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991.
采用恒电位电沉积方法在316L不锈钢表面沉积银纳米镀层, 并将钢板置于全氟硅烷溶液中浸泡, 通过动态凝血实验、 抗凝血时间测定、 血小板黏附实验、 溶血实验和蛋白吸附实验等手段, 测试材料的血液相容性. 结果表明, 通过上述方法可明显改善316L不锈钢的血液相容性, 而抗凝血性能、 溶血率及纤维蛋白吸附量不亚于裸钢板. 与316L裸不锈钢相比, 银镀膜全氟硅烷浸泡316L不锈钢具有良好的血液相容性, 是一种比较理想的冠状动脉支架材料, 具有良好的应用前景.  相似文献   
992.
提出了针对中心血站的管理信息系统的设计方案.通过对各中心血站现有系统的分析,提出了一种基于Web服务的信息管理系统解决方案.介绍了BPM(Business Process Management)的建模方法和MVC设计模式,并在此基础上给出了功能模块设计、业务流程设计在系统研发中的实现技术.运行实践表明该系统简洁实用、性价比高、可扩充性和升级能力好,在实际应用中得到了好评.  相似文献   
993.
Recently published work has reported the development and application of a bottom-up proteomic approach to distinguish between human and animal blood (down to animal species level), by rapid screening using Matrix Assisted Laser Desorption Ionisation Mass Spectrometry (MALDI MS). In that study, it was additionally observed that intravenous animal blood exhibits different spectral profiles from blood collected within the animal chest cavity as well as from the diluted blood collected within packets of meat. In this follow-up study we explored the resulting hypothesis that, depending on how blood is shed or collected, protein biomarker profiles vary to the extent of systematically permitting a distinction between possible sources of blood (for example, flesh wound versus packaged meat). This intelligence may be important in reconstructing the dynamics of the crime. The combination of statistical analysis and tandem mass spectrometry has yielded additional animal blood markers as well as confirming the ability to correctly determine the animal species from which blood derived, regardless of the retailer selling it (amongst the five investigated). These data confirm the initial hypothesis and demonstrate the opportunity for the proteomics-MALDI combined approach to provide additional intelligence to the investigation of violent crimes when examining blood evidence.  相似文献   
994.
Among the many neuroimaging tools available for studying human brain functions, functional magnetic resonance imaging (fMRI) is the most widely used today. One advantage of fMRI over other imaging techniques is its relatively high spatial resolution. High-resolution fMRI, with its superb signal-to-noise ratio and improved tissue-vessel specificity, has strengthened the capability of fMRI and allowed mapping of fine cortical architectures in the human brain. In this review, I will first explain the factors limiting the spatial specificity of the blood oxygenation level-dependent (BOLD) effect, based on which most of fMRI experiments are conducted, and the measures dealing with these factors, and then briefly introduce several high-resolution (sub-millimeter) studies on the functional organization of human primary visual cortex (V1), including mapping of ocular dominance columns, mapping of temporal frequency dependent domains and direct demonstration of tuning to stimulus orientation.  相似文献   
995.
通过文献资料、实验法等对血乳酸在周期性耐力项目中的应用及其与运动能力的关系进行了研究。得出:1)科学训练的目的就是在最大限度上追求一种符合运动项目内在规律的训练方法;2)高、平原值速度的对比,从高原训练下到平原后,阈值对应速度可提高0.2—0.3m/s;3)无氧酵解能力与运动成绩密切相关;4)我省中长跑运动员无氧阈值和我国优秀选手的对比。  相似文献   
996.
将牛、羊红细胞悬浮于等渗生理盐溶液中,消除并隔离与红细胞叠连、聚集有关的生理生化特性,单纯对红细胞沉降率(ESR)进行研究,求出红细胞的Sved-berg常数,同时用高渗、低渗盐溶液悬浮红细胞,利用红细胞的渗透特性,人为改变红细胞的形状、大小,求出异常红细胞Svedberg常数,然后两者进行比较,理论和实验证明:牛红细胞的正常Svedberg常数为7.78×10—8S,与红细胞的大小,形状和可变度有关,具有一定的临床意义,由于绵羊红细胞脆性较大,无法求出Svedberg常数。  相似文献   
997.
A new anhydro disaccharide monomer, 1,6‐anhydro‐2,3‐di‐o‐benzyl‐4‐o‐(2′,3′,4′,6′‐tetra‐o‐benzyl‐β‐D ‐galactopyranosyl)‐β‐D ‐glucopyranose (benzylated 1,6‐anhydro lactose (LSHBE)), was synthesized from D ‐lactose to investigate the polymerizability and biological activities of the resulting branched polysaccharides. The ring‐opening polymerization of LSHBE was carried out with phosphorus pentafluoride as a catalyst under high vacuum to give a stereoregular benzylated (1 → 6)‐α‐D ‐lactopyranan. The molecular weights of poly(LSHBE)s increased with an increase in the amount of CH2Cl2 solvent, and polymerization temperatures were affected in both molecular weights and yields of the polymers. The copolymerization of LSHBE with benzylated 1,6‐anhydro‐β‐D ‐glucopyranose (LGTBE) gave the corresponding copolysacchrides having different proportions of lactose and glucose units in good yields. After debenzylation to recover hydroxyl groups and then sulfation, sulfated homopoly(lactose)s and copoly(lactose and glucose)s were obtained. Sulfated homopoly(lactose)s had moderate anti‐HIV (EC50 = 5.9 and 1.3 μg/mL) and blood anticoagulant activities (AA = 18 and 13 unit/mg), respectively. Sulfated copoly(lactose and glucose) having 15 mol % lactose units gave high anti‐HIV and blood anticoagulant activities of 0.3 μg/mL and 54 unit/mg, respectively. These biological results suggest that the distance between branched units on the main chain plays an important role in the anti‐HIV and blood anticoagulant activities. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 913–924, 2009  相似文献   
998.
Cardiovascular disease is one of the leading causes of morbidity and mortality in the western hemisphere. Currently available synthetic vascular conduits, like Dacron or ePTFE show excellent long‐term results for large‐caliber arterial reconstruction (aorta, iliac vessels) but when used for small diameter (<4 mm) vessel reconstruction, patency rates are extremely poor. We therefore aim at developing suitable blood vessel substitutes out of biocompatible photopolymer formulations, which can be printed by rapid prototyping. Rapid prototyping offers the possibility to create cellular structures within the grafts that favor the ingrowth of tissue. To meet the high requirements for artificial biomaterials, it is necessary to develop new resin formulations. Beside the biocompatibility, the mechanical properties—a low elastic modulus (500 kPa) at a relatively high tensile strength (1.0 MPa) and a high strain at break (130%)—play a central role. Resin systems containing cyanoethyl acrylate have shown to be highly reactive, have good mechanical properties and sufficient in vitro biocompatibility. Elastic modulus and tensile strength which should be similar to natural blood vessels were adjusted by the ratio of acrylate‐based crosslinkers and—in case of hydrogels —the percentage of water. Finally, we were able to print small diameter conduits by microstereolithography. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2664–2676, 2009  相似文献   
999.
本文通过对18例头痛病例的分析,找出其病因,进行初步探讨,说明头痛的病因是多方面的,有时可成为某些严重疾病的一个危险信号.  相似文献   
1000.
从HABT陶瓷的电性能测试及对定向基片上细胞生长率的观察,确认它具有合适的压电性能诱导骨细胞生长.生物学性能检测表明HABT陶瓷无毒,适合于作生物种植材料.  相似文献   
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