全文获取类型
收费全文 | 2115篇 |
免费 | 128篇 |
国内免费 | 42篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 37篇 |
妇产科学 | 35篇 |
基础医学 | 196篇 |
口腔科学 | 13篇 |
临床医学 | 335篇 |
内科学 | 250篇 |
皮肤病学 | 37篇 |
神经病学 | 216篇 |
特种医学 | 119篇 |
外科学 | 176篇 |
综合类 | 258篇 |
一般理论 | 2篇 |
预防医学 | 241篇 |
眼科学 | 32篇 |
药学 | 199篇 |
2篇 | |
中国医学 | 69篇 |
肿瘤学 | 65篇 |
出版年
2024年 | 4篇 |
2023年 | 29篇 |
2022年 | 100篇 |
2021年 | 131篇 |
2020年 | 83篇 |
2019年 | 50篇 |
2018年 | 54篇 |
2017年 | 63篇 |
2016年 | 57篇 |
2015年 | 74篇 |
2014年 | 110篇 |
2013年 | 133篇 |
2012年 | 131篇 |
2011年 | 141篇 |
2010年 | 97篇 |
2009年 | 102篇 |
2008年 | 83篇 |
2007年 | 92篇 |
2006年 | 91篇 |
2005年 | 68篇 |
2004年 | 53篇 |
2003年 | 56篇 |
2002年 | 55篇 |
2001年 | 44篇 |
2000年 | 40篇 |
1999年 | 33篇 |
1998年 | 34篇 |
1997年 | 28篇 |
1996年 | 31篇 |
1995年 | 23篇 |
1994年 | 30篇 |
1993年 | 17篇 |
1992年 | 14篇 |
1991年 | 8篇 |
1990年 | 19篇 |
1989年 | 14篇 |
1988年 | 13篇 |
1987年 | 15篇 |
1986年 | 4篇 |
1985年 | 19篇 |
1984年 | 14篇 |
1983年 | 6篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1972年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有2285条查询结果,搜索用时 15 毫秒
101.
目的利用入院前候床期实施健康教育,以缩短住院时间和提高健康教育效果。方法将120例肺癌手术患者按时间段分为对照组和实验组60例。对照组按常规待患者入院后实施责任制整体护理,实验组于门诊确定住院手术后即建立档案实施健康教育,包括疾病知识、呼吸功能锻炼、手术相关事项告知等,并与入院后的教育相衡接至患者出院。结果实验组术后肺部并发症发生率显著低于对照组、健康知识掌握程度及满意度显著优于对照组、住院时间显著短于对照组(均P0.01)。结论对肺癌手术患者将健康教育提前至候床期间实施,可提高患者健康知识掌握度、有助于降低手术并发症、缩短住院时间及提高患者满意度。 相似文献
102.
目的观察模拟失重效应对下肢肌萎缩的影响及中药红景天的干预作用。方法 16名成年男性健康志愿者随机分为对照组(8人)和用药组(8人),进行45 d-6°头低位卧床模拟长期失重效应实验。卧床期间,用药组和对照组每天分别服用红景天(红益胶囊)和安慰剂。卧床前、中、后动态测量小腿围径;并采用MRI技术,测试和分析卧床前、后大腿和小腿肌群最大横截面积和肌肉体积的变化。结果1)卧床期间用药组和对照组小腿围径进行性下降,在卧床30和45 d均显著下降(P0.01),但用药组下降幅度显著减少(P0.05);2)卧床45 d,用药组和对照组大腿和小腿肌肉最大横截面积均显著降低(P0.01),其中小腿比目鱼肌下降幅度最大。用药组肌肉最大横截面积的减少较对照组均有改善作用(P0.05);3)对照组大腿和小腿肌群肌肉体积在卧床45 d均显著下降(P0.01),以比目鱼肌体积下降最为明显,用药组下降幅度显著减少,且比目鱼肌对抗作用最为明显(P0.01)。结论 45 d-6°头低位卧床引起进行性加重的肌萎缩,中药红景天可部分对抗模拟长期失重效应诱导的下肢肌萎缩。 相似文献
103.
微重力条件下人体体液调节模型的分析与改进思考 总被引:1,自引:0,他引:1
航天和模拟微重力时研究表明:微重力与现有模拟微重力模型时人体生理学变化的主要差异表现在低压区循环和体液、电解质代谢。微重力生理研究的人体模型在进一步了解微重力对人体的生理影响和机理中不可缺少,有必要将现有人体模拟微重力模型加以改进。利用人体不同角度和不同压力制度的立位倾斜(HUT)加下体正压、头低位卧床(HDT)加上体负压,测量心血管参数、体液调节因子、肾排泄的有关指标,与航天中的相应指标对照,筛 相似文献
104.
Zinc transporter 3 (ZnT3) is the sole mechanism responsible for concentrating zinc ions within synaptic vesicles in a subset of the brain’s glutamatergic neurons. This vesicular zinc can then be released into the synaptic cleft in an activity-dependent fashion, where it can exert many signaling functions. This review provides a comprehensive discussion of the localization and function of ZnT3 and vesicular zinc in the central nervous system. We begin by reviewing the fundamentals of zinc homeostasis and transport, and the discovery of ZnT3. We then focus on four main topics. I) The anatomy of the zincergic system, including its development and its modulation through experience-dependent plasticity. II) The role of zinc in intracellular signaling, with a focus on how zinc affects neurotransmitter receptors and synaptic plasticity. III) The behavioural characterization of the ZnT3 KO mouse, which lacks ZnT3 and, therefore, vesicular zinc. IV) The roles of ZnT3 and vesicular zinc in health and disease. 相似文献
105.
Sterrenburg L Gaszner B Boerrigter J Santbergen L Bramini M Roubos EW Peeters BW Kozicz T 《Journal of neuroscience research》2012,90(1):179-192
Male and female rodents respond differently to acute stress. We tested our hypothesis that this sex difference is based on differences in stress sensitivity of forebrain areas, by determining possible effects of a single acute psychogenic stressor (1-hr restraint stress) on neuronal gene expression (c-Fos and FosB immunoreactivities), storage of corticotropin-releasing factor (CRF) immunoreactivity, and CRF production (CRF mRNA in situ hybridization) as well as the expression of genes associated with epigenetic processes (quantitative RT-PCR) in the rat paraventricular nucleus (PVN), the oval and fusiform subdivisions of the bed nucleus of the stria terminalis (BSTov and BSTfu, respectively), and the central amygdala (CeA), in both males and females. Compared with females, male rats responded to the stressor with a stronger rise in corticosterone titer and a stronger increase in neuronal contents of c-Fos, CRF mRNA, and CREB-binding protein mRNA in the PVN. In the BSTov, females but not males showed an increase in c-Fos, whereas the CRF mRNA content was increased in males only. In the BSTfu, males and females showed similar stress-induced increases in c-Fos and FosB, whereas in the CeA, both sexes revealed similar increases in c-Fos and in CRF mRNA. We conclude that male and female rats differ in their reactivity to acute stress with respect to possibly epigenetically mediated (particularly in the PVN) neuronal gene expression and neuropeptide dynamics (PVN and BSTov) and that this difference may contribute to the sex dependence of the animal's physiological and behavioral responses to an acute stressor. 相似文献
106.
《The International journal of neuroscience》2012,122(11):2056-2073
In this study, we established parameters of the soleus H-reflex excitability in response to changes of posture and load in 8 chronic spinal cord injured (SCI) and 10 spinal-intact subjects. The soleus H-reflex recruitment curve was established in all subjects while they were supine, seated, and standing on a stable treadmill. During standing, body weight support (BWS) was provided via an upper body harness and ranged in SCI subjects from 20%–50% and in spinal-intact subjects was set at 0% and 50%. Stimuli corresponding to the H-threshold (Hth), maximal H-reflex amplitude (Hmax), and 50% of Hmax as well as the reflex gain were estimated based on a sigmoid function of the ascending limb of the soleus H-reflex recruitment curve. The soleus H-reflex gain, Hmax amplitude, and stimuli corresponding to Hth, 50% of Hmax, and Hmax were increased in SCI subjects regardless of the body position and loading. Further, the reflex gain was not modulated appropriately during conditions of weight bearing in SCI subjects. Impaired spinal reflex excitability in SCI subjects is accompanied by changes of the H-reflex recruitment curve parameters regardless of presence or absence of body loading. 相似文献
107.
Glucocorticoids mediate plethora of actions throughout the human body. Within the brain, they modulate aspects of immune system and neuroinflammatory processes, interfere with cellular metabolism and viability, interact with systems of neurotransmission and regulate neural rhythms. The influence of glucocorticoids on memory and emotional behaviour is well known and there is increasing evidence for their involvement in many neuropsychiatric pathologies. These effects, which at times can be in opposing directions, depend not only on the concentration of glucocorticoids but also the duration of their presence, the temporal relationship between their fluctuations, the co-influence of other stimuli, and the overall state of brain activity. Moreover, they are region- and cell type-specific. The molecular basis of such diversity of effects lies on the orchestration of the spatiotemporal interplay between glucocorticoid- and mineralocorticoid receptors, and is achieved through complex dynamics, mainly mediated via the circadian and ultradian pattern of glucocorticoid secretion. More sophisticated methodologies are therefore required to better approach the study of these hormones and improve the effectiveness of glucocorticoid-based therapeutics. 相似文献
108.
PER2, a key molecular component of the mammalian circadian clock, is expressed rhythmically in many brain areas and peripheral tissues in mammals. Here we review findings from our work on the nature and regulation of rhythms of expression of PER2 in two anatomically and neurochemically defined subregions of the central extended amygdala, the oval nucleus of the bed nucleus of the stria terminalis (BNSTov) and the central nucleus of the amygdala (CEA). Daily rhythms in the expression of PER2 in these regions are coupled to those of the master circadian pacemaker, the suprachiasmatic nucleus (SCN) but, importantly, they are sensitive to homeostatic perturbations and to hormonal states that directly influence motivated behavior. 相似文献
109.
Sayamwong E. Hammack Ji-Dong Guo Rimi Hazra Joanna Dabrowska Karyn M. Myers Donald G. Rainnie 《Progress in neuro-psychopharmacology & biological psychiatry》2009
Substantial evidence has suggested that the activity of the bed nucleus of the stria terminalis (BNST) mediates many forms of anxiety-like behavior in human and non-human animals. These data have led many investigators to suggest that abnormal processing within this nucleus may underlie anxiety disorders in humans, and effective anxiety treatments may restore normal BNST functioning. Currently some of the most effective treatments for anxiety disorders are drugs that modulate serotonin (5-HT) systems, and several decades of research have suggested that the activation of 5-HT can modulate anxiety-like behavior. Despite these facts, relatively few studies have examined how activity within the BNST is modulated by 5-HT. Here we review our own investigations using in vitro whole-cell patch-clamp electrophysiological methods on brain sections containing the BNST to determine the response of BNST neurons to exogenous 5-HT application. Our data suggest that the response of BNST neurons to 5-HT is complex, displaying both inhibitory and excitatory components, which are mediated by 5-HT1A, 5-HT2A, 5-HT2C and 5-HT7 receptors. Moreover, we have shown that the selective activation of the inhibitory response to 5-HT reduces anxiety-like behavior, and we describe data suggesting that the activation of the excitatory response to 5-HT may be anxiogenic. We propose that in the normal state, the function of 5-HT is to dampen activity within the BNST (and consequent anxiety-like behavior) during exposure to threatening stimuli; however, we suggest that changes in the balance of the function of BNST 5-HT receptor subtypes could alter the response of BNST neurons to favor excitation and produce a pathological state of increased anxiety. 相似文献
110.
Shun Sasagawa Junichi Ushiyama Kei Masani Motoki Kouzaki Hiroaki Kanehisa 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2009,196(4):537-544
Human bipedal stance is often modeled as a single inverted pendulum that pivots at the ankle joints in the sagittal plane. Because the center of body mass is usually maintained in front of the ankle joints, ankle extensor torque is continuously required to prevent the body from falling. During quiet standing, both passive and active mechanisms contribute to generate the ankle extensor torque counteracting gravity. This study aimed to investigate the active stabilization mechanism in more detail. Eight healthy subjects were requested to stand quietly on three different surfaces of 1) toes-up, 2) level, and 3) toes-down. Surface electromyogram (EMG) was recorded from the medial head of the gastrocnemius (MG), soleus (SOL), and tibialis anterior muscles. Inclination angle of the body was simultaneously measured. As a result, we found that EMG activities of MG and SOL were lowest during the toes-up standing and highest during the toes-down, indicating that increased (decreased) passive contribution required less (more) extensor torque generated by active muscle contraction. Frequency domain analysis also revealed that sway-related modulation of the ankle extensor activity (0.12–4.03 Hz) was unchanged among the three foot inclinations. On the other hand, isometric contraction strength of these muscles increased as the slope declined (toes-up < level < toes-down). These results support the idea that by regulating the isometric contraction strength, the CNS maintains a constant level of muscle tone and resultant ankle stiffness irrespective of the passive contribution. Such control scheme would be crucial when we consider the low bandwidth of the intermittent controller. 相似文献