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1.
目的评价不同消毒方法对清洁用具和地面洁净程度的影响。方法清洁用具分别采用化学消毒剂浸泡和机械热力消毒,用ATP拭子对消毒前后的清洁用具和病房地面采样,使用ATP荧光检测仪进行分析,比较不同消毒方法的效果。结果地面清洁消毒前拖把表面RLU值为137.00±20.98,地巾表面RLU值为1.20±0.84,地巾表面RLU值水平低于拖把表面,差异具有统计学意义(Z=-2.63,P<0.001)。清洁后拖把组地面平均RLU值减少24.78%,地巾组地面平均RLU值减少55.52%,差异具有统计学意义(Z=-6.03,P<0.001)。结论机械热力消毒处理的地巾比化学消毒剂浸泡的拖把洁净程度更高,采用机械热力消毒后的地巾清洁的地面也更干净。  相似文献   
2.
目的:探讨荧光免疫层析法(fluorescence immunochromatography assay,FICA)与酶联免疫吸附法(ELISA)检测英夫利西单抗(infliximab,IFX)血药浓度结果的相关性与一致性。方法:采用已上市的IFX药物浓度测定试剂盒(荧光免疫层析法)与实验室建立的检测IFX浓度的ELISA方法测定克罗恩病患者血液样本IFX浓度。通过Spearman相关分析、Passing-Bablok回归、单样本t检验、Bland-Altman散点图和Cohen's Kappa系数等对检测结果统计分析。结果:共收集到44份血液样本,FICA和ELISA法检测IFX结果的Spearman系数为0.87(P<0.01)。Passing-Bablok回归分析显示,FICA和ELISA法检测IFX结果的回归方程为CFICA=0.5071CELISA+0.6230。单样本t检验提示2种方法检测IFX结果差值与0有显著差异。Bland-Altman散点图显示FICA与ELISA法所测IFX血药浓度的差值中有91.43%(32/35)在一致性界限内(差值均值±1.96 SD)。对2种分析方法检测IFX结果定性分析表明一致性为68.18%(30/44),Cohen's KAppa系数为0.51。结论:FICA与ELISA法检测IFX结果高度相关,但一致性存在差异。ELISA法所测IFX浓度结果高于FICA,提示运用IFX检测结果进行临床决策时要关注检测方法。  相似文献   
3.
目的 了解长沙地区无偿献血人群隐匿性乙型肝炎病毒感染(occult hepatitis B virus infection,OBI)流行情况,探讨HBV基因型分布特征和S区氨基酸突变的情况。方法 对长沙地区检测结果为HBsAg-/HBV DNA+的无偿献血血液样本进行HBV血清标志物检测,对其中的OBI样本进行HBV病毒载量检测和S区基因扩增,分析血清学标志物抗HBs与病毒载量检出与否的关系,并对扩增产物进行HBV基因分型和突变位点分析。结果 2019年1月—2020年1月长沙地区173 893份无偿献血标本共确认58例OBI样本,OBI流行率为0.033%;共发现7种血清学模式,抗HBc单独阳性最多,占38.98%,所有样本中抗HBc阳性率为89.83%;16例样本能检测出病毒载量,其中14例样本浓度小于100 IU/ml;抗HBs阳性组和阴性组间的病毒载量检出率无统计学差异;75.0%(12/16)样本扩增出S区序列,基因型均为B型,均发生突变,其中11例的HBsAg抗原决定簇及周边主要亲水区域(major hydrophilic region, MHR)发生氨基酸突变。结论 长沙地区无偿献血者中的OBI感染率在全国属于偏低水平;HBV基因型主要是B型,MHR区的氨基酸突变可能是造成OBI的原因,突变有本地特点。  相似文献   
4.
目的:探讨葛根芩连汤上调微RNA-542-3p(miR-542-3p)表达保护溃疡性结肠炎(UC)大鼠的机制研究。方法:选取8~10周龄SD大鼠经UC造模及鉴定后分成模型组、美沙拉嗪组、葛根芩连汤低剂量、中剂量、高剂量组,同批次等体质量健康大鼠作为空白对照组,每组16只。UC结肠细胞进入对数生长期后消化传代至24孔板培养,每孔加入2×105个细胞,用Lipofectamine 3000转染miR-NC、miR-542-3p、anti-miR-NC、anti-miR-542-3p质粒至UC大鼠结肠上皮细胞并分组,miR-NC、miR-542-3p组细胞经含10%生理盐水处理24 h,而anti-miR-NC、anti-miR-542-3p组用含10%葛根芩连汤处理24 h,处理结束后分析细胞上清液炎症介质和氧化应激相关指标的变化。酶联免疫吸附试验法(ELISA)检测大鼠结肠组织和细胞肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、白细胞介素-8(IL-8)含量;化学比色法检测丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)含量;实时荧光定量聚合酶链式反应(RT-qPCR)检测miR-542-3p表达水平。结果:与模型组比较,葛根芩连汤中剂量、高剂量组TNF-α、IL-6、IL-8含量显著降低(P<0.05)。与模型组比较,葛根芩连汤中剂量、高剂量组MDA水平显著降低,SOD、GSH-PX水平显著升高(P<0.05)。与模型组比较,葛根芩连汤中、高剂量组miR-542-3p表达水平显著升高(P<0.05)。与UC+miR-NC组比较,UC+miR-542-3p组细胞miR-542-3p表达水平显著升高;TNF-α、IL-6、IL-8含量显著降低;MDA水平显著降低以及SOD、GSH-Px水平显著升高(P<0.05)。与UC+anti-miR-NC+葛根芩连汤组比较,UC+anti-miR-542-3p+葛根芩连汤组细胞miR-542-3p表达水平显著降低;TNF-α、IL-6、IL-8含量显著升高;MDA水平显著升高以及SOD、GSH-Px水平显著降低(P<0.05)。结论:葛根芩连汤上调miR-542-3p表达保护UC大鼠,消除肠道炎症。  相似文献   
5.
ObjectiveTo study the clinical features and identify unique renal neoplasia subtypes and their prognostic implications in individuals with tuberous sclerosis complex (TSC).Patients and MethodsThe Mayo Clinic nephrectomy registry included 37 patients with TSC diagnosed between 1970 and 2018. Four additional patients were identified from the pathology consultation and autopsy files. All available renal tumors were further characterized using immunohistochemistry and fluorescence in situ hybridization. Clinicopathologic features and follow-up were obtained from the medical record. The American Association for Cancer Research Project GENIE registry was accessed using cBioPortal for molecular profiling of angiomyolipoma (AML).ResultsA total of 276 renal tumors from 41 patients were analyzed. Renal tumors were classified into 9 distinct morphological subtypes, with AML predominating (238 [86%]). Interestingly, all these tumors acted in a benign fashion except one renal cell carcinoma with clear cells and fibromyomatous stroma and one epithelioid AML that metastasized. Molecular profiling studies revealed that epithelioid AMLs were enriched for alterations of TP53, RB1, and ATRX. Eight patients died of direct complications of TSC, including 3 of end-stage renal disease. To date, none have died of a renal epithelial neoplasm.ConclusionThe identification of unique renal neoplasia subtypes may provide important clues to establish a diagnosis of TSC, and in the somatic setting, this finding has important implications for accurate prognostication. These tumors tend to be indolent, and only 2 of 276 tumors in our study exhibited metastatic behavior. Our results support multidisciplinary management with a focus on preservation of renal function.  相似文献   
6.
BackgroundTo describe our technique for using an intraureteral injection of indocyanine green (ICG) and visualization under near-infrared fluorescence (NIRF) to facilitate challenging upper urinary tract reconstructions (UUTRs) and to present the comparative outcomes.MethodsWe collected 36 patients who underwent laparoscopic UUTRs between April 2019 and March 2020, and we divided the patients into two groups based on the use of ICG (ICG group and non-ICG group). Demographic characteristics, perioperative outcomes, and functional outcomes were compared between the two groups.ResultsThere were 18 cases in the ICG group and 18 cases in the non-ICG group, respectively. There were no differences in the baseline characteristics between the two groups. The intraoperative time to identification of the ureter (TIU; 20.9±11.7 vs. 30.0±14.6 min, P=0.03) and length of postoperative hospital stay (LPHS; 11.1±3.0 vs. 16.6±10.0 days, P=0.03) were significantly shorter in the ICG group. There was also a trend for lesser time for locating the stricture (43.0±27.9 vs. 55.4±18.6 min, P=0.14) and lower estimated blood loss (EBL) in the ICG group patients (88.3±75.4 vs. 91.7±46.2 mL, P=0.22). During the mean 3.8-month follow-up for the ICG group and the 6.2-month for the non-ICG group, there was a trend for more severe complications in the non-ICG group.ConclusionsVisualizing intraureteral ICG under NIRF is useful in challenging UUTRs, allows for rapid ureteral identification and accurate real-time delineation of the ureteral stricture margins, and provides encouraging follow-up outcomes compared with those in the non-ICG group.  相似文献   
7.
Superficial amorphization and re-crystallization of silicon in <111> and <100> orientation after irradiation by femtosecond laser pulses (790 nm, 30 fs) are studied using optical imaging and transmission electron microscopy. Spectroscopic imaging ellipsometry (SIE) allows fast data acquisition at multiple wavelengths and provides experimental data for calculating nanometric amorphous layer thickness profiles with micrometric lateral resolution based on a thin-film layer model. For a radially Gaussian laser beam and at moderate peak fluences above the melting and below the ablation thresholds, laterally parabolic amorphous layer profiles with maximum thicknesses of several tens of nanometers were quantitatively attained. The accuracy of the calculations is verified experimentally by high-resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray spectroscopy (STEM-EDX). Along with topographic information obtained by atomic force microscopy (AFM), a comprehensive picture of the superficial re-solidification of silicon after local melting by femtosecond laser pulses is drawn.  相似文献   
8.
目的探讨睾丸旁脂肪肉瘤的临床病理学特征及鉴别诊断。方法收集2012至2020年北京大学第三医院手术切除病例(11例)及外院会诊病例(8例), 经组织学、免疫组织化学EnVision法及荧光原位杂交(FISH)检测确诊。结果 19例患者, 年龄37~84岁, 中位年龄57岁。临床初步诊断为精索/腹股沟肿物(9例)、阴囊肿物(7例)和腹股沟疝(3例)。6例为复发病例, 均发生在肿物局部切除后, 其中1例为盆腔原发肿瘤局部蔓延所致。组织学类型包括10例高分化脂肪肉瘤(WDLPS)和9例去分化脂肪肉瘤(DDLPS)。WDLPS以脂肪瘤样-硬化性-炎症性亚型混合存在多见(6例), 4例为单纯脂肪瘤样;DDLPS有低级别(3例)和高级别(6例)去分化, 呈黏液纤维肉瘤样、炎症性肌纤维母细胞瘤样、纤维肉瘤样、多形性未分化肉瘤和多形性脂肪肉瘤样结构。5例WDLPS和2例DDLPS有明显炎性细胞反应。3例伴有骨化, 包括2例WDLPS和1例DDLPS。免疫组织化学显示, 脂肪分化细胞、WDLPS区的梭形间质细胞和DDLPS区的去分化细胞均表达MDM2(8/10)和CDK4(10/10);S-100蛋白表...  相似文献   
9.
《Immunobiology》2022,227(6):152283
The claudin 18.2(CLDN18.2) antigen is highly expressed in gastric mucosa epithelial cells and frequently expressed in malignant tumors. Positive clinical outcomes have popularized claudin 18.2 as a novel cellular and antibody therapeutic. Here, we designed a bispecific antibody-ZWB67 using the XFab® platform, aimed at redirecting CD3+ effector T cells to CLDN18.2+ target cells or tissues. Physicochemical characterization, binding properties, T cell stimulatory activity, and T cell-dependent cellular cytotoxicity of ZWB67 were evaluated in dosage intervals using antigens of CD3 and target cells expressing CLDN18.2 or CD3. Then, the anti-tumor activity was assessed in humanized CD3EDG mice bearing MC-38-hCLDN18.2 tumors. Our data demonstrate that ZWB67 specifically binds to the human CD3e antigen (KD = 1.04E?08 M) and binds more strongly to CLDN18.2+ cells than to CD3+ cells (4.3- to 9.2-fold difference). ZWB67 showed good activity in the luciferase reporter system and exhibited dose-dependent activation, cytotoxicity of T cells, and cytokine release when co-cultured with CLDN18.2+ cells and CD3+ T cells. ZWB67 also exhibited high in vivo efficacy in the MC-38-hCLDN18.2 xenograft mouse model. In conclusion, the novel anti-CLDN18.2 × anti-CD3 bispecific antibody exhibited low affinity for anti-CD3, highly specific binding, potent cytotoxicity, and anti-tumor activity. These data provide a basis for future preclinical and clinical development of this therapeutic strategy.  相似文献   
10.
The work-up of melanocytic tumors has undergone significant changes in the last years following the exponential growth of molecular assays. For the practicing pathologist it is often difficult to sort through the myriad of different tests available currently for clinical use. The molecular tests used in melanocytic pathology can be broadly divided into 4 categories: (i) Tests useful in the differential diagnosis of nevus versus melanoma (primarily used as an aid in the diagnosis of histologically ambiguous melanocytic tumors), (ii) Tests that predict prognosis in melanoma, (iii) Tests useful in the classification of melanocytic tumors and (iv) Tests that predict response to systemic therapy in melanoma. This review will present an updated overview of major ancillary tests used in clinical practice.  相似文献   
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