全文获取类型
收费全文 | 36855篇 |
免费 | 3112篇 |
国内免费 | 844篇 |
专业分类
耳鼻咽喉 | 178篇 |
儿科学 | 663篇 |
妇产科学 | 191篇 |
基础医学 | 2121篇 |
口腔科学 | 464篇 |
临床医学 | 6356篇 |
内科学 | 12803篇 |
皮肤病学 | 198篇 |
神经病学 | 1499篇 |
特种医学 | 1619篇 |
外国民族医学 | 2篇 |
外科学 | 4238篇 |
综合类 | 4363篇 |
预防医学 | 1746篇 |
眼科学 | 1352篇 |
药学 | 2017篇 |
17篇 | |
中国医学 | 628篇 |
肿瘤学 | 356篇 |
出版年
2024年 | 105篇 |
2023年 | 796篇 |
2022年 | 1233篇 |
2021年 | 1775篇 |
2020年 | 1703篇 |
2019年 | 1617篇 |
2018年 | 1581篇 |
2017年 | 1283篇 |
2016年 | 1282篇 |
2015年 | 1332篇 |
2014年 | 2556篇 |
2013年 | 2570篇 |
2012年 | 1847篇 |
2011年 | 1932篇 |
2010年 | 1627篇 |
2009年 | 1599篇 |
2008年 | 1744篇 |
2007年 | 1633篇 |
2006年 | 1439篇 |
2005年 | 1310篇 |
2004年 | 1144篇 |
2003年 | 1073篇 |
2002年 | 837篇 |
2001年 | 799篇 |
2000年 | 632篇 |
1999年 | 582篇 |
1998年 | 553篇 |
1997年 | 478篇 |
1996年 | 423篇 |
1995年 | 350篇 |
1994年 | 299篇 |
1993年 | 278篇 |
1992年 | 264篇 |
1991年 | 229篇 |
1990年 | 229篇 |
1989年 | 183篇 |
1988年 | 165篇 |
1987年 | 166篇 |
1986年 | 132篇 |
1985年 | 146篇 |
1984年 | 158篇 |
1983年 | 136篇 |
1982年 | 115篇 |
1981年 | 96篇 |
1980年 | 63篇 |
1979年 | 61篇 |
1978年 | 78篇 |
1977年 | 39篇 |
1976年 | 37篇 |
1973年 | 28篇 |
排序方式: 共有10000条查询结果,搜索用时 26 毫秒
41.
J. M. Troyano M. T. Clavijo A. Gonzalez-Lorenzo I. Martí nez-Wallin O. Y. Marco P. S. Casas L. Martí nez-Cort s L. T. Merc J. Bajo-Arenas N. Hernandez D. Castro 《The Ultrasound Review of Obstetrics & Gynecology》2006,6(1):79-99
In order to assess the state and pathology of the woman's pelvis minor, a number of methods are commonly used among practitioners, encompassing clinical exploration, radiology, MRN, urodynamics, endoscopy and echography.
Echography has been poorly used in clinical pelvic exploration and its reliability is actually a matter of controversy 1. However, echographic surveys can provide us with valuable gynecological data on the state and pathologies of the soft pelvis, within the genital regions or even going beyond them, i.e. the rectal channel, bladder, urethra, anus, vascular plexuses, and all of their supporting tissues.
At our research unit, we have been employing Transvaginal Ultrasound echography (TVU) for a long time in conjunction with other pelvis-focused methods in order to study different kinds of pelvic alterations. TVU has proven to be friendly to use, fast, harmless and inexpensive, allowing serial explorations and producing high-quality dynamic images (loop-cinema, video-tape). Furthermore, this method is fairly aseptic in that the occurrence of faeces in the rectal ampolla is not a nuisance but a bonus in tracking the contours of the rectum walls and other topographical features which would be otherwise difficult to survey.
A complete pelvic floor TVU may add no longer than 5-8 minutes to a routine gynecological examination, can be implemented by the general gynecologist and generates data that can be further studied by the appropriate specialist for a more insightful evaluation 2. 相似文献
Echography has been poorly used in clinical pelvic exploration and its reliability is actually a matter of controversy 1. However, echographic surveys can provide us with valuable gynecological data on the state and pathologies of the soft pelvis, within the genital regions or even going beyond them, i.e. the rectal channel, bladder, urethra, anus, vascular plexuses, and all of their supporting tissues.
At our research unit, we have been employing Transvaginal Ultrasound echography (TVU) for a long time in conjunction with other pelvis-focused methods in order to study different kinds of pelvic alterations. TVU has proven to be friendly to use, fast, harmless and inexpensive, allowing serial explorations and producing high-quality dynamic images (loop-cinema, video-tape). Furthermore, this method is fairly aseptic in that the occurrence of faeces in the rectal ampolla is not a nuisance but a bonus in tracking the contours of the rectum walls and other topographical features which would be otherwise difficult to survey.
A complete pelvic floor TVU may add no longer than 5-8 minutes to a routine gynecological examination, can be implemented by the general gynecologist and generates data that can be further studied by the appropriate specialist for a more insightful evaluation 2. 相似文献
42.
目的 :应用多普勒组织成像 (DTI)技术检测二尖瓣环舒张期运动速度来评介原发性高血压左室舒张功能 ,探讨DTI的临床应用价值。方法 :2 0例原发性高血压和 2 0例年龄相似的健康者 ,应用DTI技术对二尖瓣环室间隔侧的运动速度进行测定 ,并与常规二尖瓣血流脉冲多普勒 (PW)检测结果对照分析。结果 :PW高血压组与对照组比较 ,峰值速度E、A及E/A明显低于对照组 ,差异显著 (P <0 0 1) ;DTI高血压组与对照组比较 ,峰值速度Ea、Aa及Ea/Aa明显低于对照组 ,差异非常显著 (P <0 0 0 1)。PW、DTI两组相同部位间比较 ,高血压组低于对照组。结论 :DTI技术评价高血压左室舒张功能比常规脉冲多普勒二尖瓣血流参数更敏感 相似文献
43.
提要本研究是在大鼠VD_3+Nicotine引起的心血管钙超载模型上观察心钠素(ANF)治疗(10ug ·kg~-1/d),对钙超载的影响。结果发现,钙超载组动物主动脉、心肌组织钙含量较对照组分别增高24倍(54.4±2.2vs 2.3±0.04fumol/gww)和9倍(16.9±2.1vs1.8±0.1umol/gww)。ANF治疗能显著抑制钙超载的发生,主动脉和心肌组织钙含量较钙超载组分别降低92%(3.8±0.4 umol/gww)和66%(5.6±0.6umol/gww)。离体滋流的钙超载血管环较对照组对去甲肾上腺素收缩反应增强;对乙酰胆碱舒张反应减弱,对硝普钠舒张反应无影响。ANF能显著改善钙超载所致的血管反应性障碍。实验结果表明,ANF具有显著的防治心血管钙超载的作用。 相似文献
44.
自1981年8月至1996年10月施行心脏直视手术1800例,发现永存左上腔静脉(PLSVC)11例,其中引入左心房1例。全部并发于其它心内畸形,且无特异体征。认为本中仔细探查是对PLSVC诊断的重要环节。本文对注意事项以及对不同类型的PLSVC引流入左房的外科处理方法进行了阐述。 相似文献
45.
实验性心包炎心钠素与内皮素变化及其临床意义 总被引:5,自引:1,他引:4
目的 研究实验性心包炎心钠素 (ANP)与内皮素 (ET)的变化 ,为临床诊治小儿心包炎提供实验依据。方法 家兔 2 4只 ,随机分为实验组 1 3只 ,在心包腔内注入 30 %尿素 (2ml/kg) ;对照组 1 1只 ,在心包腔内注入生理盐水 (2ml/kg)作为对照。注射前与注射后 1、4、7、1 0、1 5与 2 1d分别测定血浆ANP与ET。注射后2 1d测定心肌中ANP与ET ,同时切取心脏作病理与电镜检查。结果 注射后 1~ 1 0d血浆ANP和ET较注射前与对照组明显增高 (P <0 .0 5) ,注射后 1 5dANP下降 ,注射后 2 1d血浆与心肌中的ANP均较注射前与对照组明显下降 (P <0 .0 1 ) ,注射后 2 1d血浆与心肌ET则显著增高 (P <0 .0 1 )。届时心包病理与电镜检查示心包增厚 ,心肌萎缩与损害。结论 心包炎早期血浆ANP与ET均升高 ,说明心功能不全处于代偿期 ,应早期切开引流 ,心包炎后期血浆ANP下降而ET持续升高表示心包已增厚 ,心肌发生萎缩与损害 ,心功能处于失偿期 ,应及时行心包大部剥脱手术 ,解除心肌束缚 ,有望心功能得到恢复 相似文献
46.
左心室巨大室壁瘤不同左心室成形方法的对比研究 总被引:5,自引:3,他引:2
目的研究左心室巨大室壁瘤的左心室成形方法,对改进的左心室心内膜环缩技术和传统的线性缝合技术进行近、远期疗效对比。方法自1992年1月至2004年12月,对148例左心室巨大室壁瘤患者进行手术治疗,按照手术中左心室成形方法不同分为两组,传统术式组:89例,采用传统的线性缝合成形技术;改良术式组:59例,采用改良的心内膜环缩成形技术,旷置梗死的心肌组织,再缝合环缩后的切口。采用多次信访、电话随访和门诊复查相结合的方法对两组患者术后的近、远期疗效进行对比观察。结果手术死亡5例(3.4%),其中传统术式组4例,改良术式组1例(P=0.320)。术后主要并发症为低心排血量和心室颤动。随访134例(93.7%),随访时间51.4±27.0月。远期死亡21例,术后早期心功能Ⅲ级以上是影响远期死亡的危险因素(P=0.000)。改良术式组5年和8年生存率明显优于传统术式组(91.6%vs.76.3%,P=0.040;91.6%vs.61.4%,P=0.000)。两组心功能分级(NYHA)和左心室射血分数(LVEF)术后早期和随访期间较术前改善和升高(P<0.05),改良术式组改善更明显。两组左心室舒张期末内径(LVEDD)术后早期与术前比较明显减小(P=0.000),但随访30个月时有重新增大的趋势(P=0.046)。传统术式组随访30个月时LVEDD扩大比率明显高于改良术式组(38.8%vs.16.7%,P=0.030)。结论左心室巨大室壁瘤的手术近、远期疗效满意,保持适当的左心室形态和容积是手术的关键。心内膜环缩法进行左心室成形是一种简单有效的手段,其远期结果优于线性缝合法。 相似文献
47.
[目的]探讨在关节镜下膝关节后侧腔室联合手术入路的重要性和可操作性。[方法]经过前内侧、前外侧和股骨髁切迹以及后内侧、后外侧和后纵隔内切口联合入路分别入镜、入器械,进行膝关节后侧腔室的探查和手术操作。[结果]216例(239膝)应用联合入路探查和治疗,其中5例膝因关节僵硬操作失败;175例膝用于治疗后侧腔室疾病,膝关节后侧腔室手术视野显著改善,探查和手术操作完善,均达到手术目的。1例膝内侧隐神经不全损伤,没有腘后神经、腓总神经、腘后血管、交叉韧带等重要组织损伤。[结论]膝关节后侧腔室病变较多,是检查和治疗的重要部位,并非“技术盲区”。这种联合手术入路,手术风险低,具备可操作性,可以提高手术效率和质量,可作为膝关节镜下常规手术入路。 相似文献
48.
目的观察初诊T2DM短期胰岛素强化治疗的疗效。方法对40例初诊T2DM患者采用三餐前皮下注射短效胰岛素和睡前注射中效胰岛素2wk,并检测治疗2wk前后FPG、PPG、GHbA1C及血脂等值进行比较。结果两组治疗后FPG、PPG、GHbA1C及血脂各值均显著低于治疗前p〈0.05(x^2=4.940—11.544)。结论胰岛13细胞功能异常和(或)胰岛素抵抗是T2DM发病的基本环节,早期强化胰岛素治疗能获得血糖的有效控制,减少或延缓并发症的发生。 相似文献
49.
LI-FERN HSU PIERRE JAÏS MÉLÈZE HOCINI PRASHANTHAN SANDERS MARTIN ROTTER YOSHIHIDE TAKAHASHI CHRISTOPHE SCAVÉE FREDERIC SACHER JACQUES CLÉMENTY MICHEL HAÏSSAGUERRE 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S94-S98
The differentiation of pulmonary vein (PV) electrograms from atrial far-field signals during PV isolation (PVI) for atrial fibrillation (AF) may be difficult. In addition, owing to highly variable PV ostial sizes, current fixed-diameter circular PV mapping catheters may not yield optimal electrograms. We evaluated an expandable, circular 15–25 mm diameter, 20-pole mapping catheter for PV mapping during sustained AF in 25 patients. After selective PV angiography to define the ostial position and size, the catheter was introduced into each PV and withdrawn to the most stable proximal position, with optimal wall contact ensured by progressive loop expansion. At each PV ostium, electrograms recorded at high resolution (HR) were compared with those recorded at a resolution similar to that of a standard 10-pole Lasso catheter. After PVI performed during ongoing AF, the presence of residual far-field potentials (FFP) under both set-ups was compared. We mapped 97 PV, including 4 pairs with common ostia. In the HR recordings, the PV potentials had greater amplitude (0.5 ± 0.1 vs 0.3 ± 0.1 mV, P = 0.001) and fragmentation, whereas left atrial FFP were minimized. After successful isolation of all PV, FFP were observed in 33% of left superior and 28% of left inferior PV on the HR recordings, compared to 66% and 61%, respectively under normal resolution. Catheter stability and optimal wall contact, in combination with HR electrograms can optimize circumferential PV mapping during AF and improve the discrimination of FFP postablation. 相似文献
50.
BEATA WOAKOWSKA-KAPLON GRZEGORZ OPOLSKI† 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S110-S114
Atrial fibrillation (AF) may be associated with activation of atrial natriuretic peptide (ANP). The exact trigger for the release of ANP is still being debated. Atrial volume, pressure, and wall stretch are considered to be the main determinants of ANP activation. The aim of the study was to evaluate plasma ANP concentrations in patients with persistent AF and to analyze the echocardiographic determinants of ANP concentration in this group. The study population included 67 patients, 59 ± 7 years of age, with a median AF duration of 5.5 months (range 0.1–12). The relationship between plasma ANP concentrations and echocardiographic left atrial (LA) diameter and volume, and left ventricular (LV) diameter and ejection fraction (EF) was analyzed by logistic regression analysis. The median baseline plasma ANP concentration was 63 pg/mL (range 21–126) in the study group versus 34 pg/mL (range 16–73) in a control group. The mean left antero-posterior atrial dimension, LA volume, LV enddiastolic diameter, and LVEF were 48 mm, 104 mL, 52 mm, and 54%, respectively. A significant linear positive correlation was found between plasma ANP concentration and maximal LA volume (r = 0.62, P < 0.01). A negative correlation was found between LVEF and plasma ANP concentration (r =−0.42, P = 0.01). However, by multivariate regression analysis, no echocardiographic parameter was an independent predictor of plasma ANP concentration. Plasma ANP concentrations were independent of echocardiographic measurements of LA size or LV size and function in patients with persistent AF. 相似文献