全文获取类型
收费全文 | 47913篇 |
免费 | 4012篇 |
国内免费 | 168篇 |
专业分类
耳鼻咽喉 | 499篇 |
儿科学 | 1455篇 |
妇产科学 | 997篇 |
基础医学 | 6538篇 |
口腔科学 | 812篇 |
临床医学 | 5537篇 |
内科学 | 10124篇 |
皮肤病学 | 936篇 |
神经病学 | 5069篇 |
特种医学 | 1547篇 |
外国民族医学 | 6篇 |
外科学 | 7382篇 |
综合类 | 437篇 |
一般理论 | 44篇 |
预防医学 | 4012篇 |
眼科学 | 789篇 |
药学 | 2674篇 |
1篇 | |
中国医学 | 102篇 |
肿瘤学 | 3132篇 |
出版年
2023年 | 172篇 |
2022年 | 362篇 |
2021年 | 799篇 |
2020年 | 634篇 |
2019年 | 1095篇 |
2018年 | 1275篇 |
2017年 | 1027篇 |
2016年 | 1054篇 |
2015年 | 1264篇 |
2014年 | 1602篇 |
2013年 | 2343篇 |
2012年 | 2840篇 |
2011年 | 3145篇 |
2010年 | 2009篇 |
2009年 | 1807篇 |
2008年 | 2792篇 |
2007年 | 2956篇 |
2006年 | 2888篇 |
2005年 | 2923篇 |
2004年 | 2863篇 |
2003年 | 2813篇 |
2002年 | 2839篇 |
2001年 | 505篇 |
2000年 | 410篇 |
1999年 | 523篇 |
1998年 | 566篇 |
1997年 | 536篇 |
1996年 | 425篇 |
1995年 | 469篇 |
1994年 | 390篇 |
1993年 | 363篇 |
1992年 | 321篇 |
1991年 | 325篇 |
1990年 | 281篇 |
1989年 | 244篇 |
1988年 | 245篇 |
1987年 | 264篇 |
1986年 | 241篇 |
1985年 | 243篇 |
1984年 | 281篇 |
1983年 | 237篇 |
1982年 | 308篇 |
1981年 | 293篇 |
1980年 | 285篇 |
1979年 | 186篇 |
1978年 | 185篇 |
1977年 | 177篇 |
1976年 | 164篇 |
1975年 | 137篇 |
1974年 | 129篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Jean Oury 《L'évolution Psychiatrique》2007,72(1):3
The author focuses attention or institutional psychotherapy and draws its clinical, philosophical and also ethical concepts in order to prove that an administrative logic of the mental institutions only leads to loose what characterise healing process. Three main axis are tackled: the concept of reaction, the concept of pathoplasty and the concept of alienation. The concept of reaction makes understandable how the atmosphere of an institution is exercising a so great influence on its patients' symptoms that a self-governing endogenic psychopathological process “that is turned away from its initial cause” is created. That results in the concept of pathoplasty, which refers to the fact that some aspects of the pathology are induced by the institution itself, from which result two main ideas of the institutional psychotherapy: a) an institution is to tie down to an auto analysis to heal its own pathological functioning; b) all the more so that an institution which doesn't could become iatrogenic. The concept of alienation is approached through the historical and philosophical aspects of the Marxist view. The author use Bataille's differentiation between restricted economy “which is in keeping with a capitalist one, susceptible of an accountable evaluation” - and general economy - which confus to negativity as a foundation for an inner social work, apart from any accountable evaluation to Hegel's mind for instance, desire is indissociable from the psychiatric heal. 相似文献
82.
Florent Cachin Janusz Lipiecki Danièle Mestas Aimé Amonchot Benjamin Geissler Cyril Thouly Jean Ponsonnaille Jean Maublant 《Journal of nuclear medicine》2003,44(10):1625-1632
This study validates a new quantitative myocardial perfusion SPECT software. METHODS: The processing starts with the extraction of the morphologic skeleton of the left ventricular myocardium from reconstructed transverse sections. Fuzzy logic is used to decide whether a pixel belongs to the myocardium and any perfusion defect is filled according to a truncated bullet model. The resulting image is partitioned in 18 isovolumetric sectors. Sex-matched normal limits, criteria of abnormality for rest (201)Tl and (99m)Tc-labeled perfusion tracers, reproducibility studies, and detection of coronary artery disease were developed and validated in an overall population of 343 patients. The sex- and tracer-matched means and SDs of a normal response were calculated in 93 male and 93 female patients with a <5% likelihood of coronary artery disease. Reproducibility measurements and assignment of different sectors of the myocardium to a specific coronary were performed from data collected in 49 and 60 patients, respectively. The accuracy of the detection of a coronary artery occlusion was assessed in 48 patients who also underwent coronary angiography. RESULTS: The intra- and interoperator reproducibility of the sectorial activity was high with a linear regression coefficient of 0.97 and a SD of the difference measurement at 4.4% and 3.8%, respectively. Overall sensitivity and specificity for the detection of occluded coronary artery were 90% and 80%, respectively. For the detection of left anterior descending, left circumflex, and right artery coronary occlusion, sensitivity was 92%, 75%, and 92.5%, respectively, and specificity was 75%, 78%, and 90%, respectively. CONCLUSION: The new quantitative myocardial perfusion SPECT software appears to be a very helpful program for the objective analysis of perfusion tracer distribution in myocardial SPECT and a very accurate tool in the detection and localization of coronary artery occlusion. 相似文献
83.
Alain Djacoba Tehindrazanarivelo Jean Marc Visy Marie-Germaine Bousser 《Cephalalgia : an international journal of headache》1992,12(5):318-320
We report two patients with ipsilateral attacks of cluster headache and chronic paroxysmal hemicrania. The first patient, a 33-year-old man, started having attacks of chronic cluster headache at the age of 27. At 33, they were replaced by typical attacks of ipsilateral chronic paroxysmal hemicrania which showed a dramatic improvement with indomethacin 150 mg daily. After two days of complete remission, cluster headache attacks reappeared and persisted until verapamil, 360 mg a day, was added to indomethacin. The second patient, a 45-year-old man, first developed attacks of episodic cluster headache at the age of 35. At 44, he experienced ipsilateral typical attacks of chronic paroxysmal hemicrania, and two months later attacks of cluster headache. Under verapamil 240 mg daily, attacks of cluster headache disappeared, but those of chronic paroxysmal hemicrania increased in frequency until indomethacin 150 mg daily was added. These observations suggest a close relationship but not a similarity between cluster headache and chronic paraoxysmal hemicrania, and show the practical therapeutic interest of maintaining this distinction. 相似文献
84.
85.
86.
Norma Jean Schmieding EdD RN 《Journal of advanced nursing》1987,12(3):357-365
Executive nurse managers, as well as other nurse managers, spend much time responding verbally to people. Whether or not their responses are effective in these situations remains an unexplored area in nursing administration. The author describes a research-based framework to analyse managerial actions. Five types of actions, three non-exploratory and two exploratory, were identified through previous research using Orlando's theory as the framework. Subsequent research suggests nurses prefer that their managers use exploratory action. The article contains discussion on how specific types of actions facilitate or thwart problem identification. 相似文献
87.
Calcium antagonists inhibit positive chronotropic responses to alpha 1-adrenoceptor activation in rat isolated atria 总被引:1,自引:0,他引:1
Positive chronotropic responses of rat isolated atria to phenylephrine were reduced by propranolol (0.3 microM) and the residual response was further depressed by the selective alpha 1-adrenoceptor antagonist prazosin (1 nM) but not yohimbine (10 nM), confirming that a component of the response to phenylephrine was due to activation of alpha 1-adrenoceptors. When beta-adrenoceptors were blocked by propranolol, the positive chronotropic response to phenylephrine was enhanced by increasing the calcium concentration and by the calcium channel activator Bay K 8644 (0.1 microM), whereas the response was decreased by lowering the calcium concentration and by the calcium antagonists verapamil (10 nM), nifedipine (10 nM) and diltiazem (100 nM). In the presence of prazosin, when phenylephrine acts only on beta-adrenoceptors, calcium antagonists had no effect on the response. In rat isolated aortic strips in a calcium-free, high K+ (40 mM) solution, verapamil (10 nM), nifedipine (10 nM) and diltiazem (100 nM) shifted the calcium-induced contraction curves to the right, but prazosin (10 nM) had no effect, indicating that it is not a calcium antagonist. The calcium antagonists in the concentrations stated above had no effect on phenylephrine-induced contractions of rat aortic strips in normal Krebs-Henseleit solution, indicating that they did not block alpha 1-adrenoceptors in these concentrations. Taken together, these data suggest that the positive chronotropic effect of phenylephrine resulting from activation of alpha 1-adrenoceptors involves an increased influx of calcium through channels that are sensitive to organic calcium antagonists. 相似文献
88.
Zvi Bar-Shavit Ronald L. Horst Jean C. Chappel F. Patrick Ross Richard W. Gray Steven L. Teitelbaum M.D. 《Calcified tissue international》1986,39(5):328-333
Summary 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) is a potent inducer of monocytic differentiation of the human promyelocytic leukemia cell line, HL-60. We have noted that
25-hydroxyvitamin D3 (25(OH)D3) in high doses is also capable of promoting monocytic differentiation of this cell line. To test the possibility that the
latter activity is due to conversion of 25OHD3 to 1,25(OH)2D3 by HL-60, we exposed HL-60 cells to 25OHD3 and analyzed the products by HPLC and radioreceptor assay. When chromatographed in the traditional solvent system (isopropanol-hexane),
a new peak appears which migrates with authentic 1,25(OH)2D3. However, in a solvent system containing dichloromethane, 90% of the peak migrates with another metabolite, 19-Nor-10-Keto-25OHD3 (19-Nor-25OHD3). Production of this metabolite is enhanced by living cells and is synthesized by both virgin HL-60 and those which have
undergone differentiation. We next determined if authentic 19-Nor-25OHD3 also promotes differentiation of this cell. As assessed by appearance of the monocyte-specific surface antigen (63D3) and
macrophage-specific esterase activity, we find that this metabolite does, in fact, induce monocytic differentiation of HL-60
with a potency of approximately 1/200 that of 1,25(OH)2D3 and similar to that of 25OHD3. In agreement with the effect upon cell maturation, 19-Nor-25OHD3 displaces3H-1,25(OH)2D3 from its HL-60 receptor with an efficiency comparable to 25OHD3. Hence, HL-60 cells convert 25OHD3 to 19-Nor-25OHD3, and 19-Nor-25OHD3 induces monocytic differentiation of HL-60 with comparable efficiency to its precursor, 25OHD3. 相似文献
89.
90.