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目的:正交试验优选猫爪草纳米乳喷雾剂的最佳提取工艺。方法:以总黄酮提取量和浸膏得率的综合评分为评价指标,在单因素试验基础上,采用L9(34)正交试验考察猫爪草醇提工艺的溶剂体积、乙醇浓度、提取时间及提取温度对提取工艺的影响。结果:最佳提取工艺为以75%乙醇为提取溶剂,提取温度60℃,第1次8倍量1.5 h,第2次7倍量1 h,共提取2次。结论:在单因素试验基础上,通过正交试验优选的提取工艺经验证稳定、简便易行、预测性好,为猫爪草纳米乳喷雾剂的进一步研发奠定了基础。  相似文献   
3.
几种有效消毒方法对藻酸盐印模精度的影响   总被引:2,自引:0,他引:2  
目的:比较几种有效的消毒方法对藻酸盐印模精度的影响,以寻求适合临床的消毒方法。方法:制作一个标准下颌牙列金属母模。采用3种有效的消毒方法(1500mg/L的NaClO消毒液浸泡消毒,1500mg/L的NaClO消毒液喷涂消毒及2%戊二醛消毒液浸泡消毒),分别按起效作用时间、起效作用时间延长10min和延长20min共分为9个实验组,每组均制备10个藻酸盐印模进行消毒处理后灌制模型,另外制取10个未消毒的藻酸盐印模作为对照组,用测量显微镜测量模型各标志点的距离,所得数据进行统计分析。结果:①1500mg/L的NaClO消毒液浸泡消毒10~30min对印模精度无明显影响。②1500mg/L的NaClO消毒液喷涂消毒藻酸盐印模45min时,出现统计意义显著的形变(P〈0.05)。③2%戊二醛消毒液浸泡处理50min、60min时,印模出现统计学意义显著的形变(P〈0.05)。结论:不影响藻酸盐印模精度的消毒方法为:1500mg/L的NaClO消毒液浸泡消毒10~30min,1500mg/L的NaClO消毒液喷涂消毒25~35min,2%戊二醛消毒液浸泡处理40min。  相似文献   
4.
Background: A new microplasma spraying equipment (MSE) to deposit calcium phosphate (CaP) ceramic coatings onto titanium substrates has been developed. With this system, it is possible to spray fine particles and to apply textured hydroxylapatite coatings onto titanium surfaces. Moreover, due to the low heat power of the microplasma jet, overheating of the powder particles as well as excessive local overheating of the substrate are diminished. Furthermore, because of the small laminar plasma jet, it is possible to achieve high spray efficiency in the case of spraying for dental implants. Also, the low level of noise (25–50 dB) and hardly any dust makes it possible to operate MSE under conditions of normal workrooms. Objective: The aim was to investigate, in a mandibular dog model, the effect of functional load on soft‐tissue adaptation as well as crestal bone‐level changes around titanium implants provided with newly developed microplasma‐sprayed CaP coatings. Material and methods: For histomorphometrical evaluation, 56 screw‐type titanium implants were inserted into the mandibles of seven adult Beagle dogs. The implants were either acid etched without an additional coating, coated with a conventionally plasma‐sprayed CaP ceramic (PS), coated with a microplasma‐sprayed CaP ceramic (MPS) or with a microplasma‐sprayed coating at only the apical part (aMPS). To assess the effect of occlusal loading, a split‐mouth design was used. Six weeks after implantation, the implants in one half of the mandible of each dog were functionally loaded whereas the contra lateral implants served as control. One year after loading, the animals were sacrificed. Soft‐tissue dimension as well as marginal bone level were histologically assessed. Results: Histometric analysis of undecalcified histologic sections included the evaluation of the sulcus depth, the dimension of the junctional epithelium and the connective tissue as well as the first bone‐to‐implant contact. For MPS‐surfaced implants, functional loading was associated with – compared with the non‐loaded state – unchanged soft‐tissue dimension. Furthermore, the soft‐tissue dimension did not differ from the dimensions around non‐coated, PS and aMPS implants. Moreover, the first bone‐to‐implant contact was not significantly altered by functional loading and comparable non‐coated, PS and aMPS implants. Conclusion: Within the limits of the experiment, we conclude that, in comparison, functional loading does not affect the marginal soft‐tissue response to MPS CaP‐coated implants. However, in comparison, functional loading might affect marginal bone response to MPS CaP‐coated implants. To cite this article:
Junker R, Manders PJD, Wolke J, Borisov Y, Braceras I, Jansen JA. Bone reaction adjacent to microplasma‐sprayed calcium phosphate‐coated oral implants subjected to occlusal load, an experimental study in the dog. Clin. Oral Impl. Res. 22 , 2011; 135–142.
doi: 10.1111/j.1600‐0501.2010.02025.x  相似文献   
5.
针对人工滴染血涂片出现的染色不均匀、效率较低等问题,提出一种基于压力旋流雾化喷头对血涂片进行喷染的方法。采用数值模拟与实验相结合的方法对瑞氏-姬姆萨染液雾化过程进行分析,并探索最佳喷染参数。首先利用ANSYS软件仿真计算染液在喷头内部的流动状态,然后使用相机和喷雾激光粒度仪搭建喷头外部雾化场实验平台,喷头外部入口压力分别选取0.10、0.12、0.14、0.16、0.18、0.20、0.22、0.24 MPa,测量染液的雾化角以及喷头正下方10~50 mm的雾化区域内测量点的雾滴粒径参数(Dv10,Dv90和雾滴体积中径Dv50),计算粒度分布跨度S,并在此基础上开展血涂片喷染研究,并对比了人工滴染和喷染后的细胞图像背景灰度参数。仿真结果表明:染液在压力旋流雾化喷头出口处形成高速液膜,为形成雾化场提供理论依据。实验结果表明:当喷头入口压力为0.20 MPa时,距离喷头正下方35 mm处喷染界面具备最优的雾化质量,此时喷头雾化角为76.13°,雾滴体积中径为75 μm,雾滴粒度分布跨度为1.72。基于该参数条件进行喷染后的细胞图像背景灰度参数与滴染相比存在显著性差异(P<0.01),喷染后的细胞图像背景灰度显著降低。研究结果表明,压力旋流雾化喷头可以应用于血涂片染色,并且喷染后的血涂片染色均匀,具备良好的染色效果,为血涂片染色提供了新的方案。  相似文献   
6.
The use of sublingual nitroglycerin spray has been studied in twenty patients referred to our Intensive Care Unit for further treatment of severe left ventricular failure. Within five minutes of spray administration significant falls in pulmonary artery occlusion pressure, mean arterial pressure, heart rate, right atrial pressure and systemic vascular resistance occurred. Similarly significant increases in cardiac index, stroke volume index and left ventricular stroke work index were found. These results show a considerable improvement in the haemodynamic parameters of invasively monitored patients and we believe that its administration undoubtedly buys time for the critically ill patient. However, we would caution against its routine use at present in view of the potential problem of hypotension, until further information is available.  相似文献   
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目的:探讨超高龄气管切开患者脱机期间雾化吸入的最佳方案。方法选择我科60例超高龄气管切开患者,脱机期间分为两组,试验组采用婴儿面罩雾化器,调氧流量6~8L/min,取面罩盖于气切口,调绑带松紧度并固定于患者颈部给予雾化吸入;对照组采用口含式雾化器。调氧流量6~8L/min给予雾化吸入。结果试验组用婴儿面罩雾化,湿化效果明显优于直接将雾化器连接在气管切开处,雾化不良反应明显减少,未发生药液倾倒。同时减轻护理工作量,提高患者满意度,差异有统计学意义(P<0.05)。结论应用婴儿面罩进行雾化治疗,能充分发挥湿化效果,减少患者对冷雾化气体的刺激反应,效果满意,值得推广。  相似文献   
9.
The aim of this is to review deaths associated with the use of Riot Control Agents (RCAs) and to assess how the presenting pathologies is such cases may better inform cause of death conclusions upon autopsy. We also sought to present which additional steps should be added to the Minnesota protocol and the European harmonization of medico-legal autopsy rules in suspected cases of deaths associated with the use of RCAs.We included 10 lethal cases in our study. In three cases, RCAs were found to be the sole cause of death, in three cases RCAs were ruled a secondary cause of death due asphyxia or asthma subsequent to exposure to RCAs and in four cases RCAs were contributory factors to death. In three cases the responsible agents were identified as Chloroacetophenone (CN), Chlorobenzylidene malononitrile (CS) and Oleoresin capsicum (OC) and in the remaining 7 cases, the agent was OC alone.As there are no specific findings in suspected cases of death associated with RCA use, establishing cause of death and whether RCAs are the sole cause or only a contributory factor will be based on the elimination of other possible causes of death. For this reason, a specifically structured autopsy is essential. This specifically structured autopsy should contain basic principles of the Minnesota Protocol and the European harmonization of medico-legal autopsy rules with the following additional steps taken: examination of clothing, eyes, and skin; examination of pharyngeal, tracheobronchial, and eusophegeal mucosas; and a thorough recording of the steps taken by the party conducting the arrest, including other possible causes of in-custody death, as well as a detailed medical history of the deceased.  相似文献   
10.
目的探讨胃镜下去甲肾上腺素药物喷洒与肾上腺素注射治疗非静脉曲张性上消化道大出血的疗效。方法 160例符合纳入标准的非静脉曲张性上消化道大出血患者按治疗方案分为药物喷洒组(80例)和药物注射组(80例)。所有患者均给予上消化道大出血的常规治疗。药物喷洒组患者在胃镜下给予去甲肾上腺素喷洒治疗,而药物注射组在胃镜下给予肾上腺素注射治疗。观察两组患者治疗疗效、止血时间、再出血率及不良反应发生情况。结果药物注射组的治疗总有效率为95.0%,明显高于药物喷洒组的80.0%(P0.05)。与药物喷洒组相比,药物注射组的止血时间明显缩短,再出血率明显降低(均P0.05)。治疗过程中,两组均未发生严重不良反应,其不良反应发生率在两组间比较差异无统计学意义(P0.05)。结论胃镜下肾上腺素注射是非静脉曲张性上消化道大出血的有效治疗方案,可以提高治疗有效率,缩短止血时间,且不良反应轻,疗效优于去甲肾上腺素喷洒治疗,临床上值得进一步研究。  相似文献   
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