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101.
OBJECTIVES: To investigate the contribution of exposure to asbestos through different routes in the development of mesothelioma. METHODS: Case-control study. 185 confirmed cases of mesothelioma and 160 controls were identified, when death had occurred between 1979 and 1991 in four health districts in Yorkshire. The surviving relatives were interviewed to ascertain lifetime exposure to asbestos. Adjusted odds ratios (ORs) of exposure to asbestos (through occupational, paraoccupational, and residential routes) were calculated for cases and were compared with controls. RESULTS: Likely or possible occupational exposure to asbestos was more common in cases than in controls (OR 5.6, 95% confidence interval (95% CI) 3.1 to 10.1). After excluding those with likely or possible occupational exposure, likely or possible paraoccupational exposure was more common in cases than controls (OR 5.8, 95% CI 1.8 to 19.2). Only six cases of mesothelioma were identified as being solely exposed to asbestos through their residence, compared with nine controls. The OR for residential exposure to asbestos varied between 1.5 and 6.6, depending on which potential industrial sources were included, but the 95% CIs were so wide that slightly reduced or greatly increased odds comparing cases with controls could not be excluded. CONCLUSION: Study results support previous evidence that occupational and paraoccupational exposure to asbestos is associated with developing mesothelioma. Despite a rigorous search, purely residential exposure seemed to account for only 3% of identified cases. No firm conclusion can be drawn about the risks from residential exposure alone, as many of the study subjects could also have been occupationally or paraoccupationally exposed to asbestos.  相似文献   
102.
A 28-year-old man with a biopsy-proven benign intraorbital optic nerve sheath meningioma developed recurrent clinical manifestations of ipsilateral retrobulbar inflammation 9 years after undergoing postoperative radiation therapy. Debulking of the tumor 11 years after the original surgery again revealed no pathologic signs of inflammation. Whether growth of tumor, surgery, radiation, or edema triggered the inflammatory manifestations is unclear. Our case affirms that primary optic nerve meningiomas may rarely cause episodic manifestations resembling those of idiopathic orbital inflammation that resolve with corticosteroid treatment.  相似文献   
103.
The costs and quality of four different service models for 40 adults with multiple disabilities were compared. The four service models were: specialised institution-based units; a specialised, campus-style, further education service; specialised community-based group homes; and “ordinary” community-based group homes. Some information was also available from five adults with multiple disabilities living in traditional institutions for people with mental retardation. On almost all measures of service outcome the specialised group-home model was the “preferred” service model, although this model was not associated with particularly high service costs. There was, however, considerable variation in quality within, as well as between, service models, with some residents in all service models experiencing levels of support and engagement similar to those found in traditional institutions. The results of the study are discussed in relation to notions of typical practice and normative standards. The implications of the findings are discussed.  相似文献   
104.
一种简捷可靠的小鼠气管插管新方法   总被引:1,自引:0,他引:1  
目的探索一种安全、高效的小鼠气管插管新方法。方法这种新方法是在小鼠颈前作一小切口,显露气管后,经口腔作气管内插管,费时仅约1 m in。结果经过1300多次实验,无一例失败,成功率达100%。结论这种简捷实用、安全可靠的小鼠气管插管新方法无需特殊设备及体位,一人操作即能完成,可显著提高以小鼠为实验动物模型的成功率。  相似文献   
105.
Background Previous studies have attempted to apply Weiner's attributional model of helping behaviour to care staff who work with service users with intellectual disabilities and challenging behaviours by using studies based on vignettes. The aims of the current study were to investigate the application of Weiner's model to ‘real’ service users with intellectual disabilities and challenging behaviours and to observe the care staff's actual responses to challenging behaviours displayed by service users. Also, to compare care staff attributions, emotions, optimism, willingness to help and observed helping behaviours for self‐injurious behaviours in comparison to other forms of challenging behaviours. Method A total of 27 care staff completed two sets of measures, one set regarding a self‐injurious behaviour and the other regarding other forms of challenging behaviour. An additional 16 staff completed one set of measures. The measures focused on care staff attributions, emotions, optimism and willingness to help. Also, 16 of the care staff were observed interacting with the service users to collect data regarding their responses to challenging behaviours. Results For both self‐injurious behaviours and other forms of challenging behaviour, associations were found between the care staff internal, stable and uncontrollable attribution scores and care staff negative emotion scores. However, no associations were found between the care staff levels of emotion, optimism and willingness to help. Some associations were found between the care staff levels of willingness to help and observed helping behaviours. There were significant differences between the care staff attribution scores with higher scores being obtained for uncontrollable and stable attributions for other forms of challenging behaviours. No significant differences were found between the care staff emotions, optimism, willingness to help and observed helping behaviours. Conclusions The results did not provide support for Weiner's attributional model of helping behaviour. However, a preliminary model of negative care staff behaviour was derived from the exploratory analyses completed. This model proposes that there are associations between internal, stable and uncontrollable attributions and negative emotions in care staff and also between negative emotions and negative behaviours displayed by care staff in response to the actions of service users.  相似文献   
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108.
As the proportion of elderly persons in the population increases, physicians will more frequently see patients with the oral lesions that commonly occur in this group. Periodontal disease represents the most common cause of tooth loss in the elderly. Dentures can create several problems, including traumatic ulceration, denture stomatitis, inflammatory papillary hyperplasia and epulis fissurata. Erythroplakia, rather than leukoplakia, is the most common precursor of oral carcinoma in elderly persons.  相似文献   
109.
The magnocellular neurosecretory cells of the supraoptic nucleus increase production and secretion of oxytocin and/or vasopressin in response to dehydration, gestation and lactation. Dynamic neuronal/glial interactions have also been shown to occur in response to these stimuli, resulting in a reversible increase in soma-somatic direct membrane apposition at these times. Chronic (lactation, 10 days of saline drinking) but not acute stimuli (4–24 h water deprivation) are further accompanied by the reversible formation of axo-somatic double synapses (one presynaptic terminal contacting two postsynaptic elements), which are virtually absent in control animals. The dendrites of these cells course ventrolaterally toward the ventral glial lamina, and have also been shown to be involved in this plasticity: dendro-dendritic direct membrane apposition and axo-somatic double synapses significantly vary with gestation and parturition. The present study investigated the dendritic zone response to both chronic and acute dehydration and rehydration. Increased dendro-dendritic membrane contacts resulted from both stimuli. Rehydration following acute dehydration resulted in a dose-dependent return to control levels, while rehydrated chronic dehydrates did not show such a return until 35 days of rehydration. The percentage of dendrites contacted by double synapses did not vary with treatment, and there were no sex differences. The recalcitrance on the part of the dendrites to return to normal following chronic dehydration may reflect a readiness to respond to renewed hormone demand.  相似文献   
110.
The nucleus circularis, in the anterior hypothalamus, is a group of magnocellular elements arranged in a ring around a capillary bed. The cells are predominantly monopolar, tightly packed, and are flattened at the outer border of the ring. The entire nucleus is surrounded or encapsulated by myelinated fibers. Electrical stimulation of this nucleus produced a short-latency, long-lasting and substantial antidiuresis in ethanol anesthetized rats. Water deprivation induced changes in numbers of nucleoli and cell size increases in these cells. The multiplication of nucleoli in this nucleus during water deprivation was more profound than that previously observed in the supraoptic nucleus. Decreases in multiple nucleoli accompanied voluntary rehydration. Seven criteria for status as an osmoreceptor are listed and the nucleus circularis was found to meet 6 of these criteria, the seventh being the demonstration of receptor potentials which has not yet been attempted.  相似文献   
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