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   338篇
  免费   22篇
  国内免费   24篇
儿科学   29篇
妇产科学   5篇
基础医学   25篇
口腔科学   8篇
临床医学   34篇
内科学   89篇
皮肤病学   5篇
神经病学   12篇
特种医学   44篇
外科学   36篇
综合类   40篇
预防医学   10篇
眼科学   5篇
药学   21篇
肿瘤学   21篇
  2022年   3篇
  2021年   2篇
  2020年   4篇
  2019年   4篇
  2018年   5篇
  2017年   5篇
  2016年   4篇
  2015年   7篇
  2014年   10篇
  2013年   13篇
  2012年   4篇
  2011年   5篇
  2010年   14篇
  2009年   17篇
  2008年   12篇
  2007年   21篇
  2006年   10篇
  2005年   5篇
  2004年   8篇
  2003年   13篇
  2002年   12篇
  2001年   15篇
  2000年   6篇
  1999年   6篇
  1998年   22篇
  1997年   19篇
  1996年   21篇
  1995年   9篇
  1994年   19篇
  1993年   11篇
  1992年   5篇
  1991年   6篇
  1989年   8篇
  1988年   14篇
  1987年   5篇
  1986年   7篇
  1985年   5篇
  1984年   6篇
  1983年   2篇
  1982年   5篇
  1981年   5篇
  1980年   5篇
  1978年   1篇
  1977年   2篇
  1976年   1篇
  1975年   1篇
排序方式: 共有384条查询结果,搜索用时 31 毫秒
31.
We report the case of a 29-year-old man with descending necrotizing mediastinitis and subcarinal spread secondary to oropharyngeal infection. The thoracic infection was treated by placement of a transcervical thoracic drain, which was removed 15 days after surgery. The outcome was satisfactory and no further invasive treatment was required. We believe that transcervical thoracic drainage is a useful initial treatment for descending necrotizing mediastinitis with subcarinal spread but no pleural cavity involvement.  相似文献   
32.
33.
Vein of Galen arteriovenous malformations encompass a diverse group of vascular anomalies that share a common feature: dilatation of the vein of Galen. Although clinical presentations are highly variable, depending on age of presentation, signs and symptoms overlap between age groups. The association of heart failure and cranial bruit constitutes the most striking clinical presentation in neonates. However, less severe and fulminant modes of presentation are frequent in older infants, children, and adults. Treatment approaches consist of symptomatic treatment of heart failure on the one hand and of surgery or endovascular treatment on the other. The results of the latter have improved in recent years, opening up a broad spectrum of new possibilities. We present the case of an asymptomatic 15-day-old neonate who presented an arteriovenous malformation of the vein of Galen and who was treated with endovascular occlusion of the arterial afferents. An excellent result was obtained with no evidence of neurological abnormalities.  相似文献   
34.
Objective  The performance of colposcopy provided in a screening study in five African countries was evaluated.
Design  Cross-sectional study.
Setting  Burkina Faso, Congo Brazzaville, Guinea Conakry, Mali and Niger.
Population  Women aged 25–59 years.
Methods  A total of 29 294 women participated in a cervical screening study in the five study sites, and newly trained local doctors performed colposcopy and directed biopsies as indicated. Using meta-analytical tools, four measures of colposcopy performance at different thresholds of colposcopic abnormalities were assessed. Sources of heterogeneity were also assessed.
Main outcome measures  Proportions of women receiving biopsies, adequate biopsies and women diagnosed with cervical intraepithelial neoplasia (CIN).
Results  Among 28 553 women with satisfactory colposcopy, 3101 had a colposcopic diagnosis of probable low-grade or worse lesions and 1128 probable high-grade or worse lesions. Overall, the measures that reached the set standards were proportion of biopsy taken at colposcopy threshold of probable high-grade or worse lesions (95%, 95% CI 90–100%) and proportion of adequate biopsy samples. The set standards were not met for the proportions of women diagnosed with CIN at different colposcopic abnormality thresholds. Detection of CIN2 or worse lesions increased with increasing colposcopic abnormality.
Conclusions  The performance of colposcopy in some of the African sites studied was comparable to that previously observed in other studies. With appropriate training, monitoring, continuing practice and quality assurance, adequate standards of colposcopy can be attained in sub-Saharan Africa.  相似文献   
35.
目的:建立家猪胸腰段脊髓火器贯通伤模型和改良Allen's打击伤后全瘫模型,观察伤后促凋亡基因p53基因的早期表达。方法:实验于2005-05/08在解放军第一七五医院实验室完成。取健康雄性家猪20只,单纯随机分为3组:①火器伤组:9只,在全麻状态下制作胸腰段(L1~L2)脊髓火器伤模型,分为伤后1,3,6h3个时间处死。②打击伤组:9只,L1节段脊髓行改良Allen’s打击,致伤力为500g·cm,处死时间同前。③空白对照组:2只,只麻醉,不造模,伤后6h处死。伤后不同时间点(伤后1,3,6h)和不同节段(伤点、近伤点、中伤点及远伤点)取材,采用SP法进行P53蛋白免疫组化染色,用TJTY-300型全自动图像分析仪测量P53免疫组织化学染色阳性物质吸光度。结果:经补充后20只猪进入结果分析。①脊髓损伤后3h打击伤组伤点,火器伤组近伤段脊髓P53蛋白的表达高于空白对照组(P<0.001),随着时间推移,打击伤组和火器伤组P53蛋白的表达呈升高趋势(P<0.001),且火器伤组要高于打击伤组(P<0.0001)。②在脊髓损伤后6h,打击伤组仅在伤点和近伤段P53蛋白的表达高于空白对照组(5.57±0.82,3.21±0.43,P<0.05),而火器伤组近伤段、中伤段及远段伤均高于空白对照组(6.46±0.66,4.27±0.39,1.16±0.17,P<0.05)。结论:①细胞凋亡基因p53在脊髓损伤中的表达有一定的时空性,在脊髓损伤后3h出现P53蛋白表达量的增加。②脊髓火器伤的波及范围较打击伤更为广泛。  相似文献   
36.
目的:探讨颈椎椎后肌肉组织Na -K -ATP酶活性变化与颈椎病的关系。资料来源:应用计算机检索PubMed1988-01/2004-12相关骨骼肌损伤与肌组织Na -K -ATP酶关系的文献,检索词“Na -K pump,Na -K -ATPase,muscle”,限定文献语言种类为English。同时计算机检索CNKI1990-01/2005-12相关Na -K -ATP酶与骨骼肌损伤的关系及颈椎病发病病因的文献,检索词“Na -K -ATP酶,骨骼肌,颈椎病病因”,限定文献语言种类为中文。资料选择:对资料进行初审,选取包括Na -K -ATP酶与肌组织损伤关系的文献,开始查找全文。纳入标准:Na -K -ATP酶活性变化与骨骼肌损伤密切相关的文献研究。排除标准:重复研究,Meta分析类文章。资料提炼:共检索到939篇关于Na -K -ATP酶与骨骼肌损伤相关方面的文献,最终纳入20篇符合标准的文献。资料综合:众多研究表明,Na 、K 与骨骼肌的兴奋、收缩、疲劳有密切关系,而Na -K -ATP酶又是调节细胞内外Na 、K 浓度必不可少的高分子蛋白,也就是说,骨骼肌一系列活动均离不开Na -K -ATP酶,Na -K -ATP酶活性变化与骨骼肌损伤是相互影响的。而强迫屈颈体位作为颈椎病发病的危险因素之一,可使颈椎椎后肌肉Na -K -ATP酶活性降低,酶活性降低致使肌细胞损伤,并最终导致骨骼肌损伤而发病。结论:以颈椎椎后肌肉酶活性的变化来阐释中医药对颈椎病确切疗效的相关研究未见,这有待于进一步研究,以充分展示中医药在颈椎病等相关疾病中的治疗优势。  相似文献   
37.

Background:

Neoadjuvant chemotherapy for potentially resectable metastatic colorectal cancer (MCC) is becoming a more common treatment algorithm. The aim of the present study was to evaluate the efficacy of precision hepatic arterial Irinotecan therapy in unresectable MCC.

Methods:

An open-label, multi-centre, multi-national single arm study of MCC patients, who received hepatic arterial irinotecan. Primary endpoints were safety, tolerance and metastatic tumour resection.

Results:

Fifty-five patients with metastatic colorectal to the liver underwent a total of 90 hepatic arterial irinotecan treatments. The extent of liver involvement was <25% in 75% of the patients (n= 41), between 26 and 50% in 15% of the patients (n= 11) and >50% in 10% of the patients (n= 24). The median number of hepatic lesions was four (range 1–20), with a median total size of all target lesions of 9 cm (range 5.5–28 cm) with 50% of patients having bilobar tumour distribution. The median number of irinotecan treatments was two (range 1–5). The median treatment dose was 100 mg (range 100–200) with a median total hepatic treatment of 200 mg (range 200–650). The majority of treatments (86%) were performed as lobar infusion treatments, and 30% of patients were treated with concurrent simultaneous chemotherapy. Eleven (20%) patients demonstrated significant response and downstage of their disease or demonstrated stable disease without extra-hepatic disease progression allowing resection, ablation or resection and ablation. There were no post-operative deaths. Post-operative complications morbidity occurred in 18% of patients, with none of them hepatic related. Non-tumorous liver resected demonstrated no evidence of steatohepatitis from the irinotecan arterial infusion.

Conclusions:

Hepatic arterial infusion irinotecan drug-eluting beads is safe and effective in pre-surgical therapy and helpful in evaluating the biology of metastatic colorectal cancer to the liver prior to planned hepatic resection.  相似文献   
38.

Introduction

Rectal polypectomy causes thinning (or even perforation) of the rectal wall in addition to thermic injury at the polypectomy site.

Case report

We present a rare case of spontaneous rectal perforation after uncomplicated nerve sparing endoscopic extraperitoneal radical prostatectomy in a patient with a previous history of rectal polypectomy at the perforation site. The patient could be treated conservatively. There was complete healing of the fistula without any effect on functional results. This Conservative therapy for such rectal perforations is indicated if the patient''s general condition remains stable without any signs of infection.

Conclusions

Polypectomy is an important risk factor for rectal perforation during nsEERPE. Adequate time interval should be given to allow healing and avoid adding further thermal wall damage which may obscure healing leading to complications like fistula. Conservative therapy for small missed rectal perforations constitutes an attractive, feasible and non invasive treatment entity. Following this principle we have not faced this complication in following similar cases.  相似文献   
39.
Amyloidosis is a systemic disease caused by extracellular accumulation of amyloid in different parts of the body. Pulmonary involvement is infrequent and nodular amyloidosis is extremely rare. We present the case of a 72-year-old man with chronic obstructive pulmonary disease in whom a 3-cm pulmonary nodule was discovered during routine radiological follow-up. After various complementary investigations failed to identify the etiology of the nodule, surgical excision was performed. Subsequent histopathological study revealed the presence of amyloid deposits with characteristic apple-green birefringence when stained with Congo-red under polarized light microscopy.  相似文献   
40.

Background  

Mandatory vaccination has contributed to the success of immunisation programmes but voluntary vaccination allows people to be responsible for their own health. There are benefits from both policies and the arguments between them remain subject to debate within and without the scientific community, both nationally and internationally. The aim of this study is to assess the opinions of those who actually work in the Vaccination Service.  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