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21.
Elvira D'Alessandro Corinna De Matteis Vaccarella Maria Luisa Lo Re Francesco Cappa Angela D'Alfonso Stefania Discepoli Maria Rosa Della Penna Giuseppe Del Porto 《Human genetics》1988,80(2):203-204
Summary Pericentric inversion of chromosome 19 has been found in several members of three unrelated families from a restricted geographical region. In one of the families, an additional pericentric inversion of chromosome 9 was observed. Reproductive problems, multiple abortions in two families and a neonatal death in the third, were present. A review of previously described cases is included, and the genetic risk connected with this type of rearrangement is also discussed. 相似文献
22.
Suzanne J. Suchard Hilda K. Lo Lilly Y. W. Bourguignon 《Journal of cellular physiology》1988,134(1):67-77
In this study we have used a density perturbation method to isolate anti-Thy-1 antibody-induced Thy-1 caps from mouse T-lymphoma cells in the absence of detergents, and then compared the phospholipid composit on of these capped membranes with that of uncapped membranes. Initial phospholipid analysis by two-dimensional thin layer chromatography (2-D TLC) reveals a significant increase in the amount of 32P-labeled phosphatidylcholine in the Thy-1 capped membrane. In contrast, no significant changes are observed in the labeling of phosphatidylserine, phosphatidylethanolamine, or the sphingomyelins. Therefore, it is suggested that phosphatidylcholine may be involved in the organization and/or regulation of Thy-1 antigen redistribution. The composition of phosphoinositide in uncapped and capped membranes was analysed separately using one-dimensional thin layer chromatography (1-D TLC) to resolve phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP), and phosphatidylinositol 4, 5-bisphosphate (PIP2) from all other phospholipids. This analysis reveals a significant reduction in levels of PIP and PIP2, but not PI, in Thy-1 caps. Through the use of ion exchange column chromatography, we have found an increased production of all three species of inositol phosphates during anti-Thy-1 antibody-induced capping. Inositol 1, 4, 5 -triphosphate (IP3) shows the most significant increase, compared to the much smaller increases in inositol 4, 5-bisphosphate (IP2) and inositol monophosphate (IP). These results suggest that the binding of anti-Thy-1 antibody to Thy-1 antigen activates phospholipase C which, in turn, initiates polyphosphoinositide turnover and IP3 production. It is proposed that these observed effects are the result of early signal transducing events which are prerequisite steps in Thy-1 receptor cap formation. 相似文献
23.
J Li R C Eisensmith T Wang W H Lo S Z Huang Y T Zeng L F Yuan S R Liu S L Woo 《Genomics》1992,13(3):894-895
Three novel missense mutations have been identified in the phenylalanine hydroxylase (PAH) genes of Chinese individuals afflicted with various degrees of phenylketonuria (PKU). A T-to-C transition was observed in exon 5 of the gene, resulting in the substitution of Phe161 by Ser161. Two substitutions, G-to-T and T-to-G, were observed in exon 7, resulting in the substitution of Gly247 by Val247 and Leu255 by Val255, respectively. Expression analysis demonstrated that these mutant proteins produced between 0 and 15% of normal PAH enzyme activity. Population screening of a Chinese sample population indicates that these mutations are quite rare, together accounting for only about 4% of all PKU alleles among the Chinese. The P161S and G247V mutations were each present on a single PAH RFLP haplotype 4 chromosome in patients form Northern China, while the L255V mutation was present on chromosomes of both haplotypes 18 and 21 in patients from Southern China. These results suggest that the remaining 30% of uncharacterized PKU alleles in the Chinese population may bear a large number of relatively rare PAH mutations. 相似文献
24.
D C Lo 《Current opinion in neurobiology》1992,2(3):336-340
Our understanding of the molecular nature of neurotrophic interactions has been greatly enhanced by the recent isolation and characterization of several new neurotrophic factors and their receptors. Neurotrophic factors have been found to be regulated by neuronal activity in the central nervous system, and may be involved in activity-dependent processes throughout development and maturity. 相似文献
25.
人体和动物模型的体表物理信息地形图的研究 总被引:1,自引:0,他引:1
对人体头面、躯干、四肢、耳廓各局部几十个及整个人体等体表部位正、背面等210个部位进行超微弱冷光和温度测量,输入电子计算机,经特殊的自编程序处理,获得十分清晰的,由3000多数据构成的各个局部或人体整体的冷光和温度地形图。 对家兔左、右耳廓、胸腹部、背部都分别观察32个部位的冷光与体表温度,经计算机分析处理,每观察区域获得约由2000个数据构成的精确的冷光、温度地形分市图。并可见不同生理、病理状态及不同病程家兔体表冷光、温度等地形图呈有规律的改变。 此外,我们还编制了以体表左右相应对称部位差值为分析数据进行地形图分析的程序,用以人体和动物体表物理信息对称规律的研究。 本工作以图形的形式显示物理参量在体表的广泛的分布规律,以揭示机体内部的不同生理、病理状态。本方法定位准确、直观醒目,为研究体表信息及机体生命活动规律提供了与逐点直接测量方法相互补充的有益的新手段。 相似文献
26.
27.
In the current study the argyrophil staining technique for NOR proteins (Ag-NORs) has been performed on cases of different endometrial lesions, trying to find an aid in differentiating atypical hyperplasia from well differentiated carcinoma in biopsy specimens. We conclude that the Ag-NOR count, even though in endometrial carcinoma is significantly exceeding that of atypical hyperplastic endometrium, could be a misleading discriminator, because of a wide overlap of values in individual cases. 相似文献
28.
The TIS11 primary response gene is a member of a gene family that encodes proteins with a highly conserved sequence containing an unusual Cys-His repeat. 总被引:8,自引:1,他引:7 下载免费PDF全文
B C Varnum Q F Ma T H Chi B Fletcher H R Herschman 《Molecular and cellular biology》1991,11(3):1754-1758
The TIS11 primary response gene is rapidly and transiently induced by both 12-O-tetradecanoylphorbol-13-acetate and growth factors. The predicted TIS11 protein contains a 6-amino-acid repeat, YKTELC. We cloned two additional cDNAs, TIS11b and TIS11d, that contain the YKTELC sequence. TIS11, TIS11b, and TIS11d proteins share a 67-amino-acid region of sequence similarity that includes the YKTELC repeat and two cysteine-histidine containing repeats. TIS11 gene family members are not coordinately expressed: (i) unlike TIS11, the TIS11b and TIS11d mRNAs are detectable in quiescent Swiss 3T3 cells and are not dramatically induced by 12-O-tetradecanoylphorbol-13-acetate; (ii) cycloheximide superinduction does not occur for TIS11b and TIS11d; and (iii) unlike TIS11, TIS11b expression is extinguished in PC12 pheochromocytoma cells. 相似文献
29.
The changes in met-enkephalin and beta-endorphin contents in the pituitary in PTU-induced hypothyroidism were studied in the rat. After 2 weeks of PTU-treatment, both IR-met-enkephalin and IR-beta-endorphin contents in the pituitary were significantly reduced. Gel filtration chromatography followed by radioimmunoassay showed that the immunoactivities in the peaks of precursors, met-enkephalin, beta-lipotropin and beta-endorphin were all lower in the pituitaries from the PTU-treated rats. In another experiment, some of the PTU-treated rats were injected daily with 500 micrograms T3/kg b.w. In the hypothyroid rats, IR-met-enkephalin and IR-beta-endorphin contents were decreased in both the anterior and neurointermediate lobes. Only the changes in the anterior lobe were reversed by T3 treatment. In conclusion, while the effects on the anterior lobe are probably due to a deficiency in thyroid hormones, the mechanism for the decrease of opioid peptide contents in the neurointermediate lobe is still unclear. 相似文献
30.