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931.
932.
Timothy G. Laske Henry J. Harlow David L. Garshelis Paul A. Iaizzo 《Journal of cardiovascular translational research》2010,3(5):559-569
American black bears survive winter months without food and water while in a mildly hypothermic, hypometabolic, and inactive state, yet they appear to be able to return to near-normal systemic function within minutes of arousal. This study’s goal was to characterize the cardiovascular performance of overwintering black bears and elicit the underlying mechanisms enabling survival. Mid-winter cardiac electrophysiology was assessed in four wild black bears using implanted data recorders. Paired data from early and late winter were collected from 37 wild bears, which were anesthetized and temporarily removed from their dens to record cardiac electrophysiological parameters (12-lead electrocardiograms) and cardiac dimensional changes (echocardiography). Left ventricular thickness, primary cardiac electrophysiological parameters, and cardiovascular response to threats (“fight or flight” response) were preserved throughout winter. Dramatic respiratory sinus arrhythmias were recorded (cardiac cycle length variations up to 865%) with long sinus pauses between breaths (up to 13 s). The accelerated heart rate during breathing efficiently transports oxygen, with the heart “resting” between breaths to minimize energy usage. This adaptive cardiac physiology may have broad implications for human medicine. 相似文献
933.
Samue Nwadioha Julie O Egesie Henry Emejuo Elizabeth Iheanacho 《Asian Pacific journal of tropical medicine》2010,3(6):483-485
ObjectiveTo investigate the prevalence of pathogens of abnormal vaginal discharges and to improve the current syndromic management of abnormal vaginal discharge.MethodsA prospective study of pathogens of abnormal vaginal discharge was carried out from December 2007 to December 2008. Samples of female genital swabs were collected from Obstetrics and Gynecology Units of Aminu Kano Teaching Hospital, Kano, Nigeria, and analyzed by microscopy, culture and sensitivity test in Medical Microbiology Laboratory of Aminu Kano Teaching Hospital.ResultsMicroorganisms were detected in 70% (1 400) of a total 2 000 female genital swabs studied. Candida species peaked with 42.0% (840), followed by Gardnerella vaginalis, a pathogen of bacteria vaginosis with 26.0%. The distribution of abnormal vaginal discharge was highest in young adults aged from 21 to 30 years.ConclusionsThe commonest Microorganisms of infective vaginal discharge were Candida species, followed by Gardnerella vaginalis, a pathogen of bacterial vaginosis. Vaginal discharge was prevalent among young adults. We recommend prevention, early diagnosis and prompt treatment of infected female, especially among the young, sexually active group in order to reduce the menace of HIV transmission. 相似文献
934.
935.
936.
Intramedullary neurenteric cysts (NEC) without associated malformations are extremely rare and, to our knowledge, have never been reported in association with calcification. We report a unique imaging presentation as a partially calcified mass of an isolated intramedullary neuroenteric cyst of the lower thoracic spinal cord with pathologic correlation. The literature for isolated forms of intramedullary NEC since the advent of magnetic resonance imaging is also reviewed. 相似文献
937.
Effectiveness of heptavalent pneumococcal conjugate vaccine in children younger than five years of age for prevention of pneumonia 总被引:13,自引:0,他引:13
Black SB Shinefield HR Ling S Hansen J Fireman B Spring D Noyes J Lewis E Ray P Lee J Hackell J 《The Pediatric infectious disease journal》2002,21(9):810-815
OBJECTIVE: To determine the effectiveness of the Wyeth heptavalent pneumococcal conjugate vaccine against clinical and radiograph-confirmed pneumonia in children. METHODS: The heptavalent CRM(197) pneumococcal conjugate vaccine (PCV) was given to infants at 2, 4, 6 and 12 to 15 months of age in a randomized, double blind trial. Children were randomized to receive either the CRM(197) PCV (vaccine group) or the meningococcal type C CRM(197) conjugate vaccine (control group). The primary outcome of this trial was invasive pneumococcal disease. In addition children with the clinical diagnosis of pneumonia in the study population were identified through review of automated inpatient, emergency and outpatient databases. The subset of the cohort of these children who had chest radiographs obtained at the time of diagnosis was identified, and the original reading of their radiographs by the radiologist was obtained from automated databases. Rates of clinically diagnosed pneumonia, of pneumonia with a radiograph obtained regardless of result, of pneumonia with positive radiograph (consolidation, empyema or parenchymal infiltrate) and of pneumonia with only perihilar infiltrates were compared between vaccinated and nonvaccinated groups. In addition risk of disease pneumonia was evaluated by race and ethnicity. RESULTS: The incidence of a first pneumonia episode in the control group was 55.9 per 1000 person-years. A radiograph was obtained in 61% of episodes, a positive radiograph in 21% and perihilar findings in an additional 5%. In per protocol follow-up of children given PCV, first episodes of all clinically diagnosed pneumonia were reduced by 4.3% [95% confidence interval (CI), -3.5, 11.5%, = 0.27], episodes with a radiograph were reduced by 9.8% (CI 0.1, 18.5%, < 0.05) and episodes with a positive radiograph were reduced by 20.5% (CI 4.4, 34.0, = 0.02). In the intent to treat analysis including all episodes after randomization, episodes with a positive radiograph were reduced by 17.7%, =.01). The greatest impact was in the first year of life with a 32.2% reduction and a 23.4% reduction in the first 2 years, but only a 9.1% reduction in children >2 years of age. Asians, blacks and Hispanics were at higher risk of pneumonia than were whites, but there was no evidence of ethnic variation in PCV effectiveness. Ten of the 11 cases of pneumococcal pneumonia with a positive blood culture were in the control group. CONCLUSION: The pneumococcal conjugate vaccine tested was effective in reducing the risk of pneumonia in young children. 相似文献
938.
The fetal liver is the primary site of fetal serine production. The regulation of this unique fetal hepatic serine production is unknown. We hypothesized that serine production would be responsive to folate cofactor supply or hormonal regulation. To test this hypothesis, we determined the effect of key folate cofactors and insulin and glucagon on serine and glycine metabolism in primary culture of fetal ovine hepatocytes. Hepatocytes were cultured in serum-free, low-folate media [5 nM 5-methyl-tetrahydrofolate (THF)] with or without 50 nM 5,10-methylene-THF (MTHF) or 5-formyl-THF (FTHF). Serine and glycine production (P) and utilization (U) were determined by stable isotope dilution with [1-(13)C]serine and [1-(13)C]glycine for 24 h. The effect of insulin (1 microM) or glucagon (1 micro M) was determined in a similar manner. Under basal conditions, serine P (43.2 +/- 5.1 micromol/mg DNA per 24 h) is greater than serine U (24.1 +/- 3.1 micromol/mg DNA per 24 h), whereas glycine U (27.3 +/- 3.0 micromol/mg DNA per 24 h) exceeds glycine P (16.7 +/- 1.9 micromol/mg DNA per 24 h). MTHF results in a significant decrease in serine U (16.0 +/- 2.7 micromol/mg DNA per 24 h; p = 0.02 versus low folate), with no change in serine P. FTHF reduces serine P (36.2 +/- 4.9 micromol/mg DNA per 24 h; p = 0.01), but does not alter serine U. There were no effects on glycine metabolism with 50 nM MTHF or FTHF. Serine P and U were inversely correlated whereas glycine P and U were directly correlated with the media concentration of MTHF or FTHF. Glucagon treatment increased serine U by 260 +/- 65% versus low folate (p = 0.0004) but did not change serine P. Insulin treatment led to parallel increases in both serine P and U. Both folate cofactor availability and hormone concentrations regulate serine metabolism in the fetal liver. We speculate that serine metabolism may be a marker of fetal hepatic folate cofactor supply. 相似文献
939.
Santhini Jeyarajah Andre Chow Paul Ziprin Henry Tilney Sanjay Purkayastha 《International journal of colorectal disease》2010,25(9):1037-1046
Purpose
Proctalgia fugax (PF) is a benign anorectal condition which has been described in the literature since the nineteenth century commonly presenting to general surgeons. There is little high level evidence on the subject and its therapeutic modalities. We aimed through this systematic literature review to outline the definition and diagnostic criteria of this condition, the aetiology and differential diagnoses and describe the different treatment modalities that have been attempted and their success. 相似文献940.
Kathryn M. Dalbec C. Max Schmidt Terence E. Wade Sue Wang Deborah A. Swartz-Basile Henry A. Pitt Nicholas J. Zyromski 《Digestive diseases and sciences》2010,55(7):2108-2112