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101.
Nielsen Johannes Vetner Max Holm Vagn Askjær Svend Aage Reske-Nielsen Edith 《Human genetics》1977,38(3):357-362
Summary A case of Meckel or Gruber syndrome is reported, together with a survey of the relevant literature of recent years (1971–1977), in reference to a probably autosomal recessive inheritance of this malformation. 相似文献
102.
Johannis P. Kamerling Gerrit J. Gerwig Johannes F.G. Vliegenthart Marinus Duran Dirk Ketting Sybe K. Wadman 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1977,143(2):117-123
The separation of the enantiomers of lactic and glyceric acids can be achieved by capillary gas chromatography on SP-1000 using the corresponding O-acetylated menthyl esters. The structures of the derivatives were proved by proton magnetic resonance spectroscopy and mass spectrometry. The method has been used for the determination of the absolute configurations of lactic and glyceric acids isolated from serum and urine from different patients. 相似文献
103.
Microbotryum silenes-inflatae (DC) G. Deml & Oberw. and Microbotryum violaceoirregulare (Brandenburger & Schwinn) G. Deml & Oberw., both parasitic in the anthers of Silene vulgaris (Moench) Garcke, are compared by their morphology, karyology, and some cultural characteristics. The infection of their hosts is similar in both species, but causes different sizes of the flowers and different color of the spore mass. The teliospore initials of that smuts are produced in dikaryotic sporogenous hyphae. During gelatinization of the hyphal coat, surface ornamentations on the teliospores are formed. Mature teliospores are monokaryotic, and presumably diploid, reticulate in Microbotryum silenes-inflatae and echinulate in M. violaceo-irregulare. Teliospores of both species germinate without a resting periode. Germination results in a commonly three-celled promycelium, which in M. silenes-inflatae separates from the producing teliospore, while in M. violaceo-irregulare it remains on the teliospore during basidiospore formation. The basidiospores are monokaryotic and propagate by budding. Monokaryotic strains were isolated and characterized by standard yeast identification tests and by some enzymatic activities on solid media. While no differences in the enzymatic activities can be found, the species differ in their utilization of carbon sources. 相似文献
104.
105.
Electrophoretic variation characterized by the presence (ES-5B+) or absence (ES-5B–) of esterase-5B in the plasma of the house mouse has been observed. It is suggested that the expression of esterase-5B is controlled by an autosomal locus, Esr, linked to Ldr-1 on chromosome 6, in addition to the presumptive structural locus Es-5, which is located on chromosome 8. A gene order of Lyt-3-Esr-Ldr-1 was determined by two crosses.Supported by the Deutsche Forschungsgemeinschaft (SFB 46).This is communication No. 33 of a research program devoted to the investigation of cellular distribution and genetics of nonspecific esterases. 相似文献
106.
Oocyte nuclei of the dipteran insect Heteropeza pygmaea display swift pulsating movements during in vitro follicle formation in the ovaries. Low doses of cytochalasin B (CB) completely inhibit the nuclear movements within a few minutes and cause the nuclei to assume spherical shapes. If the drug is removed, nuclear pulsation is resumed within 5–10 min. Phalloidin and colchicine do not affect the nuclear movements. Actin is shown by indirect immunofluorescence microscopy to be present in considerable amounts all over the cytoplasm of the oocytes. It is concluded that microfilaments are responsible for pulsation of the oocyte nuclei, whereas microtubules are not involved. 相似文献
107.
108.
Anke Burmester Anke Wöstemeyer Jose Arnau Johannes Wöstemeyer 《Molecular & general genetics : MGG》1992,235(2-3):166-172
Summary A series of new vectors for the model zygomycete Absidia glauca was constructed on the basis of the structural neomycin resistance (Neor) gene controlled by the promoter of the gene for elongation factor 1 (TEF). In order to select for transformed colonies with a stable Neor phenotype, spores from primary transformants were pooled and grown for two sporulation cycles under non-selective conditions. Southern blot analysis of DNA from single spore isolates originating from independent transformant pools allowed the identification of two autonomously replicating plasmids. Retransformation of Escherichia coli and restriction analysis of the two plasmids provided evidence for spontaneous in vivo insertion of a new DNA element (SEG1) from the A. glauca genome. The inserted regions in both plasmids are essentially identical and do not represent repetitive DNA. Compared with other autonomously replicating vectors, these SEG1-containing plasmids are mitotically extremely stable and are passed on to the vegetative spore progeny of a retransformed A. glauca strain. We assume that SEG1 contains structural elements involved in partitioning and stable segregation of plasmids. For the construction of stable transformants of A. glauca, the SEG1 element may be regarded as a major breakthrough, because stabilization of transformed genetic traits by integration is difficult to achieve in all mucoraceous fungi and all known replicating plasmids are mitotically unstable. 相似文献
109.
PalZ - Hyperostotic fish bones from the presumable Pliocene phosphate-bearing deposits along Lake Manyara, Tanzania, are described. In contrast to marine occurrences of this kind, the pathological... 相似文献
110.