全文获取类型
收费全文 | 2574441篇 |
免费 | 189366篇 |
国内免费 | 6594篇 |
专业分类
耳鼻咽喉 | 36689篇 |
儿科学 | 80143篇 |
妇产科学 | 73040篇 |
基础医学 | 363573篇 |
口腔科学 | 73636篇 |
临床医学 | 225706篇 |
内科学 | 505127篇 |
皮肤病学 | 60332篇 |
神经病学 | 209378篇 |
特种医学 | 101787篇 |
外国民族医学 | 879篇 |
外科学 | 388619篇 |
综合类 | 58080篇 |
现状与发展 | 11篇 |
一般理论 | 888篇 |
预防医学 | 190024篇 |
眼科学 | 60431篇 |
药学 | 189751篇 |
5篇 | |
中国医学 | 6731篇 |
肿瘤学 | 145571篇 |
出版年
2021年 | 20455篇 |
2018年 | 28403篇 |
2017年 | 22096篇 |
2016年 | 25420篇 |
2015年 | 29575篇 |
2014年 | 40624篇 |
2013年 | 59235篇 |
2012年 | 80089篇 |
2011年 | 83850篇 |
2010年 | 49484篇 |
2009年 | 47070篇 |
2008年 | 76471篇 |
2007年 | 81118篇 |
2006年 | 81382篇 |
2005年 | 78791篇 |
2004年 | 75272篇 |
2003年 | 71906篇 |
2002年 | 69826篇 |
2001年 | 120144篇 |
2000年 | 123083篇 |
1999年 | 103407篇 |
1998年 | 29054篇 |
1997年 | 26273篇 |
1996年 | 25702篇 |
1995年 | 24343篇 |
1994年 | 22403篇 |
1993年 | 20894篇 |
1992年 | 79000篇 |
1991年 | 75910篇 |
1990年 | 73674篇 |
1989年 | 71112篇 |
1988年 | 65821篇 |
1987年 | 64443篇 |
1986年 | 61271篇 |
1985年 | 58172篇 |
1984年 | 44097篇 |
1983年 | 37295篇 |
1982年 | 22635篇 |
1979年 | 40651篇 |
1978年 | 28874篇 |
1977年 | 24633篇 |
1976年 | 22632篇 |
1975年 | 24726篇 |
1974年 | 29357篇 |
1973年 | 28577篇 |
1972年 | 27113篇 |
1971年 | 24948篇 |
1970年 | 23789篇 |
1969年 | 22560篇 |
1968年 | 21291篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
This paper gives an overview of the changes in the sector of accident insurance companies over recent months and a prognosis for the changes that can still be expected, especially with reference to the election results. 相似文献
102.
Elizabeth C Frenzel Georgia A Thomas Hend A Hanna 《Infection control and hospital epidemiology》2006,27(5):512-514
At the time of hire, 4059 of 6522 healthcare workers required a 2-step tuberculin skin test; 114 workers (2.8%) demonstrated a boosted reaction after the second step. Boosted reactions were significantly associated with male sex and older age. A verbal history of previous tuberculin skin test results was not a reliable indicator of baseline tuberculin skin test status at the time of hire. 相似文献
103.
Michiel R. de Boer Jos Twisk Annette C. Moll Hennie J. M. Völker-Dieben Henrica C. W. de Vet Ger H. M. B. van Rens 《Ophthalmic & physiological optics》2006,26(6):535-544
Consecutive patients (n = 215) who were referred to optometric (55%) or multidisciplinary (45%) low-vision services and above 50 years of age were recruited from four hospitals in the Netherlands. They completed two vision-related quality of life questionnaires, the Vision Quality of Life Core Measure (VCM1) and the Low Vision Quality of Life Questionnaire (LVQOL), before their first visit with low-vision services and 1 year later. At follow-up, patients referred to multidisciplinary low-vision services had lower scores on the mobility subscale of the LVQOL than patients referred to optometric low-vision services [5.3 points; 95% confidence interval (CI): 0.2-10.5]. Paired sample t-tests for the two groups of patients taken together show improvement for the VCM1 (3.1 points; 95% CI: 0.6-5.6) and deterioration for the basic aspects of vision (3.5 points; 95% CI: 1.1-5.9) and the mobility (6.6 points; 95% CI: 3.7-9.5) subscales of the LVQOL. In conclusion, people referred to optometric services showed less deterioration in mobility than those referred to multidisciplinary services. No differences were observed for any of the other subscales of the LVQOL and the VCM1. Future research in this field should include randomized controlled designs comparing low-vision services with no treatment or placebo. 相似文献
104.
C. O. Onyeaso BDS FWACS M. O. Arowojolu BDS FWACS J. O. Taiwo BDS MSc DDPH RCS Eng 《American journal of orthodontics and dentofacial orthopedics》2003,124(6):714-720
This prospective clinic-based study evaluated the pretreatment periodontal status of the orthodontic patients seen at the University College Hospital, Ibadan, Nigeria, and assessed the relationship between dental aesthetic index (DAI) scores and periodontal status according to community periodontal index of treatment needs (CPITN) scores. One hundred forty five patients-70 (48.3%) males and 75 (51.7%) females from 6 to 45 years (mean 15.8 +/- 7.5)-were seen. World Health Organization (WHO) guidelines were followed in the examination and reporting of the periodontal status, and DAI scores were assessed based on WHO guidelines. The chi-square test was used to determine the association between the DAI and the CPITN scores. Most patients were in the 6-15 (55.9%) or 16-25 (35.9%) age groups. Based on the WHO preferred cumulative calculations of treatment need (TN), 35.2% of the patients had TN 0, 64.9% had TN 1, 24.9% had TN 2, and only 0.7% had TN 3. The relationship between DAI scores and periodontal treatment needs was not statistically significant (P >.05). Although many patients were yet to attain the WHO goal of no more than 1 sextant affected by bleeding or calculus at the age of 15, over one third had satisfactory periodontal health. 相似文献
105.
Four clinical trials of porcine islet transplantation have been reported, and there are verbal reports that clinical trials on much larger scales are continuing in centers in China and Russia. The four reported trials are briefly reviewed and, in the light of the present status of experimental islet xenotransplantation, consideration is given to whether such trials are currently justified. The Ethics Committee of the International Xenotransplantation Association has (1) emphasized the need for encouraging studies in non-human primates before clinical trials should be undertaken, (2) mandatory monitoring for the transfer of porcine microorganisms, and (3) careful regulation and oversight by recognized bodies. Other aspects of the topic, such as the need for informed consent, are briefly discussed. We conclude that, at the present time, more data documenting convincing efficacy, focused on clinically applicable immunosuppressive regimens, are needed to justify the initiation of closely monitored clinical trials. A clinical trial may then be justified even though the potential risk to the patients, and possibly for society, will not be zero. 相似文献
106.
Marcondes C Fran?a Maria E Calcagnotto Jaderson C da Costa Iscia Lopes-Cendes 《Movement disorders》2006,21(7):1051-1053
Spinocerebellar ataxia (SCA) types 2 and 3 are autosomal-dominant neurodegenerative disorders caused by mutations in two different genes. We identified mutations for SCA2 and SCA3 segregating simultaneously in a single Brazilian family. The index patient had SCA2, whereas her two second-degree cousins had SCA3. Disease was more rapidly progressive in the SCA2 patient, who presented severe brainstem and pancerebellar atrophy, as opposed to the two SCA3 patients, who had only mild cerebellar vermian atrophy. In such situations, molecular confirmation of all patients may avoid misdiagnosis of SCA subtypes and eventual errors in predictive testing of unaffected family members. 相似文献
107.
108.
109.
110.
H Ishihara M Bjeljac D Straumann Y Kaku P Roth Y Yonekawa 《Minimally invasive neurosurgery》2006,49(3):168-172
OBJECTIVE: A safe entry zone to tegmental lesions was identified based on intraoperative electrophysiological findings, the compound muscle action potentials (CMAP) from the extraocular muscles, and anatomic considerations. This entry zone is bordered caudally by the intramesencephalic path of the trochlear, laterally by the spinothalamic tract, and rostrally by the caudal margin of the brachium of the superior colliculus. METHODS: Four intrinsic midbrain lesions were operated upon via the safe entry zone using the infratentorial paramedian supracerebellar approach. All lesions involved the tegmentum and included an anaplastic astrocytoma, a metastatic brain tumor, a radiation necrosis, and a cavernous angioma. CMAP were bilaterally monitored from the inferior recti (for oculomotor function) and superior oblique (for trochlear nerve function) muscles. RESULTS: In three of four cases, CMAP related to the oculomotor nerve were obtained upon stimulation at the cavity wall after removal of the tumor. Stimulation at the surface of the quadrigeminal plate, however, did not cause any CMAP response. Using this monitoring as an indicator, the lesions were totally removed. CONCLUSIONS: In the surgery of tegmental lesions, CMAP monitoring from extraocular muscles is particularly helpful to prevent damage to crucial neural structures during removal of intrinsic lesions, but less so to select the site of the medullary incision. The approach via the lateral part of the colliculi is considered to be a safe route to approach the tegmental lesions. 相似文献