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811.
Circadian rhythms play a very important role on metabolic process and have considerable effects on growth, especially in ectotherms. Like variation in hormone levels, the sensitivity of target cells may show diurnal or seasonal fluctuations. The aim of this study was to compare the effects of morning versus evening injections of growth hormone and prolactin on malic enzyme, glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase, aspartate aminotransferase, alanine aminotransferase and Na+,K+-ATPase in a teleost Anabas testudineus. Activities of malic enzyme, glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase of the two control groups themselves differ significantly at morning and evening. Early morning administration of growth hormone increases malic enzyme, glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase activities while evening administration of growth hormone does not effect these enzymes. Transaminase activities were stimulated by morning and evening administration of GH and PRL. Na+,K+-ATPase activity was stimulated by morning administration and inhibited by evening treatment of both hormones. The results reveal that a given hormone may provide a different message to the target tissues at different periods of the day. 相似文献
812.
Leena Taji Doneal Thomas Matthew J. Oliver Jane Ip Yiwen Tang Angie Yeung Rebecca Cooper Andrew A. House Phil McFarlane Peter G. Blake 《CMAJ》2021,193(8):E278
BACKGROUND:Patients undergoing long-term dialysis may be at higher risk of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and of associated disease and mortality. We aimed to describe the incidence, risk factors and outcomes for infection in these patients in Ontario, Canada.METHODS:We used linked data sets to compare disease characteristics and mortality between patients receiving long-term dialysis in Ontario who were diagnosed SARS-CoV-2 positive and those who did not acquire SARS-CoV-2 infection, between Mar. 12 and Aug. 20, 2020. We collected data on SARS-CoV-2 infection prospectively. We evaluated risk factors for infection and death using multivariable logistic regression analyses.RESULTS:During the study period, 187 (1.5%) of 12 501 patients undergoing dialysis were diagnosed with SARS-CoV-2 infection. Of those with SARS-CoV-2 infection, 117 (62.6%) were admitted to hospital and the case fatality rate was 28.3%. Significant predictors of infection included in-centre hemodialysis versus home dialysis (odds ratio [OR] 2.54, 95% confidence interval [CI] 1.59–4.05), living in a long-term care residence (OR 7.67, 95% CI 5.30–11.11), living in the Greater Toronto Area (OR 3.27, 95% CI 2.21–4.80), Black ethnicity (OR 3.05, 95% CI 1.95–4.77), Indian subcontinent ethnicity (OR 1.70, 95% CI 1.02–2.81), other non-White ethnicities (OR 2.03, 95% CI 1.38–2.97) and lower income quintiles (OR 1.82, 95% CI 1.15–2.89).INTERPRETATION:Patients undergoing long-term dialysis are at increased risk of SARS-CoV-2 infection and death from coronavirus disease 2019. Special attention should be paid to addressing risk factors for infection, and these patients should be prioritized for vaccination.As of Aug. 20, 2020, in Ontario, Canada’s most populous province, almost 41 000 people had tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19),1 which represented 0.3% of the provincial population. Close to 2800 people had died, a case fatality rate of 6.8%.2Patients undergoing dialysis have high rates of comorbid conditions, are often older adults, have varying degrees of immunosuppression and are more likely to reside in long-term care, which puts them at risk of both acquiring SARS-CoV-2 and developing complicated disease.3,4 Furthermore, in Ontario, those who receive in-centre hemodialysis typically have 3 treatments per week in outpatient units located in or affiliated with hospitals, and the consequent inability to fully self-isolate means that patients undergoing hemodialysis likely have an even higher risk of SARS-CoV-2 infection.3,4 Recent studies support this but do not compare infection rates with those in the local population of patients not undergoing dialysis.5–10 Several studies have reported SARS-CoV-2 infection in single or multicentre cohorts of patients undergoing dialysis,5–10 but we are unaware of any that have identified risk factors for infection at the level of a large region. Some studies have found that patients with SARS-CoV-2 infection who are undergoing dialysis are at high risk of severe illness and death.6–10 相似文献
813.
We monitored the behaviour of farmed silver foxes housed in family units in enlarged cage systems from weaning until late
October. Activity of family members, use of space available, and aggressive acts were recorded. Aggressiveness between family
members increased from July until October, leading to a more scattered use of the available space. Furthermore, the mean activity
level of family members increased, and the synchrony of activity decreased. We conclude that social tension in the fox families
increased gradually during the autumn, leading to dispersion of the family members.
Received in revised form: 22 October 2001
Electronic Publication 相似文献