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61.
This paper aims to contribute to the literature on the relationship between productive and healthy ageing as two key theoretical concepts in contemporary ageing. Specifically, volunteering as a productive activity in later life has been associated with social and health benefits for older people. Evidence from the literature has generally focused on global outcomes, such as mortality and self-rated health, or on measures of psychological well-being. This study explored whether volunteering is protective of an important adverse health outcome in later life, that of fall-related hip fracture, utilising data from a case control study of 387 participants. The results showed that volunteer activity in older age remained significantly protective of hip fracture risk [OR: 0.61 (0.38–0.99)], independent of social and physical activity, social support and health status, supporting the hypothesis of a relationship between the concepts of productive and healthy ageing. Whilst further studies are clearly needed to establish causality, these results suggest that health benefits of volunteering in later life might be more extensive than previous studies have shown.  相似文献   
62.
Facilitation of learning and state dependency with nicotine   总被引:4,自引:0,他引:4  
Two studies of nicotine and memory encoding were carried out using a state-dependent design. The first experiment used cigarettes and involved memory for stimuli that could not be encoded phonemically or semantically. The results of this recognition study show that nicotine was facilitating the input of non-phonemicably encodable and non-semanticably encodable information to storage and that nicotine produced state-dependent learning. The second study used nicotine tablets and involved memory for concrete words. The results of the free recall study show that nicotine produced state-dependent learning, that nicotine was facilitating the input of information to storage, but there was no evidence that associative processes had been changed by nicotine. These findings give no support for the suggestion that a cholinergic system in the brain is controlling the encoding of intrinsic cues relating to phonemic and semantic properties of things but not those involving mnemonic encoding by mental imagery, but rather that the cholinergic system is non-specifically involved in encoding.  相似文献   
63.
Objectives: To develop formal processes for the collection, disclosure, and effective use of accident and emergency (A&E) department derived assault injury data for city violence reduction.

Methods: Over a four year period, managed by a multi-agency steering group, A&E data collection, collation, and disclosure processes were developed, instituted, and refined. Consultations and negotiations between agencies identified the most effective and ethical methods, appropriate recipients, and the nature of the information of most use.

Results: Disclosure of A&E data to city authorities, the police, and local media drew substantial attention and crime prevention resources to the locations of violence. As a result, a police task force responsible for targeting city street crime was funded, which analysed both A&E and police information. Monthly, electronic transfer of raw, anonymous data to the task force crime analyst informed and prompted violence prevention initiatives by several agencies. Police mounted overt and covert interventions targeted at violence hotspot licensed premises and used the data to oppose, on injury grounds, drinks/entertainment licence applications. Transport authorities established new half hourly night time city centre bus services. The local authority mounted an assault awareness campaign in schools and public libraries, and licensing magistrates used the data to measure, for example, the impact of continuous 36 hour drinks licensing on public safety.

Conclusions: The principal finding of this evaluation was that judicious sharing of unique information about locations and times of violence derived from A&E patients was a powerful and effective means of targeting police and other local resource to bring about violence reduction.

  相似文献   
64.
65.
To study the effects of beta-2 agonist on metabolic regulation in fetal lamb lung, ritodrine hydrochloride, a preferential beta-2 agonist, was infused i.v. at a rate of 1.3 +/- 0.4 micrograms/kg/min (mean +/- S.D.) for 24 hr into six twin chronically catheterized fetal lambs starting between 0.86 and 0.91 gestation. Lung glycogen was depleted 56% in the ritodrine-infused twins and glycogen phosphorylase a activity was increased 1.8-fold whereas glycogen synthase activity remained unchanged. Cyclic AMP-dependent protein kinase activity increased 1.7-fold, calcium-calmodulin-dependent protein kinase (phosphorylase kinase) activity increased 1.4-fold and calcium-phospholipid-dependent protein kinase (protein kinase C) activity increased 1.6-fold. In addition, the maximal binding capacity of pulmonary beta receptors decreased 49% in the ritodrine-infused twins. However, lung cyclic AMP content was unchanged after 24 hr of ritodrine infusion. We conclude that beta-2 agonist activates protein kinases, depletes glycogen and reduces the binding capacity of beta receptors in the fetal lamb lung. We speculate that these adrenergic mechanisms are involved in regulating the effects of beta-2 agonist on fetal lung liquid and surfactant production.  相似文献   
66.
67.
Lung development and adult lung diseases   总被引:4,自引:0,他引:4  
Shi W  Bellusci S  Warburton D 《Chest》2007,132(2):651-656
Adult respiratory diseases are caused by many factors, including genetic-environmental interaction. Genetic abnormalities can impact early fetal lung development, postnatal lung maturation, as well as adult lung injury and repair. Studies suggest that abnormally developed lung structure and function may contribute as a susceptibility factor for several adult lung diseases. This review focuses on the relationship between lung development and pathogenesis of several lung diseases including COPD, cystic fibrosis (CF), and asthma. COPD with emphysema has been considered to be an accelerated involutional disease of aging smokers. However, since only a proportion (approximately 15%) of smokers get COPD with emphysema, clearly genetic susceptibility must play a significant part in determining both the age of onset and the rapidity of decline in lung function. In mice, interference with key genes either by null mutation, hypomorphism, or gain or loss of function results in phenotypes comprising either neonatal lethal respiratory distress if the structural effect is severe, or reduced alveolarization and/or early onset emphysema if the effect is milder. Reported susceptibility candidate genes are therefore discussed in some detail, including elastin, lysyl oxidase, fibrillin, the transforming growth factor-beta-Smad3 pathway, as well as extracellular matrix proteases. In the case of CF, the Cftr gene has been shown to regulate fetal lung epithelial cell differentiation and maturation. Subtle abnormalities of lung structure and function are found in clinically asymptomatic CF infants. Finally, airway remodeling due to chronic inflammation is important in infants who later acquire asthma.  相似文献   
68.
Inflammation and ischaemic stroke   总被引:2,自引:0,他引:2  
PURPOSE OF REVIEW: Inflammation is implicated in ischaemic stroke as a general cardiovascular risk factor, a possible immediate trigger, a component (and possible exacerbating factor) of the response to tissue injury, a marker of future risk, and as a therapeutic target. Each aspect is reviewed. RECENT FINDINGS: Evidence of epidemiological association of inflammatory markers, particularly C-reactive protein, has accrued, but the independence of inflammation from more conventional risk indicators is under question. Other inflammatory markers are associated with intermediate phenotypes such as hypertension. Tissue inflammation in atherosclerotic plaque is of probable relevance in identifying recently symptomatic carotid disease. Both humoral and cellular inflammation are evident following stroke, with evidence that these responses may exacerbate tissue injury. Blockade of interleukin-1, or of neutrophil chemotaxis, has reduced infarct volume in models of stroke but has yet to show benefit in clinical trials. Other anti-inflammatory strategies are promising. SUMMARY: Inflammation is implicated in several aspects of acute ischaemic stroke. It remains to be established whether the inflammatory response is a truly independent risk factor in general, or whether specific anti-inflammatory interventions are beneficial either in prevention or acute treatment.  相似文献   
69.
Macrophage presence within atherosclerotic plaque is a feature of instability and a risk factor for plaque rupture and clinical events. Activated macrophages express high levels of the translocator protein/peripheral benzodiazepine receptor (TSPO/PBR). In this study, we investigated the potential for quantifying plaque inflammation by targeting this receptor. TSPO expression and distribution in the plaque were quantified using radioligand binding assays and autoradiography. We show that cultured human macrophages expressed 20 times more TSPO than cultured human vascular smooth muscle cells (VSMCs), the other abundant cell type in plaque. The TSPO ligands [3H](R)-1-(2-chlorophenyl)-N-methyl-(1-methylpropyl)-3-isoquinoline carboxamide ([3H](R)-PK11195) and [3H]N-(2,5-dimethoxybenzyl)-N-(5-fluoro-2-phenoxyphenyl)acetamide ([3H]-DAA1106) bound to the same sites in human carotid atherosclerotic plaques in vitro, and demonstrated significant correlation with macrophage-rich regions. In conclusion, our data indicate that radioisotope-labelled DAA1106 has the potential to quantify the macrophage content of atherosclerotic plaque.  相似文献   
70.
We developed a multivariate prediction equation for estimating the highest obtainable pulmonary oxygen uptake (VO2p) during the 6-minute walk test (6-MWT) in 54 organ transplant recipients: heart/heart-double-lung (n=14), kidney/kidney-pancreas (n=16), liver (n=14), double lung (n=8), bone marrow (n=2). They were of age, 48+/-12 years. Participants performed a 6-MWT during which expired gases were collected and analyzed with a portable metabolic system interfaced with a wireless heart rate monitor. The following variables significantly contributed to the model for predicting the highest obtainable 6-MWT VO2p: 6-MWT distance (m), age (years), gender (male=0, female=1), resting heart rate, peak heart rate, weight (kg), and transplant type (kidney/kidney-pancreas=1, other=0), where: VO2p=1.253+0.022 (6-MWT distance)+0.112 (age) -3.192 (gender) -0.104 (resting heart rate)+0.127 (peak 6-MWT heart rate)-0.084 (weight)+2.116 (transplant type). The explanatory variables in our final model accounted for 78% of the variance in 6-MWT VO2p. In conclusion, the addition of an easily estimated 6-MWT VO2p will provide added clinical information of functional capacity following an exercise rehabilitation intervention or during routine follow-up for organ transplant recipients.  相似文献   
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