全文获取类型
收费全文 | 656362篇 |
免费 | 46541篇 |
国内免费 | 15008篇 |
专业分类
耳鼻咽喉 | 8100篇 |
儿科学 | 12728篇 |
妇产科学 | 16047篇 |
基础医学 | 89527篇 |
口腔科学 | 17905篇 |
临床医学 | 61513篇 |
内科学 | 122222篇 |
皮肤病学 | 12623篇 |
神经病学 | 43387篇 |
特种医学 | 23591篇 |
外国民族医学 | 182篇 |
外科学 | 92741篇 |
综合类 | 42166篇 |
现状与发展 | 40篇 |
一般理论 | 117篇 |
预防医学 | 37157篇 |
眼科学 | 16512篇 |
药学 | 58654篇 |
192篇 | |
中国医学 | 13568篇 |
肿瘤学 | 48939篇 |
出版年
2023年 | 3837篇 |
2022年 | 9270篇 |
2021年 | 13142篇 |
2020年 | 9369篇 |
2019年 | 9769篇 |
2018年 | 12182篇 |
2017年 | 10214篇 |
2016年 | 9903篇 |
2015年 | 13626篇 |
2014年 | 17459篇 |
2013年 | 18853篇 |
2012年 | 26834篇 |
2011年 | 28455篇 |
2010年 | 17693篇 |
2009年 | 14903篇 |
2008年 | 22071篇 |
2007年 | 22577篇 |
2006年 | 22171篇 |
2005年 | 20732篇 |
2004年 | 16974篇 |
2003年 | 16017篇 |
2002年 | 14681篇 |
2001年 | 36466篇 |
2000年 | 37440篇 |
1999年 | 31547篇 |
1998年 | 8656篇 |
1997年 | 7540篇 |
1996年 | 6333篇 |
1995年 | 5882篇 |
1994年 | 5253篇 |
1993年 | 4386篇 |
1992年 | 20212篇 |
1991年 | 18924篇 |
1990年 | 17908篇 |
1989年 | 17587篇 |
1988年 | 15992篇 |
1987年 | 15230篇 |
1986年 | 14054篇 |
1985年 | 13119篇 |
1984年 | 8826篇 |
1983年 | 7268篇 |
1979年 | 7369篇 |
1978年 | 4539篇 |
1977年 | 3968篇 |
1975年 | 3828篇 |
1974年 | 4427篇 |
1973年 | 4265篇 |
1972年 | 4152篇 |
1971年 | 3996篇 |
1969年 | 3654篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
102.
103.
The effect of the traditional Chinese medicinal herbs enema and enteric-coated capsules in the treatment of ulcerative colitis (UC) were compared in 260 cases. The immune complexes and the dynamic change of autoantibodies were monitored in 28 out of the 260 cases before and after treatment. The following results were observed. (1) There was no significant difference in the total effective rate between the enema group and the oral capsule group (93.3% and 87.5% respectively), but the recovery rates of purulent hemafecia, mucusfecia and erosion accompanying colitis, etc. in the former group were higher than those in the latter (P less than 0.01). (2) The circulating immune complexes were found 43 times above the normal range in 17 cases with positive rate 60.7%, and tended to decrease as the condition became better after treatment. Antinuclear antibodies were determined by the indirect fluorescent immune method and the indirect enzyme labelling method and the positive rates were 53.6% and 64.7% respectively, both being much higher than those in the controls (P less than 0.01). 相似文献
104.
T Uno M Takamatsu Y Inoue Y Kawahata K Iuchi G Tsukamoto 《Journal of medicinal chemistry》1987,30(12):2163-2169
A series of 6-fluoro- and 6,8-difluoro-7-(azole substituted)-1,4-dihydro-4-oxo-3-quinolinecarboxylic acids were prepared. Structure-activity relationship studies indicated that the antibacterial potency was better when the 6,8-substituents were fluorine atoms and the 7-substituent was either 1-imidazolyl, 20, or 4-methyl-1-imidazolyl, 25. From the results of studies on pharmacokinetic profile and toxicity, 20 and 25 were found to possess excellent antibacterial activities and to show high blood levels after oral administration to mice with low toxicity. 相似文献
105.
106.
Y Abiko K Ichihara K Sakai H Sashida T Ishibashi 《Methods and findings in experimental and clinical pharmacology》1986,8(5):271-278
This paper describes a method by which antianginal drugs can be evaluated in the dog heart in situ. Myocardial pH was measured continuously by a micro glass pH electrode inserted in the left ventricular endocardial layers of the dog anesthetized with pentobarbital. Occlusion of the left anterior descending coronary artery (LAD) decreased myocardial pH, and release of the LAD restored the pH. The myocardial acidosis induced by ischemia was metabolic in nature and accompanied by a decrease in the levels of adenosine triphosphate and creatine phosphate and an increase in the levels of lactate in the myocardium. Drugs were injected intravenously 30 min after incomplete (partial) occlusion ot the LAD, lasting until 60 min after drug injection. Propranolol, atenolol, and sotalol markedly attenuated the myocardial pH that had been decreased by LAD occlusion. Nitroglycerin, diltiazem, and nicorandil also attenuated the pH, but these drugs were less active in attenuating myocardial acidosis. Dipyridamole, nifedipine, and beta-2 adrenoceptor antagonists were least active in this regard. It is concluded that myocardial pH can be used as an indicator of myocardial regional ischemia and utilized for evaluation of antianginal drugs. 相似文献
107.
W F Rayburn M Z Johnson K L Hoffman S M Donn R M Nelson 《American journal of perinatology》1987,4(2):98-101
A goal for the obstetrician and neonatologist is to screen for risk factors associated with intraventricular hemorrhage (IVH) in the low-birthweight infant. Perinatal events that lead to neonatal metabolic and cardiovascular derangements seem to provoke IVH, and conflicting reports have implicated labor as being contributory. A fetal heart rate (FHR) abnormality during premature labor may be a predictor of subsequent neonatal IVH. For this reason, 5 years of FHR tracings at two university medical centers were reviewed for inborn infants who were delivered after premature labor and weighed less than or equal to 2000 gm. Sixty-four infants developed IVH, but pre-existing labor with a discernible FHR pattern was recorded in only 38 (59%) cases. Interpretations were reassuring in 17 (45%) cases, suspicious in 7 (18%) cases, and ominous in 14 (37%) cases. This proportion of FHR patterns was not significantly different from a matched group of premature infants without IVH during the same period. Interpretations of intrapartum FHR patterns of low-birthweight infants are limited, especially before 30 weeks gestation, and not useful in predicting neonatal IVH. 相似文献
108.
Georgios K Glantzounis Henryk J Salacinski Wenxuan Yang Brian R Davidson Alexander M Seifalian 《Liver transplantation》2005,11(9):1031-1047
Oxidative stress is an important factor in many pathological conditions such as inflammation, cancer, ageing and organ response to ischemia-reperfusion. Humans have developed a complex antioxidant system to eliminate or attenuate oxidative stress. Liver ischemia-reperfusion injury occurs in a number of clinical settings, including liver surgery, transplantation, and hemorrhagic shock with subsequent fluid resuscitation, leading to significant morbidity and mortality. It is characterized by significant oxidative stress but accompanied with depletion of endogenous antioxidants. This review has 2 aims: firstly, to highlight the clinical significance of liver ischemia-reperfusion injury, the underlying mechanisms and the main pathways by which the antioxidants function, and secondly, to describe the new developments that are ongoing in antioxidant therapy and to present the experimental and clinical evidence about the role of antioxidants in modulating hepatic ischemia-reperfusion injury. 相似文献
109.
眼针治疗阵发性室上性心动过速120例的即时疗效观察 总被引:2,自引:0,他引:2
目的:观察眼针对阵发性室上性心动过速的即时疗效。方法:选择符合诊断标准的门诊患者120例,针其眼针穴区:心区和上焦区。针后30分钟描记心电图,计算心率,观察眼针对阵发性室上性心动过速的影响。结果:显效103例,占85.83%;有效9例,占7.5%;无效8例,占6.66%;总有效率93.33%.结论:眼针对阵发性室上性心动过速有较好的即时疗效。 相似文献
110.
Intracranial pathology is a common and important complication in extremely low birth weight babies. Lenticulostriate vasculopathy (LSV) is an abnormal finding on cranial ultrasounds of sick babies and has been associated with congenital infection, chromosomal aberration and twin-to-twin transfusion. We describe a previously unreported situation of LSV being detected in both donor and recipient twin. This pair of monochorionic, diamniotic twins was admitted to the Neonatal Intensive Care Unit at 28 weeks of gestation. The mother underwent an emergency caesarean section because ultrasound and Doppler studies showed stage III twin-to-twin transfusion syndrome. The first twin weighed 998 g and second twin weighed 600 g. The first twin had an uneventful stay, whereas the second twin needed prolonged continuous positive airway pressure and indomethacin for patent ductus arteriosus. Both of them developed LSV. The clinical significance of this condition on the neuro-developmental outcome of a neonate has not yet been fully determined. 相似文献