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261.
262.
Atrophy of the lymphoid tissues of mice induced by extracts of the submaxillary gland 总被引:2,自引:0,他引:2
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W. Arnoldo Levy Ivan Herzog Kunihiko Suzuki Robert Katzman Labe Scheinberg 《The Journal of cell biology》1965,27(1):119-132
No significant change was found in the electrolytes and lipids of the brain analyzed after glutaraldehyde fixation by perfusion of laboratory animals; such fixation also satisfactorily preserves neural tissues for electron microscopy. The brains of normal and tumor-bearing C3H mice, Wistar rats, and New Zealand rabbits were studied. Little difference was found in the dry weight and the content of sodium, potassium, total lipid and lipid fractions, and in the sulfate space (S35O4) between specimens from unperfused and perfused animals, whether normal or tumor-bearing. The results suggest the possibility of using selected regions of the nervous system, dissected after fixation, for chemical study and at the same time characterizing similar regions morphologically with the electron microscope. 相似文献
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267.
Masahiro Miyazaki Yasunori Suzuki Munehiro Oda Akira Kawai Liyan Bai Jiro Sato 《In vitro cellular & developmental biology. Plant》1989,25(9):839-848
Summary For serum-free primary culture of adult rat hepatocytes, a synthetic medium DM-160 and rat-tail collagen were selected for
the basal medium and for the culture substratum, respectively. Barbiturates, such as phenobarbital and 1-ethyl-5-isobutylbarbiturate,
efficiently supported survival of hepatocytes and maintained their morphologic features at lower concentrations under the
serum-free conditions than under the serum-supplemented conditions. However, the hepatocyte survival rates under the serum-free
conditions were lower than those under the serum-supplemented conditions in the presence or absence of barbiturates. Supplementation
of the basal medium with a combination of five groups of factors (5Fs), such as eight amino acids (Ala, Arg, Gly, Ile, Met,
Phe, Pro, and Trp), two unsaturated fatty acids (linoleate and oleate), a protease inhibitor (aprotinin), three vitamins (A,
C, and E), and five trace elements (Mn, Fe, Cu, Zn, and Se), improved the hepatocyte survival under the serum-free conditions
in the presence or absence of barbiturates. In other words, the serum could be completely substituted by the 5Fs. Hepatocyte
cultures maintained in the 5Fs-suppelemented basal medium showed excellent induction of tyrosine aminotransferase activity
in response to dexamethasone in the presence or absence of barbiturates. The efficiency of the 5Fs-supplemented basal medium
for maintaining hepatocytes was not inferior to those of other media in common use with hepatocytes, such as Williams' medium
E and Waymouth's medium MB-752/1. In conclusion, maintenance of functional hepatocytes in serum-free primary culture could
be improved by use of the new medium preparation (the 5Fs-supplemented DM-160) in the presence of barbiturates.
This work was supported by a grant no. 61771923 from the Ministry of Education, Science and Culture of Japan. 相似文献
268.
Nobuhiro Suzuki Kazuhiro Umezawa Toru Yabe Hisayuki Murai 《Ichthyological Research》1989,36(3):318-326
The development of the eggs and larvae and minute tubercles on the skin surface ofParacheilognathus himantegus larvae were observed. The egg began to hatch approximately 68 hours after insemination and the larvae reached the free-swimming stage 23 days after hatching at water temperature of 22±1°C. The larval development and minute tubercles on the skin surface of this species were similar to those ofAcheilognathus lanceolata, A. limbata, A. signifer andTanakia tanago. However, the shape of the ripe eggs ofP. himantegus differed from those of the four species. As regards the shape of eggs, there was a common characteristic amongP. himantegus, Rhodeus uyekii andA. limbata from Korea. As regards larval development,P. himantegus had two characters also found inRhodeus. These facts seem to suggest thatP. himantegus is closely related toA. lanceolata, A. limbata, A. signifer andT. tanago but is more specialized than these four species, except forA. limbata from Korea. 相似文献
269.
Erythrocyte-supplying function of the spleen was examined in the rainbow troutSalmo gairdneri under exercise. The spleen showed remarkable reduction, about 70% in weight and about 85% in hemoglobin content, after forced exercise of 15 min. The amount of erythrocytes released from the spleen was 2.33 ml/kg body, and this amount corresponds to about 20% of the total volume of circulating erythrocytes in resting condition. No damage was observed at the spleen, splenic artery and splenic vein after the exercise. Examination of the vascular system by a corrosion casting method showed that no place other than the venous circulation exists for the erythrocytes released from the contracted spleen. The spleen was strongly constricted by infusion of adrenaline into the organ. These facts imply that the fish spleen supplies stored hemoglobin into the circulating blood in response to an increased demand of oxygen during exercise, under the control of the sympathetic nervous system. 相似文献
270.