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951.
Using a conventional sexual crossing technique, Nicotiana tabacum x N. acuminata was not produced. After the fertilized ovules were cultured for 20 days in a liquid Nitsch H medium, germination was observed. The roots grew rapidly but leaves did not. However, plantlets were produced in an H medium containing Benzyladenine or Kinetin (0.01–0.1 mg/l). The plantlets grew and flowered in a greenhouse. The chromosome number of the hybrid was 36 and its morphological characteristics were intermediate between those of parental species.Abbreviations BA Benzyl adenine - K Kinetin  相似文献   
952.
953.
The O-glycosidically-linked carbohydrate units of glycophorin from bovine erythrocyte membrane were released by alkaline borohydride treatment. These oligosaccharides were separated into the neutral fractions and the acidic fractions by ion-exchange chromatography followed by gel filtration. The two acidic fractions (fractions 10 and 13) which have the smallest molecular weight in acidic oligosaccharides, were further purified by gel filtration on Bio-Gel P-4 column. Two acidic oligosaccharides (fractions 10-I and 10-II), heptasaccharides, were separated by gel filtration on a Bio-Gel P-4 column from fraction 10. These structures were determined by methylation analyses, nitrous acid deamination after hydrazinolysis and Smith degradation after desialylation. In addition, the structures were also analyzed by direct-probe mass spectrometry of the permethylated derivatives before and after desialylation. These studies indicated that one of them (fraction 10-I) was NeuNGcα(2→3)Galβ(1→4)GlcNAcβ(1→3)Galβ(1→4)GlcNAcβ(1→3)Galβ(1→3) GalNAcol and another heptasaccharide (fraction 10-II) was Galβ(1→4)GlcNAcβ(1→3)Galβ(1→3) [NeuNGcα(2→3)Galβ(1→4)GlcNAcβ(1→6)]GalNAcol. Athough another acidic fraction (fraction 13) was obtained as a single peak on a Bio-Gel P-4 column, it appeared to be the mixture of a heptasaccharide, NeuNGcα(2→3)Galβ(1→4)GlcNAcβ(1→3 or 6)[Galβ(1→4)GlcNAcβ(1→6 or 3)]Galβ(1→3)GalNAcol and an oligosaccharide similar to fraction 10-II, by analysis of two products obtained by Smith degradation after desialylation.  相似文献   
954.
The existence of specific progesterone-binding sites with a high affinity and a limited capacity was demonstrated by [3H]progesterone exchange in the nuclear fractions of the pituitary and hypothalamus as well as in those of the oviduct magnum in the hen.  相似文献   
955.
An epidemic of pharyngoconjunctival fever due to adenovirus type 3 occurred among children in a primary school in Japan during summer months of 1964. The etiologic diagnosis of the epidemic was readily made by virus isolation and serologic tests on patients. Adenovirus type 3 was isolated in HeLa cell cultures from 55% of 52 patients, and serologic evidence for type 3 virus infection was obtained in 93% of 54 patients which were tested for complement-fixing, neutralizing, and hemagglutination-inhibiting antibodies. The HI test was found to be as useful in the serologic diagnosis of the serotype as the NT test. It is evident that for the routine use, the HI test is more advantageous than NT test as the latter is more laborious and time consuming. The fact that a strain recovered in this epidemic gave higher HI titers than the prototype strain, when used as the antigen in HI tests with sera of patients in this epidemic indicates the desirability of selecting an appropriate virus strain for preparation of the antigen for HI test in serological diagnosis of patients.  相似文献   
956.
Porcine ovary was found to contain enzyme activities hydrolyzing peptide 4-methylcoumaryl-7-amide (MCA) substrates with a preference for Arg-MCA bond. The activities were shown to be present almost exclusively in the follicular fluid and to increase several times during follicular maturation. The enzyme responsible for these activities is thought to be a serine proteinase as judged from its strong inhibition by diisopropylfluorophosphate (DFP), leupeptin and antipain. The molecular weight of the native enzyme was electrophoretically estimated to be approximately 350,000, the result indicating that the enzyme is clearly distinct from plasmin (M(r) = 80,000) and collagenase (M(r) = 30,000-65,000), both of which are thought to be involved in ovulatory process. The substrate specificity of the partially purified enzyme was qualitatively different from that of plasmin. These results suggest that the enzyme is a novel type of serine proteinase.  相似文献   
957.
958.
Two distinct cell groups contain α-melanocyte-stimulating hormone-like immunoreactivity in rat hypothalamus. Only one group, located in the arcuate nucleus, contains other opiocortin peptide immunoreactivity. Combined immunocytochemistry, radioimmunoassay and high performance liquid chromatography, using two different antisera, were used in an attempt to characterise the immunoreactive material present in each cell group. The results thus obtained from normal rats, using an antiserum against α-melanocyte-stimulating hormone and one against COOH-terminal adrenocorticotropin, were compared with those obtained from rats treated neonatally with monosodium glutamate, which destroys the arcuate nucleus.In animals treated with monosodium glutamate, cells of the arcuate nucleus, staining with both antisera, were reduced in number. Cells containing only α-melanocyte-stimulating hormone-like immunoreactivity in the lateral hypothalamus were unaffected. Peptide levels detected by radioimmunoassay with both antisera were reduced in parallel. Chromatographed extracts showed parallel reductions in α-melanocyte-stimulating hormone-like and COOH-terminal adrenocorticotropin-like immunoreactivities.These results suggest that if the immunostained cells of the lateral hypothalamus contain conventional α-melanocyte-stimulating hormone, it constitutes only a very small proportion of the total hypothalamic concentration. However, the possibilities that the antiserum is crossreacting with a different molecular species, or with a similar compound synthesised by a different pathway cannot be excluded.  相似文献   
959.
960.
Large and small subunits of fraction I proteins from five plants (tobacco, paprika, tomato, eggplant and potato) of the family Solanaceae were isolated, and the triptic peptides of these subunits were compared after separation by ion exchange column chromatography. Using tobacco as the standard for comparison, 4 (paprika), 5 (tomato), 3 (eggplant) and 8 (potato) out of 27 resolved large subunit peptides were found to be different. On the other hand, 2 (paprika), 3 (tomato), 2 (eggplant) and 7 (potato) out of 15 clearly resolved peptides were found to be different from tobacco in the case of small subunit. These differences were appreciably bigger than those found for different species of the genus Nicotiana to which tobacco belongs. The tryptic peptides of more distantly related plants from tobacco (comfrey, spinach and rape) differed more than those of Solanaceae in either large or small subunit.  相似文献   
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