全文获取类型
收费全文 | 80222篇 |
免费 | 7813篇 |
国内免费 | 5357篇 |
专业分类
耳鼻咽喉 | 575篇 |
儿科学 | 1087篇 |
妇产科学 | 948篇 |
基础医学 | 8160篇 |
口腔科学 | 1428篇 |
临床医学 | 11488篇 |
内科学 | 10703篇 |
皮肤病学 | 796篇 |
神经病学 | 3607篇 |
特种医学 | 2512篇 |
外国民族医学 | 40篇 |
外科学 | 6028篇 |
综合类 | 15910篇 |
现状与发展 | 23篇 |
一般理论 | 7篇 |
预防医学 | 6689篇 |
眼科学 | 2367篇 |
药学 | 9256篇 |
84篇 | |
中国医学 | 5689篇 |
肿瘤学 | 5995篇 |
出版年
2024年 | 291篇 |
2023年 | 1192篇 |
2022年 | 2929篇 |
2021年 | 3758篇 |
2020年 | 3070篇 |
2019年 | 2496篇 |
2018年 | 2443篇 |
2017年 | 2653篇 |
2016年 | 2263篇 |
2015年 | 3606篇 |
2014年 | 4489篇 |
2013年 | 4408篇 |
2012年 | 6410篇 |
2011年 | 6856篇 |
2010年 | 4994篇 |
2009年 | 4154篇 |
2008年 | 4785篇 |
2007年 | 4680篇 |
2006年 | 4563篇 |
2005年 | 4368篇 |
2004年 | 2803篇 |
2003年 | 2517篇 |
2002年 | 2220篇 |
2001年 | 1748篇 |
2000年 | 1590篇 |
1999年 | 1415篇 |
1998年 | 908篇 |
1997年 | 856篇 |
1996年 | 662篇 |
1995年 | 629篇 |
1994年 | 522篇 |
1993年 | 326篇 |
1992年 | 406篇 |
1991年 | 383篇 |
1990年 | 333篇 |
1989年 | 278篇 |
1988年 | 254篇 |
1987年 | 231篇 |
1986年 | 201篇 |
1985年 | 145篇 |
1984年 | 88篇 |
1983年 | 78篇 |
1982年 | 40篇 |
1981年 | 49篇 |
1980年 | 43篇 |
1979年 | 33篇 |
1978年 | 25篇 |
1973年 | 29篇 |
1972年 | 23篇 |
1970年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
Ko JM Yau WL Chan PL Lung HL Yang L Lo PH Tang JC Srivastava G Stanbridge EJ Lung ML 《Genes, chromosomes & cancer》2005,43(3):284-293
Despite the abundant evidence of high allelic loss of chromosome arm 14q in human cancers, tumor-suppressor genes mapped to this chromosome have yet to be identified. To narrow the search for candidate genes, we performed monochromosome transfer of chromosome 14 into an esophageal carcinoma cell line, SLMT-1 S1. Statistically significant suppression of the tumorigenic potential of microcell hybrids containing the transferred chromosome 14 provided functional evidence that tumor-suppressive regions of chromosome 14 are essential for esophageal cancer. Tumor segregants emerging in nude mice during the tumorigenicity assay were analyzed by detailed PCR-microsatellite typing to identify critical nonrandomly eliminated regions (CRs). A 680-kb CR mapped to 14q32.13 and an approximately 2.2-Mb CR mapped to 14q32.33 were delineated. Dual-color BAC FISH analysis of microcell hybrids and tumor segregants verified the selective loss of the 14q32.13 region. In contrast, similar transfers of an intact chromosome 11 into SLMT-1 S1 did not significantly suppress tumor formation. These functional complementation studies showing the correlation of tumorigenic potential with critical regions of chromosome 14 validated the importance of the 14q32 region in tumor suppression in esophageal cancer. The present study also paved the path for further identification of novel tumor-suppressor genes that are relevant to the molecular pathogenesis of esophageal cancer. 相似文献
102.
Mitochondrial DNA and Y-Chromosome Variation in the Caucasus 总被引:7,自引:3,他引:7
I. Nasidze E. Y. S. Ling D. Quinque I. Dupanloup R. Cordaux S. Rychkov O. Naumova O. Zhukova N. Sarraf-Zadegan G. A. Naderi S. Asgary S. Sardas D. D. Farhud T. Sarkisian C. Asadov A. Kerimov M. Stoneking 《Annals of human genetics》2004,68(3):205-221
We have analyzed mtDNA HVI sequences and Y chromosome haplogroups based on 11 binary markers in 371 individuals, from 11 populations in the Caucasus and the neighbouring countries of Turkey and Iran. Y chromosome haplogroup diversity in the Caucasus was almost as high as in Central Asia and the Near East, and significantly higher than in Europe. More than 27% of the variance in Y‐haplogroups can be attributed to differences between populations, whereas mtDNA showed much lower heterogeneity between populations (less then 5%), suggesting a strong influence of patrilocal social structure. Several groups from the highland region of the Caucasus exhibited low diversity and high differentiation for either or both genetic systems, reflecting enhanced genetic drift in these small, isolated populations. Overall, the Caucasus groups showed greater similarity with West Asian than with European groups for both genetic systems, although this similarity was much more pronounced for the Y chromosome than for mtDNA, suggesting that male‐mediated migrations from West Asia have influenced the genetic structure of Caucasus populations. 相似文献
103.
STUDY OBJECTIVES: Very few studies have evaluated narcolepsy in Asian countries, outside of Japan. Our goal was to study narcolepsy at the genetic, clinical and pathophysiological level in Korea. DESIGN: Prospective study of consecutive patients and age matched controls. Clinical data ascertained from the Stanford Sleep Inventory, Polysomnography and MSLT data, as well as clinical notes. High resolution DRB1 and DQB1 typing in all subjects and studies of CSF hypocretin-1 was also evaluated in a subset of patients. PARTICIPANTS AND SETTING: 20 patients diagnosed at St. Vincent and Korea University Hospitals (Seoul, Korea). 21 Korean control subjects. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: For narcoleptic subjects, mean age was 28.2 years old and 45% were female. Mean BMI was 23.9+/-3.4 kg/m2, a significantly higher value than that expected in an age- and sex-matched sample (p<0.01). All patients had sleepiness and cataplexy while the prevalence of other symptoms ranged from 60-75%. All but 2 subjects were HLA-DR15 (DR2), DQB1*0602 positive (90%). This high DQB1*0602 percentage compared with 24% DQB1*0602 positivity in 21 control Koreans. Protective effects were observed for the DQB1*0601 and DRB1*0406 alleles, Hypocretin (orexin) CSF studies were also performed in 6 cataplectic subjects, all of which had undetectable CSF hypocretin levels. Two of these subjects had started narcolepsy less than 1 year before analysis yet had undetectable hypocretin levels. CONCLUSION: These results illustrate the similarity of narcolepsy-cataplexy in Korea in comparisons with other more studied populations. We also identified a new potential HLA protective subtype, HLA-DRB1*0406. 相似文献
104.
Quality of Life Research - To evaluate and compare the test–retest reliability of discrete choice experiments with duration (DCETTO) and time trade-off (TTO) in the Chinese SF-6Dv2 valuation... 相似文献
105.
106.
结节病患者肺功能变化研究 总被引:2,自引:0,他引:2
目的:肺结节病患者肺功能测试的研究。方法:40例肺结节病患者不同时期肺功能测试结果和应用激素的回顾分析。结果:显示此类患者有限性通气功能障碍并伴有弥散功能下降和小气道功能受限,PaO2明显下降,pH升高,PaCO2也有下降的趋势。激素治疗结果显示,患者的MMF有明显的提高。其它肺功能指标如VC,RV,RV/TLC,MVV,FEV1,DLCO等都有升高的趋势。结论:VC,RV,MMF,DLCO,DLCO/VA等对诊断结节病的病情发展有直接参考价值,而MMF在糖皮质激素治疗后有显著的变化,提高MMF对结节病的治疗和预后具有动态参考价值。 相似文献
107.
护理人员应付方式的相关因素分析 总被引:9,自引:0,他引:9
目的 探讨影响护理人员应付方式的相关因素。方法 采用应付方式问卷和艾森克个性问卷对303名护理人员进行评定。结果 护理人员的应付方式与个性心理特征相关性较大,与年龄和护龄不呈线性关系,与是否倒班和不同的科室无关。4-5年和6-8年护龄的护理人员在应用解决问题应付方式上,比其他护龄组明显减少。结论 应加强护理人员,尤其是工作4-8年的护理人员的应付方式的指导。 相似文献
108.
109.
110.
Clinical significance and assessment of cytokines in various stages of ulcerative colitis 总被引:2,自引:0,他引:2
Summary In order to study the clinical significance and change of interleukin (IL)-1β and IL-10 concentration in intestinal mucosal
tissues in various stage of ulcerative colitis (UC), IL-1β and IL10 levels were measured by enzyme linked immunosorbent assays
(ELISA). Our results showed that IL-β level caused by spontaneous secretion in the intestinal mucous tissues in active stage
of ulcerative colitis was significantly higher than that in normal controls and in remission stage of ulcerative colitis (P <0. 01,P<0. 001). IL-10 level in various stage of UC was relatively lower in controls, but there was no significantly difference between
the two groups. Our study suggested that higher IL-1β level in active might play an important role in pathogenesis of UC,
and IL-10, as an anti-inflammatory cytokine, was low in active UC, suggesting that it may be a important factor contributing
to the development of higher IL-1β level.
This project was supported by the grant of the Scientific Research Fund of the Ministry of Health (No. 98-2-387). 相似文献