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2.
目的:探讨非体外循环心脏不停跳冠状动脉搭桥术的安全性和早期临床效果。方法:自2000年7月至2002年3月51例冠心病患接受冠状动脉搭桥手术,按手术方式分为非体外循环组(n=21)和传统体外循环组(n=30)。将两组病人的术前临床资料,手术方式,术后并发症和疗效等进行对比分析。结果:两组术前临床资料无明显差异。非体外循环组手术时间,术后出血输血量,呼吸机辅助时间显少于体外循环组,并且术后心律失常的发生率明显降低(P均<0.05),其他重要器官的并发症发生率亦低于体外循环组。两组平均随访9.6个月,心绞痛均消失,心功能改善,活动量明显增加。结论:非体外循环冠状动脉搭桥术是安全可行的,并发症少,近期疗效满意。  相似文献   
3.
讨论了强酸、强碱中和过程PH控制方案。以0.9mol/L的NaoH中和0.9mol/L的HNO3,流量增量为0.1-0.3kg/min,用模糊控制将PH控制在各要求的值上,ΔpH≤0.2,获得满意的结果。  相似文献   
4.
A previously developed eigenvector formalism is adapted to off-resonance in the transient response of quasiperiodic steady-state free precession (SSFP) sequences, including TrueFISP as a special case. The effective relaxation rates for essentially parallel and perpendicular deviations from the steady state are determined analytically in leading order perturbation theory. The latter are a known cause of oscillatory artifacts and therefore constitute the main target of a variety of preparation techniques. In addition, the former also play a dominating role in applications such as inversion recovery (IR) TrueFISP, which intentionally measure far away from the equilibrium. For both components, the approach toward equilibrium turns out to depend sensitively on field inhomogeneities, especially for smaller ratios of T2/T1. For the perpendicular deviations, the calculations show that--except very close to banding artifacts, where the steady-state signal is almost zero--field inhomogeneities additionally increase their effective relaxation rate almost as much as in the free induction decay (FID). The analytical results are tested against numerical simulation and MR measurements.  相似文献   
5.
The origin of image artifacts in an off-resonance spin-locking experiment is shown to be imperfections in the excitation flip angle. A pulse sequence for off-resonance spin locking is implemented that compensates for imperfections in the excitation flip angle through an off-resonance rotary echo. The off-resonance rotary echo alternates the frequency offset and phase of the RF transmitter during two spin-locking pulses of equal duration. The underlying theory is detailed, and MR images demonstrate the effectiveness of the technique in agarose gel phantoms and in in vivo human brain at 3T.  相似文献   
6.
Sleep in shift work has been studied extensively in regular shift systems but to a lesser degree in irregular shifts. Our main aim was to examine the sleep-wake rhythm in shift combinations ending with the night or the morning shift in two irregular shift systems. Three weeks' sleep/work shift diary data, collected from 126 randomly selected train drivers and 104 traffic controllers, were used in statistical analyses including a linear mixed model and a generalized linear model for repeated measurements. The results showed that the sleep-wake rhythm was significantly affected by the shift combinations. The main sleep period before the first night shift shortened by about 2 h when the morning shift immediately preceded the night shift as compared with the combination containing at least 36 h of free time before the night shift (reference combination). The main sleep period before the night shift was most curtailed between two night shifts, on average by 2.9 and 3.5 h among the drivers and the controllers, respectively, as compared with the reference combination. Afternoon napping increased when the morning or the day shift immediately preceded the night shift, the odds being 4.35-4.84 in comparison with the reference combination. The main sleep period before the morning shift became 0.5 h shorter when the evening shift preceded the morning shift in comparison with the sleep period after a free day. The risk for dozing off during the shift was associated only with the shift length, increasing by 17 and 35% for each working hour in the morning and the night shift, respectively. The results demonstrate advantageous and disadvantageous shift combinations in relation to sleep and make it possible to improve the ergonomy of irregular shift systems.  相似文献   
7.
行腹膜外剖宫产术时,在侧脐韧带与中脐韧带之间进行操作,不切断腹壁任何韧带,用撕拉、钝性剥离的方法分离膀胱与腹膜,子宫切口连续缝合两层,并将宫颈前筋膜与子宫切口浅层一并连续缝合.该方法不仅缩短了手术时间,避免了新生儿Apgar's低评分、新生儿窒息的发生,而且维持了腹壁结构的完整性,可进一步降低术后各种近、远期并发症的发生率.  相似文献   
8.
The choice of the most suitable surgical approach to the elbow forms the foundation of any successful elbow surgery. The surgical approach is based on the injury or pathology to be addressed and therefore specific anatomical details need to be considered. The surgeon must be comfortable with the bony, ligamentous and neurovascular anatomy of the elbow to consider and execute the best approach for each problem. This is an imperative to avoid iatrogenic injury.This article provides a detailed analysis, valuable technical tips, advantages and disadvantages of the most common approaches to the elbow. The lateral approaches include the Kocher, Kaplan and Extensor Digitorum Communis (EDC) Split approaches, the medial approaches include the Hotchkiss, Flexor carpi ulnaris (FCU) splitting approach, the Taylor and Scham approach. The anterior approach includes the anterior neurovascular interval approach and the posterior approaches include the Olecranon osteotomy, triceps sparing, triceps reflecting approach and finally the Boyd interval approach. The text and illustrations will provide a structured overview for the practicing surgeon.  相似文献   
9.
高频手术电极集切割、电凝和止血等作用于一体,能快速实现组织的离断、消融与闭合,在临床中的应用越来越广泛。高频手术电极按施加的电流频率范围可以分为普通高频电极和射频电极。该文主要介绍高频手术电极的工作原理与分类,并结合国内外高频手术电极的研究现状,对其在外科手术中的应用进行综述,并对其发展进行展望。  相似文献   
10.
目的 :为了解外伤性嵌钝性脑疝的发生规律 ,认识天幕切开治疗嵌钝性脑疝的疗效 ,对术前确诊为脑疝的病例术中清除血肿后直接观察脑疝的嵌钝情况。方法 :对脑疝嵌钝者行天幕切开 ,观察其术后 GCS评分同时与既往临床资料上分析嵌钝性脑疝可能性较大、未切开天幕的病例进行对比。结果 :嵌钝性脑疝多发生在血肿量大 ,GCS评分低的病人。结论 :天幕切开可提高疗效。  相似文献   
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