全文获取类型
收费全文 | 1692484篇 |
免费 | 126461篇 |
国内免费 | 3778篇 |
专业分类
耳鼻咽喉 | 21730篇 |
儿科学 | 55639篇 |
妇产科学 | 46151篇 |
基础医学 | 241209篇 |
口腔科学 | 48741篇 |
临床医学 | 151305篇 |
内科学 | 333499篇 |
皮肤病学 | 38653篇 |
神经病学 | 131136篇 |
特种医学 | 63870篇 |
外国民族医学 | 242篇 |
外科学 | 257238篇 |
综合类 | 38945篇 |
现状与发展 | 4篇 |
一般理论 | 531篇 |
预防医学 | 124223篇 |
眼科学 | 40211篇 |
药学 | 123598篇 |
7篇 | |
中国医学 | 4475篇 |
肿瘤学 | 101316篇 |
出版年
2021年 | 12784篇 |
2019年 | 13523篇 |
2018年 | 19950篇 |
2017年 | 15215篇 |
2016年 | 16614篇 |
2015年 | 18960篇 |
2014年 | 26214篇 |
2013年 | 37944篇 |
2012年 | 52726篇 |
2011年 | 55418篇 |
2010年 | 32776篇 |
2009年 | 30693篇 |
2008年 | 51519篇 |
2007年 | 54799篇 |
2006年 | 55254篇 |
2005年 | 52542篇 |
2004年 | 50742篇 |
2003年 | 48148篇 |
2002年 | 46371篇 |
2001年 | 91783篇 |
2000年 | 93606篇 |
1999年 | 76960篇 |
1998年 | 19717篇 |
1997年 | 17267篇 |
1996年 | 17391篇 |
1995年 | 16742篇 |
1994年 | 15289篇 |
1993年 | 14071篇 |
1992年 | 57383篇 |
1991年 | 55271篇 |
1990年 | 52971篇 |
1989年 | 50748篇 |
1988年 | 46131篇 |
1987年 | 44937篇 |
1986年 | 42227篇 |
1985年 | 39989篇 |
1984年 | 29349篇 |
1983年 | 24909篇 |
1982年 | 13898篇 |
1979年 | 25531篇 |
1978年 | 17574篇 |
1977年 | 14906篇 |
1976年 | 13874篇 |
1975年 | 14565篇 |
1974年 | 17631篇 |
1973年 | 16944篇 |
1972年 | 15675篇 |
1971年 | 14454篇 |
1970年 | 13431篇 |
1969年 | 12517篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
The hepatotropic effect of nonsteroidal anti-inflammatory drugs (NSAID) such as indomethacin, voltaren, piroxicam, phenylbutazon, mefenamic acid was studied. It was found that according to their level of the pharmacological protection of the liver against tetrachlormethan these agents may be arranged in the following sequence: mefenamic acid, phenylbutazon, voltaren, piroxicam. The hepatoprotective effect of NSAID correlates with the antioxidant properties and fails to correlate with the antioxidant ones. The hepatotoxic effect of NSAID was determined by their ability to suppress synthesis of prostaglandins. 相似文献
962.
The effect of oxitropium bromide (Ba253), a quaternary scopolamine derivative, on the resting tonus and agonist-induced contraction of isolated guinea pig airway smooth muscle and on the anaphylactic release of histamine and immunoreactive leukotrienes (i-LTs) from lung fragments were investigated and compared with those of Sch1000, atropine and isoproterenol. Ba253 dose-dependently inhibited the acetylcholine (ACh)-induced contraction of the isolated trachea and lung parenchyma. The degree of inhibitory potency was similar to that of Sch1000 and 10 times higher than that of atropine. Ba253 minimally influenced the resting tonus or contractions induced by other agonists including histamine, serotonin and LTD4. Sch1000 and atropine had similar or slightly stronger inhibitory effects on the tonus and contractions than Ba253. On the other hand, low concentrations of isoproterenol solely relaxed the resting tonus and inhibited the the agonist-induced contractions of both preparations. Neither Ba253 nor Sch1000 inhibited the anaphylactic release of histamine and LTs from both guinea pig and human lung fragments, but both mediator releases from either species were slightly inhibited with dose-dependency by atropine and potently inhibited by isoproterenol. From these results, it is suggested that Ba253 is a relatively specific antagonist to cholinergic receptors and might be possibly effective as an inhalant for asthma. 相似文献
963.
964.
Three cases of voluntary posterior instability of the shoulder are presented. They have all responded well to a program of electromyographic monitored biofeedback. This method offers a means of enhancing the results of nonoperative treatment. 相似文献
965.
S Raptis 《Der Internist》1987,28(4):243-253
966.
967.
Spinal antinociceptive effects of adenosine compounds in mice 总被引:1,自引:0,他引:1
The effects of injecting ATP, ADP, AMP, adenosine and adenine intrathecally on the pain response induced by the injection of substance P (10 ng/mouse) intrathecally were studied. All the compounds except adenine inhibited the pain response in a dose-related manner. The ED50 values of ATP, ADP, AMP and adenosine were 2.10, 0.93, 0.88 and 0.48 micrograms/mouse, respectively. Pretreatment with theophylline at a dose of 100 mg/kg p.o. markedly diminished all the antinociceptive effects. The effect of adenosine was not affected by s.c. injection of naloxone. These results suggest the existence of adenosine receptors which modulate spinal nociceptive sensory processing, independently of the endogenous opiate system. 相似文献
968.
Reported in this paper are postoperative results recorded from 120 patients, 3 years after selective proximal vagotomy for uncomplicated duodenal ulcer. There was no intraoperative lethality and no recurrence in 96.7 per cent of all cases, while Visick grades I on II were recorded from 98.2 per cent. Radiologically and gastroscopically detected pathological processes receded soon. Average postoperative reduction in acid secretion was 66.2 per cent in BAO and 46.8 per cent in MAO. Acid values re-increased thereafter, and three years later reduction rates still amounted to 43.7 per cent in BAO and 28.6 per cent in MAO. Indications for proximal gastric vagotomy are discussed in some detail. 相似文献
969.
970.
Experience with the 'skew flap' below-knee amputation 总被引:3,自引:0,他引:3
A review of 353 lower limb amputations over the last 7 years has been performed to assess the results of the skew flap myoplastic below-knee amputation which was introduced in April 1983 because of reported advantages in terms of wound healing and earlier ambulation. Comparing the first 3 1/2 year period with the second, the total number of amputations decreased by 31 per cent. The number of above-knee amputations remained similar in the two periods (82,62), whilst the number of Gritti-Stokes amputations fell from 79 to 21 (0.001 greater than P greater than 0.01). The proportion of below-knee (BK) amputations increased from 50 (23.7 per cent) to 59 (41.5 per cent) (0.01 greater than P greater than 0.025). The groups were comparable in terms of previous vascular surgery and co-existing medical conditions. The time to full stump healing was significantly shorter in the skew flap group compared with the earlier Burgess type BK amputation (P = 0.001), and there was a trend to fewer stump failures in the skew flap group. We therefore feel that the skew flap amputation gives superior results to the Burgess BK amputation in terms of healing and a lower complication rate, allowing a higher proportion of BK amputations to be performed. A prospective randomized trial of the two techniques is in hand to determine the accuracy of this hypothesis. 相似文献