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21.
Lectin binding patterns in normal human endometrium were examined by light and electron microscopy using seven different lectins (ConA, WGA, RCA, PNA, UEA-1, DBA, and SBA). For light microscopic observations, criteria based on the incidence and intensity of cells positive for the lectin staining were adopted to evaluate the different staining patterns of the proliferative and secretory endometria obtained by the avidin-biotin-peroxidase complex (ABC) technique. At the light microscopic level, ConA, WGA, and RCA stained endometrial glandular cells in both phases. The number of PNA-positive cells with the binding sites entirely limited to the apical surface tended to be reduced slightly in the secretory phase. UEA-1 weakly stained the apical surface of glandular cells in the proliferative phase but not in the secretory phase. Among the lectins used in this study, DBA and SBA displayed remarkable changes between the phases. That is, in the proliferative phase they produced only a faint or slight positive stain at the apical surface, but the incidence and intensity of DBA- and the SBA-positive glandular cells increased in the secretory phase. By electron microscopy, the reaction product of ConA was observed in the plasma membrane, endoplasmic reticulum, nuclear envelope, and the Golgi apparatus, and the binding sites of RCA and DBA were observed in the plasma and Golgi membranes. Between both phases, the reactivity of ConA and RCA showed almost no change. However, the secretory endometrial cells containing the DBA-positive Golgi apparatus were markedly increased in number compared with the proliferative ones bearing the lectin-positive organelles.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
22.
Summary Characteristics of the enantioselective hydrolysis of the acetic ester of 4-hydroxy-3-methyl-2-(2-propynyl)-2-cyclopentenone (HMPC) by Arthrobacter lipase were investigated in a water/oil biphasic reaction mixture. Kinetic studies revealed that the strict enantioselectivity was entirely due to a difference in the catalytic constants for the enantiomeric substrates and that (S)-HMPC acetate acted as a competitive inhibitor. The comparison of enantioselectivity for the acetates of HMPC analogues indicated that hydrophobic substituents in the HMPC molecule were essential for the strict enantioselectivity.Biological preparation of an optically active alcohol. Part II  相似文献   
23.
In most species of lepidopteran insects, anteroposterior rows formed by scales are arranged at regular intervals in the adult wing; within each row two kinds of scales are alternately arranged. To investigate the cellular basis for the scale arrangement pattern, we examined cell arrangement in the epidermal monolayer of the pupal wing of a small white cabbage butterfly, Pieris rapae , by scanning electron microscopy and light microscopy.
The arrangement of scale precursor cells, closely resembling that of scales in the adult wing, was observed in the wing epidermis of the early pupa. Scale precursor cells are proximodistally elongated and form anteroposterior rows. Within a row two kinds of scale precursor cells are nearly alternately arranged, which is not so precise as the alternation of scales in the adult wing. Individual rows of scale precursor cells are separated by rows of single or double undifferentiated general epidermal cells. Occasionally, arrangement abnormalities occur both in the adult and the pupal wing. The cellular basis for the regular spacing of scale rows is discussed.  相似文献   
24.
We have developed a radioimmunoassay (RIA) for nonenzymatically glycated serum proteins. The polyclonal antibodies prepared against reduced glycated human albumin were specific for the glucitollysine residues of serum proteins. Serum proteins from diabetic patients (n = 25) contained 5.3 +/- 2.8 nmoles of glucitollysine/mg protein, compared to 2.0 +/- 0.2 in controls (n = 20). The intra- and inter-assay variables were 3.2-6.2% and 4.4-8.6%, respectively. Results from this assay procedure correlated well with those from the boronate affinity chromatography procedure (r = 0.94; P less than 0.001). The data suggested that diabetic serum proteins contained at least 2.5 times as much immunochemically detectable glucitollysine residures as normal serum proteins after reduction of the proteins with sodium borohydride.  相似文献   
25.
Summary The XmnI genotype at the apolipoprotein A-I locus was heterozygous in a boy with partial deletion of the long arm of chromosome 11, del(11)(q23.3qter). The apolipoprotein A-I gene, previously assigned to chromosome region 11q23q24, has been more specifically localized to 11q23 by excluding the region 11q24qter.  相似文献   
26.
The effects of different light regimes on the survival, growth and morphology ofQuercus serrata seedlings were studied in canopies ofMiscanthus sinensis. The seedlings of various ages (0–3 yr) were grown in three light regimes: under a denseM. sinensis canopy (TG plot) receiving 2.5%–8.7% of full sunlight, under a relatively sparse canopy (SG plot) receiving 3.8%–16.1% of light and in an adjacent open site (NG plot). There was a little difference in the survival ofQ. serrata seedlings among the three plots. Height and diameter of stem and total leaf area of the seedlings were significantly lower in the shadier plots. However, the first (bottom) flush of the stem was significantly longer in the TG plot than in the NG and SG plots. Total dry weights of individual 1- and 2-yr-oldQ. serrata seedlings in the TG plot were reduced to about one-twelfth of those in the NG plot. Although the relative proportion in dry weight of each organ did not differ significantly among the plots, leaf area ratio, specific leaf area and stem height per unit dry weight were significantly higher in shadier plots. The leaf area per unit stem height was increased considerably in the sunnier plots.  相似文献   
27.
Common DNA fragments of the α-globin gene were observed in five races of adult common carp: mirror, scaly-German, Yamato-Suwa, Yamato-Saku, and Yamato-hybrid carp. There were different hybridization patterns between the Japanese carp and the German carp. Three to four DNA fragments hybridized with α-globin and indicated polymorphysim in the globin gene of carp.

Zusammenfassung


DNA-Homologie des α-Globin-Genes bei fünf Karpfenrassen, Cyprinus carpio
Identische Fragmente des α-Globin-Genes wurden bei fünf Rassen des adulten gemeinen Karpfens (Spiegeikarpfen, deutscher Schuppenkarpfen, Yamato-Suwa-, Yamato-Saku-und Yamato-Hybrid-karpfen) gefunden. Es gab verschiedene Hybridisationsmuster zwischen dem japanischen und dem deutschen Karpfen. Drei bis vier DNA-Fragmente hybridisierten mit α-Globin und wiesen auf einen Polymorphismus des Globingenes des Karpfens hin.

Résumé


Homologie de DNA dans le gène d'α-globine chez cinq races de carpe, Cyprinus carpio
Des fragments communs de DNA dans des gènes d'α-globine ont été observés chez cinq races de carpe commune adulte: carpe miroir, allemande écailleuse, Yamato-Suwa, Yamato-Saku et Yamato-hybride. Il existait différentes combinaisons d'hybridation entre la carpe allemande et la carpe japonaise. Trois à quatre fragments de DNA hybridisaient avec l'α-globine et indiquaient un polymorphisme dans les gènes de globine de carpe.  相似文献   
28.
The possibility of involvement of calcium ions in the hatching of Schistosoma mansoni eggs in water is described. The hatching of S. mansoni eggs under low osmotic pressure was partially inhibited by EGTA (5 mM), lanthanum chloride (1-5 mM), and ruthenium red (0.1-1 mM). The reagents used in these experiments were not toxic to the eggs however, because miracidia hatched normally when the reagents were removed.  相似文献   
29.
We showed that the surface charge density of protoplasts canbe estimated by the 9-aminoacridine method. The estimated surfacecharge density of the protoplasts isolated from elongating regionsof Vigna mungo root was – 39 ? 8 mC/m2. The negative surfacecharge density increased when protoplasts were treated withglutaraldehyde or when EDTA was added to the protoplast suspensionmedium. These results support the validity of our estimationof the surface charge density of protoplasts by the 9-aminoacridinemethod. The concentration of amino groups at the surface ofthe protoplasts was estimated to be 34 mC/m2. (Received June 19, 1987; Accepted April 11, 1988)  相似文献   
30.
The molybdenum-iron component of nitrogenase (Mo-Fe component)was purified from soybean nodule bacteroids and antibody wasraised against it in rabbits. Antibody raised against the 53kDa polypeptide which was the major protein in the Mo-Fe componentfraction of soybean nitrogenase was confirmed to be specificto the nitrogenase by immunodiffusion and immunotitration. Thenitrogenase from root nodules of Elaeagnus pungens cross-reactedwith the antibody and appeared from the results of the immunodiffusionto be partially identical to soybean nitrogenase. Using the antibody, we examined intracellular localization ofnitrogenase in root nodules of Elaeagnus pungens, in which Frankiais present as a symbiont, by immuno-gold labelling. Thin sectionsof nodules of Elaeagnus pungens were first treated with anti-nitrogenasespecific antibody and then with colloidal gold-protein A asa marker. The gold particles were observed to be concentratedin the vesicles of the endophyte Frankia. This provides strongsupport for the existence E of nitrogenase in the vesicles.Furthermore, our results suggested that nitrogenase localizesin the hyphae of the endophyte Frankia in Elaeagnus pungensnodules. 1Present address: Iwata Experiment Station, Japan Tobacco Inc.,Iwata-gun, Shizuoka 438, Japan. (Received March 9, 1988; Accepted July 28, 1988)  相似文献   
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