首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1473篇
  免费   128篇
  国内免费   30篇
耳鼻咽喉   6篇
儿科学   42篇
妇产科学   14篇
基础医学   99篇
口腔科学   128篇
临床医学   124篇
内科学   161篇
皮肤病学   15篇
神经病学   87篇
特种医学   13篇
外科学   55篇
综合类   142篇
现状与发展   1篇
预防医学   550篇
眼科学   14篇
药学   71篇
  2篇
中国医学   22篇
肿瘤学   85篇
  2023年   19篇
  2022年   46篇
  2021年   134篇
  2020年   62篇
  2019年   54篇
  2018年   51篇
  2017年   52篇
  2016年   44篇
  2015年   50篇
  2014年   101篇
  2013年   134篇
  2012年   88篇
  2011年   97篇
  2010年   59篇
  2009年   56篇
  2008年   72篇
  2007年   62篇
  2006年   64篇
  2005年   47篇
  2004年   37篇
  2003年   32篇
  2002年   26篇
  2001年   21篇
  2000年   17篇
  1999年   15篇
  1998年   20篇
  1997年   9篇
  1996年   13篇
  1995年   9篇
  1994年   12篇
  1993年   10篇
  1992年   13篇
  1991年   7篇
  1990年   12篇
  1989年   6篇
  1988年   7篇
  1987年   8篇
  1985年   8篇
  1984年   6篇
  1983年   7篇
  1982年   7篇
  1981年   6篇
  1980年   6篇
  1979年   5篇
  1978年   6篇
  1977年   1篇
  1976年   4篇
  1975年   5篇
  1973年   1篇
  1971年   1篇
排序方式: 共有1631条查询结果,搜索用时 31 毫秒
1.
目的:调查本市区小学儿童感觉统合失调现状与不良行为及家庭因素的关系。方法:用感觉统合诊断量表和自制儿童生长发育调查表对1775名学龄儿童进行心理行为问题调查。结果:感觉统合轻度失调23.4%,重度失调13.5%,男童失调发和率(42.86%)明显高于女童(31.36%)P<0.0),前庭功能失衡发生率最高(21.30%);统合失调组儿童不良行为发生率高达64.38%明显高于统合正常组(31.11%)P<0.01,失调组不良行为各因子的发生率亦明显高于统合正常组P<0.01;学习能力不足儿童与父母文化程度和不同职业有关P<0.01。结论:儿童感觉纺合失调现状易成为成人心理障碍的潜在因素,应引起重视。  相似文献   
2.
The dietary history method was used to determine the total energy and macronutrient intake, the distribution of daily energy from the different meals and the energy contribution of various food groups, in a population of 299 boys, aged between 10 and 15 years. The effects of age, the social status of the father (SPS), the ponderal index, the importance of breakfast or lunch, and the level of energy intake on dietary indicators, were studied. In our population, energy intake increased with increasing age but the energy contribution of macronutrients did not vary. The diet of boys whose fathers were in the upper SPS classes differed from the diet of those boys whose fathers were manual workers: for example they consumed less energy and pastries, but more animal protein (in percentage of energy intake), more dairy products, and more fruit. The ponderal index was negatively related to energy intake but positively related to protein intake, especially from meat and meat products. The energy intake from protein, animal protein and the energy contribution of dairy products, meat and meat products, fish and vegetables was lower among large eaters than among small eaters. The energy contribution of pastries, sugar and sweets was higher among large eaters.
Similarily, the energy intake from morning and evening snacks was also higher among large eaters. It should be noted that boys who had a substantial breakfast took in less energy from all other meals (including snacks and main meals). Such informaton is necessary in order to develop an effective health programme.  相似文献   
3.
目的 了解学生在遭遇劣性刺激时的心理和行为反应,为心理干预提供依据.方法 运用心理调查表对2013名学生进行问卷调查与统计分析.结果 情绪体验有悲观泄气、悲痛欲绝、难过很久,行为意向有报复、骂人、打人、杀人、出走、自杀,部分演化为非理性行为;在应对策略上依次为自己调适、求助朋友、憋在心里、随意发泄、逃避、求助家长、求助老师、求助咨询、攻击.在性别、年龄上有差异.结论 不良行为的预防要注意情绪调节与理智应对的训练.  相似文献   
4.
14 3 3蛋白是Moore和Pere于 196 7年发现的 ,当时他们认为 14 3 3蛋白是脑所特有的一种酸性蛋白 ,并依据其在DEAE 纤维素色谱上的组分数以及在淀粉凝胶电泳中的迁移位置而命名为 14 3 3蛋白。但随后的大量研究表明14 3 3蛋白在所有的真核细胞中均有表达 ,是一个调节蛋白家族 ,能与许多功能不同的信号蛋白结合 ,例如蛋白激酶Raf 1、KSR 1、Bcr、Ca2 +/钙调蛋白激酶、PKC、蛋白磷酸酶cdc2 5c、促凋亡蛋白BAD、抗凋亡蛋白A2 0 、跨膜蛋白受体GA等。这就说明 14 3 3蛋白在信号传导、细胞周期调控、细胞凋亡等过程中具有极其重要的…  相似文献   
5.
6.
Macrophages play a major role in HIV-1 persistence. In the present paper, we demonstrate that the absence of apoptosis in HIV-1-infected primary human monocyte-differentiated macrophages (MDM) correlates with an increase in anti-apoptotic (Bcl-2 and Bcl-x(L)) and a decrease in pro-apoptotic (Bax and Bad) proteins. This is associated with macrophage activation as shown by tumor necrosis factor (TNF) production and NF-kappaB activation upon infection. TNF production was shown to be involved in the upregulation of Bcl-2 and Bcl-x(L) because this increase was abolished by an anti-TNF anti-serum or an inhibitor of TNF synthesis. In parallel, inhibition of TNF production induced an increase in the number of apoptotic cells. Furthermore, using an inhibitor of NF-kappaB activation, we demonstrated that TNF-induced upregulation of Bcl-x(L) and Bcl-2 occurs, respectively, through a NF-kappaB-dependent and an NF-kappaB-independent pathway.  相似文献   
7.
Background Occupational allergic respiratory symptoms in coffee workers have been frequently reported, but the ultimate cause of sensilization is still debated, castor bean being considered besides green coffee beans. Atopy and cigarette smoking have been suggested as promoting factors of sensitizalion for several occupational allergens. Objective This study was carried out to assess the prevalence of allergic respiratory symptoms and of sensitization to both green coffee beans and castor bean in the whole workforce of a coffee manufacturing plant. Furthermore we wanted to ascertain both the presence of castor bean antigens in the settled dust of the green coffee beans warehouse and the possible crossreactivity between the two beans. Meanwhile, the effect of smoking and atopy was considered. Method: Two-hundred and eleven workers were examined. A questionnaire on oculorhinitis and asthma was administered and skin-prick tests for green coffee beans, castor bean and 15 common inhalant allergens were carried out. Isoelectric focusing, isoelectric focusing immunoblot and radioallergosorbent assay (RAST) inhibition were performed on samples of settled environmental dust from the green coffee area, as well as on castor bean and green coffee beans. Results Ten per cent of the workers complained of oculorhinitis alone and 16% of asthma (nearly always associated with oculorhinitis). The overall prevalence of skin-sensitization was: 15% for green coffee beans, 22% for castor bean, 22% for common allergens. Evidence of sensitization to occupational allergens was more common in smokers, with a more than twofold increase in relative risk. The strong association between skin positivity to common and occupational allergens suggests that atopy acts as an enhancing host factor towards occupational sensitization. The analysis of the dust confirmed the presence of castor bean antigens. Conclusion Our findings indicate that castor bean is the major cause of occupational sensitization among coffee workers, whereas smoking and atopy act as enhancing factors.  相似文献   
8.
目的 探讨学龄前儿童不良身体姿态与生活习惯的相关性,为该群体不良身体姿态的预防提供参考依据。方法 采用Body - Style身体姿态评估测试仪(Model.S - 8.0)和《学龄前儿童生活习惯调查问卷》对整群随机抽取的北京市4所幼儿园 406名学龄前儿童进行体态评估和生活习惯调查。使用χ2检验和logistic回归分析进行统计分析。结果 学龄前儿童体态测评得分为(21.98±3.01),不良体态检出率为75.86%,其中骨盆前倾、高低肩、O/X型腿检出率较高,占比分别为39.41%、46.80%、58.37%;不良体态检出率在性别(χ2 = 10.28)、年龄(χ2 = 16.57)、BMI(χ2 = 7.46)存在组别差异且均具有统计学意义(P<0.05),具体表现为女童(79.24%)高于男童(72.16%),3~<4岁组(73.02%) 4~<5岁组(75.00%) 5~6岁(79.86%)具有随年龄增长递增的特点,肥胖儿童(86.36%)不良体态检出率相对较高;体态发育与生活习惯具有相关性,“每天参加体育锻炼”(OR = 2.014,95%CI:1.712~2.426)、“视屏时间<2 h”(OR = 1.632,95%CI:1.266~1.527)、“睡眠时间≥6 h”(OR = 1.425,95%CI:1.266~1.624)、“基本每天都吃牛乳奶制品”(OR = 1.067,95%CI:0.906~1.146)对儿童体态发育具有积极影响。结论 学龄前儿童生活习惯对体态健康具有显著影响,通过改善体力活动、饮食习惯和睡眠时间,促进其体态健康发展。  相似文献   
9.
BackgroundTo achieve sustainable weight loss and healthy lifestyle changes is a huge challenge in the fight against obesity. The objective of this study was to evaluate the effectiveness to promote weight loss maintenance and healthy lifestyle habits of a group educational intervention program, Group Intervention in OBEsity (IGOBE), compared with a usual care therapy to lose weight.MethodsPatients with obesity (n = 437; 18.5% men, 18–77 years and 40.4 ± 6.7 kg/m2) were randomised into two groups to follow a prospective interventional real-life study: a control group (CG), treated with usual clinical practice, and an intervention group (IG), in which the patients participate in a group intervention program on healthy lifestyle habits with weekly sessions for six weeks, after which a re-evaluation was made at six months and at 12 months of follow-up. After finishing the study dropout rates were 44.6% in CG and 43.4% in IG. Anthropometric, dietetic habits and body composition data were analysed in both groups at the pre-intervention and post-interventions of the subjects by completer’s analysis.ResultsAt 12 months of following IGOBE program, the IG achieved greater weight loss (–7.1% of the initial weight) than the CG, which exhibited a weight gain (3.0% of the initial weight). The body weight change induced in the IG was accompanied by a reduction in fat mass, particularly visceral fat and waist circumference. Relevantly, the IG adhered to a healthy dietary pattern and changed its eating habits, which correlated with the improvement in body weight.ConclusionsIntensive educational group treatment that induces a change of eating habits and adherence to healthy dietary pattern is more effective in a long-term to counteract obesity traits than a standard treatment performed individually. The IGOBE program could be a cost-effective practice in the clinical management of obesity.  相似文献   
10.
An appropriate balanced diet and dietary patterns are important at every stage of life, but in the case of young patients with type 1 diabetes mellitus (T1DM), it is especially crucial during the COVID-19 pandemic. The aim of the study was to assess health and nutritional behaviors, mainly adherence to the Mediterranean diet (MD), during the second wave of the COVID-19 pandemic in Poland among women with T1DM, and to compare them with a healthy population. This survey (based on a questionnaire) was conducted in December 2020 and included 219 young women, healthy (n = 106) and with T1DM (n = 113), from northeast Poland. Over 30% of the study group admitted that they did not engage in any physical activity. A large proportion declared that their screen time was 5–7 h a day (48% in control and 40% in T1DM group). High intakes of sweet-beverages, sweets and red meat, but also low intakes of olive oil, fish and nuts were observed. The vast majority of participants (60% vs. 71%) were moderately adherent to the Mediterranean Diet Adherence Screener (MEDAS). The study demonstrated that despite the similarity between the behaviors of healthy people and those with T1DM, negative health and nutritional practices, such as low physical activity, long screen time, medium and high levels of stress and inappropriate eating habits were observed.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号