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971.
972.
目的:研究胸腔镜食管癌切除术后肺部感染患者肺功能和炎症因子水平的关系。方法:选取2015年3月~2018年7月我院收治的食管癌患者120例为研究对象,将其以随机数字表法分成对照组和观察组。对照组予以传统开胸手术治疗,观察组则予以胸腔镜食管切除术治疗。分别比较两组术后肺部感染发生情况、手术前后肺功能以及炎症因子水平变化情况,并分析胸腔镜食管癌切除术后肺部感染患者肺功能与炎症因子的关系。结果:观察组患者术后肺部感染发生率为13.33%(8/60),低于对照组的36.67%(22/60),差异有统计学意义(P0.05)。术后观察组用力肺活量(FVC)、第1秒用力呼气量(FEV1)、FEV1/FVC均高于对照组,差异均有统计学意义(均P0.05)。术后1 d、术后5 d观察组白细胞介素-6(IL-6)、白细胞介素-10(IL-10)以及C反应蛋白(CRP)水平均低于对照组,差异均有统计学意义(均P0.05)。经Pearson相关性分析可得:胸腔镜食管癌切除术后肺部感染患者FVC、FEV1、FEV1/FVC与IL-6、IL-10、CRP均呈负相关性(均P0.05)。结论:胸腔镜食管癌切除术可显著降低患者肺部感染发生风险,且术后肺部感染患者肺功能与炎症反应存在密切相关,降低术后肺部感染发生率的机制可能与减轻机体炎症反应有关。  相似文献   
973.
Clostridium beijerinckii optinoii is a Clostridium species that produces butanol, isopropanol and small amounts of ethanol. This study compared the performances of batch and continuous immobilized cell fermentations, investigating how media flow rates and nutritional modification affected solvent yields and productivity. In 96-h batch cultures, with 80 % of the 30 g L?1 glucose consumed in synthetic media, solvent concentration was 9.45 g L?1 with 66.0 % as butanol. In a continuous fermentation using immobilized C. beijerinckii optinoii cells, also with 80 % of 30 g L?1 glucose utilization, solvent productivity increased to 1.03 g L?1 h?1. Solvent concentration reached 12.14 g L?1 with 63.0 % as butanol. Adjusting the dilution rate from 0.085 to 0.050 h?1 to allow extended residence time in column was required when glucose concentration in fresh media was increased from 30 to 50 g L?1. When acetate was used to improve the buffer capacity in media, the solvent concentration reached 12.70 on 50 g L?1 glucose. This continuous fermentation using immobilized cells showed technical feasibility for solvent production.  相似文献   
974.
Objectives: To provide a simple method to make a stable ΔF508-CFTR-expressing T84 cell line that can be used as an efficient screening model system for ΔF508-CFTR rescue. Results: CFTR knockout cell lines were generated by Cas9 with a single-guide RNA (sgRNA) targeting exon 1 of the CFTR genome, which produced indels that abolished CFTR protein expressions. Next, stable ΔF508-CFTR expression was achieved by genome integration of ΔF508-CFTR via the lentivirus infection system. Finally, we showed functional rescue of ΔF508-CFTR not only by growing the cells at a low temperature, but also incubating with VX-809, a ΔF508-CFTR corrector, in the established T84 cells expressing ΔF508-CFTR. Conclusions: This cell system provides an appropriate screening platform for rescue of ΔF508-CFTR, especially related to protein folding, escaped from endoplasmic-reticulum-associated protein degradation, and membrane transport.  相似文献   
975.
976.
类黄酮3′-羟化酶(Flavonoid 3′-hydroxylase,F3′H)是细胞色素P450单加氧酶,在花青素合成途径中催化二氢山奈酚生成二氢槲皮素,进而形成矢车菊色素。利用津田芜菁BrF3′H1和赤丸芜菁BrF3′H2基因构建过量表达载体后遗传转化烟草,转基因植株的花色加深。通过染色体步移法克隆了BrF3′H1和BrF3′H2基因上游846和851 bp的启动子序列。生物信息学分析表明,BrF3′H1P和BrF3′H2P均包含TATA box、CAAT box、光调控元件、MRE、ABRE、ATGCAAAT-motif、ERE、O2-site、RY-element、LTR等多个顺式作用元件;二者的核苷酸序列在7个位点存在差异。利用BrF3′H1P和BrF3′H2P序列替换pCAMBIA1301植物表达载体的35S启动子后遗传转化烟草。GUS组织化学染色结果表明,BrF3′H1P和BrF3′H2P序列均能驱动GUS基因表达。通过PCR方法获得了BrF3′H1P和BrF3′H2P的一系列缺失片段,融合GUS基因后转化烟草。染色结果显示,BrF3′H1P和BrF3′H2P系列缺失片段均具有起始GUS基因表达的活性。BrF3′H1和BrF3′H2基因的功能鉴定及启动子的初步分析将为揭示津田芜菁和赤丸芜菁F3′H基因的光诱导表达调控机理奠定研究基础。  相似文献   
977.

Background

Although non-alcoholic fatty liver disease is the hepatic manifestation of metabolic syndrome, its influence on hypertension development is poorly understood. We investigated whether fatty liver disease, as assessed by the fatty liver index, could predict the development of hypertension independently of systemic insulin resistance, inflammatory status and adipokine levels.

Methods

Prospective cohort study of 1,521 adults (484 men and 1037 women) aged 40 to 70 years without baseline hypertension examined. An equation was used to calculate fatty liver index and classify patients as follows: fatty liver index <30, no non-alcoholic fatty liver disease; fatty liver index ≥60, non-alcoholic fatty liver disease; and 30≤ fatty liver index <60, intermediate fatty liver index.

Results

During an average of 2.6 years of follow-up, 153 subjects (10.06%) developed hypertension. Fatty liver index was positively associated with baseline blood pressure, homeostasis model assessment of insulin resistance, urinary albumin/creatinine excretion, and high sensitivity C-reactive protein. After adjustment for confounding factors, including markers of insulin resistance, systemic inflammation and adiponectin levels, the odds ratio [95% confidence interval] for the incident hypertension increased in a graded manner with fatty liver index (<30 vs. 30–59 vs. ≥60 = 1 vs. 1.83 [1.16~2.88] vs. 2.09 [1.08~4.055], respectively).

Conclusions

Non-alcoholic fatty liver disease assessed by fatty liver index was an independent risk factor for hypertension. Our findings suggest that fatty liver index, a simple surrogate indicator of fatty liver disease, might be useful for identifying subjects at high risk for incident hypertension in clinical practice.  相似文献   
978.
Understanding the dynamics of evolution of Follicular Lymphoma (FL) clones during disease progression is important for monitoring and targeting this tumor effectively. Genetic profiling of serial FL biopsies and examples of FL transmission following bone marrow transplant suggest that this disease may evolve by divergent evolution from a common ancestor cell. However where this ancestor cell resides and how it evolves is still unclear. The analysis of the pattern of somatic hypermutation of the immunoglobulin gene (Ig) is traditionally used for tracking the physiological clonal evolution of B cells within the germinal center and allows to discriminate those cells that have just entered the germinal center and display features of ancestor cells from those B cells that keep re-circulating across different lymphoid organs. Here we investigated the pattern of somatic hypermutation of the heavy chain of the immunoglobulin gene (IgH-VH) in 4 flow-sorted B cells subpopulations belonging to different stages of differentiation, from sequential lymph node biopsies of cases displaying diverse patterns of evolution, using the GS-FLX Titanium sequencing platform. We observed an unexpectedly high level of clonality, with hundreds of distinct tumor subclones in the different subpopulations from the same sample, the majority detected at a frequency <10−2. By using a lineage trees analysis we observed in all our FL and t-FL cases that the oligoclonal FL population was trapped in a narrow intermediate stage of maturation that maintains the capacity to undergo SHM, but was unable to further differentiate. The presence of such a complex architecture highlights challenges currently encountered in finding a cure for this disease.  相似文献   
979.
Unrelated male primates frequently cohabit in bisexual groups and, despite being reproductive competitors, have been shown to cooperate in ways that are associated with reproductive success. Such coalitions between males are common in some taxa, where they can serve two primary functions – status management and improved mating opportunities – that subserve long‐ and short‐term objectives. Here, we use observational data to provide information on male coalitions in vervet monkeys (Chlorocebus pygerythrus), a guenon with a multimale group structure. We recorded a total of 62 coalitions from two troops across a 10‐mo period at Samara Game Reserve, South Africa. We found that males who were more frequently associated spatially and who had groomed one another were more likely to form coalitions and did so against higher‐ranking opponents. This was not linked to any evidence that coalitionary aggression provided either short‐ or long‐term reproductive benefits for the aggressors and coalitions were not restricted to the mating season. There was little evidence that particular individuals were targeted, reciprocation between partners was not observed, and recent immigrant males were not targeted disproportionately. Our data suggest that within‐group coalition formation between vervet males may represent something close to an ancestral state whereby males form ad hoc coalitions opportunistically, joining an ongoing dyadic contest to target an opponent without facing the possible risks of dyadic contest, such as a greater chance of injury.  相似文献   
980.
Thaumatin‐like proteins (TLPs) share structural similarity with the sweet‐tasting thaumatin protein but exhibit antifungal activity by inhibiting growth of fungal pathogens. In a Tenebrio model, two TLP genes were identified by RNA‐sequencing analysis and genome sequencing. Both TmTLP1 and TmTLP2 genes contain 729 nucleotide sequences encoding 242 amino acid residues, including an initiation codon (ATG) and a termination codon (TAA). Interestingly, TmTLPs are proteins with 14 central cysteine residues that may have an important role in structure formation. These data will be used to characterize the innate immune functions of TmTLPs in Tenebrio molitor.  相似文献   
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