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目的:探讨血浆瓦皮素(ET)和心钠素(ANP)在维持性血液透析患者高血压中的作用。方法:尿毒症患者分为维持性血液透析不使用促红细胞生成素(EPO)组、维持性血液透析使用EPO组及尿毒辣症非透析组,以上3组各自分为高血压组和高血压正常组,另设健康对照组。应用放射免疫法检测血浆ET-1和ANP水平。结果:所有尿毒症患者血浆ET-1和ANP水平均高于健康对照组,维持血液透析使用EPO组血浆ET-1和ANP水平高于维持特性血液透不使用EPO组(P<0.05);各组中高血压亚组的血压ET-1水平及ET-1/ANP比值均高于其相应的患者的高血压同 浆ET-1水平井高升以及ET-1和ANP比值的增大有密切关系。 相似文献
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Jennifer S. Polus Riley A. Bloomfield Edward M. Vasarhelyi Brent A. Lanting Matthew G. Teeter 《The Journal of arthroplasty》2021,36(2):573-578
BackgroundThe prevalence of falls affects the wellbeing of aging adults and places an economic burden on the healthcare system. Integration of wearable sensors into existing fall risk assessment tools enables objective data collection that describes the functional ability of patients. In this study, supervised machine learning was applied to sensor-derived metrics to predict the fall risk of patients following total hip arthroplasty.MethodsAt preoperative, 2-week, and 6-week postoperative appointments, patients (n = 72) were instrumented with sensors while they performed the timed-up-and-go walking test. Preoperative and 2-week postoperative data were used to form the feature sets and 6-week total times were used as labels. Support vector machine and linear discriminant analysis classifier models were developed and tested on various combinations of feature sets and feature reduction schemes. Using a 10-fold leave-some-subjects-out testing scheme, the accuracy, sensitivity, specificity, and area under the receiver-operator curve (AUC) were evaluated for all models.ResultsA high performance model (accuracy = 0.87, sensitivity = 0.97, specificity = 0.46, AUC = 0.82) was obtained with a support vector machine classifier using sensor-derived metrics from only the preoperative appointment. An overall improved performance (accuracy = 0.90, sensitivity = 0.93, specificity = 0.59, AUC = 0.88) was achieved with a linear discriminant analysis classifier when 2-week postoperative data were added to the preoperative data.ConclusionThe high accuracy of the fall risk prediction models is valuable for patients, clinicians, and the healthcare system. High-risk patients can implement preventative measures and low-risk patients can be directed to enhanced recovery care programs. 相似文献
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Nicola De Stefano Victor Navarro-Tableros Dorotea Roggio Alberto Calleri Federica Rigo Ezio David Alessandro Gambella Daniela Bassino Antonio Amoroso Damiano Patrono Giovanni Camussi Renato Romagnoli 《Transplant international》2021,34(9):1607-1617
Livers from donors after circulatory death (DCD) are a promising option to increase the donor pool, but their use is associated with higher complication rate and inferior graft survival. Normothermic machine perfusion (NMP) keeps the graft at 37°C, providing nutrients and oxygen supply. Human liver stem cell-derived extracellular vesicles (HLSC-EVs) are able to reduce liver injury and promote regeneration. We investigated the efficacy of a reconditioning strategy with HLSC-EVs in an experimental model of NMP. Following total hepatectomy, rat livers were divided into 4 groups: (i) healthy livers, (ii) warm ischemic livers (60 min of warm ischemia), (iii) warm ischemic livers treated with 5 × 108 HLSC-EVs/g-liver, and (iv) warm ischemic livers treated with a 25 × 108 HLSC-EVs/g-liver. NMP lasted 6 h and HLSC-EVs (Unicyte AG, Germany) were administered within the first 15 min. Compared to controls, HLSC-EV treatment significantly reduced transaminases release. Moreover, HLSC-EVs enhanced liver metabolism by promoting phosphate utilization and pH self-regulation. As compared to controls, the higher dose of HLSC-EV was associated with significantly higher bile production and lower intrahepatic resistance. Histologically, this group showed reduced necrosis and enhanced proliferation. In conclusion, HLSC-EV treatment during NMP was feasible and effective in reducing injury in a DCD model with prolonged warm ischemia. 相似文献
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Sonoo Mizuiri Yoshiko Nishizawa Toshiki Doi Kazuomi Yamashita Kenichiro Shigemoto Koji Usui Michiko Arita Takayuki Naito Shigehiro Doi Takao Masaki 《Renal failure》2021,43(1):371
ObjectiveA high coronary artery calcification score (CACS) may be associated with high mortality in patients undergoing hemodialysis (HD). Recently, effects of iron on vascular smooth muscle cell calcification have been described. We aimed to investigate the relationships between iron, CACS, and mortality in HD patients.MethodsWe studied 173 consecutive patients who were undergoing maintenance HD. Laboratory data and Agatston’s CACS were obtained at baseline for two groups of patients: those with CACS ≥400 (n = 109) and those with CACS <400 (n = 64). Logistic regression analyses for CACS ≥400 and Cox proportional hazard analyses for mortality were conducted.ResultsThe median (interquartile range) age and duration of dialysis of the participants were 67 (60–75) years and 73 (37–138) months, respectively. Serum iron (Fe) and transferrin saturation (TSAT) levels were significantly lower in participants with CACS ≥400 than in those with CACS <400, although the serum ferritin concentration did not differ between the groups. TSAT ≥21% was significantly associated with CACS ≥400 (odds ratio 0.46, p<0.05). TSAT ≥17%, Fe ≥63 µg/dL, and ferritin ≥200 ng/mL appear to protect against 5-year all-cause mortality in HD patients, independent of conventional risk factors of all-cause mortality (p < 0.05).ConclusionWe have identified associations between iron, CACS, and mortality in HD patients. Lower TSAT was found to be an independent predictor of CACS ≥400, and iron deficiency (low TSAT, iron, or ferritin) was a significant predictor of 5-year all-cause mortality in HD patients. 相似文献
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Gabriel Stefan Ana Maria Mehedinti Iuliana Andreiana Adrian Dorin Zugravu Simona Cinca Ruxandra Busuioc Ioana Miler Simona Stancu Ligia Petrescu Ioana Dimitriu Elena Moldovanu Diana Elena Crasnaru Georgeta Gugonea Valentin Georgescu Victor Dan Strambu Cristina Capusa 《Renal failure》2021,43(1):49
Background There is limited information about the clinical characteristics, treatment and outcome of maintenance hemodialysis patients with COVID-19. Moreover, regional differences are also conceivable since the extend and severity of outbreaks varied among countries.Methods In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of 37 maintenance hemodialysis patients (median age 64 years, 51% men) hospitalized with COVID-19 from 24 March to 22 May 2020 as confirmed by real-time PCR.Results The most common symptoms at admission were fatigue (51%), fever (43%), dyspnea (38%) and cough (35%). There were 59% mild/moderate patients and 41% severe/critical patients. Patients in the severe/critical group had a significantly higher atherosclerotic burden since diabetic kidney disease and vascular nephropathies were the most common primary kidney diseases and eighty percent of them had coronary heart disease. Also, Charlson comorbidity score was higher in this group. At admission chest X-ray, 46% had ground-glass abnormalities. Overall, 60% patients received hydroxychloroquine, 22% lopinavir–ritonavir, 11% tocilizumab, 24% systemic glucocorticoids, and 54% received prophylactic anticoagulation. Seven (19%) patients died during hospitalization and 30 were discharged. The main causes of death were cardiovascular (5 patients) and respiratory distress syndrome (2 patients). In Cox regression analysis, lower oxygen saturation, anemia and hypoalbuminemia at admission were associated with increased mortality.Conclusions In conclusion, we observed a high mortality rate among maintenance hemodialysis patients hospitalized for COVID-19. Anemia, lower serum albumin and lower basal oxygen saturation at admission were factors associated with poor prognosis. 相似文献
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PurposeThis study aimed to investigate the association between clinical factors and temporary changes in functional performance in patients undergoing hemodialysis.MethodsThis was a retrospective, longitudinal observational study conducted from 2015 to 2017. Eight-two patients undergoing hemodialysis in the outpatient clinic were enrolled. Functional performance was measured using the Karnofsky Performance Status (KPS) scale. Collected data for analysis included demographics, laboratory parameters, and KPS scale scores. All participants were grouped into a high KPS cluster and a low KPS cluster based on dynamic changes in KPS scales from 2015 to 2017.ResultsParticipants in the high KPS cluster demonstrated an approximate trend, and those in the low KPS cluster demonstrated a low pattern. By stepwise selection model analysis, age (OR 1.12, 95% CI 1.03–1.23, p = 0.011), serum BUN (OR 1.08, 95% CI 1.02–1.16, p = 0.015), calcium levels (OR 3.24, 95% CI 1.2–8.73, p = 0.02), and beta-2-microglobulin (OR > 1.0, CI >1.00-<1.01, p = 0.031) showed risk for the low KPS cluster. Male sex (OR 0.20, 95% CI 0.04–0.96, p = 0.045) and albumin level (OR 0.02, 95% CI 0–0.4, p = 0.009) showed a low risk for the low KPS cluster.ConclusionsA different trajectory pattern was observed between the high and low KPS clusters in a 3-year period. Risk factors for the low KPS cluster were age, serum BUN, calcium, and beta-2-microglobulin levels. Male sex and serum albumin levels reduced the risk for the low KPS cluster. 相似文献