全文获取类型
收费全文 | 32329篇 |
免费 | 3003篇 |
国内免费 | 125篇 |
专业分类
耳鼻咽喉 | 328篇 |
儿科学 | 1062篇 |
妇产科学 | 635篇 |
基础医学 | 4559篇 |
口腔科学 | 410篇 |
临床医学 | 3894篇 |
内科学 | 7036篇 |
皮肤病学 | 761篇 |
神经病学 | 3438篇 |
特种医学 | 1046篇 |
外国民族医学 | 1篇 |
外科学 | 4704篇 |
综合类 | 240篇 |
一般理论 | 29篇 |
预防医学 | 2758篇 |
眼科学 | 392篇 |
药学 | 1880篇 |
中国医学 | 65篇 |
肿瘤学 | 2219篇 |
出版年
2023年 | 113篇 |
2022年 | 234篇 |
2021年 | 552篇 |
2020年 | 478篇 |
2019年 | 862篇 |
2018年 | 969篇 |
2017年 | 805篇 |
2016年 | 809篇 |
2015年 | 1008篇 |
2014年 | 1222篇 |
2013年 | 1708篇 |
2012年 | 1999篇 |
2011年 | 2203篇 |
2010年 | 1410篇 |
2009年 | 1299篇 |
2008年 | 1915篇 |
2007年 | 1991篇 |
2006年 | 1931篇 |
2005年 | 1996篇 |
2004年 | 1926篇 |
2003年 | 1943篇 |
2002年 | 1997篇 |
2001年 | 323篇 |
2000年 | 261篇 |
1999年 | 332篇 |
1998年 | 395篇 |
1997年 | 367篇 |
1996年 | 292篇 |
1995年 | 333篇 |
1994年 | 271篇 |
1993年 | 258篇 |
1992年 | 181篇 |
1991年 | 194篇 |
1990年 | 168篇 |
1989年 | 140篇 |
1988年 | 152篇 |
1987年 | 162篇 |
1986年 | 145篇 |
1985年 | 141篇 |
1984年 | 152篇 |
1983年 | 120篇 |
1982年 | 175篇 |
1981年 | 172篇 |
1980年 | 155篇 |
1979年 | 98篇 |
1978年 | 103篇 |
1977年 | 94篇 |
1976年 | 74篇 |
1975年 | 65篇 |
1972年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
The purpose of this cross-sectional study was to determine whether measures on a selected groups of visual and psychomotor variables distinguished between groups of elite, intermediate and novice table tennis players. The variables included commonly of Melbourne measured clinical functions such as static visual acuity, extent of visual field and oculomotor balance and more experimental visual tasks such as recognition of, peripheral targets, saccadic latency and dynamic visual acuity. Psychomotor performance was assessed by measures of simple reaction time, choice response time and hand movement time. Although elite level competitors had significantly better dynamic visual acuity, a wider visual field and superior recognition of peripheral targets compared to less skilled competitors, the magnitude, or practical significance of these differences was not great and individually accounted for less than 5 per cent of population variance. Elite competitors had significantly faster psychomotor responses than novice players with die skill variables individually accounting for between 21 per cent and 62 per cent of population variance in psychomotor performance. These results indicate that the psychomotor parameters could be a useful part of a test battery for talent identification amongst table tennis players. 相似文献
82.
83.
Weeranuj Yamreudeewong Pharm.D. James V. Johnson M.D. Thomas G. Cassidy M.D. Jean T. Berg R.N. 《Pharmacotherapy》1996,16(6):1159-1165
Warfarin is a commonly used oral anticoagulant that is usually initiated after the definitive diagnosis of a certain thromboembolic disorder or disease. Warfarin therapy will usually be prescribed for 6–12 weeks or more, and some patients may continue therapy throughout life, depending on the type of thromboembolic disorder. Major problems associated with warfarin therapy include adverse effects such as bleeding complications and drug-drug or drug-food interactions. In addition, thromboembolic complications may occur due to subtherapeutic dosages of warfarin. The laboratory reference standards for monitoring warfarin therapy are the prothrombin time (PT) and the International Normalized Ratio (INR). While both the PT or INR will reflect the clinical response in the patient, results reported as INR values have been shown to be more accurate than those reported as PT values. Thirty-two patients were enrolled in this study. Our objectives were to compare INR values measured by both the Coumatrak and conventional laboratory method, and to demonstrate the effects of pharmacist intervention on managing patients receiving warfarin therapy. Results from our study reveal that INR monitoring by Coumatrak is similar to the conventional laboratory method. In addition, our study indicates that patients receiving warfarin therapy can be monitored and managed effectively by pharmacists. 相似文献
84.
Aneurysm of the abdominal aorta in an eighteen-month-old child 总被引:1,自引:0,他引:1
Jean Olivier Defraigne MD Jean Pierre Paquot MD Etienne Creemers MD Raymond MD Limet 《Annals of vascular surgery》1988,2(2):193-195
We report the case of an infected aneurysm of the abdominal aorta in a 18 month-old child, discovered by routine palpation of the abdomen during hospitalization for pneumonia. Ultrasonography and arteriography showed a 6 cm aneurysm of the abdominal aorta beginning distal to the renal arteries which occluded the right common Iliac artery. The aneurysm was treated by interposing a 6 mm Gore-Tex graft between the infrarenal aorta and the aortic bifurcation. Pathologic examination of the aneurysmal wall demonstrated a leukocytic Infiltrate and the presence of encapsulated Gram positive organisms. Arterial aneurysms are exceedingly rare in children. Their etiology is varied: infection, connective tissue disease, trauma, inflammatory arterial disease or other rare diseases such as tuberous sclerosis, neurofibromatosis, or Beçhet’s disease. 相似文献
85.
Mohammad Nasri-Sebdani Flavien Traoré Christian Cognard Daniel Potreau Jean -Pierre Poindessault Guy Raymond 《Pflügers Archiv : European journal of physiology》1990,416(1-2):106-112
The effects of tetracaine (10–50 M) and ryanodine (0.1–10 M) were tested on the slow outward K+ current (I
so) and the mechanical tension of isolated frog muscle fibres in a voltage-clamp device (double mannitol-gap) connected to a mechanoelectric transducer. In the concentration range tested, both drugs induced a simultaneous inhibition of tension and current. In all cases the effect on tension was twice that on current. The tetracaine-induced current and tension blocks were fully reversible and dose-dependent. In contrast the ryanodine effects on current and tension were not reversible and did not exhibit a dose dependence except for the delay before the onset of the response, which was shortened when the concentration was raised. Linear regression analysis of the time-dependent and dose-dependent effects of both drugs indicated a strong correlation between the decreases in tension and current. It is concluded that the slow outward current is partly under the control of the Ca2+ release from sarcoplasmic reticulum during contraction. 相似文献
86.
Ginette Thomas Dominique Pépin Claude Loriette Michel Vidal Marcel Apparu Sabine Coornaert Jean Chambaz Gilbert Béréziat 《European journal of nuclear medicine and molecular imaging》1989,15(7):367-372
The metabolic fate of methyl-branched iodo fatty acids was studied in primary culture of rat hepatocytes. We compared 16-iodo-2-R,S-methyl palmitic acid (2-Me), which can be oxidized, with 16-iodo-3-R,S-methyl palmitic acid (3-Me) which can be oxidized only after an initial oxydation and with 16-iodo-2,2-dimethyl palmitic acid (2,2-Me2) and 16-iodo-3,3-dimethyl palmitic acid (3,3-Me2) which cannot be oxidized at all. The normal fate of natural fatty acids was given by comparative experiments with [1-14C] palmitic acid. Monomethyl-branched iodo fatty acids were taken up in the same range as palmitic acid but more than dimethyl-branched iodo fatty acids. After a 15-h incubation, acido-soluble products (ASP) accounted for 75% of the radioactivity taken up as 16-iodo-2-methyl palmitic acid, 50% as other methyl-branched iodo fatty acids and only 30% as palmitic acid, which indicated that all the methyl-branched iodo fatty acids underwent a strong deiodination process. Fatty acids were esterified in the following order: palmitic acid >16-iodo-3-R,S-methyl palmitic acid>16-iodo-2-R,S-methyl palmitic acid>16-iodo-2,2-dimethyl palmitic acid>16-iodo-3,3-dimethyl palmitic acid. Cultured hepatocytes, labelled for 3 h with the various fatty acids and reincubated for 12 h without fatty acid, secreted large amounts of free dimethylbranched iodo fatty acids as compared to the monomethyl ones and palmitic acid. Only hepatocytes prelabelled with 16-[125I]iodo-2,2-dimethyl palmitic acid exhibited an appreciable secretion of labeled triglycerides, but at a lower rate than with [1-14C] palmitic acid. Conversely, the 16-iodo-monomethyl palmitic acids remained chiefly in hepatocyte triglycerides. Minute amounts of 16-iodo-methyl-branched-palmitic acids were found in hepatocyte or secred phospholipids as compared with palmitic acid. This metabolic fate of methyl-branched iodo palmitic acids argues against their utilization as imaging probes to monitor in vivo the synthesis and the secretion of triglycerides by the liver. 相似文献
87.
Yves de Roten Mlanie Fischer Martin Drapeau Vronique Beretta Ueli Kramer Nathalie Favre Jean‐Nicolas Despland 《Clinical psychology & psychotherapy》2004,11(5):324-331
Early therapeutic alliance is usually measured by the rating of a single session (between the third and the fifth sessions). However, there is a strong argument in favor of viewing early alliance as a developing process. This study examined the relationship between patient's rating of the helping alliance (HAq) at each session and therapy outcome. This comparison was repeated using patterns of alliance over the course of treatment. Patterns of therapeutic alliance development were detected by clustering ratings of a sample of N = 70 outpatients across four sessions of very brief psychotherapeutic intervention. Cluster analysis revealed two main patterns (shapes) of alliance development: (i) stable alliance, and (ii) linear growth pattern. These patterns are more predictive of symptom improvement and social adjustment than single ratings, whereas single ratings measuring the strength of alliance are more correlated with patient's satisfaction. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
88.
Lai J Gouldstone A Butler JP Federspiel WJ Loring SH 《Respiratory physiology & neurobiology》2002,131(3):233-243
The pleural space is modeled in two dimensions as a thin layer of fluid separating a deformable membrane and a rigid surface containing a bump. We computed the steady-state membrane configuration and fluid pressure distribution during relative sliding of the two surfaces. For physiologically relevant values of membrane tension, shear flow-induced pressures near the bump and far-field pressure gradients are similar to those measured in vivo within the pleural space (e.g. Lai-Fook et al.) [J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 56 (1984) 1633-1639]. Deformation of the membrane over the bump suggests that the pressure field generated by the sliding motion promotes an even layer of fluid in the pleural space, preventing asperities from touching. Results also suggest a possible mechanism for pleural fluid redistribution during breathing, whereby irreversible fluid motion is associated with the deformability of the membrane. 相似文献
89.
Résumé La moelle épinière utilise deux grandes modalités fonctionnelles: l'activité réflexe et l'activité programmée.L'activité réflexe constitute la modalité la plus anciennement connue, elle englobe de nombreux arcs réflexes imprégnés de finalités fort diverses. Ainsi le réflexe myotatique, arc monosynaptique le plus simple, maintient et protège le tonus musculaire; les réflexes à point de départ cutané, polysynaptiques, impliquant des réseaux interneuronaux, extériorisent des réponses motrices de défense et de protection indiquant déjà une compétence plus intégrative.L'activité programmée médullaire est supportée par des circuits neuronaux assez solidement fixés. Cette organisation fonctionnelle produit des séquences motrices correctement agencées dans l'espace et dans le temps (locomotion, miction, défécation, réflexes sexuels).Aces deux modalités basales viennent se superposer les influences supra-spinales à capacité exécutoire. Ces signaux, canalisés vers la voie finale commune, agissent, dans une faible part, directement sur les motoneurones spinaux et, en effet, dans une très large mesure, ils utilisent les circuits interneuronaux et modulent ou déclenchent réflexes et programmes médullaires engendrant ainsi une activité cinétique cohérente. 相似文献
90.