首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   423917篇
  免费   31706篇
  国内免费   11743篇
耳鼻咽喉   5950篇
儿科学   9813篇
妇产科学   9616篇
基础医学   37371篇
口腔科学   11064篇
临床医学   43251篇
内科学   52141篇
皮肤病学   6436篇
神经病学   19248篇
特种医学   11936篇
外国民族医学   145篇
外科学   48835篇
综合类   66814篇
现状与发展   34篇
一般理论   29篇
预防医学   35907篇
眼科学   5560篇
药学   34491篇
  404篇
中国医学   31473篇
肿瘤学   36848篇
  2023年   6413篇
  2022年   9579篇
  2021年   15690篇
  2020年   15198篇
  2019年   20798篇
  2018年   18471篇
  2017年   15812篇
  2016年   13838篇
  2015年   13627篇
  2014年   25670篇
  2013年   26570篇
  2012年   23564篇
  2011年   25583篇
  2010年   20470篇
  2009年   19193篇
  2008年   18982篇
  2007年   19733篇
  2006年   17508篇
  2005年   15352篇
  2004年   12427篇
  2003年   10884篇
  2002年   8784篇
  2001年   7975篇
  2000年   6638篇
  1999年   5527篇
  1998年   4392篇
  1997年   4047篇
  1996年   3557篇
  1995年   3603篇
  1994年   3394篇
  1993年   2608篇
  1992年   2562篇
  1991年   2227篇
  1990年   1986篇
  1989年   1739篇
  1988年   1651篇
  1987年   1396篇
  1985年   4026篇
  1984年   4989篇
  1983年   3497篇
  1982年   3959篇
  1981年   3680篇
  1980年   3281篇
  1979年   3005篇
  1978年   2608篇
  1977年   1951篇
  1976年   2186篇
  1975年   1642篇
  1974年   1435篇
  1973年   1281篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Many environmental risk factors for hepatobiliary cancers are known but whether they are associated with specific cancer types is unclear. We present here a novel approach of assessing standardized incidence ratios (SIRs) of previously diagnosed comorbidities for hepatocellular carcinoma (HCC), gallbladder cancer (GBC), cholangiocarcinoma (CCA) and ampullary cancer. The 13 comorbidities included alcohol and nonalcohol related liver disease, chronic obstructive pulmonary disease, gallstone disease, viral and other kinds of hepatitis, infection of bile ducts, hepatic and other autoimmune diseases, obesity and diabetes. Patients were identified from the Swedish Inpatient Register from 1987 to 2018, and their cancers were followed from 1997 onwards. SIRs for HCC were 80 to 100 in men and women diagnosed with hepatitis C virus and they were also >10 in patients diagnosed with hepatitis B virus, other kind of hepatitis, hepatic autoimmune disease and nonalcohol related liver disease. Many of these risks, as well as alcohol related liver disease, were either specific to HCC or were shared with intrahepatic CCA. For GBC, CCA and ampullary cancer infection of bile ducts was the main risk factor. Gallstone disease, nonhepatic autoimmune diseases and diabetes were associated with all hepatobiliary cancers. The limitations of the study include inability to cover some rare risk factors and limited follow-up time. Many of the considered comorbidities are characterized by chronic inflammation and/or overt immune disturbance in autoimmune diseases. The results suggest that local chronic inflammation and a related immune disturbance is the carcinogenic trigger for all these cancers.  相似文献   
2.
3.
4.
徐素琴  向邱 《全科护理》2022,20(1):73-76
目的:探讨项目管理在降低呼吸重症监护室(RICU)环境物品表面多重耐药菌检出率中的应用效果。方法:采用目的抽样方法,选取医院呼吸与危重症医学科RICU 17张编制床位、32处高频接触环境物品表面及42名工作人员为观察对象。2019年1月—2019年3月实施RICU常规管理,2019年4月—2019年6月实施项目管理。比较项目管理前后RICU各类别工作人员手卫生依从率、RICU环境物品表面清洁合格率及多重耐药菌检出率。结果:在项目管理后RICU各类别工作人员手卫生依从率均高于项目管理前(P<0.05);项目管理后RICU环境物品表面清洁合格率较项目管理前升高(P<0.05);项目管理后多重耐药菌(MDRO)病人床单位及病区办公区域环境物体表面的耐甲氧西林金黄色葡萄球菌(MRSA)和耐碳青霉烯鲍曼不动杆菌(CRAB)检出率均较项目管理前降低(P<0.05)。结论:项目管理可有效提高RICU各类别工作人员手卫生依从性及环境物品表面清洁合格率,降低RICU环境物品表面多重耐药菌检出率。  相似文献   
5.
IntroductionDetailed data on clinical characteristics in children with the omicron strain of SARS-COV-2 are limited.MethodsWe conducted a retrospective observational study of children with COVID-19 at the National Center for Child Health and Development to evaluate the clinical manifestations during and before the emergence of the omicron variant. Only symptomatic patients without underlying diseases were included. Participants were divided into two temporal groups: the “omicron era” (1/2022–2/2022) and the “pre-omicron era,” where the delta variant predominated (7/2021–11/2021). The patients were subclassified into an older vaccine-eligible group (aged 12–17 years), a younger vaccine-eligible group (aged 5–11 years), and a vaccine-ineligible group (aged 0–4 years).ResultsWe compared 113 patients in the omicron era with 106 in the pre-omicron era. Most patients in both eras had non-severe disease, and no patients required mechanical ventilation or died. Among patients aged 0–4 years, sore throat and hoarseness were more common during the omicron era than the pre-omicron era (11.1% vs. 0.0% and 11.1% vs. 1.5%, respectively). Croup syndrome was diagnosed in all patients with hoarseness. Among patients aged 5–11 years, vomiting was more frequent during the omicron era (47.2%) than during the pre-omicron era (21.7%). Cough and rhinorrhea were less common during the omicron era in patients aged 0–4 and 5–11 years, respectively, than during the pre-omicron era.ConclusionsIn children with COVID-19, clinical manifestations differed between the omicron and pre-omicron eras. In the Omicron era, croup syndrome was more frequent in vaccine-ineligible children.  相似文献   
6.
The discussion paper will focus on continuity of care relating to previous NZ research, specifically to transitioning complex preterm infants from NICU to home based on parent experiences, and on the practice developments that have occurred, to ensure optimal health outcomes. Previous NZ research discovered parent desire a consistent service delivery for the entire transition journey from NICU and at home.An informative and comprehensive opportunity has occurred for reflective professional practice, evaluation, development and implementation which have transpired in positive change through innovative practice developments and support change implementation in Wellington, NZ. This has resulted in the articulation of a model of care that has both embraced and integrated parental desires for a continuity of care process for complex preterm infants. This has been achieved by having the same Discharge Facilitator/Key Case Manager present within the NICU and external to the NICU for Home-based infants for the entire transition journey.The paper will focus and emphasis additional practice development changes and furthermore, will present a real purpose, for other countries to learn of such practice developments that have exemplified a celebratory success for families of Wellington, NZ.  相似文献   
7.
8.
IntroductionThe aim of this study was to compare long-term patient reported outcomes (PROs) in patients with locally advanced extremity soft tissue sarcoma (eSTS) after isolated limb perfusion followed by resection (IR), compared to extended resection (ER), primary amputation (A) or secondary amputation after IR (IR-A).MethodsPatients were selected from the respondents of a multi-institutional cross-sectional cohort survivorship study (SURVSARC) conducted among sarcoma survivors registered in the Netherlands Cancer Registry (NCR), 2–10 years after diagnosis. Used PROs were the EORTC QLQ-C30, the Cancer worry scale (CWS), the Hospital Anxiety and Depression Scale (HADS), and the Toronto Extremity Salvage Score (TESS).ResultsWe identified 97 eSTS survivors: IR = 20, ER = 49, A = 20, IR-A = 8. While there were no differences in PROs between IR and ER, results showed better functioning and functionality in both groups versus the amputation groups. The amputation groups scored significantly lower on physical functioning (A = 62.7, IR-A = 65.7 versus IR = 78.0, ER = 82.7, p = 0.001) and role functioning (A = 67.5, IR-A = 52.8 versus IR = 79.2, ER = 80.6, p = 0.039), both EORTC QLQ-C30 scales. Also for the TESS, the scores were significantly lower for the amputation groups compared to the limb sparing groups (upper extremity p = 0.007 with A = 68.9, IR-A = 71.6 versus IR = 93.3, ER = 91.1; lower extremity p < 0.001 with A = 72.2, IR-A50.9 versus IR = 84.5 and ER = 85.5). There were no significant differences between the groups on cancer worry, anxiety and depression.ConclusionHRQoL in eSTS survivors treated with IR or ER is equal; for maintenance of physical functioning and functionality IR and ER outperform an amputation.  相似文献   
9.
BackgroundSurgical resection is recommended for patients with resectable acinar cell carcinoma (ACC). The aim of this study was to investigate the clinical characteristics and surgical outcomes of resectable ACC in comparison to pancreatic ductal adenocarcinoma (PDAC).MethodA retrospective analysis was performed on all patients who consecutively underwent radical resection with pathologically confirmed ACC and PDAC from December 2011 to December 2018. Clinicopathologic characteristics and follow-up information were analyzed. A 1:3 propensity score matching (PSM) method was used to minimize the bias between ACC and PDAC.ResultsA total of 26 patients with ACC and 1351 with PDAC were included. Compared to PDAC, ACC tended to be larger (4.5 vs. 3.0 cm; p < 0.001) and more frequently located in the pancreatic body/tail (61.5% vs. 36.6%, p = 0.009), with lower total bilirubin levels, lower neutrophil lymphocyte ratio (NLR) levels and lower carbohydrate antigen 19-9 (CA19-9) levels and carcinoembryonic antigen (CEA) levels. There was no difference in postoperative morbidities in patients with ACC and PDAC. The median OS and RFS were longer in ACC when compared to PDAC (OS: 43.5 mo vs. 19.0 mo, p = 0.004; RFS: 24.5 mo vs. 11.6 mo, p = 0.023). After the 1:3 PSM, ACC remained to be a better histological type for OS (p = 0.024), but had comparable RFS with PDAC (p = 0.164).ConclusionPatients with ACC after radical resection had better OS than that with PDAC. However, ACC is also an aggressive tumor with a similar trend of RFS with PDAC after the matching, necessitating the multidisciplinary treatment for resectable ACC disease.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号