全文获取类型
收费全文 | 9731篇 |
免费 | 1022篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 178篇 |
儿科学 | 274篇 |
妇产科学 | 160篇 |
基础医学 | 1457篇 |
口腔科学 | 288篇 |
临床医学 | 1176篇 |
内科学 | 1943篇 |
皮肤病学 | 116篇 |
神经病学 | 673篇 |
特种医学 | 331篇 |
外国民族医学 | 1篇 |
外科学 | 1360篇 |
综合类 | 185篇 |
一般理论 | 7篇 |
预防医学 | 1121篇 |
眼科学 | 167篇 |
药学 | 737篇 |
中国医学 | 7篇 |
肿瘤学 | 591篇 |
出版年
2022年 | 78篇 |
2021年 | 179篇 |
2020年 | 103篇 |
2019年 | 138篇 |
2018年 | 157篇 |
2017年 | 128篇 |
2016年 | 158篇 |
2015年 | 190篇 |
2014年 | 255篇 |
2013年 | 314篇 |
2012年 | 479篇 |
2011年 | 484篇 |
2010年 | 298篇 |
2009年 | 282篇 |
2008年 | 431篇 |
2007年 | 455篇 |
2006年 | 430篇 |
2005年 | 437篇 |
2004年 | 425篇 |
2003年 | 395篇 |
2002年 | 339篇 |
2001年 | 299篇 |
2000年 | 344篇 |
1999年 | 309篇 |
1998年 | 141篇 |
1997年 | 123篇 |
1996年 | 111篇 |
1995年 | 119篇 |
1994年 | 71篇 |
1993年 | 74篇 |
1992年 | 182篇 |
1991年 | 196篇 |
1990年 | 174篇 |
1989年 | 188篇 |
1988年 | 149篇 |
1987年 | 153篇 |
1986年 | 130篇 |
1985年 | 168篇 |
1984年 | 130篇 |
1983年 | 111篇 |
1982年 | 78篇 |
1981年 | 79篇 |
1979年 | 119篇 |
1978年 | 92篇 |
1976年 | 70篇 |
1975年 | 64篇 |
1974年 | 92篇 |
1973年 | 76篇 |
1971年 | 61篇 |
1970年 | 61篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
W Frank R Karlstadt F Rockhold R Palmer M Malone M Young 《Clinical pharmacology and therapeutics》1989,46(2):234-239
The relative effectiveness of intermittent infusions and primed continuous infusions of cimetidine in the maintenance of intragastric pH greater than or equal to 4.0 was evaluated in a double-blind crossover trial in 26 patients who had active or healed gastroduodenal ulcers. During the intermittent phase, each patient received 300 mg cimetidine intravenously every 6 hours. During the continuous infusion phase, each patient was given a continuous infusion of 37.5 mg cimetidine per hour, preceded by a priming dose of 300 mg cimetidine that was given for 15 minutes. Intragastric pH was monitored continuously. During the last 12 hours of the study, the continuous infusion regimen provided 20% more time in which the pH was more [corrected] than 4.0 with 25% less medication than did the intermittent infusion regimen. 相似文献
42.
Fine needle aspiration cytology: an in vitro study of cell yield 总被引:1,自引:0,他引:1
M N Hartley D J Tuffnell J L Hutton M Palmer M S Al-Jafari 《The British journal of surgery》1988,75(4):380-381
To investigate the effect of needle size and number of passes into a tumour mass on the cell yield from a fine needle aspirate, an in vitro study was undertaken in 19 consecutive tumours removed surgically for biopsy. Different needle sizes (23G, 21G, 19G) passed in random order, five, ten and fifteen times into the tumours, were compared. The type of tumour, needle size and number of passes independently and significantly influenced cell yield. A 21G(green) needle passed into the tumour at least 10 times was the most efficient in obtaining cells. This in vitro study could explain the variation in the reported accuracy of fine needle aspiration cytology from groups using different techniques and is perhaps one reason why the highest diagnostic accuracy and the lowest rate of unsatisfactory aspirates comes from a centre which uses a 21G needle and at least 10 passes through the tumour. 相似文献
43.
S T Bartlett W J McCarthy A S Palmer W R Flinn J J Bergan J S Yao 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(8):1004-1008
Beh?et's disease is characterized by recurrent ulcers of the mouth and genitalia and relapsing iritis. It is now recognized as a chronic multisystem disease affecting the skin, mucous membranes, eye, joints, central nervous system, and blood vessels. One of the known vascular complications of Beh?et's disease is aneurysm formation or venous thrombosis. The two patients with Beh?et's disease in this report developed multiple aneurysms over a short time span. Vascular surgeons dealing with young adults with peripheral aneurysms must be aware of this uncommon yet challenging clinical entity. 相似文献
44.
Adherence to continuous positive airway pressure treatment in patients with Alzheimer's disease and obstructive sleep apnea. 总被引:2,自引:0,他引:2
Liat Ayalon Sonia Ancoli-Israel Carl Stepnowsky Matthew Marler Barton W Palmer Lianqi Liu Jose S Loredo Jody Corey-Bloom Deborah Greenfield Jana Cooke 《The American journal of geriatric psychiatry》2006,14(2):176-180
OBJECTIVE: This analysis examined whether patients with Alzheimer disease (AD) tolerate continuous positive airway pressure (CPAP). METHOD: Thirty patients with AD were randomized to CPAP or sham CPAP and completed sleep, depression, and quality-of-life questionnaires. Participants could choose to continue treatment after the trial. RESULTS: Patients wore CPAP for 4.8 hours per night. More depressive symptoms were associated with worse adherence (rS=-0.37; N=30, p<0.04). Patients who continued using CPAP had fewer depressive symptoms (t [19]=2.45, p=0.02) and better adherence (t [19]=2.32, p=0.03) during the trial. CONCLUSION: Patients with AD with obstructive sleep apnea can tolerate CPAP. Adherence and long-term use may be more difficult among those patients with more depressive symptoms. 相似文献
45.
Malignant fibrous histiocytoma of the lung 总被引:1,自引:0,他引:1
46.
Characterization of the L-arginine:nitric oxide pathway in human platelets. 总被引:13,自引:0,他引:13
下载免费PDF全文
![点击此处可从《British journal of pharmacology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
1. The activation of the L-arginine: nitric oxide (NO) pathway during aggregation of human platelets by adenosine 5'-diphosphate (ADP), arachidonic acid, thrombin and the calcium ionophore A23187 and its inhibition by NG-monomethyl-L-arginine (L-NMMA), NG-nitro-L-arginine methyl ester (L-NAME) and N-iminoethyl-L-ornithine (L-NIO) were studied. The inhibition of the cytosolic platelet NO synthase by these compounds was also examined. 2. Platelet aggregation induced by ADP (1-10 microM) and arachidonic acid (0.1-10 microM), but not that induced by thrombin (1-30 mu ml-1) or A23187 (1-10 nM), was inhibited by L-, but not D-arginine (1-30 microM). However, in the presence of a subthreshold concentration of prostacyclin (0.1 nM) or of M & B 22948 (1 microM), a selective inhibitor of guanosine 3':5'-cyclic monophosphate (cyclic GMP) phosphodiesterase, L-arginine caused concentration-dependent inhibition of aggregation induced by all of these aggregating agents. 3. L-NMMA, L-NAME and L-NIO (all at 1-30 microM), but not their D-enantiomers, enhanced to the same extent platelet aggregation induced by ADP, arachidonic acid and thrombin without affecting that induced by A23187. 4. In the presence of 300 microM L-arginine, the NO synthase in platelet cytosol was inhibited by L-NMMA, L-NAME and L-NIO with IC50s of 74 +/- 9, 79 +/- 8 and 8.5 +/- 1.5 microM (n = 3), respectively. 5. These results indicate that the L-arginine: NO pathway in human platelets plays a role in the modulation of platelet aggregation. 相似文献
47.
Neuropsychological tests of frontal lobe functions were undertaken in 46 chronic schizophrenic patients who were also rated for movement disorders. Tardive dyskinesia was found to have significant associations with most of these psychological tests. The possible mechanisms are discussed within the context of known neostriatal psychological functions. 相似文献
48.
S R Tabet D L Palmer W H Wiese R E Voorhees D R Pathak 《American journal of public health》1992,82(8):1151-1154
A survey of persons soliciting sex in an area known to be frequented by prostitutes in Albuquerque, NM, included 43 females and 66 males. Seroprevalence rates found in this population-based study were as follows: human immunodeficiency virus type 1 (HIV-1), 3%; hepatitis B, 39%; hepatitis C, 45%. Increased age, intravenous drug use, and condom use were independent risk factors for hepatitis B. Female gender and intravenous drug use were independent risk factors for hepatitis C. Neither sharing injection equipment nor engaging in receptive anal intercourse was independently associated with hepatitis B or C. 相似文献
49.
50.
The pharmacokinetics of ondansetron after intravenous injection in healthy volunteers phenotyped as poor or extensive metabolisers of debrisoquine. 总被引:2,自引:1,他引:1
下载免费PDF全文
![点击此处可从《British journal of clinical pharmacology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
E I Ashforth J L Palmer A Bye A Bedding 《British journal of clinical pharmacology》1994,37(4):389-391
The pharmacokinetics of the 5-HT3 receptor antagonist ondansetron following an 8 mg i.v. dose were investigated in 12 subjects previously phenotyped with debrisoquine. Six subjects were poor metabolisers (debrisoquine metabolic ratios 29-131) and six were extensive metabolisers (debrisoquine metabolic ratios 0.45-3.4). There was no significant difference in AUC, Cmax, CL or t1/2 between the poor and extensive metabolisers. It is concluded that ondansetron clearance is not mediated exclusively by cytochrome P-450 2D6. 相似文献