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991.
目的研究妇科疾病患者外周静脉植进中心静脉导管(PICC)后感染者病原菌分布及T淋巴细胞亚群水平变化。方法选取2017年3月至2019年5月在我院接受PICC置管治疗的63例妇科疾病患者为观察组,另外选取同期我院健康体检女性50例为对照组,采用菌种分离鉴定法分析观察组患者病原菌分布,并比较观察组和对照组对象T淋巴细胞亚群和白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)水平。结果共分离出102株细菌,其中以大肠埃希菌(19.61%)、肺炎克雷伯菌(14.71%)、铜绿假单胞菌(9.80%)为主的革兰阴性菌占比最高(50.98%);其次是革兰阳性菌,占34.31%;真菌数量最少,占14.71%。感染前后观察组患者CD3~+细胞、CD4~+细胞及CD4~+/CD8~+水平显著低于对照组(均P0.05),而CD8~+细胞及IL-6、TNF-α水平显著高于对照组对象(均P0.05)。感染后,观察组患者CD3~+细胞、CD4~+细胞及CD4~+/CD8~+水平显著低于感染前,CD8~+细胞及IL-6、TNF-α水平显著高于感染前(均P0.05)。结论妇科疾病患者PICC置管后感染者病原菌以大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌等革兰阴性菌为主,感染后患者T淋巴细胞亚群及炎性因子水平严重失调,患者免疫功能减弱。  相似文献   
992.
Jiao  Zexin  Tian  Yuan  Hu  Boyang  Li  Qi  Liu  Shikai 《Marine biotechnology (New York, N.Y.)》2021,23(5):736-748
Marine Biotechnology - The Pacific oyster (Crassostrea gigas) genome is highly polymorphic and affluent in structural variations (SVs), a significant source of genetic variation underlying...  相似文献   
993.
Interactions between plant hosts and their microbiotas are becoming increasingly evident, while the effects of plant communities on microbial communities in different geographic environments are poorly understood. Here, the differentiation of licorice plant ecotypes and the distribution of root-associated microbiotas were investigated across five sampling sites in northwest China. The interactions between the environment, plant and microbial communities, and their effects on licorice root secondary metabolites, were elucidated. The plant community was clearly differentiated into distinct ecotypes based on genotyping-by-sequencing and was primarily driven by geographic distance and available soil nitrogen. The bulk soil and root-associated microbiotas (rhizosphere soil and root endosphere) partially correlated with plant community, but all were significantly discriminated by plant clade. Moreover, these microbiotas were explained to different extents by distinct combinations of environment, geography, and plant community. Similarly, three structural equation models showed that licorice root secondary metabolites were complicatedly modulated by multiple abiotic and biotic factors, and were mostly explained by these factors in the rhizosphere model. Collectively, the results provide novel insights into the role of environment–plant–microbiota interactions in regulating root secondary metabolites. That should be accounted for when selecting appropriate licorice planting sites and management measures.  相似文献   
994.
Zhang  Xi  Man  Yi  Zhuang  Xiaohong  Shen  Jinbo  Zhang  Yi  Cui  Yaning  Yu  Meng  Xing  Jingjing  Wang  Guangchao  Lian  Na  Hu  Zijian  Ma  Lingyu  Shen  Weiwei  Yang  Shunyao  Xu  Huimin  Bian  Jiahui  Jing  Yanping  Li  Xiaojuan  Li  Ruili  Mao  Tonglin  Jiao  Yuling  Sodmergen  Ren  Haiyun  Lin  Jinxing 《中国科学:生命科学英文版》2021,64(9):1392-1422
In multicellular and even single-celled organisms, individual components are interconnected at multiscale levels to produce enormously complex biological networks that help these systems maintain homeostasis for development and environmental adaptation. Systems biology studies initially adopted network analysis to explore how relationships between individual components give rise to complex biological processes. Network analysis has been applied to dissect the complex connectivity of mammalian brains across different scales in time and space in The Human Brain Project. In plant science, network analysis has similarly been applied to study the connectivity of plant components at the molecular, subcellular, cellular, organic, and organism levels. Analysis of these multiscale networks contributes to our understanding of how genotype determines phenotype. In this review, we summarized the theoretical framework of plant multiscale networks and introduced studies investigating plant networks by various experimental and computational modalities. We next discussed the currently available analytic methodologies and multi-level imaging techniques used to map multiscale networks in plants. Finally, we highlighted some of the technical challenges and key questions remaining to be addressed in this emerging field.  相似文献   
995.
With the development of social media, the information about vector-borne disease incidence over broad spatial scales can cause demand for local vector control before local risk exists. Anticipatory intervention may still benefit local disease control efforts; however, infection risks are not the only focal concerns governing public demand for vector control. Concern for environmental contamination from pesticides and economic limitations on the frequency and magnitude of control measures also play key roles. Further, public concern may be focused more on ecological factors (i.e., controlling mosquito populations) or on epidemiological factors (i.e., controlling infection-carrying mosquitoes), which may lead to very different control outcomes. Here we introduced a generic Ross-MacDonald model, incorporating these factors under three spatial scales of disease information: local, regional, and global. We tailored and parameterized the model for Zika virus transmitted by Aedes aegypti mosquito. We found that sensitive reactivity caused by larger-scale incidence information could decrease average human infections per patch breeding capacity, however, the associated increase in total control effort plays a larger role, which leads to an overall decrease in control efficacy. The shift of focal concerns from epidemiological to ecological risk could relax the negative effect of the sensitive reactivity on control efficacy when mosquito breeding capacity populations are expected to be large. This work demonstrates that, depending on expected total mosquito breeding capacity population size, and weights of different focal concerns, large-scale disease information can reduce disease infections without lowering control efficacy. Our findings provide guidance for vector-control strategies by considering public reaction through social media.  相似文献   
996.
Yu C  Li L  Chen W  Jiao Y  Yang N  Yang E  Zhang J  Chen L  Li Y 《Helicobacter》2011,16(2):119-123
Background: The aims of this study were to compare disk diffusion with E‐test method for levofloxacin susceptibility testing of Helicobacter pylori and standardized breakpoints for disk diffusion as a stable and reliable method for determining qualitative levofloxacin susceptibility. Materials and Methods: We determined the levofloxacin susceptibility of 45 H. pylori strains isolated from Chinese patients by the E‐test method. Disk diffusion was evaluated as an alternative method to determine susceptibility and compared with the E‐test results by linear regression analysis. Results: The minimum inhibitory concentration (MIC) values tested by E‐test method ranged from 0.047 to 32 μg/mL. Resistance to levofloxacin was detected in 16 (35.6%) isolates. The levofloxacin disk zone sizes obtained by disk diffusion method correlated well (r2 = .877) with the MICs obtained by E‐test method. As a consequence of regression analysis, isolates with inhibition diameters <12 mm were considered resistant to levofloxacin. There was 100% agreement between the two methods for levofloxacin, applying the regression‐based breakpoints. Conclusions: The disk diffusion method is equivalent to the E‐test method for testing levofloxacin susceptibility of H. pylori strains; it is more practical and inexpensive, and it is suitable for the analysis of a small number of isolates compared with the E‐test method.  相似文献   
997.
This study was to explore whether repeated non-invasive limb ischemic pre-conditioning (NLIP) can confer an equivalent cardioprotection against myocardial ischemia-reperfusion (I/R) injury in acute diabetic rats to the extent of conventional myocardial ischemic pre-conditioning (MIP) and whether or not the delayed protection of NLIP is mediated by reducing myocardial oxidative stress after ischemia-reperfusion. Streptozotocin-induced diabetic rats were randomized to four groups: Sham group, the I/R group, the MIP group and the NLIP group. Compared with the I/R group, both the NLIP and MIP groups showed an amelioration of ventricular arrhythmia, reduced myocardial infarct size, increased activities of total superoxide dismutase (SOD), manganese-SOD and glutathione peroxidase, increased expression of manganese-SOD mRNA and decreased xanthine oxidase activity and malondialdehyde concentration (All p < 0.05 vs I/R group). It is concluded that non-invasive limb ischemic pre-conditioning reduces oxidative stress and attenuates myocardium ischemia-reperfusion injury in diabetic rats.  相似文献   
998.
999.
目的构建变形链球菌UAl59密度感应相关的comD基因缺陷菌株,为进一步研究该基因功能做准备。方法根据同源重组原理,利用变形链球菌UAl59comD基因同源重组DNA片段,采用电击转化方法获取转化菌落,通过形态学观察、生化特性检测、PCR及测序、RT-PCR对缺陷菌进行鉴定。结果在含有红霉素(10μg/mL)的琼脂平板上出现转化菌落,鉴定结果均显示转化菌为comD缺陷菌。结论成功构建了变形链球菌UA159comD基因缺陷菌株。  相似文献   
1000.
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