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101.
Summary The cuticle from adultGaigeria pachyscelis was isolated by solubilizing the internal tissues with sodium dodecyl sulphate (SDS) at 37°C. Cuticular protein was extracted with guanidine-HCl and -mercaptoethanol and purified by ammonium sulphate fractionation and DEAE-cellulose chromatography. SDS-polyacrylamide gel electrophoresis of purified protein revealed 2 polypeptides with apparent mol. wts of 58,000 and 74,000. As judged from their hydroxyproline content both of them are collagenous in nature. Results of gel filtration indicate that cuticular collagen exists in two forms, a non-associated form at low concentration and an associated form at high concentration.Acknowledgments. We thank Drs L.N. Singh and H.C. Tewari for providing the necessary facilities. Laboratory assistance of Mr Ram Kishore is highly appreciated. 相似文献
102.
Summary The level of the acid hydrolases -glucuronidase (EC 3.2.3.11), acid phosphatase (EC 3.1.3.2) and acid protease (EC 3.4.4) was studied during larval growth and molting inP. ricini. The level of activity of these enzymes remained low during larval growth; however, the level increased sharply at the time of molting and declined sharply thereafter in the newly ecdysed insect. Interestingly, the diminished activity of these enzymes was almost quantitatively recovered in the cast-off cuticle. The excretion of acid hydrolases through the cast-off cuticle has hitherto not been reported in insects during molting. 相似文献
103.
M. Tardy B. Rolland J. Bardakdjian P. Gonnard 《Cellular and molecular life sciences : CMLS》1978,34(9):1137-1138
Summary -(4-chlorophenyl)-GABA, a GABA mimetic compound, acts as an inhibitor of GABA metabolism in both synaptosomal and extrasynaptosomal compartments. It has no significant action on GABA or Glu uptake by synaptosomes. 相似文献
104.
N. Michajlovskij V. Štrbák O. Földes 《Cellular and molecular life sciences : CMLS》1978,34(3):409-410
Summary The administration of thiocyanate to rats caused a significant increase of serum free thyroxine fraction, which coincided with the significant decrease of TSH level. The other components (AFT4, T4, T3) in serum at this time were decreased or unchanged. The finding suggests the role of free thyroxine fraction in feed-back regulation of TSH secretion.Acknowledgment. We thank Dr A. Parlow and the NIAMDD, Rat Pituitary Hormone Distribution Program, for material for rat TSH immunoassay; Dr J. Nauman (Inst. Postgrad. Med., Warsaw, Poland) for T3 antibody, and to Ing. J. Sadlo, Mrs M. t'astná and Miss R Fajkoová for technical assistance. 相似文献
105.
Summary Pentobarbital concentrations of 10–100 M selectively inhibited the noradrenaline release evoked by activation of the nicotinic receptors on the terminals sympathetic nerves of the rabbit heart. Higher concentrations also decreased the noradrenaline release induced by KCl or by electrical stimulation of the nerve axons.This paper is dedicated to Professor Dr. G. Malorny on the occasion of his 65th birthday.Acknowledgment: We thank Mrs G. Thielecke for technical assistance. 相似文献
106.
B. Stankiewicz-Choroszucha J. Górski 《Cellular and molecular life sciences : CMLS》1978,34(3):357-358
Summary It was shown in the rat that mobilization of intramuscular triglyceride during exercise is controlled by the adrenergic system.Acknowledgments. The work was supported by the Polish Academy of Sciences, grant No. 10.4.2.01.3.2. 相似文献
107.
B. Jazdowska-Zagrodzińska B. Matuszewski 《Cellular and molecular life sciences : CMLS》1978,34(6):777-778
Summary Lamellar structures in oogonial and spermatogonial cells of gall midges were found to form a complicated system of intranuclear compartments inside which all heteropycnotic chromosomes present in the germ-line cells of these insects are located. In this way, the heteropycnotic S-chromosomes are separated by the nuclear lamellae from the remaining, decondensed chromosomes (E-chromosomes) of the interphase germ-line nucleus.This investigation was supported in part under Contract DPKBN/52/76-II.1.3.10. with the Polish Academy of Sciences. 相似文献
108.
M Debray-Sachs M Dy H Aurengo B Descamps 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(2):249-252
CBA Mice were immunized by two intraperitoneal injections of 30 X 10(6) DBA/2 or C57BL/6 spleen cells at days--12 and--2. Peritoneal cell population was obtained at day zero by washing the peritoneal cavity of Mice. Adherent cells were then separated using a 2 hrs. incubation in "Falcon" plates followed by washing. This macrophage-rich peritoneal cell population was found nonspecifically cytotoxic against 51Cr labeled tumoral target cells: P815 X DBA/2 mastocytoma cells, EL4 X C57BL/L lymphoma cells and spontaneous lymphoma AKR cells (same H--2k as CBA). This adherent peritoneal cell cytoxicity was demonstrated after 24 hrs. incubation with the target cells. It was found in nonspecific combination as well as when using target cells syngeneic to the donor. These findings suggest that adherent peritoneal cell cytotoxicity could be at least partly due to macrophages and result from factor (s) released by sensitized lymphocytes in vivo in the same way as has been previously demonstrated in vitro. 相似文献
109.
Triiodothyronine injected daily to pregnant rats for the last week of gestation (50 microgram/100 g b.wt) increased the specific activities of 5 acid glycosidases in the fetal forebrain and cerebellum. Cortisone (50 mg/100 g b.wt) administered in the same period had no effect on cerebellum acid hydrolases, but decreased their activity in the forebrain. 相似文献
110.
J Montreuil B Fournet G Spik G Strecker 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,287(8):837-840
The construction of molecular models for the human serotransferrin glycans shows that they present one compact section linked to the protein and constituted by the pentasaccharide alpha-Man-(1 leads to 3)-[alpha-Man-(1 leads to 6)]-beta-Man-(1 leads to 4)-beta-GlcNAc-(1 leads to 4)-beta-GlcNAc-(1 leads to)-Asn to which are attached two "antennae" consisting of the trisaccharide alpha-NANA-(2 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc. The trisaccharide sequence beta-Man-(1 leads to 4)-beta-GlcNAc-(1 leads to 4)-beta-GlcNAc adopts a flat and rigid conformation, stabilised by hydrogen bonds. In contrast, the sequence alpha-NANA-(1 leads to 6)-beta-Gal-(1 leads to 4)-beta-GlcNAc-(1 leads to 2)-alpha-Man takes up a helical configuration. The two "antennae" can be disposed on the pentasaccharide core to give two possible configurations, one Y-shaped and the other T-shaped. In both cases, the general conformation of the glycans is perfectly compatible with their postulated role as a recognition signal. 相似文献