首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   87849篇
  免费   7990篇
  国内免费   6520篇
耳鼻咽喉   707篇
儿科学   918篇
妇产科学   1057篇
基础医学   10774篇
口腔科学   1648篇
临床医学   12035篇
内科学   13220篇
皮肤病学   834篇
神经病学   4781篇
特种医学   3204篇
外国民族医学   61篇
外科学   8547篇
综合类   14962篇
现状与发展   30篇
一般理论   3篇
预防医学   5222篇
眼科学   2546篇
药学   9082篇
  68篇
中国医学   4792篇
肿瘤学   7868篇
  2024年   316篇
  2023年   1641篇
  2022年   3843篇
  2021年   4669篇
  2020年   3491篇
  2019年   3052篇
  2018年   3130篇
  2017年   2870篇
  2016年   2611篇
  2015年   4125篇
  2014年   4917篇
  2013年   4183篇
  2012年   6302篇
  2011年   7126篇
  2010年   4270篇
  2009年   3256篇
  2008年   4189篇
  2007年   4483篇
  2006年   4414篇
  2005年   4540篇
  2004年   2785篇
  2003年   2546篇
  2002年   2217篇
  2001年   1904篇
  2000年   2142篇
  1999年   2497篇
  1998年   1663篇
  1997年   1582篇
  1996年   1211篇
  1995年   1057篇
  1994年   885篇
  1993年   603篇
  1992年   713篇
  1991年   609篇
  1990年   551篇
  1989年   474篇
  1988年   392篇
  1987年   349篇
  1986年   247篇
  1985年   190篇
  1984年   92篇
  1983年   76篇
  1982年   41篇
  1981年   45篇
  1980年   29篇
  1979年   30篇
  1965年   1篇
排序方式: 共有10000条查询结果,搜索用时 3 毫秒
11.
Skin penetration of topically applied diclofenac is important for the treatment of rheumatic diseases and actinic keratoses. We have studied the permeation of diclofenac across human cadaver epidermis in-vitro from four lecithin vesicle formulations and a few marketed semi-solid preparations. The lecithin vesicle formulations were prepared by dissolving the lipid contents (lecithin and sodium cholate) in a 1:1 mixture of methanol-chloroform, evaporating the solvents under vacuum, and hydrating the lipid layer with the drug solution in water or 10% ethanol. The vesicles were sonicated for 5 min to reduce the vesicle size and their size and Zeta potential were characterized. The cumulative amount and maximum flux of diclofenac was 69.7+/-40.3 micrograms and 4.77+/-3.16 micrograms/hcm(2) from lecithin vesicles containing sodium cholate and 10% ethanol, and is the highest of all formulations studied. The cumulative amount and mean maximum flux obtained from other formulations were in the range of 2.46+/-1.98-29.9+/-10.1 micrograms and 0.53+/-0.46-3.61+/-0.86 micrograms/hcm(2). Based on the results, lecithin vesicles of diclofenac appear to be advantageous for the topical delivery of diclofenac.  相似文献   
12.
13.
目的:基于累及头颈部淋巴组织病变的临床不典型性,旨在探讨MRI对其进行鉴别诊断的客观依据。方法:对本组22例可疑累及头颈部淋巴组织的各类病变进行MRI检查并与病理学结果进行对照。结果:MRI对本组22例累及淋巴组织病变的诊断与病理学诊断的符合率(21/22)约为95%。结论:MRI是对累及头颈部淋巴组织病变的重要检查手段,并能为明确其诊断提供客观依据。  相似文献   
14.
Mingying  Lai  Ningli  Wang 《眼科学报》1997,13(3):116-119
Purpose : To compare the clinical application value of Ultrasound biomicrsocpic dark room provocative test with the traditional dark room test in screening primary angle closure glaucoma (PACG).Methods: 22 eyes with PACG in prodromal stage and 30 eyes with deep anterior chamber and wide angle of 15 normal persons were observed in this trail. All 52 eyes were performed traditional dark room provocative test and ultrasound biomicorosopic darkroom test respectively. With different positive diagnostic criteria, the sensitivity of the two methods were compared using chi-squared analysis.Results : After staying in the dark room for 2 hours, In case group, IOP in 10 of 22 eyes rose more than 1. 07kPa(1kPa = 7.5mmHg), in 12 eyes less than 1.07kPa or had no changes; appositional angle closure were found by Goldmann gonioscopy in 8 eyes : 3 eyes in two quadrants, 5 eyes in more than two quadrants; the appositional angle closure was found by UBM in 15 eyes; 3 eyes in one quadrants, 5 eyes in two quadrants, 7 eyes  相似文献   
15.
Zusammenfassung Eine neu aufgetretene Dyspnoesymptomatik und eine symmetrische, apikal betonte retikulonodul?re Zeichnungsvermehrung im R?ntgen-Thorax bei jungen rauchenden Erwachsenen müssen an das seltene Krankheitsbild der pulmonalen Histiocytosis X denken lassen. Klinischer Befund, laborchemische- und Lungenfunktionsuntersuchungen zeigen unspezifische Befunde. Neue radiologische Verfahren wie die hochaufl?sende Computertomographie (HRCT) leisten bei gezielter Indikationsstellung eine entscheidende differentialdiagnostische Hilfestellung. Dieser Fall verdeutlicht die M?glichkeit einer Diagnosesicherung durch transbronchiale Biopsien unter Verzicht auf offene Lungenbiopsien. Eine ambulante Diagnostik war m?glich, das h?here Risiko eines operativen Eingriffes konnte vermieden werden. Die Indikation zur Therapie ist nicht gesichert und wird daher durch den Grad der subjektiven bzw. funktionellen Einschr?nkung sowie den Verlauf bestimmt.  相似文献   
16.
Twenty five cases, including 26 eyes with retinal vein occlusion (RVO) were examined by means of the electro-oculogram. The results showed that 23 of the 26 eyes suffering from RVO exhibited abnormalities of the electro-oculogram (EOG). The potential difference and Arden ratio in the RVO eyes were lower than those in the normal eyes (P<0.01). The more the visual acuity of ill eyes was decreased, the higher the abnormal rate of EOG in ill eyes was. 14 eyes had the visual acuity less than 0.1, whose EOGs were abnortmal. Six eyes had the visual acuity from 0. 2 to 0. 4, in which the EOGs of 5 eyes were abnormal. Six eyes had the visual acuity more than 0. 5, a-mong which the EOGs of 4 eyes were abnormal. Based on the above observations, it may be considered that the circulatory disturbance resulting from RVO damages not only the internal layer but also the external layer of the retina. We suggest that EOG is a useful method for distingquishing lesions caused by RVO and may reflect the functional condition  相似文献   
17.
分别采用联合火箭免疫电泳技术和酶法对49例冠心病患者和50例健康人血清载脂蛋白 A_1(apoA_1),载脂蛋白 B_(100)(apoB_(100)),以及血清总胆固醇(TC)、甘油三酯(TG),高密度脂蛋白胆固醇(HDL—ch)的含量进行了测定。结果冠心病患者血清 apoB_(100)(0.99±0.26g/L)明显高于健康人(0.62±0.18g/L);而apoA_1/apoB_(100)比值(1.22±0.35)则明显低于健康人(2.12±0.49);TC,TG,HDL-ch 的含量亦有统计学意义。提示,在预示冠心病危险因素的各种脂类及脂蛋白中,以 apoB_(100)增高 apoA_1/apoB_(100)比值降低最为灵敏,最为准确,且高于单纯测定TC,TG 和 HDL-ch。  相似文献   
18.
Four cases of microtia association with hemifacial aplasia were repaired by one-stage reconstruction. The operations included external ear reconstruction and correction of facial deformity with free vascularized dermis fat flaps. All were successful, the results were satisfied. The method and the device of the operation are described in detail. The advantages of the technique are discussed.  相似文献   
19.
周桂平 《护理研究》2007,21(32):2939-2939
皮肤慢性溃疡是较难治愈的疾病,自2003年采用橡皮生肌膏外用配合氦氖激光照射治疗皮肤溃疡取得良好疗效。现报告如下。1病例介绍[例1]病人,男,45岁。5年前因外伤致足跟部皮肤破损并感染,经各种治疗无效,伤口长年不愈,于2005年3月12日来我院就诊。查体:全身情况尚好,左足跟可见3  相似文献   
20.
OBJECTIVE: To evaluate the effect of hyperfractionated radiation therapy and concomitant chemotherapy for inoperable stage III non-small cell lung cancer (NSCLC). METHODS: Seventy patients were randomized equally into two group. The therapy group received radiotherapy with hyperfractionated radiation therapy combined with concomitant chemotherapy, and the control group was treated with chemotherapy only. RESULT: The overall response rate, including the rate of both complete (CR) and partial responses (PR), in the therapy group was 60.0% with a CR rate of 8.6%. The overall response rate in the control group was 40.0% with a CR rate of 5.7%. The difference in overall response rate was statistically significant between the two groups (P<0.05). The median survival time, 1- and 2-years survival rate were 12.8 months, 48.6%, and 25.7%, respectively, in the hyperfractionated radiotherapy group, and 9.4 months, 34.3%, and 17.1%, respectively, in the chemotherapeutic group (P 0.031). The major toxic effects of the chemotherapy were myelosuppression and radiation esophagitis. CONCLUSION: Hyperfractionated radiation therapy plus concomitant chemotherapy with paclitaxel for inoperable stage III NSCLC improves the short-term response of the patients, but fail to raise the survival rate.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号