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91.
Klebsiella pneumoniae is an opportunistic pathogen, which causes a wide range of nosocomial infections. Recently, antibiotic resistance makes K. pneumoniae infection difficult to deal with. Investigation on virulence determinants of K. pneumoniae can provide more information about pathogenesis and unveil new targets for treatment or vaccine development. In this study, SitA, a Fur-regulated divalent cation transporter, was found significantly increased when K. pneumoniae was cultured in a nutrient-limited condition. A sitA-deletion strain (ΔsitA) was created to characterize the importance of SitA in virulence. ΔsitA showed higher sensitivity toward hydroperoxide than its parental strain. In a mouse intraperitoneal infection model, the survival rate of mice infected with ΔsitA strain increased greatly when compared with that of mice infected with the parental strain, suggesting that sitA deletion attenuates the bacterial virulence in vivo. To test whether ΔsitA strain is a potential vaccine candidate, mice were immunized with inactivated bacteria and then challenged with the wild-type strain. The results showed that using ΔsitA mutant protected mice better than using the wild-type strain or the capsule-negative congenic bacteria. In summary, SitA was found being important for the growth of K. pneumoniae in vivo and deleting sitA might be a potential approach to generate vaccines against K. pneumoniae.  相似文献   
92.
The sorption of cadmium (II), copper (II), lead (II),manganese (II), and zinc (II) by purified capsularpolysaccharide from the cyanobacterium Microcystis aeruginosafo. flos-aquae strainC3-40 was examined by four methods: equilibriumdialysis, metal removal from solution as detected byvoltammetry, metal accumulation by capsule-containingalginate beads, and calorimetry. The polysaccharide'ssaturation binding capacities for these metals rangedfrom 1.2 to 4 mmol of metal g-1 of capsule, whichcorresponds to 1 metal equivalent per 2 to 4saccharide subunits of the polymer. Competitionbetween paired metals was tested with simultaneous andsequential additions of metal. Cadmium (II) andlead (II), as well as lead (II) and zinc (II), competedrelatively equally and reciprocally for polymerbinding sites. In contrast, manganese (II) stronglyinhibited the binding of cadmium (II) and lead (II), butitself was not substantially inhibited by either theprior or simultaneous adsorption of cadmium (II) or lead (II).The data are interpreted with respect to overlap ofbinding sites and possibilities of altered polymerconformation or solvation. Calorimetric studies oflead (II) and cadmium (II) association reactions withthe polysaccharide suggest that the enthalpies aresmall and that the reactions may be driven by entropy.  相似文献   
93.
目的:观察中药复方天香胶囊对晕动病模型大鼠行为学与前庭核c-fos蛋白表达的影响。方法:选择雄性SD大鼠并将其随机分为正常组、模型组、阳性药组、天香胶囊低、中、高剂量组。灌胃预给药3天后,采用双轴旋转刺激法建立大鼠晕动病模型,通过晕反应指数评分、自发活动实验、异嗜高岭土实验检测各组大鼠行为学变化,Western blotting法与免疫组化法检测各组大鼠前庭核c-fos蛋白的表达。结果:与正常组大鼠相比,模型组大鼠晕反应指数和高岭土摄入量均显著增高,自发活动总路程与次数均显著减少,前庭核c-fos蛋白表达水平显著增高;与模型组相比,天香胶囊可显著降低晕动病模型大鼠晕反应指数与高岭土摄入量,提高自发活动总路程与活动次数,降低大鼠前庭核组织c-fos蛋白表达。结论:天香胶囊可有效改善晕动病模型大鼠的行为学变化,其作用机制可能与下调前庭核c-fos表达有关,提示降低前庭核兴奋性可能是天香胶囊抗晕动病的内在机制之一。  相似文献   
94.
摘要 目的:观察舒肝解郁胶囊联合阿戈美拉汀治疗抑郁症的疗效及对血清单胺类神经递质和神经功能相关因子的影响。方法:纳入我院2017年5月~2020年5月接诊的120例抑郁症患者,经双色球随机分组法将患者分为对照组和观察组,各为60例。对照组患者予以阿戈美拉汀治疗,观察组患者予以舒肝解郁胶囊联合阿戈美拉汀治疗。比较两组疗效、血清单胺类神经递质、神经功能相关因子、抑郁焦虑评分及不良反应发生率。结果:观察组的临床总有效率为93.33%(56/60),高于对照组的73.33%(44/60)(P<0.05)。两组治疗6周后汉密尔顿抑郁量表(HAMD)、汉密尔顿焦虑量表(HAMA)评分较治疗前降低,且观察组较对照组低(P<0.05)。两组治疗6周后多巴胺(DA)、去甲肾上腺素(NE)、5-羟色胺(5-HT)水平较治疗前升高,且观察组高于对照组(P<0.05)。两组治疗6周后S100?茁、髓磷脂碱性蛋白(MBP)、神经元特异性烯醇化酶(NSE)水平较治疗前降低,且观察组低于对照组(P<0.05)。两组不良反应发生率对比无差异(P>0.05)。结论:舒肝解郁胶囊联合阿戈美拉汀治疗抑郁症,疗效显著,可有效调节血清单胺类神经递质和神经功能,改善抑郁症状,且安全可靠。  相似文献   
95.
摘要 目的:探讨龙血竭胶囊合九华膏对环状混合痔(RMH)术后患者创面愈合、血清炎性因子和免疫功能的影响。方法:选取2016年7月~2019年12月期间我院收治的RMH患者93例,根据随机数字表法分为对照组(n=46,马应龙麝香痔疮膏治疗)和研究组(n=47,龙血竭胶囊合九华膏治疗),比较两组患者疗效、创面愈合情况、不良反应、血清炎性因子和免疫功能。结果:治疗10 d后,研究组的临床总有效率为89.36%(42/47),高于对照组的71.74%(33/46)(P<0.05)。两组治疗10 d后创面渗液、水肿、疼痛、创面肉芽组织评分下降,创面面积减小,且研究组低于对照组(P<0.05)。两组治疗10 d后肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)、白介素-2(IL-2)均下降,且研究组低于对照组(P<0.05)。两组治疗10 d后免疫球蛋白G(IgG)、免疫球蛋白A(IgA)、免疫球蛋白M(IgM)均升高,且研究组高于对照组(P<0.05)。研究组并发症发生率低于对照组(P<0.05)。结论:RMH患者术后采用龙血竭胶囊合九华膏治疗,疗效较好,可有效促进创面愈合,减轻炎症反应,改善机体免疫功能,同时还可减少并发症发生率。  相似文献   
96.
摘要 目的:探讨肾康注射液联合羟苯磺酸钙胶囊对原发性肾病综合征(PNS)并发急性肾损伤(AKI)患者肾功能、凝血功能及炎性因子的影响。方法:选取2018年4月~2019年11月期间我院收治的134例PNS合并AKI患者,随机分为对照组(常规治疗基础上予以羟苯磺酸钙胶囊治疗)和联合组(对照组基础上予以肾康注射液治疗),各67例。治疗14 d后,对比两组患者疗效、肾功能指标[尿素氮(BUN)、血肌酐(Scr)、白蛋白(Alb)]、凝血功能指标[凝血酶时间(TT)、凝血酶原时间(PT)、活化部分凝血酶原时间(APTT)、纤维蛋白原(FIB)]及炎性因子[白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、C反应蛋白(CRP)],记录两组不良反应情况。结果:联合组治疗14d后的临床总有效率高于对照组(P<0.05)。治疗14 d后,两组PT、APTT、TT、FIB、Scr、BUN、IL-6、TNF-α、CRP均较治疗前下降,且联合组低于对照组(P<0.05)。治疗14 d后,两组Alb升高,且联合组高于对照组(P<0.05)。对照组、联合组的不良反应总发生率对比未见统计学差异(P>0.05)。结论:相较于羟苯磺酸钙胶囊单药治疗,PNS合并AKI患者在羟苯磺酸钙胶囊的基础上联合肾康注射液治疗,可有效减轻肾功能损害,改善凝血功能,降低炎性因子水平,疗效明显,且未增加严重不良反应。  相似文献   
97.
张国华 《生物磁学》2005,5(4):35-36
目的:观察步长稳心颗粒(简称稳心颗粒)治疗功能性早搏的临床疗效及安全性。方法:选择功能性早搏60例病人,随机分为治疗组及对照组,每组各30例。治疗组给予稳心颗粒一包(9克),每日三次,温开水冲服;对照组给予倍他乐克25毫克,每日二次口服,一个月为一疗程。结果:四周后治疗组显效11例,有效16例,总有效率90%。对照组显效8例,有效18例,总有效率86.7%,p〉0.05,两组比较无显著性差异。对血压、心率影响方面稳心颗粒明显优于倍他乐克结论:稳心颗粒治疗功能性早搏疗效显著,且效果稳定,安全无明显不良反应,值得临床推广应用。  相似文献   
98.
姜楠  刘晓光  潘皎  王雅洁  朱旭东 《微生物学报》2009,49(11):1459-1464
摘要:【目的】新型隐球酵母是人类条件致病真菌,主要感染免疫缺陷患者。该酵母最显著的特征是细胞外包被主要的致病因子-多糖荚膜,其调控机制复杂。本文研究旨在阐述编码铜依赖转录因子的CUF1基因对其荚膜生物合成的负调控作用。【方法】以野生型菌株为对照,对CUF1缺失的突变菌株进行菌落形态观察、荚膜墨汁染色的显微观察、细胞聚沉试验以及荚膜定量分析。【结果】与野生型菌株相比,Δcuf1突变株产生的菌落更粘,显微镜下亦可明显观察到荚膜更厚。同样数量的细胞,突变株聚沉平衡后体积更大。此外,荚膜粗提物定量称重分析也证明突  相似文献   
99.
Soil and groundwater contamination by organic substances is a major environmental and health concern, but methods of direct, in situ evaluation of quantities and forms of these contaminants are generally highly limited. The resin capsule system (RCS) has been developed for use in the laboratory or in the field for inorganic chemicals, and its application has been extended to include organic chemicals by incorporation of carbonaceous, hydrophobic adsorbers in the capsules. The objective of this study was to determine the efficacy of carbonaceous resin capsules for detecting benzene, toluene, ethylbenzene, and xylene (BTEX) vapors diffusing through a soil column, and to investigate sensitivity to environmental factors that influence vapor phase diffusion. Results show that the RCS can serve as a trap for organic vapors, and that quantities of BTEX accumulated are influenced by soil texture and water content during extended adsorption times. The nature of these effects, as measured by the RCS, was similar to expectations, based on previously reported results from studies involving direct measurements. These results provide evidence that the RCS could be developed to serve as a simple, inexpensive, direct, in situ methodology for monitoring volatile organic chemicals in soils.  相似文献   
100.
The glenohumeral joint is the most frequently dislocated major joint in the body, and instability due to permanent deformation of the glenohumeral capsule is a common pathology. The corresponding change in mechanical properties may have implications for the ideal location and extent of plication, which is a common clinical procedure used to repair the capsule. Therefore, the objective of this study was to quantify the mechanical properties of four regions of the glenohumeral capsule after anterior dislocation and compare the properties to the normal glenohumeral capsule. Six fresh-frozen cadaveric shoulders were dislocated in the anterior direction with the joint in the apprehension position using a robotic testing system. After dislocation, mechanical testing was performed on the injured glenohumeral capsule by loading the tissue samples in tension and shear. An inverse finite element optimization routine was used to simulate the experiments and obtain material coefficients for each tissue sample. Cauchy stress–stretch curves were then generated to represent the mechanical response of each tissue sample to theoretical loading conditions. Based on several comparisons (average of the material coefficients, average stress–stretch curve for each region, and coefficients representing the average curves) between the normal and injured tissue samples, the mechanical properties of the injured tissue samples from multiple regions were found to be lower than those of the normal tissue in tension but not in shear. This finding indicates that anterior dislocation primarily affects the tensile behavior of the glenohumeral capsule rather than the shear behavior, and this phenomenon could be caused by plastic deformation of the matrix, permanent collagen fiber rotation, and/or collagen fiber failure. These results suggest that plication and suturing may not be sufficient to return stability to the shoulder after dislocation in all individuals. Thus, surgeons may need to perform a procedure that reinforces or stiffens the tissue itself, such as reconstruction or augmentation, to improve repair procedures.  相似文献   
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