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1.
国人胚胎肾脏发育的超微结构研究:Ⅰ.肾小体的发育   总被引:1,自引:0,他引:1  
  相似文献   
2.
包皮过长和包茎组织中触觉小体观察   总被引:5,自引:2,他引:3  
目的观察包茎和包皮过长组织中触觉小体差异情况。方法收集21~25岁年龄组包皮标本44例,按包皮解剖形态分为:①包茎组21例;②包皮过长组23例。用免疫组化方法对两组包皮标本中的触觉小体进行染色,在放大100倍的视野下观察和统计两组包皮标本中触觉小体总数以及视野的总数,并用卡方检验对两组间的差异进行统计学分析。结果两组标本中,分别有8个(8/21包茎组)和10个(10/23包皮过长组)标本中未发现触觉小体,其差异无显著性(P=0.717)。包茎组和包皮过长组中触觉小体的密度分别为33.1%和21.1%,差异具显著性(P=0.022)。结论包茎中触觉小体密度较包皮过长明显升高可能是一种生理性代偿机制,而两种包皮组织中触觉小体的消失可能遵循同一规律。  相似文献   
3.
BACKGROUND: Nevic corpuscle (NC), a stacked lamellar structure reminiscent of Meissner corpuscle, is frequently observed in dermal melanocytic nevi. Although the heading 'neurotized' is classically used for these nevi, the exact neural nature of NC has been a topic of considerable debate. Neurotized nevi have received little attention in the dental literature, and there was no information on NC in oral melanocytic nevi. METHODS: Six cases of oral intramucosal nevi with a significant number of NC (two completely and four partially neurotized nevi) were examined immunohistochemically and ultrastructurally. RESULTS: NC was composed of closely piled laminar cells devoid of visible melanin. NC and associated spindle nevus cells were immunopositive for S-100 protein but negative for HMB-45, myelin basic protein and epithelial membrane antigen. Within NC, no reactivity for neurofilament protein, protein gene product 9.5 or peripherin was evident. Numerous CD34-positive dendritic cells were located between nevus cells and often encircled NC. Ultrastructurally, NC consisted of concentrically layered elongated cells with a slender lamellated cytoplasm rich in thin filaments and pinocytotic vesicles. Their cytoplasmic processes were focally covered by external basal lamina and continuous to spindle nevus cells. Occasional NC cells contained a few melanosomes. There was no interposed axon in NC. CONCLUSIONS: Despite the close resemblance to Meissner corpuscle, NC showed no axonal supply. NC cells lacked terminal Schwannian differentiation and appeared to be modified melanocytes with some perineurial ultrastructural characteristics. The presence of CD34-positive cells, presumably corresponding to endoneurial fibroblasts, further supports an organizational relationship of NC and peripheral nerve sheath elements.  相似文献   
4.
应用光、电镜对3~20周22例人胚和胎儿肾小体的组织发生进行了观察.受精后第25天胚肾已有肾小体发生.随着胚龄的增长,肾小体的发生数目增多,肾小体的形成方式是:胚肾内先形成许多厚壁小管,在一部分厚壁小管的诱导下,另一部分厚壁小管的一侧壁呈帽状增厚,分化形成造血干细胞、毛细血管内皮及肾小囊脏层,对侧壁形成肾小囊壁层.即厚壁小管的双侧壁形成肾小体.  相似文献   
5.
This study concerns the significance of aberrant (nuclear/cytoplasmic) expression of beta-catenin in pancreatoblastoma (PBL). On immunohistochemistry, all seven PBLs examined showed nuclear/cytoplasmic expression of beta-catenin, predominantly in the squamoid corpuscles (SCs). In areas with acinar/ductular differentiation, few tumour cells displayed nuclear/cytoplasmic expression of beta-catenin and more than half of the tumour cells showed membranous expression. Two out of five (40%) tumours examined showed missense mutations in codons 33 and 37 of exon 3 of the beta-catenin gene. No mutation of the adenomatous polyposis coli (APC) gene was detected in two of the remaining three tumours. Amplifiable DNA for APC analysis was not obtained from the one other tumour. Immunoreactivity for cyclin D1, one of the nuclear targets of beta-catenin, was found predominantly in the SCs of the seven tumours. In contrast, the Ki-67 labelling index was 2-4% (median 3%) in the SCs and 8-18% (median 12%) in the other areas, indicating a negative correlation with nuclear cyclin D1 reactivity. These results imply that in PBLs, nuclear/cytoplasmic accumulation of beta-catenin and overexpression of its target gene cyclin D1 are not associated with the induction of tumour cell proliferation. Nuclear/cytoplasmic accumulation of beta-catenin may be related to the morphogenesis of the SCs that are considered most characteristic for PBL.  相似文献   
6.
末梢血样品放置时间对血细胞测定的影响   总被引:1,自引:0,他引:1  
佘仕金  郭勇 《淮海医药》2005,23(1):26-27
目的 探讨末梢血样品放置时间对血细胞分析结果的影响。方法 在雅培 CD- 170 0型自动血液分析仪上采用平行对比法对 2 6例健康人末梢血分别在即刻、30 min、1h、2 h、4 h、8h、16 h 7个时间点的测定结果进行比较。结果  WBC有逐渐增高的趋势 ,但差异无显著性 ;MID%在 30 min时最佳 ,以后逐渐增高 ;MPV及 PL T随时间延长而不断增加 ,2 h以后与即刻结果差异有显著性。结论 末梢血样品在室温较低 (<15℃ )的情况下 ,30 min~ 8h以内测定结果最佳  相似文献   
7.
Meissner's corpuscles are the most abundant sensory corpuscles in the glabrous skin of the male prepuce. They are type I, rapidly adapting, low-threshold mechanoreceptors, and their function is linked to the expression of the mechanoprotein piezo-type mechanosensitive ion channel component 2 (PIEZO2). Stimulation of genital Meissner's corpuscles gives rise to sexual sensations. It has been recently demonstrated that digital Meissner's corpuscles, Meissner-like corpuscles, and genital end bulbs have an endoneurium-like capsule surrounding their neuronal elements; that is, the axon and glial lamellar cells, and their axons, display PIEZO2 immunoreactivity. It is unknown whether this is also the case for preputial Meissner's corpuscles. Furthermore, the expression of certain proteins that have been found in Meissner's corpuscles at other anatomical locations, especially in the digits, has not been investigated in preputial Meissner's corpuscles. Here, we used immunohistochemistry to investigate the expression of axonal (neurofilament, neuron-specific enolase), glial (S100 protein, glial fibrillary acidic protein, vimentin), endoneurial (CD34), and perineurial (glucose transporter 1) markers in the preputial and digital Meissner's corpuscles of male participants aged between 5 and 23 years. Furthermore, we investigated the occurrence of the mechanoprotein PIEZO2 in male preputial Meissner's corpuscles. Human male prepuce contains numerous Meissner's corpuscles, which may be grouped or isolated and are regularly distributed in the dermal papillae. Lamellar glial cells display strong expression of S100 protein and vimentin but lack expression of glial fibrillary acidic protein. In addition, they show axonal PIEZO2 expression and have an endoneurial capsule, but no perineurial. Our results indicate that human male preputial Meissner's corpuscles share the immunohistochemical profile of digital Meissner's corpuscles, which is considered to be necessary for mechanotransduction. These data strongly suggest that the structure and function of Meissner's corpuscles are independent of their anatomical location.  相似文献   
8.
Both Asian (Elephas maximus) and African (Loxodonta africana) elephants produce low-frequency, high-amplitude rumbles that travel well through the ground as seismic waves, and field studies have shown that elephants may utilize these seismic signals as one form of communication. Unique elephant postures observed in field studies suggest that the elephants use their feet to 'listen' to these seismic signals, but the exact sensory mechanisms used by the elephant have never been characterized. The distribution, morphology and tissue density of Pacinian corpuscles, specialized mechanoreceptors, were studied in a forefoot and hindfoot of Asian elephants. Pacinian corpuscles were located in the dermis and distal digital cushion and were most densely localized to the anterior, posterior, medial and lateral region of each foot, with the highest numbers in the anterior region of the forefoot (52.19%) and the posterior region of the hindfoot (47.09%). Pacinian corpuscles were encapsulated, had a typical lamellar structure and were most often observed in large clusters. Three-dimensional reconstruction through serial sections of the dermis revealed that individual Pacinian corpuscles may be part of a cluster. By studying the distribution and density of these mechanoreceptors, we propose that Pacinian corpuscles are one possible anatomic mechanism used by elephants to detect seismic waves.  相似文献   
9.
目的探讨NLRP3/IL-1β/TGF-β1信号轴在矽肺肺纤维化大鼠模型中的表达情况及意义。方法选择健康SPF级Wistar雄性大鼠80只,随机分为4组,分别为高(100 mg/ml)、中(50 mg/ml)、低(25 mg/ml)浓度SiO2染尘组和正常对照组,每组20只。各组分别在SiO2染尘后7 d、14 d、28 d、56 d处死5只大鼠,观察肺组织肺泡炎程度及肺纤维化程度,采用酶联免疫吸附试验(ELISA)检测肺组织中IL-1β、IL-18、TGF-β1含量,Western Blot法检测大鼠肺组织中NLRP3、Caspase-1蛋白表达情况。结果与正常对照组比较,各染尘组大鼠7 d、14 d、28 d、56 d的肺泡炎评分、纤维化程度明显升高,差异均有统计学意义(P<0.01);与正常对照组比较,各染尘组大鼠7 d、14 d、28 d、56 d的IL-1β、IL-18、TGF-β1浓度明显升高(P<0.01);与正常对照组比较,各染尘组大鼠肺组织中NLRP3、Caspase-1蛋白表达在7 d、14 d、28 d、56 d均升高(P<0.01);低、中、高浓度SiO2染尘组内NLRP3、Caspase-1、IL-1β、IL-18和TGF-β1表达量在7 d、14 d和28 d间两两比较,差异均有统计学意义(P<0. 05),均呈随着染尘时间的增加而升高的时间-效应关系。结论NLRP3及其下游因子Caspase-1、IL-1β、IL-18、TGF-β1在矽肺肺纤维化大鼠模型肺组织中高表达,提示NLRP3/IL-1β/TGF-β1信号轴可能与矽肺肺纤维化有密切的关系,在矽肺形成过程中发挥了作用。  相似文献   
10.
目的保证血细胞分析结果的溯源性和准确性。方法参照国际血液学标准化委员会及卫生部临床检验中心的有关标准,制定科学的溯源途径(方法),采取一系列的质量保证措施并予以实施。结果保证了二级标准检测系统结果的精密度和准确性,为血细胞分析常规检测系统进行校准、鉴定和评价,为全省血细胞计数室间质评的定值提供标准,为血细胞分析的仲裁鉴定提供依据。结论科学的溯源体系的建立和全面的质量保证措施是标准实验室正常发挥作用的关键。  相似文献   
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