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异质性耐药是一种特殊的细菌耐药类型,常表现为同一克隆来源的不同细菌亚群对某种抗菌药物表现出不一致的耐药特征,大多数亚群对某种抗菌药物敏感,而少部分亚群对其耐药或高度耐药。异质性耐药分离株常会导致特定抗菌药物抗感染治疗失败。针对异质性耐药菌较为深入的研究主要集中于革兰阴性菌,革兰阳性球菌的相关报道较少。近年有研究报道万古霉素、利奈唑胺、苯唑西林等多种类型抗菌药物异质性耐药金黄色葡萄球菌分离株出现,但其实际临床意义尚待进一步评估。此文对金黄色葡萄球菌异质性耐药机制和检测技术最新进展进行综述,为细菌异质性耐药机制研究和新型检测技术研发提供新的思路。 相似文献
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《Seminars in perinatology》2022,46(7):151635
The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) maintains a database of extremely preterm infants known as the Generic Database (GDB). Begun in 1987, this database now includes more than 91,000 infants, most of whom are extremely preterm (<29 weeks gestation). The GDB has been the backbone of the NRN, providing high quality, prospectively collected data to study the changing epidemiology of extreme prematurity and its outcomes over time. In addition, GDB data have been used to generate hypotheses for prospective studies and to develop new clinical trials by providing information about the numbers and characteristics of available subjects and the expected event rates for conditions and complications to be studied. Since its inception, the GDB has been the basis of more than 200 publications in peer-reviewed journals, many of which have had a significant impact on the field of neonatology. 相似文献
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《Drug discovery today》2022,27(5):1367-1380
The tremendous advances in genomics, recombinant DNA technology, bioengineering and nanotechnology, in conjunction with the development of high-end computations, have been instrumental in the process of rational design of peptide-based vaccines. The use of peptide vaccines was limited owing to their inherent instability when systemically administered; however, advanced formulation techniques have been developed for their systemic delivery, thereby overcoming their degradation, clearance, cellular uptake and off-target effects. With the rise of sophisticated immunological predictors and experimental techniques, several methodological advances have occurred in this field. This review examines contemporary methods to identify and optimize epitopes, engineer their immunogenic properties and develop their safe and efficient delivery into the host. 相似文献
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《Archivos de bronconeumología》2022,58(5):406-411
IntroductionLung cancer (LC) is usually diagnosed at advanced stages with only a 12% 5-year survival. Trials as NLST and NELSON show a mortality decrease, which justifies implementation of lung cancer screening in risk population. Our objective was to show survival results of the largest LC screening program in Spain with low dosage computed tomography (LDCT).MethodsClinical records from International Early Lung Cancer Detection Program (IELCAP) at Valencia, Spain were analysed. This program recruited volunteers, ever-smokers aged 40-80 years, since 2008. Results are compared to those from other similar sizeable programs.ResultsA total of 8278 participants were screened with at least two-rounds until November 2020. A mean of 6 annual screening rounds were performed. We detected 239 tumours along 12-year follow-up. Adenocarcinoma was the most common histology, being 61.3% at stage I. The lung cancer prevalence and incidence proportion was 1.5% and 1.4%, respectively with an annual detection rate of 0.17. One-year survival and 10-year survival were 90% and 80.1%, respectively. Adherence was 96.84%.ConclusionLargest lung cancer screening in Spain shows that survival is improved when is performed in multidisciplinary team experienced in management of LC, and is comparable to similar screening programs. 相似文献
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背景 结核病是导致人免疫缺陷病毒/获得性免疫缺陷综合征(HIV/AIDS)患者死亡的首要原因,而HIV感染也是导致结核潜伏感染(LTBI)发展为结核病的主要危险因素。因此,对HIV/AIDS患者进行LTBI筛查和治疗是预防该类人群结核病的发生从而减少其死亡的重要举措。 目的 对宁夏回族自治区银川市市区内HIV/AIDS患者进行LTBI筛查,并分析其影响因素,识别高危人群,为HIV/AIDS患者结核病的预防性治疗提供科学依据。 方法 选取2021年3—8月于宁夏回族自治区银川市市区内定点管理单位治疗的546例HIV/AIDS患者为研究对象。通过现场问卷调查及查阅患者管理档案的方式收集HIV/AIDS患者的一般资料,其中一般人口学特征包括性别、年龄、民族、学历、婚姻状况、家庭人均年收入、职业类型、体质指数(BMI)、吸烟情况、饮酒情况等;临床资料包括慢性病患病情况、与结核病患者密切接触情况、HIV/AIDS确诊时长、抗病毒治疗时长、合并其他感染情况、近期CD4+ T淋巴细胞计数(CD4)等。通过结核菌素皮肤试验(TST)对研究对象进行LTBI筛查,根据TST结果将546例HIV/AIDS患者分为非LTBI组(TST阴性413例)和LTBI组(TST阳性133例)。比较两组患者的一般资料,采用多因素Logistic回归分析探讨HIV/AIDS患者发生LTBI的影响因素,并利用R软件建立限制性立方样条模型拟合CD4与LTBI风险之间的量效关系。 结果 银川市市区内HIV/AIDS患者的TST阳性率为24.4%。已婚〔OR=0.544,95%CI(0.321,0.922),P<0.05〕是HIV/AIDS患者发生LTBI的保护因素;吸烟〔OR=1.919,95%CI(1.213,3.037),P<0.05〕、与结核病患者有过密切接触〔OR=11.100,95%CI(2.889,42.648),P<0.05〕是HIV/AIDS患者发生LTBI的危险因素。限制性立方样条模型拟合结果显示,HIV/AIDS患者的CD4与LTBI风险呈近似"n"形的非线性关系(非线性检验χ2=29.080,P<0.001)。 结论 应重点关注HIV/AIDS患者中未婚、吸烟、与结核病患者有过密切接触人群LTBI的发生情况,并及时进行预防性治疗;对于CD4较低的患者,建议采用多种方法进行LTBI筛查。 相似文献
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Analytical procedure for detection and quantification of etaqualone in human blood and urine using GC–MS/MS was established and applied to authentic human samples obtained from volunteers. A liquid–liquid extraction method was employed. Each 1.0 mL of blood or urine was alkalized and extracted with diethyl ether. The solvent layer was evaporated to dryness and reconstituted with methanol then analyzed by GC–MS/MS. linear relationships within the concentration range of 1–100 ng/mL were obtained in calibrators for both blood and urine, demonstrating correlation coefficients values being>0.999. For blood and urine samples, the intra-day assay precision and accuracy values are each less than 3.65%, 7.13%, and 6.02%, 9.12%; those values of the inter-day assay are each less than 1.82%, 6.74%, and 3.99%, 7.41%. The extraction recovery rates for etaqualone ranged from 98.7% to 106%. The lower limit of quantifications was 1.0 ng/mL in both blood and urine. Stabilities of etaqualone in blood and urine were satisfactory under various temperatures within 15 days. 8.51 and 2.06 ng/mL of etaqualone in blood and urine were detected at 4 h later oral ingestion; 6.91 and 3.94 ng/mL of etaqualone were also detected 30 min and 2 h later smoking from blood and urine. 相似文献