生网络成瘾影响因素模型。结论①大学生网络成瘾呈轻度、重度两种水平,这两种水平总流行率达到14.84%;②网络使用时间、娱乐上网、交易上网、人际上网与网络成瘾存在着显著正相关关系;③自尊、孤独、大学生日常生活压力对网络成瘾有很好的预测作用;④网络成瘾是特定的个体心理特征与特定的网络使用行为、外部环境交互作用的结果。  相似文献   
122.
目的了解福州地区综合性大学本科生睡眠状况,为心理健康教育提供依据。方法用匹兹堡睡眠质量指数问卷(PSQI),对328名福州市综合性大学本科生进行调查。结果①大学生睡眠质量总分为5.51±2.28,睡眠状况不佳的有22.9%;②性别对主观睡眠质量、睡眠障碍和总体睡眠质量有影响;③不同年级大学生的睡眠情况存在显著差异;④专业因素对睡眠障碍有影响;⑤拥有电脑情况对睡眠障碍有影响。结论应重视大学生睡眠状况,有针对性地加强睡眠咨询和干预。  相似文献   
123.
The human {T:T act} AMLR was characterized in its relationship to the {T:Non-T} AMLR and its validity as a nonxenogeneic antigen induced response was extended. Human T cell lines, established from responding T cells in an autologous mixed lymphocyte reaction (MLR), were maintained in medium containing human serum and interleukin-2 (IL-2). These cells stimulated 3H-thymidine incorporation by autologous T cells and by autologous unfractionated blood mononuclear cells. Freshly activated T cells isolated from an autologous MLR stimulated autologous T cells to a lesser extent could be enhanced by adding IL-2. Twenty-five to 50% of T cells stimulated by activated T cells express the T8 determinant. In contrast, we have previously shown that less than 10% of T cells activated after 6 days in culture with non-T cells express the T8 determinant. The number of T8 bearing cells were increased significantly after 10 days in culture with non-T cells. This suggested that two types of reactions, the {T:Non-T} and {T:T act} AMLR, might occur in sequence when T cells and autologous non-T cells are cocultured: first, the activation of T4 cells by non-T cells, then by the activation of T8 cells by activated T4 cells. Finally, activated T cells can stimulate unfractionated autologous mononuclear cells without prior exposure to sheep erythrocytes or fetal calf serum.  相似文献   
124.
Variation in sister chromatid exchange (SCE) frequency in lymphocytes of 125 persons was compared using a multivariate general linear model. The study was performed to determine whether SCE frequency differs with respect to age, sex, smoking, and breast cancer status. Study subjects were divided into: members of two branches of families having an excess of cancer (primarily breast) including a brother and sister in one family who developed nonbreast malignancies within 1 yr of the study; women in both families successfully treated for breast cancer (all at least 5 yr posttreatment); and women from the general population with confirmed breast cancer.Controls consisted of spouses who married into the high-risk kindreds, hospital personnel, and others (primarily tradesmen without history of occupational exposure). Results show that: (1) Women with active breast cancer have a significantly higher mean SCE frequency than control women or women greater than 5 yr posttreatment for breast cancer; (2) Cigarette smokers show a significantly higher number of SCEs than was observed in nonsmokers; (3) The increase in SCE level in smokers is dose-related to exposure as measured by cumulative pack-years; (4) SCE values in both high-risk families are not significantly different from controls; (5) Neither the age nor sex of the individual affects SCE frequency; and (6) The observed distribution of exchanges agrees with that expected based on the proportion of the genome represented by each chromosome group.  相似文献   
125.
Excessive neutrophil influx, their released neutrophil extracellular traps (NETs), and extracellular histones are associated with disease severity in influenza-infected patients. Neutrophil chemokine receptor CXC chemokine receptor 2 (CXCR2) is a critical target for suppressing neutrophilic inflammation. Herein, temporal dynamics of neutrophil activity and NETosis were investigated to determine the optimal timing of treatment with the CXCR2 antagonist, SCH527123 (2-hydroxy-N,N-dimethyl-3-[2-([(R)-1-(5-methyl-furan-2-yl)-propyl]amino)-3,4-dioxo-cyclobut-1-enylamino]-benzamide), and its efficacy together with antiviral agent, oseltamivir, was tested in murine and piglet influenza-pneumonia models. SCH527123 plus oseltamivir markedly improved survival of mice infected with lethal influenza, and diminished lung pathology in swine-influenza–infected piglets. Mechanistically, addition of SCH527123 in the combination treatment attenuated neutrophil influx, NETosis, in both mice and piglets. Furthermore, neutrophils isolated from influenza-infected mice showed greater susceptibility to NETotic death when stimulated with a CXCR2 ligand, IL-8. In addition, CXCR2 stimulation induced nuclear translocation of neutrophil elastase, and enhanced citrullination of histones that triggers chromatin decondensation during NET formation. Studies on temporal dynamics of neutrophils and NETs during influenza thus provide important insights into the optimal timing of CXCR2 antagonist treatment for attenuating neutrophil-mediated lung pathology. These findings reveal that pharmacologic treatment with CXCR2 antagonist together with an antiviral agent could significantly ameliorate morbidity and mortality in virulent and sublethal influenza infections.

Influenza virus infections during pandemic outbreaks and yearly seasonal epidemics cause significant morbidity and mortality rates globally.1 Seasonal influenza-associated deaths have increased in recent years, with an estimated of >600,000 fatalities annually.2 A significant proportion of hospitalized patients with influenza develop complications of acute respiratory distress syndrome, characterized by widespread alveolar-capillary injury, inflammation, edema, and parenchymal hemorrhage.3, 4, 5, 6, 7, 8 These pathologic manifestations are driven by virus-inflicted cytopathic effects as well as exaggerated host immune responses.9, 10, 11 Vaccination is the logical choice for controlling the virus. However, because of unrelenting emergence of new strains and their mutative ability, vaccination presents a major challenge during influenza outbreaks.12,13 In such cases, treatment primarily depends on antiviral therapy. Administration of antiviral drugs may not always be effective, as considerable lung pathology is mediated by exaggerated host-immune responses in addition to virus-inflicted cytotoxicity.14, 15, 16, 17Previously, we established that massive neutrophil influx, their induced neutrophil extracellular traps (NETs), and extracellular histones (ECHs) aggravate pulmonary pathology in severe influenza.18, 19, 20, 21, 22, 23 Aberrant neutrophil activity and accumulation of NETs are also documented in patients with severe influenza.24,25 Neutrophils are recruited to the site of injury/infection via chemokine signaling, mediated through chemokine receptors. Among various chemokine receptors, CXC chemokine receptor 2 (CXCR2) plays a critical role in modulating neutrophil functionality during influenza.26 Numerous clinical studies have also tested CXCR2 antagonists for their efficacy in reducing inflammation and organ injuries in acute and chronic diseases.27, 28, 29, 30, 31 Recently, human phase 2 trials evaluated the safety and efficacy of a CXCR2 antagonist, danirixin, alone or in combination with oseltamivir in influenza-infected patients.27,28 Although administration of danirixin was found to be safe and well-tolerated, no differences in the clinical scores were observed between patients given oseltamivir alone and those given danirixin plus oseltamivir.27 Furthermore, there was inconsistency in neutrophil numbers among different treatment groups. This inconsistency may be attributed to the absence of rational determination of the optimal timing and dosing of danirixin, to achieve the fine balance of suppressing excessive neutrophil influx, without compromising the beneficial host immunity by neutrophils. Moreover, the underlying mechanistic roles of targeting CXCR2 and its pathogenic association with influenza pneumonia have not been established.NETs are large extracellular web-like chromatin strands that were initially proposed to have a defense mechanism against invading pathogens.32 However, excessive release of NETs aggravates tissue injury and death, as reported in several disease conditions.33, 34, 35, 36 NETosis is regulated by various granule and nuclear proteins.37 Myeloperoxidase (MPO) and neutrophil elastase (NEs) are released from azurophilic granules, anchor chromatin scaffolds in NETs, and mediate histone degradation during NETosis.38 We reported earlier that blocking MPO decreases NETs, but signaling mechanisms in influenza-induced NETosis remain unclear.17,18 Herein, we evaluated the therapeutic efficacy of a CXCR2 antagonist, SCH527123 (2-hydroxy-N,N-dimethyl-3-[2-([(R)-1-(5-methyl-furan-2-yl)-propyl]amino)-3,4-dioxo-cyclobut-1-enylamino]-benzamide) alone or in combination with antiviral agent, oseltamivir (which inhibits viral neuraminidase and prevents progeny virus release from infected cells), in models of lethal influenza-infected mice and sublethal swine influenza-infected piglets. SCH527123 plus oseltamivir significantly improved survival in lethal influenza-challenged mice, and attenuated lung pathology in swine influenza-infected piglets. Thus, SCH5277123 plus oseltamivir represents a promising combination treatment against influenza pneumonia.  相似文献   
126.
In this second of three articles exploring Engel's biopsychosocial model, five case histories illustrate how psychological factors, sometimes related to organic trauma or illness, may precipitate psychiatric conditions. The patients’ disorders, and their management by a consultation-liaison team, demonstrate the interaction of biologic, psychological, and social systems in assessment and treatment of disease.  相似文献   
127.
128.
Since chlorine placement and the degree of chlorination of the biphenyl nucleus play an important role in the metabolism and ultimate elimination of polychlorinated biphenyls (PCBs), we have studied the metabolism of 4,4'-dichlorobiphenyl (4-DCB) by human hepatic microsomes. This low molecular weight PCB congener is substituted at the preferred site of metabolism (para-position). 4-DCB was metabolized by human microsomes with a Km of 0.43 microM and a Vmax of 1.2 pmoles/mg microsomal protein/min. Six metabolites were identified: 4,4'-dichloro-3,3'-biphenyldiol, 4'-chloro-3-biphenylol, 4'-chloro-4-biphenylol, 4,4'-dichloro-2-biphenylol, 4,4'-dichloro-3-biphenylol (most abundant), and 3,4'-dichloro-4-biphenylol. [14C]-4-DCB equivalents were found to covalently bind to microsomal protein. Addition of a 1 mM concentration of reduced glutathione decreased the degree of covalent binding. These data suggest that human microsomes metabolize this PCB through an arene oxide and that an "NIH shift" occurs. When UDPGA was added to the incubation, human microsomal glucuronosyltransferase catalyzed the formation of the glucuronide of the major metabolite, 4,4'-dichloro-3-biphenylol. These and previous in vitro results show that the biotransformation of PCBs by humans is governed by the same principles established for the in vivo biotransformation of PCBs by the rat, mouse and monkey. That is, PCBs without two adjacent unsubstituted carbon atoms are poorly metabolized and that an unsubstituted para-position facilitates metabolism.  相似文献   
129.
目的 使用文献计量学对国内外大学生艾滋病相关研究进行对比分析,旨在推动未来国内该领域的发展。方法 通过中国知网(CNKI)与Web of Science核心合集检索得1986—2021年国内外大学艾滋病研究的相关文献,借助VOSviewer及R软件对纳入研究的发表时间、作者及单位分布、热点内容与前沿趋势进行剖析。结果 国外相较国内研究起步较早,国内外总体发文量均呈上升趋势,美国占据相关领域英文研究的主导地位。《中国艾滋病性病》(257篇)与J AM COLL HEALTH(46篇)分别是载文最多的中英文杂志,各研究团体间的合作尚不够紧密。中文研究侧重不同教育方式于艾滋病防控的探索,英文研究则更关注于该群体“酒精使用”、“物质滥用”与“心理”等话题,防艾生活技能及暴露前预防(PrEP)等或成为未来研究趋势。结论 刊载大学生艾滋病的期刊类型较多,而高发文量期刊数较少且作者及机构间的合作有待加强,国内应给予该群体物质滥用及心理等方面更多关注,同时今后要加强对艾滋病监测与防艾生活技能方面的训练。  相似文献   
130.
目的 分析医学院校大学生宿舍人际关系对其抑郁情绪的影响,为促进大学生身心健康发展提供依据。方法 采用分层随机抽样法,抽取西南地区某医科大学的1215名在校大学生,采用流调用抑郁自评量表(CES-D)和感知亲密关系质量量表(PRQC)修改版进行问卷调查。采用t检验、方差分析和多元线性回归进行统计分析。结果 大学生CES-D量表平均得分14.25±9.11分,抑郁情绪检出率为24.5%,其中轻、中、重抑郁情绪检出率分别为18.3%、5.4%、0.8%。有抑郁情绪的大学生宿舍人际关系总得分及各维度得分均低于无抑郁情绪者(t=14.471,P<0.05),多元线性回归分析显示年级、家庭所在地、宿舍亲密度、宿舍信任度、宿舍氛围影响大学生抑郁情绪(P<0.05)。结论 宿舍人际关系对大学生抑郁情绪有影响,高校工作者应重视早期识别抑郁情绪的学生,关注学生的宿舍人际关系状况,提高大学生的心理健康水平。  相似文献   
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