不同口腔冲洗液对经口气管插管机械通气患者口腔感染和呼吸机相关性肺炎的影响

目的探讨经口气管插管患者采用不同口腔冲洗液对口腔环境及呼吸机相关性肺炎(VAP)的影响。方法按冲洗液的不同将93例经口气管插管机械通气患者分为两组,A组47例予1%双氧水(H_2O_2)溶液+2.5%碳酸氢钠(NaHCO_3)溶液+生理盐水负压冲洗口腔,B组46例予2.5%NaHCO_3溶液+生理盐水负压冲洗,观察比较两组患者口腔感染及VAP发生情况。结果干预1、3、5天时,A组口腔异味程度和干预后牙菌斑评分明显低于B组,干预后口腔感染、溃疡以及VAP发生率也明显低于B组,差异均有统计学意义(均P0.05)。结论经口气管插管机械通气患者采用1%H2O2溶液、2.5%NaHCO3溶液和生理盐水冲洗液组合负压冲洗口腔,可有效改善患者口腔环境,减少感染与VAP的发生。     

0.1％西吡氯铵含漱液对牙外伤纤维夹板固定术后菌斑形成的抑制作用

目的 观察0.1％西吡氯铵含漱液对牙外伤纤维夹板固定术后菌斑形成的抑制作用.方法 牙外伤患者40例随机分为2组,应用双盲法分别给予患者0.1％西吡氯铵含漱液漱口(试验组)或0.12％氯己定含漱液漱口(对照组).每天5次,分别在晨起、睡前、三顿饭后各漱口1次,每次含15 mL,持续漱口60 s,漱口后1h内禁饮食,7d为一疗程.就诊当天(1 d)、4d和8d,按照Quigley-Hein指数(Turesky改良)测定菌斑指数.结果 中期检查试验组和对照组菌斑指数组间比较差异无统计学意义(P＞0.05);终点检查试验组和对照组菌斑指数组间比较差异无统计学意义(P＞0.05).结论 0.1％西吡氯铵含漱液可抑制牙外伤纤维夹板固定术后菌斑的形成,有利于牙周损伤的愈合.     

立体型经口气管固定法对ICU患者非计划性拔管的影响

目的探讨改良方法立体型经口气管固定法固定经口气管插管的安全性和舒适性。方法将我院2014年1月~2015年12月收治的489例经口气管插管意识清醒患者进行分组,其中对照组237例采用传统方法固定经口气管插管,实验组252例采用立体型经口气管固定法固定经口气管插管,观察比较两组非计划性拔管发生率、气管导管的牢固度以及并发症发生情况。结果实验组非计划性拔管发生率、气管导管的牢固度均优于对照组(P0.05);并发症发生率低于对照组,且口腔护理效果优于对照组,组间比较差异有统计学意义(P0.05)。结论立体型经口气管固定法能有效降低非计划性拔管发生率,固定气管导管更牢固,并发症的发生率明显降低,且方便口腔护理,具有一定的临床应用价值。     

个体化口腔护理在预防呼吸机相关性肺炎中的应用研究

目的应用循证护理理论探讨ICU经口气管插管患者口腔护理中存在的问题,提高患者口腔护理质量,降低和预防呼吸机相关性肺炎(VAP)发生率。方法将2012年1月~2013年5月入住我科符合入选标准的经口气管插管患者60例,按入院时间先后随机分为对照组和观察组各30例。对照组采用传统口腔护理方法;观察组实行层级护理,每天由护理组长根据患者的口腔情况选择适宜口腔护理液和个体化的口腔护理方法,开出护嘱,指导责任护士进行口腔冲洗和口腔擦拭。结果观察组口臭、口腔炎、真菌感染及VAP发生率明显低于对照组(P0.05),差异具有统计学意义。结论冲洗和擦洗结合的个体化口腔护理效果优于常规的口腔护理方法,能够有效预防和减少呼吸机相关性肺炎的发生。     

气囊管理联合个体化口腔护理在预防呼吸机相关性肺炎中的研究

目的探讨气管插管气囊管理联合个体化口腔护理对预防经口气管插管机械通气患者呼吸机相关性肺炎(VAP)的效果,为临床选择合适的口腔护理方法提供依据。方法选择2014年1月~2015年12月收住我科符合入选标准的经口气管插管患者97例,按入院先后顺序随机分为对照组30例,观察A组34例,观察B组33例。对照组采用常规擦拭法行口腔护理;观察A组根据病人的口腔情况选择适宜的口腔护理液及个体化的口腔护理方法;观察B组在观察A组的基础上,在进行口腔护理之前,将患者头颈部处于舒展体位,用气囊压力表监测气囊压力,将气囊压力调整至30~35cmH2O,待口腔护理结束后调整压力为25~30cmH2O。结果对照组与观察A、B组患者的口腔清洁率和口腔并发症发生率比较,差异有统计学意义(P0.05);观察A组与对照组比较,VAP发生率无统计学意义(P0.05);观察A组与观察B组的口腔清洁率、口腔并发症发生率比较,差异无统计学意义(P0.05),但VAP指标观察B组优于观察A组,差异有统计学意义(P0.05)。结论在实施个体化口腔护理前将气囊压力调高,待口腔护理结束后调整至正常范围,可减少口腔护理过程中冲洗液、口鼻腔内分泌物及气囊上滞留物的反流、误吸,降低VAP的发生率。     

三种不同漱口液对牙龈炎患者牙周指数的影响

目的观察三种不同漱口液对牙龈炎患者牙周指数的影响。方法选取温州市人民医院2013年至2014年收治的单纯性牙龈炎患者60例,随机分成3组,分别使用0.3%双氧水漱口液、0.1%西吡氯铵漱口液及复方氯己定漱口液漱口,检测并记录使用漱口液后2周的牙周指数,观察临床疗效。结果治疗后各组PLI及BI数值均降低,复方氯己定组、西吡氯铵组与双氧水组相比,PLI、BI数值明显偏低(P0.01),但复方氯己定组与西吡氯铵组比较差异无统计学意义(P0.05)。结论三种漱口液均可用作治疗牙龈炎的辅助药物,临床上宜针对性选用避免导致口腔菌群失调。     

幽门螺杆菌在口腔中的特征性分布

目的:研究幽门螺杆菌(Helicobacterpylori,Hp)在慢性胃炎患者口腔中的分布.方法:依据Hp尿素酶C基因和细胞毒素相关基因(cagA)设计引物建立PCR方法,从32例慢性胃炎患者口腔内多部位采集标本,检测和鉴定牙菌斑(每人采集6个牙的龈上和龈下菌斑)、含漱液、舌背黏膜、颊黏膜及腭黏膜表面中的Hp.结果:32例患者中有29例(90.6%)从口腔内牙菌斑、含漱液、舌背黏膜、颊黏膜及腭黏膜至少一处检测出Hp,其中28例(87.5%)从胃和口腔内同时检出Hp,口腔内各部位标本中Hp检出率依次为牙菌斑84.4%,口腔含漱液56.2%,舌背黏膜43.8%,颊黏膜28.1%,腭黏膜9.4%;在384份牙菌斑中,磨牙的牙菌斑Hp的检出率高于前牙(33.2%vs21.9%,P＜0.01);而上下牙的牙菌斑Hp的阳性率差异无显著性(29.7%vs29.2%,P＞0.05);在PD＞4 mm的牙周袋,菌斑Hp检出率显著高于PD＜4 mm的袋(P＜0.05),龈下菌班Hp的阳性率显著高于龈上菌斑(P＜0.01).结论:口腔多部位存在Hp,牙菌斑中居多,并呈一定的分布规律;口腔Hp可能是胃Hp感染的重要来源.     

醋酸氯己定与乙醇的协同杀菌效果

采用悬液定量杀菌试验,对醋酸氯己定与乙醇的协同杀菌效果进行了实验室研究。研究发现,0.1%醋酸氯己定与75%乙醇混合溶液对金黄色葡萄球菌、大肠埃希菌、白假丝酵母菌和黑曲霉均呈现出显著的协同杀菌作用。结果表明,醋酸氯己定与乙醇具有良好的协同杀菌效果。     

复方辛夷滴鼻液联合氯雷他定治疗儿童变应性鼻炎的疗效及对患儿免疫功能指标的影响

目的:研究复方辛夷滴鼻液联合氯雷他定治疗儿童变应性鼻炎的疗效及对患儿免疫功能指标的影响。方法:选取2016年10月至2017年10月在我院接受诊治的126例变应性鼻炎患儿作为研究对象,参照随机数表法分成对照组、研究组,每组各63例。对照组患儿仅接受氯雷他定治疗,研究组患儿接受复方辛夷滴鼻液联合氯雷他定治疗,两组均持续治疗2个月。对比两组患儿的治疗效果及治疗前后CD3~+、CD4~+、CD8~+、CD4~+/CD8~+、血清白细胞介素-4(IL-4)、γ-干扰素(IFN-γ)水平的变化。结果:治疗后,研究组治疗总有效率[95.2%(60/63)]显著高于对照组[81.0%(51/63)],差异有统计学意义(P0.05);两组患儿的CD3~+、CD4~+、CD4~+/CD8~+水平均高于治疗前,且研究组高于对照组,差异有统计学意义(P0.05);两组患儿的CD8~+水平均低于治疗前,且研究组低于对照组,差异有统计学意义(P0.05);两组患儿的血清IL-4水平均低于治疗前,且研究组低于对照组,差异有统计学意义(P0.05);两组患儿的血清IFN-γ水平均高于治疗前,且研究组高于对照组,差异有统计学意义(P0.05)。结论:复方辛夷滴鼻液联合氯雷他定治疗儿童变应性鼻炎的临床效果显著优于单用氯雷他定治疗,其能有效减轻机体炎症水平,提高机体免疫功能。     

右美托米定对慢性阻塞性肺疾病急性加重期患者镇静效果的临床观察

目的:探讨右美托咪定对慢性阻塞性肺疾病急性加重期(AECOPD)患者机械通气的镇静效果和安全性。方法:选取2012年6月-2014年9月在我院接受气管插管呼吸机辅助通气治疗的AECOPD患者62例,并将其随机分为实验组和对照组。其中,对照组患者给予常规治疗,实验组在常规治疗的基础上给予右美托咪镇痛。观察和比较两组患者机械通气持续时间、ICU停住时间、呼吸机相关性肺炎(VAP)、心动过缓和谵妄的发生率。结果:实验组患者机械通气时间及ICU停住时间均明显短于对照组,VAP、心动过缓及谵妄的发生率均显著低于对照组,差异均具有统计学意义(P0.05)。结论:右美托咪定对行机械通气慢性阻塞性肺疾病急性加重期患者良好的镇静效果,且安全性高,值得临床推广。     

An Approximate Solution to the Behrens-Fisher Problem

An approximate and practical solution is proposed for the Behrens-Fisher problem. This solution is compared to the solutions considered by Mehta and Srinivasan (1970) and Welch's (1937) approximate t-test in terms of the stability of the size and magnitude of the power. It is shown that the stability of the size of the new test is better than that of Welch's t when at least one of the sample sizes is small. When the sample sizes are moderately large or large the sizes and powers of all the recommended tests are almost the same.     

A Fragrant Solution to Soil Remediation

The ability of scented geraniums (Pelargonium sp. ‘Frensham’) plants to tolerate, uptake, and accumulate lead was assessed compared with two well-established metal accumulators, Indian mustard (Brassica juncea) and sunflower (Helianthus annuus), under greenhouse conditions. The efficiency of the photosynthetic apparatus and the number and size of active photosynthetic reaction centers (expressed as chlorophyll a fluorescence ratios of variable fluorescence to maximal fluorescence [Fv/Fm] and variable fluorescence to unquenchable portion of fluorescence [Fv/Fo], respectively) were affected to varying degrees at all metal concentrations in all the plants tested. Lead exposure did not significantly affect the efficiency of photosystem II activity or the number and size of the photosynthetic reaction centers in scented geraniums, but the ratios decreased significantly in Indian mustard and sunflower plants following lead exposure. In addition to tolerating high levels of lead, the scented geraniums accumulated in excess of 3000 mg of lead per kg DW of shoot and above 60,000 mg of lead per kg DW of root tissue. Additionally, scented geraniums exposed to a mixture of metals (lead + cadmium + nickel) had the ability to uptake in excess of 4.72% Pb + 0.44% Cd + 0.52% Ni per kg of root DW, as well as 0.17% Pb + 0.07% Cd + 0.14% Ni per kg of shoot DW within 14 d, indicated the potential for existence of more than one functional tolerance and metal uptake mechanism(s). The cellular localization of lead was assessed using transmission electron microscopy coupled with an X-ray microanalyzer. Lead accumulation was observed in the apoplasm and in the cytoplasm, vacuoles, and as distinct globules (potentially as lead-lignin or lead-phosphate complexes) on the cell membrane and cell wall. We conclude that the ability of scented geraniums to tolerate high lead accumulation in its biomass is due, in part, to limiting damage to photosynthetic apparatus and metal detoxification by formation of metal complexes.     

Solution pH modifies the response of Norway spruce seedlings to aluminium

Norway spruce (Picea abies) was exposed to nutrient solutions containing a range of aluminium (Al) concentrations at several pH levels (3.2, 4 and 5). Root growth was reduced by 100 µM and 400 µM Al at pH 4 and 5, but at pH 3.2 only by 400 µM Al. The Al content of the roots increased with increasing pH. The Al content of the roots was higher at the root tips than at the older root parts at all pH values. Using X-ray microanalysis it could be shown that higher levels of Al at increased pH were mainly due to increased Al contents in root cortex cell walls. In seedlings, mycorrhizal with Pisolithus tinctorius or Lactarius rufus, the Al concentration of cortex cell walls was higher when nitrate (NO₃) rather than ammonium (NH₄) was the nitrogen (N) source.     

具有非常数消耗率的Chemostat系统解的稳定性

本文讨论了一类具有非常数消耗率的 Ｃｈｃｍｏｓｔａｔ系统得到解稳定的条件：当 Ａ_１≥ １并且λ_１＜λ_２时,系统在 Ｒ_＋~３内的轨线关于奇点Ｎ１是全局稳定的;当Ａ２≥ １并且λ_１＞λ_２时,系统在Ｒ_＋~３内的轨线关于奇点 Ｎ_２是全局稳定的．     

A Solution to the Challenge of Optimization on 'Golf-Course'-Like Fitness Landscapes

Genetic algorithms (GAs) have been used to find efficient solutions to numerous fundamental and applied problems. While GAs are a robust and flexible approach to solve complex problems, there are some situations under which they perform poorly. Here, we introduce a genetic algorithm approach that is able to solve complex tasks plagued by so-called ''''golf-course''''-like fitness landscapes. Our approach, which we denote variable environment genetic algorithms (VEGAs), is able to find highly efficient solutions by inducing environmental changes that require more complex solutions and thus creating an evolutionary drive. Using the density classification task, a paradigmatic computer science problem, as a case study, we show that more complex rules that preserve information about the solution to simpler tasks can adapt to more challenging environments. Interestingly, we find that conservative strategies, which have a bias toward the current state, evolve naturally as a highly efficient solution to the density classification task under noisy conditions.     

Solution to the phylogenetic enigma of Tetraplatia, a worm-shaped cnidarian

Tetraplatia is a genus containing two species of pelagic cnidarians of curious morphology. Their vermiform shape and four swimming flaps are difficult to relate to the features of other cnidarians, thus obscuring their phylogenetic affinities. Since their discovery in the mid-1800s, a number of prominent cnidarian workers have weighed in on this conundrum, some arguing that they are aberrant hydrozoans and others concluding that they are unusual scyphozoans. Current taxonomic practice conforms to the latter view. However, data presented here from the large and small subunits of the nuclear ribosome leave little doubt that Tetraplatia is in fact a hydrozoan genus. Indeed, its precise phylogenetic position is within Narcomedusae, as some authors had previously deduced based on structural characters. The distinctive body plan of Tetraplatia is remarkable because it appears to have a recent origin, in contrast to the prevailing pattern of metazoan history.     

Osteoprotegerin in Bone Metastases: Mathematical Solution to the Puzzle

Bone is a common site for cancer metastasis. To create space for their growth, cancer cells stimulate bone resorbing osteoclasts. Cytokine RANKL is a key osteoclast activator, while osteoprotegerin (OPG) is a RANKL decoy receptor and an inhibitor of osteoclastogenesis. Consistently, systemic application of OPG decreases metastatic tumor burden in bone. However, OPG produced locally by cancer cells was shown to enhance osteolysis and tumor growth. We propose that OPG produced by cancer cells causes a local reduction in RANKL levels, inducing a steeper RANKL gradient away from the tumor and towards the bone tissue, resulting in faster resorption and tumor expansion. We tested this hypothesis using a mathematical model of nonlinear partial differential equations describing the spatial dynamics of OPG, RANKL, PTHrP, osteoclasts, tumor and bone mass. We demonstrate that at lower expression rates, tumor-derived OPG enhances the chemotactic RANKL gradient and osteolysis, whereas at higher expression rates OPG broadly inhibits RANKL and decreases osteolysis and tumor burden. Moreover, tumor expression of a soluble mediator inducing RANKL in the host tissue, such as PTHrP, is important for correct orientation of the RANKL gradient. A meta-analysis of OPG, RANKL and PTHrP expression in normal prostate, carcinoma and metastatic tissues demonstrated an increase in expression of OPG, but not RANKL, in metastatic prostate cancer, and positive correlation between OPG and PTHrP in metastatic prostate cancer. The proposed mechanism highlights the importance of the spatial distribution of receptors, decoys and ligands, and can be applied to other systems involving regulation of spatially anisotropic processes.