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Sato A Taniguchi I Fujiwara D Ichikawa H Suzuki M Nawata S Murakami G 《Anatomical science international / Japanese Association of Anatomists》2003,78(4):211-222
Gaps and fragmentation of the superficial lymph node cortex are considered to provide intranodal shunt flow between the afferent
and efferent vessels. Using serial sections of 205 nodes obtained from 27 donated cadavers more than 70 years of age, we examined
the histological architecture of the abdominal and pelvic nodes in elderly Japanese. Secondary follicles were rare in the
specimens. Cortex gaps were, to a greater or lesser degree, found in all nodes. We classified these nodes into three types
according to how often the gap occurred. Type 1 nodes, with a relatively complete shield for the afferent lymph, were most
frequently found in gastric nodes, whereas type 3 nodes, with numerous gaps, were often observed in the colic, para-aortic
and pelvic nodes. The type 3 nodes showed a specific architecture characterized by a fragmented superficial cortex, three-dimensionally
assembled cords and a common sinus between them. Primary follicles were located in the assembled cord structures as well as
at the superficial cortex. Irrespective of the type, B and T lymphocyte areas were intermingled in the cortex-like areas.
The present results reveal region-specific histological heterogeneity in aged human visceral nodes. Due to increased surface
areas, the type 3 architecture seemed to accelerate systemic immunity rather than act as a local barrier in the para-aortic
and pelvic nodes, which are located centrally along the lymphatic drainage routes. However, thick trabeculae often seemed
to develop in the type 3 sinus to decrease nodal function with aging. 相似文献
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[3H]2-Deoxy-d-glucose (2-DG) was used to investigate the glucose uptake in cultured rat Schwann cells from postnatal Sprague-Dawley rat sciatic nerves. The glucose uptake of Schwann cells slightly increased in a time- and dose-dependent manner. However, the maximal uptake level was much lower than that of ethylnitrosourea (ENU)-induced transformed rat schwannoma-like cells and fibroblasts. By autoradiography of the cultured system, we were able to visualize the accumulation of [3H]2-DG grains in the schwannoma-like cells and fibroblasts, but not in Schwann cells. 相似文献
26.
Nakashima E Mabuchi A Kashimada K Onishi T Zhang J Ohashi H Nishimura G Ikegawa S 《American journal of medical genetics. Part A》2003,(3):253-256
We examined 12 Japanese patients with metaphyseal chondrodysplasia (MCD) for mutations in the ribonuclease mitochondrial RNA processing gene (RMRP), and identified four novel mutations in two patients with typical and atypical cartilage-hair hypoplasia (CHH), a form of MCD characterized by extra-skeletal manifestations including hypoplastic hair and defective immunity. A patient with typical CHH had a 17-bp duplication at +3 and a de novo 182G > A. The other patient with atypical CHH had a 17-bp insertion at -20 and a 218A > G. Expression analysis revealed that the allele with this insertion mutation in the promoter region silenced the gene. Spectrum analysis of the mutations and polymorphisms in RMRP showed marked difference between the Japanese and other ethnic groups. Such ethnic and phenotypic difference should be taken into account in mutation analysis of the gene. 相似文献
27.
Two novel mutations of the β-hexosaminidase α subunit gene were identified in Japanese patients with the infantile form of
Tay-Sachs disease. One mutation was a one-base deletion at nt613C, which generated a stop codon at two codons downstream,
in three unrelated patients. The other mutation was a one-base substitution of G-to-A at IVS 5, +1, which caused a splicing
abnormality, in one patient. A missense mutation of R170W, which has already been reported in other ethnic groups, was also
newly identified in one patient. In 1993, the most common mutation (IVS 5, −1G → T) in Japanese patients with Tay-Sachs disease
was reported as the major mutation in Japan accounting for 80% of 56 mutant alleles from 28 unrelated patients. The deletion
of nt613C was the second most common mutation, accounting for 5% of the mutant alleles. The previously reported mutation IVS
5, −1G → T and the nt613C deletion found in this study together accounted for 85% of the mutations causing Tay-Sachs disease
among Japanese. Since these two mutations were located in or close to exon 6 and since they abolish Fok I (IVS 5, −1G → T) and Sfa NI (nt613C deletion) restriction sites, respectively, they were screened rapidly by single polymerase chain reaction followed
by digestion with these enzymes.
Received: November 10, 1998 / Accepted November 14, 1998 相似文献
28.
一个快速稳定的分割系统是研究神经元干细胞变化的基础,为完善此系统,针对多连接边缘模糊的细胞分割提取问题,根据曲线进化原理,我们提出了一种基于水平集方法的改进的几何活动轮廓算法。此算法能自动解决图像的拓扑变化,并能获得更加真实的细胞轮廓边缘。将此方法应用于神经元干细胞的序列图像分割,实验结果证明了此算法的有效性与准确性。 相似文献
29.
M Solé J Cano J L Rodríguez-Tudela J Pontón D A Sutton R Perrie J Gené V Rodríguez J Guarro 《Medical mycology》2003,41(4):293-300
Invasive infections by Scedosporium prolificans have increased alarmingly in recent years, mainly in immunosuppressed patients. The epidemiology, pathogenesis and the natural habitat of this pathogen are practically unknown. Isolates of S. prolificans were distinguished from one another by inter-simple-sequence-repeat (ISSR) fingerprinting, a technique based on the high degree of polymorphism of the multisatellite genetic markers used. This technique was found useful for typing 84 isolates of S. prolificans from different countries and sources. The assemblage of S. prolificans isolates tested was extremely diverse, with 35 genotypes present. Several patients were found to have been infected or colonized by more than one strain. Overall, this technique facilitates the epidemiological study of S. prolificans infection. 相似文献
30.
研究了明胶水凝胶在绝缘硅油中的电场响应行为。结果表明,在硅油中,明胶水凝胶在外加高压直流电场作用下可发生运动,其运动由转动和平动两部分组成。存在一个运动所需的最小阈值电场,只有外加电场在此阈值以上时,才可观察到水凝胶明显的运动。水凝胶的运动速度随外加电场的增大而增大,其运动可通过外加电场的大小来调控。由硅油很稳定且在电场中会电解,因此避免了传统电场驱动水凝胶在水介质中响应时不可避免的电解缺点,为建立一种新的电响应凝毅然驱动方式提供了可能。 相似文献