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291.
目的:探索介入治疗下肢动脉硬化闭塞症(ASO)的临床疗效及其影响因素。方法:选择2012年10月至2013年8月我院收治的ASO患者96例,按照治疗方法将所有患者平均分成对照组和实验组,每组48例。对照组进行常规药物治疗,实验组在常规药物治疗基础上行介入手术。考察患者临床疗效及踝肱指数(ABI),并应用二元Logistic回归研究影响ASO复发的因素。结果:术后1个月、3个月、6个月、1年,随着时间的延长,ABI值呈下降趋势,且实验组患者的ABI值在各时间点均明显高于对照组,差异具有统计学意义(P0.05)。其中对照组患者有效率为31.25%,实验组患者有效率为87.50%,实验组有效率显著高于对照组,差异具有统计学意义(P0.05)。糖尿病和高胆固醇症可以单独影响ASO复发。结论:介入治疗ASO患者具有良好的疗效,显著提高患者的ABI,但术后需严格控制血糖和血脂。 相似文献
292.
Carlos Martínez‐Pérez Pablo Plasencia David Jones Tea Kolar‐Jurkovšek Jingeng Sha Hector Botella Philip C.J. Donoghue 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2014,47(4):547-555
Knowledge of conodont element function is based largely on analysis of morphologically similar P1 elements of few comparatively closely related species known from abundant articulated remains. From these, a stereotypical pattern of rotational occlusion has been inferred, leading to the suggestion that this may represent a general model for ozarkodinin P1 elements at the very least. We test the generality of this occlusal model through functional analysis of Pseudofurnishius murcianus P1 elements which, though superficially similar to homologous elements in gnathodids, evolved their platform morphology independently, through a different mode of morphogenesis, and in a different topological position within the element. Our integrated functional analysis of several articulated clusters of P1 elements encompassed physical and virtual occlusal analyses, constrained by microwear and sharpness analyses. All of the evidence supports an occlusal model in which the Pseudofurnishius P1 elements occluded with the dextral blade located between the rostral face of the sinistral blade and the first cusp of the rostral primary process. In achieving this, the dorsal and ventral blades guided the opposing elements, and the rostral processes of both elements guided the final stages of precise occlusion. Spalling and microwear on the non‐occlusal side of the element evidence malocclusion, requiring the complete separation of elements within the occlusal cycle. This occlusal cycle is entirely linear, orthogonal to the plane of attachment of the elements. Evidently, the rotational occlusal model is not general for P1 elements, even for ozarkodinins, and it is likely that among conodonts occlusal kinematics are as disparate as element morphologies. Attempts to elucidate the diversity of occlusal kinematics and, therefore, feeding ecologies of conodonts will be repaid by an understanding of the role of this important abundant and diverse clade in Palaeozoic and Mesozoic marine ecosystems. 相似文献
293.
Hari Hara Sudhan Lakshmanan Joseph J. Shatzel Sven R. Olson Owen J.T. McCarty 《Computer methods in biomechanics and biomedical engineering》2019,22(11):972-980
Vascular geometry is a major determinant of the hemodynamics that promote or prevent unnecessary vessel occlusion from thrombus formation. Bifurcations in the vascular geometry are repeating structures that introduce flow separation between parent and daughter vessels. We modelled the blood flow and shear rate in a bifurcation during thrombus formation and show that blood vessel bifurcation ratios determine the maximum shear rate on the surface of a growing thrombus. We built an analytical model that may aid in predicting microvascular bifurcation ratios that are prone to occlusive thrombus formation. We also observed that bifurcation ratios that adhere to Murray’s law of bifurcations may be protected from occlusive thrombus formation. These results may be useful in the rational design of diagnostic microfluidic devices and microfluidic blood oxygenators. 相似文献
294.
Enes Elvin Gul Reda Abuelatta Sohaib Haseeb Mohammad Melhem Osama Al Amoudi 《Indian pacing and electrophysiology journal》2019,19(1):27-29
Venous revascularization is an approach used in patients with total venous occlusion requiring venous access for cardiac device lead placement. Several percutaneous approaches to venous revascularization have been proposed. For the first time, we describe the case of a 69-year-old male with total venous occlusion who was successfully revascularized using a ‘diathermy’ technique. 相似文献
295.
Jian Liu Yan Li Yao Yu Xincheng Yuan Hongyu Lv Lanxiang Liu Yuqian Zhao Yi Wang Zhenhe Ma 《Journal of biophotonics》2020,13(2)
The progression of ischemic cerebral edema (CE) is closely related to the level of cerebral blood perfusion (CBP) and affects each other. Simultaneous detection of CBP and CE is helpful in understanding the mechanisms of ischemic CE development. In this article, a wide field of view swept‐source optical coherence tomography system was used to detect CE status and CBP levels simultaneously in middle cerebral artery occlusion rats. Images reflecting these two physiological states can be reconstructed with only one C‐scan. We quantify these two physiological states into four parameters, which contain two vascular parameters (vascular displacement distance and vascular perfusion density) and two edema parameters (optical attenuation coefficient and edema area). The association between the two vascular parameters and the two edema parameters was analyzed. The results show that there is a strong linear relationship between blood flow parameters and edema parameters. This work provides a new option for CE in vivo detection, and is very likely to play an important role in the development of relevant drugs or in selection of treatment options. 相似文献
296.
《Saudi Journal of Biological Sciences》2020,27(1):500-517
ObjectiveHere, the aim is to improve the bioavailability of Naringenin (NRG) in brain and to establish the highest remedial benefit from a novel anti-ischemic medicine i.e. NRG.MethodsA novel Naringenin-loaded-nanoemulsion (NE)-(in situ)-gel (i.e. thermoresponsive), was formulated with the help of Poloxamer-407 (20.0% w/v). Chitosan (CS, 0.50% w/v) was used to introduce the mucoadhesive property of NE-(in situ)-gel and finally called as NRG-NE-gel + 0.50%CS. A novel UHPLC-ESI-Q-TOF-MS/MS-method was optimized and used for NRG-NE-gel + 0.50%CS to quantify the Pharmacokinetic-(PK)-parameters in plasma as well as brain and to evaluate the cerebral ischemic parameters after MCAO i.e. locomotor activity, grip strength, antioxidant activity, and quantity the infarction volume in neurons with the safety/toxicity of NRG-NE-gel + 0.50%CS after i.n. administration in the rats.ResultsThe mucoadhesive potency and gelling temperature of NRG-NE-gel + 0.50%CS were observed 6245.38 dynes/cm2 and 28.3 ± 1.0 °C, respectively. Poloxamer-407 based free micelles size was observed 98.31 ± 1.17 nm with PDI (0.386 ± 0.021). The pH and viscosity of NRG-NE-gel + 0.50%CS were found to be 6.0 ± 0.20 and 2447 ± 24cp (at 35.0 ± 1.0 °C temperature), respectively. An elution time and m/z NRG were observed 1.78 min and 270.97/150.96 with 1.22 min and m/z of 301.01/150.98 for Quercetin (IS) respectively. Inter and intra %precision and %accuracy was validated 1.01–3.37% and 95.10–99.30% with a linear dynamic range (1.00 to 2000.00 ng/ml). AUC0-24 of plasma & brain were observed 995.60 ± 24.59 and 5600.99 ± 144.92 (ng min/ml g) in the rats after the intranasal (i.n.) administration of NRG-NE-gel + 0.50%CS. No toxicological response were not found in terms of mortalities, any-change morphologically i.e. in the microstructure of brain as well as nasal mucosa tissues, and also not found any visual signs in terms of inflammatory or necrosis.ConclusionIntranasally administered NRG-NE-gel + 0.50%CS enhanced the bioavailability of Naringenin in the brain. In the cerebral ischemic rats, significantly improved the neurobehavioral activity (locomotor & grip strength) followed by antioxidant activity as well as infarction volume. Finally, the toxicity studies carried out and established the safe nature of optimized-NRG-NE-gel + 0.50%CS. 相似文献