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51.
C G Scanes R V Carsia T J Lauterio L Huybrechts J Rivier W Vale 《Life sciences》1984,34(12):1127-1134
Synthetic human pancreatic Growth Hormone-Releasing Factor (hpGRF) elevated the plasma concentration of growth hormone (GH) in young and adult domestic fowl. This in vivo effect of hpGRF appeared to be largely similar for both the 32 amino-acid (hpGRF 1-32) or 40 amino-acid (hpGRF 1-40) polypeptide, although the effect of hpGRF 1-32 was more prolonged than that of hpGRF 1-40 in adult domestic fowl. The increase in plasma GH concentrations following hpGRF administration (10 micrograms/kg) was somewhat greater in young than adult chickens (the increase in plasma concentration of GH being 230 ng/ml at 1 week old, 282 ng/ml at 6 week old, 241 ng/ml at 10 weeks and 150 ng/ml in adults). In the adult domestic fowl hpGRF stimulated a greater increase in the plasma concentration of GH than did thyrotropin-releasing hormone (TRH). However in the young chicks TRH was more active. The in vitro release of GH from dispersed chicken pituitary cells was elevated by hpGRF (1-32) and hpGRF (1-40). 相似文献
52.
The isolation of eucannabinolide and three new sesquiterpene lactones from Schkuhria anthemoidea is reported. The structures and stereochemistries of the new compounds were established by chemical and spectroscopic means. The structure of santhemoidin B was confirmed by X-ray crystallography. 相似文献
53.
Isolation of yeast with killer activity and its breeding with an industrial baking strain by protoplast fusion 总被引:5,自引:0,他引:5
Adela Bortol Clara Nudel Elda Fraile Ramon de Torres Ana Giulietti J. F. T. Spencer Dorothy Spencer 《Applied microbiology and biotechnology》1986,24(5):414-416
Summary Wild strains of Saccharomyces cerevisiae were isolated from dairy products, bakery goods, fresh fruit and vegetables, and tested for killer activity. Four isolates out of 238 strains possessed killer activity. The best of these was converted to the petite form and hybridized with an industrial strain of Saccharomyces cerevisiae by protoplast fusion. Thirty-eight out of 104 isolates had killer activity, and some of these had good dough-raising activity as well. 相似文献
54.
Dr. Olivier Kah Bernard Breton Joseph G. Dulka Jésus Nunez-Rodriguez Richard E. Peter Anne Corrigan Jean E. Rivier William W. Vale 《Cell and tissue research》1986,244(2):327-337
Summary The organization of Gn-RH systems in the brain of teleosts has been investigated previously by immunohistochemistry using antibodies against the mammalian decapeptide which differs from the teleostean factor. Here, we report the distribution of immunoreactive Gn-RH in the brain of goldfish using antibodies against synthetic teleost peptide.Immunoreactive structures are found along a column extending from the rostral olfactory bulbs to the pituitary stalk. Cell bodies are observed within the olfactory nerves and bulbs, along the ventromedial telencephalon, the ventrolateral preoptic area and the latero-basal hypothalamus. Large perikarya are detected in the dorsal midbrain tegmentum, immediately caudal to the posterior commissure. A prominent pathway was traced from the cells located in the olfactory nerves through the medial olfactory tract and along all the perikarya described above to the pituitary stalk. In the pituitary, projections are restricted to the proximal pars distalis. A second immunoreactive pathway ascends more dorsally in the telencephalon and arches to the periventricular regions of the diencephalon. Part of this pathway forms a periventricular network in the dorsal and posterior hypothalamus, whereas other projections continue caudally to the medulla oblongata and the spinal cord. Lesions of the ventral preoptic area demonstrate that most of the fibers detected in the pituitary originate from the preoptic region. 相似文献
55.
Ana Rosa Santa Cruza Luis A. Quesada Allue Alberto Baldi 《Molecular and cellular biochemistry》1983,56(1):55-66
Microsomal preparations from malignant human breast tumors catalyzed the transfer of mannose and glucose from GDP-[14C]-Man and UDP-[14C]-Glc into lipid-linked sugars and glycoprotein-like substances. As judged by several criteria the obtained lipid-linked monosaccharides behaved as dolichyl phosphate mannose and dolichyl phosphate glucose whereas lipid-linked oligosaccharides behaved as polyprenyl diphosphate derivatives. The optimum conditions for mannosyl- and glucosyl-transfer reactions and the effect of dolichyl phosphate, detergent and EDTA on incubation mixture were described. 相似文献
56.
Two nomograms are presented. The first enables the mean surface and body temperatures and the body heat content of a patient of given weight to be determined from measurements of skin temperature at three sites and of the core (rectal) temperature. The second enables the change in heat content of such a patient to be determined from the change in mean body temperature. 相似文献
57.
A comparative study was done on some of the chemical changes occurring during autolysis of cultures ofAspergillus flavus in both physiologically acid and alkaline media. The mycelium ofA. flavus lost during autolysis 44 % of its maximum dry weight in the physiologically alkaline medium, whereas this loss was apparently nil in the physiologically acid medium. Nitrogen containing compounds seemed not to be affected by autolysis either in the physiologically acid or alkaline media. The disappearance of P-containing compounds in mycelium ofA. flavus autolysed in both conditions (NO
3
–
and NH
4
+
as N source) amounted to 64 % in the alkaline autolysis and to nearly 77 % in the acid autolysis. The results we have obtained for the acid autolysis strongly suggest that very little activity is shown by autolytic enzymes in the interval 10–133 days of incubation, when measuring autolysis by the loss in mycelial dry weight.
Zusammenfassung Eine vergleichende Untersuchung war unternommen an einigen der chemischen Veränderungen, die während der Autolyse der Kulturen vonAspergillus flavus in physiologischen sauren und alkalischen Medien vorkommen. Die Myzelien vonA. flavus haben während der Autolyse 44 % ihres größten Trockengewichtes in physiologisch alkalischem Medium verloren, während dieser Verlust in physiologisch saurem Medium anscheinend Null gewesen ist. Stickstoff enthaltende Substanzen erschienen während der Autolyse weder in physiologisch saueren noch in alkalischen Medien beeinflußt zu sein. Das Verschwinden von P-enthaltenden Substanzen in Myzelien vonA. flavus in Autolyse unter beiden Bedingungen (NO 3 – und NH 4 + als Stickstoffquelle) erreichte 64 % in alkalischer Autolyse und beinahe 77 % in der saueren Autolyse. Die Ergebnisse, die wir in der saueren Autolyse erhalten haben legen es sehr nahe, daß autolytische Enzyme eine sehr geringe Aktivität in der Zeitspanne von 10–133 Tagen der Inkubazion zeigen, wenn die Autolyse an dem Verlust des mycelialen Trockengewichtes gemessen wird.相似文献
58.
Summary In a study of the yeasts associated with insect frass underneath the bark ofTsuga heterophylla (the Pacific Coast hemlock) four new species of yeast were found. These were described asSporobolomyces singularis, Bullera tsugae, Cryptococcus skinneri andCandida oregonensis. Sporobolomyces singularis is a non-pigmented species, which required an amendment of the genus definition. Ballistospore formation of the new species
ofSporobolomyces and ofBullera was absent on malt agar and on potato glucose agar, but positive on corn meal agar. An unusual case of quantitative transgalactosylation
by growing cells ofSporobolomyces singularis on lactose has been described. It has been proposed to establish a “Candida parapsilosis Group” of species to whichC. oregonensis was assigned.
Supported by a fellowship of the Calouste Gulbenkian Foundation, Lisbon, Portugal. 相似文献
59.
60.
Summary Brush border membrane vesicles (BBMV) were prepared from the gills of the marine mussel,Mytilus edulis. These membranes contained two distinct pathways for cotransport of Na+ and -neutral amino acids. The major pathway in mussel gill BBMV was the alanine-lysine (AK) pathway, which had a high affinity for alanine and for the cationic amino acid, lysine. The AK pathway was inhibited by nonpolar -neutral amino acids and cationic amino acids, but was not affected by -neutral amino acids or imino acids. The kinetics of lysine transport were consistent with a single saturable process, with aJ
max of 550 pmol/mg-min and aK
t
of 5 m. The AK pathway did not have a strict requirement for Na+, and concentrative transport of lysine was seen in the presence of inwardly directed gradients of Li+ and K+, as well as Na+. Harmaline inhibited the transport of lysine in solutions containing either Na+ or K+. The alanine-proline (AP) pathway transported both alanine and proline in mussel gill BBMV. The AP pathway was strongly inhibited by nonpolar -neutral amino acids, proline, and -(methylamino)isobutyric acid (Me-AIB). The kinetics of proline transport were described by a single saturable process, with aJ
max of 180 pmol/mg-min andK
t
of 4 m. In contrast to the AK pathway, the AP pathway appeared to have a strict requirement for Na+. Na+-activation experiments with lysine and proline revealed sigmoid kinetics, indicating that multiple Na+ ions are involved in the transport of these substrates. The transport of both lysine and proline was affected by membrane potential in a manner consistent with electrogenic transport. 相似文献