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31.
The arterial baroreflex was studied in subjects who had recently had an episode of vasodepressor syncope. This was determined using 2–3 mcg/kg intravenous boluses of phenylephrine and assessing the bradycardic response. The values were measured in ms/mmHg and expressed as the angular coefficient of the regression line between the increase in R—R interval on the electrocardiograph and the systolic arterial pressure. In subjects examined immediately after the vasodepressor syncope episode the bradycardic response was much more marked than in controls (p < 0.01) and in the subjects themselves 6 months after the episode, provided that they were symptom-free (p < 0.01). It is concluded that in vasodepressor syncope there is a phase in which the baroreflex is highly sensitive and that this is due not to a lowering of the stimulation threshold but to a gain in the efferent arc, which explains a vagotonic response.  相似文献   
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Translation of recommendations on skin cancer prevention formulated by many national and international institutions into efficient steps requires measuring the potential impact in terms of preventable cases. This study analyses the proportion of skin cancers attributable to sun exposure in Turin, Trento and Ragusa. Estimates have been reached by applying the risk models calculated from the case-control study on melanoma in Turin and the Helios multi-centric study on skin carcinomas. The proportion of cases attributable to sun exposure has been subsequently calculated by correcting for the different proportion of skin characteristics among the populations taken into consideration. Attributable risks so calculated show medium to high values for melanoma in Turin (38%) and Trento (29%), while values are lower in Ragusa (17%). As for basal-cell carcinoma, attributable risk values are slightly inferior to those of melanoma. The risk of squamous-cell carcinoma attributable to sun exposure during outdoor work is the highest in Ragusa, with a value of 25%. Taking an annual incidence rate for melanoma of 9 cases per 100,000 inhabitants, and a preventive intervention with 50% of effectiveness, preventable cases should be 2 cases per 100,000 each year. This figure compared with 8 preventable cases of cervix cancer, in a similar population suggests an extremely cautious attitude in taking on programmes aiming to change life styles.  相似文献   
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INTRODUCTION: Behavioral disturbances in patients with Alzheimer's disease (AD) are ill-defined conditions. We hypothesize that the many behavioral disturbances hitherto described and studied might be grouped into few syndromes with separate determinants and correlates. PATIENTS AND METHODS: 162 consecutive patients with probable AD admitted to a dementia unit were assessed by the UCLA Neuropsychiatric Inventory (NPI). RESULTS: Factor analysis was carried out on NPI subscales, leading to three syndromes: 'mood', 'psychotic' and 'frontal'. Patients with the 'psychotic' syndrome were older, had older age at dementia onset, had poorer cognition, were more often males, and had faster rate of dementia progression. Patients with the 'frontal' syndrome had higher education, longer disease duration, and slower rate of progression. DISCUSSION: Some combinations of behavioral disturbances occur more frequently together and might represent separate behavioral syndromes. Different clinical correlates of the syndromes suggest separate etiologies.  相似文献   
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OBJECTIVE: This study measures and compares use of and satisfaction with medical and social services in addition to subjectively perceived needs of family supporters of patients with probable or possible Alzheimer's disease (AD) and family supporters of non-demented elderly people. Differences in judgement of services within the subpopulation of families of AD patients are also assessed by gender and burden level.METHODS: The main family supporters of 60 community-dwelling elderly (aged over 65) with Alzheimer's disease and of 60 age- and sex-matched controls were tested with a detailed questionnaire on use and satisfaction with services, any unmet needs and kinds of intervention perceived to be helpful.RESULTS: Supporters of elderly people with AD were significantly more involved in providing care than supporters of non-demented people. Judgement on the health, social relations and financial status of their families was significantly worse in AD supporters than in supporters of non-demented elderly people. Although the former made more use of available health and social services than the control population, they did appear to make little use of such services, not only because of lack of information but also for logistic reasons or because they would prefer a service with more specifically trained operators or more tailored intervention. AD family supporters would like to receive more information and support from their general practitioner, which confirms the importance of this figure in management of this pathology. They were less satisfied with the care provided than the control population, particularly those with a moderate-high burden. Irrespective of burden level, they also expressed a need for financial and psychological support and adequate intervention schemes, especially within the home. These should be provided by specially trained personnel and be tailored to specifically manage the individual patient's problems, especially in relation to behavioural disorders. This would help alleviate caregiver burden and allow patients to continue to be managed at home.  相似文献   
36.
Record linkage was carried out between the national Registry of AIDS and 13 Cancer Registries (CRs) covering, in 1991, about 15% of the Italian population. Observed and expected numbers of cancers and standardized incidence ratios (SIRs) were assessed in 6067 persons with AIDS, for a total of 25,759 person-years. Significantly increased SIRs were found for Hodgkin''s disease [8.9, 95% confidence interval (CI) 4.4-16.0], in which seven of 11 cases were of mixed cellularity type; invasive carcinoma of the cervix uteri (15.5; 95% CI 4.0-40.1); and non-melanomatous skin cancer (3.0, 95% CI 1.3-5.9), in which five of eight cases were basal cell carcinoma. An excess was also seen for brain tumours, but this may be partly due to misdiagnosis of brain non-Hodgkin''s lymphoma or other brain diseases occurring near the time of the AIDS diagnosis. The risk for all cancer types, after exclusion of Kaposi''s sarcoma (KS) and non-Hodgkin''s lymphoma (NHL), was approximately twice the general population risk. An increased SIR for Hodgkin''s disease in persons with AIDS is thus confirmed, though it is many times smaller than that for NHL. An association with invasive carcinoma of the cervix is also shown at a population level. The excess of non-melanomatous skin cancer seems to be lower than in transplant recipients.  相似文献   
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This article reviews the examination technique of shoulder ultrasound, normal and abnormal ultrasound findings in acute (posttraumatic) and chronic (degenerative) lesions. Moreover, it reviews the effectiveness of ultrasound in relation to magnetic resonance (MR) imaging. Most authors report that full-thickness tears of the supraspinatus can reliably be diagnosed by ultrasound. However, the simple diagnosis of a full-thickness rotator cuff tear is no longer sufficient for surgical management. The precise localization and size of rotator cuff tears as well as the extent of muscle degeneration is important for surgical planning. For this aspect and for partial-thickness tears of the supraspinatus, for subscapularis lesions as well as for lesions of the long biceps tendons there is no consensus regarding the diagnostic value of ultrasound. To the present, ultrasound (contrary to MR imaging) has failed to demonstrate that it consistently influences the clinician's degree of confidence in the clinical diagnosis or the treatment plan. Therefore, some orthopedic surgeons prefer MR imaging to ultrasound in the evaluation of rotator cuff tears and other abnormalities of the glenohumeral joint. Moreover, MR imaging, especially when combined with arthrography, represents a one-step investigation, which not only allows for assessment of rotator cuff lesion but also of lesions of the labrum (Bankart lesions, SLAP lesions), the joint capsule and the biceps tendon. It also demonstrates muscle atrophy, which represents an important predictor of surgical outcome in rotator cuff repair.  相似文献   
38.
Abstract

Behavioral disturbances in Alzheimer's (AD) patients might be caused by environmental factors. The authors tested the hypothesis that delusions in AD might be a result of caregiver's distress. Participants were 22 delusional and 21 nondelusional mild AD patients and their caregivers. Those who cared for nondelusional patients, compared with the delusional patients' caregivers, reported higher levels of distress because of behavioral disturbances other than delusions. When patients were stratified into 2 groups according to median distress value, 64% of the delusional patients and 33% of the nondelusional patients showed a high level of caregiver's distress, X2(1, N = 43) 3.94, p = .047. Although final conclusions about the causal direction of the association cannot be drawn, these findings are consistent with the hypothesis that distressed caregivers might use inappropriate coping strategies that, in turn, might favor the development of delusions.  相似文献   
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