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971.
The prevalence of nonalcoholic fatty liver disease (NAFLD) has been rapidly increasing worldwide. A choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) has been used to create a mouse model of nonalcoholic steatohepatitis (NASH). There are some reports on the effects on mice of being fed a CDAHFD for long periods of 1 to 3 months. However, the effect of this diet over a short period is unknown. Therefore, we examined the effect of 1-week CDAHFD feeding on the mouse liver. Feeding a CDAHFD diet for only 1-week induced lipid droplet deposition in the liver with increasing activity of liver-derived enzymes in the plasma. On the other hand, it did not induce fibrosis or cirrhosis. Additionally, it was demonstrated that CDAHFD significantly impaired mitochondrial respiration with severe oxidative stress to the liver, which is associated with a decreasing mitochondrial DNA copy number and complex proteins. In the gene expression analysis of the liver, inflammatory and oxidative stress markers were significantly increased by CDAHFD. These results demonstrated that 1 week of feeding CDAHFD to mice induces steatohepatitis with mitochondrial dysfunction and severe oxidative stress, without fibrosis, which can partially mimic the early stage of NASH in humans.  相似文献   
972.
K Yokoo  S Ono 《Vacuum》1982,32(5):265-268
A new type of high-speed ion pump using a multipactor cathode is proposed and the experimental results, obtained with the first trial pump, are described. The multipactor cathode has excellent characteristics as an electron source in order to obtain increased pumping speed of an ion pump, namely: (1) since it is a cold cathode made of pure metal, such as Al, it does not contaminate the vacuum condition, (2) the electron emission density is high, (3) the supply of electrons can be greatly increased in comparison with that of any other supply method, (4) the electrons can be supplied easily into a very wide area.This proposal is to make a high-speed ion pump by combining such an attractive cathode with a normal ion pump. The experimental results showed that the maximum pump current per unit pump volume reached up to 30 times that of a normal ion pump in vacuum conditions of less than 10?4 Pa.  相似文献   
973.
974.
A membrane-bound hydrogenase was purified aerobically by one step using a hydroxyapatite column after solubilization by acetone treatment from a thermophilic hydrogen-oxidizing bacterium, Pseudomonas hydrogenothermophila strain TH-1. The enzyme consists of two polypeptides of 63 and 31 kDa, respectively. The amino-terminal amino acid sequences of both subunits were homologous to membrane-bound type [Ni-Fe] hydrogenases from other origins. The thermostability under a hydrogen gas atmosphere is highly stable at 50 degrees C, which is the optimum temperature for the cell growth.  相似文献   
975.
We experienced two cases of iatrogenic left main coronary artery stenosis (IOCS) following double (aortic and mitral) valve replacement (DVR). The solid coronary perfusion catheter may attribute IOCS, with grave consequence. There have been no IOCS since the time we exchanged a solid catheter for a soft one. One case, she was successfully treated percutaneous transluminal coronary angioplasty (PTCA), because she developed angina pectoris about 5 years after PTCA. But she developed angina pectoris again and angiographically left main coronary was severe stenotic. So she was undergone aorto coronary bypass grafting (CABG) to the left anterior descending. The other case, he developed angina pectoris about 3 months after DVR. He was treated with PTCA. Angiographically left mine coronary artery stenosis reduced 50% from 90%. Generally the treatment of IOCS is CABG, but we performed PTCA for 2 patients. Because we thought it was very hazardous for us to perform them open heart surgery. When it is very hazardous to perform patients open heart surgery, they need to be performed PTCA.  相似文献   
976.
Possible involvement that the pressor and positive chronotropic effects of endothelin-3 (ET-3) administered intracerebroventricularly (i.c.v.) participate in the central beta-adrenoceptor has been studied in urethane anesthetized rats. ET-3 administered i.c.v. at dose of 50 pmol elicited the increase in blood pressure and heart rate over a long duration, but a dose of 30 pmol had a minimal effect. These cardiovascular responses to ET-3 were significantly reduced by intravenous pretreatment with pentolinium, ganglionic blocking agent, and phentolamine, alpha-blocker. Also pressor responses to ET-3 were abolished dose-dependently by i.c.v. pretreatment with propranolol at a dose of 1 mumol, nonselective beta-blocker and ICI 118551, beta 2-selective adrenoceptor blocker, but not by i.c.v. pretreatment with metoprolol, atenolol, beta 1-selective blocker, procaine and phentolamine. These results suggest that ET-3 may play a role in cardiovascular regulation through the activation of the sympathetic nervous system involved in the central beta 2-adrenoceptor system.  相似文献   
977.
978.
979.
Optical duobinary signals have been applied to dense wavelength division multiplexing (WDM) systems with high-spectral efficiency to fully utilize a limited gain bandwidth of about 35 nm (4.4 THz) for an erbium-doped fiber amplifier (EDFA). These signals are one type of partial response signals and have narrower bandwidth than conventional intensity modulation (IM) signals. Thus, the use of these signals should make possible to attain ultradense WDM systems. In this paper, characteristics of optical duobinary and IM signals in ultradense WDM systems are compared through experimental evaluations at 20 Gb/s. High-spectral efficiency of 0.6 b/s/Hz was reached in this demonstration  相似文献   
980.
To determine which diagnoses in the emergency department (ED), apart from battering injuries, were more common among women who were living in physically abusive relationships than among women who were not, a study was conducted in 10 hospital-based EDs in two cities serving inner city, urban, and suburban populations. A total of 9,057 women between the ages of 19 and 65 years presenting to the EDs were eligible for the study. Medical records were reviewed, and a written questionnaire was used. The questionnaire was completed by 4,501 (73% of those asked, 59% of those eligible, and 50% of those presenting). Two hundred sixty-six (5.9%) were currently in a physically abusive relationship but not in the ED for battering injuries, and 3,969 (88.2%) were not currently in a physically abusive relationship. An additional 266 (5.9%) were positive, probable, or suggestive for battering injuries and excluded from diagnosis comparisons. Women in physically abusive relationships were more likely to be diagnosed with urinary tract infections, neck pain, vaginitis, foot wound, suicide attempt, and finger fracture. However, these represented only 19.8% of diagnoses in this group. The use of this knowledge alone to predict the presence of intimate violence in individual patients in the ED will not identify the majority of women at risk. These results suggest the use of routine inquiry for abuse in all women.  相似文献   
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