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1.
《Research in microbiology》2022,173(3):103901
Infections caused by Klebsiella pneumoniae are often difficult to manage due to the high frequency of multidrug resistance, often conferred by efflux pumps. In this study, we analyzed sequence variations of the major RND family multidrug efflux pump AcrB from 387 assembled K. pneumoniae genomes. We confirm that AcrB is a highly-conserved efflux pump in K. pneumoniae, and identified several variants that were prevalent in clinical isolates. Molecular dynamics analyses on two of these variants (L118M and S966A) suggested conformational changes that may correlate with increased drug efflux capabilities. The L118M change resulted in enhanced protein rigidity while the flexibility of drug binding pockets was stable or increased, and the interactions between the proximal pockets and water molecules were stronger. For S966A, the significantly enlarged proximal pocket suggested higher drug accommodation ability. Consistent with these predictions, the L118M and S966A variants conferred a slightly increased ability to grow in the presence of tetracycline and to survive cefoxitin exposure when overexpressed. In summary, our results suggest that the emergence of enhanced-function AcrB variants may be a potential risk for increased antibiotic resistance in clinical K. pneumoniae isolates.  相似文献   
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目的探讨行机械通气治疗患儿在撤机后序贯维持镇痛镇静药物对预防谵妄及撤药反应的效果。方法回顾性将2019年12月至2021年9月广东医科大学附属东莞市儿童医院儿童重症监护室收治的机械通气支持≥5 d的61例患儿分为对照组(30例,撤机后无镇痛镇静药物维持)及观察组(31例,撤机后序贯镇痛镇静药物维持48 h),记录两组患儿撤机后24 h及72 h索菲亚撤药反应观察量表(Sophia Observation Withdrawal Symptoms Scale,SOS)评分、儿童谵妄量表(Paediatric Delirium Scale,PD)评分、Richmond躁动镇静量表(Richmond Agitation-Sedation Scale,RASS)评分及谵妄发生例数、撤药反应发生例数,并进行比较分析。结果两组患儿撤机后24 h及72 h谵妄发生率比较差异无统计学意义(P>0.05);观察组撤机后24 h及72 h撤药反应发生率、SOS评分、PD评分、RASS评分均低于对照组(P<0.01)。结论撤机后序贯镇痛镇静可降低行机械通气治疗重症患儿撤机后72 h内撤药反应发生率,但不能有效降低患儿撤机后谵妄发生率。  相似文献   
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目的 探讨瞬时脉冲足底静脉泵预防全髋/膝关节置换术后深静脉血栓形成(DVT)的效果,为临床医护人员选择最优的机械预防方式提供参考依据。方法 选取2019年11月至2020年8月在我院关节外科拟行全髋/膝关节置换术的病人210例,随机分为观察组(105例)和对照组(105例);术后,观察组和对照组分别使用瞬时脉冲足底静脉泵和间歇性充气加压装置预防DVT。观察比较两组病人术后DVT的发生率、术后D-二聚体、C-反应蛋白、白细胞介素-6和患肢肿胀情况,住院时间和使用机械设备预防DVT的舒适度。结果 术后2周,观察组DVT总发生率为6.67%,对照组为9.52%,两组比较,差异无统计学意义(P>0.05);观察组病人机械设备使用的舒适度高于对照组,差异有统计学意义(P<0.05)。结论 瞬时脉冲足底静脉泵可有效预防全髋/膝关节置换术后DVT,且舒适度高于间歇充气加压装置,预防DVT的时间成本低,值得临床推广。  相似文献   
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摘要:抗生素滥用已导致全球范围内的抗生素耐药危机,人们不得不开始寻求新的策略解决这一问题。古老的噬菌体疗法 因噬菌体杀菌效力强、可自我复制等优势而重新受到重视。但单独使用噬菌体可能面临一系列问题,如抗菌谱过窄,噬菌体抗 性及免疫原性等。噬菌体与抗生素联合应用能够协同裂解宿主细菌,更好地控制或根除细菌感染,因此,二者联用在近年来开 始成为噬菌体疗法的研究和应用热点。本文通过整理噬菌体与抗生素联合应用的研究文献及临床报道,探讨、总结噬菌体与抗 生素的协同作用机制,以期进一步推动噬菌体与抗生素联合的研究与应用。  相似文献   
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Introduction and objectivesThis study aimed to assess the safety and efficacy of midazolam and ketamine as adjuvants to the peribulbar block in vitreoretinal surgeries.Patients and methodsThis randomized controlled trial included 93 adult patients undergoing vitreoretinal surgeries performed with peribulbar anaesthesia. Patients were randomly allocated to 3 groups (31 participants each): control (standard anaesthetic mixture), midazolam (standard mixture + midazolam), and ketamine (standard mixture + ketamine). The primary outcomes were onset of globe akinesia and duration of analgesia. Secondary outcomes were duration of motor blockade, onset of corneal anaesthesia and lid akinesia, and changes in vital data (blood pressure, oxygen saturation, and pulse rate).ResultsThe ketamine group vs. the control and midazolam groups showed the most rapid onset of lid and globe akinesia (p < 0.001) and corneal anaesthesia (0.7 ± 0.2 vs. 1.5 ± 0.5 and 1.2 ± 0.4, respectively; p < 0.001) and the longest duration of both analgesia (3.7 ± 0.6 vs. 2.3 ± 0.4 and 3.1 ± 0.6, respectively; p < 0.001) and akinesia (3.8 ± 0.5 vs. 3.0 ± 0.4, and 3.7 ± 0.5, respectively; p < 0.001). The midazolam group showed better outcomes than controls, but the drug was less effective than ketamine. There were no significant differences in vital data among groups (p > 0.05).ConclusionsKetamine is an effective adjuvant for peribulbar blockade. It enhances both motor and sensory blockade by hastening onset and prolonging duration. These effects are desirable in lengthier ophthalmic procedures such as vitreoretinal surgeries. The effects of ketamine were superior to those of midazolam.  相似文献   
7.
《Injury》2023,54(7):110761
ObjectivesHistorically, pelvic ring fractures (PRF) are considered to occur predominantly in the anterior ring and therfore to be mechanically stable. Combined anterior and posterior (A + P) PRF are expected to be less mechanically stable and therefore to be associated with higher levels of pain and reduced mobility compared to isolated anterior fractures. The current study investigates the clinical relevance of combined A + P PRF in elderly patients.MethodsA prospective multicentre cohort study was conducted in patients >70 years of age with anterior PRF after low-energy trauma diagnosed on conventional radiographs. All patients underwent an additional CT-scan. Patients were divided into two groups; isolated anterior or combined A + P fractures. Patients were treated conservatively with adequate analgesia for at least one week. If patients could not be mobilised after conservative treatment, surgical fixation was performed. Numerical Rating Scale (NRS) pain scores, dependence on walking aids and Activities of Daily Living scores (ADL) were measured at 2–4 weeks, and 3, 6 and 12 months after fracture.Results102 patients (age 81.1 ± 7.6 years) were included. Isolated anterior fractures were diagnosed in 25 (24.5%) and A + P fractures in 77 (75.5%) patients. Baseline characteristics did not differ between the two groups. Most patients were successfully treated conservatively and 5 (4.9%) underwent percutaneous trans-iliac, trans-sacral screw fixation after failure of conservative treatment. At 2–4 weeks post trauma, patients with A + P fractures had similar median pain scores (3 (range 0–8) vs. 5 (0–10), p = 0.19) and ADL scores (85 (25–100) vs. 78.6 (5–100), p = 0.67), but were more dependent on walking aids (92.8% vs. 72.2%; p = 0.02) compared to patients with isolated anterior fractures. There were no significant differences at 3 months. At one year follow-up the median NRS pain and ADL scores for both fracture groups were 0 and 100, respectively. Mortality was 10.8%, and additional loss to follow-up was 17.6%.ConclusionsThe vast majority of elderly patients with PRF have combined A + P fractures. The clinical implications of additional posterior pelvic ring fractures in elderly patients appears to be limited.  相似文献   
8.
Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  相似文献   
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Proton pump inhibitors (PPIs), the most commonly used antisecretory medi-cations in the management of reflux illness, virtually eliminate elective surgery for ulcer disease, and relegate anti-reflux surgery to patients with gastroesophageal reflux disease (GERD) who are inadequately managed by medical therapy. However, PPI medications still leave some therapeutic demands of GERD unmet. Furthermore, up to 40%-55% of daily PPI users have chronic symptoms, due to PPI refractoriness. Potassium-competitive acid blockers (P-CABs) transcend many of the problems and limits of PPIs, delivering quick, powerful, and extended acid suppression and allowing for treatment of numerous unmet needs. Recently, it has become clear that compromised mucosal integrity plays a role in the etiology of GERD. As a result, esophageal mucosal protection has emerged as a novel and potential treatment approach. An increasing body of research demonstrates that when P-CABs are used as primary drugs or add-on drugs (to regular treatment), they provide a considerable extra benefit, particularly in alleviating symptoms that do not respond to PPI therapy.  相似文献   
10.
目的研究硝酸甘油泵入治疗视网膜中央动脉阻塞(CRAO)的有效性。方法32例(32眼)确诊为视网膜中央动脉阻塞患者,随机分为微泵组及对照组,每组16例(16眼)。对照组患者给予舌下含服硝酸甘油片联合常规治疗,微泵组患者给予静脉泵入硝酸甘油联合常规治疗。比较两组患者治疗后最佳矫正视力、视网膜水肿发生情况及治疗前后臂-视网膜循环时间。结果治疗后,微泵组患者最佳矫正视力为(0.35±0.11),对照组患者最佳矫正视力为(0.16±0.07),微泵组患者治疗后最佳矫正视力优于对照组,差异具有统计学意义(P<0.05)。治疗后,微泵组患者的视网膜水肿发生率为31.25%(5/16),明显低于对照组的68.75%(11/16),差异具有统计学意义(P<0.05)。微泵组患者治疗前臂-视网膜循环时间为(38.7±2.4)s,治疗1周后臂-视网膜循环时间为(20.4±2.3)s;对照组患者治疗前臂-视网膜循环时间为(36.9±3.5)s,治疗1周后臂-视网膜循环时间为(29.3±3.1)s;两组患者治疗前臂-视网膜循环时间比较,差异无统计学意义(P>0.05);治疗1周后,两组患者的臂-视网膜循环时间均短于治疗前,且微泵组短于对照组,差异具有统计学意义(P<0.05)。结论硝酸甘油泵入治疗视网膜中央动脉阻塞效果显著,可有提高患者的视力,促进视网膜血液循环的恢复。  相似文献   
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