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51.
To ascertain the frequency and risk factors for post-lumbar puncture headache, we studied all adults who had an ambulatory lumbar puncture (LP) in a 1-year period. Patients filled out a questionnaire detailing their headache experience on the day of, and the 6 days following, LP. Those who did not return the questionnaire were telephoned. We systematically collected and analyzed many items, including the lumbar puncturist's experience, the degree of difficulty of the LP, CSF findings, final diagnosis, and the patient's demographic characteristics. Patients reporting headache before LP were more likely to report post-LP headaches. In addition to this, younger female patients with a lower body mass index have the highest risk of developing post-LP headaches. CSF opening pressure, cells, and protein, patient's position during LP, the duration of recumbency following LP, and the amount of CSF removed at the time of LP did not influence the occurrence of headache.  相似文献   
52.
Seasonal variation in physical activity, back extensor muscle strength (BES), and bone mineral density (BMD) of the lumbar spine was studied in 65 healthy postmenopausal women. Physical activity score (PAS) was assessed with an ordinal scale (0-18); this score and the BES were obtained monthly for 2 years (25 readings). BMD values were obtained semiannually (5 readings). A periodic (cosine) regression model was fit to each subject's PAS and BES data to obtain individual estimates of the annual peak day d and the average annual range due to seasonality. There was a strong (P less than 0.001) seasonal pattern in physical activity; August 3 was the average peak day, and the seasonal range was 2.0 PAS units. There was modest (P = 0.047) seasonality in BES; June 6 was the estimated peak day, and the seasonal range was 8.22 pounds (about 7% of the 0.002), and the highest monthly average BMD was in August. This seasonal range of 1.4% is larger than the average annual decline with age in BMD observed in longitudinal studies of postmenopausal women. The results of this study have important implications for the planning of longitudinal studies involving changes in physical activity or bone mass in geographic areas with diverse seasons.  相似文献   
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Persons greater than or equal to 90 years of age represent a rapidly growing subset of the population, but little data exist on their utilization of the health care system. Population-based data capabilities of the Rochester/Olmsted County Epidemiology Project were used to study the performance of surgery among persons greater than or equal to 90 years of age for the 11-year period, 1975-1985. During this time, 224 residents of Olmsted County, Minnesota underwent 301 separate operations. The annual operation rate increased over the course of the study (trend test, p less than 0.001), reaching a plateau of 89.0 per 1000 person-years. This suggests a potential for nearly 91,000 operations annually in this age group based on 1987 U.S. Census estimates. Ninety-two per cent were discharged from the hospital alive, and 5-year survival was consistent with that expected (23% vs. 17%). Increased longevity of the general population, combined with increased performance of surgery in this rapidly growing segment of the population, may have significant implications for health care planning.  相似文献   
55.
The effect of aprotinin on the absorption of regular insulin was assessed in normal man. Ten units of Actrapid insulin were subcutaneously injected together with 1.4 mg aprotinin (i.e., 0.5 ml of Trasylol) or an equivalent volume of physiologic saline (controls) into the thighs of overnight-fasted normal subjects. Aprotinin caused an increase in the rate of insulin entry into the circulation; the absolute amount of insulin that was detected in the circulation during the course of the experiment was also higher. In addition, the onset of the hypoglycemic action of exogenous insulin was significantly accelerated when insulin was administered together with aprotinin. These data suggest that aprotinin increases the absorption rate of subcutaneously injected insulin from its depot into the circulation, possibly by an inhibition of the local degradation of exogenous insulin at the injection site.  相似文献   
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Patterns of bone loss in the axial and the appendicular skeleton were studied in 185 normal volunteers (105 women and 82 men; age range, 20--89 yr) and in 76 women and 9 men with vertebral fractures due to osteoporosis. Bone mineral density was measured in vivo at the lumbar spine (predominantly trabecular bone) by dual photon absorptiometry and at the midradius (greater than 95% cortical bone) and distal radius (75% cortical and 25% trabecular bone) by single photon absorptiometry. In normal women, bone diminution from the vertebrae began in young adulthood and was linear. In the appendicular skeleton, bone diminution did not occur until age 50 yr, was accelerated from aged 51 to 65 yr, and then decelerated somewhat after age 65 yr. Overall bone diminution throughout life was 47% for the vertebrae, 30% for the midradius, and 39% for the distal radius. In normal men, vertebral and appendicular bone diminution with aging was minimal or insignificant. Mean bone mineral density was lower in patients with osteoporosis than in age- and sex-matched normal subjects at all three scanning sites, although spinal measurements discriminated best; however, there was considerable overlap. By age 65 yr, half of the normal women (and by age 85 yr, virtually all of them) had vertebral bone mineral density values below the 90th percentile of women with vertebral fractures and, thus, might be considered to have asymptomatic osteoporosis. For men, the degree of overlap was less. The data suggest that disproportionate loss of trabecular bone from the axial skeleton is a distinguishing characteristic of spinal osteoporosis.  相似文献   
59.
This report presents data from the Ontario Child Health Study on the prevalence of individual emotional symptoms, the variation of prevalence rates of emotional disorders as a function of demographic factors, and the rates of service utilization for children with these disorders. To survey Ontario children from 4 to 16 years of age, a stratified random sample of 3,294 children was drawn from all household dwellings listed in the 1981 Census. The prevalence rates for emotional disorders in male and female children aged 4 to 11 years were 10.1% and 10.7%, respectively. For adolescents aged 12 to 16 years, the prevalence rate rose to 13.7% for females and fell to 5.0% for males. Children with emotional disorders were frequently found to meet criteria for more than one disorder. Only one in five children with emotional disorders had received mental health or social services in the 6 months prior to the survey.  相似文献   
60.
We have demonstrated that, in determining the number of cytons (cell bodies) in a ganglion, it is important to consider the range of sizes of cytons and their associated nucleoli in correcting for the split-cell counting error. We have established the mathematical relationship between nucleolus diameter and cytons diameter microscopically in serial sections. An improved method, utilizing semi-automatic techniques and programmed calculation and plotting, is presented for estimating the volume of the ganglion, the number of cytons of neurons per ganglion, and the corrected frequency distribution of diameters of cytons of neurons.  相似文献   
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