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31.
Traditional models of physical dependence suggest that nicotine dependence should be reflected by the extent of drug exposure (e.g., smoking rate) and by evidence of physiological adaptation (e.g., withdrawal severity). An affective model suggests that nicotine dependence should be related to an individual's tendency to experience negative affect and expectations that nicotine use would ameliorate such affect. This research investigated the ability of these 2 models to predict relapse back to smoking at 6 months postquit. Logistic regression models were developed and tested in 505 heavy smokers participating in nicotine patch clinical trials. Results supported both models, but the most potent predictor of outcome was postquit negative affect, which accounted for much of the predictive validity of traditional measures of nicotine dependence. Affective reactivity appears to be a core constituent of dependence.  相似文献   
32.
OBJECTIVES: This study examined hospital preparedness for incidents involving chemical or biological weapons. METHODS: By using a questionnaire survey of 224 hospital emergency departments in 4 northwestern states, we examined administrative plans, training, physical resources, and representative medication inventories. RESULTS: Responses were received from 186 emergency departments (83%). Fewer than 20% of respondent hospitals had plans for biological or chemical weapons incidents. About half (45%) had an indoor or outdoor decontamination unit with isolated ventilation, shower, and water containment systems, but only 12% had 1 or more self-contained breathing apparatuses or supplied air-line respirators. Only 6% had the minimum recommended physical resources for a hypothetical sarin incident. Of the hospitals providing quantitative answers about medication inventories, 64% reported sufficient ciprofloxacin or doxycycline for 50 hypothetical anthrax victims, and only 29% reported sufficient atropine for 50 hypothetical sarin victims (none had enough pralidoxime). CONCLUSIONS: Hospital emergency departments generally are not prepared in an organized fashion to treat victims of chemical or biological terrorism. The planned federal efforts to improve domestic preparedness will require substantial additional resources at the local level to be truly effective.  相似文献   
33.
Functional and structural abnormalities in the thalamus as well as a generalized phospholipid membrane disorder have been implicated in the pathogenesis of schizophrenic psychosis. To determine whether thalamic neuronal abnormalities and altered membrane-associated metabolites can be detected in schizophrenic patients, we used in vivo proton magnetic resonance spectroscopy (1H-MRS) in 32 acutely-ill, medicated schizophrenic patients and 17 age-matched controls. Thalamic and white matter metabolite concentrations (myo-inositol (mI), choline-containing compounds (Cho), total creatine (Cr) and N-acetylaspartate (NAA)) were estimated and corrected for atrophy (CSF) and gray and white matter contributions (GM, WM) by use of image-based voxel segmentation. Thalamic NAA was significantly reduced in schizophrenic patients, whereas Cho and mI were significantly increased in the parietal white matter. White matter Cr was significantly elevated in patients and correlated positively with the brief psychiatric rating scores (BPRS). Regional metabolite levels were inversely associated with GM and WM content reaching significance for mI and Cr in the thalamus and Cho and NAA in the white matter. Reduced NAA in the left thalamus of schizophrenic patients confirms and extends previous spectroscopic data and agrees well with histologic and imaging findings of reduced neuronal density and volume. Elevated Cho in line with 31P-MRS studies suggests increased myelin degradation thus further supporting a generalized membrane disorder in schizophrenic patients. In addition, we demonstrate the need to correct metabolite concentrations for regional tissue composition in studies employing patients with altered brain morphology.  相似文献   
34.
BackgroundRestless legs syndrome (RLS) is a common neurological condition. We investigated the prevalence of RLS in patients suffering from unpleasant sensations in the legs.MethodsWe included 16,543 patients consulting one of 312 primary care practices in Germany on November 8, 2007. All patients filled out a self-assessment questionnaire. Patients who reported suffering from unpleasant sensations in the legs were then assessed by the physician. Main outcome measures were the overall prevalence of unpleasant sensations in the legs and the prevalence of RLS; the most common differential diagnoses in the subpopulation suffered from unpleasant leg sensations.ResultsOut of all participating patients 7704 (46.6%) suffered from unpleasant sensations in the legs and 1758 (10.6%) were diagnosed with RLS according to the four essential clinical criteria. Among patients with unpleasant leg sensations, the prevalence of RLS was considerably higher (22.7%) than in the total population. The most common differential diagnoses were osteoarthritis (21.5%), disc lesion (19.2%), varicose veins (18.8%) and muscle cramps (14.6%). Of the patients with RLS 53.4% had already consulted their physician about their leg problems in the past. Still, only 20.1% of the RLS patients had received the correct diagnosis. Comorbidity rates were significantly increased in RLS patients compared to patients suffering from leg symptoms of other origin.ConclusionsThis study showed a high prevalence of RLS in primary care patients with unpleasant sensations in the legs. Thus, in patients presenting with these symptoms the diagnosis of RLS should routinely be considered.  相似文献   
35.
Black and White smokers may experience aspects of nicotine dependence, including craving, differently. This study used a naturalistic technique, ecological momentary assessment (EMA), to explore differences in craving, mood, expectancy, and smoking enjoyment between Black and White smokers. Participants carried personal digital assistants (PDAs) programmed to obtain multiple daily assessments. Black smokers reported higher craving after smoking and at random assessment times and higher cigarette enjoyment. No differences were found in mood or expectancy. Racial differences in psychological factors related to smoking are explored in the contexts of genetic, sociological, and psychophysiological distinctions. Implications for practice and research are discussed. (Am J Addict 2010;00:1–5)  相似文献   
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This paper reviews the reported experience of operative choledochoscopy. Development of choledochoscopes to the currently available rigid and flexible instruments is described. The collected results of both rigid and flexible choledochoscopy are reported. Retained stones occurred in 97 of 2712 stone-positive explorations with the rigid choledochoscope (3.6 per cent) and in 35 of 1726 stone-positive explorations with the flexible choledochoscope (2.0 per cent). Choledochoscopy should now be a mandatory part of common bile duct exploration.  相似文献   
39.
This review describes pathophysiology of post-surgical hypophosphatemia (HP), which has particularly high incidence following liver transplantation. HP remains poorly understood; and there is a lack of universally accepted guidelines for its investigation and management. The pathogenesis of HP following major liver surgery has been hypothesized as being due either to excessive utilization by regenerating liver or increased urinary losses of phosphate. This review provides evidence that excessive urinary loss rather than increased Pi uptake by the liver is the most likely mechanism, and this may be mediated by recently described phosphaturic factors, known as phosphatonins. Until recently blood Pi homeostasis had been explained solely in terms of classical hormones, i.e., vitamin D and PTH. It is however increasingly recognized that phosphatonins may play a critical role in the post-operative HP, but the exact mechanism and candidate phosphaturic factor has not yet been identified. In this review, we have described likely mechanisms and suggest candidate phosphatonins that may mediate urinary Pi loss following liver transplantation. We also discuss the biochemical consequences of cellular Pi depletion, which exposes some gaps in the utilization of established knowledge and therefore in the management of HP. The main aspects of pathophysiology of HP and cellular Pi depletion are presented to provide rational for novel biochemical investigations, which are likely to improve monitoring of HP associated metabolic stress as well as extent of severity of HP, and thereby enhance management of these patients.  相似文献   
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