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81.
摘要 目的:研究重症监护室(ICU)呼吸机相关性肺炎(VAP)患者病原菌分布及中性粒细胞与淋巴细胞计数比值(NLR)、血清磷、降钙素原(PCT)联合检测对死亡风险的预测价值。方法:选取上海市第一人民医院于2020年1月~2022年1月收治的60例VAP患者。采集所有患者呼吸道分泌物并进行细菌培养。此外,将其按照预后的不同分为死亡组21例以及存活组39例,比较两组NLR、血清磷及PCT水平。以单因素及多因素Logistic分析VAP患者死亡的危险因素,并通过受试者工作特征(ROC)曲线分析NLR、血清磷及PCT预测死亡的效能。结果:60例VAP患者呼吸道分泌物检出病原菌共82株,以革兰阴性菌占比最高,共检出革兰阴性菌75.61%、革兰阳性菌21.95%、真菌2.44%。按照占比从高到低的顺序分别为鲍氏不动杆菌20.73%,铜绿假单胞菌18.29%,肺炎克雷伯菌17.07%,金黄色葡萄球菌13.41%,大肠埃希菌12.20%,其他革兰阴性菌7.32%,表皮葡萄球菌4.88%,肠球菌属3.66%,真菌2.44%。死亡组NLR及PCT水平均高于存活组,而血清磷水平低于存活组(P<0.05)。单因素分析结果显示:急性生理与慢性健康评分(APACHEⅡ)评分及有创机械通气时间均和VAP患者死亡有关(P<0.05)。多因素Logistic回归分析显示:APACHEⅡ评分较高、有创机械通气时间较长与NLR、PCT水平较高均是VAP患者死亡危险因素,血清磷水平较高是VAP患者死亡的保护因素(P<0.05)。ROC曲线分析显示:NLR、血清磷及PCT联合预测VAP患者死亡的效能优于上述三项指标单独预测。结论:VAP患者主要病原菌为革兰阴性菌,临床应合理选用抗菌药物治疗,NLR、血清磷及PCT均和患者死亡有关,联合检测对死亡风险的预测价值较高。  相似文献   
82.
摘要 目的:探究血清淀粉样蛋白A(SAA)、几丁质酶样蛋白YKL-40和肺表面活性物质相关蛋白-A(SP-A)表达水平对的联合检测对小儿难治性肺炎支原体肺炎(RMPP)的预测价值。方法:纳入2019年11月至2021年12月期间我院收治的60例MPP患儿作为研究对象,依据病情最终转归将其分为RMPP组和普通肺炎支原体肺炎(GMPP)组,另纳入同期于我院行体格检查的60例健康儿童作为对照组。收集所有受试儿童的临床资料、实验室指标及影像学结果,采用酶联免疫吸附法(ELISA)检测血清SAA、YKL-40和SP-A的表达水平,应用受试者工作特征曲线(ROC)判定各指标单项检测和联合检测的预测效能。结果:MPP组患儿和对照组儿童一般资料相比无统计学差异(P>0.05)。依据病情最终转归,60例MPP患儿中共有23例(38.33 %)进展为RMPP,RMPP组与GMPP组患儿在白介素-6(IL-6)、C-反应蛋白(CRP)、降钙素原(PCT)、D-二聚体(D-D)等实验室指标以及肺不张、胸腔积液等影像学特征方面相比有统计学差异(P<0.05)。RMPP组和GMPP组血清SAA、YKL-40和SP-A的表达水平显著高于对照组(P<0.05),同时RMPP组血清SAA、YKL-40和SP-A的表达水平显著高于GMPP组(P<0.05)。血清SAA的最佳截断值为39.75 mg/L,预测RMPP发生的ROC曲线下面积为0.894(95%CI:0.861-0.925),敏感度为78.26 %,特异度为86.67 %;血清YKL-40的最佳截断值为31.85 ng/mL,预测RMPP发生的ROC曲线下面积为0.754(95%CI:0.634-0.873),敏感度为73.91 %,特异度为67.21 %;血清SP-A的最佳截断值为35.59 ng/mL,预测RMPP发生的ROC曲线下面积为0.761(95%CI:0.640-0.891),敏感度为73.91 %,特异度为75.00 %;SAA+YKL-40-1+SP-A三者联合检测预测RMPP的AUC为0.914(95%CI:0.871-0.957),敏感度为91.30 %,特异度为91.66 %。结论:血清SAA、YKL-40和SP-A表达水平的检测可作为预测RMPP发生的重要生物学指标,且三者联合检测的预测效能较高,可为临床尽早诊断RMPP、尽早干预、改善患儿预后提供一定的帮助。  相似文献   
83.
摘要 目的:探讨血清肿瘤标志物与宫颈癌病理特征的关系及对术后复发的预测研究。方法:选择2015年1月至2017年12月来我院诊治的宫颈癌患者82例作为观察组,选择同期来我院体检的健康女性者50例,两组均使用电化学发光免疫分析法检测血清中的CA125、CA153、CA199、CEA水平,观察组患者随访时间截至2022年12月。对比两组血清CA125、CA153、CA199、CEA水平,分析观察组患者血清CA125、CA153、CA199、CEA水平与临床病理特征的关系,分析观察组患者术后随访复发情况,宫颈癌根治术后患者复发的单因素与多因素Cox回归结果,血清CA125、CA153、CA199、CEA水平对宫颈癌根治术后复发的预测价值。结果:观察组的血清CA125、CA153、CA199、CEA水平明显较对照组高(P<0.05)。宫颈癌患者不同FIGO分期、间质浸润深度及是否存在淋巴结转移间血清CA125、CA153、CA199、CEA水平对比有统计学意义(P<0.05)。82例患者随访时间为13~60个月,中位生存时间为39个月,截止2022年12月末次随访,82例患者术后复发18例(21.95%)。单因素及多因素Cox回归分析表明,FIGO分期在ⅡA期、间质浸润深度≥1/2、有淋巴结转移、CA125≥307.41 U/mL、CA153≥185.89 U/mL、CA199≥153.23 U/mL、CEA≥30.15 ng/mL是影响宫颈癌术后复发的独立危险因素。ROC曲线显示,CA125+CA153+CA199+CEA预测宫颈癌术后复发的AUC明显较CA125、CA153、CA199、CEA单独指标预测价值高(P<0.05)。结论:宫颈癌患者血清CA125、CA153、CA199、CEA高表达,其与间质浸润深度、FIGO 分期、淋巴结转移、术后复发有关,四者联合可作为宫颈癌术后复发的预测指标。  相似文献   
84.
Adults of Cacopsylla melanoneura, vector of the apple proliferation (AP) phytoplasma, were collected every 2 weeks from January until May in 2000 and 2001 by the beating tray method in eight apple orchards of the Aosta Valley (northwestern Italy). Total DNA was extracted from batches of five insects and amplified with the universal phytoplasma primers P1/P7 in direct PCR. A nested PCR assay was then performed on P1/P7 amplicons using the primers fO1/rO1, specific for the AP‐ phytoplasma group. The digestion of fO1/rO1 amplicons with Ssp I restriction endonuclease confirmed that C. melanoneura adults harboured the AP phytoplasma. The data obtained with PCR were used to estimate the proportion of AP‐positive insects in over wintered and offspring adults. Percentages of AP‐positive insects of 3.6% and 0.8% were estimated in 2000 among over wintered and offspring psyllids respectively. In 2001 only the over wintered insects were found infected, with an estimated proportion of 2.8%. The seasonal abundance of the vector was measured using yellow sticky traps. C. melanoneura was always present at a low population level, and the highest density was recorded from mid‐February until mid‐March in both years. The results show that the overwintered population is higher and spends a longer period in apple orchards, suggesting the crucial role of the overwintered adults in vectoring AP.  相似文献   
85.
细菌巨大质粒的快速检测   总被引:3,自引:0,他引:3  
本文报道了一种快速检测微生物巨大质粒的方法.该方法是通过对Eckhardt所报道的方法加以改进,使之能对根瘤菌、大肠杆菌、甚至链霉菌的大质粒进行快速检测.  相似文献   
86.
Oligozymes     
The simple use of nonisotopic hybridization probes to detect complementary sequences provides valuable information in a large number of research and commercial applications. In hybridization assays, the four ‘S’s (speed, simplicity, sensitivity, and specificity) are important criteria for determining the choice of probe and label. The direct chemical combination of synthetic oligonucleotide probes and enzyme labels offer advantages unmatched by other approaches, with the oligonucleotide providing rapid hybridization and high specificity, and the direct enzyme label providing simple and sensitive detection. Such oligonucleotide-enzyme conjugates (“oligozymes”) can be used in a variety of hybridization and detection formats, including dot blots, Southern/northern blots,in situ, and solution hybridization/capture schemes. The practical synthesis and use of such oligozymes are summarized.  相似文献   
87.
The nuclear ribosomal DNA of the entomopathogenic fungus Beauveria brongniartii is polymorphic in terms of both restriction site and length. Insertions of 350–450 bp long, identified as group-I introns, were detected in the 28 s rDNA. A panel of 47 strains of B. brongniartii , two B. bassiana and one Metarhizium anisopliae of various geographical and biological origins were found to contain 14 variant forms of intron differing in size and restriction pattern, at four different positions. Twelve types of ribosomal large subunit were defined on the basis of variant distribution and compared with strain clustering based on internal transcribed spacers analysis. There was a correlation between the characteristic introns and isolates collected from the sugar cane pest Hoplochelus marginalis . Primers for polymerase chain reaction amplification were chosen from these variants, and used to develop a specific method for detecting strains pathogenic towards Hoplochelus .  相似文献   
88.
A systematic study of the membrane-associated regions in the plasma membrane Ca2+ pump of erythrocytes has been performed by hydrophobic photolabeling. Purified Ca2+ pump was labeled with 3-(trifluoromethyl)-3-(m-[125I]iodophenyl)-diazirine ([125I]TID), a generic photoactivatable hydrophobic probe. These results were compared with the enzyme labeled with a strictly membrane-bound probe, [3H]bis-phosphatidylethanolamine (trifluoromethyl) phenyldiazirine. A significant light-dependent labeling of an M(r) 135,000-140,000 peptide, corresponding to the full Ca2+ pump, was observed with both probes. After proteolysis of the pump labeled with each probe and isolation of fragments by SDS-PAGE, a common pattern of labeled peptides was observed. Similarly, labeling of the Ca2+ pump with [125I]TID, either in isolated red blood cell membranes or after the enzyme was purified, yields a similar pattern of labeled peptides. Taken together, these results validate the use of either probe to study the lipid interface of the membrane-embedded region of this protein, and sustain the notion that the conformation of the pump is maintained throughout the procedures of solubilization, affinity purification, and reconstitution into proteoliposomes. In this work, we put special emphasis on a detailed analysis of the N-terminal domain of the Ca2+ pump. A labeled peptide of M(r) 40,000 belonging to this region was purified and further digested with V8 protease. The specific incorporation of [125I]TID to proteolytic fragments pertaining to the amino-terminal region indicates the existence of two transmembrane stretches in this domain. A theoretical analysis based on the amino acid sequence 1-322 predicts two segments with high probability of membrane insertion, in agreement with the experimental data. Each segment shows a periodicity pattern of hydrophobicity and variability compatible with alpha-helical structure. These results strongly suggest the existence of a transmembrane helical hairpin motif near the N-terminus of the Ca2+ pump.  相似文献   
89.
鼠脑微透析液痕量氨基酸的激光诱导荧光检测   总被引:3,自引:0,他引:3  
使用自制微透析探针和活动体位生化取样装置以及自行组装的毛细管电泳-增强型电荷耦合器件-激光诱导荧光系统,对鼠脑透析液中的痕量氨基酸以异硫氢酸荧光黄(FITC)进行柱前衍生后进行了分离和检测. 鼠脑海马CA3区微透析液中游离氨基酸的浓度为10-8~10-6 mol/L, 并将其用于学习与记忆的研究, 为无损伤研究活体脑内神经递质和其他痕量生化物质的动态变化提供了一种新方法.  相似文献   
90.
Abstract: Oxygen radicals have been implicated in the neurodegenerative and other neurobiological effects evoked by methamphetamine (MA) in the brain. It has been reported that shortly after a single large subcutaneous dose of MA to the rat, the serotonergic neurotoxin 5,6-dihydroxytryptamine (5,6-DHT) is formed in the cortex and hippocampus. This somewhat controversial finding suggests that MA potentiates formation of the hydroxyl radical (HO?) that oxidizes 5-hydroxytryptamine (5-HT) to 5,6-DHT, which, in turn, mediates the degeneration of serotonergic terminals. A major and more stable product of the in vitro HO?-mediated oxidation of 5-HT is 5-hydroxy-3-ethylamino-2-oxindole (5-HEO). In this investigation, a method based on HPLC with electrochemical detection (HPLC-EC) has been developed that permits measurement of very low levels of 5-HEO in rat brain tissue in the presence of biogenic amine neurotransmitters/metabolites. After intracerebroventricular administration into rat brain, 5-HEO is transformed into a single major, but unknown, metabolite that can be detected by HPLC-EC. One hour after administration of MA (100 mg/kg s.c.) to the rat, massive decrements of 5-HT were observed in all regions of the brain examined (cortex, hippocampus, medulla and pons, midbrain, and striatum). However, 5-HEO, its unidentified metabolite, or 5,6-DHT were not detected as in vivo metabolites of 5-HT. MA administration, in particular to rats pretreated with pargyline, resulted in the formation of low levels of N-acetyl-5-hydroxytryptamine (NAc-5-HT) in all brain regions examined. These results suggest that MA does not potentiate the HO?-mediated oxidation of 5-HT. Furthermore, the rapid MA-induced decrease of 5-HT might not only be related to oxidative deactivation of tryptophan hydroxylase, as demonstrated by other investigators, but also to the inhibition of tetrahydrobiopterin biosynthesis by NAc-5-HT. The massive decrements of 5-HT evoked by MA are accompanied by small or no corresponding increases in 5-hydroxyindole-3-acetic acid (5-HIAA) levels. This is due, in part, to the relatively rapid clearance of 5-HIAA from the brain and monoamine oxidase (MAO) inhibition by MA. However, the loss of 5-HT without corresponding increases in its metabolites point to other mechanisms that might deplete the neurotransmitter, such as oxidation by superoxide radical anion (O2??), a reaction that in vitro does not generate 5-HEO or 5,6-DHT but rather another putative neurotoxin, tryptamine-4,5-dione. One hour after administration, MA evokes large depletions of norepinephrine (NE) throughout the brain but somewhat smaller decrements of dopamine (DA) that are restricted to the nigrostriatal pathway. Furthermore, MA evokes a major shift in the metabolism of both NE and DA from the pathway mediated by MAO to that mediated by catechol-O-methyltransferase. The profound and widespread effects of MA on the noradrenergic system, but more anatomically localized influence on the dopaminergic system, suggests that NE in addition to DA, or unusual metabolites of these neurotransmitters, might play roles in the neurodegenerative effects evoked by this drug.  相似文献   
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