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排序方式: 共有74条查询结果,搜索用时 15 毫秒
1.
目的应用人精子头-尾膜完整性试验,比较生育力组与不育组男性精液4种精子膜完整性类型的差异.方法精液标本分为生育力组(n=32)和不育组(n=50),采用"低渗肿胀-伊红拒染"结合试验,检测人精子头-尾膜完整性.结果头膜尾膜均损伤的Ⅰ型精子和头膜损伤-尾膜完整的Ⅲ型精子,生育组和不育组存在明显差异(P<0.01);头膜完整-尾膜损伤的Ⅱ型精子,生育组和不育组无明显差异(P>0.05);头膜-尾膜均完整的Ⅳ型精子,生育组明显高于不育组(P<0.01);Ⅳ型精子率与生育组精子活动率(n=32, r=0.82,P<0.01)和不育组精子活动率(n=50,r=0.80,P<0.01)均呈显著相关性.结论生育组具有较多头膜-尾膜均完整的精子."低渗肿胀-伊红拒染"结合试验能够清晰显示包括过渡型膜损伤的4种膜完整性类型的精子,精子头-尾膜完整性可以作为评价精子生理学的一项检测指标.  相似文献   
2.
The preweaning piglet has been found to be a valuable research model for testing ingredients used in infant formula. As part of the safety assessment, the neonates' immune system is an important component that has to be evaluated. In this study three concurrent strategies were developed to assess immune system status. The methods included (1) immunophenotying to assess circulating innate immune cell populations, (2) monitoring of circulating cytokines, particularly in response to a positive control agent, and (3) monitoring of localized gastrointestinal tissue cytokines using immunohistochemistry (IHC), particularly in response to a positive control agent. All assays were validated using white papers and regulatory guidance within a GLP environment. To validate the assays precision, accuracy and sample stability were evaluated as needed using a fit for purpose approach. In addition animals were treated with proinflammtory substances to detect a positive versus negative signal. In conclusion, these three methods were confirmed to be robust assays to evaluate the immune system and GIT-specific immune responses of preweaning piglets.  相似文献   
3.
The present study investigates whether lymphatic vessel invasion (LVI) detected by D2‐40 staining is a prognostic factor for stage I adenocarcinoma of the lung. We retrospectively reviewed 124 patients who underwent complete resection for stage I adenocarcinoma of the lung from January 1983 to June 2003. LVI was microscopically evaluated using D2‐40 immunostaining. The median follow‐up was 71 months. The LVI positive rate was 37%. The 5‐year cancer‐specific survival rates of the D2‐40 positive LVI and negative groups were 88.8% and 84.3%, respectively (P = 0.630). The stage I lung adenocarcinoma patients who were determined to be LVI positive based on D2‐40 immunostaining did not have a significantly poorer prognosis than the LVI negative cases. Thus, lymphatic microinvasion may not be a prognostic indicator in early lung cancer, although advanced LVI does appear to correlate with survival. It is therefore unnecessary to use D2‐40 immunostaining to diagnose LVI in practical settings, and Hematoxylin‐Eosin and Elastica van Gieson staining should continue to be used to predict the prognosis of patients with stage I lung adenocarcinoma.  相似文献   
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目的:探讨龙胆紫染色区分存活精子和死亡精子可能性,以提供一种判定精子存活率的新方法,为男性精液检测和质量评价提供依据。方法:采用不同浓度的龙胆紫溶液对精液样本染色,在光学显微镜下观察染色结果,讨论区分存活精子和死亡精子的标准,并计数一定数量的总精子数,计算存活率,并将计算结果与标准方法比较。结果:经过龙胆紫溶液(0.05%,M/V)染色后在显微镜下存活精子呈现淡蓝色,而死亡精子呈现深紫色,计算获得的存活率与伊红染色法(0.5%,M/V)的结果比较差异统计学意义(t=0.862,双侧P=0.403)。结论:一定浓度的龙胆紫染色后能够清楚地区分存活精子和死亡精子,该法获得的精子存活率结果可靠,龙胆紫染色法可以作为一种新的分析精子存活率的方法。  相似文献   
6.
We propose a Deep learning-based weak label learning method for analyzing whole slide images (WSIs) of Hematoxylin and Eosin (H&E) stained tumor tissue not requiring pixel-level or tile-level annotations using Self-supervised pre-training and heterogeneity-aware deep Multiple Instance LEarning (DeepSMILE). We apply DeepSMILE to the task of Homologous recombination deficiency (HRD) and microsatellite instability (MSI) prediction. We utilize contrastive self-supervised learning to pre-train a feature extractor on histopathology tiles of cancer tissue. Additionally, we use variability-aware deep multiple instance learning to learn the tile feature aggregation function while modeling tumor heterogeneity. For MSI prediction in a tumor-annotated and color normalized subset of TCGA-CRC (n=360 patients), contrastive self-supervised learning improves the tile supervision baseline from 0.77 to 0.87 AUROC, on par with our proposed DeepSMILE method. On TCGA-BC (n=1041 patients) without any manual annotations, DeepSMILE improves HRD classification performance from 0.77 to 0.81 AUROC compared to tile supervision with either a self-supervised or ImageNet pre-trained feature extractor. Our proposed methods reach the baseline performance using only 40% of the labeled data on both datasets. These improvements suggest we can use standard self-supervised learning techniques combined with multiple instance learning in the histopathology domain to improve genomic label classification performance with fewer labeled data.  相似文献   
7.
秦明友 《海峡药学》2009,21(10):59-62
目的在pH3.0的弱酸性介质中,盐酸丁卡因(TA.HCl)与曙红Y(EY)形成1∶1的离子缔合物,导致曙红Y溶液在521 nm处同步荧光猝灭(Δλ=25nm)。荧光猝灭值(ΔF)与TA.HCl浓度在0.18-3.0μg.mL^-1范围呈良好的线性关系。该方法灵敏度高,检出限为0.055μg.mL^-1。考察了共存物质的影响,表明方法有良好的选择性。据此发展了一种高灵敏、简便快速测定微量TA.HCl的新荧光分光光度法。该法用于人血清及尿样中盐酸丁卡的含量测定,结果满意。  相似文献   
8.
Worldwide, there is a great need of small diameter vascular grafts that can be used in human disorders such as cardiovascular and peripheral vascular disease. Until now, severe adverse reactions are caused from the use of synthetic or animal derived grafts, while the use of autologous vessels is restricted only in a small number of patients. The limited availability of the vessels might be resolved by the use of HLA-matched vascular grafts utilizing the decellularized human umbilical arteries. In this study, human umbilical arteries were decellularized and then repopulated with Mesenchymal Stem Cells. The HLA-genotype of the repopulated grafts, analyzed by Next Generation Sequencing technology, indicated their successful production. The HLA-matched vascular grafts could be generated efficiently and might be used in personalized medicine.  相似文献   
9.
本文应用不同浓度精子低渗肿胀试验结合伊红染色法,对8例生育男性和10例不育男性的精子膜功能进行评估。结果表明:1.活精子尾部低渗肿胀率均达到90%以上,生育组与不育组无显著性差异;2.在150mOsm低渗溶液的稀释倍数为3~7倍之间,精子头部膜的损害程度在生育组与不育组之间存在显著性差异;3.在不同浓度的低渗溶液中,精子头部膜与精子尾部膜对低渗溶液的顺应性并不一致。实验证明不同浓度低渗肿胀试验结合伊红染色可正确评价精子膜的整体功能。  相似文献   
10.
A multi-classifier diagnostic system was designed for distinguishing between benign and malignant thyroid nodules from routinely taken (FNA, H&E-stained) cytological images. To construct the multi-classifier system, several combination rules and different mixtures of ensemble classifier members, employing morphological and textural nuclear features, were comparatively evaluated. Experimental results illustrated that the classifier combination k-NN/PNN/Bayesian and the majority vote rule enhanced significantly classification accuracy (95.7%) as compared to best single classifier (PNN: 89.6%). The proposed system was designed with purpose to be utilized in daily clinical practice as a second opinion tool to support cytopathologists' decisions, when a definite diagnosis is difficult to be obtained.  相似文献   
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