Summary We have studied the frequency of trisomics in newly formed zygotes and the proportion of trisomics, k, coming from consanguineous marriages by assuming that recessive genes at a single locus or multiple loci are responsible for the induction of nondisjunction. For mitotic nondisjunction, the value of k increases as the magnitude of consanguinity of the parents increases, but the opposite relationship holds for meiotic nondisjunction. Therefore, it is important to distinguish mitotic and meiotic types in the genetic study of nondisjunction. This seems to be one of the simples tests for detecting the genetic control of nondisjunction. 相似文献
A procedure for the simultaneous preparation of S-sulfo-l-cysteine and l-alanine 3-sulfinic acid is described. The method is based on the quantitative reaction between sulfite and S-(2-amino-2-carboxyethylsulfonyl)-l-cysteine. The yield was 95% for S-sulfo-l-cysteine and 91% for l-alanine 3-sulfinic acid. The reaction was also applied to the quantitative determination of sulfite in biological materials. In this procedure, sulfite reacts with S-(2-amino-2-carboxyethylsulfonyl)-l-cysteine. Separation of the reaction product, S-sulfo-l-cysteine, is done by ion-exchange fractionation, and it is determined with acid ninhydrin reagent 2 (M. K. Gaitonde, 1967, Biochem. J.104, 627–663). The recovery was 96.8 ± 0.3%. 相似文献
The effect of fatty acids and monoglycerides on barrier properties of liposomal membranes prepared from egg phosphatidylcholine was investigated. The incorporation of these lipids as liposomal membrane components induced the alteration of the permeability to less permeable liposomally entrapped drugs, sulfanilic acid and procainamide ethobromide (PAEB). Monoolein caused greatly increased permeability of both drugs and unsaturated fatty acids markedly enhanced the release rate of PAEB, while saturated fatty acids caused a small increase in the release rate.Electron spin resonance (ESR) investigation with 5-nitroxide stearic acid showed that fatty acids disordered the hydrophobic region of the lipid bilayer and the disordering effect of unsaturated fatty acids was greater than that of saturated ones. It was demonstrated that the incorporated fatty acids and monoglycerides interacted with the polar region of the membranes by ESR study with cholestane label and 1H-NMR study. These results indicated that the increase in the membrane permeability caused by fatty acids and monoglycerides associated with the disorder in the membranes' interior and the interaction of the incorporated lipid with the polar head group of phospholipid. 相似文献
814 hemoglobin samples from Korean cattle were investigated by starch gel electrophoresis for the detection of hemoglobin variants. A new variant of cattle hemoglobin, called Hb, H, was recognized. It has a slower rate of migration than Hb A. Hemoglobin types from 814 Korean cattle were as follows: 652 of Hb AA type (80.1 %), 133 of Hb AB (16.4 %), 12 of Hb AC (1.5 %), 9 of Hb BB (1.1 %), 2 of Hb BC (0.2 %), 4 of Hb AH (0.5 %), 1 of Hb CH (0.1 %), 1 of Hb HH (0.1 %). These figures correspond to the frequencies: HbA = 0.893, HbB = 0.093, Hbc =0.009, HbH = 0.004. Gene frequencies at the Hb locus in Korean cattle were compared among six population from different provinces. Generally, high frequencies of HbA were observed in each province. 相似文献
Based on the Fisher-Muller theory of the evolution of recombination, an argument can be constructed predicting that a recessive allele favoring recombination will be favored, if there are either favorable or deleterious mutants occurring at other loci. In this case there is no clear distinction between individual and group selection. Computer simulation of populations segregating for recessive or dominant recombination alleles showed selection favoring recombination, except in the case of a dominant recombination allele with deleterious background mutants. The relationship of this work to parallel investigations by Williams and by Strobeck, Maynard Smith, and Charlesworth is explored. All seem to rely on the same phenomenon. There seems no reason to assume that the evolution of recombination must have occurred by group selection. 相似文献
The effect of human platelet functions of 9,11-dithio analogues of prostaglandin endoperoxide was investigated. Methyl (5z,9α,11α,13e,15S)-9,11-epidithio-15-hydroxyprosta- 5,13-dienoate induced platelet aggregation, while the 9β,11β-epimer was inactive. The platelet aggregation caused by the 9α,11α-dithio analogue was associated with serotonin release from platelets, and was inhibited by methyl ester of prostaglandin I2 (prostacyclin) but not by indomethacin. 相似文献
Enzyme(s) capable of decomposing N-acetylglucosaminyl ribitol teichoic acid prepared from the cell wall of Staphylococcus aureus FDA 209 P was obtained from the culture supernatant of a gram-negative, rod-shaped, spore-forming soil bacterium. Properties of the bacterium were very similar to those of Bacillus circulans. 相似文献
Urban waterlogging stems from coverage with impervious surfaces and increasing rainfall intensity from climate change and variability, meaning that storm water cannot readily infiltrate the ground and excessive surface runoff leads to urban flooding. To reduce related environmental and safety risks, rainfall and groundwater level research was carried out in Kyoto Prefecture with two rain gardens (RG1 and RG2) to investigate flood mitigation functions using a tank model. During the 134 days of monitoring from July 14, 2017, to November 25, 2017, RG1 had seven overflow events with an average runoff control ratio of 63.94%, and RG2 had one event with a ratio of 95.97%. The RG1 tank model (two stages) showed that initial storage for the first and second depths was 6.912?×?10?11 and 0 mm, respectively. The heights of the discharge holes were 20.857 and 0.784 mm for the first stage and 0.659 mm for the second stage, and the discharge hole coefficients were 0.529 and 0.002 for the first stage and 0.004 for the second stage. The results showed that RG1 had penetration hole coefficients of 0.138 (first stage) and 0.254 (second stage), with a water balance error of 0.017 (<?0.02) and a Nash–Sutcliffe efficiency coefficient of 0.922, indicating better reliability and quality than RG2 with the one-stage tank model. Peak flow simulation for mitigation showed that RG1 had a high overflow control ratio (mitigation time 2 h for instant rainfall of 100 mm/h), and can therefore be considered appropriate for other urban areas of Japan.
Landscape and Ecological Engineering - In the original publication of the article, Figure 1 was published incorrectly. The correct figure is given below. 相似文献