全文获取类型
收费全文 | 26154篇 |
免费 | 2080篇 |
国内免费 | 498篇 |
专业分类
耳鼻咽喉 | 480篇 |
儿科学 | 953篇 |
妇产科学 | 2009篇 |
基础医学 | 1187篇 |
口腔科学 | 566篇 |
临床医学 | 2568篇 |
内科学 | 3476篇 |
皮肤病学 | 319篇 |
神经病学 | 2608篇 |
特种医学 | 355篇 |
外国民族医学 | 4篇 |
外科学 | 5576篇 |
综合类 | 2746篇 |
一般理论 | 1篇 |
预防医学 | 1991篇 |
眼科学 | 414篇 |
药学 | 1701篇 |
20篇 | |
中国医学 | 227篇 |
肿瘤学 | 1531篇 |
出版年
2024年 | 62篇 |
2023年 | 578篇 |
2022年 | 1037篇 |
2021年 | 1404篇 |
2020年 | 1345篇 |
2019年 | 1366篇 |
2018年 | 1253篇 |
2017年 | 1197篇 |
2016年 | 1190篇 |
2015年 | 1089篇 |
2014年 | 2110篇 |
2013年 | 2286篇 |
2012年 | 1506篇 |
2011年 | 1568篇 |
2010年 | 1291篇 |
2009年 | 1198篇 |
2008年 | 1177篇 |
2007年 | 1104篇 |
2006年 | 1048篇 |
2005年 | 900篇 |
2004年 | 737篇 |
2003年 | 629篇 |
2002年 | 517篇 |
2001年 | 426篇 |
2000年 | 322篇 |
1999年 | 253篇 |
1998年 | 213篇 |
1997年 | 148篇 |
1996年 | 146篇 |
1995年 | 106篇 |
1994年 | 76篇 |
1993年 | 75篇 |
1992年 | 67篇 |
1991年 | 66篇 |
1990年 | 32篇 |
1989年 | 48篇 |
1988年 | 24篇 |
1987年 | 15篇 |
1986年 | 23篇 |
1985年 | 25篇 |
1984年 | 25篇 |
1983年 | 14篇 |
1982年 | 9篇 |
1981年 | 6篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
目的探讨妊娠合并右心感染性心内膜炎的临床特征、处理策略和母婴结局,为疾病的诊断和治疗提供理论依据。方法在中国知网、万方数据库、维普网、中国生物医学文献服务系统、PubMed、OVID、EMbase、ScienceDirect数据库检索相关文献,提取临床资料,分析妊娠合并右心感染性心内膜炎的临床表现、危险因素、赘生物位置、血培养结果、治疗策略和母婴结局等。结果纳入15篇文献,共18例患者。患者年龄为(27.7±4.8)岁,发病孕周为(27.8±6.9)周。发热(14例)、咳嗽(12例)、贫血(8例)、气短或呼吸困难(8例)是最常见的症状。心脏听诊时7例可闻及杂音,其中6例为收缩期杂音,1例未明确杂音类型,5例明确心脏听诊无杂音。9例合并肺栓塞和5例合并心力衰竭。危险因素主要为先天性心脏病(10/18)和静脉药瘾史(6/18)。赘生物附着位置以三尖瓣居多(10/18),其次为肺动脉瓣(4/18)。血培养阳性率高(15/16),主要包括葡萄球菌(9/15)及链球菌(3/15)。处理策略上,多以剖宫产适时终止妊娠,针对心内膜炎方面,在应用足量足疗程抗生素的基础上,11例患者行心脏手术,术式主要包括赘生物清除术、瓣膜修复或置换术以及先天性心脏病的手术等,根据患者的孕周、病情和心肺功能等具体情况决定手术在终止妊娠之前、之后或同期进行。18例患者全部存活,新生儿1例死亡(妊娠28周时行剖宫产分娩,因重度窒息死亡)。产妇随访情况基本良好。结论妊娠合并右心感染性心内膜炎临床少见且病情复杂,需及早诊断并实施个体化治疗方案。给予足量足疗程抗生素、选择合适的手术方案以及终止妊娠的时机,对于母婴结局具有重要意义。 相似文献
992.
目的探讨胎盘植入性疾病的危险因素及妊娠结局。 方法回顾性分析2009年1月至2017年12月广州医科大学附属第三医院/广州重症孕产妇救治中心围产资料数据库中信息完整的单胎妊娠孕妇48 650例临床资料,将这些孕妇分为胎盘植入性疾病组和非胎盘植入性疾病组,分析胎盘植入性疾病的危险因素及其妊娠结局。 结果单因素分析显示,年龄≥35岁、高中教育水平及以下、孕次≥3次、经产妇、人工流产史、剖宫产史、体外受精-胚胎移植受孕、合并前置胎盘是胎盘植入性疾病的相关危险因素(P<0.05)。多因素logistic回归分析显示,胎盘植入性疾病的独立危险因素为剖宫产史(OR=2.254,95%CI:1.917~2.650)、体外受精-胚胎移植受孕(OR=1.591,95%CI:1.212~2.089)、合并前置胎盘(OR=28.282,95%CI:24.338~32.866);与非胎盘植入性疾病产妇相比,患有胎盘植入性疾病产妇早产、剖宫产、产后出血、弥散性血管内凝血、产褥期感染、子宫切除、低出生体重儿、新生儿Apgar评分相对较低(1 min)、产妇入住重症监护病房的发生率明显升高(P<0.05)。 结论剖宫产史、辅助生殖受孕、合并前置胎盘是引起胎盘植入性疾病的独立危险因素,胎盘植入性疾病的妊娠结局不良。 相似文献
993.
子宫发育异常是女性生殖系统在胚胎6~20周间双侧副中肾管发育、融合和(或)吸收异常导致先天性子宫形态和功能异常的一系列表型谱。以纵隔子宫为代表的常见类型通常与反复流产、早产、胎位异常等产科并发症风险增加密切相关,但尚无足够证据支持其与原发不孕的相关性。除“无子宫”是明确的子宫性不孕因素外,其他类型的子宫发育异常往往均保有基本正常的生育力,在排除其他导致不孕的原因,且助孕失败的情况下再行子宫矫形术是审慎的做法。目前仅明确推荐对于反复流产和反复种植失败的患者施行宫腔镜子宫纵隔切除术。 相似文献
994.
基于社区获得性肺炎结局研究的思路转变,即强调具有临床意义的结局而不是简单依赖于生理或生物结局,应从短期的生物学终点朝向于远期终点的变化,着重从实验室检查结局(致病菌的清除和肺部病变吸收)、临床结局(死亡率、再住院率、住院的并发症、病情稳定时间、症状与体征、功能或生活质量等)和卫生经济学指标的结局(直接医疗和间接医疗方面等)等方面介绍社会获得性肺炎患者结局的现状,并对有关问题进行讨论. 相似文献
995.
Zi‐lin Sun 《Diabetes/metabolism research and reviews》2010,26(6):446-447
Damin and colleagues in this issue of DMRR Assessing quality of diabetes care and its variation in Aboriginal community health centres in Australia reviewed the quality of diabetes care and its variation among Aboriginal community health centres. They assessed partitioning of variation attributable to health centre and individual patient characteristics. The results demonstrated wide variation across different categories of diabetes care measures and across centres. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
996.
妊娠期糖尿病的临床治疗与妊娠结局的关系 总被引:3,自引:0,他引:3
目的探讨妊娠期糖尿病(GDM)的临床治疗,并分析与妊娠结局的关系。方法比较我院30例经收入院治疗的GDM孕妇和同期因各种原因未得以收入院治疗的GDM孕妇的临床资料,分析围生儿的并发症的发生及孕妇的分娩方式与对照组比较,并进行统计学分析。结果治疗组新生儿窒息、低血糖、围生儿死亡、巨大儿及分娩方式与对照组比较,差异有统计学意义(P〈0.05)。结论GDM应早期诊断和治疗,使血糖维持在正常水平是GDM治疗的关键,可以减少母婴并发症的发生。 相似文献
997.
Composite interference screws containing calcium phosphate for anterior cruciate ligament graft fixation could improve implant/bone integration and thereby reduced tunnelwidening and graft slippage. The present study investigated the effect of polylactate/hydroxyapatite interference screw (HA/PLLA) screw used for tibial graft fixation on tunnel widening and clinical outcomes compared with a metal interference screw. We hypothesized less tibial tunnelwidening with HA/PLLA screws compared to metal screws. Hundred patients with HA/PLLA screw tibial fixation was compared with 100 patients with metal screw tibial fixation. Tibial tunnel widening was measured on AP and lateral radiographs taken at 12 months follow-up. Clinical outcome was assessed by objective and subjective international Knee Documentation Committee (IKDC) scores, Noyes Sports Activity and Occupational Rating scores and KT-1000 knee laxity measurements. Tibial tunnel widening at the level of the metal screw group was 36% and 38% on AP and lateral radiographs respectively. Tunnel widening was lower in the HA/PLLA group with mean tunnel widening of 30% and 32% (p = 0.012 and 0.018) on AP and lateral radiographs respectively. No differences were found for any of the clinical scores or for anterior knee laxity. The use of a polylactate/hydroxyapatite interference screw resulted in less tibial tunnel widening than a metal screw around the screw but did not affect clinical outcome or objective knee laxity. 相似文献
998.
S. C. A. Chen D. Marriott E. G. Playford Q. Nguyen D. Ellis W. Meyer T. C. Sorrell M. Slavin the Australian Candidaemia Study 《Clinical microbiology and infection》2009,15(7):662-669
The risk factors for and clinical features of bloodstream infection with uncommon Candida spp. (species other than C. albicans, C. glabrata, C. parapsilosis, C. tropicals and C. krusei) are incompletely defined. To identify clinical variables associated with these species that might guide management, 57 cases of candidaemia resulting from uncommon Candida spp. were analysed in comparison with 517 episodes of Candida albicans candidaemia (2001–2004). Infection with uncommon Candida spp. (5.3% of candidaemia cases), as compared with C. albicans candidaemia, was significantly more likely to be outpatient-acquired than inpatient-acquired (15 of 57 vs. 65 of 517 episodes, p 0.01). Prior exposure to fluconazole was uncommon (n = 1). Candida dubliniensis was the commonest species (n = 22, 39%), followed by Candida guilliermondii (n = 11, 19%) and Candida lusitaniae (n = 7, 12%). C. dubliniensis candidaemia was independently associated with recent intravenous drug use (p 0.01) and chronic liver disease (p 0.03), and infection with species other than C. dubliniensis was independently associated with age <65 years (p 0.02), male sex (p 0.03) and human immunodeficiency virus infection (p 0.05). Presence of sepsis at diagnosis and crude 30-day mortality rates were similar for C. dubliniensis-related, non-C. dubliniensis-related and C. albicans-related candidaemia. Haematological malignancy was the commonest predisposing factor in C. guilliermondii (n = 3, 27%) and C. lusitaniae (n = 3, 43%) candidaemia. The 30-day mortality rate of C. lusitaniae candidaemia was higher than the overall death rate for all uncommon Candida spp. (42.9% vs. 25%, p not significant). All isolates were susceptible to amphotericin B, voriconazole, posaconazole, and caspofungin; five strains (9%) had fluconazole MIC values of 16–32 mg/L. Candidaemia due to uncommon Candida spp. is emerging among hospital outpatients; certain clinical variables may assist in recognition of this entity. 相似文献
999.
The aim of this study was to assess and compare uterine artery (UtA) blood flow volume in pregnant patients with an abnormal uterine Doppler pulsatility index (PI) who delivered fetuses with an appropriate weight for gestational age (AGA) or with intrauterine growth restricted (IUGR).We prospectively recruited singleton pregnancies with abnormal uterine arteries P.I. between 18 and 38 weeks of gestation regardless of estimated fetal weight (EFW). Vessel diameter and blood flow velocity were measured along the UtA upstream to the vessel bifurcation in both the right and left UtAs. Uterine blood flow volumes measured in these pregnancies were compared to historical Control-pregnancies. Forty-three patients delivered at term a normal weight newborn (AGA-pregnancies). Thirty patients delivered growth restricted newborns at 32 weeks (i.r. 29-36w) with a median weight of 1160 gr (i.r. 1000-2065 gr) (IUGR-pregnancies).At mid-gestation (18 + 0 − 25 + 6 weeks + days of gestation) a significantly lower uterine blood flow volume per unit weight was observed between the two study groups and compared to controls: 142 ml/min/kg in IUGR-pregnancies, 217 ml/min/kg in AGA-pregnancies and 538 ml/min/kg in Control-pregnancies. These striking differences in blood flow volume were already present at mid-gestation, at a time when EFW was still normal. In late gestation (27 + 0 − 37 + 6 weeks + days of gestation), pregnancies with an abnormal uterine P.I. showed persistently low UtA flow (<50% of controls) even when corrected for fetal weight: 81 ml/min/kg in IUGR-pregnancies, 105 ml/min/kg in AGA-pregnancies, and 193 ml/min/kg in Control-pregnancies; p < 0.0001.Our findings are consistent with other recent studies regarding the association between reduced uterine blood flow volume and fetal growth restriction. However, the study brings new insight into the finding of abnormal uterine P.I. in normally grown fetuses typically dismissed as “falsely abnormal” or “false positive” findings. Our study suggests that blood flow volume measurement may serve as a new tool to assess this group of patients and possibly those with ischemic placental diseases that may provide some basis for therapeutic interventions. 相似文献
1000.
目的:探讨生长激素(growth hormone,GH)在体外受精-胚胎移植(in vitro fertilization-em-bryo transfer,IVF-ET)治疗中对子宫内膜发育不良者子宫内膜及临床结局的影响。方法:IVF-ET患者共67例,均由于子宫内膜发育不良而致IVF-ET种植失败,再次行IVF-ET治疗时随机分为研究组(加用GH治疗,32例)和对照组(未使用GH治疗,35例),统计分析患者的临床结局。结果:患者Gn用量、平均获卵数、受精率、优质胚胎率组间无统计学差异(P>0.05);研究组子宫内膜厚度、形态及子宫内膜和内膜下血流均较对照组有明显改善(P<0.01);研究组的胚胎种植率(31.4%)及临床妊娠率(39.5%)明显高于对照组(15.7%和19.8%)(P<0.01),早期流产率明显减低(14.6%vs 21.4%)(P<0.01)。结论:对内膜发育不良的患者进行IVF-ET治疗时加用GH可能是通过改善子宫内膜对胚胎的容受性,从而提高胚胎种植率及临床妊娠率,降低早期流产率。 相似文献