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排序方式: 共有121条查询结果,搜索用时 234 毫秒
1.
The rise of antibiotic resistance has increased the need for alternative ways of preventing and treating enteropathogenic bacterial infection. Various probiotic bacteria have been used in animal and human. However, Saccharomyces boulardii is the only yeast currently used in humans as probiotic. There is scarce research conducted on yeast species commonly found in kefir despite its claimed potential preventative and curative effects. This work focused on adhesion properties, and antibacterial metabolites produced by Kluyveromyces lactis and Saccharomyces unisporus isolated from traditional kefir grains compared to Saccharomyces boulardii strains. Adhesion and sedimentation assay, slide agglutination, microscopy and turbidimetry assay were used to analyze adhesion of Salmonella Arizonae and Salmonella Typhimurium onto yeast cells. Salmonella growth inhibition due to the antimicrobial metabolites produced by yeasts in killer toxin medium was analyzed by slab on the lawn, turbidimetry, tube dilution and solid agar plating assays. Alcohol and antimicrobial proteins production by yeasts in killer toxin medium were analyzed using gas chromatography and shotgun proteomics, respectively. Salmonella adhered onto viable and non-viable yeast isolates cell wall. Adhesion was visualized using scanning electron microscope. Yeasts-fermented killer toxin medium showed Salmonella growth inhibition. The highest alcohol concentration detected was 1.55%, and proteins with known antimicrobial properties including cathelicidin, xanthine dehydrogenase, mucin-1, lactadherin, lactoperoxidase, serum amyloid A protein and lactotransferrin were detected in yeasts fermented killer medium. These proteins are suggested to be responsible for the observed growth inhibition effect of yeasts-fermented killer toxin medium. Kluyveromyces lactis and Saccharomyces unisporus have anti-salmonella effect comparable to Saccharomyces boulardii strains, and therefore have potential to control Salmonella infection.  相似文献   
2.
This paper illustrates a method for automatic data recording using the printer port of personal computer and software designed ad hoc. The system was tested by measuring circadian rhythms of activity in the subterranean rodent Ctenomys talarum. Data is recorded in a text-only comma-delimited file, and displayed on screen.  相似文献   
3.
AimTo review the literature on auto-contouring methods of lung tumour volumes on four-dimensional computed tomography (4DCT).BackgroundManual delineation of lung tumour on 4DCT has been the gold standard in clinical practice. However, it is resource intensive due to the high volume of data which results in longer contouring duration and uncertainties in defining target. Auto-contouring may present as an attractive alternative by decreasing manual inputs required, thus improving the contouring process. This review aims to assess the accuracy, variability and contouring duration of automatic contouring compared with manual contouring in lung cancer on 4DCT datasets.Materials and methodsA search and review of literature were conducted to identify studies regarding lung tumour contouring on 4DCT. Manual and auto-contours were assessed and compared based on accuracy, variability and contouring duration.ResultsThirteen studies were included in this review and their results were compared. Accuracy of auto-contours was found to be comparable to manual contours. Auto-contouring resulted in lesser inter-observer variation when compared to manual contouring, however there was no significant reduction in intra-observer variability. Additionally, contouring duration was reduced with auto-contouring although long computation time could present as a bottleneck.ConclusionAuto-contouring is reliable and efficient, producing accurate contours with better consistency compared to manual contours. However, manual inputs would still be required both before and after auto-propagation.  相似文献   
4.
Early discover of risk progression of invisible carcinomas is important for a prerequisite successful treatment. Here, we investigated whether concentration of human thymidine kinase 1 (HTK1) discover invisible malignant human tumours. The HTK1 concentration of tumour cellular based on HTK1 IgY-polyclonal-antibody (HTK1-IgY-pAb) was determined by using a novel automatic chemiluminescence analyser with sandwich biotin-streptavidin (SBSA) platform. Minimum number of cells able to be detected by this technology used cells with low and high concentration of HTK1. The limit visibility by tumour imaging is approximately 1 mm in diameter, corresponding to approximately 109 cells with a cell diameter of 1 µm. Based on a HTK1 standard curve and a molecular weight of HTK1 of 96 kD, the HTK1protein (HTK1p) concentration per cell was calculated to be 0.021 pg. Assuming 200 pg in total protein/cell, approximately 50 × 106 growing malignant cells in the body were calculated to releases HTK1 into 5-liter blood. A HTK1 values of 3.914, 0.435 and 0.009 pmol/L corresponds to 10 × 105, 2 × 105 and 1 × 105 growing malignant cells, respectively. The lowest detectable sensitivity of HTK1 is 0.009 pmol/L in 1 × 105 growing malignant cells and 0.01 pmol/L in blood serum, detectable in health screening. Comparing the novel automatic chemiluminescence analyser with the original ECL dot-blot assay using serum HTK1p (health screening, n = 265) showed high correlation (r = 0.8743, P < .000). In conclusion, the novel automatic chemiluminescence analyser with SBSA platform is a reliable method with high accuracy to determine carcinoma invisible.  相似文献   
5.
Each holotype specimen provides the only objective link to a particular Linnean binomen. Sequence information from them is increasingly valuable due to the growing usage of DNA barcodes in taxonomy. As type specimens are often old, it may only be possible to recover fragmentary sequence information from them. We tested the efficacy of short sequences from type specimens in the resolution of a challenging taxonomic puzzle: the Elachista dispunctella complex which includes 64 described species with minuscule morphological differences. We applied a multistep procedure to resolve the taxonomy of this species complex. First, we sequenced a large number of newly collected specimens and as many holotypes as possible. Second, we used all >400 bp examine species boundaries. We employed three unsupervised methods (BIN, ABGD, GMYC) with specified criteria on how to handle discordant results and examined diagnostic bases from each delineated putative species (operational taxonomic units, OTUs). Third, we evaluated the morphological characters of each OTU. Finally, we associated short barcodes from types with the delineated OTUs. In this step, we employed various supervised methods, including distance‐based, tree‐based and character‐based. We recovered 658 bp barcode sequences from 194 of 215 fresh specimens and recovered an average of 141 bp from 33 of 42 holotypes. We observed strong congruence among all methods and good correspondence with morphology. We demonstrate potential pitfalls with tree‐, distance‐ and character‐based approaches when associating sequences of varied length. Our results suggest that sequences as short as 56 bp can often provide valuable taxonomic information. The results support significant taxonomic oversplitting of species in the Elachista dispunctella complex.  相似文献   
6.
Defibrillation testing is no longer routinely performed after automatic implantable cardioverter-defibrillator (AICD) implantation. However, certain subjects undergoing AICD implantation may be at higher risk of undersensing of ventricular arrhythmias resulting in potentially fatal outcomes. We present the case of a 30-year-old woman with hypertrophic cardiomyopathy (HCM; ‘asymmetric septal hypertophy’ morphologic variant) and prophylactic AICD who experienced an out of hospital cardiac arrest. AICD interrogation revealed undersensing as a result of intermittent high amplitude electrograms during an episode of ventricular fibrillation (VF). The subject underwent replacement and repositioning of the AICD lead along with pulse generator replacement (that utilized a different VF sensing algorithm) with appropriate sensing of VF and successful defibrillation testing. The presence of intermittent high amplitude electrograms during episodes of VF in AICDs using the AGC function should be recognized as a situation that may necessitate interventions to prevent undersensing and consequent delay in therapy.  相似文献   
7.
目的通过电子芯片植入与识别技术和计算机管理系统对接,建立每只实验猴的数据档案,其中包括遗传谱系、生理数据、实验记录。方法通过建立实验猴的电子通道,以非接触方式通过计算机管理,应用射频识别信号系统,实现实验猴身份快速自动识别、自动捕捉、数据读写、电子档案信息管理、数据远程传输的目的,减少人为因素对实验猴的干扰和引起的应激反应。结果该系统的建立极大的减少了实验和饲养实验猴过程中捕捉猴的困难,身份识别困难,减少了对工作人员和实验猴的伤害,减轻了工作量,减低了人为因素对实验结果的干扰和动物应激反应对实验数据的影响。电子档案具有终身有效,随猴携带,全球唯一序列号,不可复制,不可仿制,标签唯一性。结论实验猴身份自动识别、自动捕捉、电子芯片数据信息管理系统的研制成功,为实验动物个体电子档案建立和群体数据库的管理提供了一种高速、有效、科学、可靠的计算机管理手段,改变通道模式即可应用于大型凶猛动物或不适合人接触捕捉动物的识别和管理,具有广泛的应用前景,目前在国内外尚无同类系统。  相似文献   
8.
李小溪  李筱涵  郭晓东  李波  孙志强 《生物磁学》2011,(12):2345-2346,2206
目的:探讨血浆取代血清检测乙肝标志物的检测结果以及临床意义。方法:选取我科检测乙肝标志物的血样30份,分别放在抗凝剂管和普通干燥试管,采用全自动酶免疫分析仪检测HBsAg,将检测结果进行OD及S/CO值统计处理,并进行比较分析。结果:血清与二种血浆检测结果相关系数均0.99,二种血浆与血清结果相关关系良好(P〉0.0 5),无显著性差异。结论:血浆代替血清完全可以用于全自动酶标分析仪进行检测,既可以节省预处理时间,又可以减少标本在分离吸移血清过程中出现差错,值得临床推广和应用。  相似文献   
9.
回顾了心脏电生理方法学和器械进步的早期基石,并阐述了以导管和起搏技术为特点的心内电生理学若干标志性新方法、新领域、新进展。进而展望了心脏电生理方法学的若干发展方向。  相似文献   
10.
目的研讨透视图像亮度自动控制应用的三种剂量率调整方法。方法自动调整毫安值、自动调整仟伏值、自动调整毫安和仟伏值。结果有助于保持最佳透视图像成像质量,提高临床诊断效率。结论采用自动仟伏调整和自动毫安、仟伏调整不失为行之有效的方法  相似文献   
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