全文获取类型
收费全文 | 152751篇 |
免费 | 48533篇 |
国内免费 | 4946篇 |
专业分类
耳鼻咽喉 | 2843篇 |
儿科学 | 5276篇 |
妇产科学 | 1114篇 |
基础医学 | 22288篇 |
口腔科学 | 6268篇 |
临床医学 | 21108篇 |
内科学 | 31563篇 |
皮肤病学 | 8636篇 |
神经病学 | 15964篇 |
特种医学 | 6110篇 |
外国民族医学 | 7篇 |
外科学 | 20372篇 |
综合类 | 16875篇 |
现状与发展 | 14篇 |
一般理论 | 25篇 |
预防医学 | 10715篇 |
眼科学 | 2636篇 |
药学 | 14413篇 |
81篇 | |
中国医学 | 7977篇 |
肿瘤学 | 11945篇 |
出版年
2024年 | 450篇 |
2023年 | 1282篇 |
2022年 | 3065篇 |
2021年 | 5001篇 |
2020年 | 7736篇 |
2019年 | 12726篇 |
2018年 | 12133篇 |
2017年 | 13741篇 |
2016年 | 14209篇 |
2015年 | 15363篇 |
2014年 | 16010篇 |
2013年 | 17020篇 |
2012年 | 11099篇 |
2011年 | 11324篇 |
2010年 | 14519篇 |
2009年 | 10090篇 |
2008年 | 7341篇 |
2007年 | 5876篇 |
2006年 | 5273篇 |
2005年 | 4303篇 |
2004年 | 3333篇 |
2003年 | 3157篇 |
2002年 | 2743篇 |
2001年 | 2460篇 |
2000年 | 1971篇 |
1999年 | 1048篇 |
1998年 | 435篇 |
1997年 | 403篇 |
1996年 | 337篇 |
1995年 | 272篇 |
1994年 | 249篇 |
1993年 | 161篇 |
1992年 | 160篇 |
1991年 | 170篇 |
1990年 | 137篇 |
1989年 | 119篇 |
1988年 | 85篇 |
1987年 | 86篇 |
1986年 | 77篇 |
1985年 | 56篇 |
1984年 | 26篇 |
1983年 | 15篇 |
1982年 | 19篇 |
1981年 | 23篇 |
1980年 | 19篇 |
1979年 | 16篇 |
1978年 | 6篇 |
1972年 | 6篇 |
1963年 | 5篇 |
1959年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
重组骨形态发生蛋白-2结合软骨下钻孔治疗犬关节软骨全层缺损的实验研究 总被引:3,自引:0,他引:3
目的 研究重组骨形态发生蛋白-2(rhBMP-2)结合软骨下骨钻孔治疗犬关节软骨全层缺损的可行性,为临床应用提供实验依据。方法 依照软骨缺损处理方法的不同将64侧股骨髁随机均分为4组:①结合组:软骨下骨钻孔 胶原海绵吸附rhBMP-2充填软骨缺损;②BMP组:胶原海绵吸附rhBMP-2充填软骨缺损;③钻孔组:单纯软骨下骨钻孔;④对照组:不作处理或单纯用胶原海绵填塞。术后2、4、8、12周取材观察其大体、光镜、透射电镜、免疫组织化学情况。结果 除对照组仅有纤维组织修复外,其余3组均有不同程度的软骨修复,但结合组的修复在组织细胞形态、超微结构、Ⅱ型胶原含量等方面均明显优于其他两组。结论rhBMP-2结合软骨下骨钻孔能有效修复犬膝关节软骨的全层缺损,该技术可行,有望在临床应用。 相似文献
82.
83.
The main goal of the present work was to longitudinally examine consequences of long‐term moderately elevated levels of stress for various health outcomes. To address this issue, data covering 10 years was used from the ongoing Swedish population‐based prospective Betula Study. Based on the ratings on a validated self‐reported stress scale, matched subsamples between 40 and 65 years of age were divided into a high (n = 137) and low (n = 211) stress group. The reported incidence of cardiovascular, diabetes, psychiatric, tumour and musculoskeletal diseases was assessed 5 and 10 years after baseline (baseline = 1993–1995) without contaminating effects of past health history. The incidence of diseases 5 years after baseline assessment showed no differences between the groups. After 10 years, there was a significantly higher incidence of psychiatric diseases, mainly depression in the high‐stress group as well as a significant effect for tumours, although the number of cases was low. Although moderately elevated stress level may have a possible impact on psychiatric diseases especially depression and some tumours, it seems that prolonged moderate stress does not appear to be harmful to other stress‐related diseases. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
84.
老年认知功能障碍与脑结构CT测量的相关性研究 总被引:1,自引:1,他引:0
目的探讨脑萎缩与老年认知功能障碍之间的相关性。方法对开滦集团公司1063名离退休职工进行健康查体,用简易精神状态量表(MMSE)评定认知功能,按分界值将本次研究对象分为认知功能障碍组和认知功能正常组,同时用CT线性测量脑的相关部位以诊断脑萎缩情况,并对各型脑萎缩与认知功能的相关系数及提示老年认知功能障碍的敏感度、特异度、准确度进行分析。结果1063名观察对象中符合入选标准并资料完整者共计511名,其中108名有认知功能障碍,髓质脑萎缩55名、皮质萎缩5名、混合型萎缩30名;认知功能正常者403名,髓质脑萎缩214名、皮质萎缩13名、混合型萎缩62名。认知功能障碍组脑萎缩的发病率高于认知功能正常组,差异具有统计学意义(P<0.005);2组间颞叶海马钩回间距(26.86mm±3.73mmvs25.95mm±3.80mm)及海马钩回间距/大脑左右径的比值(0.21±0.02vs0.20±0.02)差异具有统计学意义(P<0.05);海马钩回间距、皮质脑萎缩、混合型脑萎缩与认知功能障碍呈负相关(分别为r=-0.094,P=0.034,r=-0.156,P≈0.000,r=-0.147,P≈0.000),以海马钩回间距20mm提示老年认知功能障碍的敏感度最高(98.14%),混合型脑萎缩的特异度(84.86%)、准确度最高(72.80%)。结论CT测量相关脑结构,判断脑萎缩类型可以为老年认知功能障碍的诊断提供有价值的信息。 相似文献
85.
86.
Yasushi Nishihira Chun‐Feng Tan Junko Hirato Junichi Yoshimura Kenichi Nishiyama Hideaki Takahashi Yukihiko Fujii Hitoshi Takahashi 《Neuropathology》2007,27(6):551-555
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT. 相似文献
87.
88.
89.
90.
Yasushi Sano Hirohisa Machida Kuang‐I. Fu Hiroaki Ito Takahiro Fujii 《Digestive endoscopy》2004,16(Z1):S93-S96
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms. 相似文献