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Abstract: The present study was undertaken to examine the adaptive changes occurring 1 and 6 months after moderate or severe unilateral 6-hydroxydopamine-induced lesions confined to the lateral part of the rat substantia nigra pars compacta (SNC). The expression of tyrosine hydroxylase (TH) enzyme was analyzed in the remaining dopaminergic nigral cell bodies and in the corresponding striatal nerve endings. In the cell bodies of the lesioned SNC, TH mRNA content was increased (+20 to +30%) 6 months after the lesion without changes in cellular TH protein amounts. The depletion of TH protein in the nerve terminal area was less severe than the percentage of cell loss observed in the SNC at 1- and 6-month postlesion intervals. Moreover, the decrease in TH protein in the ipsilateral striatum was less pronounced 6 months after lesion than 1 month after. That no corresponding change in TH protein content was observed in the cell bodies at a time when TH increased in nerve terminals suggests that the newly synthesized protein is probably rapidly transported to the striatal fibers. These results suggest the existence of a sequence of changes in TH expression between cell bodies and fibers, occurring spontaneously after partial denervation of the nigrostriatal pathway.  相似文献   
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Using a probe isolated from a human liver cDNA library, polymorphisms were observed in the human ceruloplasmin gene with the enzymes PstI and MspI. The PstI polymorphism was frequent (allele frequencies, 0.46 and 0.54) whereas the polymorphisms found with MspI were rare.  相似文献   
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We have determined the parental origin of the deleted chromosome 22 in 29 cases of DiGeorge syndrome (DGS) using a CA-repeat mapping within the commonly deleted region, and in one other case by using a chromosome 22 short arm heteromorphism. The CA-repeat was informative in 21 out of 29 families studied and the deleted chromosome was of maternal origin in 16 cases (72%). When these data are pooled with recent results from the literature, 24 de novo DGS, velo-cardio-facial syndrome (VCFS) and isolated conotruncal cardiac disease deletions are found to be of maternal origin and 8 of paternal origin, yielding a 2 of 8 with a probability level lower than 0.01. These data, and review of the literature on familial DGS/VCFS and isolated conotruncal cardiopathies suggest that there is a strong tendency for the 22q11.2 deletions to be of maternal origin.  相似文献   
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A method for detecting two alleles at Np-1 (nucleoside phosphorylase) and three alleles at Es-10 (esterase 10) from mouse blood by cellulose acetate electrophoresis is described. The allelic constitution at these loci for 44 inbred strains and stocks was determined. The location of Np-1 on chromosome 14 was established by backcross experiments in which alleles at Np-1 and Robertsonian translocations were segregating. Es-10 was shown to be linked to Np-1, and the following genetic map of Chr 14 was constructed: centromere-(8.9±4.0 cM)-[Np-1, Wc]-(10.2±1.9 cM)-Es-10-(15.5±3.7 cM)-s. The homologous human loci, NP and ES-D, are not linked.This work was supported by Contract E(11-1)-3267 with the Energy Research and Development Administration, by Contracts NO1-ES4-2156 and NO1-ES4-2159 with the National Institute of Environmental Health Sciences, and by Grants GM 19656 and GM 20919 from the National Institute of General Medical Sciences. D. A. K. was a participant in the 1975 Summer Program for College, Graduate, and Medical Students, which was supported, in part, by the Clark Foundation. The Jackson Laboratory is fully accredited by the American Association for Accreditation of Laboratory Animal Care.  相似文献   
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Fused (fu) is a segment polarity gene whose product is maternally required in the posterior part of each segment. To define further the role of fused and determine how it interacts with other segmentation genes, we examined the phenotypes obtained by combining fused with mutations of pair rule, homeotic and other segment polarity loci. When it was possible, we also looked at the distribution of corresponding proteins in fused mutant embryos. We observed that fused-naked (fu;nkd) double mutant embryos display a phenotypic suppression of simple mutant phenotypes: both naked cuticle and denticle belts, which would normally have been deleted by one of the two mutants alone, were restored. In fused mutant embryos, engrailed (en) and wingless (wg) expression was normal until germ band extension, but partially and completely disappeared respectively during germ band retraction. In the fu;nkd double mutant embryo, en was expressed as in nkd mutant at germ band extension, but later this expression was restricted and became normal at germ band retraction. On the contrary, wg expression disappeared as in fu simple mutant embryos. We conclude that the requirements for fused, naked and wingless activities for normal segmental patterning are not absolute, and propose mechanisms by which these genes interact to specify anterior and posterior cell fates.  相似文献   
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Journal of Comparative Physiology A - A/J mice differ from C57BL/6J mice in the time of the daily peak of activity of glyceraldehyde-3-phosphate dehydrogenase (GAPD) in thymus and in thyroid....  相似文献   
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Biological pathways play an important role in the occurrence, development and recovery of complex diseases, such as cancers, which are multifactorial complex diseases that are generally caused by mutation of multiple genes or dysregulation of pathways. We propose a path-specific effect statistic (PSE) to detect the differential specific paths under two conditions (e.g. case VS. control groups, exposure Vs. nonexposure groups). In observational studies, the path-specific effect can be obtained by separately calculating the average causal effect of each directed edge through adjusting for the parent nodes of nodes in the specific path and multiplying them under each condition. Theoretical proofs and a series of simulations are conducted to validate the path-specific effect statistic. Applications are also performed to evaluate its practical performances. A series of simulation studies show that the Type I error rates of PSE with Permutation tests are more stable at the nominal level 0.05 and can accurately detect the differential specific paths when comparing with other methods. Specifically, the power reveals an increasing trends with the enlargement of path-specific effects and its effect differences under two conditions. Besides, the power of PSE is robust to the variation of parent or child node of the nodes on specific paths. Application to real data of Glioblastoma Multiforme (GBM), we successfully identified 14 positive specific pathways in mTOR pathway contributing to survival time of patients with GBM. All codes for automatic searching specific paths linking two continuous variables and adjusting set as well as PSE statistic can be found in supplementary materials.  The proposed PSE statistic can accurately detect the differential specific pathways contributing to complex disease and thus potentially provides new insights and ways to unlock the black box of disease mechanisms.  相似文献   
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