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排序方式: 共有1729条查询结果,搜索用时 31 毫秒
31.
Christian A. Skrabal Amir Khosravi Bernd Westphal Gustav Steinhoff 《Scandinavian cardiovascular journal : SCJ》2013,47(4):224-229
Objectives. In this study, the immuno- and neuroprotective effect of a novel cardiopulmonary bypass coating was investigated. Design. Thirty nine patients scheduled for elective coronary artery bypass grafting were randomly assigned to either PMEA-coated (n?=?19) or non-coated CPB circuits (n?=?20). Pericardial suction blood was separated and retransfused only if needed at the end of operation. Neurocognitive functions were examined preoperatively and 7–10 days postoperatively using a standard neuropsychological test battery. Assuming an inflammatory etiology, the most cogent inflammatory markers were perioperatively analyzed. Results. Postoperatively, patients of the PMEA-coated group performed better in Go/NoGo and Mini-Mental-test than patients of the non-coated group (p?<?0.04). Other neurocognitive testing did not reveal significant differences between the groups. Although most inflammatory parameters showed a significant intraindividual increase during or shortly after CPB, there was no difference in inflammatory alteration between the groups. Conclusions. PMEA-coating of cardiopulmonary bypass surfaces revealed some minor benefits in preservation of neurocognitive functions after surgery. The immediate inflammatory response remained mostly unaffected. Suction blood separation may additionally contribute to proper postoperative outcome. 相似文献
32.
S. A. Agnihotri 《Journal of microencapsulation》2013,30(7):709-718
Controlled release formulations of clozapine microparticulated tablets were prepared by using chitosan. Microparticles were characterized for particle size and size distribution. Microparticles were compressed into tablets using the directly compressible excipients. SEM photographs of the fractured part of the tablet revealed the presence of discrete particles in the tablets, suggesting that the system chosen is ideal for tableting. Drug release from the tableted microparticles exhibited an initial burst effect, but the release decreased with increasing extent of cross-linking. Tablets were coated with chitosan or cellulose acetate, which significantly lowered the initial burst effect when compared to uncoated tablets. Drug release from chitosan-coated tablets was slightly higher than the tablets coated with cellulose acetate. Tablets prepared were effective in delivering clozapine over a period of 12?h. 相似文献
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���������� ���������������Ƹ� 《中国实用口腔科杂志》2016,9(1):49-53
??Oral implant-related infection has already become an important factor affecting implant osseointegration so far. In order to decrease the incidence of infection??implant surface modification coating with antibacterial properties has been researched intensely in recent years. In this paper??classification of different implant surface antimicrobial coating and research status both in the antibacterial mechanism and clinical applications of various types were reviewed. 相似文献
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ObjectiveDental plaque is a causative factor for oral disease and a potential reservoir for respiratory infection in the elderly. Therefore, there is a critical need for the development of effective methods to remove oral biofilm. The objective of this study was to investigate the effect of proteases on oral biofilm formation andremoval.DesignThe in vivo effect of actinidin, a cysteine protease, on the removal of tongue coating was assessed after orally taking a protease tablet. Effects of the proteases trypsin, papain and actinidin on Actinomyces monospecies biofilm and multispecies biofilm that was reconstructed using a plaque sample from the tongue coating were investigated using the microtiter plate method. Antimicrobial tests and limited proteolysis of fimbrial shaft proteins were also performed to clarify underlying mechanisms of oral biofilm removal.ResultsTablets containing actinidin removed tongue coating in elderly subjects. Oral Actinomyces biofilm was significantly reduced by the proteases papain, actinidin and trypsin. Papain and trypsin effectively digested the major fimbrial proteins, FimP and FimA, from Actinomyces. Actinidin, papain and trypsin reduced multispecies biofilm that was reconstructed in vitro. Papain and trypsin inhibited formation of multispecies biofilm in vitro.ConclusionsThis study shows that proteases reduced oral biofilm in vivo in elderly subjects and in vitro, and suggests that protease digests fimbriae and inhibits biofilm formation. 相似文献
36.
Di Mario Carlo Sansa Mara Airoldi Flavio Sheiban Imad Manari Antonio Petronio Anna 《Acute cardiac care》2013,15(3-4):128-133
DESIGN: Prospective randomized, multicentre study. RATIONALE: Recanalisation of the culprit lesion is the main goal of primary angioplasty for acute myocardial infarction. With the exception of cardiogenic shock, staged procedures are performed in the presence of multivessel disease. The study hypothesis is that with modern non-thrombogenic stents (heparin coated) complete revascularization with multivessel treatment can be safely achieved during the primary angioplasty procedure with a lower need of subsequent revascularization procedures and at a lower cost. ENDPOINTS: PRIMARY: 12-month incidence of repeat revascularization (any revascularization, infarct related artery as well as non-infarct-related artery). SECONDARY: (1) in hospital repeat revascularization, reinfarction and death; (2) total hospital cost (including a 12 months follow-up period). METHODS: 69 patients with ST elevation Acute Myocardial Infarction (AMI), <12 hours after symptoms onset, undergoing primary angioplasty, with documented multivessel disease and both culprit lesion and 1 to 3 other lesions suitable for stent implantation. Unbalanced randomization between culprit lesion treatment only ( n??=?17) and complete multivessel treatment (n?=?52, with 71 additional lesions treated).RESULTS: The two groups were well balanced in terms of clinical characteristics, number of diseased vessels and angiographic characteristics of the culprit lesion. In the complete multivessel treatment group 2.36?±?0.64 lesions per patient were treated using 2.73?±?0.78 heparin coated stents (1.00 lesions and 1.29?±?0.61 stents in the culprit treatment group, bothp?<?0.001). The duration of the procedure increased from 53?±?21?min (culprit treatment group) to 69?±?32?min (p?=?0.032) and the amount of contrast used from 242?±?102?ml (culprit treatment group) to 341?± 163?ml (multivessel complete treatment),p?=?0.025. A similar low incidence of in-hospital major adverse cardiac events was observed in the 2 groups (0 and 3.8% in culprit and multivessel treatment groups,p?=?0.164). The increase in the incidence of new revascularisation in the culprit treatment group at 12 month follow-up was not significant (35 vs 17%,p?=?0.247) but was sufficient to compensate the initial higher in-hospital cost, with a similar 12 month hospital cost in the 2 groups (€22 330?±?€13 653 vs €20 382?±?€11 671,p?=?0.231).CONCLUSION: Multivessel treatment during primary PTCA was safe in this controlled trial. However, when only the culprit lesion was initially treated, the need for subsequent clinically driven revascularization remained low and no clinical or economical advantages were obtainable with a more aggressive initial approach. In clinical practice, a staged approach to multivessel treatment during primary angioplasty avoids to treat unnecessarily non clinically relevant lesions. (Int J Cardiovasc Intervent 2004; 6: 128-133) 相似文献
37.
Subwavelength Etched Colloidal Monolayers: A Model System for Tunable Antireflective Coatings 下载免费PDF全文
Christian Stelling Christoph Bernhardt Markus Retsch 《Macromolecular chemistry and physics.》2015,216(16):1682-1688
Colloidal monolayers represent a versatile material class to fabricate nanostructures with high quality. The length scale of the nanostructured film is given by the size of the colloidal nanoparticles. Importantly, colloidal monolayers, though being of hexagonally close packed symmetry, still embody a high amount of free volume. This reduces the effective refractive index of thin colloidal monolayer films significantly. For particles and periodicities <200 nm, the heterogeneous layer can be approximated by an effective medium theory. The amount of free volume can be further fine‐tuned by a controlled size reduction of the constituting spheres, for instance by plasma etching. This can be utilized to realize an optimum refractive index for the application of colloidal monolayers as antireflective (AR) coatings. In contrast, previously reported >200 nm monolayers demonstrate distinct extinction peaks due to grating diffraction. Rational design by the use of differently sized particles further allows shifting the best performance across the visible spectrum. Colloidal monolayers, though representing single‐layer AR coatings, exhibit broadband AR properties and are ideally suited to demonstrate the influence of refractive index and layer thickness, independently.
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39.
目的:了解学龄前儿童口腔中挥发性硫化物的检出情况,分析引起学龄前儿童口臭的主要相关因素,为儿童口臭和相关疾病的预防和治疗提供依据. 方法:对北京市某幼儿园170名4~6岁学龄前儿童口腔中挥发性硫化物( volatile sulfur compounds,VSC)含量和口腔健康状况进行检查,对儿童家长进行问卷调查,挥发性硫化物的检测使用便携式气相色谱仪OralChromaTM. 使用SPSS 13. 0软件包,进行VSC与口腔健康状况和行为等的单因素和多因素分析. 结果:单因素分析结果显示,检出口臭的儿童占全部受检人数的34. 4%. 女童口腔中硫化氢( hydro-gen sulfide,H2S)[(1.59 ±2.41) ng/10 mL]和VSC总量[(2.14 ±4.42) ng/10 mL]高于男童(P<0.05). 舌苔指数高的儿童的H2S[舌苔面积(1.68 ±2.48) ng/10 mL,舌苔厚度(2.18 ±2.69) ng/10 mL)和VSC总量[舌苔面积(2. 26 ± 4. 31) ng/10 mL,舌苔厚度(2. 41 ± 3. 02) ng/10 mL]高于舌苔指数低的儿童(P<0. 01). 简化软垢指数记分值≥2的位点数值与甲硫醇(methyl mercaptan,CH3SH)和二甲基硫[dimethyl sulfide,(CH3)2S]浓度呈正相关(P<0.01);母亲受教育程度在本科及以上的儿童口腔中H2S值[(1.19 ±1.62)ng/10 mL]显著低于母亲教育程度在本科以下的儿童(P<0. 01);甜食进食频率高的儿童H2S浓度[(1. 04 ± 1. 55) ng/10 mL]低于频率低的儿童(P<0. 01);有张口呼吸习惯的儿童CH3SH和(CH3)2S浓度[(0. 29 ± 1. 92) ng/10 mL,(0. 37 ± 2. 06) ng/10 mL]显著高于没有张口呼吸习惯的儿童(P<0. 05). Logistic多因素分析结果显示,舌苔指数高、母亲教育程度低的儿童VSC高于舌苔指数低和母亲教育程度高的儿童. 结论:学龄前儿童口臭检出率高,性别、舌苔指数、软垢指数、母亲教育程度、甜食进食频率、张口呼吸等因素是儿童口臭的相关影响因素,不同影响因素导致不同VSC成分的改变. 相似文献
40.
The aim of the investigation was to develop the use of topographic and nano-adhesion atomic force microscopy(AFM) studies as a means of monitoring the coalescence of latex particles within films produced from a pharmaceutically relevant aqueous dispersion(Eudragit~?NE30 D). Films were prepared via spin coating and analysed using AFM, initially via tapping mode for topographic assessment followed by force-distance measurements which allowed assessment of site-specific adhesion. The results showed that colloidal particles were clearly observed topographically in freshly prepared samples, with coalescence detected on curing via the disappearance of discernible surface features and a decrease in roughness indices. The effects of temperature and humidity on film curing were also studied, with the former having the most pronounced effect. AFM force measurements showed that the variation in adhesive force reduced with increasing curing time, suggesting a novel method of quantifying the rate of film formation upon curing. It was concluded that the AFM methods outlined in this study may be used as a means of qualitatively and quantitatively monitoring the curing of pharmaceutical films as a function of time and other variables, thereby facilitating rational design of curing protocols. 相似文献