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101.
Localization and expression of chondromodulin-I in the rat cornea   总被引:1,自引:0,他引:1  
The localization and expression in the rat cornea of chondromodulin-I (ChM-I), an inhibitory angiogenesis factor, were examined by immunohistochemistry, Western blot analysis, ribonuclease protection assay, and real-time PCR assay. We found immunoreactivity for ChM-I in the epithelial layer but not the stromal layer or endothelial layer in the cornea, in addition to the positive ChM-I immunoreactivity in other sites in the eye such as the sclera, retina, and ciliary body. The ChM-I immunoreactivity was most intense at the outside of the basal cells and in their cytoplasm while the intensity of the immunoreactivity decreased gradually from the wing cells to the superficial cells in the corneal epithelial layer. No reactivity however, was detected in the Bowman's membrane or conjunctival epithelial cells which had continuity with the corneal epithelial cells. The expression of ChM-I mRNA was demonstrated in the cornea at one-third less intensity than that in the sclera with choroids and retinal pigment epithelium by ribonuclease protection assay and real-time PCR. ChM-I in the corneal epithelial layer may prevent neovascularization and maintain avascularity in the cornea.  相似文献   
102.
Molecular diagnosis makes a substantial contribution to precise diagnosis, subclassification, prognosis, and selection of therapy. Mutations in the PDS (SLC26A4) gene are known to be responsible for both Pendred syndrome and nonsyndromic hearing loss associated with enlarged vestibular aqueduct, and the molecular confirmation of the PDS gene has become important in the diagnosis of these conditions. In the present study, PDS mutation analysis confirmed that PDS mutations were present and significantly responsible in 90% of Pendred families, and in 78.1% of families with nonsyndromic hearing loss associated with enlarged vestibular aqueduct. Furthermore, variable phenotypic expression by the same combination of mutations indicated that these two conditions are part of a continuous category of disease. Interestingly, the PDS mutation spectrum in Japanese, including the seven novel mutations revealed by this study, is very different from that found in Caucasians. Of the novel mutations detected, 53% were the H723R mutation, suggesting a possible founder effect. Ethnic background is therefore presumably important and should be noted when genetic testing is being performed. The PDS gene mutation spectrum in Japanese may be representative of those in Eastern Asian populations and its elucidation is expected to facilitate the molecular diagnosis of a variety of diseases.  相似文献   
103.
We report on a 9-month-old boy who had duplication of the long arm of chromosome 9 [46,XY, -12, +der(12) inv ins (12;9)(p13;q32q13)mat.]. The clinical manifestations of the patient were different from those seen in distal 9q duplication. Pyloric stenosis appears to be common in cases with proximal 9q duplications.  相似文献   
104.
The corticorubral projections in adult cats are primarily uncrossed. However, early in development and after early unilateral lesions of the sensorimotor cortex, crossed corticorubral projections are also observed. The present study was performed to disclose (1) whether the crossed projections originate from neuronal subpopulations different from those producing uncrossed ones and (2) how the neurons that give rise to the crossed projections in the lesioned animals are related to those occurring in normal development. We injected fluorescent latex microspheres into the red nucleus of two groups of animals: (1) intact kittens at postnatal week 3 and (2) kittens that had received unilateral ablation of the cerebral cortex at this stage and were then allowed to survive for at least 4 weeks. Red fluorescing microspheres were injected on one side and green ones on the other. In both normal and lesioned kittens, a number of cells in the cortex were labeled as a result of the contralateral as well as the ipsilateral injections, and no difference in size or distribution was found between the cells labeled from contralateral and ipsilateral injections. More than half of the cells labeled from contralateral injections were double-labeled in both groups of animals. These results indicate that individual corticorubral cells project bilaterally in normal development as well as following unilateral lesions of the cortex. With respect to the cells producing crossed projections, they were similar in both laminar and regional distributions between the intact and lesioned animal, suggesting that the crossed projections arise from the same neuronal subpopulation before and after cortical lesions. This view was supported by sequential injections of the tracers, which indicated that cells normally projecting contralaterally maintained the crossed projection after the lesions. Taking into account our previous observations that growth and proliferation of crossed corticorubral axons took place in the red nucleus (Murakami et al. 1991a), it is likely that growth and proliferation of the axons in denervated targets play a major role in lesion-induced establishment of aberrant projections.  相似文献   
105.
106.

Background  

The purpose of this study is to explore laypersons' attitudes toward the use of archived (existing) materials such as medical records and biological samples and to compare them with the attitudes of physicians who are involved in medical research.  相似文献   
107.
The thymoma prone BUF/Mna (B) rat is a useful model for Studying the genes responsible for thymus enlargement during the stage of young growth. Among the strains of rats, B rats have the largest thymuses at al stages of life. A locus, Ten-1 , which contributes to thymus enlargement in back-cross (BC) rats between the B and WKY/NCrj (W) strains, was mapped on chromosome 1. To determine the precise location of the bus, (B×(B×MITE)F1) BC rats were generated by crossing the B strain with the Inbred MITE (M) strain, which was established from captured, Japanese wild rats, and were examined by linkage study using polymerase chain reaction with 67 microsatellite markers. Linkages with thymus enlargements were found In genotypes of seven markers, BSIS, LSN, MYL2, IGF2, PBPC2, D1Mgh11 , and D1Mit6 , by X2-test and Student's t -test, which confirmed the presence of the genetic locus associated with thymus enlargement, Ten-1 , in this region. Paradoxically, a suppressive locus, Tsu-1 , to thymus enlargement was also found on chromosome 3, showing linkages of phenotype of the small thymus with genotypes of SCN2A, CAT D3Mit16 , and D3Mit13 . By analyses of mapmaker/exp and mapmaker/qtl, Ten-1 was mapped at 4.6 cM proximal from IGF2 locus on chromosome 1 and Tsu-1 at 4.0 cM proximal from CAT locus on chromosome 3, respectively.  相似文献   
108.
We evaluated the immunological potential of adenoidal lymphocytes from children with recurrent otitis media. Interleukin-4 release and CD69 expression were lower in adenoidal lymphocytes than in peripheral blood lymphocytes (PBL). Our results suggest that there may be a difference between the immunological potential of adenoidal lymphocytes and that of PBL in children with otitis.  相似文献   
109.
110.
Brown-Norway rats (male) were sensitized with both dinitrophenylated-bovine serum albumin (DNP-BSA) and Bordetella pertussis simultaneously in order to induce airway hyperresponsiveness (AHR) as the first sensitization. At five days, DNP-BSA was inhaled as a booster into the airways under thiopental anaesthesia. At eight days, inhalation of antigen markedly increased the tracheal pressure (TP) in sensitized rats (11.9 +/- 1.6 cmH2O) and slightly increased TP in non-sensitized rats (1.1 +/- 0.4), the difference between the two groups being significant (p less than 0.001). Twenty-four hours after antigen challenge, the airway responsiveness to ACh in sensitized rats was markedly increased to about 4-fold as compared to that in non-sensitized rats. Inhalation of dinitrophenylated-ovalbumin failed to increase the airway responsiveness to ACh in rats sensitized with DNP-BSA, although a marked increase in TP was induced immediately after antigen challenge. We thus succeeded in preparing a model of AHR by employing a new procedure of sensitization.  相似文献   
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