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251.
L J Valentijn F Baas R A Wolterman J E Hoogendijk N H van den Bosch I Zorn A W Gabre?ls-Festen M de Visser P A Bolhuis 《Nature genetics》1992,2(4):288-291
We have investigated the peripheral myelin protein gene, PMP-22, in a family with Charcot-Marie-Tooth disease type 1A (CMT1A). The DNA duplication commonly found in CMT1A was absent in this family, but strong linkage existed between the disease and the CMT1A marker VAW409R3 on chromosome 17p11.2. We found a point mutation in PMP-22 which was completely linked with the disease. The mutation, a proline for leucine substitution in the first putative transmembrane domain, is identical to that recently found in the Trembler-J mouse. The presence of this PMP-22 defect in this CMT1A family and the location of PMP-22 within the DNA duplication associated with CMT1A suggest that both structural alteration and overexpression of PMP-22 may lead to the disease. 相似文献
252.
J. K. Buitelaar H. van Engeland C. H. de Kogel H. de Vries J. A. R. A. M. van Hooff J. M. van Ree 《Cellular and molecular life sciences : CMLS》1992,48(4):391-394
When charting the structure of the social behavior of autistic children by means of an ethologically analyzed playroom session, deficits appeared in the reciprocity of eye-contact and in the location of verbal initiatives. These deficits in social behavior were beneficially influenced by treatment with the adrenocorticotrophic hormone (4–9) analog ORG 2766. 相似文献
253.
254.
Summary Increase of the ionic strength inhibits the catalytic activity of the mitochondrial MDH, reduces substrate inhibition and decreases the affinity of substrates for the enzyme.This work was supported by a grant from the Conselho Nacional de Desenvolvimento Tecnológico (CNPq), Brazil. 相似文献
255.
Isocaloric and isovolemic amounts of protein (casein), fat (intralipid) and carbohydrate (saccharose) and an isovolemic control solution of water were administered intragastrically to conscious rats. The plasma CCK levels, determined by a sensitive and specific radioimmunoassay, showed an increment of 6.3 +/- 0.6, 2.7 +/- 0.5, 1.7 +/- 0.4 and -0.9 +/- 0.4 pM, respectively (basal value 2.5 +/- 0.3 pM). The threshold increment of plasma CCK to stimulate pancreatic enzyme secretion by exogenous CCK was found to be 1.5 pM. It is therefore concluded that casein is a potent stimulus for CCK secretion and pancreatic secretion, but that fat and even carbohydrate, although less potent, also produce a CCK increment above the threshold for pancreatic secretion. 相似文献
256.
257.
M H de Bruijn 《Nature》1983,304(5923):234-241
The sequence of a 4,869 base-pair fragment of Drosophila melanogaster mitochondrial DNA is presented. It contains genes for cytochrome oxidase subunits I, II and III, ATPase subunit 6 and six tRNAs together with two unassigned reading frames. The gene organization differs from that of mammalian mitochondrial DNAs. Evidence is provided for a genetic code in which AGA codes for serine and the quadruplet ATAA is used in initiation of translation. 相似文献
258.
Germline mosaicism and Duchenne muscular dystrophy mutations 总被引:12,自引:0,他引:12
E Bakker C Van Broeckhoven E J Bonten M J van de Vooren H Veenema W Van Hul G J Van Ommen A Vandenberghe P L Pearson 《Nature》1987,329(6139):554-556
Duchenne muscular dystrophy (DMD) is a severe X-linked neuromuscular disease with an incidence of approximately 1 in 3,500 newborn boys. The DMD locus has a high mutation frequency: one third of the cases is thought to result from a new mutation. Linkage studies using probes to detect restriction fragment length polymorphisms and DNA deletion studies have greatly improved DMD carrier detection and prenatal diagnosis. Here we report on two families in which a pERT87 (DXS164) deletion was transmitted to more than one offspring by women who showed no evidence for the mutation in their own somatic (white blood) cells. We also show that the deletion in both siblings in one of the families is identical, indicating that the deletion must have occurred during mitosis in early germline proliferation, leading to a germline mosaicism. This phenomenon may turn out to be a major factor contributing to the induction of DMD mutations, and has important implications for the counselling of DMD families. 相似文献
259.
Cholera toxin genes: nucleotide sequence, deletion analysis and vaccine development 总被引:25,自引:0,他引:25
Nucleotide sequence and deletion analysis have been used to identify the regulatory and coding sequences comprising the cholera toxin operon (ctx). Incorporation of defined in vitro-generated ctx deletion mutations into Vibrio cholerae by in vivo genetic recombination produced strains which have practical value in cholera vaccine development. 相似文献
260.
J de Koning A M Tijssen J A van Dieten T R Koiter G A Schuiling G P van Rees 《Experientia》1986,42(1):60-62
The patterns of LH secretion during constant stimulation of the pituitary glands of estradiol-treated ovariectomized rats with a maximally stimulating amount of LH-RH in vivo and in vitro correspond with each other qualitatively and quantitatively. In vitro the changes with time of the LH secretion rate are somewhat retarded, especially the occurrence of desensitization. 相似文献