全文获取类型
收费全文 | 11886篇 |
免费 | 1347篇 |
国内免费 | 90篇 |
专业分类
耳鼻咽喉 | 129篇 |
儿科学 | 464篇 |
妇产科学 | 119篇 |
基础医学 | 734篇 |
口腔科学 | 454篇 |
临床医学 | 1585篇 |
内科学 | 2819篇 |
皮肤病学 | 66篇 |
神经病学 | 1379篇 |
特种医学 | 188篇 |
外科学 | 633篇 |
综合类 | 651篇 |
一般理论 | 2篇 |
预防医学 | 2526篇 |
眼科学 | 92篇 |
药学 | 625篇 |
8篇 | |
中国医学 | 124篇 |
肿瘤学 | 725篇 |
出版年
2024年 | 71篇 |
2023年 | 522篇 |
2022年 | 672篇 |
2021年 | 890篇 |
2020年 | 829篇 |
2019年 | 942篇 |
2018年 | 748篇 |
2017年 | 720篇 |
2016年 | 653篇 |
2015年 | 527篇 |
2014年 | 710篇 |
2013年 | 1351篇 |
2012年 | 551篇 |
2011年 | 513篇 |
2010年 | 406篇 |
2009年 | 415篇 |
2008年 | 426篇 |
2007年 | 366篇 |
2006年 | 297篇 |
2005年 | 238篇 |
2004年 | 196篇 |
2003年 | 175篇 |
2002年 | 169篇 |
2001年 | 136篇 |
2000年 | 102篇 |
1999年 | 86篇 |
1998年 | 84篇 |
1997年 | 74篇 |
1996年 | 64篇 |
1995年 | 37篇 |
1994年 | 47篇 |
1993年 | 34篇 |
1992年 | 41篇 |
1991年 | 36篇 |
1990年 | 26篇 |
1989年 | 22篇 |
1988年 | 14篇 |
1987年 | 12篇 |
1986年 | 21篇 |
1985年 | 16篇 |
1984年 | 14篇 |
1983年 | 6篇 |
1982年 | 17篇 |
1981年 | 9篇 |
1980年 | 6篇 |
1979年 | 5篇 |
1978年 | 7篇 |
1977年 | 6篇 |
1975年 | 7篇 |
1967年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
目的 :探讨青年及老年人原发性肝癌的临床特点。方法 :对 95例年龄≤ 3 9岁的青年肝癌和 112例年龄≥ 60岁的老年肝癌患者进行临床分析。结果 :(1)青年组HBV感染率为 92 .63 % ,其中HBsAg(+ )为 84.2 1% ,明显高于老年组的 62 .5 0 % ,P <0 .0 1。 (2 )青年组合并肝硬化者达 72 .63 % ,高于老年组的 5 4.46% ,P <0 .0 1。 (3 )青年组肝区疼痛症状明显高于老年组 ,前者以弥散型和巨块型多见 ,而后者则以单个局限为主。 (4)青年组甲胎蛋白 [AFP(+ ) ]为 67.3 7% ,老年组为 46.43 % ,P <0 .0 5。 (5 )老年组AKP、γ GT明显高于青年组 ,心脑血管合并症亦多于青年组 ,P <0 .0 1。结论 :青年肝硬化患者是原发性肝癌最重要的高危因素 ,应对这些患者长期追踪观察以早期发现和诊断。老年肝病患者AFP阳性率低 ,当其出现AKP、γ GT值升高时 ,应高度警惕肝癌。 相似文献
52.
Rafael Walker-Santiago Jason D. Tegethoff William M. Ralston James A. Keeney 《The Journal of arthroplasty》2021,36(2):653-656
BackgroundRevision total knee arthroplasty (rTKA) rates are increasing in younger patients. Few studies have assessed outcomes of initial aseptic rTKA performed for younger patients compared with traditional-aged patients.MethodsA detailed medical record review was performed to identify patient demographics, medical comorbidities, surgical rTKA indications, timing from index TKA to rTKA, subsequent reoperation rates, component rerevision rates, and salvage procedures for 147 young patients (158 knees) aged 55 years and younger and for a traditional older cohort of 276 patients (300 knees) between 60 and 75 years. Univariate analysis was performed to assess differences in these primary variables, and a log-rank test was used to estimate 5-year implant survival based on either reoperation or component revision and salvage procedures.ResultsYounger TKA patients were more likely to undergo initial aseptic rTKA within 2 years of their primary TKA (52.5% vs 29.0%, P < .001) and were more likely to undergo early reoperation (17.7% vs 9.7%, P = .02) or component rerevision (11.4% vs 6.0%, P < .05) after rTKA. Infection and extensor mechanism complications were more commonly noted in younger patients. Estimated 5-year survival was also lower for both reoperation (59.4% vs 65.7%, P = .02) and component rerevision or salvage (65.8% vs 80.1%, P = .02).ConclusionEarly reoperation and component re-rTKA were performed nearly twice as often in younger rTKA than traditional-aged TKA patients. Care should be given to reduce perioperative infection and extensor mechanism failures after rTKA in younger patients. 相似文献
53.
Chris A. Anthony Marcin K. Wasko Gail E. Pashos Robert L. Barrack Ryan M. Nunley John C. Clohisy 《The Journal of arthroplasty》2021,36(7):2518-2522
BackgroundComplications and patient-reported outcomes (PROs) of total hip arthroplasty (THA) in patients with Legg-Calve-Perthes disease (LCPD) have demonstrated variable results. The purpose of this study was to use a validated grading scheme to analyze complications associated with THA in patients with residual LCPD deformities. Second, we report PROs and intermediate-term survivorship in this patient population.MethodsA retrospective, single-center review was performed on 61 hips in 61 patients who underwent THA for residual Perthes disease. Average patient age was 42 years and 26% of hips had previous surgery. Complications were determined and categorized using a validated grading scheme that included five grades based on the treatment required to manage the complication and on persistent disability. PROs were compared from preoperative to most recent follow-up time points.ResultsMajor complications (grade III) occurred in three patients (5%) which each required a second surgical intervention. The most common minor grade I or II complications (11.5%) were asymptomatic heterotopic ossification (3.3%). Patients were lengthened on the surgical side an average of 1.4 cm with no nerve palsies. All patient PROs improved from preoperative to postoperative time points with the modified Harris Hip Score improving from 46.9 preoperatively to 85.4 postoperatively (P < .01). Patients free from revision for any reason at final follow-up (5.6 years; range 2-13 years) was 98.4% with one patient needing a revision of their femoral component.ConclusionsTHA for the sequelae of the LCPD has an acceptable complication rate and provides excellent patient reported outcomes at mid-term follow-up. 相似文献
54.
Zeyad T. Sahli Joseph K. Canner Martha A. Zeiger Aarti Mathur 《American journal of surgery》2021,221(2):478-484
BackgroundThe aim of this study was to evaluate the association between age and disease specific mortality (DSM) among adults diagnosed with medullary thyroid cancer (MTC).MethodSurveillance, Epidemiology, and End Results (SEER-18) was used to analyze adult MTC patients stratified by age (18–64, 65–79, ≥80 years). Associations between patient demographics, tumor size, nodal status, metastatic disease, and extent of surgery on DSM was assessed with multivariable Cox regression.ResultsAmong 1457 patients with MTC, 1008 (69.2%) were younger adults, 371 (25.5%) older adults, and 78 (5.4%) were super-elderly. A significantly higher proportion of older adults and super-elderly had less than the recommended operation for MTC. On multivariable analysis, older adults and super-elderly were 2.9 and 6.7 times more likely to have an increased DSM (HR:2.91, 95% CI: 1.83–4.63; p < 0.001 and HR: 6.70, 95%CI: 3.69–12.20; p < 0.001). Extent of surgery or lymphadenectomy did not affect DSM.ConclusionsIncreased age is an independent predictor of DSM in patients with MTC. 相似文献
55.
Eun L. Langman MD Cherie M. Kuzmiak DO Rachel Brader MD Samantha M. Thomas MB Sophia L. Alexander Sheila S. Lee MD Sheryl G. Jordan MD 《The breast journal》2021,27(8):657-663
The purpose of this study was to characterize presenting imaging findings in women younger than 40 diagnosed with invasive breast cancer in the context of pathology and clinical course. Retrospective chart and imaging reviews were performed in patients under 40 diagnosed with breast cancer between July 1, 2004, and December 31, 2013. Patient demographic, imaging, pathology, and clinical data were collected. Overall and recurrence-free survival were estimated using the Kaplan-Meier method. Univariate Cox proportional hazards models were performed to identify factors associated with recurrence-free survival. Our study cohort consisted of 110 patients with invasive mammary carcinoma. One hundred one (91.8%) presented with a palpable mass. The mean size of all lesions on imaging was 3.5 cm ± 2.9 cm. Malignant calcifications were present in 54 (49.1%) cases. Imaging demonstrated multifocal or multicentric disease in 45 (40.9%) cases. Seventy four (67.3%) cancers were high grade. Luminal genomic subtypes were the most common (n = 61, 55.5%). At presentation, 4 (3.6%) patients had bilateral malignancy and 8 (7.3%) patients had distant metastatic disease. Ninety seven (88.2%) underwent neoadjuvant chemotherapy and 67 (60.9%) underwent radiation therapy. Seventy five (68.2%) of the patients underwent mastectomy. The restricted mean time to recurrence was 9.01 years (standard error 3.162 months). ER positivity was associated with compromised recurrence-free survival. The overall survival rate was 0.962 at 10 years. Young patients diagnosed with breast cancer typically present with advanced breast imaging findings and undergo aggressive treatment. Recurrence often occurs >5 years from diagnosis, and ER positive subtypes are at increased risk for recurrence. 相似文献
56.
Jonathan Pruessmann Telja Pursche Friederike Hammersen Alexander Katalinic Dorothea Fischer Annika Waldmann 《Breast care (Basel, Switzerland)》2021,16(2):163
BackgroundBreast cancer in young women is associated with unfavourable tumour biology and is the main cause of death in this group. Conditional survival analysis estimates survival rates under the pre-condition of already having survived a certain time.ObjectivesTo describe conditional disease-free and overall survival of female breast cancer patients according to clinical subtypes and age.MethodsThis study analyses information from 1,858 breast cancer patients aged between 21 and 54 years, who were taking part in a post-therapeutic rehab programme (time between diagnosis and rehab start: maximum 24, median 11 months). Mean follow-up time was 3.6 years. We describe biological, clinical and pathological features in regard to different age groups (<40 and ≥40 years) and report conditional 5-year survival rates for overall and disease-free survival, and Cox proportional hazard models.ResultsVery young and young patients differed in regard to hormone receptor negativity, tumour grade, lymphovascular invasion, and molecular subtypes. Young women bore triple-negative and HER2-like disease more frequently. Conditional 5-year overall survival did not differ substantially between women <40 and 40–54 years of age (95 vs. 96%). It was highest for women with cancer of the luminal A subtype (98%) and lowest for the triple-negative subtype (91%). Lymphangiosis was a significant predictor of death. Results for disease-free survival were comparable.ConclusionsConditional 5-year overall survival after non-metastatic breast cancer was as high as 95.5%, and disease-free survival was 85.2%. When controlling for time between diagnosis and rehab start, molecular subtypes influenced overall and disease-free survival prospects. When additionally controlling for clinical characteristics, this effect only remained stable for disease-free survival. 相似文献
57.
《Health policy (Amsterdam, Netherlands)》2022,126(1):69-73
ObjectiveThe aim of this study is to compare health promotion policies (HPP) for older adults in four European countries: Germany, Italy, the Netherlands and Poland. We focus on the design, regulations and implementation of policies in these countries.MethodAs policy relevant information is mostly available in national languages we have approached experts in each country. They filled in a specially designed questionnaire on the design, regulation and implementation of health promotion policies. To analyze the data collected via questionnaires, we use framework analyses. For each subject we define several themes.ResultsRegarding regulations, Poland and Italy have a top-down regulation system for health promotion policy. Germany and Netherlands have a mixed system of regulation. Regarding the scope of the policy, in all four countries both health promotion and prevention are included. Activities include promotion of a healthy life style and social inclusion measures. In Poland and Italy the implementation plans for policy measures are not clearly defined. Clear implementation plans and budgeting are available in Germany and the NetherlandsConclusionsIn all four countries there is no document that exclusively addresses health promotion policies for older adults. We also found that HPP for older adults appears to be gradually disappearing from the national agenda in all four countries. 相似文献
58.
59.
《Vaccine》2021,39(37):5240-5250
Given our global interconnectedness, the COVID-19 pandemic highlights the urgency of building a global system that can support both routine and pandemic/epidemic adult immunization. As such, a framework to recommend vaccines and build robust platforms to deliver them to protect the rapidly expanding demographic of older adults is needed. Adult immunization as a strategy has the broad potential to preserve and improve medical, social, and economic outcomes, including maintaining functional ability that benefits older adults, their families, communities, and countries. While we will soon have multiple vaccines against COVID-19, we must recognize that we already have a variety of vaccines against other pathogens that can keep adults healthier. They can prevent simultaneous co-infection with COVID-19, and may favorably impact- the outcome of a COVID-19 illness. Further, administering a vaccine against COVID-19 requires planning now to determine delivery strategies impacting how older adults will be immunized in a timely manner. A group of international experts with various backgrounds from health and aging disciplines met to discuss the evidence case for adult immunization and crucial knowledge gaps that must be filled in order to implement effective policies and programs for older adult immunization. This group, coming together as the International Council on Adult Immunization (ICAI), outlined a high-level roadmap to catalyze action, provide policy guidance, and envision a global adult immunization platform that can be adapted by countries to fit their local contexts. Further meetings centered around the value of adult immunization, particularly in the context of COVID-19. There was agreement that programs to deliver existing influenza, pneumococcal, herpes zoster vaccines, and future COVID-19 vaccines to over a billion older adults who are at substantially higher risk of death and disability due to vaccine-preventable diseases are more urgent than ever before. Here we present a proposed framework for delivering routine and pandemic vaccines. We call upon the global community and governments to prioritize action for integrating robust adult immunization programs into the public health agenda. 相似文献