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101.
The list of LDL receptor superfamily relatives is still growing. The two most recently discovered family branches are (1) a set of receptors characterized by expression in brain and a very close relationship to the LDL and VLDL receptors, and (2) highly cross-species (man, mouse, rabbit, chicken) conserved complex mosaic receptors which contain structural domains so far not found in the superfamily. At present, we know very little about the physiological function(s) of these molecules. They can be safely assumed, based on the presence of seven, eight or 11 clustered LDL receptor ligand binding repeats, to recognize mammalian apolipoprotein E but, based on the absence of apolipoprotein E in birds, they may exhibit interactions quite different from and/or in addition to typical lipoprotein receptors in vivo.  相似文献   
102.
The objective of this investigation is to stabilize a sensorless vector control system of induction motors by means of an adaptive observer in regenerating mode at very low speed. The adaptive observer gain is designed by means of the Routh–Hurwitz criterion. It is verified by simulation and experiment that the proposed system is stable. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(4): 78–87, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10202  相似文献   
103.
One hundred and twelve forearms in 56 preserved cadavers were dissected to assess the incidence of Martin-Gruber connections in a population in South Africa. The connections were found in 13 cadavers (23%) and one was bilateral. There were no significant racial or sexual differences in the incidence. The course of Martin-Gruber connections and their anatomical relationship with the ulnar artery are illustrated.  相似文献   
104.
The mechanics of the condensing behavior of vapor bubbles in a subcooled bulk flow is complicated and influenced by both heat and mass transfer. To examine the characteristics of such thermal-nonequilibrium two-phase flow, experimental and analytical researches have been made. In the experiment, the movement of each vapor bubble in a flowing channel was recorded on video tapes and analyzed by an image processing system. As result, the distributions of void fraction along the test section were obtained. In the analysis, a simple analytical model was introduced to predict the distributions of void fraction and liquid subcooling temperature. By considering the rate of vapor condensation along the flow direction, the differential equation of energy balance between two phases was obtained. Integration of this equation yielded the void fraction and bulk liquid subcooling at any position. The condensation rate was estimated as a function of the local liquid subcooling, interfacial area and mass velocity. Finally, a close fit between calculated results and experimental data was obtained.  相似文献   
105.
Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) produced by various bacteria has been intensively investigated as a promising biodegradable plastic, but required a supply of an expensive precursor as a secondary carbon source for its production. In a previous study, we identified a new bacterial strain, Rhodococcus aetherivorans IAR1, which synthesizes PHBV from toluene without the supply of a precursor. Toluene is the volatile organic compound most abundantly emitted to the environment. In the present paper, we show that R. aetherivorans IAR1 produces triacylglycerols (TAGs) simultaneously with PHBV. Both PHBV and TAGs were synthesized before the nitrogen source is completely exhausted. The cellular content of PHBV reached 10% of cell dry weight (CDW) and its synthesis ceased even during intermittent supply of toluene. However, accumulation of TAGs continued during cultivation and their cellular content reached 24% of CDW at the end of cultivation. Cerulenin inhibited TAG production and increased PHBV cellular content up to 30% of CDW. The mole fraction of 3-hydroxyvalerate (3HV) in PHBV produced from toluene increased from 60% to 80% during its accumulation. Fatty acid compositions of TAGs produced from acetate and toluene were different. At the end of cultivation, the mole fraction of C17:0, one of odd-carbon number fatty acids, was 5% on toluene or 10% on acetate while the mole fraction of 3HV in PHBV from toluene was as high as that in PHBV from acetate, suggesting that a C5 intermediate of toluene degradation might directly become a precursor of 3HV whereas propionyl-CoA is required for the incorporation of C17:0 into TAGs.  相似文献   
106.
107.
E.s.r. spectra of peroxy radicals trapped in isotactic and atactic polypropylenes have been observed at various temperatures. The spectrum observed at 77 K was shown to be composed of one component by comparing it with that at 4 K. The spectra observed at higher temperatures comprised of two spectra arising from the rigid peroxy radicals and the mobile peroxy radicals. All of the observed spectra have been reconstructed by means of computer simulation and the changes in anisotropic g-values with temperature were estimated. The motion of the mobile fraction was shown to be rotation or rotatory vibration of the radicals around the chain axis both in the isotactic polypropylene and in the atactic polypropylene as well as in polyethylene and poly(tetrafluoroethylene) although the structures of the polymers are different, that is helical (polypropylene) or planar zigzag (polyethylene, poly(tetrafluoroethylene)).  相似文献   
108.
A buried-channel p-MOSFET with a large-tile-angle implanted punchthrough stopper (LATIPS) is described. In this device the n+ LATIPS region was successfully realized adjacent to the p+ source/drain, even without a sidewall spacer, by taking advantage of the n+ large-tilt-angle implant. In spite of the relatively deep p+ junction of 0.2-μm depth and the low n-well concentration of 1×1016 cm-3, the 0.5-μm LATIPS device (with corresponding channel length of 0.3 μm) achieved high punchthrough resistance, e.g. a low subthreshold swing of 95 mV/decade with a high transconductance of 135 mS/mm  相似文献   
109.
Although studies have shown that arterial baroreflex sensitivity (BRS) is decreased in patients with acute myocardial infarction, BRS changes in patients with stable coronary artery disease (CAD) have not been studied extensively. We assessed BRS by the phenylephrine method in 55 normotensive and nondiabetic patients with chronic effort angina, old myocardial infarction, or both. The control group consisted of 24 age-matched patients without coronary lesions. To identify factors that determine BRS in stable CAD, we performed multivariate analysis using age, sex, left ventricular ejection fraction, pulmonary artery wedge pressure, resting systolic blood pressure, resting heart rate, the number of stenotic coronary arteries, history of myocardial infarction, and the presence or absence of angina pectoris as variables. BRS was significantly lower in patients with CAD than in control subjects (5.9 +/- 2.9 vs 6.9 +/- 2.4 ms/mm Hg, p < 0.05). In patients with CAD, BRS was inversely correlated with age, the resting heart rate, and the number of stenotic coronary vessels (p < 0.001, p < 0.005, and p < 0.005, respectively), but was independent of other clinical parameters, including the history of myocardial infarction. In control subjects, BRS was significantly correlated only with age. These results indicate that BRS is decreased in patients with stable CAD, and this decrease is correlated with the extent and severity of coronary narrowing.  相似文献   
110.
1. The effects of fluvastatin, a new 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, on the vascular angiotensin converting enzyme (ACE) activity in hyperlipidaemic rabbits were compared with those of enalapril, an ACE inhibitor. 2. Rabbits were fed a 1.5% cholesterol containing diet or normal diet for 16 weeks and treated with either fluvastatin or enalapril in the diet at the respective doses of 2 and 10 mg kg-1 day-1. The total cholesterol, triglyceride and phospholipid levels in serum were significantly increased in rabbits fed the high cholesterol diet. Treatment with fluvastatin but not enalapril resulted in a decrease in serum lipids. 3. The vascular ACE activities assessed via the cleavage rate from synthetic substrate in the aortic arches and upper thoracic aortae were increased by 8 to 10 times when the rabbits were made hyperlipidaemic. Fluvastatin as well as enalapril significantly lowered the tissue ACE in the aortae. 4. The ACE activities in serum did not alter in hyperlipidaemic rabbits either in the presence or absence of fluvastatin. The serum ACE activity was lowered by enalapril. 5. The lipid peroxide in serum as well as the plaque area in the thoracic aorta was significantly increased in the cholesterol diet-fed rabbits. Treatment with fluvastatin or enalapril reduced both serum lipid peroxide and plaque formation. The relaxant responses to acetylcoholine (ACh) were significantly suppressed in the cholesterol-fed rabbits. Treatment with fluvastatin or enalapril significantly reversed the suppression of ACh-induced relaxation. 6. It seems that the reduction of vascular ACE is not coupled to lipids and ACE activity in serum, but rather to lipid peroxidation. Thus, the decrease in vascular ACE activity by fluvastatin as well as the lipid-lowering effect may reduce the risk of atherosclerosis progression in the vasculature.  相似文献   
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