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   57118篇
  免费   4792篇
  国内免费   1456篇
耳鼻咽喉   220篇
儿科学   1085篇
妇产科学   1107篇
基础医学   5540篇
口腔科学   1088篇
临床医学   6590篇
内科学   11812篇
皮肤病学   394篇
神经病学   849篇
特种医学   743篇
外国民族医学   11篇
外科学   2718篇
综合类   7765篇
现状与发展   12篇
一般理论   1篇
预防医学   9490篇
眼科学   189篇
药学   7374篇
  13篇
中国医学   1633篇
肿瘤学   4732篇
  2024年   124篇
  2023年   786篇
  2022年   2059篇
  2021年   2635篇
  2020年   1996篇
  2019年   1985篇
  2018年   1964篇
  2017年   1914篇
  2016年   2216篇
  2015年   2533篇
  2014年   3968篇
  2013年   4783篇
  2012年   4075篇
  2011年   4271篇
  2010年   3221篇
  2009年   2973篇
  2008年   3077篇
  2007年   3002篇
  2006年   2591篇
  2005年   2141篇
  2004年   1784篇
  2003年   1402篇
  2002年   1107篇
  2001年   1005篇
  2000年   817篇
  1999年   669篇
  1998年   563篇
  1997年   539篇
  1996年   457篇
  1995年   357篇
  1994年   343篇
  1993年   253篇
  1992年   242篇
  1991年   201篇
  1990年   143篇
  1989年   146篇
  1988年   111篇
  1987年   121篇
  1986年   86篇
  1985年   122篇
  1984年   84篇
  1983年   51篇
  1982年   82篇
  1981年   62篇
  1980年   55篇
  1979年   43篇
  1978年   29篇
  1977年   39篇
  1976年   36篇
  1975年   26篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
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   
2.
IntroductionHip displacement is common in cerebral palsy (CP) and is related to the severity of neurological and functional impairment. It is a silent, but progressive disease, and can result in significant morbidity and decreased quality of life, if left untreated. The pathophysiology of hip displacement in CP is a combination of hip flexor-adductor muscle spasticity, abductor muscle weakness, and delayed weight-bearing, resulting in proximal femoral deformities and progressive acetabular dysplasia. Due to a lack of symptoms in the early stages of hip displacement, the diagnosis is easily missed. Awareness of this condition and regular surveillance by clinical examination and serial radiographs of the hips are the key to early diagnosis and treatment.Hip surveillance programmesSeveral population-based studies from around the world have demonstrated that universal hip surveillance in children with CP allows early detection of hip displacement and appropriate early intervention, with a resultant decrease in painful dislocations. Global hip surveillance models are based upon the patients’ age, functional level determined by the Gross Motor Function Classification system (GMFCS), gait classification, standardized clinical exam, and radiographic indices such as the migration percentage (MP), as critical indicators of progressive hip displacement.ConclusionDespite 25 years of evidence showing the efficacy of established hip surveillance programmes, there is poor awareness among healthcare professionals in India about the importance of regular hip surveillance in children with CP. There is a need for professional organizations to develop evidence-based guidelines for hip surveillance which are relevant to the Indian context.  相似文献   
3.
4.
Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy.  相似文献   
5.
Introduction: Percutaneous renal mass biopsy has evolved over the last decade with improvements on previous pitfalls including low tissue yield, high non-diagnostic rates, and complications. As understanding of tumor biology and natural history of renal cortical neoplasms has improved, percutaneous renal mass biopsy is poised to have an expanding role in an area characterized by individualized management and refined risk stratification.

Areas covered: This review summarizes the evolution of renal mass biopsy to its current state with respect to outcomes, indications, and clinical guidelines.

Expert opinion: With improved understanding of differential biological potential of renal cortical neoplasms combined with technical improvements in diagnostic yield and accuracy, utilization of renal mass biopsy is becoming an important adjunct to patient care in a broad range of clinical scenarios, including active surveillance, thermal ablation, and use of primary systemic therapy in localized and advanced settings.  相似文献   

6.
Among the chief limitations in achieving early detection and control of animal‐origin influenza of pandemic potential in high‐risk livestock populations is the existing lag time between sample collection and diagnostic result. Advances in molecular diagnostics are permitting deployment of affordable, rapid, highly sensitive, and specific point‐of‐capture assays, providing opportunities for targeted surveillance driving containment strategies with potentially compelling returns on investment. Interrupting disease transmission at source holds promise of disrupting cycles of animal‐origin influenza incursion to endemicity and limiting impact on animal production, food security, and public health. Adoption of new point‐of‐capture diagnostics should be undertaken in the context of promoting robust veterinary services systems and parallel support for operationalizing pre‐authorized plans and communication strategies that will ensure that the full potential of these new platforms is realized.  相似文献   
7.
目的 了解铜陵市人民医院2017年临床分离细菌对抗菌药物的耐药状况。方法 对2017年1-12月临床分离菌采用纸片扩散法(KB)进行药敏试验,按CLSI 2017年版标准判读药敏试验结果,采用WHONET 5.6软件进行数据分析。结果 临床分离细菌共3436株,其中革兰阳性菌719株,占20.9%;革兰阴性菌2717株,占79.1%。耐甲氧西林金黄色葡萄球菌(MRSA)和耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)的检出率分别为23.8%和72.3%,耐甲氧西林株对β-内酰胺类抗生素和其他测试抗菌药物的耐药率显著高于甲氧西林敏感株,未发现对万古霉素和替考拉宁耐药的葡萄球菌。粪肠球菌对青霉素、氨苄西林和呋喃妥因的耐药率较低,屎肠球菌对氯霉素的耐药率较低,5.3%屎肠球菌对万古霉素耐药。大肠埃希菌、克雷伯菌属(肺炎克雷伯菌和产酸克雷伯菌)和奇异变形菌中ESBLs的检出率分别为41.4%、50.7%和19.4%。肠杆菌科细菌中克雷伯菌属和沙雷菌属对碳青霉烯类抗生素耐药率较高,分别为37.5%和36.0%,其他菌属的耐药率低于3%。鲍曼不动杆菌对亚胺培南和美罗培南的耐药率分别80.3%和79.1%;铜绿假单胞菌对亚胺培南和美罗培南的耐药率分别为29.7%和28.4%。肺炎克雷伯菌、鲍曼不动杆菌和铜绿假单胞菌中广泛耐药株的检出率分别为31.3%(171/546)、0.6%(3/508)和0.7%(3/416)。结论 本院革兰阴性菌呈增多趋势,尤其广泛耐药的肺炎克雷伯菌应引起高度关注,做好细菌耐药性监测,加强临床抗菌药物的合理使用和医院感染控制。  相似文献   
8.
9.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  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