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   6403篇
  免费   442篇
  国内免费   95篇
耳鼻咽喉   110篇
儿科学   182篇
妇产科学   88篇
基础医学   840篇
口腔科学   256篇
临床医学   520篇
内科学   1438篇
皮肤病学   214篇
神经病学   347篇
特种医学   397篇
外科学   935篇
综合类   40篇
预防医学   357篇
眼科学   161篇
药学   423篇
中国医学   64篇
肿瘤学   568篇
  2024年   8篇
  2023年   64篇
  2022年   136篇
  2021年   269篇
  2020年   156篇
  2019年   194篇
  2018年   235篇
  2017年   200篇
  2016年   280篇
  2015年   322篇
  2014年   347篇
  2013年   378篇
  2012年   571篇
  2011年   515篇
  2010年   327篇
  2009年   208篇
  2008年   367篇
  2007年   362篇
  2006年   319篇
  2005年   311篇
  2004年   275篇
  2003年   220篇
  2002年   188篇
  2001年   116篇
  2000年   111篇
  1999年   95篇
  1998年   33篇
  1997年   20篇
  1996年   18篇
  1995年   13篇
  1994年   18篇
  1993年   14篇
  1992年   25篇
  1991年   40篇
  1990年   18篇
  1989年   26篇
  1988年   21篇
  1987年   14篇
  1986年   12篇
  1985年   12篇
  1982年   6篇
  1981年   6篇
  1980年   6篇
  1979年   13篇
  1978年   4篇
  1974年   4篇
  1973年   5篇
  1972年   4篇
  1970年   4篇
  1966年   6篇
排序方式: 共有6940条查询结果,搜索用时 15 毫秒
81.
The aim the study was to determine the effect of SonoPrep? on the delivery and analgesic effects of EMLA? cream prior to intravenous (iv) cannulation in a tertiary pediatric emergency department. Children aged between 5 and 10?years were enrolled. Patients were randomized to receive either sonophoresis with SonoPrep? or sham sonophoresis followed by application of EMLA? cream for 5?min prior to iv cannulation. The primary outcome measurement was the child's rating of pain immediately after iv placement, using a 10-cm visual analog scale (VAS). Parents or guardians and blinded researchers were additionally asked to rate their perception of the child's pain using the 10-cm VAS and the Wong-Baker Face scale. A total of 42 patients completed the study (21 in the study group, 21 in the control group). The baseline characteristics between the groups were similar. The VAS pain score was significantly lower in children treated with sonophoresis compared with the sham sonophoresis (median (percentiles 25th-75th), 20.0 (10.0-22.5) vs. 60.0 (31.0-87.5); p?相似文献   
82.
Nitric oxide (NO) plays an important role in the regulation of upper respiratory function. Patients with untreated allergic rhinitis (AR) have an increased level of NO in the nasal cavity compared to normal individuals. We aimed to investigate serum levels of arginase and NO metabolites nitrite/nitrate in patients with AR during the symptomatic period. The patient and control groups consisted of 14 males and 12 females (mean age: 29, range: 20-40 years), and 10 males and 10 females (mean age: 27, range: 22-38 years), respectively. Nitrite/nitrate levels were 0.98 +/- 0.33 ng/ml in the patients with AR, and 0.78 +/- 0.26 ng/ml in the control group (p = 0.03). Arginase levels were 28.8 +/- 14.1 ng/ml in the patients with AR, and 20.8 +/- 13.5 ng/ml in the control group. The difference between the groups was statistically insignificant (p = 0.24). Our results support the view that NO plays an important role in the pathogenesis of AR, and NO metabolites may be used as a marker for monitoring the disease activity and therapy.  相似文献   
83.
白首乌化学成分的研究   总被引:11,自引:0,他引:11  
自白首乌主要品种耳叶牛皮消(Cynanchum auriculatum Royle ex Wight)根中首次分得三个已知甾体酯型甙元:告达亭(caudatin),开德甙元(kidjolanin),萝藦甙元(Metaplexigenin)和一种新的二苯酮衍生物(Ⅳ),经光谱分析推定其结构为2,6,2′,5′-四羟基,3-乙酰基,6′-甲基二苯酮,命名白首乌二苯酮。  相似文献   
84.
Despite the low prevalence of secondary bacterial infection in coronavirus disease 2019 (COVID-19) patients, most of them were administered antibiotic therapy empirically. However, the prognostic impact of empirical antibiotic therapy has not been evaluated. We conducted retrospective propensity score-matched case-control study of 233 COVID-19 patients with moderate to severe illnesses who required oxygen therapy and evaluated whether empirical antibiotic therapy could improve clinical outcomes. Empirical antibiotic therapy did not improve clinical outcomes including length of stay, days with oxygen requirement, the proportion of patients with increased oxygen demand, the proportion of patients who required mechanical ventilation, and overall mortality. This finding implies that routine administration of antibiotics for the treatment of COVID-19 is not essential and should be restricted.  相似文献   
85.
ObjectivesTo investigate and discuss the total-, lipid-associated, and thrombocyte-sialic acid levels in chronic heart failure (CHF) patients.Design and methodsThirty-one chronic heart failure patients and 38 healthy controls were included in the study. Serum total sialic acid (TSA), lipid associated sialic acid (LASA), thrombocyte sialic acid (TrSA) were determined together with the traditional inflammation and prognostic markers.ResultsSerum TSA levels were significantly higher in patient group (3.08 ± 0.33 mmol/L) than control group (2.60 ± 0.17 mmol/L). Serum LASA, homocysteine, high-sensitivity CRP, brain natriuretic peptide and erythrocyte sedimentation rate were also significantly higher in patient group. TrSA levels were not significant between the groups.ConclusionTSA and LASA levels increase in CHF, independent from coronary artery disease. TrSA levels were not found to be a prognostic or valuable marker for CHF patients. Acute phase response and lipid associated portions of SA are thought to be responsible for SA rise in CHF.  相似文献   
86.
The facial nerve connections and pathways from the cortex to the brainstem are intricate and complicated. The extra‐axial part of the facial nerve leaves the lateral part of the pontomedullary sulcus and enters the temporal bone through the internal acoustic meatus. In the temporal bone, the facial nerve branches into fibers innervating the glands and tongue. After it emerges from the temporal bone it supplies various facial muscles. It contains a motor, general sensory, special sensory, and autonomic components. The physician needs comprehensive knowledge of the anatomy and courses of the facial nerve to diagnose and treat lesions and diseases of it so that surgical complications due to facial nerve injury can be avoided. This review describes the microsurgical anatomy of the facial nerve and illustrates its anatomy in relation to the surrounding bone, connective, and neurovascular structures.  相似文献   
87.
88.
89.
90.
BACKGROUNDAn impalement injury of the oral cavity is a common traumatic injury in children. In most cases, it is not accompanied by sequelae, but if foreign body residues are not found due to a minor injury, they may result in inflammatory responses and delayed vascular injuries in the surrounding tissues. Without early diagnosis and appropriate initial management, residual foreign bodies can cause serious complications and even mortality in some cases. CASE SUMMARYA 9-year-old boy suffered an intra-oral injury by a wooden chopstick, and the patient was discharged from the hospital after receiving conservative treatment for the injury. However, the patient was readmitted to the hospital due to intra-oral bleeding, and since neck hematoma and right internal carotid artery pseudoaneurysm formation were detected on computed tomography, emergency surgery was performed. A remnant fragment of a wooden chopstick was found during the operation, and a delayed rupture of the internal carotid artery caused by the foreign body was also found.CONCLUSIONThe failure of early detection and diagnosis of a residual foreign body may result in delayed vascular rupture.  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