全文获取类型
收费全文 | 566699篇 |
免费 | 38596篇 |
国内免费 | 27630篇 |
专业分类
耳鼻咽喉 | 4129篇 |
儿科学 | 11684篇 |
妇产科学 | 7181篇 |
基础医学 | 58554篇 |
口腔科学 | 8030篇 |
临床医学 | 67643篇 |
内科学 | 82237篇 |
皮肤病学 | 4993篇 |
神经病学 | 34869篇 |
特种医学 | 23746篇 |
外国民族医学 | 228篇 |
外科学 | 64709篇 |
综合类 | 78469篇 |
现状与发展 | 91篇 |
一般理论 | 31篇 |
预防医学 | 46826篇 |
眼科学 | 13707篇 |
药学 | 52397篇 |
461篇 | |
中国医学 | 26915篇 |
肿瘤学 | 46025篇 |
出版年
2024年 | 1125篇 |
2023年 | 5214篇 |
2022年 | 13316篇 |
2021年 | 19185篇 |
2020年 | 15070篇 |
2019年 | 12269篇 |
2018年 | 33601篇 |
2017年 | 29012篇 |
2016年 | 30042篇 |
2015年 | 18781篇 |
2014年 | 23154篇 |
2013年 | 21394篇 |
2012年 | 37467篇 |
2011年 | 54817篇 |
2010年 | 41832篇 |
2009年 | 30576篇 |
2008年 | 42435篇 |
2007年 | 44214篇 |
2006年 | 22378篇 |
2005年 | 22812篇 |
2004年 | 17020篇 |
2003年 | 17368篇 |
2002年 | 13120篇 |
2001年 | 9369篇 |
2000年 | 9198篇 |
1999年 | 8829篇 |
1998年 | 5575篇 |
1997年 | 5415篇 |
1996年 | 4167篇 |
1995年 | 3918篇 |
1994年 | 3303篇 |
1993年 | 2125篇 |
1992年 | 2491篇 |
1991年 | 2240篇 |
1990年 | 1935篇 |
1989年 | 1643篇 |
1988年 | 1346篇 |
1987年 | 1185篇 |
1986年 | 972篇 |
1985年 | 708篇 |
1984年 | 388篇 |
1983年 | 293篇 |
1982年 | 169篇 |
1981年 | 171篇 |
1980年 | 154篇 |
1979年 | 157篇 |
1978年 | 81篇 |
1974年 | 61篇 |
1938年 | 62篇 |
1932年 | 61篇 |
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
991.
Heather S. Jim Michael A. Andrykowski Pamela N. Munster Paul B. Jacobsen 《Annals of behavioral medicine》2007,34(2):200-208
Background: Studies suggest that the period following completion of treatment can be distressing for cancer patients. One potentially
important predictor of distress is physical symptoms/side effects during treatment.Purpose: A longitudinal, observational design was used to examine whether the number of physical symptoms/side effects experienced
during treatment was a correlate of cancer-related distress and general distress 4 months after treatment completion, as measured
by the Impact of Events Scale and the Mental Health subscale of the Short Form-36, respectively.Methods: Participants were 151 women who had completed chemotherapy and/or radiotherapy for ductal carcinoma in situ or stage 1 or
2 breast cancer. Hierarchical multiple regression was conducted with relevant sociodemographic, clinical, and psychiatric
variables entered as controls.Results: Greater physical symptoms/side effects predicted greater total cancer-related distress, intrusive thoughts, and general distress.
Physical symptoms/side effects did not significantly predict avoidance. Follow-up analyses indicated that the relationship
between physical symptoms/side effects and general distress was mediated by both total cancer-related distress and intrusive
thoughts.Conclusions: These results suggest that patients who experience greater physical symptoms/side effects during treatment are at greater
risk for later cancer-related distress and, in turn, general distress. Future research should evaluate whether early intervention
with these patients is effective in preventing or reducing distress in the posttreatment period.
This work was supported by a grant from the National Cancer Institute (5R01 CA082822). 相似文献
992.
993.
Mina K. Chung 《Journal of interventional cardiac electrophysiology》2004,10(1):45-53
Recent randomized trials have not demonstrated mortality or stroke risk reduction benefits from a rhythm-control compared to rate-control strategy in the treatment of atrial fibrillation. These studies reinforce the need for continued anticoagulation in both strategies for patients with atrial fibrillation and risk factors for stroke. Although rate control can be rationalized as a first line approach, rhythm control strategies may be justified for patients who are younger, who remain symptomatic or functionally impaired, or who have a first episode of atrial fibrillation. 相似文献
994.
目的 探讨脑梗死后抑郁与负性生活事件的关系。方法 将脑梗死患者按是否受负性生活事件影响分为 A(n=75 )、B(n=73)两组。采用抑郁自评量表 (SDS)及 Hamilton抑郁量表筛查 ,对两组进行比较分析 ,并观察其治疗效果。结果 A、B两组脑梗死后抑郁的发生率分别为 5 6 %、38.4 % ,两者比较差异显著 (P<0 .0 5 ) ;百忧解可显著改善或治愈脑梗死后抑郁 ,总有效率 6 1.7%。结论 脑梗死后抑郁发生与负性生活事件相关。百忧解治疗有效 相似文献
995.
Objective To evaluate the sensitivity and specificity of regularly used immunohistochemical markers, including Vimentin (Vim), Desmin (Des), Myoglobin (MG), Myosin (MS), Smooth-muscle actin (SMA) and Sarcomeric actin ( Sr-A ) , in the diagnosis of rhabdomyosarcoma (RMS). Methods After resection, 24 RMSs and other childhood tumor specimens were fixed in 10% neutral-buffered formalin and embeded in paraffin. The immunohistochemical staining was performed by LSAB procedure. Heat-induced epitope retrieval of Des, MS, Sr-A was processed in order to enhence positive rate and positive strength. Results Vim, MG, MS, Des, Sr-A, SMA were arranged in the order of sensitivity from higher to lower. About specificity, Sr-A, Des, SMA, MG, Vim standed in a sequence from higher to lower ( the data of MS is insufficient) ; Des, MG, Sr-A possessedhigher experimental efficiency, followed by SMA, Vim in a succession. Conclusion Vim and MG are of the higher sensitivity but lower specificity. On the reverse, Sr-A and Des hoM the better specificity but lower sensitivity. So the combination of multiple antibody reactions shouM be considered to improve the diagnostic ability in poorly differentiated RMS. According to the result of experimental efficiency, we suggest that the combination of Des, MG and Sr-A can make it possible to diagnose the majority of RMS clearly. 相似文献
996.
997.
目的 应用Meta分析的方法评价进展期霍奇金病经化疗达完全缓解后巩固放疗的作用。材料和方法 在MEDLINE、CBMdisc数据库检索进展期霍奇金病化疗达完全缓解行巩固性放疗或不行巩固性放疗的前瞻性随机对照研究。对入选研究的总生存、无事件生存优势比进行Meta分析。结果 4项研究入选,以α=0.05为检验水准,巩固性放疗组与对照组(不作巩固性放疗)相比,5年总生存优势比=1.18,P=0.46;5年无事件生存优势比=1.05.P=0.83:巩固性侵犯野放疗组与对照组相比,5年总生存优势比=0.96,P=0.87。结论 进展期霍奇金病经化疗达到完全缓解后,巩固性放疗对总生存及无事件生存均无益处。 相似文献
998.
999.
双波长等吸收紫外分光法测定玻璃体内苏拉明浓度 总被引:2,自引:0,他引:2
[目的]设计并论证检测玻璃体内苏拉明质量浓度的双波长等吸收紫外分光法.[方法]25只白兔摘除眼球冷冻后获取玻璃体,经过匀浆、沉淀、稀释等系列预处理后首先检验正常兔眼玻璃体个体差异性及紫外分光法测定玻璃体内苏拉明浓度的方法学特异性.接着建立标准曲线方程,考察检测方法的精密度和准确度,确立最低检测定量限,最后检测苏拉明在玻璃体内的样品稳定性.[结果]选取261 nm和269 nm两波长,全部6个个体及混合玻璃体的吸光值差△A(A261-A269)介于±0.002之间;外加高、低浓度苏拉明的曲线以及实际注药的高、低浓度苏拉明曲线与空白玻璃体的曲线走势一致且位于其上,各曲线的波峰波谷位置未见偏移;标准曲线方程为y=4 234 x 2,r=0.999 1;次低、中浓度、次高标准浓度点的日内相对标准差(RSD)分别为13.16%、9\67%、10.35%,日间RSD分别为17.59%、10.09%、11.11%,相对回收率分别为:(95.89±0.08)%、(96.69±0.07)%、(97.43±0.01)%;设计标准曲线的最低质量浓度45μg/mL;其日内、日间相对标准差分别为14.14%、15.94%,检验回收率为(94.92±0.01)%;常温组样品,8 h及以内稳定性尚好,之后不稳定.低温组及3次冻融组稳定性良好.[结论]在给定条件下,白兔玻璃体的个体差异可以忽略,双波长等吸收紫外分光法检测玻璃体内苏拉明浓度的方法学特异性好,精确度、准确度、灵敏度和样品稳定性符合规定要求,因此用该方法测定的玻璃体内药物浓度结果可靠. 相似文献
1000.
Involvement of Apoptosis in 3-nitropropionic Acid-induced Ischemicl Tolerance to Transient Focal Cerebral Ischemia in Rats 总被引:3,自引:0,他引:3
Preconditioningofbraintissueswithsub lethalstressesorstimulicanresultinresistancetosubse quentlethalischemiceventsinaresponsecalledis chemictolerance .Recently ,severalstudieshaveshownthatasinglesystemicdoseof 2 0mg/kg 3 NPAcausednohistopathologicalabnorm… 相似文献