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461.
During the long starvation period (November to June) of the lizard (Varanus exanthematicus), pancreatic B cells undergo profound modification. The degeneration of beta granules observed in electron microscopy appears correlated with the diminution of the immunoreactive insulin-like content of the pancreas. The analogy between the phenomena observed here and those reported in animals treated with alloxan is discussed. 相似文献
462.
463.
A M Mileo M Fanuele F Battaglia G Scambia C Benedetti-Panici E Mattei S Mancuso A Delpino 《The International journal of biological markers》1992,7(2):114-118
The HER-2/neu oncogene (a member of the Erb-like oncogene family) is distinct from but closely related to the c-erb B gene which encodes the epidermal growth factor receptor (EGFr). HER-2/neu gene amplification was found in a large number of mammary carcinomas and there was a strong correlation between this phenomenon and poor prognosis. In our study HER-2/neu oncogene expression was determined in 16 malignant ovarian tumors, 2 ovarian lymphomas and 5 normal ovaries. The HER-2/neu gene was found both in normal ovaries and malignant tumors, without any apparent difference among the various histological types. In all the specimens examined, HER-2/neu expression did not seem to be related to EGF binding capacity. 相似文献
464.
465.
Bullous pemphigoid antigen (BPAG1): cDNA cloning and mapping of the gene to the short arm of human chromosome 6 总被引:6,自引:0,他引:6
Bullous pemphigoid antigen (BPAG1), an integral component of the cutaneous basement membrane zone, serves as autoantigen in a blistering disease, bullous pemphigoid. In this study, we have generated cDNAs corresponding to human BPAG1 sequences. Two cDNAs, a 0.45-kb PCR product synthesized with human keratinocyte RNA as template and a 2.2-kb cDNA isolated from human keratinocyte lambda gt11 library, were utilized for chromosomal in situ hybridizations to establish the genomic location of the BPAG1 gene. Metaphase chromosomes of phytohemagglutinin-stimulated human peripheral blood leukocytes were examined by hybridizations with 3H-labeled cDNAs, and the chromosomes were identified by R-banding (fluorochrome-photolysis-Giemsa method). The results indicated that the human BPAG1 gene is at locus 6p11-6p12. This conclusion was supported by hybridizations with a panel of human X rodent hybrid cell DNA, which indicated concordance with human chromosome 6. Because different genes encoding human basement membrane components have been mapped previously to chromosomes other than 6, the results further indicate that human basement membrane zone genes are widely dispersed within the human genome. 相似文献
466.
Perrine Malzac Marie-Geneviève Mattei Jean Thibault Gilles Bruneau 《Human genetics》1996,97(3):359-361
Using a rat histidine decarboxylase (HDC) cDNA probe, we have mapped the HDC gene by in situ hybridization to the ql5–q2l region of human chromosom e15 and to the E5-G region of murine chromosome 2. These localizations strengthen a syntenic group conserved between human chromosome 15 and mouse chromosome 2. The localization of the HDC gene on the human chromosome 15 map shows that it is not included within the Prader-Willi Syndrome region (PWCR). 相似文献
467.
P. Laurent P. Clerc M. -G. Mattei P. Forgez X. Dumont P. Ferrara D. Caput W. Rostene 《Mammalian genome》1994,5(5):303-306
Neurotensin is a tridecapeptide that plays several neurotransmitter or neuromodulatory roles both in the central nervous system and in the periphery. These actions are mediated by a high-affinity receptor (Ntsr). Both rat and human cDNAs encoding high-affinity receptors have been recently cloned. The availability of Ntsr probes allowed us to localize the corresponding genes on the mouse and human chromosomes. The present data demonstrate that the Ntsr gene is assigned to the H region of the mouse Chromosome (Chr) 2 and to the long arm of the human Chr 20. 相似文献
468.
469.
The walls of lobules in the testis of Ophidion sp. are composed of Scrtoli cells and young germinal cells (spermatogonia and spermatocytes). Spermatocytes are linked by cytoplasmic bridges. The associations of Sertoli cells and spermatocytes constitute true cysts. Meiosis takes place in the cysts. When meiosis is complete, cysts open. Spermatids are released into the lumen of the lobules and the cyloplasmic bridges break down. Spermiogenesis occurs in the lumen. Spermatids at various levels of spermiogenesis are then mixed with ripe spermatozoa. In teleosts we thus recognize two types of spermatogenesis: a cystic type where spermatogenesis is completed within cysts, and leads to synchronous development of germ-cells; and a semi-cystic type, where spermatogenesis occurs partly outside cysts. This may produce asynchronous spermatogenesis. 相似文献
470.
Summary There were 18 individuals found to have a constitutional chromosome fragility causing an increase in break frequency. For each chromosome the breakpoint is always the same, whether it involves chromosomes from the same person, the same family, or different families. The fragile points are bands 10q24, 12q13, 16q21, 17p12, and Xq27. Autosomal constitutional fragility does not seem to have a phenotypic correspondence. They were found mostly in parents of children with chromosomal abnormalities or in couples with a history of repeated spontaneous abortions which permits one to raise the possibility of an interchromosomal effect. The six constitutional chromosomal fragilities of the X chromosome had in common the association of mental deficiency, delayed speech, and large malformed ears. The break points in constitutional chromosomal fragility were compared to those of spontaneous breaks in vitro, to those induced by X-rays, and to those in Fanconi's anemia. The theoretical consequences of these structural abnormalities are discussed as well as what to do about them when they are found.This study was supported by I.N.S.E.R.M. (C.R.L. No. 7510424).Text of the communication presented at the Symposium on Medical Genetics, Debrecen-Hajduszoboszlo, Hungary, 27–29 april 1976. 相似文献