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81.
ObjectiveThe exposure to artificial light at night (ALAN) disrupts the biological rhythms and has been associated with the development of metabolic syndrome. MicroRNAs (miRNAs) display a critical role in fine-tuning the circadian system and energy metabolism. In this study, we aimed to assess whether altered miRNAs expression in the liver underlies metabolic disorders caused by disrupted biological rhythms.ResultsWe found that C3H/HePas mice exposed to ALAN developed obesity, and hepatic steatosis, which was paralleled by decreased expression of Rev-erbα and up-regulation of its lipogenic targets ACL and FAS in liver. Furthermore, the expression of Rev-erbα-targeting miRNAs, miR-140-5p, 185-5p, 326-5p and 328-5p were increased in this group. Consistently, overexpression of these miRNAs in primary hepatocytes reduced Rev-erbα expression at the mRNA and protein levels. Importantly, overexpression of Rev-erbα-targeting miRNAs increased mRNA levels of Acly and Fasn.ConclusionThus, altered miRNAs profile is an important mechanism underlying the disruption of the peripheral clock caused by exposure to ALAN, which could lead to hepatic steatosis. 相似文献
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83.
ObjectivesDiabetes is a major cause of hospitalization and in-hospital mortality. However, a scoring system that can be used to identify diabetic patients at risk of diabetes-related hospitalization and in-hospital mortality is lacking.MethodsWe included 32,653 patients in this retrospective cohort study. All recruited patients had type 2 diabetes, were 30–84 years of age, and were enrolled in the National Diabetes Care Management Program over the period of 2001–2003. We used the Cox proportional hazard regression model to derive risk scores. The predictive accuracy of the models was evaluated using receiver operating characteristic curves. We conducted the Hosmer–Lemeshow test to assess the agreement between predicted and observed risks.ResultsOver a follow-up period of eight years, 6243 patients were hospitalized for diabetes-related events, and 2048 deaths were registered in hospital records. For the one-, three-, five-, and eight-year periods, the areas under the curve (AUC) for diabetes-related hospitalization in the validation set were 0.80, 077, 0.76, and 0.74, respectively. The corresponding values for in-hospital mortality in the validation set were 0.87, 080, 0.77, and 0.76. The goodness-of-fit test showed that the predicted and observed probabilities in the one-, three-, five-, and eight-year periods were similar for diabetes-related hospitalization and in-hospital mortality in the validation set (all p values > 0.05).ConclusionWe developed models for the estimation of the risks of diabetes-related hospitalization and in-hospital mortality in patients with type 2 diabetes. The models may be used to identify diabetic patients who are at high risk for hospital admission and in-hospital mortality. 相似文献
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86.
《Radiography》2014,20(4):356-362
This paper reports the evaluation of a European funded 3-week summer school which took place in 2013 involving 60 staff and students from five universities. The evaluation looked at one group in detail using a qualitative approach to consider whether students and teachers can work together in multicultural groups in order to achieve their goal.MethodOne group was observed during 2 two-hour sessions of group activity; at the beginning and end of the summer school task. Video data was analysed using the Rapport Management framework, a model of cross-cultural communication, to determine what motivated this group's interactions.ResultsAs the group's deadline became imminent ‘face-threatening acts’ (FTAs) were more apparent. These were tolerated in this group because of the development of a strong social bond. There was inequity in participation with members of the group falling into either high- or low-involvement categories. This was also well-tolerated but meant some students may not have gained as much from the experience. The group lacked guidance on managing group dynamics.ConclusionCultural differences in communication were not the main threat to multi-cultural working groups. Potential problems can arise from failing to provide the group with a framework for project and team management. An emphasis on ground rules and the allocation of formal roles is important as is the encouragement of socialisation which supports the group during challenging times. 相似文献
87.
PurposeAlthough ductal carcinoma in situ (DCIS) seldom involves lymph nodes, some patients may upstage to invasive disease, thus requiring a second surgery for sentinel lymph node (SLN) biopsy (SLNB). However, the indications of SLNB remain inconclusive and clinical trials are rarely available. Our aim is to systematically review the real-world data to evaluate whether SLNB is precisely applied in patients with a high risk of upstaging from DCIS to invasive carcinoma.MethodsPubMed, EMBASE, and Cochrane library databases were searched. Prospective and retrospective cohort studies that evaluated the pathological outcomes of SLNB and the upstaging rate in women with DCIS were included. The primary outcomes were the upstaging and SLN-positive rates of patients initially diagnosed as having DCIS. We analyzed factors, namely biopsy methods, clinical presentations, histological patterns, and hormone receptor status, that potentially indicate nodal involvement risk.ResultsWe retrieved 43 prospective and 69 retrospective studies including 44,001 patients. The pooled estimates of upstaging and SLN-positive rates were 25.8% (95% confidence interval [CI]: 0.230–0.286) and 4.9% (95% CI: 0.042–0.055), respectively. In subgroup analysis, the upstaging rate was significantly higher in patients with estrogen receptor-negative status, palpable mass, tumor size >2 cm on imaging, and high-nuclear grade and those who received a preoperative diagnosis through core needle biopsy.ConclusionThe upstaging and SLN-positive rates of DCIS were 25.8% and 4.9%, respectively. By selecting patients with high risk DCIS, surgeons may increase the precision of and reduce the excess and incomplete treatment rates of SLNB. 相似文献
88.
ObjectiveTo evaluate a prospective association between physical activity (PA) and bone mineral density (BMD) in young adults.MethodTotal body (TB), lumbar spine (LS) and femoral neck (FN) BMD were measured in participants from the 1982 Pelotas Birth Cohort by dual-energy X-ray absorptiometry at 30 y. PA was evaluated at 15, 18 (males) and 23 y.Results3454 young adults were scanned (DXA) at least at one anatomical site. In males, PA at 15 y was associated with LS density (β = 0.061 g/cm2; 95% confidence interval (CI): 0.015; 0.108). A positive dose–response effect was found for the association between PA at 18 y and BMD. Males in the two highest quartiles of PA at 23 y had significantly greater BMD at all anatomical sites than males in the lowest quartile. We observed greater BMD at 30 y in boys who were active at least in one of the assessments (18 or 23 y) compared to inactive boys at both ages. Females in the highest quartile of PA at 23 y showed greater FN density at 30 y (β = 0.020; 95%CI: 0.001; 0.039).ConclusionsA physically active pattern is important to BMD across the first three decades of life. Potential beneficial effects of PA were not entirely lost with advancing age in male young adults. 相似文献
89.
《Journal of the American College of Radiology》2022,19(7):816-820
It seems inevitable that diagnostic and recommender artificial intelligence models will ultimately reach a point when they outperform human clinicians. Just as antibiotics displaced a host of medicinals for treating infections, the superior performance of such models will force their adoption. This article contemplates certain ethical and legal implications bearing on that adoption, especially because they involve a clinician’s exposure to allegations of malpractice. The article discusses four relevant considerations: (1) the imperative of using explainable artificial intelligence models in clinical care, (2) specific strategies for diminishing liability when a clinician agrees or disagrees with a model’s findings or recommendations but the patient nevertheless experiences a poor outcome, (3) relieving liability through legislation or regulation, and (4) comprehending such models as “persons” and therefore as potential defendants in legal proceedings. We conclude with observations on clinician–vendor relationships and argue that, although advanced artificial intelligence models have not yet arrived, clinicians must begin considering their implications now. 相似文献
90.
ObjectiveOf many instruments developed to assess Internet addiction, the Internet Addiction Test (IAT), an expanded version of the Internet Addiction Diagnostic Questionnaire (IADQ), has been the most widely used scale in English and non-English speaking populations. In this study, our aim was to investigate the psychometric properties of short and expanded versions of the IAT in a Turkish undergraduate sample.MethodOverall, 455 undergraduate students from Turkey aged between 18 and 30 participated in the study (63.53% were females). Explanatory and confirmatory factor analytic procedures investigated factor structures of the IADQ and IAT. The Internet Addiction Scale (IAS), Coping Inventory for Stressful Situations (CISS), Obsessive Compulsive Inventory—Revised (OCI-R) and Dissociative Experiences Scale (DES) were administered to assess convergent and divergent validities of the IADQ and IAT. Internal consistency and 15-day test–retest reliability were computed.ResultsIn the factorial analytic investigation, we found a unidimensional factor structure for each measure fit the current data best. Significant but weak to moderate correlations of the IADQ and the IAT with the CISS, OCI-R and DES provided empirical evidence for divergent validity, whereas strong associations with the subscales of the IAS pointed to the convergent validity of Young's Internet addiction construct. Internal consistency of the IADQ was weak (α = 0.67) and of the IAT was high (α = 0.93). Temporal reliability of both instruments was very high (α = 0.81 and α = 0.87; respectively).ConclusionThe IAT revealed promising and sound psychometric properties in a Turkish sample. 相似文献