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991.
992.
The effect of normal or sensitized spleen cell transfer from syngeneic euthymic mice to Junin virus-infected suckling athymic mice was studied. Transfer was performed 1 or 7 days after infection. In both cases, an acute lethal disease developed 6-11 days after transfer. The mortality reached 100% in all infected groups receiving normal or sensitized splenocytes, while it was negligible for different control groups of athymic mice. Transfer of normal or sensitized splenocytes was unable to significantly modify brain viral titers, as compared with infected nontransferred athymic mice killed after a 25-day observation period. Brain lesions were demonstrated in about half of the infected athymic mice transferred with sensitized splenocytes and in all euthymic infected mice. These results show that splenocyte transfer from immunocompetent donors is able to change the normal course of persistent Junin virus infection in nude mice to a lethal acute disease, thus pointing to a main role for T cells in its pathogenesis.  相似文献   
993.
994.
Bookstein  JJ 《Radiology》1987,164(1):175-178
The author's experience with 72 patients with impotence, one patient with Peyronie disease (no impotence), and two healthy volunteers indicates that incompetence of the venocclusive mechanism of the corpora cavernosa is probably the most common cause of vasculogenic impotence. Manometric and angiographic studies are the key to diagnosis but only when performed while the venocclusive mechanism is activated. Activation is achieved by intracavernosal injection of a papaverine-phentolamine mixture. Pharmacomanometry, performed with the newly developed pharmacologic maintenance erectile flow (PMEF) method, enabled precise quantitation of the leak at a given cavernosal pressure. A new appreciation of the limited volume of normal flow in the cavernosal arteries indicates that cavernosal leak in the range of only 20 ml/min is probably capable of contributing to impotence. Pharmacocavernosography enabled identification of sites of leakage (key information in the planning of surgical correction) but was unreliable in the evaluation of the severity of leakage.  相似文献   
995.
Sustained attention was studied in 48 children with early treated congenital hypothyroidism and 35 healthy controls, using a computer-paced and a self-paced continuous performance task. The performance of the patients, particularly those in the low T4 group (38 patients with T4 levels < 50 nmol/1 at neonatal screening), declined in the final stage of the computer-paced task, suggesting a problem in remaining attentive over time. The performance of all children declined in the first and improved in the final stage of the self-paced task. This pattern was most pronounced in the low T4 group, reflecting greater variability in their task performance over time, again indicating a problem in sustaining attention. No correlation was found between onset of treatment and sustained attention. The small size of the intermediate T4 group (10 patients with T4 levels ≥ 250 nmol/1 at neonatal screening) made the results more difficult to interpret and may have concealed a problem with sustained attention in this group.  相似文献   
996.
PURPOSE/METHODS: We present the case of a 69 year-old male patient who developed an anterior pole ischemia syndrome in his right eye. He did not have any personal history of diabetes or previous ocular pathology. Indirect ophthalmoscopy did not show any pathological finding. RESULTS/CONCLUSIONS: Carotid Duplex scanning and Nuclear Magnetic Resonance detected a severe carotid stenosis on the same side, which explained the case. We reviewed different forms of presentation of venous stasis syndrome in carotid stenosis and present this uncommon case of anterior segment ischemia syndrome without posterior segment findings.  相似文献   
997.
998.
The authors examined 19 patients with diffuse histiocytic lymphoma of the brain, including 8 with primary disease and 11 with secondary disease. Both primary disease and secondary disease involving the brainstem and deep nuclei exhibited the characteristic CT appearance, consisting of a large, solid, homogeneously enhanced mass with varying amounts of edema. However, most secondary lymphomas outside the brainstem and basal ganglia contained large areas of low attenuation consistent with necrosis. Multifocal lesions were seen only in patients with secondary lymphoma. Systemic chemotherapy for extracranial lymphoma had no effect on the CT appearance of intracranial lesions. The authors suggest that these "unusual" CT patterns are actually typical of a distinct subset of histiocytic lymphomas.  相似文献   
999.
Objective: To determine body composition, coronary risk factors and physical activity and the inter-relationships of these variables in Singaporean school children.
Methodology: This study examined 1681 children (784 boys and 897 girls) from eight primary and seven secondary schools to determine percentiles for body stature and composition, blood pressure, lipids/lipoproteins and blood glucose by gender for three age divisions. An exercise and leisure pursuit questionnaire was administered to ascertain self-reported physical activity patterns. Anthropometric data and blood pressure readings were taken. Capillary blood was drawn from each child via finger prick sampling following an overnight fast. The concentrations of total cholesterol (TCHOL), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and glucose (GLU) were determined from plasma using a dry chemistry analyser. Low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL) and the TCHOL/HDL-C ratio were determined by calculation.
Results: While 47.7% of boys and 22.0% of girls disclosed active lifestyles, differences between the active and non-active children were found in coronary risk factors TCHOL, LDL-C, TG, TCHOL/HDL-C and per cent body fat. No differences were shown between the two groups in HDL-C, GLU and blood pressure. There was a high correlation between the various measures of body composition with the highest correlation ( r =0.806, P < 0.001) found between body mass index (BMI) and waist measurements.
Conclusions: Children in this study who reported no activity or relatively little activity were found to have TCHOL, LDL-C, TG, TCHOL/HDL-C and per cent body fat that were higher than those who reported moderately high or vigorous physical activity patterns.  相似文献   
1000.
Low back pain and disability in 14-year-old schoolchildren   总被引:4,自引:0,他引:4  
In this cross-sectional prevalence study in 1503 14-year-old Finnish schoolchildren (n = 1503) low back pain was found to be the third most common form of pain interfering with schoolwork or leisure time during the past 12 months. The lifetime cumulative incidence of low back pain was 30% and that of sciatica 1.8%. Of the 417 pupils who had experienced low back pain at some time, 39% had suffered during the past month; 65% recovered in one month from the last pain episode, while 35.2% of those reporting disabling low back pain during the past year were aware of recurrent or continual pain. Thus, 7.8% (n = 107) of the whole population could be classified as "low back pain chronics": 86% of the low back pain chronics had trouble with at least one of the daily activities listed, most commonly with sitting at school. Excluding pain in the extremities or sciatica, girls reported various pains more commonly than boys. Moreover, girls reporting recurrent low back pain had more trouble with their daily activities due to pain than boys (p < 0.001), even though the recovery from the last pain episode took the same time in boys and girls. The pupils who had had sciatica at some time, in addition to recurrent low back pain, had more trouble with the 10 daily activities than others with recurrent low back pain (p = 0.014).  相似文献   
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