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1.
The liver lipogenic enzymes are compared among rats, chickens, frogs and fish. Although the apparent Km values of glucose-6-phosphate
dehydrogenase for glucose-6-phosphate are not much different among all the species, those of malic enzyme for malate are much
higher in chickens and fish than in rats and frogs. Glucose-6-phosphate dehydrogenase showed very high activities compared
with malic enzyme in fish liver, and malic enzyme showed high activities in chicken liver. Although the apparent Km values
of acetyl-CoA carboxylase and fatty acid synthetase for substrates are in the same range among all the animals, the activity
of acetyl-CoA carboxylase seems to be extremely low in fish and frog livers, and that of fatty acid synthetase is low in frog
livers only. In addition, the apparent Km values of α-glycerophosphate acyltransferase of fish liver are very high, and the
enzyme activity appears to be extremely low compared to the others. Therefore, the enzymes at the first steps of both fatty
acid and glycerolipid syntheses of poikilothermos animals appear to be very low. On the other hand, the Ouchterlony double-diffusion
patterns showed that the lipogenic enzymes of chickens, frogs and fish are immunologically different from those of rats, with
the exception of acetyl-CoA carboxylase in chickens. Therefore, it is suggested that the fatty acid and glycerolipid forming
systems of poikilothermos animals are quite different from those of homoiothermos and the lipogenesis is very low in poikilothermos. 相似文献
2.
This paper is concerned with the stability analysis of a networked control system, wherein communication from the controller to the plant input is through a digital channel subject to packet-dropouts and finite-level quantization. No acknowledgments of receipt are available to the controller. To alleviate the effect of packet-dropouts, the controller transmits tentative plant input sequences. Within this setup, we derive a sufficient condition for small ?∞ signal ?∞ stability of the networked control system. This condition requires the maximum number of consecutive packet-dropouts to be bounded. We also elucidate the trade-off which exists between the disturbance attenuation and the step size of the quantizer and the maximum number of consecutive packet-dropouts. 相似文献
3.
Motonaka Kuroda Yumiko Kato Junko Yamazaki Naoko Kageyama Toshimi Mizukoshi Hiroshi Miyano Yuzuru Eto 《Food chemistry》2012
The determination of the kokumi peptide, γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly) in raw scallop and processed scallop products was carried out using high pressure liquid chromatography–tandem mass spectrometry (LC/MS/MS). The detection of γ-Glu-Val-Gly was achieved using a multiple reaction monitoring (MRM) method. The optimised condition enabled the precise determination of γ-Glu-Val-Gly. Raw scallop contained 0.08 μg/g γ-Glu-Val-Gly, and the γ-Glu-Val-Gly levels in processed scallop products, such as dried-scallop and scallop extract, were measured to be 0.64 and 0.77 μg/g, respectively. This is the first report to confirm the existence of γ-Glu-Val-Gly in foodstuff. 相似文献
4.
Carbon coating of anatase-type TiO2 through their precipitation in PVA aqueous solution 总被引:1,自引:0,他引:1
Fine particles of photocatalytic anatase-type TiO2 prepared through hydrolysis of titanium-tetraisopropoxide were coated by carbon through their precipitation in poly(vinyl alcohol) (PVA) aqueous solution, followed by heat treatment at high temperatures of 400-1000 °C in a flow of high purity Ar. Without carbon coating, the phase transformation from anatase to rutile started above 600 °C, but it was suppressed up to 800 °C with carbon coating. Suppression of the phase transformation depended on the amount of carbon coated, apparent suppression being observed with carbon content above 5 mass%. The amount of carbon coated on anatase was controlled by changing the concentration of PVA in the solution. In order to have a carbon content of about 5 mass%, a PVA solution with more than 2 mass% had to be used. 相似文献
5.
M.B. Gaifullin Yuji Matsuda N. Chikumoto J. Shimoyama K. Kishio R. Yoshizaki 《Journal of Low Temperature Physics》1999,117(5-6):1229-1233
Josephson plasma resonance for underdoped Bi
2
Sr
2
CaCu
2
O
8+
and Bi
2
Sr
2
CuO
6+
have been measured by sweeping the microwave, frequency continuously. The resonance enables us to determine the superfluid density and quasiparticle conductivity in the c-axis accurately. We show that the. superfluid response and the low energy excitations out of the condensate in the c-axis of these materials are very different from those in the ordinary Josephson multilayer tunnel junctions. The Josephson coupling energy in single layer Bi
2
Sr
2
CuO
6+
is more than 5000 times smaller than is predicted in interlayer tunneling model. 相似文献
6.
Shuichi Kawamata Kiichi Okuda Takahiko Sasaki Ryozo Yoshizaki 《Journal of Low Temperature Physics》1999,117(3-4):891-895
The magnetic field direction dependence of the magnetic torque in the superconducting state of Bi
2
Sr
1.65
La
0.35
CuO
6+
(Bi2201) single crystal has been measured in several static magnetic fields up to 200 kOe. The applied field dependence of the anisotropy parameter, , defined by the square root of the effective mass ratio has been obtained by fitting the magnetic torque curves at 17 K by means of the effective mass model. For Bi
2
Sr
2
CaCu
2
O
8+
(Bi2212), the values up to 210 kOe were reported previously. At each field, for Bi2201 is larger than that for Bi2212. Since the value decreases as the field increases both for Bi2201 and Bi2212, the reduction of by the application of the high magnetic field is considered to be common for Bi-based layered superconductors. 相似文献
7.
8.
The author argues that the present status and future direction of liberalization of the telecommunications business in the wake of the breakup of AT&T must be considered from two viewpoints. One viewpoint approaches the telecommunications business as a public business; the other approaches it as a means to promote, in various countries, advancement and diversification of universal telecommunications. In this context he evaluates the impact of the breakup on communication policy worldwide 相似文献
9.
10.
Mok-Ryeon Ahn Shigenori Kumazawa Yumiko Usui Jun Nakamura Mitsuo Matsuka Fang Zhu Tsutomu Nakayama 《Food chemistry》2007,101(4):1383-1392
Propolis is a resinous substance collected by honeybees from various plant sources. The composition of propolis depends on time, vegetation, and the area of collection. This study examined the antioxidant activity of propolis from various areas of China: Heilongjiang, Neimongol, Hebei, Shandong, Shanxi, Gansu, Henan, Hubei, Sichuan, Hunan, Yunnan and Hainan. Ethanol extracts of propolis (EEP) were prepared and evaluated for their antioxidant activities by β-carotene bleaching, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging, and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation decolorization assays. Furthermore, the major constituents in EEP were identified by high-performance liquid chromatography (HPLC) analysis with a photodiode array (PDA) and mass spectrometric (MS) detection, and each component was quantitatively analyzed. All propolis samples except that from Yunnan had relatively strong antioxidant activity accompanied by high total polyphenol contents. Propolis with strong antioxidant activity contained large amounts of antioxidative compounds, such as caffeic acid, ferulic acid and caffeic acid phenethyl ester. On the other hand, propolis from Yunnan and Hainan had compounds not present in propolis from other areas. 相似文献