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81.
82.
Aim: Differential diagnosis, including the respective distinctions between benign and malignant tumors, follicular and papillary neoplasms, and follicular adenoma and follicular carcinoma, are always required in clinical practice, because therapeutic strategy largely depends on the diagnosis made. Methods: The present study describes a novel approach to obtaining clinically useful markers by means of the simultaneous comparison of multiple molecules using tissue array analysis. The markers examined in this study include galectin‐3, CD44v6, p53, HBME‐1, maspin and S100A4, which were reportedly useful for making these distinctions in association with metastasis and invasion. A total of 45 cases of thyroid tumors (seven adenomatous goiters, 16 follicular adenomas, 12 follicular carcinomas and 10 papillary carcinomas) were analyzed. Results: The results demonstrated the following suggestive phenotypes: galectin‐3, HBME‐1 and maspin+ as benign lesions, galection‐3, HBME‐1+ and maspin as follicular carcinoma, and galectin‐3+, HBME‐1+ and maspin+ as papillary carcinoma. Conclusions: The expression of the molecules was assessed in each case and the expression profiles were compared. Useful multiple molecules were selected for each distinction and were correlated with each other. To understand the complex relationship, a logistic regression model was constructed. These results suggested that combined analysis of multiple molecules enhanced the differential diagnostic accuracy.  相似文献   
83.
84.
We describe a 37-year-old man complaining of right back pain and gait disturbance. He had a big soft tumor on his right back, hemihypertrophy of the right lower extremity, and right thoracic scoliosis. We diagnosed Klippel-Trenaunay-Weber syndrome based on the pathological findings of the soft tumor. Computed tomography (CT) scan revealed severe spinal stenosis due to a hypertrophic vertebral body and facet joint at T7. Treatment by decompression of hypertrophic bone led to complete neurological recovery. To our knowledge, no case has been reported of Klippel-Trenaunay-Weber syndrome with myelopathy which originated from thoracic scoliosis with a hypertrophic facet joint and vertebral body. We suggest that the cause of myelopathy in Klippel-Trenaunay-Weber syndrome originated not only from arteriovenous fistula, medullary angioma, and extradural hemangioma but also vertebral hypertrophy with scoliosis.  相似文献   
85.
Objectives Several studies have reported that the secretory immunoglobulin A (S-IgA) concentration in saliva is an indicator of psychological stress. The aim of this study was to clarify the relationship between S-IgA and the stress from academic examinations. Methods S-IgA levels in 10 medical student volunteers from the second year course between May 4 and July 13, 2000 were examined using the ELISA method. Results There was a tendency for S-IgA in saliva to be higher on the day before academic examinations and during them, and lower on the days between these examinations. Conclusions It may be possible to use this measurement to monitor psychological stress in students and workers. Second year medical student in the year 2000.  相似文献   
86.
The synaptic organization of afferents to the parafascicular nucleus (Pf) of the thalamus was studied in rats. In the Pf, three types of axon terminals were identified: the first type was a small terminal with round synaptic vesicles forming an asymmetric synapse, the second type was a large terminal with round synaptic vesicles forming an asymmetric synapse, and the third type was a terminal with pleomorphic vesicles forming a symmetric synapse. They were named SR, LR and P boutons, respectively. In order to determine the origin of these axon terminals, biotinylated dextran amine (BDA) was injected into the main afferent sources of the Pf, the superior colliculus (SC) and the pedunculopontine tegmental nucleus (PPN). Axon terminals from the SC were both SR and LR boutons which made synaptic contacts with somata and dendrites. PPN afferents were SR boutons, which made synaptic contacts with somata and smaller dendrites. Double-labeled electron microscopic studies, in which a retrograde tracer (wheat germ agglutinin conjugated to horseradish peroxidase: WGA-HRP) was injected into the striatum and an anterograde tracer (BDA) into the SC revealed that SC afferent terminals made synapses directly with Pf neurons that projected to the striatum. Another experiment was performed to find out whether two different afferents converged onto a single Pf neuron. To address this question, two different tracers were injected into the SC and PPN in a rat. Electron microscopically, both afferent terminals from the SC and PPN made synaptic contacts with the same dendrite. Our results prove that a single neuron of the rat Pf received convergent projections from two different sources.  相似文献   
87.
Recently, it has been suggested that neural stem cells and neural progenitor cells exist in the ependyma that forms the central canal of the spinal cord. In this study, we produced various degrees of thoracic cord injury in adult rats using an NYU-weight-drop device, assessed the degree of recovery of lower limb motor function based on a locomotor rating scale, and analyzed the kinetics of ependymal cell proliferation and differentiation by proliferating cell nuclear antigen (PCNA), nestin, glial fibrillary acidic protein (GFAP), or GAP-43 immunostaining. The results showed that the time course of the ependymal cell proliferation and differentiation reactions differed according to the severity of injury, and that the responses occurred not only in the neighborhood of the injury but in the entire spinal cord. An increase in the locomotor rating score was related to an increase in the number of PCNA-positive cells, and the differentiation of ependymal cells into reactive astrocytes was involved in injury repair. No apoptotic cells in the ependyma were detectable by the TUNEL method. These results indicate that the ependymal cells of the spinal central canal are themselves multipotent, can divide and proliferate according to the severity of injury, and differentiate into reactive astrocytes within the ependyma without undergoing apoptosis or cell death.  相似文献   
88.
Generation of free radical and/or active oxygen by light or laser irradiation of hydrogen peroxide (H2O2) or sodium hypochlorite (NaClO), which have been used for tooth whitening or root canal irrigation, was investigated using electron spin resonance spectroscopy combined with a spin-trapping technique. When H2O2 was exposed to light or laser radiation, the amount of hydroxyl radical generated changed according to the concentration of H2O2 and irradiation time. The amount of 5,5-dimethyl-1-pyrrolidone-(2)-oxyl-(1) (DMPO-X) also changed in accordance with irradiation time. The amounts of hydroxyl radical generated from H2O2 after irradiation were in the order: plasma lamp > halogen lamp > He-Ne laser > Yellow He-Ne laser. On the other hand, the amounts of DMPO-X generated from NaClO after irradiation were in the order: plasma lamp > Yellow He-Ne laser > halogen lamp > He-Ne laser.  相似文献   
89.
The peroxisome proliferator-activated receptor (PPAR) gamma is an important regulator of adipocyte differentiation and a modulator of intracellular insulin-signaling events. We examined the roles of the Pro12Ala variant of PPAR gamma2 in obesity and insulin resistance in 402 Japanese patients with type 2 diabetes and 116 control subjects. Among the diabetes subjects, the Pro12Pro homozygotes showed significantly higher body mass index (BMI) than those with the Pro12Ala variant (p = 0.020), while there was no association between genotype and BMI in the controls. Furthermore, diabetic subjects with Pro12Pro showed significantly higher fat body mass index (FBMI) than those with Pro12Ala (p = 0.016), while no association between genotype and lean body mass index (LBMI) was observed. Regarding insulin resistance, there was no difference in the HOMA index or in clamp index between Pro12Ala and Pro12Pro variants. These data suggest that the Pro12Ala polymorphism of PPAR gamma2 does not influence insulin resistance but body composition in Japanese diabetic subjects.  相似文献   
90.
The MEGF1 (protein 1 with multiple EGF-like domains) gene, which was identified using motif-trap screening, encodes an extraordinarily large protein containing two EGF-like and 34 cadherin motifs. In situ hybridization analysis revealed that the MEGF1 gene was specifically expressed in granule cells of the cerebellum. Interestingly, in the developing cerebellum, granule cells in the inner external germinal layer and migrating granule cells expressed MEGF1 mRNA, whereas proliferating cells in the outer external germinal layer did not express MEGF1 mRNA. Expression levels in the internal granule cell layer peaked during the third postnatal week and remained considerably high in the adult cerebellum. MEGF1 protein was detected in only the cerebellum as a single 480-kDa band by immunoblot analyses using polyclonal antibodies against either the N-terminal or the C-terminal region of MEGF1 protein. Using light and electron microscopic immunocytochemistry, specific immunostaining of the MEGF1 protein was observed in the molecular layer of the cerebellum, suggesting that MEGF1 protein was localized in the parallel fibers of cerebellar granule cells. This was corroborated by results from experiments using primary dispersed cultures of cerebellar granule cells and cerebellar microexplant cultures. The homophilic interaction of MEGF1 proteins was confirmed with both a cell aggregation assay and an in vitro copurification assay. Based on these results, a novel function of the enormous protocadherins in cerebellar development, namely, the modulation of the extracellular space surrounding parallel fibers during development, was proposed.  相似文献   
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