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41.
This two-year intervention program attempted to work with the school as a social unit so that behaviors and attitudes that promote learning could be consistently reinforced throughout the school. Positive changes in anxiety, impulse control, and behavior problems among the students were recorded in the first year but not in the second year. Possible reasons for the failure of the program in the second year and a review of the program by school personnel are reported.  相似文献   
42.
Aims : To ascertain the characteristics of patients whose death was associated with methadone intoxication during the period 1997-9 in the Lothian region of Scotland. Design : Patients were identified from death certificates. General practitioner records relating to methadone-associated deaths were reviewed in association with autopsy, toxicology and police reports. Deprivation categories (DepCat) were derived from the postal code of residence and the Carstairs index. Findings : There were 77 methadone-associated deaths in the Lothian Health Board area. GP records were obtained for 60 patients registered with a general practitioner. The majority of methadone-associated deaths (73%) occurred in persons who were not prescribed methadone at the time of their death. Thirty-eight persons were prescribed medication other than methadone or dihydrocodeine at the time of death. Thirty (79%) of those being prescribed for were receiving benzodiazepines. Forty-seven per cent had a history of excessive alcohol consumption. Fifty per cent had a reported psychiatric history. Sixty per cent had previously attended Accident and Emergency through deliberate self-harm or accidental overdose. Low socioeconomic status was found to be associated with the highest rate of methadone-related deaths. Conclusions : Given the variety of characteristics outlined it is likely that reducing drug-related deaths is a longer term aim, not amenable to one particular solution.  相似文献   
43.
We have investigated the localization of thrombospondin (TSP), fibrinogen, fibronectin, and von Willebrand factor in human platelets by transmission electron microscopy of antibody-stained ultrathin frozen sections. In negatively stained thin sections, alpha granules were identified on the basis of their smooth, roughly spherical shape, size, single limiting electron-lucent 100 A membrane, and frequent presence of electron-dense nucleoid. In contrast, mitochondria exhibited characteristic double membranes and cristae. Sections were separately stained with affinity-purified polyclonal antibodies to these proteins as well as with three monoclonal anti-TSP antibodies. Antibody specificity was documented in radioimmunoassays, by immunofluorescent cross-blocking, and by staining of bands of appropriate mobility in Western blots of whole platelets. Bound antibody was visualized using a 5-nm colloidal gold-avidin conjugate. In resting cells, staining of virtually all alpha granules was observed for all four proteins. In contrast, consistent staining was absent from other organelles, including plasma membranes, mitochondria, and vacuolar structures that may represent the open canalicular system.  相似文献   
44.
Animals placed in complex environments develop greater numbers of visual cortex synapses per neuron than animals housed in standard cages. Increased numbers of synapses could theoretically arise from (i) active formation of new synapses, or (ii) selective stabilization of constitutively produced synapses. The postsynaptic location of polyribosomal aggregates appears to be an indicator of newly forming synapses. In developmental synaptogenesis and adult reactive (to injury) synaptogenesis, polyribosomes are more frequently found at spine synapses and are more likely to appear in the spine head and stem. In the visual cortex of rats from complex environments, there was a greater frequency of spine synapses associated with polyribosomes, relative to rats from individual or group cages. Furthermore, a greater percentage of these spines had polyribosomes in the head and stem region. This suggests that synapses in this region may be actively induced by neural activity arising from the complex environment experience.  相似文献   
45.
Between August 1978 and November 1983, 21 cases of pneumonia caused by Legionella pneumophila occurred in the Leiden University Hospital, mainly among immunocompromised patients. A new serogroup of L. pneumophila, designated serogroup 10 (prototype strain Leiden 1), was isolated from bronchial secretions of four patients, and five patients had serological evidence of infection with this organism. Nine patients had a culture-confirmed infection with L. pneumophila serogroup 1. L. pneumophila serogroups 1 and 10 were also isolated from the hot potable water supply in the building to which 19 of the 21 patients had been admitted. The isolates of L. pneumophila serogroup 1 from patients and the hot potable water were identical in studies with monoclonal antibodies and had the same plasmid profiles. These findings provide further evidence that in our hospital potable water contaminated with L. pneumophila is a source of infection, mainly in immunocompromised patients.  相似文献   
46.
The authors carried out experiments to advance the midface in growing sheep using a distraction force across the zygomaticomaxillary sutures. They wished to assess the possibility of performing distraction osteogenesis across intact sutures as well as distraction after Le Fort osteotomies. Their results demonstrate that the technique of gradual distraction after osteotomy is successful in the growing animal. Bilateral distraction across intact sutures did not advance the midface or change the dental relationship. Unilateral distraction was successful in angulating the midface away from the distracting force in the intact growing animal. Alternating unilateral distraction or "waltzing" was surprisingly effective in advancing the midface in one of the animals studied and may become applicable in some craniofacial deformities. In all intact animals there was some expansion of the zygomaticomaxillary suture as well as a substantial migration of the distraction devices through the bone.  相似文献   
47.
Although iron, vltamm B12, and folate deficiency have been well documented after gastric bypass operations performed for morbid obesity, there is surprisingly little information on either the natural course or the treatment of these deficiencies in Roux-en-Y gastric bypass (RYGB) patients Durmg a l0-year period, a complete blood count and serum levels of iron, total iron-binding capacity, vltamin B12, and folate were obtained in 348 patients preoperatively and postoperatively at 6-month intervals for the first 2 years, then annually thereafter The principal objectives of this study were to determine how readily patients who developed metabolic deficiencies after Roux-en-Y gastric bypass responded to postoperative supplements of the deficient micronutrient and to learn whether the risk of developmg these deficiencies decreases over time Hemoglobin and hematocrit levels were slgnificantly decreased at all postoperative intervals in comparison to preoperative values Moreover, at each successive interval through 5 years, hemoglobin and hematocrit were decreased signifiantly compared to the preceding interval Folate levels were significantly increased compared to preoperative levels at all time intervals Iron and vltamin B12 levels were lower than preoperative measurements and remained relatively stable postoperatively Half of the low hemoglobin levels were not associated with iron deficiency Taking multivltamin supplements resulted in a lower incidence of folate deficiency but did not prevent iron or vitamin B12 deficiency Oral supplementation of iron and vitamin B12 corrected defiaencies in 43% and 81% of cases, respectively Folate deficiency was almost always corrected with multivitamins alone No patient had symptoms that could be attributed to either vitamin B12 or folate deficiency Conversely, many patients had symptoms of iron deficiency and anenua Lack of symptoms of vitamin B12 and folate deficiency suggests that these deficiencies are not clinically important after RYGB Conversely, iron deficiency and anemia are potentially serious problems after RYGB, particularly in younger women Hence we recommend prophylactic oral iron supplements to premenopausal women who undergo RYGB  相似文献   
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50.
Most radiotherapy (RT) involves the use of high doses (>50 Gy) to treat malignant disease. However, low to intermediate doses (approximately 3–50 Gy) can provide effective control of a number of benign conditions, ranging from inflammatory/proliferative disorders (e.g. Dupuytren''s disease, heterotopic ossification, keloid scarring, pigmented villonodular synovitis) to benign tumours (e.g. glomus tumours or juvenile nasopharyngeal angiofibromas). Current use in UK RT departments is very variable. This review identifies those benign diseases for which RT provides good control of symptoms with, for the most part, minimal side effects. However, exposure to radiation has the potential to cause a radiation-induced cancer (RIC) many years after treatment. The evidence for the magnitude of this risk comes from many disparate sources and is constrained by the small number of long-term studies in relevant clinical cohorts. This review considers the types of evidence available, i.e. theoretical models, phantom studies, epidemiological studies, long-term follow-up of cancer patients and those treated for benign disease, although many of the latter data pertain to treatments that are no longer used. Informative studies are summarized and considered in relation to the potential for development of a RIC in a range of key tissues (skin, brain etc.). Overall, the evidence suggests that the risks of cancer following RT for benign disease for currently advised protocols are small, especially in older patients. However, the balance of risk vs benefit needs to be considered in younger adults and especially if RT is being considered in adolescents or children.  相似文献   
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