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101.
目的:探讨肾石通颗粒联合盐酸坦洛新缓释胶囊治疗输尿管下段结石的临床疗效,为其临床应用提供参考资料。方法:选择189例自2013年6月至2016年6月在我院确诊为单侧输尿管下段结石患者随机分为对照组(n=93)和观察组(n=96),对照组给予肾石通颗粒治疗,观察组给予肾石通颗粒联合盐酸坦洛新缓释胶囊治疗。治疗2周后,观察两组患者的临床有效率、结石排出率、结石排出时间、肾绞痛发生率、肾绞痛视觉模拟量表(VAS)评分及不良反应发生率。结果:观察组临床总有效率为90.62%(87/96),高于对照组的77.42%(72/93);观察组结石排出率为67.79%(67/96),高于对照组的53.76%(50/93);观察组结石排出时间为(7.15±2.67)d,少于对照组的(10.47±3.23)d;观察组肾绞痛发生率为16.67%(16/96),低于对照组32.26%(30/93);观察组VAS评分为(3.15±0.98)分,低于对照组的(4.37±1.25)分,以上比较差异均具有统计学意义(P0.05)。观察组和对照组的不良反应发生率分别为14.58%(14/96)、12.90%(12/93),两组比较差异无统计学意义(P0.05)。结论:在肾石通颗粒基础上加用盐酸坦洛新缓释胶囊可提高输尿管下段结石患者的临床有效率、结石排出率、缩短结石排出时间和减少肾绞痛的发生率。  相似文献   
102.
本文对河南官庄遗址两周时期人牙结石开展了淀粉粒分析,发现了数量丰富的淀粉粒以及少量植硅体。可鉴定形态的淀粉粒主要来自粟、黍、小麦、小豆等农作物以及坚果、块茎植物;植硅体中则有来自水稻颖片的双峰型植硅体。此次研究表明官庄先民食物来源广泛,包括多种农作物和采集植物,其中粟黍类农作物在食物构成中占据主要地位,而小麦所占比例很可能已仅次于粟黍。结合包括官庄遗址和周边若干遗址的浮选结果,两周时期中原腹心地区仍是北方传统的粟作农业,但农作物种植已明显多样化;与此同时,小麦在农作物体系中的重要性增加,中原地区农作物种植体系由以粟黍为主转向以小麦为主的趋势已经出现。  相似文献   
103.
S. aureus and A. baumannii are among the ESKAPE pathogens that are increasingly difficult to treat due to the rise in the number of drug resistant strains. Novel therapeutics targeting these pathogens are much needed. The bacterial enoyl reductase (FabI) is as potentially significant drug target for developing pathogen-specific antibiotics due to the presence of alternate FabI isoforms in many other bacterial species. We report the identification and development of a novel N-carboxy pyrrolidine scaffold targeting FabI in S. aureus and A. baumannii, two pathogens for which FabI essentiality has been established. This scaffold is unrelated to other known antibiotic families, and FabI is not targeted by any currently approved antibiotic. Our data shows that this scaffold displays promising enzyme inhibitory activity against FabI from both S. aureus and A. baumannii, as well as encouraging antibacterial activity in S. aureus. Compounds also display excellent synergy when combined with colistin and tested against A. baumannii. In this combination the MIC of colistin is reduced by 10-fold. Our first generation compound displays promising enzyme inhibition, targets FabI in S. aureus with a favorable selectivity index (ratio of cytotoxicity to MIC), and has excellent synergy with colistin against A. baumannii, including a multidrug resistant strain.  相似文献   
104.
Prediction of predator–prey populations modelled by perturbed ODEs   总被引:1,自引:0,他引:1  
In this paper we explore a stochastic model in continuous time for predator-prey interactions, which accounts for the periodical behaviour observed in many animal populations. More precisely, we consider a solution to the classical Lotka-Volterra system of equations, but we view the actual population sizes as random perturbations of the solutions to this ODE system. Namely, we assume that the perturbations follow correlated Ornstein-Uhlenbeck processes; this approach generalizes the one of Froda and Colavita [Aust N Z J Stat 2:235-254, 2005] who considered only i.i.d. errors. This type of perturbed deterministic model allows to perform parameter estimation and to predict population sizes at future times. On the other hand, the present model refines the previous one since it takes into account the variability due to external factors and the time dependence in the random component. Moreover, this more flexible model improves the predictions of population sizes at future times. In order to illustrate this last point, we analyse two data sets.  相似文献   
105.
Inference on fractal processes using multiresolution approximation   总被引:1,自引:0,他引:1  
We consider Bayesian inference via Markov chain Monte Carlofor a variety of fractal Gaussian processes on the real line.These models have unknown parameters in the covariance matrix,requiring inversion of a new covariance matrix at each Markovchain Monte Carlo iteration. The processes have no suitableindependence properties so this becomes computationally prohibitive.We surmount these difficulties by developing a computationalalgorithm for likelihood evaluation based on a ‘multiresolutionapproximation’ to the original process. The method iscomputationally very efficient and widely applicable, makinglikelihood-based inference feasible for large datasets. A simulationstudy indicates that this approach leads to accurate estimatesfor underlying parameters in fractal models, including fractionalBrownian motion and fractional Gaussian noise, and functionalparameters in the recently introduced multifractional Brownianmotion. We apply the method to a variety of real datasets andillustrate its application to prediction and to model selection.  相似文献   
106.
Coronary obstruction is a life threatening complication during and post-transcatheter aortic valve replacement (TAVR). The objective of this preliminary work is to investigate the mechanisms underlying coronary obstruction in a patient after TAVR, in whom coronary obstruction was confirmed in addition to highlighting the importance of pre-procedural planning. The aortic root of an 80-year old male patient with coronary obstruction during TAVR–where a 29 mm SAPIEN 3 was deployed-was segmented from Computed Tomography scans and 3D-printed with compliant material. Flow and pressure data were acquired in this 3D-printed model in-vitro using a pulse duplicator under physiological conditions for the cases: a 29 mm SAPIEN 3, a 26 mm SAPIEN 3 expanded with a 29 mm balloon, and a 31 mm Medtronic-CoreValve deployed annularly, supra and sub-annularly respectively. Only the CoreValve in sub-annular axial position and the 29 mm SAPIEN 3 yielded pressure gradients (PG) lower than 10 mmHg (6.76 ± 0.52 and 5.72 ± 0.13 mmHg respectively) while the 26 mm SAPIEN 3, CoreValve in normal and supra-annular positions yielded higher PGs (15.5 ± 0.48, 12.2 ± 0.15 and 10.8 ± 0.24 mmHg respectively). 29 mm SAPIEN 3 implantation yielded an FFR value of 45.7 ± 0.6%. However, 31 mm CoreValve in any of the three different annular positions yielded FFR values going from 89.6 ± 1.1% in supra-annular position to 98.3 ± 1.1% in sub-annular position. Implantation with a 26 mm SAPIEN 3 expanded with a 29 mm balloon also yielded an FFR of 92.1 ± 1.2%. Coronary obstruction in this patient could have been prevented through usage of different valve types and/or through usage of a different combination of valve size-balloon sizes.  相似文献   
107.
108.
Coronary artery pressure-drop and distensibility (compliance) are two major, seemingly unrelated, parameters in the cardiovascular clinical setting, which are indicative of coronary arteries patency and atherosclerosis severity. While pressure drop is related to flow, and therefore serves as a functional indicator of a stenosis severity, the arterial distensibility is indicative of the arterial stiffness, and hence the arterial wall composition. In the present study, we hypothesized that local pressure drops are dependent on the arterial distensibility, and hence can provide information on both indices. The clinical significance is that a single measurement of pressure drop could potentially provide both functional and bio-mechanical metrics of lesions, and thus assist in real-time decision making prior to stenting. The goal of the current study was to set the basis for understanding this relationship, and define the accuracy and sensitivity required from the pressure measurement system. The investigation was performed using numerical fluid–structure interaction (FSI) simulations, validated experimentally using our high accuracy differential pressure measurement system. Simplified silicone mock coronary arteries with zero to intermediate size stenoses were used, and various combinations of arterial distensibility, diameter, and flow rate were simulated. Results of hyperemic flow cases were also compared to fractional flow reserve (FFR). The results indicate the potential clinical superiority of a high accuracy pressure drop-based parameter over FFR, by: (i) being more lesion-specific, (ii) the possibility to circumvent the FFR dependency on pharmacologically-induced hyperemia, and, (iii) by providing both functional and biomechanical lesion-specific information.  相似文献   
109.
The goal of this work is to compare coronary hemodynamics as predicted by computational blood flow models derived from two imaging modalities: coronary computed tomography angiography (CCTA) and intravascular ultrasound integrated with angiography (IVUS). Criteria to define boundary conditions are proposed to overcome the dissimilar anatomical definition delivered by both modalities. The strategy to define boundary conditions is novel in the present context, and naturally accounts for the flow redistribution induced by the resistance of coronary vessels. Hyperemic conditions are assumed to assess model predictions under stressed hemodynamic environments similar to those encountered in Fractional Flow Reserve (FFR) calculations. As results, it was found that CCTA models predict larger pressure drops, higher average blood velocity and smaller FFR. Concerning the flow rate at distal locations in the major vessels of interest, it was found that CCTA predicted smaller flow than IVUS, which is a consequence of a larger sensitivity of CCTA models to coronary steal phenomena. Comparisons to in-vivo measurements of FFR are shown.  相似文献   
110.
小河墓地是新疆罗布泊地区一处重要的早期青铜时代墓地。本文主要对该墓地出土颅骨所附牙齿的磨耗程度及牙结石沉积状况进行了观察、量化统计和分析,同时也对该人群其他的口腔疾病如根尖脓肿、颞下颌关节病变、生前牙齿脱落等做了简单的统计,以期从古病理学的角度获取当时居民的口腔健康、食物类型和饮食习惯等信息。本研究发现:1)小河人群的牙齿磨耗程度远远高于对比组的古代居民,其上腭圆枕及颞下颌关节炎出现率较高,存在牙齿崩裂现象,且其前后部牙齿磨耗差异不大。这一方面说明其食物加工技术比较落后,食物粗糙坚硬;另一方面小河居民的经济生活方式和食物构成都比较复杂,不同的食物对前部和后部牙齿磨耗的程度造成了不同的影响;此外,小河人群风沙肆虐的生活环境也对其严重牙齿磨耗的形成产生了一定影响。2)小河人群异常严重的牙结石沉积归功于其高蛋白质和碳水化合物的饮食,以及生活用水的水质。3)统计分析发现两性存在上、下颌犬齿的磨耗差异,而这一情况可能暗示了在家庭手工业方面存在男女分工的现象。  相似文献   
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