全文获取类型
收费全文 | 52625篇 |
免费 | 5661篇 |
国内免费 | 4311篇 |
专业分类
耳鼻咽喉 | 446篇 |
儿科学 | 528篇 |
妇产科学 | 523篇 |
基础医学 | 5545篇 |
口腔科学 | 893篇 |
临床医学 | 6385篇 |
内科学 | 6918篇 |
皮肤病学 | 524篇 |
神经病学 | 2398篇 |
特种医学 | 1907篇 |
外国民族医学 | 20篇 |
外科学 | 5174篇 |
综合类 | 11441篇 |
现状与发展 | 10篇 |
一般理论 | 2篇 |
预防医学 | 4476篇 |
眼科学 | 1285篇 |
药学 | 5853篇 |
42篇 | |
中国医学 | 4075篇 |
肿瘤学 | 4152篇 |
出版年
2024年 | 217篇 |
2023年 | 805篇 |
2022年 | 2115篇 |
2021年 | 2614篇 |
2020年 | 2126篇 |
2019年 | 1827篇 |
2018年 | 1795篇 |
2017年 | 1752篇 |
2016年 | 1689篇 |
2015年 | 2521篇 |
2014年 | 2916篇 |
2013年 | 2822篇 |
2012年 | 3574篇 |
2011年 | 3893篇 |
2010年 | 2733篇 |
2009年 | 2112篇 |
2008年 | 2424篇 |
2007年 | 2825篇 |
2006年 | 2650篇 |
2005年 | 2304篇 |
2004年 | 2556篇 |
2003年 | 3133篇 |
2002年 | 2818篇 |
2001年 | 2258篇 |
2000年 | 1455篇 |
1999年 | 1018篇 |
1998年 | 658篇 |
1997年 | 600篇 |
1996年 | 404篇 |
1995年 | 370篇 |
1994年 | 315篇 |
1993年 | 184篇 |
1992年 | 207篇 |
1991年 | 177篇 |
1990年 | 155篇 |
1989年 | 147篇 |
1988年 | 105篇 |
1987年 | 95篇 |
1986年 | 71篇 |
1985年 | 65篇 |
1984年 | 26篇 |
1983年 | 21篇 |
1982年 | 10篇 |
1981年 | 17篇 |
1980年 | 10篇 |
1979年 | 5篇 |
1976年 | 2篇 |
1963年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
目的 探讨Fas及bcl 2在视网膜母细胞瘤的表达及意义。方法 用免疫组织化学SP方法检测了 45例视网膜母细胞瘤及 12例正常视网膜组织中Fas及bcl 2蛋白的表达 ,并进行比较。结果 Fas在视网膜母细胞瘤组织及正常视网膜组织的表达分别为 0 .2 5 5± 0 .441,0 .0 83± 0 .2 89,两者比较差异无显著性 (P =0 .114 8) ,均呈低表达 ;bcl 2在视网膜母细胞瘤中的表达为2 .70 2± 1.0 82 ,与正常视网膜组织中 0 .16 7± 0 .389相比差异具非常显著性 (P <0 .0 0 0 1)。结论 Fas在视网膜母细胞瘤及正常视网膜中均呈低表达 ;而bcl 2在视网膜母细胞瘤中呈明显高表达 ,其可明显抑制凋亡的发生 ,与肿瘤的发展关系密切。 相似文献
92.
卵巢癌患者手术前后IL-2,sIL-2R及mIL-2R水平改变的临床意义 总被引:8,自引:3,他引:5
探讨卵巢癌患的细胞状态以及IL-2血清游离白细胞介素-2受体,外周血单个核细胞膜结构型白细胞介素-2受体与临床的关系。方法^3H-TdR参入法测31例卵巢癌患IL-2产生水平,ELISA法检测血清sIL-2R水平,APAAP免疫组化检测外周血单个核细胞膜结合型IL-2R表达细胞。 相似文献
93.
现代信息技术对高校图书馆的影响与对策 总被引:4,自引:0,他引:4
肖成滨 《山东医科大学学报(社会科学版)》2000,14(1):71-73
现代信息技术的应用为我国高校图书馆事业的发展创造了机遇,同时也向图书馆传统服务方式、馆员队伍提出了挑战。本文论述了面向知识经济与现代信息技术的挑战,高校图书馆建设与发展趋势及应采取的对策。 相似文献
94.
异丙酚氯胺酮混合液静脉麻醉 总被引:3,自引:0,他引:3
选择 40例 ASA ~ 级病人行异丙酚氯胺酮 (1∶ 2 )复合静脉麻醉。结果麻醉诱导后血压、心率与麻醉前相比无明显变化 ,2 0 %病人出现一过性 SPO2 下降 (<94% )。麻醉诱导苏醒快 ,满意率高 ,恢复期无精神症状。表明异丙酚可控制氯胺酮的心血管兴奋作用和恢复期精神症状 ,氯胺酮可减轻异丙酚的心血管抑制作用。两者配伍是一种较好的短效静脉麻醉方式 ,但仍存在呼吸抑制作用 ,应引起注意。 相似文献
95.
Despite a large number of histopathologic and immunohistochemical studies, the biologic behavior and prognosis of paragangliomas (glomus tumors) of the head and neck still remain uncertain. In the present study 36 specimens from 32 patients who underwent surgery for a paraganglioma were examined. The examinations included routine histology, quantitative DNA analysis based on image cytometry, immunohistochemical detection of the proliferating cell nuclear antigen (PCNA) along with visualization of nucleolar organizer regions (AgNOR). According to LeCompte, the paragangliomas were histologically divided into three subcategories: 16 patients had a paragangliomatous tumor. 14 patients had an adenomatous tumor, and 6 patients had an angiomatous tumor. Quantitative DNA analysis revealed three categories of tumors with characteristical DNA pattern; DNA type I tumors were pure diploid, DNA type II tumors had stemlines at 2c and 4c and were therefore recognized as diploid-tetraploid. Aneuploid cells were not apparent in these two groups. DNA type III tumors had stemline ploidies exceeding 2c and 4c. Aneuploid cells were present in all of these tumors. The biologic behavior of these lesions therefore must be recognized as suspicious. DNA type III tumors and adenomatous tumors showed the highest values for the PCNA scores, indicating a higher proliferation rate and a more rapid growth pattern in these lesions. Twenty patients could be followed over a period of up to 110 months. Five of these patients developed a recurrent tumor. All of them had DNA type III tumors. The DNA indices showed significantly higher values in the recurrent tumor group. The 2c deviation index (DI) and the entropy value had the highest prognostic significance. No correlation to clinical follow-up was found for the AgNOR score. Based on these results, prognostic indices for paragangliomas were developed: patients with a tumor having a 2c DI exceeding 2.0, entropy value of more than 4.0. 5c exceeding rate more than 8.0, and a PCNA score more than 20.0% can be recognized as being at high-risk for developing recurrent disease. 相似文献
96.
中国近代西医产科学史 总被引:1,自引:1,他引:0
Xiao W 《Zhonghua yi shi za zhi (Beijing, China : 1980)》1995,25(4):204-210
本文阐述了中国西医产科学的发展历史。由于传统封建思想的阻碍,我国现代产科学的起步较晚,1911年在福建省建立了我国第一所产科病房。1930年以前孕产妇及新生儿死亡率比英美高4~5倍,1930年后,建立助产学校,开展孕期保健及骨盆测量,不断改进对病理妊娠的诊断及妊娠合并症的处理,这些均促进了中国近代西医产科学的进步,也为建国后的发展奠定了基础。 相似文献
97.
Form May to September, 1996, 20 mg/L
lidocaine-uterocervica-injection was performed before operation of induced abortion to
expand uterocervica. By using single blind, the women of 6—12 week pregnancy without
cardiovascular diseases who required to end the pregnancy were selected and randomly
divided into two groups of A and B. 125 cases in group A served as lidocaine-treated group
and 120 cases in group as control group. The results showed that the successful rate,
effective rate and invalid rate in anesthetic effect in group A were 90 %, 6.4 % and 3.2 %
respectively. There was a significant difference in the incidence in induced-abortion
syndrome between the two groups (P<0.01). There was no significant difference in
bleeding volume between the two groups (P>0.05). 相似文献
99.
A terminal transferase-mediated dUTP nick end labeling (TUNEL) method was utilized for detection of neuronal death in the subcortical relay nuclei of the trigeminosensory system following the infraorbital nerve transection in newborn rats. At 18-24 h after injury, numerous TUNEL-positive profiles were found within the ventroposteromedial thalamic nucleus (VPM) contralateral to the injury, whereas the VPM on the ipsilateral side and of the age-matched normal control contained only a few profiles per section. Electron microscopy revealed that the TUNEL-positive profiles were apoptotic neurons. The ventral part of the ipsilateral brainstem sensory trigeminal nuclear complex (the nucleus principalis, and the subnuclei oralis and interpolaris) exhibited statistically significant 65-70% increase in number of apoptotic neurons compared to the contralateral side. Taken together with our previous study [T. Sugimoto, C. Xiao, H. Ichikawa, Neonatal primary neuronal death induced by capsaicin and axotomy involves an apoptotic mechanism, Brain Res. 807 (1998) 147-154], the present results demonstrated a cascade of apoptosis in the primary, secondary and tertiary order sensory neurons along the neuroaxis. 相似文献
100.
The mechanisms by which autoimmune diseases are triggered and by which the activation of autoreactive T cells is initiated and maintained are not yet fully understood. As the most potent antigen presenting cells (APC), and also being responsible for antigen transport as well as primary sensitisation of T cells, dendritic cells (DC) are capable of breaking the state of self-ignorance and inducing aggressive autoreactive T cells. In the development of autoimmune diseases, different types of DC exhibit distinct properties for inducing Th1/Th2 cell responses. Appropriate cytokines can convert immunogenic DC to tolerogenic DC. Utilizing the possibility to promote the tolerogenic effects of DC, a new therapeutic tool might soon become available to treat multiple sclerosis and other autoimmune diseases. 相似文献