全文获取类型
收费全文 | 10927篇 |
免费 | 606篇 |
国内免费 | 147篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 161篇 |
妇产科学 | 92篇 |
基础医学 | 1608篇 |
口腔科学 | 354篇 |
临床医学 | 1268篇 |
内科学 | 1235篇 |
皮肤病学 | 70篇 |
神经病学 | 1402篇 |
特种医学 | 286篇 |
外科学 | 1257篇 |
综合类 | 695篇 |
现状与发展 | 3篇 |
一般理论 | 2篇 |
预防医学 | 1403篇 |
眼科学 | 103篇 |
药学 | 1294篇 |
1篇 | |
中国医学 | 178篇 |
肿瘤学 | 190篇 |
出版年
2024年 | 21篇 |
2023年 | 194篇 |
2022年 | 285篇 |
2021年 | 442篇 |
2020年 | 390篇 |
2019年 | 374篇 |
2018年 | 409篇 |
2017年 | 334篇 |
2016年 | 321篇 |
2015年 | 383篇 |
2014年 | 607篇 |
2013年 | 968篇 |
2012年 | 535篇 |
2011年 | 562篇 |
2010年 | 456篇 |
2009年 | 529篇 |
2008年 | 542篇 |
2007年 | 482篇 |
2006年 | 412篇 |
2005年 | 382篇 |
2004年 | 326篇 |
2003年 | 270篇 |
2002年 | 197篇 |
2001年 | 146篇 |
2000年 | 166篇 |
1999年 | 154篇 |
1998年 | 143篇 |
1997年 | 131篇 |
1996年 | 115篇 |
1995年 | 125篇 |
1994年 | 97篇 |
1993年 | 110篇 |
1992年 | 88篇 |
1991年 | 104篇 |
1990年 | 99篇 |
1989年 | 97篇 |
1988年 | 80篇 |
1987年 | 84篇 |
1986年 | 60篇 |
1985年 | 62篇 |
1984年 | 67篇 |
1983年 | 40篇 |
1982年 | 57篇 |
1981年 | 28篇 |
1980年 | 59篇 |
1979年 | 30篇 |
1978年 | 18篇 |
1977年 | 17篇 |
1975年 | 18篇 |
1973年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
A brief mechanical or electrical stimulus to peripheral nerve afferents from the upper and lower limbs elicited a small and inconsistent EMG response of the orbicularis oculi muscles. This response was facilitated when the stimuli were delivered at fixed leading time intervals, of 45–300 ms, with respect to a supraorbital nerve electrical stimulus. Also, the peripheral nerve stimulus modified the conventional blink reflex responses, inducing facilitation of R1 and inhibition of R2. These results suggest a complex processing of sensory inputs from the face and the limbs at the brainstem, where they are probably integrated in a network of interneurons influencing the excitability of facial motoneurons. 相似文献
13.
P.M. Rossini G. Martino L. Narici A. Pasquarelli M. Peresson V. Pizzella F. Tecchio G. Torrioli G.L. Romani 《Brain research》1994,642(1-2)
Transient rearrangements of finger representation in primary somatosensory cortex induced by an anesthetic block of the sensory information from adjacent fingers have been shown invasively in animals. Such a phenomenon has been now replicated in seven healthy human volunteers. Somatosensory Evoked Fields (SEFs) have been recorded during separate electrical stimulation of the 1st, 3rd, or 5th finger. Recordings were obtained in control conditions (stage A), following complete ischemic anesthesia of the 4 non-stimulated fingers (stage B), and after regaining sensation (stage C). SEFs were recorded using a 28-channel DC-SQUID magnetometer; a single position of the sensor was enough to identify the source of N20m, P30m and following components using the Equivalent Current Dipole (ECD) model. The amount of afferent input during stages A through C was monitored with surface electrodes placed on the nerve at wrist and elbow. No variation of the nerve compound potential was observed during stages A through C. In stage A, the localizing algorithm was able to discriminate the individual finger representation in accordance with the somatotopic organisation of the sensory homunculus. It was observed that the ECDs responsible for the cortical responses from the unanesthetized finger were significantly changing following a relatively brief period of sensory deprivation from the adjacent fingers. Such changes of the ECDs with respect to the control conditions were characterized by an increase in strength and deepening for the middle finger, and by a shift on the coronal plane for the thumb and the little finger (medial for the former, lateral for the latter). Such changes became progressively evident in stage B, but were persisting in stage C. 相似文献
14.
15.
This study uses the Taiwan Healthcare Indicator Series (THIS) system as an example to examine which determinants would improve
performance by sharing indicators from a management perspective. This study population included all 227 hospitals participating
in the THIS system in 2006. A structured questionnaire was sent to the director who was responsible for the THIS system via
electronic mail. A total of 111 responses were returned by February 10, 2006. Questions included current implementation and
impacts of the system. Hierarchical regression models were performed to identify which variables were significantly associated
with performance improvement, adjusted for hospital characteristics. Four variables significantly associated with implementing
the THIS system to improve performance were ‘senior management support,’ ‘benchmarking,’ ‘making departments improve the underperforming
indicators and report the improvement results in performance management meetings,’ and ‘integration with the National Health
Insurance payment regulations’. This study contributes substantially to the evidence base about what works to improve performance
by information sharing. Although information sharing is the basis of efforts to improve performance, senior management support
and how to effectively apply the information are the most important determinants of performance enhancement. 相似文献
16.
Background : In order to find the most useful computerized auditing system for the needs of the QE II Hospital surgical department three surgical auditing software programs were assessed. Methods : The Otago University Surgical Auditing Program, the Australian Surgical Auditing Program, and RACS-Audit were trialled for a period of 1 month each. The software programs were evaluated to find the time requirements for data entry, the level of surgical knowledge needed for effective audit information entry, and the perceived usefulness of the generated reports. Results : It was found that the Otago University program best suited the needs of the department. This system was designed for use in a hospital environment with multiple users. The method of data collection was simple and rapid. Entry of data into the program was logical, well structured and able to be performed by both junior medical staff and clerical staff. Reports generated by this system included information in an appropriate format for the departments' morbidity and mortality meetings. Conclusion : Personal computers are an ideal tool for the undertaking of surgical audit. Software programs are designed for different uses and should be critically assessed to ensure that the method of data entry, the time involved, and the reports generated enable an efficient and effective audit to be carried out. 相似文献
17.
18.
The advent of the small computer as a basic clinical tool will have a significant impact on clinical practice and medical training. The application of probability theory to clinical diagnosis has led to the development of several practical diagnostic programs which run on small computers. Expert systems--interactive programs which function as 'electronic consultants'--have now been successfully developed for a number of clinical situations. Experience with two of these, INTERNIST/CADUCEUS and MYCIN, has provided insight into problems and prospects for expert systems in medicine. Less complex programs, particularly those employing clinical prediction rules, and expert system shells, seem well suited for clinical environments. Although computerized medical diagnosis holds great promise as an aid to clinicians, its success will largely be determined by the quality of the information that clinicians provide for analysis. A brief review of the status of bedside diagnosis reveals that data-gathering strategies and techniques must be better understood. In order to take full advantage of computer programs for diagnosis, basic diagnostic skills must be more heavily emphasized in clinical training. 相似文献
19.
不同剂量瑞芬太尼复合靶控输注异丙酚对心脏瓣膜置换术病人气管插管时血液动力学反应的影响 总被引:1,自引:0,他引:1
目的 评价不同剂量瑞芬太尼复合靶控输注(TCI)异丙酚对心脏瓣膜置换术病人气管插管时血液动力学反应的影响.方法 拟行心脏瓣膜置换术的风湿性心脏病病人30例,随机分为3组(n=10):芬太尼组(Ⅰ组)、小剂量瑞芬太尼组(Ⅱ组)和大剂量瑞芬太尼组(Ⅲ组).麻醉诱导:Ⅰ组静脉注射芬太尼10 μg/kg,然后持续静脉输注芬太尼10 μg·kg-1·h-1;Ⅱ组和Ⅲ组静脉注射瑞芬太尼1μg/kg,然后分别持续静脉输注瑞芬太尼0.5、1.0 μg·kg-1·min-1.3组静脉注射芬太尼或瑞芬太尼后3min开始TCI异丙酚,初始血浆靶浓度为1.0 μg/ml,逐渐递增至2.0 μg/ml.静脉注射罗库溴铵0.6 mg/kg后气管插管.分别在麻醉诱导前(T0)、诱导期间血压最低值时(T1)、插管前即刻(T2)、插管后1 min(T3)、插管后2 min(T4)及插管后5 min(T5)时记录心率(HR)、平均动脉压(MAP)、中心静脉压(CVP)、肺毛细血管楔压(PCWP)、心脏指数(CI)、外周血管阻力指数(SVRI)及左室每搏功指数(LVSWI),并于上述时点测定混合静脉血氧饱和度(S(v)O2).记录诱导期间低血压及气管插管心血管反应的发生情况.结果 3组间麻醉诱导期间低血压及气管插管心血管反应的发生率差异无统计学意义(P>0.05).与T0比较,各组T1,2时HR和MAP均降低,Ⅱ组T3时HR和MAP升高,Ⅲ组T4时MAP降低,Ⅰ组和Ⅱ组T2-4时S(v)O2升高(P<0.05);3组间各时点CVP、PCWP、CI、LVSWI和S(v)O2差异无统计学意义(P>0.05).结论 复合TCI异丙酚(血浆靶浓度2.0 μg/ml)时,静脉注射瑞芬太尼1 μg/kg负荷剂量后,持续静脉输注0.5 μg·kg-1·min-1麻醉诱导时血压和HR下降适度,可较好地抑制心脏瓣膜置换术病人气管插管时血液动力学反应. 相似文献
20.
Cerebellar connections with the motor cortex and the arcuate premotor area: an analysis employing retrograde transneuronal transport of WGA-HRP 总被引:3,自引:0,他引:3
We have employed transneuronal transport to examine the anatomical relationships between the deep cerebellar nuclei and 2 cortical motor areas: the primary motor cortex and the arcuate premotor area (APA). In the same animals, we have also examined the patterns of labeling in the thalamus and the red nucleus to provide evidence for the potential routes of transneuronal transport to the cerebellum. When the appropriate technical procedures were employed, cortical injections of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) resulted in transneuronal labeling within portions of the contralateral deep cerebellar nuclei. Injections into the primary motor cortex labeled neurons in the dentate and in the 2 subdivisions of the interpositus. Injections into the APA labeled neurons in the dentate and in only the posterior subdivision of the interpositus. In most instances, dentate neurons were more intensely labeled following the cortical injections than interpositus neurons. The transneuronal labeling observed in the dentate nucleus was topographically organized. The dentate region that was labeled following injections into the "arm area" of the APA was caudal and ventral to the dentate region that was labeled following injections into the "arm area" of the primary motor cortex. This observation provides evidence for two "arm areas" in the dentate: one anatomically related to the APA, and the other related to the primary motor cortex. More than one route of transport may be responsible for the labeling of cerebellar neurons. We propose that the labeling observed in the dentate nucleus reflects the pattern of connections in the cerebellothalamocortical pathways that link the dentate with the cerebral cortex. Thus, our observations support the concept proposed by Schell and Strick (J. Neurosci. 4:539-560, '84)--that the cortical targets of the dentate nucleus include both the primary motor cortex and the APA. 相似文献