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51.
In vitro exposure of DE‐71, a penta‐PBDE mixture,on immune endpoints in bottlenose dolphins (Tursiops truncatus) and B6C3F1 mice 下载免费PDF全文
Jena R. Wirth Margie M. Peden‐Adams Natasha D. White Gregory D. Bossart Patricia A. Fair 《Journal of applied toxicology : JAT》2015,35(2):191-198
Polybrominated diphenyl ethers (PBDEs) are an emerging contaminant of concern with low level exposures demonstrating toxicity in laboratory animals and wildlife, although immunotoxicity studies have been limited. Bottlenose dolphin peripheral blood leukocytes (PBLs) and mouse splenocytes were exposed to environmentally relevant DE‐71 (a penta‐PBDE mixture) concentrations (0–50 µg ml?1) in vitro. Natural killer (NK) cell activity and lymphocyte (B and T cell) proliferation were evaluated using the parallelogram approach for risk assessment. This study aimed to substantiate results from field studies with dolphins, assess the sensitivities between the mouse model and dolphins, and to evaluate risk using the parallelogram approach. In mouse cells, NK cell activity increased at in vitro doses 0.05, 0.5 and 25 µg DE‐71 ml?1, whereas proliferation was not modulated. In dolphin cells, NK cell activity and lymphocyte proliferation was not altered after in vitro exposure. In vitro exposure of dolphin PBLs to DE‐71 showed similar results to correlative field studies; NK cell activity in mice was more sensitive to in vitro exposure than dolphins, and the parallelogram approach showed correlation with all three endpoints to predict risk in bottlenose dolphins. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
52.
Steven Hawken Jeffrey C. Kwong Shelley L. Deeks Natasha S. Crowcroft Allison J. McGeer Robin Ducharme Michael A. Campitelli Doug Coyle Kumanan Wilson 《Emerging infectious diseases》2015,21(2):224-231
It is unclear whether seasonal influenza vaccination results in a net increase or decrease in the risk for Guillain-Barré syndrome (GBS). To assess the effect of seasonal influenza vaccination on the absolute risk of acquiring GBS, we used simulation models and published estimates of age- and sex-specific risks for GBS, influenza incidence, and vaccine effectiveness. For a hypothetical 45-year-old woman and 75-year-old man, excess GBS risk for influenza vaccination versus no vaccination was −0.36/1 million vaccinations (95% credible interval −1.22 to 0.28) and −0.42/1 million vaccinations (95% credible interval, –3.68 to 2.44), respectively. These numbers represent a small absolute reduction in GBS risk with vaccination. Under typical conditions (e.g. influenza incidence rates >5% and vaccine effectiveness >60%), vaccination reduced GBS risk. These findings should strengthen confidence in the safety of influenza vaccine and allow health professionals to better put GBS risk in context when discussing influenza vaccination with patients. 相似文献
53.
Natasha Aleksova Ana C. Alba Chun-Po S. Fan Faizan Amin Omid Kiamanesh Caroline McGuinty Hanna Lee Juan G. Duero Posada Heather J. Ross Filio Billia Vivek Rao 《The Canadian journal of cardiology》2021,37(3):467-475
BackgroundAs patients with advanced heart failure are living longer, defining the impact of left ventricular assist devices (LVADs) on outcomes in an aging population is of great importance. We describe overall survival, rates of adverse events (AEs), and post-AE survival in patients age ≥ 70 years vs age 50-69 years after destination-therapy (DT) LVAD implantation.MethodsA retrospective analysis was conducted with the use of the International Society for Heart and Lung Transplantation Mechanically Assisted Circulatory Support (IMACS) registry. All adults age ≥ 50 years with a continuous-flow DT LVAD from 2013 to 2017 were included. The primary outcome was all-cause mortality. The secondary outcomes were the incidence of and survival after gastrointestinal (GI) bleeding, infection, stroke, pump thrombosis, pump exchange, and right-side heart failure. Mortality and AEs were assessed with the use of competing risk models.ResultsAt total of 5,572 patients were included: 3,700 aged 50-69 and 1,872 aged ≥ 70. All-cause mortality by 42 months was 55.8% in patients aged ≥ 70 and 44.8% in patients aged 50-69 (P = 0.001). Patients aged ≥ 70 had a 37.8% higher risk of death after DT LVAD implantation (hazard ratio 1.378, 95% CI 1.251-1.517). Patients aged ≥ 70 had higher risk of GI bleeding but lower risk of right-side heart failure. There was no difference between age groups for risk of infection or stroke. Experiencing any AE was associated with an increased risk of death that did not vary with age.ConclusionsPatients aged ≥ 70 years have reduced survival after DT LVAD, in part because of increased GI bleeding, while the incidence of other AEs is similar to that of patients aged 50-69 years. Careful patient selection beyond age alone may allow for optimal outcomes after DT LVAD implantation. 相似文献
54.
Samad Noreen Manzoor Natasha Muneer Zahra Bhatti Sheraz A. Imran Imran 《Metabolic brain disease》2021,36(8):2535-2552
Metabolic Brain Disease - Thymoquinone (Tq), an active compound of Nigella sativa, has been known for its anti-inflammatory, antioxidant, and neuroprotective characteristics. The present study is... 相似文献
55.
Xu Yanzhu Khamis Noren Khosravi-Hafshejani Touraj Tan Julia Miles Ellen Avina-Zubieta J. Antonio Shojania Kam Nimmo Michael Dehghan Natasha 《Clinical rheumatology》2021,40(12):4983-4991
Clinical Rheumatology - Antineutrophil cytoplasmic antibodies (ANCA) serology can aid in the diagnosis and classification of ANCA-associated vasculitides (AAV). However, it is often ordered in... 相似文献
56.
Diastolic blood pressure is the first to rise in association with early subclinical obstructive sleep apnea: lessons from periodic examination screening 总被引:12,自引:0,他引:12
BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated with long-term cardiovascular morbidity. Little is known about these relations at early stages. We conducted a case-control study in which we analyzed the clinical characteristics of young adults who underwent a periodic health examination and were screened for, and eventually found to experience, OSAS. METHODS: We identified 121 subjects newly diagnosed in a sleep study as having OSAS, and 229 matched control subjects in which screening for OSAS was negative. All had a medical interview, physical examination, and routine laboratory tests. RESULTS: Subjects who had OSAS had a higher, body mass index (3-kg/m(2) difference) and a higher diastolic blood pressure (4-mm Hg difference) value, without elevation in systolic blood pressure. There was no metabolic difference (lipids profile and fasting glucose levels) between groups. CONCLUSIONS: Diastolic blood pressure is higher early in the course of OSAS. Long term follow-up may determine effects of prevention and early intervention in OSAS and associated hypertension. 相似文献
57.
A randomized controlled trial of cognitive behavior therapy, relaxation training, and routine clinical care for the irritable bowel syndrome 总被引:5,自引:0,他引:5
Boyce PM Talley NJ Balaam B Koloski NA Truman G 《The American journal of gastroenterology》2003,98(10):2209-2218
OBJECTIVES: Psychological treatments are considered to be useful in the irritable bowel syndrome (IBS), although the evidence is based on small, often flawed trials. Although cognitive behavior therapy (CBT) and relaxation therapy have both been promising, we hypothesized that CBT would be superior to relaxation and standard care alone in IBS patients. The objective of this study was to test this assumption by comparing the effects of cognitive behavior therapy with relaxation therapy and routine clinical care alone in individuals with IBS. METHODS: Patients (n = 105) with Rome I criteria for IBS were recruited from advertisement (n = 51) and outpatient clinics (n = 54); those patients with resistant IBS were not included. A randomized controlled trial with three arms (standard care for all groups plus either CBT or relaxation) for 8 wk was conducted, which applied blinded outcome assessments using validated measures with 1 yr of follow-up. The primary outcome for this study was bowel symptom severity. RESULTS: Of 105 patients at the commencement of treatment, the mean bowel symptom frequency score for the whole sample was 21.1 and at the end of treatment had fallen to 18.1; this persisted at the 52-wk follow-up, with a significant linear trend for scores to change over time (F = 39.57 p < 0.001). However, there were no significant differences among the three treatment conditions. Significant changes over time were found for physical functioning (F = 4.37, p < 0.001), pain (F = 3.12, p < 0.05), general health (F = 2.71, p < 0.05), vitality (F = 2.94, p < 0.05), and the social functioning scales on the Medical Outcomes Study Short Form 36 (F = 4.08, p < 0.05); however, all three arms showed similar improvement. There were significant reductions in anxiety, depression, and locus of control scales, but no significant differences among the treatment groups were detected. CONCLUSION: Cognitive behavior and relaxation therapy seem not to be superior to standard care alone in IBS. 相似文献
58.
Cesaro S Locatelli F Lanino E Porta F Di Maio L Messina C Prete A Ripaldi M Maximova N Giorgiani G Rondelli R Aricò M Fagioli F 《Haematologica》2008,93(11):1694-1701
59.
Severe hypoleptinaemia associated with insulin resistance in patients with common variable immunodeficiency 总被引:1,自引:0,他引:1
Ferraroni NR Geloneze B Mansour E Perroud AP Muscelli EO Tambascia M de Lima Zollner R Velloso LA 《Clinical endocrinology》2005,63(1):63-65
Objective Common variable immunodeficiency (CVI) is a primary immunodeficiency syndrome characterized by impaired production of antibodies and recurrent infections. Delay in diagnosis leads to metabolic wastage and low body weight. Leptin, a hormone produced by white adipose tissue, modulates insulin action by signal transduction cross‐talk and by direct action on pancreatic beta‐cells. We hypothesized that patients with CVI might present a defective regulation of leptin production and insulin resistance. Patients Thirteen CVI patients (39 ± 11 years) under gammaglobulin replacement were evaluated in parallel with 13 gender‐, age‐, body weight‐ and body mass index (BMI)‐matched healthy voluntaries, and with data from two large population series, the Bruneck and the Hoorn Studies. Measurements Serum leptin and insulin levels, homeostasis model assessment – insulin resistance (HOMA‐IR), body composition, haematological, biochemical and immunoglobulin measurements were obtained. Data were analysed by a one‐way analysis of variance (anova ) and by Pearson's rank analysis. The institutional ethics committee approved the study, and informed consent was obtained from patients and controls. Results No differences were found between CVI and the control group when comparing gender distribution, age, body weight, BMI, waist/hip ratio, relative body fat and fasting glucose levels. Leptin levels were lower (P < 0·05) in CVI patients than in controls and lower than fasting leptin levels detected in a large population study. CVI patients’ serum leptin levels did not correlate with BMI (r = 0·074, P = 0·8) and their high HOMA‐IR indicated insulin resistance. Conclusions CVI patients are relatively hypoleptinaemic and insulin resistant, and their serum leptin levels are not correlated to their BMI. 相似文献
60.