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   212733篇
  免费   30340篇
  国内免费   7140篇
耳鼻咽喉   1811篇
儿科学   1566篇
妇产科学   5212篇
基础医学   16310篇
口腔科学   2508篇
临床医学   17091篇
内科学   21038篇
皮肤病学   1395篇
神经病学   1552篇
特种医学   6197篇
外国民族医学   254篇
外科学   30939篇
综合类   27000篇
现状与发展   38篇
一般理论   3篇
预防医学   11544篇
眼科学   218篇
药学   14739篇
  131篇
中国医学   5267篇
肿瘤学   85400篇
  2024年   196篇
  2023年   4601篇
  2022年   6332篇
  2021年   10813篇
  2020年   10774篇
  2019年   9759篇
  2018年   9467篇
  2017年   9614篇
  2016年   10772篇
  2015年   12681篇
  2014年   17878篇
  2013年   17580篇
  2012年   14153篇
  2011年   14122篇
  2010年   10527篇
  2009年   10736篇
  2008年   10884篇
  2007年   10071篇
  2006年   8874篇
  2005年   7355篇
  2004年   6486篇
  2003年   5020篇
  2002年   4302篇
  2001年   3918篇
  2000年   3208篇
  1999年   2650篇
  1998年   2119篇
  1997年   2004篇
  1996年   1641篇
  1995年   1693篇
  1994年   1549篇
  1993年   1146篇
  1992年   1065篇
  1991年   994篇
  1990年   792篇
  1989年   680篇
  1988年   607篇
  1987年   448篇
  1986年   394篇
  1985年   471篇
  1984年   387篇
  1983年   254篇
  1982年   300篇
  1981年   252篇
  1980年   199篇
  1979年   140篇
  1978年   91篇
  1977年   78篇
  1976年   62篇
  1975年   43篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
61.
《Cancer cell》2022,40(8):835-849.e8
  1. Download : Download high-res image (220KB)
  2. Download : Download full-size image
  相似文献   
62.
63.
64.
Management of colorectal cancer (CRC) was severely affected by the changes implemented during the pandemic, and this resulted in delayed elective presentation, increased emergency presentation, reduced screening and delayed definitive therapy. This review was conducted to analyze the impact of the coronavirus disease 2019 (COVID-19) pandemic on management of CRC and to identify the changes made in order to adapt to the pandemic. We performed a literature search in PubMed, Medline, Index Medicus, EMBASE, SCOPUS, Reference Citation Analysis (https://www.referencecitationanalysis.com/) and Google Scholar using the following keywords in various combinations: Colorectal cancer, elective surgery, emergency surgery, stage upgrading, screening, surveillance and the COVID-19 pandemic. Only studies published in English were included. To curtail the spread of COVID-19 infection, there were modifications made in the management of CRC. Screening was limited to high risk individuals, and the screening tests of choice during the pandemic were fecal occult blood test, fecal immunochemical test and stool DNA testing. The use of capsule colonoscopy and open access colonoscopy was also encouraged. Blood-based tests like serum methylated septin 9 were also encouraged for screening of CRC during the pandemic. The presentation of CRC was also affected by the pandemic with more patients presenting with emergencies like obstruction and perforation. Stage migration was also observed during the pandemic with more patients presenting with more advanced tumors. The operative therapy of CRC was altered by the pandemic as more emergencies surgeries were done, which may require exteriorization by stoma. This was to reduce the morbidity associated with anastomosis and encourage early discharge from the hospital. There was also an initial reduction in laparoscopic surgical procedures due to the fear of aerosols and COVID-19 infection. As we gradually come out of the pandemic, we should remember the lessons learned and continue to apply them even after the pandemic passes.  相似文献   
65.
目的了解乳腺癌患者癌因性疲乏(cancer-related fatigue, CRF)现状,并分析其影响因素。方法采用横断面调查方法,向乳腺癌患者发放调查问卷,按照IDC-10诊断标准判断是否存在CRF,根据Piper疲乏量表中文修订版(Revised Piper Fatigue Scale, RPFS)得分评价疲乏程度,调查乳腺癌患者CRF的发生情况,并分析其影响因素。结果1 192例患者完成了全部调查问卷,乳腺癌患者发生CRF为668例(占56.04%);以轻、中度疲乏为主,分别占23.95%、55.24%,其中感觉维度得分最高。单因素分析结果显示,文化程度、乳腺癌病程、肿瘤分期、化疗周期、疼痛、上肢水肿、白细胞减少、恶心呕吐、贫血、潮热盗汗、失眠与乳腺癌患者CRF的发生有关(P<0.05);多因素Logistic回归分析显示,乳腺癌肿瘤分期、疼痛、白细胞减少、恶心呕吐、潮热盗汗、失眠是CRF发生的危险因素(P<0.05),病程是其保护因素(P<0.05)。CRF认知调查显示,乳腺癌患者对CRF认知度低,医护人员对其宣教度低。结论乳腺癌患者发生CRF较为普遍,以轻、中度疲乏为主;乳腺癌肿瘤分期、疼痛、白细胞减少、恶心呕吐、潮热盗汗、失眠是影响患者CRF的危险因素;乳腺癌患者对CRF认知度低。  相似文献   
66.
67.
目的:探讨环状RNA hsa_circ_0006867在结直肠癌中的表达及其与临床病理因素的关系。方法:全转录组测序筛选结直肠癌中特异circRNAs表达谱,挑选出差异表达显著的hsa_circ_0006867,qRT-PCR检测54例结直肠癌组织及癌旁组织中hsa_circ_0006867表达情况,分析其表达水平与结直肠癌临床病理特征的相关性,ROC曲线分析hsa_circ_0006867在结直肠癌中的诊断价值。结果:测序获得circRNAs在结直肠癌中的差异表达谱,qRT-PCR验证hsa_circ_0006867在结直肠癌中表达下调(P<0.05)。其表达水平与肿瘤分化程度和远处转移有关(P<0.05)。ROC曲线显示hsa_circ_0006867诊断结直肠癌AUC为0.851(95%CI:0.775~0.927),当截断值为0.0146时,敏感度为88.46%(95%CI:0.770~0.946),特异度为73.08%(95%CI:0.598~0.832),差异具有统计学意义(P<0.001)。结论:hsa_circ_0006867在结直肠癌中表达下调,与相关临床病理特征密切联系,可作为潜在结直肠癌临床诊断指标。  相似文献   
68.
69.
70.

Background

Esophagectomy is a major surgical intervention and a cornerstone in the treatment of esophageal cancer. There is clinical experience that blood lactate concentration often is elevated in the period following esophagectomy, but the incidence and clinical consequences are sparsely studied.

Methods

We extracted data from all patients undergoing esophagectomy at Karolinska University Hospital 2016–2018, n = 153. Most were performed with minimally invasive technique, n = 130. Blood lactate values directly after surgery, highest value during the first night, and morning level on postoperative day one were recorded. Primary outcome was hospital length of stay and secondary outcome was a composite of postoperative infection, additional surgery, or intensive care during the hospital stay. Development of anastomotic leak was analyzed separately.

Results

Postoperative hyperlactatemia was common as 93% of patients had peak lactate concentration >1.6 mmol/L and 27% >3.5 mmol/L in the first night following operation. Median hospital length of stay was 14 days. Blood lactate showed a weak correlation to hospital stay and intensive care the morning following surgery, but not at arrival to postoperative ward. There were no statistical differences between those with and without anastomotic leak at any of the time points. Elevated lactate in the first 12–16 h postoperatively was related to surgical factors (open technique, surgery time, and perioperative bleeding) but not to patient related factors (ASA-class, Charlson comorbidity index, sex, age) or cumulative fluid balance.

Conclusion

In conclusion, elevated blood lactate in the immediate time following esophagectomy showed a weak association to intensive care and length of stay but not anastomotic leak.  相似文献   
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