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   8229篇
  免费   975篇
  国内免费   128篇
耳鼻咽喉   61篇
儿科学   361篇
妇产科学   109篇
基础医学   829篇
口腔科学   546篇
临床医学   762篇
内科学   1759篇
皮肤病学   195篇
神经病学   997篇
特种医学   68篇
外科学   466篇
综合类   625篇
现状与发展   2篇
预防医学   1592篇
眼科学   423篇
药学   303篇
  2篇
中国医学   13篇
肿瘤学   219篇
  2024年   27篇
  2023年   174篇
  2022年   223篇
  2021年   353篇
  2020年   359篇
  2019年   385篇
  2018年   361篇
  2017年   354篇
  2016年   390篇
  2015年   345篇
  2014年   463篇
  2013年   691篇
  2012年   466篇
  2011年   455篇
  2010年   385篇
  2009年   381篇
  2008年   414篇
  2007年   381篇
  2006年   380篇
  2005年   309篇
  2004年   263篇
  2003年   241篇
  2002年   243篇
  2001年   167篇
  2000年   126篇
  1999年   111篇
  1998年   96篇
  1997年   95篇
  1996年   91篇
  1995年   68篇
  1994年   70篇
  1993年   57篇
  1992年   64篇
  1991年   41篇
  1990年   34篇
  1989年   35篇
  1988年   27篇
  1987年   23篇
  1986年   37篇
  1985年   34篇
  1984年   24篇
  1983年   14篇
  1982年   15篇
  1981年   15篇
  1980年   9篇
  1979年   9篇
  1978年   6篇
  1977年   7篇
  1976年   4篇
  1972年   4篇
排序方式: 共有9332条查询结果,搜索用时 15 毫秒
91.
The prevalence of nocturia among Japanese community-dwelling adults was associated with insomnia, taking into account other correlates of insomnia.  相似文献   
92.
BACKGROUND: Information on cancer prevalence is either absent or largely unavailable for central European countries. MATERIALS AND METHODS: Austria, Germany, The Netherlands, Poland, Slovakia, Slovenia and Switzerland cover a population of 13 million inhabitants. Cancer registries in these countries supplied incidence and survival data for 465 000 cases of cancer. The prevalence of stomach, colon, rectum, lung, breast, cervix uteri, corpus uteri and prostate cancer, as well as skin melanoma, Hodgkin's disease, leukaemia and all malignant neoplasms combined was estimated for the end of 1992. RESULTS: A large heterogeneity was observed within central European countries. For all cancers combined, estimates ranged from 730 per 100 000 in Poland (men) to 3350 per 100 000 in Germany (women). Overall cancer prevalence was the highest in Germany and Switzerland, and the lowest in Poland and Slovenia. In Slovakia, prevalence was higher than average for men and lower than average for women. This was observed for almost all ages. As shown by incidence data, breast cancer was the most frequent malignancy among women in all countries. Among men, prostate cancer was the leading malignancy in Germany, Austria and Switzerland, and lung cancer was the major cancer in Slovenia, Slovakia and Poland. The Netherlands had a high prevalence of both prostate and lung cancer. Time-related magnitude of prevalence within each country and the variability of such proportions across the countries has been estimated and cancer prevalence is given by time since diagnosis (1 year, 1-5 years, 5-10 years, >10 years) for each site. The weight of 1-year prevalence (248 per 100 000 among men and 253 per 100 000 among women) was <15% of total prevalence. Prevalent cases between 1 and 5 years since diagnosis represented between 22% and 34% of the total prevalence. Prevalent cases diagnosed from 5 to 10 years before (335 per 100 000 for men and 505 per 100 000 for women) represented between 17% and 23% of prevalent cancers. Finally, long-term cancer prevalence (diagnosed >10 years before), reflecting long-term survival, and number of people considered as cured from cancer were 490 per 100 000 for men and 1028 per 100 000 for women, with a range between 26% (The Netherlands, men) and 50% (Slovakia, women). CONCLUSION: It is clear from observing countries in Central Europe, that high cancer prevalence is associated with well-developed economies. This burden of cancer could be interpreted as a paradoxical effect of better treatments and thereby survival. It could also be taken as a sign for not being satisfied with the advances in treating patients diagnosed with cancer, and for supporting more primary prevention.  相似文献   
93.
The frequency and treatment of children with chronic idiopathic thrombocytopenic purpura in Sweden were characterized using a national enquiry based on a questionnaire. Seventy-five children diagnosed as having chronic idiopathic thrombocytopenic purpura on 1 September 1993 were identified. The prevalence in children between 0.5 and 15.5 years of age was calculated to be 4.6/100 000. The median age at the time of diagnosis was 5 years and the male/female ratio was 1:1.2. Almost half of the patients (43%) were not treated at all during the disease. Steroids (43%) and intravenous immunoglobulin (25%) were most commonly used. Only two children were splenectomized.  相似文献   
94.
Objective To determine lactose metabolism and lactase activity in Chinese children of diff erent ages, prevalence of lactase deficiency (LD), and lactose intoleran ce (LI).
Methods
All 1168 healthy subjects between 3 and 13 years were recruited from schools in four large cities in China. They were screened by a 25 g lactose tolerance tes t. Some subjects were challenged with 50 g milk powder on different days. Bot h indicators, the expiratory H2 concentration and intolerance symptoms, were a nalyzed.

Results
LD occurred in 38.5% of children in the 3-5 year age group, and 87% of the 7-8 year and 11-13 year old groups. The age of occurrence for LD may be at 7-8 years among Chinese children. The prevalence of LI among Chinese children w as 12.2% at age 3-5 years, 33.1% at age 7-8 years, and 30.5% at age 11-13 yea rs, respectively.

Conclusion
The results demonstrate that LD is very common in Chinese children from these fo ur cities. LD and LI have a dose dependent response: lactose absorption and sym ptoms are based on lactase activity. The relationship between breast feeding hi story (or the history of cow milk intake) and lactase activity among Chinese chi ldren has not been established.
  相似文献   
95.
对上海和青岛郊区已婚育龄妇女节育状况的调查发现,25岁以下的已婚妇女避孕现用率最低,有孩子的妇女现用率高.研究还发现给予宣教和引进新避孕方法进行干预后.避孕现用率比干预前提高(OR=1.4~1,5),干预后使用皮下埋植剂和新型IUD(T型)的妇女增多,提示干预性措施是有效果的.  相似文献   
96.
To inform New York City’s (NYC’s) tobacco control program, we identified the neighborhoods with the highest smoking rates, estimated the burden of second-band smoke exposure, assessed the early response to state taxation, and examined cessation practices. We used a stratified random design to conduct a digit-dialed telephone survey in 2002 among 9,674 New York City adults. Our main outcome measures included prevalence of cigarette smoking, exposure to second-hand smoke, the response of smokers to state tax increases, and cessation practices. Even after controlling for sociodemographic factors (age, racelethnicity, income, education, marital status, employment status, and foreign-born status) smoking rates were highest in Central Harlem and in the South Bronx. Sixteen percent of nonsmokers reported frequent exposure to second-hand smoke at home or in a workplace. Among smokers with a child with asthma, only 33% reported having a no-smoking policy in their homes. More than one fifth of smokers reported reducing the number of cigarettes they smoked in response to the state tax increase. Of current smokers who tried to quit, 65% used no cessation aid. These data were used to inform New York City’s smoke-free legislation, taxation, public education, and a free nicotine patch give-away program. In conclusion, large, local surveys can provide essential data to effectively advocate for, plan, implement, and evaluate a comprehensive tobacco control program. Dr. Mostashari (the guarantor) made substantial contributions to the conception, design, and supervision of this paper, the analysis and interpretation of data, the drafting of the paper, critical revisions of the paper for important intellectual content, and the acquisition of data and funding for this research. Dr. Kerker made substantial contributions to the analysis and interpretation of data, the drafting of the paper and critical revisions of the paper for important intellectual content. Ms. Hajat made substantial contributions to the acquisition of data and critical revisions of the paper for important intellectual content. Dr. Miller made substantial contributions to the conception of this paper and critical revisions of the paper for important intellectual content. Dr. Frieden made substantial contributions to the conception, design, and supervision of this paper and critical revisions of the paper for important intellectual content.  相似文献   
97.
The assessment of relevance of toxicological testing was compared with approaches of diagnostic medicine, a discipline that faces a comparable situation. Considering the work of a toxicologist as setting a diagnosis for compounds, assessment tools for diagnostic tests were transferred to toxicological tests. In clinical diagnostics, test uncertainty is well accepted and incorporated in this assessment. Furthermore, prevalence information is considered to evaluate the gain in information resulting from the application of a test. Several common toxicological scenarios, in which test uncertainty and prevalence are combined, are discussed including the interdependence of test accuracy, prevalence and predictive values or the sequential application of a screening and a confirmatory test. In addition, real prevalences derived from prevalences determined by an imperfect test are presented. We conclude that information on prevalences of toxic health effects is required to allow a complete assessment of the relevance of toxicological test. In this process, lessons can be learned from evidence-based approaches in clinical diagnostics.  相似文献   
98.
目的 了解昆明地区成年人 2型糖尿病患病现状及其特征。方法 采用多阶段分层随机抽样方法对昆明市 14县区 2 0岁及以上的 5 6 2 6名城镇常住居民进行调查。结果 调查人群 2型糖尿病患病率为 2 70 % (标化患病率为 1 5 1% ) ,其中男性患病率 2 17% ,女性患病率为 3 10 % ,女性患病率高于男性 ,且中心城区居民 2型糖尿病患病率高于郊区 ,远高于郊县居民。年龄、超重肥胖、文化程度等是影响 2型糖尿病发生的重要因素。结论  2型糖尿病是影响昆明城市居民尤其是中老年人健康的重要公共卫生问题 ,应进一步加强预防控制工作。  相似文献   
99.
老年人自评状况和社会支持与老年抑郁症患病率   总被引:6,自引:0,他引:6  
目的 探讨老年人抑郁症患病率与自评状况及社会支持的关系。方法 就调查的1736名老年人的自评状况以及社会支持分别进行单因素的患病率分析,再进行多因素Logistic回归分析。结果 自评健康状况差、患有老年慢性支气管炎和癌症、健康恶化都可以增加老年抑郁症的患病率。  相似文献   
100.
老年人躯体疾病与老年抑郁症患病率   总被引:7,自引:0,他引:7  
目的 探讨老年人躯体疾病与抑郁症患病率的关系。方法 就调查的1736名老年人的自评健康情况、躯体患病情况以及健康恶化情况分别进行单因素的患病率分析,再进行多因素Logistic回归分析。结果 自评健康差、患有老年慢性支气管炎和癌症、健康恶化都可以提高老年抑郁症的患病率。  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