全文获取类型
收费全文 | 22637篇 |
免费 | 1300篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 254篇 |
儿科学 | 634篇 |
妇产科学 | 418篇 |
基础医学 | 3187篇 |
口腔科学 | 385篇 |
临床医学 | 2152篇 |
内科学 | 4085篇 |
皮肤病学 | 342篇 |
神经病学 | 2643篇 |
特种医学 | 1230篇 |
外国民族医学 | 1篇 |
外科学 | 3402篇 |
综合类 | 195篇 |
一般理论 | 22篇 |
预防医学 | 1584篇 |
眼科学 | 381篇 |
药学 | 1838篇 |
中国医学 | 88篇 |
肿瘤学 | 1155篇 |
出版年
2023年 | 83篇 |
2022年 | 121篇 |
2021年 | 388篇 |
2020年 | 250篇 |
2019年 | 387篇 |
2018年 | 459篇 |
2017年 | 335篇 |
2016年 | 424篇 |
2015年 | 471篇 |
2014年 | 723篇 |
2013年 | 998篇 |
2012年 | 1467篇 |
2011年 | 1562篇 |
2010年 | 890篇 |
2009年 | 856篇 |
2008年 | 1448篇 |
2007年 | 1474篇 |
2006年 | 1414篇 |
2005年 | 1465篇 |
2004年 | 1395篇 |
2003年 | 1340篇 |
2002年 | 1268篇 |
2001年 | 261篇 |
2000年 | 201篇 |
1999年 | 253篇 |
1998年 | 284篇 |
1997年 | 233篇 |
1996年 | 208篇 |
1995年 | 177篇 |
1994年 | 166篇 |
1993年 | 159篇 |
1992年 | 144篇 |
1991年 | 118篇 |
1990年 | 106篇 |
1989年 | 128篇 |
1988年 | 126篇 |
1987年 | 108篇 |
1986年 | 90篇 |
1985年 | 109篇 |
1984年 | 106篇 |
1983年 | 103篇 |
1982年 | 108篇 |
1981年 | 101篇 |
1980年 | 96篇 |
1979年 | 93篇 |
1978年 | 70篇 |
1977年 | 87篇 |
1976年 | 67篇 |
1975年 | 62篇 |
1973年 | 60篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
Thomas Abel William C. Cockerham Guenther Lueschen Gerhard Kunz 《Social science & medicine (1982)》1989,28(12):1269-1274
This paper examines whether American males with a high degree of control over their work situation pursue healthy lifestyles and rate their physical health more positively than those who score low on occupational self-direction. That is, are persons who control their work more likely to also try to control their health through living in a particularly healthy manner? We found that there was no support for a spillover effect from high occupational self-direction to enhanced participation in health lifestyles or more positive self-rated health. The findings suggest health lifestyles have spread throughout occupational work groups in the U.S. and support research that maintains such lifestyles have spread across social strata in America. 相似文献
63.
Frans H. J. Claas Janneke Langerak Lois Lolkes de Beer Jon J. van Rood 《Tissue antigens》1981,17(1):64-66
Preincubation of donor platelets with ticarcillin will prevent the reactivity of a platelet antibody against these platelets, whereas no influence was observed on antisera against HLA, 5A, 5b and ZWa. The implications for the mechanism of drug-induced antibodies with restricted specificity will be discussed. 相似文献
64.
Daniel J. Weisdorf Martin M. Oken Gerhard J. Johnson Robert E. Rydell 《American journal of hematology》1981,11(4):397-402
Twenty-five patients with refractory anemia with excess blasts (RAEB) were studied. Five of these patients showed Auer rods in their myeloblasts, but met other criteria for RAEB. Median survival of the Auer rod-positive group was 14 months (range 2–27) from diagnosis with survival of 7 months after Auer rods were first observed. Median survival for the Auer rod-negative group was 12 months. Two patients developed overt acute leukemia, both from the Auer rod-negative group. The clinical course of Auer rod-positive RAEB, like that of Auer rod-negative RAEB, was one of progressive bone marrow failure complicated by infection, serious bleeding and the development of absolute transfusion requirement. These findings suggest that Auer rod-positive RAEB is a morphologic variant dysmyelopoietic syndrome that may pursue a similar clinical course to Auer rod-negative disease. Formulation of a separate treatment approach for those RAEB patients who possess Auer rods would appear ill advised. 相似文献
65.
66.
In vivo microdialysis and conditioned place preference studies in rats are consistent with abuse potential of tramadol. 总被引:2,自引:0,他引:2
Jon E Sprague Michael Leifheit Jennifer Selken Michael M Milks David H Kinder David E Nichols 《Synapse (New York, N.Y.)》2002,43(2):118-121
The abuse potential of tramadol was investigated using both in vivo microdialysis measures of dopamine (DA) release within the nucleus accumbens (NAc) shell and the conditioned place preference (CPP) paradigm in rats. Tramadol (75 mg/kg, i.p.) induced a statistically significant increase (starting 80 min posttreatment) in DA release within the NAc shell, which was maintained for at least 120 min posttreatment. Tramadol (18.75, 37.5, and 75 mg/kg i.p.) produced a statistically significant CPP, with the effects of the two highest doses comparable to those induced by morphine (5 mg/kg, s.c.). The release of DA within the NAc shell may be responsible for the rewarding properties of tramadol and, together with the CPP results, provide evidence that tramadol may possess greater abuse potential than originally believed. 相似文献
67.
Mario Leclerc Francisco Martinez Diaz Gerhard Wegner 《Macromolecular chemistry and physics.》1989,190(12):3105-3116
Poly(3-hexylthiophene) (PT6), poly(3-octylthiophene) (PT8), poly(3-decylthiophene) (PT10) and poly(3-dodecylthiophene) (PT12) were synthesized by electrochemical and chemical polymerization. Investigation of these polymers by means of gel permeation chromatography indicates that the polymers prepared from the different monomers under similar conditions do not differ substantially considering molecular weight and molecular weight distribution. Bimodal distributions were found for electropolymerized polymers, and with increasing polymerization time, the high-molecular-weight and probably highly branched fraction increased relatively to the low-molecular-weight fraction. The microstructure of the polymers was investigated by nuclear magnetic resonance, and it has been found that the polymers exhibit more types of structural units than expected from a simple coupling of adjacent thiophene moieties in 2,5′-positions. Chemical oxidation with iron trichloride in chloroform gave soluble, high-molecular-weight poly(3-alkyl-thiophene)s with a rather low amount of irregular couplings, and these more regular polymers exhibited a higher degree of crytallinity. Room temperature conductivities of the oxidized polymers were between 0,1 and 30 S/cm depending on the polymerization conditions, but these values were rather independent of the length of the alkyl substituent. 相似文献
68.
HLA-DR7 predicts the response to alkylating agents in steroid-sensitive nephrotic syndrome 总被引:2,自引:0,他引:2
Martin Konrad Joannis Mytilineos Hans Ruder Gerhard Opelz Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(1):16-19
There is a lack of reliable predictors of the response to alkylating agents in children with idiopathic nephrotic syndrome
(NS). HLA-DR7 is strongly associated with the frequency of relapses in steroid-sensitive NS before cytostatic therapy. We
therefore examined retrospectively the time to the first relapse and the incidence of subsequent relapses in 54 HLA-typed
children with frequently relapsing NS, after treatment with cyclophosphamide (n = 49) or chlorambucil (n = 5) for 8 or 12 weeks; 38 patients were HLA-DR7 positive and 16 negative with 80% in both groups being steroid dependent.
HLA typing was performed using serological or DNA typing methods. Renal biopsy showed minimal glomerular changes. A lower
proportion of HLA-DR7 positive than negative patients remained in remission after 3 years (36% vs. 81%, P<0.02) and 5 years (36% vs. 72%, P<0.03). In the first 3 years after cytostatic therapy the mean number of prednisone-treated relapses was 1.3/patient per year
in HLA-DR7-positive patients compared with 0.4 in negative patients (P<0.025). There was no statistically significant difference in the proportion of relapse-free patients with and without steroid
dependency. The HLA status predicts the response of NS patients to alkylating agents better than the rate of previous relapses.
Received September 19, 1995; received in revised form and accepted April 16, 1996 相似文献
69.
D. Caroline Blanchard Jon K. Shepherd R. J. Rodgers Robert J. Blanchard 《Psychopharmacology》1992,106(4):531-539
The Proxemics/Activity test and the Eat/Drink test, two components of the Anxiety/Defense Test Battery, were developed to measure defensive reactions to situations associated with a natural predator (cat). In the present studies the behavioral effects of 8-OH-DPAT treatment (0.01–1.0 mg/kg, SC) were entirely consistent with anxiety/fear reduction. These effects included an increase in time spent near the cat compartment, and a complimentary decrease in time spent farthest from this compartment, together with an increase in transits and locomote behavior. 8-OH-DPAT (1.0 mg/kg) also increased eat frequencies and durations (highly preferred food) both during and following cat presentation, without influencing drinking. This finding is discussed with reference to previous findings with 8-OH-DPAT in studies assessing both food intake and anxiolysis. Interestingly, 8-OH-DPAT was more potent in a majority of its effects in female subjects, a finding consistent with recent neurochemical data. These findings provide important behavioral evidence for a sexual differentiation in 5-HT function, and support the case for greater emphasis on female subjects in animal models of anxiety.Supported by NIH MH42803 and RCMI Grants RR03061 and RR01825 相似文献
70.
Traumatic anterior shoulder instability has been shown to be associated with a spectrum of capsulolabral pathology, including separation of the labrum (Bankart lesion), capsular rupture, and humeral avulsion of the glenohumeral ligaments (HAGL lesion). We describe a case of combined Bankart and HAGL lesions, a condition that has not been described before. Careful anatomic repair of both components of this bipolar capsular injury resulted in an excellent outcome. 相似文献