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Jessica E. Hoogendijk Gerard W. Hensels Ina Zorn Linda Valentijn Emiel A. M. Janssen Marianne de Visser David F. Barker Bram W. Ongerboer de Visser Frank Baas Pieter A. Bolhuis 《Human genetics》1991,88(2):215-218
Summary Recently, it has been shown that Charcot-Marie-Tooth disease type 1a (CMT1a) is linked with a duplication of a DNA segment that is detected by probe VAW409R3, and that is located on chromosome 17p11.2. Here, we show that this duplication also contains VAW412R3a, but not A10-41 and EW503. Accounting for the duplication in recombination analysis, we found recombinants between CMT1a and EW301 and EW502, but not with A10-41, VAW409R3, and VAW412R3. Using pulsed-field gel electrophoresis analysis, we estimated the minimal size of the duplicated region in CMT1a patients to be 1100 kb. 相似文献
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The serum unsaturated vitamin B12-binding capacity (UBBC), unsaturated transcobalamin (UTC) I, UTC II, UTC III levels, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase activities and bilirubin concentration were estimated in 61 patients with liver diseases (31 with hepatoma, 30 with viral hepatitis). The levels of serum cobalamin, UTC I, UTC III, UBBC, alanine and aspartate aminotransferases, and bilirubin were raised in both hepatoma and viral hepatitis patients. Serum UTC II was reduced in both conditions. Alkaline phosphatase activity was significantly increased in hepatoma. Four significant correlations were observed among these parameters in the hepatoma patients while only one significant correlation was observed in viral hepatitis. 相似文献
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Dr. Gerard J. McGarrity Lindsay Gamon Theodor Steiner Joseph Tully Hitoshi Kotani 《Current microbiology》1985,12(2):107-112
Uridine phosphorylase activity has been used to detect mycoplasmas in cell cultures by measuring formation of14C-uracil from14C-uridine. In this report we show that all species ofMycoplasma, Acholeplasma, andUreaplasma tested exhibited uridine phorphorylase activity. Among the genusSpiroplasma, serogroups I-1, I-3, I-5, I-7, I-8, IV, XIII, and XIV lacked uridine phosphorylase activity.Present address: Ciba-Geigy, Basel, Switzerland. 相似文献
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Summary We have cloned the hisH tyrA wild-type genes of Bacillus subtilis with the aid of the chimeric plasmid pBJ194, which replicates both in B. subtilis and Escherichia coli. Primary cloning was done in E. coli. The original E. coli clone, carrying the recombinant plasmid (pGR1) which complements hisH tyrA mutants of B. subtilis, was selected directly from a mixture of plated E. coli clones by replicaplating these clones onto minimal agar plates without tyrosine spread just before with competent B. subtilis cells. After overnight incubation clusters of small colonies had developed exclusively in the E. coli [pGR1] colony prints.The Tyr+ minicolonies were shown to be B. subtilis carrying pGR1 because (i) their appearance depended linearly on the number of B. subtilis cells plated, (ii) they produced extracellular protease and amylase and (iii) plasmids could be reisolated from the minicolonies and used to transform B. subtilis recE4 tyrA1 both to Cmr and Tyr+.Plasmid pGR1 transfer through replica plating was compared with plasmid transfer in liquid. Both systems depended on transformable B. subtilis strains and were sensitive to DNAseI. However, whereas integration of the tyrA
+ gene into the chromosome and concomittant loss of plasmids occurred frequently during regular plasmid transformation of Rec+
B. subtilis, this was a rare event during plasmid transfer through replica plating. 相似文献
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ELECTRON MICROSCOPIC OBSERVATIONS OF RAT AND MOUSE CEREBELLUM IN TISSUE CULTURE 总被引:12,自引:8,他引:4 下载免费PDF全文
Closely ordered stages of myelin formation in cultures of newborn rat and mouse cerebellum, selected by direct light microscopy, were studied with the electron microscope. Electron micrographs of these cultures reveal the presence of neurons, axons, neuroglia, microglia, and ependymal cells. The appearance of the neuron is identical to that previously described in vivo. The neuroglial cell has long, branching processes, and its cytoplasm is characterized by packets of long, narrow fibrils. During myelin formation, a glial cell process surrounds the axon. This process may form an internal mesaxon and may spiral for several turns around the axon. Other glial cell processes may interdigitate with or overlay the innermost process to contribute to the multilamellated structure. The glial processes flatten and the cytoplasmic surfaces of the cell membrane come into contact to form the lamellae of the myelin sheath. These adhesions may be temporarily incomplete as evidenced by sequestered islands of glial cytoplasm among the myelin lamellae. Ultimately, a compact, apparently spiral, myelin sheath is formed. These findings are discussed in relation to in vivo central myelin formation. 相似文献