全文获取类型
收费全文 | 346530篇 |
免费 | 31335篇 |
国内免费 | 24682篇 |
专业分类
耳鼻咽喉 | 3225篇 |
儿科学 | 3670篇 |
妇产科学 | 5123篇 |
基础医学 | 42046篇 |
口腔科学 | 5839篇 |
临床医学 | 47995篇 |
内科学 | 52383篇 |
皮肤病学 | 3318篇 |
神经病学 | 19547篇 |
特种医学 | 12894篇 |
外国民族医学 | 220篇 |
外科学 | 35425篇 |
综合类 | 55044篇 |
现状与发展 | 82篇 |
一般理论 | 21篇 |
预防医学 | 21554篇 |
眼科学 | 10053篇 |
药学 | 35446篇 |
351篇 | |
中国医学 | 18944篇 |
肿瘤学 | 29367篇 |
出版年
2024年 | 1089篇 |
2023年 | 5345篇 |
2022年 | 13938篇 |
2021年 | 17449篇 |
2020年 | 12846篇 |
2019年 | 11565篇 |
2018年 | 12104篇 |
2017年 | 10622篇 |
2016年 | 9952篇 |
2015年 | 15293篇 |
2014年 | 19065篇 |
2013年 | 16626篇 |
2012年 | 24546篇 |
2011年 | 27696篇 |
2010年 | 17398篇 |
2009年 | 13474篇 |
2008年 | 18365篇 |
2007年 | 18413篇 |
2006年 | 18378篇 |
2005年 | 17896篇 |
2004年 | 11550篇 |
2003年 | 10780篇 |
2002年 | 9250篇 |
2001年 | 8116篇 |
2000年 | 8846篇 |
1999年 | 9405篇 |
1998年 | 5722篇 |
1997年 | 5687篇 |
1996年 | 4460篇 |
1995年 | 4039篇 |
1994年 | 3322篇 |
1993年 | 2168篇 |
1992年 | 2878篇 |
1991年 | 2475篇 |
1990年 | 2162篇 |
1989年 | 1903篇 |
1988年 | 1599篇 |
1987年 | 1373篇 |
1986年 | 1128篇 |
1985年 | 927篇 |
1984年 | 541篇 |
1983年 | 376篇 |
1982年 | 243篇 |
1981年 | 240篇 |
1980年 | 188篇 |
1979年 | 221篇 |
1978年 | 82篇 |
1977年 | 89篇 |
1974年 | 102篇 |
1973年 | 83篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
103.
Antiproliferative Activity Against MCF‐7 Breast Cancer Cells by Diamino‐Triazaspirodiene Antifolates
Xiang Ma Renee Ser‐Peng Woon Paul Chi‐Lui Ho Wai‐Keung Chui 《Chemical biology & drug design》2009,74(3):322-326
Two triazaspirodienes, having similar phenoxy propyloxy side chain, were identified as potent mammalian dihydrofolate reductase inhibitors; one having a 6,5‐spiro bicyclic ring system (IC50 = 2.3 nm ) and the other a 6,6‐spiro bicyclic system (IC50 = 6.9 nm ). They also showed more than 50% antiproliferative activity against the MCF‐7 breast cancer cells at 20 μm . This study demonstrated the potential lead of the diamino‐triazaspirodienes in anticancer chemotherapeutical agents’ discovery. 相似文献
104.
提壶揭盖法治疗前列腺增生症82例 总被引:5,自引:0,他引:5
笔者自1995年以来,宗提壶揭盖法,用补中益气汤加减治疗前列腺增生82例疗效满意,报告如下。 相似文献
105.
我院护士工作评估体系及其应用 总被引:4,自引:0,他引:4
目的应用护士工作评估体系,激励护士不断自我完善.方法以自我评估、面对面交流、同事间评估、设立目标和建立护士档案为主要内容的评估.一般为每年1次.结果每年护士评估的覆盖率为100%.提供了上下级面对面交流的机会,每名护士都熟悉评估的程序并自觉参与.结论护士评估体系是护理管理的重要组成部分,它使管理者有机会关注到每名护士的成长需要及成长目标,指导我们能动地利用人力--这一最宝贵的资源. 相似文献
106.
107.
108.
OBJECTIVE: To study the cellular expression of CD45RO, CD20, CD68 and proliferating cell nuclear antigen (PCNA) in nasal polyps. METHODS: Nasal polyp tissues from 50 patients were evaluated for cellular expression of CD45RO, CD20, CD68 and PCNA using immunohistochemistry SP by counting the average number in 5 chosen high-power fields, Histopathological observations were combined with HE. Analyses were performed on SPSS10.0. RESULTS: CD68+ cells were expressed more in nasal polyps dominated by eosinophils than by neutrophils(P < 0.05). There was no difference between CD45RO and CD20, but both of them had negative correlation(P = 0.05). Significant correlation was found between CD68+ cells and eosinophils or PCNA positive cells on epithelium. PCNA positive cells on epithelium had significant correlation on fibroblast (P < 0.05). CONCLUSION: Inflammatory cell infiltration (eosinophilia CD45RO, CD20, CD68) and cell proliferating in epithelium cells, glandular cell and fibroblast are strongly correlated with formation of nasal polyps. The nasal polyps are not only characteristic of eosinophilia but also by lymphocytes dominated by CD45RO and CD68 positive cells. CD68 may be stem cell of nasal polyp. 相似文献
109.
OBJECTIVE: To investigate the clinicopathlogical significance of cyclinE, cyclinD1, P21WAF1/CIP1 and P27KIP1 expression in squamous cell carcinoma of maxillary sinus. METHODS: The expression of cyclinE, cyclinD1, P21WAF1/CIP1 and P27KIP1 was examined by the method of immunohistochemistry in inflammatory mucosa of maxillary sinus(10), inverting papilloma of maxillary sinus(20) and squamous cell carcinoma of maxillary sinus (50). RESULTS: (1) In inflammatory mucosa, inverting papilloma and squamous cell carcinoma, the positive immunostaining rates of cyclinD1 protein were 10.0%, 25.0%, 48.0% respectively (P < 0.05); cyclinE protein was 20.0%, 35.0%, 58.0% respectively (P < 0.05); P21WAF1/CIP1 protein was 80.0%, 65.0%, 40.0% respectively (P < 0.05) and P27KIP1 protein was 70.0%, 75.0%, 40.0% respectively (P < 0.05). (2) There was no significance between the clinical type, T stage and clinical stage of carcinoma of maxillary sinus and the expression of cyclinD1, cyclinE, P21WAF1/CIP1 and P27KIP1 (P > 0.05). (3) P21WAF1/CIP1 positive expression in highly, moderately and poorly differtiated carcinomas were 73.2% (11/15), 58.9% (11/19), 25.0% (4/16) respectively (P < 0.05). CONCLUSION: (1) With the development of the lesion, the positive immunostaining rate of cyclinE and cyclinD1 protein increases, while the rate of P21WAF1/CIP1 and P27KIP1 protein decreases. (2) P21WAF1/CIP1 expression is associated with tumour cell differentiation. (3) The mutual mechenism of cell cycle regulators plays an important role in the squamous cell carcinoma of maxillary sinus. The quantity and the frequency of four kinds of gene expression increase with the progression of maxillary sinus carcinogenesis. 相似文献
110.