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   4715篇
  免费   349篇
  国内免费   51篇
耳鼻咽喉   15篇
儿科学   32篇
妇产科学   23篇
基础医学   1005篇
口腔科学   47篇
临床医学   314篇
内科学   263篇
皮肤病学   21篇
神经病学   784篇
特种医学   52篇
外科学   115篇
综合类   1001篇
预防医学   566篇
眼科学   23篇
药学   286篇
  2篇
中国医学   534篇
肿瘤学   32篇
  2024年   24篇
  2023年   55篇
  2022年   115篇
  2021年   181篇
  2020年   171篇
  2019年   123篇
  2018年   120篇
  2017年   190篇
  2016年   222篇
  2015年   158篇
  2014年   336篇
  2013年   343篇
  2012年   292篇
  2011年   354篇
  2010年   274篇
  2009年   273篇
  2008年   281篇
  2007年   282篇
  2006年   238篇
  2005年   158篇
  2004年   119篇
  2003年   126篇
  2002年   116篇
  2001年   88篇
  2000年   71篇
  1999年   38篇
  1998年   46篇
  1997年   31篇
  1996年   35篇
  1995年   28篇
  1994年   23篇
  1993年   17篇
  1992年   17篇
  1991年   13篇
  1990年   16篇
  1989年   11篇
  1988年   14篇
  1987年   10篇
  1986年   6篇
  1985年   14篇
  1984年   14篇
  1983年   11篇
  1982年   10篇
  1981年   7篇
  1980年   5篇
  1979年   6篇
  1977年   6篇
  1976年   9篇
  1975年   5篇
  1974年   4篇
排序方式: 共有5115条查询结果,搜索用时 0 毫秒
81.
目的探讨在押男性犯罪嫌疑人与正常人群大五人格、应对方式的差异。方法对78名在押男性犯罪嫌疑人(实验组)及54名对照组男性(对照组)进行问卷调查。结果①利他性与道德感维度差异显著;②实验组积极应对显著低于正常组,但消极应对差异不大;⑧实验组与对照组在人格与心理健康的相互关系上具有不同的特点。结论青年男性在押犯罪嫌疑人与正常青年男性在大五人格、应对方式上存在差异。  相似文献   
82.
Background: Five of the most abundant human milk oligosaccharides (HMOs) in human milk are 2′-fucosyllactose (2′-FL), 3-fucosyllactose (3-FL), lacto-N-tetraose (LNT), 3′-sialyllactose (3′-SL) and 6′-sialyllactose (6′-SL). Methods: A randomized, double-blind, controlled parallel feeding trial evaluated growth in healthy term infants fed a control milk-based formula (CF; n = 129), experimental milk-based formula (EF; n = 130) containing five HMOs (5.75 g/L; 2′-FL, 3-FL, LNT, 3′-SL and 6′-SL) or human milk (HM; n = 104). Results: No significant differences (all p ≥ 0.337, protocol evaluable cohort) were observed among the three groups for weight gain per day from 14 to 119 days (D) of age, irrespective of COVID-19 or combined non-COVID-19 and COVID-19 periods. There were no differences (p ≥ 0.05) among the three groups for gains in weight and length from D14 to D119. Compared to the CF group, the EF group had more stools that were soft, frequent and yellow and were similar to the HM group. Serious and non-serious adverse events were not different among groups, but more CF-fed infants were seen by health care professionals for illness from study entry to D56 (p = 0.044) and D84 (p = 0.028) compared to EF-fed infants. Conclusions: The study demonstrated that the EF containing five HMOs supported normal growth, gastrointestinal (GI) tolerance and safe use in healthy term infants.  相似文献   
83.
目的 了解宜昌市城区居民急性心肌梗死(Acute Myocardial Infarction,AMI)的流行特征,为制定有针对性的防治工作提供依据.方法 利用宜昌市健康大数据平台2015-2019年监测数据,采用年估计百分比评价AMI的发病率、死亡率变化趋势.结果 2015-2019年宜昌市AMI新发病例1 976人,...  相似文献   
84.
藏象学的发展有赖于两个方面进步的推动,即一方面长期临床实践成就的积累是藏象学理论发展的原动力;另一方面则临床成就必须经哲学思辨的系统改造后,才能真正地融合到理论体系当中。"五藏"的观念是伴随着"五行"理论的成熟而发展起来的,以《黄帝内经》为代表的中医藏象学理论体系,在很大程度上是参照了两汉经学思想的理论框架创建的。《内经》最重要的贡献,是要将医学实践长期积累的各种原始经验与知识,经过精心选择与改造后,系统地整合到设计好的理论模型当中,而最终完成藏象学理论体系的构建。在藏象学理论体系的构建过程中,"象"的思想占有非常重要的地位,先天的框架与后天的经验均被抽象为"象"的形式,再经思辨方法的改造而成。  相似文献   
85.
目的观察中医五联疗法治疗肝性脑病的,临床疗效。方法将肝性脑病患者65例随机分为治疗组34例与对照组31例,均予常规西药和中药汤剂口服治疗,治疗组加中药静脉滴注、中药灌肠、中药肝区热敷、中药穴位敷贴五联疗法。比较两组患者精神意识、智力及扑翼样震颤的改善情况,治疗前后总胆红素、血氨及凝血酶原时间变化情况。结果治疗组和对照组总有效率分别为76.47%、51.61%,治疗组疗效显著优于对照组(P〈0.05);两组患者治疗后总胆红素、血氨及凝血酶原时间均显著下降(P〈0.05),且治疗组在降低凝血酶原时间、血氨方面显著优于对照组(P〈0.05)。结论中医五联疗法发挥了中药综合治疗的优势,疗效显著,值得推广。  相似文献   
86.
目的 通过对南昌市一起农村新型冠状病毒肺炎聚集性疫情调查,了解农村疫情传播可能的危险因素,分析和比较确诊病例和无症状感染者的传染性。 方法 通过流行病学调查,结合大数据轨迹开展病例调查,用病例关系示意图展示传播关系。结果 确诊病例和无症状感染者的密切接触者续发率分别为45.45%和12.50%,两者无统计学差异(P=0.077),罹患率分别为27.27%和0%,两者有统计学差异(P=0.025);核酸全员筛检前后新冠病毒感染率分别为0.49%和0%,两者有统计学差异(〖XC小五号.EPS;P〗=7.09,P=0.008);确诊病例发病前5天和无症状感染者具有传染性;农村居民串门聊天、聚众打牌等行为可能促进农村疫情的传播。结论 此次疫情因病例B引起,轨迹大数据分析可帮助寻找传染源;无症状感染者传染性可能弱于确诊病例。  相似文献   
87.
程汇  刘婕妤  陈孜  + 《成都医学院学报》2024,19(3):515-518+523
目的 了解留守因素、家庭关系对留守中学生人格的影响。方法 于2019-2022年采用《艾森克人格问卷》少年版和《家庭亲密度与适应性量表》对眉山市某县级中学1 424名中学生进行调查。结果 纳入的受访者中,616名为留守中学生(占43.26%)。除了人格的精神质维度外,留守与非留守中学生在人格的其余维度及家庭关系的亲密度、适应性两个维度得分比较,差异有统计学意义(P<0.05)。结构方程模型分析显示,在留守初中生中,母亲外出时个体年龄对家庭亲密度有正向影响,路径系数为0.169;家庭亲密度对精神质与神经质有正向影响,路径系数分别为0.310、0.296;父亲在外时间长短对神经质有负向影响,路径系数为-0.146(P<0.05)。在留守高中生中,父亲外出时个体年龄对人格中的内外向有负向影响,路径系数为-0.111;母亲外出时个体年龄对精神质有负向影响,路径系数为-0.125;父亲在外时间长短对家庭亲密度、家庭适应性有负向影响,路径系数分别为-0.146、-0.163;家庭亲密度对精神质、神经质有正向影响,路径系数分别为0.253、0.266;家庭适应性对内外向有负向影响,路径系数为-0.241(P<0.05)。结论 留守经历会影响中学生的人格和家庭关系,但留守初中生和高中生在留守因素、家庭关系对人格特征的影响有所不同。  相似文献   
88.
This study provides a quantitative synthesis of the prospective associations between personality traits (neuroticism, extraversion, openness, agreeableness, conscientiousness) and the risk of incident Alzheimer’s disease and related dementias. We conducted five separate meta-analyses with 8–12 samples (N = 30,036 to 33,054) that were identified through a systematic literature search following the MOOSE guidelines. Higher neuroticism (HR = 1.24, 95% CI [1.17, 1.31]) and lower conscientiousness (HR = 0.77, 95% CI [0.73, 0.81]) were associated with increased dementia risk, even after accounting for covariates such as depressive symptoms. Lower extraversion (HR = 0.92, 95% CI [0.86, 0.97]), openness (HR = 0.91, 95% CI [0.86, 0.96]), and agreeableness (HR = 0.90, 95% CI [0.83, 0.98]) were also associated with increased risk, but these associations were less robust and not significant in fully adjusted models. No evidence of publication bias was found. The strength of associations was unrelated to publication year (i.e., no evidence of winner’s curse). Meta-regressions indicated consistent effects for neuroticism, openness, and conscientiousness across methods to assess dementia, dementia type, follow-up length, sample age, minority, country, and personality measures. The association of extraversion and agreeableness varied by country. Our findings indicate robust associations of neuroticism and conscientiousness with dementia risk.  相似文献   
89.
Hydrazine has been described as a mutagenic, probable human carcinogen. It is mutagenic in in vitro systems such as bacterial reverse mutation (Ames) tests and some yeast systems, as well as in in vivo systems with drosophila. It was shown to cause chromosome damage both in vitro and in vivo but was negative in some well‐validated mammalian mutation systems such as CHO HPRT assays. Importantly, there is only one in vivo gene mutation test reported, which was negative. Our objective was to determine if hydrazine is mutagenic in mammalian test systems. Thus, we conducted an in vitro gene mutation test in Muta?Mouse lung epithelial cells (FE1 cell assay) and a regulatory‐compliant in vivo Big Blue® mouse test. Consistent with previous reports, an additional six‐well Ames assay showed that hydrazine was mutagenic to bacteria. The FE1 cell assay was negative in conditions with and without metabolic activation when tested to cytotoxicity limits. In the Big Blue® mouse study, female mice received dosages of hydrazine up to 10.9 mg/kg via drinking water for 28 days. This dose is comparable to a dose used in a carcinogenicity study where female mice had significant increases in hepatocellular adenoma at 11.5 mg/kg. There were no increases in mutant frequency in liver and lung, two tissues sensitive to the carcinogenic effects of hydrazine in mice. Our research shows that hydrazine is not mutagenic in mammalian cells either in vitro or in vivo, indicating mutagenicity may not play a role in the carcinogenicity of hydrazine.  相似文献   
90.
ObjectivesTo develop an experimental protocol to study the vocal effort generated by introducing barriers to communication, and its relationship with certain personality traits.Material and methodsThe experimental protocol consisted of an interactive game in which the subject gave an investigator instructions to adopt various body positions (semi-directed communication situation). The Control situation included no constraints on communication. Then a Distance Constraint (increased distance between subject and investigator) and a Time Constraint (generation of performance stress by putting the subject in competition with others) were introduced. The vocal parameters studied comprised vocal intensity and fundamental frequency in the middle of the vowel of 3 target phonemes. Subjects also took the NEO FFI-R personality test.ResultsThe study included 41 women aged between 18 and 52 years. Vocal intensity and fundamental frequency increased significantly with the introduction of the constraints (P < 0.05), intensity passing from 75.5 dB to 81.8 dB and frequency from 249.4 Hz to 335.8 Hz. No correlations were found between these changes and results for the various personality traits.ConclusionsThis ecological protocol enables the impact of both physical and emotional obstacles to communication to be studied. No correlations between vocal effort and personality traits emerged. A larger-scale study would be necessary to analyze the continuum between vocal effort and vocal forcing, to improve speech therapy for dysfunctional dysphonia.  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