全文获取类型
收费全文 | 2354篇 |
免费 | 124篇 |
国内免费 | 30篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 103篇 |
妇产科学 | 25篇 |
基础医学 | 578篇 |
口腔科学 | 77篇 |
临床医学 | 257篇 |
内科学 | 500篇 |
皮肤病学 | 113篇 |
神经病学 | 79篇 |
特种医学 | 266篇 |
外科学 | 169篇 |
综合类 | 48篇 |
预防医学 | 75篇 |
眼科学 | 34篇 |
药学 | 138篇 |
中国医学 | 1篇 |
肿瘤学 | 42篇 |
出版年
2018年 | 23篇 |
2016年 | 22篇 |
2015年 | 30篇 |
2014年 | 31篇 |
2013年 | 82篇 |
2012年 | 36篇 |
2010年 | 48篇 |
2009年 | 41篇 |
2008年 | 26篇 |
2007年 | 55篇 |
2006年 | 60篇 |
2005年 | 42篇 |
2004年 | 29篇 |
2003年 | 33篇 |
2002年 | 27篇 |
2001年 | 45篇 |
2000年 | 28篇 |
1999年 | 43篇 |
1998年 | 84篇 |
1997年 | 100篇 |
1996年 | 109篇 |
1995年 | 74篇 |
1994年 | 77篇 |
1993年 | 79篇 |
1992年 | 42篇 |
1991年 | 40篇 |
1990年 | 42篇 |
1989年 | 66篇 |
1988年 | 58篇 |
1987年 | 49篇 |
1986年 | 52篇 |
1985年 | 38篇 |
1984年 | 55篇 |
1983年 | 27篇 |
1982年 | 32篇 |
1981年 | 37篇 |
1980年 | 49篇 |
1979年 | 23篇 |
1978年 | 27篇 |
1977年 | 35篇 |
1976年 | 38篇 |
1975年 | 36篇 |
1972年 | 24篇 |
1970年 | 23篇 |
1965年 | 50篇 |
1964年 | 50篇 |
1963年 | 47篇 |
1962年 | 41篇 |
1961年 | 40篇 |
1960年 | 65篇 |
排序方式: 共有2508条查询结果,搜索用时 0 毫秒
991.
992.
MG Pinette J Kahn KL Gross JR Wax J Blackstone A Cartin 《The journal of maternal-fetal & neonatal medicine》2013,26(1):37-43
Objective: The American College of Obstetricians and Gynecologists (ACOG) revised its practice bulletin on vaginal birth after Cesarean (VBAC) in October 1998 and July 1999 to require the presence of a surgeon, anesthesiologist and operating personnel throughout the trial of labor for patients with prior Cesarean. This study measures the change in VBAC rates from 1998 to 2001 and examines possible reasons for this change.Study design: We examined birth certificate and hospital data in the State of Maine from 1998 to 2001. Hospital-specific rates for primary Cesareans, total Cesareans, repeat Cesareans and vaginal deliveries after previous Cesarean were obtained. Additionally, we surveyed current obstetric-care providers in Maine regarding reasons for change in VBAC rates at their institutions.Results: VBAC rates declined by over 50% from 30.1 to 13.1%. The total Cesarean rate climbed from 19.4 to 24.0%. The most commonly reported reason for decrease in VBAC varied depending on whether a practitioner's hospital met ACOG guidelines.Conclusion: A marked decline in VBAC occurred after the change in ACOG vaginal birth after Cesarean policy. Multiple factors have contributed to this decline, including patients refusing VBAC after counseling and inability of institutions to meet ACOG guidelines. 相似文献
993.
Background
Physicians who hold medical disability assessment interviews (social insurance physicians) are probably influenced by stereotypes of claimants, especially because they have limited time available and they have to make complicated decisions. Because little is known about the influences of stereotyping on assessment interviews, the objectives of this paper were to qualitatively investigate: (1) the content of stereotypes used to classify claimants with regard to the way in which they communicate; (2) the origins of such stereotypes; (3) the advantages and disadvantages of stereotyping in assessment interviews; and (4) how social insurance physicians minimise the undesirable influences of negative stereotyping. 相似文献994.
丁燕 南娟 刘谦 周清华 陈军 Sarah TEMIN William PAO Timothy ALIFF Julie BRAHMER David H.JOHNSON Gregory MASTERS Daniel MILTON Luke NORDQUIST David G.PFISTEK Joan H.SCHILLER Reily SMITH Thomas J.SMITH John R.STRAWN David TRENT 《中国肺癌杂志》2010,13(3)
本文旨在为Ⅳ期非小细胞肺癌患者的治疗提供更新版推荐.本文资料检索源自2002年以来公布的相关随机试验文献.此指南范围限于化疗与生物治疗.更新委员会对这些文献进行了总结并提供了推荐更新.162篇文献符合标准被纳入参考.本推荐基于可改善总生存期的治疗方法.仅改善无进展生存期的治疗方法推动了对毒性及生存质量的监测.对于体力状态评分为0分或1分患者的一线治疗,可推荐以铂类为基础的细胞毒性药物的两药联用.对铂类治疗有禁忌的患者,可采用非铂类细胞毒性两药联合.对于体力状态评分为2分的患者,单一细胞毒性药物即可.对于疾病进展或经过4个周期的治疗仍对治疗无反应的患者,应停止一线细胞毒性化疗.即使在6个周期后患者对治疗仍有反应,亦应停止两药细胞毒性化疗.对于伴有明确的表皮生长因子受体(epidermal growth factor receptor,EGFR)突变的患者,可推荐一线采用吉非替尼治疗;对于EGFR突变为阴性或不明确的患者,细胞毒性化疗更佳.除具有特定临床特征的患者外,可推荐贝伐单抗与卡铂-紫杉醇联用.对于通过免疫组化证实EGFR阳性的肿瘤患者,可推荐西妥昔单抗与顺铂-长春瑞滨联用.多西紫杉醇、厄洛替尼、吉非替尼或培美曲塞被推荐作为二线治疗.对于未曾接受过厄洛替尼或吉非替尼治疗的患者,可推荐厄洛替尼作为三线治疗.现有数据不足以推荐常规三线采用细胞毒性药物.已有的证据也不足以推荐常规应用分子标记物选择化疗. 相似文献
995.
S Burillo‐Sanz MT Vargas RM Morales‐Camacho T Caballero‐Velázquez J Sánchez JR García‐Lozano I Pérez de Soto C Prats‐Martín R Bernal JA Pérez‐Simón 《Hematological oncology》2017,35(4):894-899
Ring 21 is an unstable structural abnormality of chromosome 21 that can lead to RUNX1 gene amplification. We present a unique case with a carrier patient of a constitutional ring chromosome 21 (partial monosomy and trisomy 21) with dysmorphic features and congenital malformations phenotype, who developed acute myeloid leukaemia with myelodysplasia‐related changes and two ring 21 chromosomes with RUNX1 amplification. The patient's constitutional ring 21 chromosome showed alterations in tumour suppressor genes, and oncogenes, but not in RUNX1. RUNX1 gene expression at acute myeloid leukaemia diagnosis, showed no upregulation, so other genes may also be the genetic amplification targets in this patient. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
996.
Relationship between plasma bilirubin level and oxidative stress markers in HIV‐infected patients on atazanavir‐ vs. efavirenz‐based antiretroviral therapy 下载免费PDF全文
997.
Luis M Franco Thomy de Ravel Brett H Graham Stephanie M Frenkel Jozef Van Driessche Pawel Stankiewicz James R Lupski Joris R Vermeesch Sau Wai Cheung 《European journal of human genetics : EJHG》2010,18(2):258-261
Genomic rearrangements are an increasingly recognized mechanism of human phenotypic variation and susceptibility to disease. Sotos syndrome is characterized by overgrowth, macrocephaly, developmental delay and advanced osseous maturation. Haploinsufficiency of NSD1, caused by inactivating point mutations or deletion copy number variants, is the only known cause of Sotos syndrome. A recurrent 2 Mb deletion has been described with variable frequency in different populations. In this study, we report two individuals of different ethnic and geographical backgrounds, with duplications reciprocal to the common Sotos syndrome deletion. Our findings provide evidence for the existence of a novel syndrome of short stature, microcephaly, delayed bone development, speech delay and mild or absent facial dysmorphism. The phenotype is remarkably opposite to that of Sotos syndrome, suggesting a role for NSD1 in the regulation of somatic growth in humans. 相似文献
998.
Nanae Tsuchiya Edwin JR van Beek Yoshiharu Ohno Hiroto Hatabu Hans-Ulrich Kauczor rew Swift Jens Vogel-Claussen J rgen Biederer James Wild Mark O Wielp tz Mark L Schiebler 《World journal of radiology》2018,10(6):52-64
Pulmonary contrast enhanced magnetic resonance angiography (CE-MRA) is useful for the primary diagnosis of pulmonary embolism (PE). Many sites have chosen not to use CE-MRA as a first line of diagnostic tool for PE because of the speed and higher efficacy of computerized tomographic angiography (CTA). In this review, we discuss the strengths and weaknesses of CE-MRA and the appropriate imaging scenarios for the primary diagnosis of PE derived from our unique multi-institutional experience in this area. The optimal patient for this test has a low to intermediate suspicion for PE based on clinical decision rules. Patients in extremis are not candidates for this test. Younger women (< 35 years of age) and patients with iodinated contrast allergies are best served by using this modality We discuss the history of the use of this test, recent technical innovations, artifacts, direct and indirect findings for PE, ancillary findings, and the effectiveness (patient outcomes) of CE-MRA for the exclusion of PE. Current outcomes data shows that CE-MRA and NM V/Q scans are effective alternative tests to CTA for the primary diagnosis of PE. 相似文献
999.
Rogerio S Parra Julio MF Chebli Heda MBS Amarante Cristina Flores Jose ML Parente Odery Ramos Milene Fernandes Jose JR Rocha Marley R Feitosa Omar Feres Antonio S Scotton Rodrigo B Nones Murilo M Lima Cyrla Zaltman Carolina D Goncalves Isabella M Guimaraes Genoile O Santana Ligia Y Sassaki Rogerio S Hossne Mauro Bafutto Roberto LK Junior Mikaell AG Faria Sender J Miszputen Tarcia NF Gomes Wilson R Catapani erson A Faria Stella CS Souza Rosana F Caratin Juliana T Senra Maria LA Ferrari 《World journal of gastroenterology : WJG》2019,25(38):5862-5882
BACKGROUND Inflammatory bowel diseases(IBD) have been associated with a low quality of life(QoL) and a negative impact on work productivity compared to the general population.Information about disease control,patient-reported outcomes(PROs),treatment patterns and use of healthcare resources is relevant to optimizing IBD management.AIM To describe QoL and work productivity and activity impairment(WPAI),treatment patterns and use of healthcare resources among IBD patients in Brazil.METHODS A multicenter cross-sectional study included adult outpatients who were previously diagnosed with moderate to severe Crohn's disease(CD) or ulcerative colitis(UC).At enrolment,active CD and UC were defined as having a Harvey Bradshaw Index≥8 or a CD Activity Index≥220 or calprotectin 200 μg/g or previous colonoscopy results suggestive of inadequate control(per investigator criteria) and a 9-point partial Mayo score≥5,respectively.The PRO assessment included the QoL questionnaires SF-36 and EQ-5 D-5 L,the Inflammatory Bowel Disease Questionnaire(IBDQ),and the WPAI questionnaire.Information about healthcare resources and treatment during the previous 3 years was collected from medical records.Chi-square,Fisher's exact and Student's t-/Mann-Whitney U tests were used to compare PROs,treatment patterns and the use of healthcare resources by disease activity(a=0.05).RESULTS Of the 407 patients in this study(CD/UC:64.9%/35.1%,mean age 42.9/45.9 years,54.2%/56.6% female,38.3%/37.1% employed),44.7%/25.2% presented moderate-to-severe CD/UC activity,respectively,at baseline.Expressed in median values for CD/UC,respectively,the SF-36 physical component was 46.6/44.7 and the mental component was 45.2/44.2,the EQ-visual analog scale score was 80.0/70.0,and the IBDQ overall score was 164.0/165.0.Moderate to severe activity,female gender,being unemployed,a lower educational level and lower income were associated with lower QoL(P 0.05).Median work productivity impairment was 20% and 5% for CD and UC patients,respectively,and activity impairment was 30 %,the latter being higher among patients with moderate to severe disease activity compared to patients with mild or no disease activity(75.0% vs 10.0%,P 0.001).For CD/UC patients,respectively,25.4%/2.8% had at least one surgery,38.3%/19.6% were hospitalized,and 70.7%/77.6% changed IBD treatment at least once during the last 3 years.The most common treatments at baseline were biologics(75.3%)and immunosuppressants(70.9%) for CD patients and 5-AS A compounds(77.5%) for UC patients.CONCLUSION Moderate to severe IBD activity,especially among CD patients,is associated with a substantial impact on QoL,work productivity impairment and an increased number of IBD surgeries and hospitalizations in Brazil. 相似文献
1000.