全文获取类型
收费全文 | 11406篇 |
免费 | 823篇 |
国内免费 | 320篇 |
专业分类
耳鼻咽喉 | 43篇 |
儿科学 | 278篇 |
妇产科学 | 143篇 |
基础医学 | 968篇 |
口腔科学 | 106篇 |
临床医学 | 921篇 |
内科学 | 1195篇 |
皮肤病学 | 188篇 |
神经病学 | 620篇 |
特种医学 | 265篇 |
外科学 | 631篇 |
综合类 | 1156篇 |
一般理论 | 3篇 |
预防医学 | 1775篇 |
眼科学 | 318篇 |
药学 | 2285篇 |
13篇 | |
中国医学 | 1326篇 |
肿瘤学 | 315篇 |
出版年
2024年 | 39篇 |
2023年 | 299篇 |
2022年 | 434篇 |
2021年 | 599篇 |
2020年 | 602篇 |
2019年 | 709篇 |
2018年 | 613篇 |
2017年 | 516篇 |
2016年 | 341篇 |
2015年 | 323篇 |
2014年 | 911篇 |
2013年 | 774篇 |
2012年 | 826篇 |
2011年 | 874篇 |
2010年 | 588篇 |
2009年 | 505篇 |
2008年 | 550篇 |
2007年 | 520篇 |
2006年 | 395篇 |
2005年 | 279篇 |
2004年 | 260篇 |
2003年 | 227篇 |
2002年 | 147篇 |
2001年 | 124篇 |
2000年 | 126篇 |
1999年 | 82篇 |
1998年 | 70篇 |
1997年 | 72篇 |
1996年 | 54篇 |
1995年 | 46篇 |
1994年 | 53篇 |
1993年 | 38篇 |
1992年 | 43篇 |
1991年 | 43篇 |
1990年 | 30篇 |
1989年 | 17篇 |
1988年 | 26篇 |
1987年 | 18篇 |
1986年 | 17篇 |
1985年 | 69篇 |
1984年 | 60篇 |
1983年 | 30篇 |
1982年 | 38篇 |
1981年 | 28篇 |
1980年 | 25篇 |
1979年 | 27篇 |
1978年 | 18篇 |
1977年 | 18篇 |
1975年 | 18篇 |
1974年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
《Journal of pediatric surgery》2023,58(5):856-861
Background/PurposeA small number of Hirschsprung disease (HD) patients develop inflammatory bowel disease (IBD)-like symptoms after pullthrough surgery. The etiology and pathophysiology of Hirschsprung-associated IBD (HD-IBD) remains unknown. This study aims to further characterize HD-IBD, to identify potential risk factors and to evaluate response to treatment in a large group of patients.MethodsRetrospective study of patients diagnosed with IBD after pullthrough surgery between 2000 and 2021 at 17 institutions. Data regarding clinical presentation and course of HD and IBD were reviewed. Effectiveness of medical therapy for IBD was recorded using a Likert scale.ResultsThere were 55 patients (78% male). 50% (n = 28) had long segment disease. Hirschsprung-associated enterocolitis (HAEC) was reported in 68% (n = 36). Ten patients (18%) had Trisomy 21. IBD was diagnosed after age 5 in 63% (n = 34). IBD presentation consisted of colonic or small bowel inflammation resembling IBD in 69% (n = 38), unexplained or persistent fistula in 18% (n = 10) and unexplained HAEC >5 years old or unresponsive to standard treatment in 13% (n = 7). Biological agents were the most effective (80%) medications. A third of patients required a surgical procedure for IBD.ConclusionMore than half of the patients were diagnosed with HD-IBD after 5 years old. Long segment disease, HAEC after pull through operation and trisomy 21 may represent risk factors for this condition. Investigation for possible IBD should be considered in children with unexplained fistulae, HAEC beyond the age of 5 or unresponsive to standard therapy, and symptoms suggestive of IBD. Biological agents were the most effective medical treatment.Level of EvidenceLevel 4 相似文献
4.
5.
《Vaccine》2020,38(45):7118-7128
IntroductionToward the Global Vaccine Action Plan 2020 goal, almost 90% of countries have established a National Immunization Technical Advisory Group (NITAG). However, little is known about NITAG's contributions to governance.MethodsIn 2017–2018, a two-step, qualitative retrospective study was conducted. Jordan (JO), Argentina (AR), and South Africa (SA) were selected owing to government-financed NITAGs from middle-income countries (MICs), geographic diversity, and a vaccine introduction with NITAG support. Country case studies were developed, collecting data through desk review and face-to-face key informant interviews (KIIs) from Ministry of Health (MoH) and NITAG. Case studies were analyzed together, to assess governance applying the European Observatory on Health Systems and Policies framework focusing on transparency, accountability, participation, integrity, and policy capacity (TAPIC).ResultsDocument review and 53 KII (22 AR, 20 SA, 11 JO) showed NITAGs played a pivotal role as advisors promoting a culture of evidence-informed policies. NITAGs strengthened governance, although practices varied among countries. Meetings were conducted behind-closed-doors, participation restricted to members, only in one country agendas, and recommendations were public (AR). To increase participation, policy capacity, and transparency, countries considered adding experts in communications, advocacy, and economics. AR and SA contemplated including community members. NITAGs functioned autonomously from the government, with no established internal or external monitoring or supervision. NITAG meeting minutes allowed the review of integrity, adherence to terms of reference, standard operating procedures, and conflict of interest (CoI). For the most part, NITAGs abided by their mandates. Significant issues were related to the level of MoH support and oversight of CoI declaration and documentation.ConclusionsSystematically implementing governance approaches could improve processes, better tailor policies, and implementation. The long-term survival and resilience of NITAGs in these countries showed they play a significant role in strengthening governance. Lessons learned could be useful to those promoting country-driven evidence-informed decision-making. 相似文献
6.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
7.
8.
9.
《Journal of pediatric surgery》2023,58(6):1133-1138
PurposeThis study describes the job market from the perspective of recent pediatric surgery graduates.MethodsAn anonymous survey was circulated to the 137 pediatric surgeons who graduated from fellowships 2019–2021.ResultsThe survey response rate was 49%. The majority of respondents were women (52%), Caucasian (72%), and had a median student debt burden of $225,000. Considering job opportunities, respondents strongly emphasized camaraderie (93%), mentorship (93%), case mix (85%), geography (67%), faculty reputation (62%), spousal employment (57%), compensation (51%), and call frequency (45%). 30% were satisfied with the employment opportunities available, and 21% felt strongly prepared to negotiate for their first job. All respondents were able to secure a job. Most jobs were university-based (70%) or hospital employed (18%) positions where surgeons covered median of two hospitals. 49% wanted protected research time, and 12% of respondents were able to secure substantial, protected research time. The median compensation for university-based jobs was $12,583 below the median AAMC benchmark for assistant professors for the corresponding year of graduation.ConclusionThese data highlight the ongoing need for assessment of the pediatric surgery workforce and for professional societies and training programs to further assist graduating fellows in preparing to negotiate their first job.Type of studySurveyLevel of EvidenceLevel V. 相似文献
10.
Julia H. Vermylen Gordon J. Wood Elaine R. Cohen Jeffrey H. Barsuk William C. McGaghie Diane B. Wayne 《Journal of pain and symptom management》2019,57(3):682-687