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861.
Quantitative assessment of immunocytochemical staining for gonadotropin-releasing hormone (GnRH) was undertaken to determine the effects of an intracranial implant of melatonin on the GnRH neuronal system in the male white-footed mouse (Peromyscus leucopus). Melatonin-containing pellets stereotaxically placed in the anterior hypothalamic area (AH) caused a 60% reduction in testes weight relative to control mice with melatonin-free pellets in the AH (p less than 0.01). Subcutaneous melatonin-containing implants had little effect on reproductive state (p less than 0.8). Melatonin pellets in the AH increased significantly both the optical density (OD) for immunostaining of cell bodies in the medial preoptic area and AH (p less than 0.04), and the percentage of area covered by GnRH fibers and beads in the median eminence (p less than 0.01). The melatonin-induced increase in OD of the GnRH cell bodies was independent of the distance of the cells from the melatonin implant, and there was little apparent effect of melatonin on the size and morphology of the GnRH cell bodies, or the trajectories of their fiber pathways. These results support the hypothesis that the antigonadal action of melatonin in the brain involves suppression of the release, rather than the synthesis of GnRH. Also, this effect may not be mediated via a direct action of melatonin on GnRH neurons. The finding that the brain site and time course for melatonin's antigonadal action in male. P. leucopus is similar to that found previously in the female is evidence that melatonin may induce gonadal regression, in part, by helping to suppress the tonic secretion of gonadotropins. 相似文献
862.
L M Cortese D W Greenberger P J Schneider J A Bourret 《American journal of hospital pharmacy》1987,44(11):2514-2518
Perceptions of job characteristics and job satisfaction of central-area technicians and drug-administration technicians at The Ohio State University Hospitals were analyzed. A questionnaire was administered to 79 pharmacy drug-administration technicians; 44 central-area technicians; 10 pharmacy residents, who served as objective raters (5 in the central area and 5 in the decentral area); 13 central-area pharmacists; and 17 decentral-area pharmacists. Perceived job characteristics were measured with the Job Characteristics Inventory; job satisfaction was measured by the Minnesota Job Satisfaction Questionnaire. The two groups of technicians differed significantly in their perceptions of task identity, task significance, and dealing with others. Significantly greater autonomy in technicians' jobs was perceived to exist by pharmacists and raters in both areas than by technicians. Significantly greater task identity was perceived by the central-area technicians than by their raters, and significantly greater task importance was perceived by both groups of technicians than by their pharmacists and raters. Friendship opportunities were perceived to exist to a significantly greater degree by decentral pharmacists and raters than by the drug-administration technicians. In the institution studied, both central-area and drug-administration technicians tended to be dissatisfied with their jobs. Central-area technicians' satisfaction was influenced most by the technicians' relationships with their supervisors and the feelings of accomplishment they gained. Drug-administration technicians were most satisfied if they believed they had opportunities to use their abilities. Efforts to increase job satisfaction among pharmacy technicians should focus on increasing feedback and task identity. 相似文献
863.
J B Ubbink W J Serfontein P J Becker L S de Villiers 《The American journal of clinical nutrition》1987,46(1):78-85
Plasma pyridoxal-5'-phosphate and pyridoxal levels increased significantly (p less than 0.05) when single, oral bolus doses of pyridoxine were increased from 10 to 25 and from 25 to 50 mg in nine female volunteers. However, when the dose was increased to 100 mg, plasma pyridoxal-5'-phosphate levels did not differ significantly from those recorded after the 50 mg dose. Within 3 h plasma pyridoxal levels rose with a factor of 3.85 compared with the 50 mg dose but high pyridoxal levels were eliminated from the circulation. Renal clearance of pyridoxal remained a constant, low percentage (less than 2.0%) of each pyridoxine supplement in spite of the observed very high circulating pyridoxal levels. Pyridoxine supplementation is discussed in relation to circulating pyridoxal-5'-phosphate and pyridoxal availability for cellular metabolism. 相似文献
864.
865.
Curative local excision of rectal adenocarcinoma 总被引:3,自引:0,他引:3
The records of all 28 patients with rectal adenocarcinoma treated by potentially curative local excision by one surgeon (A.M.C.) between 1970 and 1984 were reviewed. Patient age, sex, tumour size, site, degree of differentiation and level of invasion are reported. The procedure was associated with no mortality and minimal morbidity. Twenty-two patients, followed for an average of 51 months, have either died of other causes or remain free of recurrent or disseminated malignancy. Six patients have required further surgery for local recurrence. Of these, one patient has had a repeat local excision while the remaining five patients have had an abdominoperineal excision of the rectum. All six patients, followed since the second operation for an average of 50 months, are free of further recurrent or disseminated disease. The results reported in this review suggest that in a selected group of patients with rectal adenocarcinoma curative local excision may offer a safe alternative to more radical forms of surgery. 相似文献
866.
From 1981 through 1985, the authors studied the changes in monthly nosocomial infection rates at the University of Virginia Hospital in Charlottesville, Virginia using the 95% confidence interval for infection rates as a marker of the efficacy of infection control activities. For a 99-month baseline period, monthly infection rates were calculated and the 95% confidence interval was established. In the 60 study months, each monthly rate was compared with the 95% confidence interval for that particular month. At the end of each study year, the monthly infection rates were incorporated into the existing confidence interval. Of 60 monthly rates during the study period, 30 were below the confidence interval (p less than 0.00001), two were above the confidence interval (p = 0.23), and 28 were within the confidence interval. Since there was no reduction in surveillance activity, patient case-mix index, or laboratory sensitivity for organism recovery, these results suggest that monthly nosocomial infection rates at this hospital have decreased when compared with the baseline period. The use of the 95% confidence interval may provide a measure of the efficacy of infection control activities, suggest temporal intervals requiring more intensive infection surveillance, and provide a method for examining the variability in monthly infection rates. 相似文献
867.
Delta hepatitis virus infection in China 总被引:1,自引:0,他引:1
D Q Wang H H Cheng G Y Minuk L H Liu C M Anand T C Stowe H X Wang D C Ying Y R Tu K A Buchan 《International journal of epidemiology》1987,16(1):79-83
To assess the prevalence, epidemiological features and prognostic implications of hepatitis D (Delta) in Sichuan Province, The People's Republic of China, 649 sera (515 from HBsAg positive patients and 134 from HBsAg negative subjects) were tested by radioimmunoassay (RIA) for antibody to the hepatitis D virus (anti-HD). Forty-seven sera (7.2%) showed some degree of reactivity. Serial dilutions of these sera indicated that prozoning was not responsible for the equivocal results. Thirty-four of the 47 sera were submitted under code to a second laboratory for independent analysis. According to those results anti-HD antibodies were detected in four of these sera. The overall prevalence of anti-HD in the HBsAg positive patients therefore was 0.8% (4/515). On the basis of clinical, biochemical and histological data 427 HBsAg positive sera were further divided into acute Type B hepatitis, chronic Type B hepatitis, healthy carrier state and hepatocellular carcinoma (HCC) subgroups. Two of 65 (3.1%) anti-HD positive sera belonged to the acute Type B hepatitis group; one of 104 (0.9%), the chronic Type B hepatitis group and one of 246 (0.4%), the healthy carrier group. No antibody was detected in sera from 12 HBsAg positive HCC patients. All HBsAg negative patients were negative for anti-HD antibody. The results of this study indicate that despite a high prevalence of hepatitis B virus infection, positive serology for delta virus is uncommon in Sichuan Province, The People's Republic of China. 相似文献
868.
869.
L Beckers 《Acta orthopaedica Belgica》1986,52(6):819-823
870.