收费全文 | 3899297篇 |
免费 | 280870篇 |
国内免费 | 9910篇 |
耳鼻咽喉 | 53969篇 |
儿科学 | 125504篇 |
妇产科学 | 107248篇 |
基础医学 | 547098篇 |
口腔科学 | 110971篇 |
临床医学 | 358234篇 |
内科学 | 757140篇 |
皮肤病学 | 90807篇 |
神经病学 | 318622篇 |
特种医学 | 148228篇 |
外国民族医学 | 1168篇 |
外科学 | 587837篇 |
综合类 | 84481篇 |
现状与发展 | 7篇 |
一般理论 | 1504篇 |
预防医学 | 301968篇 |
眼科学 | 90178篇 |
药学 | 285494篇 |
11篇 | |
中国医学 | 8173篇 |
肿瘤学 | 211435篇 |
2019年 | 30322篇 |
2018年 | 42573篇 |
2017年 | 32666篇 |
2016年 | 37509篇 |
2015年 | 42280篇 |
2014年 | 58845篇 |
2013年 | 88594篇 |
2012年 | 118123篇 |
2011年 | 125573篇 |
2010年 | 75176篇 |
2009年 | 71645篇 |
2008年 | 117388篇 |
2007年 | 124550篇 |
2006年 | 126538篇 |
2005年 | 122080篇 |
2004年 | 117232篇 |
2003年 | 112890篇 |
2002年 | 109461篇 |
2001年 | 186836篇 |
2000年 | 191718篇 |
1999年 | 161713篇 |
1998年 | 46528篇 |
1997年 | 41075篇 |
1996年 | 40955篇 |
1995年 | 39492篇 |
1994年 | 36182篇 |
1993年 | 33914篇 |
1992年 | 125732篇 |
1991年 | 121123篇 |
1990年 | 117644篇 |
1989年 | 113598篇 |
1988年 | 104481篇 |
1987年 | 102404篇 |
1986年 | 96103篇 |
1985年 | 92146篇 |
1984年 | 68926篇 |
1983年 | 58523篇 |
1982年 | 34399篇 |
1981年 | 30652篇 |
1979年 | 61724篇 |
1978年 | 43311篇 |
1977年 | 36831篇 |
1976年 | 33967篇 |
1975年 | 36100篇 |
1974年 | 43355篇 |
1973年 | 41351篇 |
1972年 | 38916篇 |
1971年 | 36178篇 |
1970年 | 33929篇 |
1969年 | 32207篇 |
Background
The optimal noninvasive test (NIT) for patients with diabetes and stable symptoms of coronary artery disease (CAD) is unknown.Objectives
The purpose of this study was to assess whether a diagnostic strategy based on coronary computed tomographic angiography (CTA) is superior to functional stress testing in reducing adverse cardiovascular (CV) outcomes (CV death or myocardial infarction [MI]) among symptomatic patients with diabetes.Methods
PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) was a randomized trial evaluating an initial strategy of CTA versus functional testing in stable outpatients with symptoms suggestive of CAD. The study compared CV outcomes in patients with diabetes (n = 1,908 [21%]) and without diabetes (n = 7,058 [79%]) based on their randomization to CTA or functional testing.Results
Patients with diabetes (vs. without) were similar in age (median 61 years vs. 60 years) and sex (female 54% vs. 52%) but had a greater burden of CV comorbidities. Patients with diabetes who underwent CTA had a lower risk of CV death/MI compared with functional stress testing (CTA: 1.1% [10 of 936] vs. stress testing: 2.6% [25 of 972]; adjusted hazard ratio: 0.38; 95% confidence interval: 0.18 to 0.79; p = 0.01). There was no significant difference in nondiabetic patients (CTA: 1.4% [50 of 3,564] vs. stress testing: 1.3% [45 of 3,494]; adjusted hazard ratio: 1.03; 95% confidence interval: 0.69 to 1.54; p = 0.887; interaction term for diabetes p value = 0.02).Conclusions
In diabetic patients presenting with stable chest pain, a CTA strategy resulted in fewer adverse CV outcomes than a functional testing strategy. CTA may be considered as the initial diagnostic strategy in this subgroup. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550) 相似文献Background
Nursing Home Compare (NHC) ratings, created and maintained by Medicare, are used by both hospitals and consumers to aid in the skilled nursing facility (SNF) selection process. To date, no studies have linked NHC ratings to actual episode-based outcomes. The purpose of this study was to evaluate whether NHC ratings are valid predictors of 90-day complications, readmission, and bundle costs for patients discharged to an SNF after primary total joint arthroplasty (TJA).Methods
All SNF-discharged primary TJA cases in 2017 at a multihospital academic health system were queried. Demographic, psychosocial, and clinical variables were manually extracted from the health record. Medicare NHC ratings were then collected for each SNF. For patients in the Medicare bundle, postacute and total bundle cost was extracted from claims.Results
Four hundred eighty-eight patients were discharged to a total of 105 unique SNFs. In multivariate analysis, overall NHC rating was not predictive of 90-day readmission/major complications, >75th percentile postacute cost, or 90-day bundle cost exceeding the target price. SNF health inspection and quality measure ratings were also not predictive of 90-day readmission/major complications or bundle performance. A higher SNF staffing rating was independently associated with a decreased odds for >75th percentile 90-day postacute spend (odds ratio, 0.58; P = .01) and a 90-day bundle cost exceeding the target price (odds ratio = 0.69; P = .02) but was similarly not predictive of 90-day readmission/complications.Conclusion
Results of our study suggest that Medicare's NHC tool is not a useful predictor of 90-day costs, complications, or readmissions for SNFs within our health system. 相似文献Materials and Methods: Relevant papers in PubMed published through June 2017 were selected to track updated information about PTL with an emphasis on diagnosis and novel therapeutic management.
Results: The most frequent cases include non-Hodgkin lymphoma derived from B-cells, mainly diffuse large B-cell lymphoma (DLBCL) followed by mucosa-associated lymphoid tissue (MALT) lymphoma or a mixed type. Other subtypes are less common. Lymphomas derived from T-cells and Hodgkin lymphomas are extremely rare. Hashimoto's autoimmune thyroiditis has been implicated as a risk factor for lymphoma. At the molecular level, the Wnt5a protein and its receptor Ror2 are involved in the course of the disease. Ultrasonography, fine needle aspiration (FNA) biopsy, and core or open biopsy combined with new diagnostic facilities contribute to an accurate diagnosis. An increased potential exists for a cure without the need for a radical surgical procedure. Modern chemoradiation therapy plus the monoclonal antibody rituximab, which acts against CD20, have limited the need for surgical interventions and provide an excellent outcome in most cases. However, some cases have resulted in treatment failure or recurrence.
Conclusions: A multidisciplinary approach must be used to define the management policy in each case. Future efforts by researchers are likely to be focused on the molecular level. 相似文献