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61.
In order to study the regulatory mechanism of motilin release, plasma motilin was measured in healthy dogs during the fasting state and after the ingestion of ordinary nutrient. Fasting plasma motilin levels were found to fluctuate intermittently, but ingestion of a meal completely abolished the intermittent motilin release and resulted in low motilin levels lasting for 6–8 h. To clarify the role of the duodenum in this motilin release, an operation was performed in five dogs by which we excluded from the alimentary tract the upper half of the small intestine not including the duodenum from a point 2 cm below the larger pancreatic duct. After this operation meal ingestion still caused a decrease in plasma motilin levels. However, after a modified version of the operation was performed in 5 other dogs by which the upper half of the small intestine together with the duodenum was transected at the pyloric ring, plasma motilin was not suppressed by meal ingestion. These results suggest that motilin secretion is regulated by nutrient ingestion and that the passage of nutrients through the duodenum plays a important role in its regulation.  相似文献   
62.
A simple, rapid and highly specific method by selected ion monitoring (SIM), using 9α,11α-[2H2]estrone, [2,4-2H2]estradiol-17β and 2,4-[2H2]estriol as internal standards, was developed for the determination of serum estrogens during pregnancy. Serum samples were submitted to a simple extraction procedure and were analysed after formation of the trifluoroacetic anhydride derivative. The inter-assay coefficients of variation for estrone, estradiol-17β and estriol were 3.73%, 3.42% and 3.49%, respectively. The results obtained by SIM were compared with analysis performed using radioimmunoassay.  相似文献   
63.
An inducible enzyme catalysing the hydrolysis of (+)-usnic acid to (+)-2-desacetylusnic acid and acetic acid has been purified 150-fold from the mycelium of Mortierella isabellina grown in the presence of (+)-usnic acid. Purification was achieved by treatment with protamine sulfate, (NH4)2SO4 fractionation, negative adsorption on alumina Cγ gel and hydroxylapatite followed by chromatography on DEAE-cellulose and Sephadex G-200. The elution pattern from a Sephadex G-200 column indicated a MW of ca 7.6 × 104 for the enzyme. The apparent Km value for (+)-usnic acid at the pH optimum (pH 7) was 4.0 × 10?5 M. The enzyme was specific for (+)-usnic acid and inactive towards (?)-usnic acid, (+)-isousnic acid or certain phloracetophenone derivatives. Its activity was enhanced in the presence of divalent metal ions such as Co2+, Ni2+, Mn2+, Mg2+ and Zn2+.  相似文献   
64.
Summary The effect of ion-supplemented medium on peroxidase excretion from horseradish (Armoracia rusticana) hairy roots was studied. Supplementation of mannitol instead of ions revealed that the excretion was stimulated not by osmotic pressure in the medium but by ionic properties. Extracellular peroxidase activity per dry cell was proportionally correlated with the ionic strength of the cations. CaCl2 or MgCl2 was found to be the most effective agent for excretion among other combinations. CaCl2 supplementation at the beginning of the culture caused higher peroxidase production in the medium without a significant loss of final cell mass compared with CaCl2 addition during the culture. Repeated batch culture with 50 mM CaCl2 supplementation allowed a continuous retention of cell viability over 149 days and produced a great amount of extracellular peroxidase, 12-fold higher than that achieved in a 40-day-old batch culture with 50 mM CaCl2 supplementation. Correspondence to: T. Kobayashi  相似文献   
65.
Summary A hydrocarbon-rich green microalga, Botryococcus braunii, was able to grow well in secondarily treated sewage (STS) from domestic waste-water in a batch system. The growth in STS from domestic waste-water was as good as in the common artificial medium of modified Chu 13 and its hydrocarbon contents were high enough at 53% and 40% compared with 58% in the case of the modified Chu 13 medium. B. braunii utilized nitrate from 7.67 or 4.48 mg/l to a level below detection of < 0.01 mg/l in STS. After this consumption of nitrate, nitrite was consumed, and ammonium was not. Phosphate, even at an extremely low concentration, was also consumed by B. braunii. These results show the possibility of using STS as a medium to grow B. braunii and for removal of nitrogen and phosphorus by algal consumption in STS.Correspondence to: S. Yokoyama  相似文献   
66.
Summary A human yolk sac tumor cell line, TG1, which was established from a testicular yolk sac tumor, was found to replicate continuously in a chemically defined medium supplemented with Na2SeO3 (ISRPMI). TG1 produced several plasma proteins and growth factors: albumin, alpha-fetoprotein (AFP), ferritin, carcinoembryonic antigen, beta-2-microglobulin, polyamine, neuron specific enolase, tissue polypeptide antigen, transferrin (Tf), epidermal growth factor, and platelet derived growth factor. By analysis of lectin (LcHA)-affinity electrophoresis, to examine the microheterogeneity of carbohydrate chains of synthetic glycoproteins, TG1 cells cultured with ISRPMI produced only LcHA reactive Tf and AFP based on core fucose attached to asparagine-linkedN-acetylglucosamine residues instead of LcHA-nonreactive Tf and AFP produced by TG1 cells cultured with fetal bovine serum (FBS)-containing medium.α1-6 Fucosyltransferase activity was significantly greater in the TG1 cells cultured with ISRPMI (39.9±1.5 pmol · h−1 · mg−1 protein) than cultured with FBS-containing media (18.2±1.2 pmol · h−1 · mg−1 protein). These results have indicated that the selective increase ofα1-6 fucosyltransferase occurred when the cells were cultured with the FBS-free synthetic media.  相似文献   
67.
On the basis of 44 hindlimbs of 14 male and 14 female crab-eating monkeys (Macaca fascicularis), the morphology of the adductor muscles of the thigh was described and some functional indices were calculated. The results obtained from this study agreed generally with those of otherMacaca species reported by various authors. For the classification and nomenclature of the adductors, the criteria proposed byUhlmann (1967, 1968) was well adapted to the crab-eating monkey. The adductors comprise the m. gracilis, m. pectineus, m. adductor longus, pars longa and pars brevis of m. adductor brevis, pars lata and pars minima of m. adductor magnus and m. obturatorius externus. In males, the adductors are generally inserted further down the femur, and the insertions of pars brevis of the m. adductor brevis and pars minima of the m. adductor magnus have longer attachments to the femur than in females. The arrangement of each adductor muscle and of each fasciculus of a thigh muscle may invoke a principle of organization.  相似文献   
68.
A supernumerary muscle bundle “M. tubero-femoralis Fick” of the biceps femoris was found in a female crab-eating monkey in both hindlimbs.  相似文献   
69.
As a model compound for the growing chain in the activated-NCA type of polymerization of α-amino acid N-carboxyanhydride (NCA), 3-[ω-acetylglycyl-poly(α-amino acid) acyl]-α-amino acid NCA (called the prepolymer) having various degrees of polymerization (DPs) was synthesized by the polymerization of Phe, Val, Glu(OEt), and Asp(OBzl) NCA in the presence of AcGly NCA by the tertiary amine. Activated (S)-Phe, Val, Glu(OEt), and Asp(OBzl) NCA were added to the terminal cyclic group of the corresponding (S)- or (R)- prepolymer, and the enantiomer selectivity in the reaction was investigated. With prepolymers having DPs ranging from 1 to 15, the addition reaction always took place preferentially between species having the same configuration, and the degree of the enantiomer selection increased with increasing DP of the prepolymer. With prepolymers having DP = 1 and 2, we found contributions from the chiral terminal unit and the chiral penultimate unit to the enantiomer selection, respectively. Prepolymer having DP = 5 was shown to take a β-type conformation, which led to higher enantiomer selection; and prepolymers having DP = 10 and 15 were shown to take an α-helix conformation, which led to much higher enantiomer selection than did the β-type conformation. In the present investigation the mechanisms of terminal-unit control, penultimate-unit control and conformational control of the enantiomer selection in the activated-NCA type of polymerization were clearly observed.  相似文献   
70.
Tremorgenic Mycotoxin from Penicillium paraherquei   总被引:1,自引:1,他引:0       下载免费PDF全文
A tremorgenic mycotoxin was isolated from Penicillium paraherquei Abe ex G. Smith and identified as verruculogen. It was produced at the rate of approximately 1 mg/g of the dried fungal mycelium cultured on peptone-enriched Czapek-Dox medium at 28°C.  相似文献   
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