全文获取类型
收费全文 | 2353篇 |
免费 | 213篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 113篇 |
妇产科学 | 23篇 |
基础医学 | 328篇 |
口腔科学 | 53篇 |
临床医学 | 245篇 |
内科学 | 538篇 |
皮肤病学 | 17篇 |
神经病学 | 164篇 |
特种医学 | 46篇 |
外科学 | 367篇 |
综合类 | 69篇 |
一般理论 | 1篇 |
预防医学 | 208篇 |
眼科学 | 14篇 |
药学 | 244篇 |
中国医学 | 1篇 |
肿瘤学 | 130篇 |
出版年
2021年 | 33篇 |
2019年 | 37篇 |
2018年 | 36篇 |
2017年 | 28篇 |
2016年 | 32篇 |
2015年 | 30篇 |
2014年 | 48篇 |
2013年 | 70篇 |
2012年 | 108篇 |
2011年 | 114篇 |
2010年 | 53篇 |
2009年 | 59篇 |
2008年 | 100篇 |
2007年 | 104篇 |
2006年 | 97篇 |
2005年 | 95篇 |
2004年 | 76篇 |
2003年 | 89篇 |
2002年 | 83篇 |
2001年 | 83篇 |
2000年 | 87篇 |
1999年 | 76篇 |
1998年 | 19篇 |
1997年 | 20篇 |
1995年 | 27篇 |
1994年 | 26篇 |
1993年 | 18篇 |
1992年 | 65篇 |
1991年 | 41篇 |
1990年 | 47篇 |
1989年 | 67篇 |
1988年 | 53篇 |
1987年 | 46篇 |
1986年 | 41篇 |
1985年 | 34篇 |
1984年 | 29篇 |
1983年 | 20篇 |
1982年 | 23篇 |
1980年 | 17篇 |
1979年 | 17篇 |
1978年 | 19篇 |
1977年 | 23篇 |
1974年 | 34篇 |
1973年 | 32篇 |
1972年 | 27篇 |
1971年 | 26篇 |
1970年 | 27篇 |
1969年 | 25篇 |
1967年 | 26篇 |
1966年 | 19篇 |
排序方式: 共有2570条查询结果,搜索用时 15 毫秒
1.
Marilyn Sawyer Sommers 《Journal of nursing scholarship》2006,38(4):314-320
PURPOSE: To discuss injury research as a phenomenon of concern in nursing science. ORGANIZING CONSTRUCT: Injury is defined as the physical damage that results when the human body is briefly subjected to intolerable levels of energy. It is the leading cause of death in the first 4 decades of life in high-income nations and is second only to infectious diseases as a leading cause of death in low- and middle-income nations. METHODS: Review and discussion of relevant scientific and theoretical literature in both injury and nursing science. FINDINGS: Nurse scientists can apply unique perspectives to increase understanding of injury and its consequences. Fertile areas for nursing inquiry include identifying people at risk, developing models to explain the association between risk-taking and injury, testing interventions to prevent and limit injury, and creating and refining interventions that are culturally relevant to subpopulations most at risk for injury. CONCLUSIONS: The mandate to improve global heath should lead to nursing inquiry about this phenomenon, including developing and testing interventions to prevent and reduce injury. 相似文献
2.
3.
4.
5.
W. D. Fraser T. C. Stamp R. A. Creek J. P. Sawyer C. Picot 《Postgraduate medical journal》1997,73(862):496-502
A multicentre, randomised, placebo-controlled, dose-ranging study was conducted to investigate the therapeutic activity and sustained efficacy of tiludronate (200 mg, 400 mg and 600 mg once daily) taken orally for 12 weeks in patients with Paget''s disease. Serum alkaline phosphatase concentrations were compared with baseline at weeks 12 and 24; treatment success was defined as a 50% reduction compared with baseline. Changes in the hydroxyproline: creatinine ratio were also measured. Pain was assessed using the Huskisson Visual Analogue Scale and by questionnaire. Patients completing at least 11 weeks of treatment were followed-up 18 months later by postal questionnaire. Significantly greater numbers of patients in the tiludronate groups successfully responded to treatment compared with the placebo group. A dose-response was observed; the percentage of patients responding to treatment being 31% (200 mg), 52% (400 mg) and 82% (600 mg) at week 12 and 45% (200 mg), 70% (400 mg) and 82% (600 mg) at week 24. Tiludronate treatment also significantly reduced hydroxyproline: creatinine ratios compared with placebo, again showing a dose response. Dose-related gastrointestinal symptoms were the commonest adverse events, occurring in 2.4%, 11.0%, 5.5% and 18.9% of patients receiving placebo and tiludronate 200, 400 and 600 mg daily, respectively. The response to oral tiludronate was sustained for more than 18 months in some patients and there was evidence of a reduction in the longer term complications of the disease. These results show that oral tiludronate is an effective, well-tolerated treatment for Paget''s disease; the 400 mg once daily dose appears to offer the optimum balance of efficacy and tolerance. 相似文献
6.
7.
8.
Solid-phase synthesis of 16 potent (selective and nonselective) in vivo antagonists of oxytocin 总被引:7,自引:0,他引:7
M Manning M Kruszynski K Bankowski A Olma B Lammek L L Cheng W A Klis J Seto J Haldar W H Sawyer 《Journal of medicinal chemistry》1989,32(2):382-391
We describe the synthesis and some pharmacological properties of 16 new in vivo antagonists of oxytocin. These are based on modifications of three peptides: A, B, and C. A is our previously reported potent and selective antagonist of the vasopressor (V1 receptor) responses to arginine-vasopressin (AVP)/weak oxytocin antagonist, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid), 2-O-methyltyrosine]arginine-vasopressin (d(CH2)5[Tyr(Me)2]AVP. B reported here, the Ile3 analogue of A, is d(CH2)5[Tyr(Me)2]AVT (5 below) and C is our previously reported potent nonselective oxytocin antagonist/AVP V1 antagonist, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid),2-O- methyltyrosine,8-ornithine]vasotocin (d(CH2)5[Tyr(Me)2]OVT). The following substitutions and deletions, alone or in combination, were employed in A, B, and C: 1-deaminopenicillamine (dP); D-Tyr(Alk)2 (where Alk = Me or Et), D-Phe2; Val4, Thr4; delta 3-Pro7; Lys8, Cit8; desGly9, desGly-NH2(9), Ala-NH2(9); Leu-NH2(9); Arg-NH2(9). The 16 new analogues are (1) d(CH2)5[D-Tyr(Me)2]AVP, (2) d(CH2)5[D-Tyr(Me)2, Val4,delta 3-Pro7]AVP, (3) d(CH2)5[D-Tyr-(Et)2, Val4,Lys8]VP, (4) d(CH2)5[D-Tyr(Et)2,Val4,Cit8]VP, (5) d(CH2)5[Tyr(Me)2]AVT, (6) d(CH2)5[Tyr(Me)2,Lys8]VT, (7) dP[Tyr(Me)2]AVT, (8) dP[Tyr(Me)2,Val4]AVT, (9) d(CH2)5[D-Tyr(Me)2, Val4]AVT, (10) d(CH2)5[D-Phe2,Val4]AVT, (11) d(CH2)5[Tyr(Me)2,Thr4]OVT, (12) d(CH2)5[Tyr(Me)2,Thr4,Ala-NH2(9)]OVT, (13) d(CH2)5[Tyr(Me)2,Thr4,Leu-NH2(9)]OVT, (14) d(CH2)5[Tyr(Me)2,Thr4,Arg-NH2(9)]OVT, (15) desGly-NH2(9),d(CH2)5[Tyr(Me)2,Thr4]OVT, (16) desGly9,d(CH2)5[Tyr(Me)2,Thr4]OVT. 1-4 are analogues of A, 5-10 are analogues of B, and 11-16 are analogues of C. Their protected precursors were synthesized either entirely by the solid-phase method or by a combination of solid-phase and solution methods (1 + 8 or 8 + 1 couplings). All analogues were tested in rats for agonistic and antagonistic activities in oxytocic (in vitro, without and with Mg2+, and in vivo) assays as well as by antidiuretic and vasopressor assays. All analogues exhibit potent oxytocic antagonism in vitro and in vivo. With an in vitro pA2 (in the absence of Mg2+) = 9.12 +/- 0.09, dP[Tyr(Me)2]AVT is (7) one of the most potent in vitro oxytocin antagonists reported to date. Fifteen of these analogues (all but 6) appear as potent or more potent in vivo oxytocin antagonists than C (pA2 = 7.37 +/- 0.17). Analogues 1-9 and 14 are potent AVP V1 antagonists. Their anti-V1 pA2 values range from 7.92 to 8.45. They are thus nonselective oxytocin antagonists.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
9.
10.
Alexander Kulik Marc Ruel Michael E Bourke Lynn Sawyer John Penning Howard J Nathan Thierry G Mesana Pierre Bédard 《European journal of cardio-thoracic surgery》2004,26(4):694-700
OBJECTIVE: Non-steroidal anti-inflammatory drugs (NSAIDs) are routinely used after coronary artery bypass surgery (CABG), yet their effects have seldom been evaluated in randomized controlled settings. The aim of this study was to examine the efficacy and safety of a commonly used NSAID, naproxen. We hypothesized that naproxen would reduce postoperative pain following CABG without increasing complications. METHODS: Patients (N=98) undergoing primary CABG were randomized to receive naproxen (500 mg q12hX5 doses via suppository started 1h after operation, followed by oral 250 mg q8hX6 doses) or placebo. Standard analgesic and anti-emetic regimens were available to both patient groups. Interventions were double-blinded. Primary end-points were postoperative pain measured before and after chest physiotherapy by visual analog scale and pulmonary slow vital capacity (SVC). RESULTS: Baseline characteristics were equivalent between the two groups. Over the first 4 postoperative days, naproxen decreased pain by 47+/-17% on average before chest physiotherapy (P=0.034), and 44+/-13% after chest physiotherapy (P=0.0092). Patients who received naproxen also had better preservation of SVC over the first 4 postoperative days (mean loss of SVC from baseline: 2.1+/-0.1 vs. 2.5+/-0.1l, naproxen vs. placebo, P=0.0032). This was concomitant with a lower white blood cell count observed in naproxen patients (9.2+/-0.3 vs. 12.7+/-1.5x10(9)/l, naproxen vs. placebo, P=0.03). Patients who received naproxen had more chest tube drainage after 4h postoperatively, but there was no difference in the incidence or amount of transfusions. There was no difference in medication use, length of stay, or in the incidence of atrial fibrillation, azotemia, and other complications. CONCLUSIONS: Naproxen is an effective and low-cost adjunct for optimization of pain control and lung recovery after CABG. Its use may result in increased chest tube drainage, but no apparent increase in other complications. 相似文献