全文获取类型
收费全文 | 23052篇 |
免费 | 1900篇 |
国内免费 | 299篇 |
专业分类
耳鼻咽喉 | 71篇 |
儿科学 | 787篇 |
妇产科学 | 424篇 |
基础医学 | 1140篇 |
口腔科学 | 812篇 |
临床医学 | 3105篇 |
内科学 | 4562篇 |
皮肤病学 | 478篇 |
神经病学 | 1089篇 |
特种医学 | 521篇 |
外国民族医学 | 1篇 |
外科学 | 1380篇 |
综合类 | 2127篇 |
现状与发展 | 7篇 |
预防医学 | 4806篇 |
眼科学 | 314篇 |
药学 | 1702篇 |
21篇 | |
中国医学 | 657篇 |
肿瘤学 | 1247篇 |
出版年
2024年 | 62篇 |
2023年 | 441篇 |
2022年 | 719篇 |
2021年 | 1071篇 |
2020年 | 1287篇 |
2019年 | 997篇 |
2018年 | 989篇 |
2017年 | 887篇 |
2016年 | 896篇 |
2015年 | 790篇 |
2014年 | 1477篇 |
2013年 | 2318篇 |
2012年 | 1132篇 |
2011年 | 1310篇 |
2010年 | 1107篇 |
2009年 | 1040篇 |
2008年 | 1034篇 |
2007年 | 1028篇 |
2006年 | 1022篇 |
2005年 | 843篇 |
2004年 | 686篇 |
2003年 | 628篇 |
2002年 | 560篇 |
2001年 | 426篇 |
2000年 | 329篇 |
1999年 | 317篇 |
1998年 | 274篇 |
1997年 | 203篇 |
1996年 | 227篇 |
1995年 | 164篇 |
1994年 | 124篇 |
1993年 | 132篇 |
1992年 | 97篇 |
1991年 | 75篇 |
1990年 | 73篇 |
1989年 | 72篇 |
1988年 | 78篇 |
1987年 | 52篇 |
1986年 | 47篇 |
1985年 | 39篇 |
1984年 | 36篇 |
1983年 | 30篇 |
1982年 | 25篇 |
1981年 | 34篇 |
1980年 | 21篇 |
1979年 | 16篇 |
1978年 | 9篇 |
1977年 | 8篇 |
1976年 | 9篇 |
1975年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Daniel J. Diekema MD Kristi J. Ferguson PhD Dr. Bradley N. Doebbeling MD MS 《Journal of general internal medicine》1995,10(1):1-6
PURPOSE: To evaluate the acceptance rate and motivation for acceptance of hepatitis B virus (HBV) vaccine among pre-clinical medical
and physician assistant (PA) students in comparison with similar data obtained from resident and staff physicians.
METHODS: A cross-sectional survey of all second-year medical and PA students (n=170) at the University of Iowa College of Medicine was conducted in Spring 1992, requesting demographic data, preventive
health measure use, and reasons for HBV vaccine acceptance. Responses were compared with data obtained from resident and staff
physicians during a concurrent hospital-wide survey. Rates of vaccine acceptance and use of other preventive health measures
were compared across the physician groups. Factor analysis was performed to examine reasons for vaccine acceptance among the
students.
RESULTS: The questionnaire was completed by 162 of the 170 students (95%). Nearly all (99%) of the eligible students had received
at least one dose of the HBV vaccine. Vaccine acceptance rates were significantly higher among the students than among either
the resident or the staff physicians (p=0.003, p<0.0001, respectively). Influenza vaccine acceptance and seat belt use were
significantly higher among the resident and staff physicians than they were among the students. The students attributed their
high HBV vaccine acceptance rate to the recommendations of authority figures. Threat of illness and issues of vaccine safety
and efficacy were relatively unimportant among the students, though the residents and staff physicians reported threat of
illness to be an important motivator for vaccination.
CONCLUSIONS: Excellent HBV vaccine acceptance rates may be achieved among preclinical medical and PA students. Recommendations of authority
figures are important motivators for HBV vaccine acceptance among students.
Presented in part at the annual meeting of the Society for Hospital Epidemiology of America, New Orleans, LA, March 20–22,
1994.
Dr. Doebbeling is the recipient of a Special Emphasis Research Career Award (SERCA), grant number 1 KO1 OH00131-01, from the
National Institute for Occupational Safety and Health (NIOSH). The contents of this article are solely the responsibility
of the authors and do not necessarily represent the official views of NIOSH. 相似文献
992.
Friedman SM Munoz B West SK Rubin GS Fried LP 《Journal of the American Geriatrics Society》2002,50(8):1329-1335
OBJECTIVES: Previous cross-sectional studies have shown a correlation between falls and fear of falling, but it is unclear which comes first. Our objectives were to determine the temporal relationship between falls and fear of falling, and to see whether these two outcomes share predictors. DESIGN: A 20-month, population-based, prospective, observational study. SETTING: Salisbury, Maryland. Each evaluation consisted of a home-administered questionnaire, followed by a 4- to 5-hour clinic evaluation. PARTICIPANTS: The 2,212 participants in the Salisbury Eye Evaluation project who had baseline and 20-month follow-up clinic evaluations. At baseline, subjects were aged 65 to 84 and community dwelling and had a Mini-Mental State Examination score of 18 or higher. MEASUREMENTS: Demographics, visual function, comorbidities, neuropsychiatric status, medication use, and physical performance-based measures were assessed. Stepwise logistic regression analyses were performed to evaluate independent predictors of falls and fear of falling at the follow-up evaluation, first predicting incident outcomes and then predicting fall or fear-of-falling status at 20 months with baseline falling and fear of falling as predictors. RESULTS: Falls at baseline were an independent predictor of developing fear of falling 20 months later (odds ratio (OR) = 1.75; P <.0005), and fear of falling at baseline was a predictor of falling at 20 months (OR = 1.79; P <.0005). Women with a history of stroke were at risk of falls and fear of falling at follow-up. In addition, Parkinson's disease, comorbidity, and white race predicted falls, whereas General Health Questionnaire score, age, and taking four or more medications predicted fear of falling. CONCLUSION: Individuals who develop one of these outcomes are at risk for developing the other, with a resulting spiraling risk of falls, fear of falling, and functional decline. Because falls and fear of falling share predictors, individuals who are at a high risk of developing these endpoints can be identified. 相似文献
993.
BACKGROUND: It has recently been reported that simultaneous multisite atrial pacing, Bachmann's bundle (BB) pacing, and coronary sinus (CS) pacing are useful for preventing the induction of atrial fibrillation (AF). HYPOTHESIS: We investigated whether a simple pacing approach via BB could reduce the induction of AF by extrastimuli (S2) from the right atrial appendage (RAA). METHODS: Programmed electrical stimulation was performed from the RAA and the area of BB at the superior aspect of the atrial septum, and bipolar recordings were obtained from the RAA, BB, and CS in 14 patients. RESULTS: In five patients, AF was induced with critically timed RAA-S2 delivered during RAA pacing. However, AF was not induced in any patient when RAA-S2 was delivered during BB pacing. The duration of the P wave during BB pacing was significantly shorter than that during RAA pacing and sinus rhythm (BB 80 +/- 16 ms vs. RAA 106 +/- 36 ms vs. sinus rhythm 100 +/- 24 ms, p < 0.05). The intra-atrial conduction time to the distal coronary sinus (CSd) caused by early S2 at the RAA was significantly reduced by BB pacing (BB 114 +/- 22 ms vs. RAA 157 +/- 35 ms, p < 0.001). CONCLUSION: Bachmann's bundle pacing reduces atrial conduction time caused by RAA-S2 and may be useful for preventing the induction of AF. 相似文献
994.
995.
William W. Darrow Robert D. Webster Steven P. Kurtz Abraham K. Buckley Kesuri I. Patel Robert R. Stempel 《AIDS and behavior》1998,2(2):115-126
The impact of HIV counseling and testing on sexual risk-taking and related behaviors reported by HIV-infected men who have sex with men (MSM) was examined in a cross-sectional study conducted among a representative sample of residents living in a resort area. Participants provided specimens of oral mucosal transudate for HIV-antibody testing, were interviewed in their homes, and completed a self-administered questionnaire. Specimens were tested by modified ELISA and, if repeatedly positive, confirmed by Western blot. Of 205 men enrolled, 51 (24.9%) tested positive for antibody to HIV. All 51 had been counseled and tested for antibody to HIV-1 (median = 4 tests); 37 (74%) of 50 reported that their most recent test was positive. Twenty (39.2%) said they had engaged in unprotected insertive anal intercourse in the past year; 15 (29.4%) engaged in unprotected insertive anal intercourse with partners who may have been susceptible to HIV infection. Men who reported that their last HIV-antibody test was positive were three times more likely to have engaged in unprotected insertive anal intercourse in the past year (45.9%) as those who did not know they were infected with HIV (15.4%). Counseling and testing is ineffective as a measure for promoting behavior change among HIV-positive MSM in South Beach. More effective social and behavioral interventions must be developed, implemented, and evaluated. 相似文献
996.
We studied two cases with leukemia that relapsed in the central nervous system (CNS) after allogeneic stem cell transplantation. One patient underwent peripheral blood stem cell transplantation (SCT) from a related, yet haplotype-mismatched, donor for chronic myelomonocytic leukemia. She was kept in complete remission (CR) in the bone marrow (BM) for 7 months, until relapse in the cerebrospinal fluid (CSF) was evident. In the other patient, with acute lymphoblastic leukemia, systemic relapse occurred when he was still on immunosuppression 6 months after SCT from an unrelated donor. After induction chemotherapy following cessation of immunosuppression, the BM examination proved CR. During consolidation chemotherapy, however, he developed leukemic dissemination in the CSF, despite the fact that the BM was in CR. Chimerism status in the BM mononuclear cells and fractionated peripheral blood (PB) cells (granulocytes, T-lymphocytes, and the others) was assessed by short tandem repeat analysis. In both patients, the BM cells and all the fractions of the PB cells proved donor-type chimeras. These results seem to suggest that the graft-versus-leukemia effects might not be as effective in the CNS as in the BM, even when complete T-lymphoid chimerism is achieved. 相似文献
997.
Thiago S. Torres Paula M. Luz Raquel B. De Boni Mauricio T. L. de Vasconcellos Brenda Hoagland Alex Garner 《AIDS care》2019,31(10):1193-1202
ABSTRACTBrazil has the largest population of individuals living with HIV/AIDS in Latin America with a disproportional prevalence of infection among men who have sex with men (MSM). This study evaluated PrEP awareness by age (18–24, 25–35, ≥36 years), its associated factors and the willingness to use HIV prevention technologies among MSM using a GSN app in Brazil. Inclusion criteria were ≥18 years-old, cisgender men and HIV-negative serostatus. Of 7242 individuals, 4136 (57%) completed the questionnaire. PrEP awareness was reported by 51% (though lower among MSM aged 18–24 and ≥36 years) and its associated factors were higher family income, most friends with the same sexual orientation, high number of male sexual partners and marijuana use. HIV testing (never vs. at least once) lead to an almost 3-fold increase in the odds of PrEP awareness. High HIV risk perception led to increased PrEP awareness only among MSM aged 18–24 years. A total of 2335 (56%) was willing to use daily oral PrEP. PrEP awareness remains low in Brazil and mobile tools are key strategies to reach MSM and increase awareness of prevention technologies. Community-based interventions could add to online campaigns to reach the most vulnerable, which include young, non-white and lower-income MSM. 相似文献
998.
The objective of this analysis was to assess the effect of introducing the diaphragm on condom use patterns. Participants
included One hundred eighty nine women attending family planning clinics in Harare, Zimbabwe who reported less than 100% condom
use. The proportion of acts where at least one method was used significantly increased over using follow-up; male condom use
remained stable. A diaphragm was used with 50% to 54% of acts; male condoms were also used about 50% of the time. The proportion
of acts where a female condom was used decreased. Women who used both male and female condoms were more likely to use diaphragms
than those who reported not using female condoms. Introducing the diaphragm increased the overall proportion of protected
acts. The proportion of acts where a male condom was used did not change. Female condoms use declined because concurrent use
with the diaphragm is not possible. 相似文献
999.
Compliance and adverse event withdrawal: their impact on the West of Scotland Coronary Prevention Study 总被引:4,自引:1,他引:4
AIMS: To assess the additional benefit gained from high compliancein the West of Scotland Coronary Prevention Study and to examinecases where withdrawal from trial medication was due to an adverseevent. METHODS: The incidence of definite coronary heart disease or non-fatalmyocardial infarction, cardiovascular mortality, definite orsuspect coronary heart disease death or non-fatal myocardialinfarction, the need for coronary revascularization procedures,all-cause mortality and incident cancers were measured in theentire cohort and compared with the high compliance group. Theadverse events associated with withdrawal were coded by bodysystem. RESULTS: In subjects with compliance 75%, treatment with pravastatinresulted in a 38% risk reduction for definite coronary heartdisease death or non-fatal myocardial infarction and for cardiovascularmortality, a 46% reduction in risk or coronary revascularizationand a 32% risk reduction (P=0·015) for all-cause mortality. CONCLUSION: The analysis of the effect of pravastatin in the subgroup ofhigh compliers to randomized medication demonstrated a substantialincrease in the estimated risk reductions in comparison withthat achieved in the intention-to-treat analysis. This resulthas significant implications for the motivation of high complianceamong patients and for the assessment of the cost-effectivenessof treatment. 相似文献
1000.
目的 研究郑州市城区肺结核病人的发现和管理的发现和管理。方法 对 1996— 2 0 0
2年郑州市综合医院转诊情况及初治涂阳患者治疗转归情况进行队列分析。结果 结核病控制项目实施后初治涂阳病人治愈率显著提高 (87.4 % ) ,丢失率明显下降(0 .6 % ) ,综合医院转诊病人到位率低 ,平均为 32 .5 %。结论 加强行政干预 ,健全城市防痨网络 ,严格推行DOTS策略,是郑州市城区提高肺结核病人管理水平的基础。 相似文献