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91.
IntroductionRapid and accurate pathogen identification is essential for the treatment of pneumonia. Metagenomic next‐generation sequencing (mNGS) is a newly developed technology to obtain microbial nucleic acid sequence information quickly, efficiently, and without bias.MethodsWe performed shotgun metagenomic next‐generation sequencing (mNGS) of bronchoalveolar lavage fluid (BALF) for pathogen identification in pneumonia in a prospective study with 138 patients from a single center. We compared the results of mNGS with standard methods including culture, staining, and targeted PCR and evaluated the clinical applicability of mNGS.ResultsMost of the patients (128/138, 92.75%) were cured or improved. One patient (1/138, 0.72%) died because of acute gastrointestinal bleeding, and 9 patients (9/138, 6.52%) showed no improvement. mNGS identified more bacteria (53 versus 27), fewer fungi (8 versus 31), and more viruses (16 versus 1) than standard methods. In total, treatment in 34 out of 138 cases (24.64%) was adjusted and optimized because of mNGS results. Positive mNGS results contributed to a definitive diagnosis in 23 cases (16.67%), which helped guide treatment decision by either adjusting the antibiotics without de‐escalation or continuing the empirical treatment. mNGS also confirmed no active infection in 11 cases (7.97%) allowed for antibiotic de‐escalation.ConclusionThis prospective clinical study evaluated the clinical utility of mNGS for the diagnosis of pneumonia and showed that mNGS of BALF provides valuable information for effective treatment.  相似文献   
92.
Surface treatment is known as a very efficient measure by which to modulate the surface properties of biomaterials in terms of grain structure, topography, roughness and chemistry to determine the osseointegration of implants. In this work, a two-step method of surface modification was employed to impart high osteogenic activity and biomineralization capacity on a Ti–25Nb–3Mo–2Sn–3Zr alloy (a type of β-titanium named TLM). The preliminary surface mechanical attrition treatment (SMAT) refined the average grain size from 170 ± 19 μm to 74 ± 8 nm in the TLM surface layer and promoted the surface to be much rougher and more hydrophilic. The subsequent Ca-ion implantation did not change the surface roughness and topography obviously, but enhanced the surface wettability of the SMAT-treated TLM alloy. The in vitro evaluations of the adhesion, proliferation, osteogenic genes (RUNX2, ALP, BMP-2, OPN, OCN and COL-I) and protein (ALP, OPN, OCN and COL-I) expressions, as well as extracellular matrix (ECM) mineralization of mesenchymal stem cells (MSCs) revealed that the initial SMAT-treated sample significantly enhanced the adhesion and osteogenic functions of MSCs compared to an untreated TLM sample, and the subsequent introduction of Ca ions onto the SMAT-derived nanograined sample further promotes the MSC adhesion, proliferation, osteo-differentiation and ECM mineralization due to the adsorption of more proteins such as laminin (Ln), fibronectin (Fn) and vitronectin (Vn) on the surface, as well as the increase in extracellular Ca concentrations. In addition, the biomineralization capacity of the samples was also evaluated by soaking them in simulated bodily fluid (SBF) at 37 °C for 28 days, and the results showed that the Ca-ion implanted sample significantly boosted the deposition of Ca and P containing minerals on its surface, which was associated with the generation of more Ti–OH groups on the surface after ion implantation. The combination of the SMAT technique and Ca-ion implantation thus endowed the TLM alloy with outstanding osteogenic and biomineralization properties, providing a potential means for its future use in the orthopedic field.

Combination of the SMAT technique and Ca-ion implantation produced a β-titanium alloy with a bioactive surface layer, which was proved to effectively promote the osteogenic activity of MSCs and Ca–P mineral deposition in vitro.  相似文献   
93.
目的 研究链霉菌多糖(SMP)对正常小鼠和免疫抑制模型小鼠的免疫调节活性.方法 通过混合淋巴细胞培养方法检测SMP对正常小鼠脾脏淋巴细胞增殖作用的影响,用酸性α-醋酸萘酯酶染色法观察免疫抑制小鼠模型外周血中T淋巴细胞的变化,以及流式细胞仪检测免疫抑制模型小鼠脾细胞中T细胞亚群Lyt2 和L3T4 的比例变化.结果 SMP可以明显促进混合淋巴细胞的增殖,并对免疫抑制模型小鼠T淋巴细胞的抑制有保护作用,还可以调节模型小鼠CD4 /CD8 的比值至正常水平.结论 SMP具有调节免疫功能的作用.  相似文献   
94.
目的 研究分析采用超声在遵循加速康复外科(ERAS)策略下监测高龄患者胃排空情况及预防反流误吸的临床疗效。方法 选取2020年7月至12月江门市五邑中医院及开平市中医院收治的60例拟择期行上腹部手术的高龄患者作为研究对象,按照随机数字表法分为对照组(30例)与试验组(30例),对照组于术前晚22∶00后要求患者一直保持禁饮禁食,试验组于术前2 h给予患者400 ml碳水化合物口服。两组患者进入麻醉准备间后,予超声监测患者胃排空情况和评估反流误吸风险。比较两组的右侧卧位的胃容量、胃窦横截面积、胃容积体重比、反流误吸风险。结果 两组患者的胃容量、胃窦横截面积、胃容积体重比、反流误吸风险比较,差异无统计学意义(P>0.05)。结论 高龄患者遵循ERAS策略可利用超声监测胃排空情况及预防反流误吸。  相似文献   
95.
Pseudorabies virus (PRV), the causative agent of Aujeszky’s disease, is one of the most important infectious pathogens threatening the global pig industry. Like other members of alphaherpesviruses, PRV establishes a lifelong latent infection and occasionally reactivates from latency after stress stimulus in infected pigs. Latent infected pigs can then serve as the source of recurrent infection, which is one of the difficulties for PRV eradication. Virus latency refers to the retention of viral complete genomes without production of infectious progeny virus; however, following stress stimulus, the virus can be reactivated into lytic infection, which is known as the latency-reactivation cycle. Recently, several research have indicated that alphaherpesvirus latency and reactivation is regulated by a complex interplay between virus, neurons, and the immune system. However, with those limited reports, the relevant advances in PRV latency are lagging behind. Therefore, in this review we focus on the regulatory mechanisms in PRV latency via summarizing the progress of PRV itself and that of other alphaherpesviruses, which will improve our understanding in the underlying mechanism of PRV latency and help design novel therapeutic strategies to control PRV latency.  相似文献   
96.
The very high cycle fatigue (VHCF) failure of in-service components is mainly caused by the vibration of thin-wall elements at a high frequency. In this work, a novel model of ultrasonic fatigue test was developed to test thin-wall material in bending up to VHCF with an accelerated frequency. The theoretical principle and finite element analysis were introduced for designing a sample that resonated at the frequency of 20 kHz in flexural vibration. In the advantage of the second-order flexural vibration, the gauge section of the sample was in the pure bending condition which prevented the intricate stress condition for thin-wall material as in the root of cantilever or the contact point of three points bending. Moreover, combining the constraint and the loading contact in one small section significantly reduced heating that originated from the friction at an ultrasonic frequency. Both strain gauge and deflection angle methods were applied to verify the controlling of stress amplitude. The fractography observation on Ti6Al4V samples indicated that the characterized fracture obtained from the novel model was the same as that from the conventional bending test.  相似文献   
97.
目的了解该院药品不良反应(ADR)发生特点,促进临床合理用药。方法对该院2010年1月-2011年7月收集到的186例ADR报告进行回顾性分析。结果发生ADR的186例患者中,以≥40岁者最多;药物种类以抗生素、注射用中成药为主;给药途径以静脉给药为主;发生ADR频率最高的是氨苄西林钠克拉维酸钾;所涉及的器官/系统中以皮肤及其附件为主。结论应加强ADR监测和ADR知识的宣传,以减少和避免其发生。  相似文献   
98.
目的评价Proviewer一次性使用软组织阻隔装置在颅内手术操作过程中的有效性和安全性,为推广应用提供科学依据。方法采用前瞻性随机对照的临床研究方法,以应用Proviewer一次性使用软组织阻隔装置为试验组,以传统脑压板手术为对照,比较两组手术间临床疗效及手术安全性的差异。结果从2011年06月至2011年12月,共有19例患者纳入全分析集(FAS),其中试验组10例,对照组9例。因为年龄违反入选标准而排除2例,故符合方案集(PPS)共有17例,其中试验组9例,对照组8例。纳入安全性分析集的19例,其中试验组10例,对照组9例。以临床效果综合计分作为主要疗效指标。试验组和对照组比较,在FAS和PPS的差异均具有统计学意义(P<0.05),试验组优于对照组。进一步对视野观察计分和主述性观察计分指标进行比较,表现出相同的结果,即在FAS和PPS的差异均具有统计学意义(P<0.05),试验组优于对照组。以不良事件作为安全性评价指标。试验组共出现1人(10.00%),对照组共出现1人(11.11%)。两组不良事件发生率差别无统计学意义(P>0.05)。所有不良事件均与治疗器械无关,且在病人出院前消除。结论Proviewer一次性使用软组织阻隔装置与传统脑压板相比,在颅内手术操作过程中能为手术者提供更好的观察视野、便利的手术操作,减少术中出血量;且未产生与医疗器械有关的不良反应,有较高的临床应用价值,值得临床推广使用。  相似文献   
99.
目的:建立测定人血浆中苯海拉明血药浓度的方法,并进行其生物等效性研究。方法:血样经处理后,采用高效液相色谱串联质谱电喷雾(LC-MS/MS)法进样测定。色谱柱为Intersil Hilic(150mm×3.0mm,5μm),流动相为乙腈-水(10mmol/L乙酸铵)-甲酸(40:60:1,V/V/V);电喷雾电离(ESI)离子源,正离子模式,多级反应监测(MRM)方式检测,离子对分别为m/z256→167(苯海拉明)、m/z344→215(氯马斯汀,内标)。结果:苯海拉明血药浓度在0.5~125ng/ml范围内线性关系良好(r=0.9965);日内、日间RSD均<8%,方法回收率为99.4%~103.4%,提取回收率为71.9%~75.3%。受试者口服氨麻苯美片受试制剂与参比制剂后苯海拉明的主要药动学参数分别为:t1/2(9.892±1.615)、(10.745±3.227)h,tmax(2.00±0.81)、(1.78±0.55)h,cmax(90.4±20.6)、(103.0±30.1)h,AUC0-36h(806.293±211.453)、(827.856±223.996)h。结论:本方法灵敏、准确,适用于苯海拉明血药浓度测定及其生物利用度研究;2种制剂生物等效。  相似文献   
100.
目的探讨青光眼复合小梁切除术与单纯小梁切除术后前房形成延缓的原因和对策。方法实验组30眼行复合小梁切除术,对照组28眼行单纯小梁切除术,比较两组术后眼压及前房形成延缓的情况。结果两组术后眼压控制差异无显著性,但实验组术后浅前房的发生率明显低于对照组,差异有显著性垆〈0.05)。结论复合小梁切除术控制前房形成延缓优势明显。  相似文献   
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