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   31656篇
  免费   1712篇
  国内免费   92篇
耳鼻咽喉   432篇
儿科学   2262篇
妇产科学   762篇
基础医学   3487篇
口腔科学   610篇
临床医学   1821篇
内科学   6129篇
皮肤病学   1136篇
神经病学   1593篇
特种医学   1100篇
外科学   5142篇
综合类   1013篇
一般理论   12篇
预防医学   1471篇
眼科学   1371篇
药学   2654篇
中国医学   165篇
肿瘤学   2300篇
  2023年   189篇
  2022年   176篇
  2021年   850篇
  2020年   594篇
  2019年   710篇
  2018年   1010篇
  2017年   655篇
  2016年   888篇
  2015年   816篇
  2014年   1266篇
  2013年   1471篇
  2012年   2186篇
  2011年   2232篇
  2010年   1227篇
  2009年   1021篇
  2008年   1606篇
  2007年   1696篇
  2006年   1451篇
  2005年   1360篇
  2004年   1170篇
  2003年   1049篇
  2002年   925篇
  2001年   757篇
  2000年   715篇
  1999年   619篇
  1998年   240篇
  1997年   186篇
  1996年   147篇
  1995年   150篇
  1994年   123篇
  1993年   144篇
  1992年   388篇
  1991年   421篇
  1990年   358篇
  1989年   373篇
  1988年   322篇
  1987年   297篇
  1986年   283篇
  1985年   299篇
  1984年   230篇
  1983年   190篇
  1979年   248篇
  1978年   160篇
  1977年   157篇
  1976年   136篇
  1975年   165篇
  1974年   157篇
  1973年   178篇
  1972年   139篇
  1971年   123篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Tobacco smoking is associated with a substantially increased risk of postoperative complications. The peri-operative period offers a unique opportunity to support patients to stop tobacco smoking, avoid complications and improve long-term health. This systematic review provides an up-to-date summary of the evidence for tobacco cessation interventions in surgical patients. We conducted a systematic search of randomised controlled trials of tobacco cessation interventions in the peri-operative period. Quantitative synthesis of the abstinence outcomes data was by random-effects meta-analysis. The primary outcome of the meta-analysis was abstinence at the time of surgery, and the secondary outcome was abstinence at 12 months. Thirty-eight studies are included in the review (7310 randomised participants) and 26 studies are included in the meta-analysis (5969 randomised participants). Studies were pooled for subgroup analysis in two ways: by the timing of intervention delivery within the peri-operative period and by the intensity of the intervention protocol. We judged the quality of evidence as moderate, reflecting the degree of heterogeneity and the high risk of bias. Overall, peri-operative tobacco cessation interventions increased successful abstinence both at the time of surgery, risk ratio (95%CI) 1.48 (1.20–1.83), number needed to treat 7; and 12 months after surgery, risk ratio (95%CI) 1.62 (1.29–2.03), number needed to treat 9. More work is needed to inform the design and optimal delivery of interventions that are acceptable to patients and that can be incorporated into contemporary elective and urgent surgical pathways. Future trials should use standardised outcome measures.  相似文献   
2.
Treatment guidelines for management of uncomplicated gonorrhoeae have been recently modified owing to alarming upsurge in azithromycin resistance. This study investigated the prevalence and genetic determinants of gonococcal azithromycin resistance in India. Four (5.7%) of 70 gonococcal isolates were resistant to azithromycin. Of 16 isolates investigated for molecular mechanisms of resistance, 13 (81.3%) and 6 (37.5%) isolates exhibited mutations in coding and promoter regions of mtrR gene, respectively. However, ermA, ermB and ermC genes or mutations in rrl gene were absent in all isolates. Azithromycin resistance is low in India posing no immediate threat to use of dual-therapy for syndromic management.  相似文献   
3.
ObjectiveTo study the clinical features and identify unique renal neoplasia subtypes and their prognostic implications in individuals with tuberous sclerosis complex (TSC).Patients and MethodsThe Mayo Clinic nephrectomy registry included 37 patients with TSC diagnosed between 1970 and 2018. Four additional patients were identified from the pathology consultation and autopsy files. All available renal tumors were further characterized using immunohistochemistry and fluorescence in situ hybridization. Clinicopathologic features and follow-up were obtained from the medical record. The American Association for Cancer Research Project GENIE registry was accessed using cBioPortal for molecular profiling of angiomyolipoma (AML).ResultsA total of 276 renal tumors from 41 patients were analyzed. Renal tumors were classified into 9 distinct morphological subtypes, with AML predominating (238 [86%]). Interestingly, all these tumors acted in a benign fashion except one renal cell carcinoma with clear cells and fibromyomatous stroma and one epithelioid AML that metastasized. Molecular profiling studies revealed that epithelioid AMLs were enriched for alterations of TP53, RB1, and ATRX. Eight patients died of direct complications of TSC, including 3 of end-stage renal disease. To date, none have died of a renal epithelial neoplasm.ConclusionThe identification of unique renal neoplasia subtypes may provide important clues to establish a diagnosis of TSC, and in the somatic setting, this finding has important implications for accurate prognostication. These tumors tend to be indolent, and only 2 of 276 tumors in our study exhibited metastatic behavior. Our results support multidisciplinary management with a focus on preservation of renal function.  相似文献   
4.
5.
6.
7.
Tuberculosis in the tibial diaphysis following saphenous vein graft harvest for coronary artery bypass grafting has not been reported, to the best of authors’ knowledge. We report the first such clinical case in view of its clinical rarity and as a complication of the simple procedure like saphenous vein graft harvest.  相似文献   
8.
9.
Despite the remarkable technological advancement in the arena of critical care expertise, the mortality of critically ill patients remains high. When the organ functions deteriorate, goals of care are not fulfilled and life-sustaining treatment becomes a burden on the patient and caregivers, then it is the responsibility of the physician to provide a dignified end to life, control the symptoms of the patient and provide psychological support to the family members. Palliative care is the best way forward for these patients. It is a multidimensional specialty which emphasizes patient and family-based care and aims to improve the quality of life of patients and their caregivers. Although intensive care and palliative care may seem to be at two opposite ends of the spectrum, it is necessary to amalgamate the postulates of palliative care in intensive care units to provide holistic care and best benefit patients admitted to intensive care units. This review aims to highlight the need for an alliance of palliative care with intensive care in the present era, the barriers to it, and models proposed for their integration and various ethical issues.  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