全文获取类型
收费全文 | 20147篇 |
免费 | 2498篇 |
国内免费 | 470篇 |
专业分类
耳鼻咽喉 | 243篇 |
儿科学 | 558篇 |
妇产科学 | 176篇 |
基础医学 | 1575篇 |
口腔科学 | 296篇 |
临床医学 | 2061篇 |
内科学 | 1531篇 |
皮肤病学 | 577篇 |
神经病学 | 750篇 |
特种医学 | 2392篇 |
外国民族医学 | 15篇 |
外科学 | 1476篇 |
综合类 | 2284篇 |
现状与发展 | 2篇 |
一般理论 | 10篇 |
预防医学 | 3212篇 |
眼科学 | 245篇 |
药学 | 887篇 |
8篇 | |
中国医学 | 442篇 |
肿瘤学 | 4375篇 |
出版年
2024年 | 34篇 |
2023年 | 325篇 |
2022年 | 411篇 |
2021年 | 894篇 |
2020年 | 776篇 |
2019年 | 778篇 |
2018年 | 784篇 |
2017年 | 794篇 |
2016年 | 900篇 |
2015年 | 957篇 |
2014年 | 1470篇 |
2013年 | 1908篇 |
2012年 | 1309篇 |
2011年 | 1314篇 |
2010年 | 1007篇 |
2009年 | 914篇 |
2008年 | 915篇 |
2007年 | 892篇 |
2006年 | 854篇 |
2005年 | 750篇 |
2004年 | 613篇 |
2003年 | 580篇 |
2002年 | 460篇 |
2001年 | 412篇 |
2000年 | 330篇 |
1999年 | 279篇 |
1998年 | 270篇 |
1997年 | 247篇 |
1996年 | 236篇 |
1995年 | 174篇 |
1994年 | 152篇 |
1993年 | 130篇 |
1992年 | 125篇 |
1991年 | 138篇 |
1990年 | 104篇 |
1989年 | 113篇 |
1988年 | 93篇 |
1987年 | 81篇 |
1986年 | 78篇 |
1985年 | 92篇 |
1984年 | 75篇 |
1983年 | 66篇 |
1982年 | 59篇 |
1981年 | 46篇 |
1980年 | 50篇 |
1979年 | 39篇 |
1978年 | 17篇 |
1977年 | 16篇 |
1976年 | 20篇 |
1968年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Increased heritability for lower IQ levels? 总被引:1,自引:0,他引:1
Dettermanet al. (1990) presented evidence based on twins that the heritability of IQ may be higher in the lower part of the IQ range. We first offer an alternative test for differential heritability across the IQ range, based on the analysis of absolute intrapair differences of monozygotic versus dizygotic twins. We then review two previous studies, each containing more twins than the sample of Dettermanea al., which examined the distribution of intrapair absolute differences. In contrast to the study of Dettermanet al., both yielded results more compatible with higher heritability in the upper range of IQ. We discuss various interpretations of these findings and show how our proposed test might aid in distinguishing among them. 相似文献
72.
吉林省经七年来的鼠情监测,基本查清与人们接触密切的鼠类,特别是传播疾病的主要鼠类的分布规律,分析出我省家鼠有两个高峰(6月和10~11月),野鼠也有两个高峰(6月和10月),这与我省流行性出血热两个高峰相吻合,鼠峰在病峰之前。1986年以后,由于我省开展大规模灭家鼠活动,家鼠高峰已不存在规律性。通过几年来的灭鼠活动,使家鼠密度呈下降趋势,城镇褐家鼠和小家鼠构成比发生变化。城镇未爆发家鼠型流行性出血热。鼠情监测为灭鼠防病工作提供了科学依据。 相似文献
73.
Increased sensitization in urban vs. rural environment – Rural protection or an urban living effect?
Kostas N. Priftis Michael B. Anthracopoulos Alexandra Nikolaou-Papanagiotou Vasiliki Mantziou Athanasios G. Paliatsos George Tzavelas Polyxeni Nicolaidou Eva Mantzouranis 《Pediatric allergy and immunology》2007,18(3):209-216
In a population-based longitudinal cohort study, we tested the hypothesis that children growing up in a high-traffic polluted urban area (UA) in the Athens' basin have higher prevalence of allergies and sensitization when compared with those growing up in a Greek provincial rural area (RA). We recruited 478 and 342 children aged 8-10 living in the UA and the RA, respectively. Respiratory health was assessed by a parent-completed questionnaire in three phases: 1995-96 (phase 1), 1999-2000 (phase 2), 2003-04 (phase 3) and skin-prick testing to common indoor and outdoor aeroallergens was performed at phases 1 and 2. Reported asthma and eczema did not differ between the two areas, whereas reported hay fever was persistently more prevalent in the UA than in the RA (16.5%, 17.0%, 18.2% vs. 7.0%, 8.3%, 9.6%, respectively). Sensitization was more prevalent in the UA at both phases (19.0% vs. 12.1% in phase 1, 20.0% vs. 14.1% in phase 2). Residential area contributed independently to sensitization to >or=1 aeroallergens (OR: 0.29; 95% CI: 0.13-0.66; p = 0.003) and to polysensitization (OR: 0.28; 95% CI: 0.10-0.82; p = 0.020) in phase 1. These associations were independent of farming practices. No significant contributions were found in phase 2. Our results suggest that long-term exposure to urban environment is associated with a higher prevalence of hay fever but not of asthma or eczema. The negative association between rural living and the risk of atopy during childhood, which is independent of farming practices, implies that it is mainly driven by an urban living effect. 相似文献
74.
75.
ISAO HARA SATOKO HIKOSAKA HIROSHI ETO HIDEAKI MIYAKE YUJI YAMADA TOSHINORI SOEJIMA KAZURO SUGIMURA SADAO KAMIDONO 《International journal of urology》2004,11(8):678-682
We report on two cases of women with locally advanced squamous cell carcinoma of the urethra. Patient 1 also displayed regional lymph node metastasis. Treatment comprised combined radiotherapy to 60 Gy and chemotherapy with 5-fluorouracil and cisplatin. Complete response was obtained in both patients, including the inguinal lymph nodes of Patient 1. Patient 1 experienced recurrent inguinal lymph node metastasis on the contralateral side at 42 months after initial treatment, and the same treatment was performed followed by surgical excision. Both patients remain alive with no evidence of disease, at 12 months after recurrence in Patient 1, and at 27 months after treatment in Patient 2. 相似文献
76.
Kemal Yucesoy Iman Feiz-Erfan Robert F. Spetzler Patrick P. Han Stephen Coons 《Skull base》2004,14(3):169-173
A 42-year-old female presented with subarachnoid hemorrhage (SAH), presumably from a radiation-induced anterior communicating artery aneurysm. Six years earlier, she had undergone radiation treatment for an optic glioma that was diagnosed based on imaging criteria. The aneurysm was successfully clipped, and the optic glioma was biopsied to verify the diagnosis histologically. Radiation-induced cerebral aneurysms often manifest with a fatal SAH. These aneurysms typically develop in the field of radiation and are diagnosed a mean of 8.52 years after radiation. Rarely, the aneurysm sac thromboses spontaneously. Clipping or coiling of the aneurysm can be an effective treatment. 相似文献
77.
本文作者密切联系构建和谐社会的理论与实践,科学地探讨了教学过程自身的和谐、教学过程与教学环境的和谐等实践问题。 相似文献
78.
79.
门诊部小黄家蚁防治的探讨 总被引:1,自引:0,他引:1
本文叙述了小黄家蚁危害以及对防治采取的措施,根据效果认为防治小黄家蚁危害首要是综合防制、以治理室内环境为主,辅以化学和物理方法能使小黄家蚁密度降至不足为害的水平。 相似文献
80.
5名电离辐射事故患者外周血T细胞T细胞抗原受体、T细胞分化抗原决定簇-3效应的研究 总被引:1,自引:0,他引:1
文中报道了5名事故性急性骨髓型放射病患者照后2.5和3.5年外周血T淋巴细胞T细胞受体(TCR)基因,TCR、T细胞分化抗原决定簇-3(CD_3)表达与TCR/CD_3复合物功能的辐射效应.发现5名患者于照后2.5年,2名(5.2Gy和2.4Gy,55岁)于照后3.5年外周血T细胞应答抗CD3单抗刺激而增殖的能力尚未完全恢复;经同时用IL-2和抗CD_3单抗刺激,增殖能力比单用抗CD_3单抗刺激有所增强;后2名的外周血TCR、CD_3阳性细胞百分率一直低于正常对照和其他患者;并见一患者出现DNA重排杂交带型.本文并从TCR/CD_3在介导T细胞抗原刺激反应中的作用,电离辐射对TCR/CD_3复合物的影响,后果和意义等方面进行了讨论. 相似文献