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101.
目的了解吴江地区临床分离多重耐药鲍曼不动杆菌(MDRAB)碳青霉烯酶基因携带情况和同源性。方法收集吴江地区3所综合性医院2010年1月—2013年12月临床分离的非重复MDRAB 44株,测定其最低抑菌浓度(MIC);采用聚合酶链反应(PCR)扩增碳青霉烯酶基因OXA 51、OXA 23、OXA 24、OXA 58、IMP、TEM、SHV和GES,脉冲场凝胶电泳(PFGE)分析菌株同源性。结果44株MDRAB主要来源标本为痰(占93.18%),主要分布在重症监护病房(ICU)、呼吸科和神经外科,各占45.45%、27.27%和13.64%;MDRAB对米诺环素和多粘菌素B均敏感,对哌拉西林、氨苄西林/舒巴坦、头孢他啶、庆大霉素、阿米卡星、环丙沙星耐药率均为100.00%,对亚胺培南和美罗培南耐药率均为97.73%。44株MDRAB均检出OXA 51、OXA 23和TEM基因,其中12株菌GES基因阳性,OXA 58和SHV基因阳性各1株,未检测到OXA 24及IMP基因;MDRAB分为A—G 7个型别,分别为19、3、9、3、1、4、5株。A型主要来源于吴江地区的两所大型综合性医院(吴江第一人民医院和盛泽医院),吴江第一人民医院未发现B、D和E型;E型仅1株,分布在永鼎医院,其余型别散在分布。结论吴江地区临床分离鲍曼不动杆菌多重耐药严重,基因OXA 23和TEM是鲍曼不动杆菌多重耐药的主要原因,并以A、C型为主,呈克隆性传播。  相似文献   
102.
目的:探讨强脉冲光对面部雀斑的治疗效果.方法:采用强脉冲光治疗仪波长为560nm~1 200nm滤光片治疗181例面部雀斑病变患者,治疗4次~5次,每次时间间隔为3周,每位患者进行对比拍照、记录参数并进行临床疗效评估.结果:181例雀斑患者的显效率为:99.44%(180/181).结论:强脉冲光对雀斑有良好的疗效.  相似文献   
103.
Multisensor CMMs are systems with an established position on the market, but their popularity still grows, as they provide access to the advantages offered by tactile and contactless measurement methods. Yet there are still questions of the comparability of results obtained using the optical and tactile operation modes of multisensor system. This phenomenon can be assessed by measuring appropriate gauges, most often reference rings or spheres. Due to the completely different nature of probing processes for tactile and contactless measurements, the material from which reference object is made may significantly affect measurement results. In order to assess the influence of this factor on measurement accuracy, three reference spheres made from different materials were measured on optical multisensor CMMs. Measurements involved tactile measurements as well as optical measurements made using different probing systems: a video probe and white light sensor. Results obtained from performed experiments show large differences depending on the material used for spherical standard production. On the basis of obtained results, it can be stated that the best material for a reference object that can be used for comparability tests of tactile and optical measurements is a composite of alumina with at least one oxidic additive.  相似文献   
104.
The present work aims to study the photocatalytic properties of nanohybrids composed of silicon nanowires (SiNWs) decorated with PbS nanoparticles (NPs). The elaborated material was intended to be utilized in wastewater treatment. The SiNWs were elaborated from the Metal Assisted Chemical Etching route (MACE), while the PbS NPs were deposited at room temperature onto SiNWs using the pulsed laser deposition (PLD) technique. The influence of decorating SiNWs (having different lengths) with PbS-NPs on their structural, morphological, optoelectronic, and photocatalytic properties was scrutinized. PbS/SiNWs nanohybrids exhibited enhanced photocatalytic degradation towards Black Amido (BA) dye for 20 µm SiNWs length and 0.2% of BA volume concentration. These optimized conditions may insinuate that this nanocomposite-like structure is a promising efficient photocatalytic systems contender, cost-effective, and recyclable for organic compound purification from wastewaters.  相似文献   
105.
Aging is by far the most prominent risk factor for Alzheimer's disease (AD), and both aging and AD are associated with apparent metabolic alterations. As developing effective therapeutic interventions to treat AD is clearly in urgent need, the impact of modulating whole-body and intracellular metabolism in preclinical models and in human patients, on disease pathogenesis, have been explored. There is also an increasing awareness of differential risk and potential targeting strategies related to biological sex, microbiome, and circadian regulation. As a major part of intracellular metabolism, mitochondrial bioenergetics, mitochondrial quality-control mechanisms, and mitochondria-linked inflammatory responses have been considered for AD therapeutic interventions. This review summarizes and highlights these efforts.  相似文献   
106.
Parkin, an E3 ubiquitin ligase, plays a role in maintaining mitochondrial homeostasis through targeting damaged mitochondria for mitophagy. Accumulating evidence suggests that the acetylation modification of the key mitophagy machinery influences mitophagy level, but the underlying mechanism is poorly understood. Here, our study demonstrated that inhibition of histone deacetylase (HDAC) by treatment of HDACis activates mitophagy through mediating Parkin acetylation, leading to inhibition of cervical cancer cell proliferation. Bioinformatics analysis shows that Parkin expression is inversely correlated with HDAC2 expression in human cervical cancer, indicating the low acetylation level of Parkin. Using mass spectrometry, Parkin is identified to interact with two upstream molecules, acetylase acetyl-CoA acetyltransferase 1 (ACAT1) and deacetylase HDAC2. Under treatment of suberoylanilide hydroxamic acid (SAHA), Parkin is acetylated at lysine residues 129, 220 and 349, located in different domains of Parkin protein. In in vitro experiments, combined mutation of Parkin largely attenuate the interaction of Parkin with PTEN induced putative kinase 1 (PINK1) and the function of Parkin in mitophagy induction and tumor suppression. In tumor xenografts, the expression of mutant Parkin impairs the tumor suppressive effect of Parkin and decreases the anticancer activity of SAHA. Our results reveal an acetylation-dependent regulatory mechanism governing Parkin in mitophagy and cervical carcinogenesis, which offers a new mitophagy modulation strategy for cancer therapy.  相似文献   
107.
近年来,以低强度脉冲式超声波(LIPUS)为代表的机械力治疗手段已被广泛用于康复医学、骨折修复、神经损伤修复、泌尿系统疾病等领域.目前研究表明,LIPUS可能通过激活内源性干细胞参与组织修复,但是机械力如何通过生物链的转化而激活干细胞的具体机制尚不明确,因此对机械力生物链传导过程的进一步探索有助于揭示LIPUS的作用机...  相似文献   
108.
The gas-phase reaction dynamics and kinetics in a laser induced plasma are very much dependent on the interactions of the evaporated target material and the background gas. For metal (M) and metal–oxygen (MO) species ablated in an Ar and O2 background, the expansion dynamics in O2 are similar to the expansion dynamics in Ar for M+ ions with an MO+ dissociation energy smaller than O2. This is different for metal ions with an MO+ dissociation energy larger than for O2. This study shows that the plume expansion in O2 differentiates itself from the expansion in Ar due to the formation of MO+ species. It also shows that at a high oxygen background pressure, the preferred kinetic energy range to form MO species as a result of chemical reactions in an expanding plasma, is up to 5 eV.  相似文献   
109.
BackgroundSalivary free light chains (FLCs) are an emerging biomarker in health and behavioural research. However, little is known regarding biological variability of salivary FLCs and how they relate to other established salivary biomarkers. This study aimed to investigate the diurnal and day-to-day variation of salivary FLCs and their relationship with salivary IgA and steroid hormones.MethodsA total of 46 healthy adults participated in studies exploring the biological variability of FLCs. Diurnal variation was investigated by collecting saliva samples immediately upon waking, 0.5 h, 3 h, 6 h, 9 h and 14 h post-waking. Saliva samples were assessed for FLCs, IgA, cortisol and dehydroepiandrosterone (DHEA). Between-day variation in FLCs and IgA was assessed by collecting saliva samples immediately upon waking for seven consecutive days. Participants underwent a dental examination to exclude oral health as a potential confounding variable. Within and between-person day-to day variation was explored in relation to a range of different factors: awakening time, sleep, exercise, well-being and alcohol consumption.ResultsSalivary secretion rates of FLCs decreased following waking and up to 3 h post-waking and then plateaued. This same pattern was observed for IgA. DHEA was stable upon waking and higher levels were seen in the morning with significantly lower levels thereafter. Cortisol levels significantly increased 0.5 h post-waking then continued to decline across the day. FLCs were significantly correlated with IgA but not cortisol or DHEA. Both FLCs and IgA parameters showed day-to-day variability, with coefficients of variation ≥ 40%. Earlier waking time was significantly correlated with higher FLC and IgA secretion rates. Inter-person differences in saliva parameter variability were observed but the degree of variation in FLCs and IgA was related within person. Inter-person day-to-day variation appeared to be uninfluenced by lifestyle or behavioural factors.ConclusionsSaliva FLCs secretion exhibits diurnal fluctuation that mirrors IgA fluctuation. Findings strongly indicate salivary FLC secretion is orchestrated by local plasma cells. FLCs and IgA both showed notable variability day-to-day, which was similar within person and influenced by awakening time. FLCs offer a promising adjunct to IgA in the measurement of oral immune activation.  相似文献   
110.
目的采用高效液相色谱-蒸发光散射检测方法(HPLC-ELSD)建立同时测定知母药材中新芒果苷、芒果苷、知母皂苷BⅡ、宝藿苷Ⅰ及知母皂苷AⅢ的含量测定方法。方法采用Agilent poroshell 120 EC-C18柱,流动相采用乙腈-0.2%醋酸水系统,梯度洗脱;柱温为30℃,流速为0.7 ml/min;蒸发光散射检测器以氮气为雾化气,雾化气温度为40℃,漂移管温度为90℃,氮气体积流量为2.0 L/min;进样量为20μl。结果 5种成分均能达到基线分离,新芒果苷24.1~386μg/ml(r=0.999 3)、芒果苷23.2~371μg/ml(r=0.998 6)、知母皂苷BⅡ54.2~867.2μg/ml(r=0.995 6)、宝藿苷Ⅰ5.3~84.8μg/ml(r=0.996 8)、知母皂苷AⅢ10~160μg/ml(r=0.998 9)的浓度范围内呈现良好的线性关系。5种成分的平均加样回收率在101.8%~105.0%之间,重复性RSD小于2.4%,知母药材中上述5种成分含量分别为1.62%、0.82%、7.36%、0.07%、0.34%。结论该方法...  相似文献   
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