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1.
Lack of effect of aspartame or of L-phenylalanine on photically induced myoclonus in the baboon, Papio papio 总被引:1,自引:0,他引:1
The effects of large doses of L-phenylalanine and of aspartame on seizure susceptibility and severity have been assessed in baboons Papio papio from Senegal which show photosensitive epileptic responses similar to primary generalised epilepsy in man. L-Phenylalanine, 50, 150 or 450 mg/kg, or aspartame, 300 or 1000 mg/kg, were administered orally. Peak plasma L-phenylalanine concentrations of approximately 2000 mumoles/l occurred 1-4 h after the highest dose of L-phenylalanine or aspartame. The plasma L-phenylalanine to large neutral amino acid ratio increased approximately 30-fold at this time. Compared with water administration there were no changes in epileptic responses 1-5 h after either treatment. In this primate model of epilepsy acute increases in plasma phenylalanine concentration are neither pro- nor anticonvulsant. 相似文献
2.
We used the intragastric feeding rat model for alcoholic liver disease to investigate alterations in glucose transporter isoforms GLUT 1 and GLUT 2 in response to different dietary fats and ethanol. Six groups of rats (three rats/group) were fed ethanol or dextrose with either saturated fat, corn oil, or fish (menhaden) oil. All control animals were pair fed the same diets as ethanol-fed rats except that ethanol was isocalorically replaced by dextrose. In all animals, the following were assessed: pathological changes in the liver, immunohistochemical and Western blot analysis of GLUT 1 and GLUT 2 isoforms, and glycogen distribution. The most severe pathological changes were seen in fish oil/ethanol fed rats, moderate changes were seen in the corn oil/ethanol group and no changes were observed in the dextrose-fed or saturated fat/ethanol groups. In the groups of rats showing pathological liver injury (corn oil/ethanol and fish oil/ethanol), the depletion in liver glycogen was accompanied by decreased GLUT 2 expression and increased GLUT 1 expression. A decrease in glycogen and GLUT 2 expression was also seen in the fish oil/dextrose-fed rats. We hypothesize that the shift in glucose transporters from GLUT 2 to GLUT 1 probably reflects a compensatory response to attenuated gluconeogenic activity and to meet the increased intracellular demand for glucose. This demand for glucose in the presence of depleted glycogen may serve to provide a source for ATP synthesis in the centrilobular zone where hypoxia occurs secondary to ethanol metabolism. 相似文献
3.
A rare case of congenital lumbar hernia associated with carpus equina varus is described in a week old baby. The treatment is described with limited review of the literature. 相似文献
4.
In a study of apparently healthy males, we noted a correlation between serum albumin and high density lipoprotein cholesterol (HDL-C) (r = 0.32, p less than 0.001). We then correlated the total cholesterol:albumin ratio (TC:Alb) with the TC:HDL-C ratio (r = 0.89, p less than 0.001). We used the TC:Alb ratio to determine whether this was better than TC by itself in predicting whether an individual had a TC:HDL-C ratio of less than or greater than or equal to 5. The ratio performed better than TC and correctly classified 89% of individuals (66% with TC) (p less than 0.001). Since measurements of TC and Alb are routinely available on multichannel analysers, use of this ratio would provide a less expensive alternative to HDL-C measurement. 相似文献
5.
Comparison of hospital staff performance when using desk top analysers for "near patient" testing. 总被引:1,自引:1,他引:1 下载免费PDF全文
The quality and reliability of four desk top analysers were evaluated. In the context of an outpatient clinic, intensive care unit, and a mock up of a physician's office. Seventeen nurses, 14 physicians, and 12 medical office personnel took part in the study. The instruments and tests evaluated were Reflotron (glucose, cholesterol, triglycerides, gamma-glutamyl transferase), Seralyzer (creatinine, glucose, potassium, aspartate aminotransferase), Vision (glucose, (creatinine, glucose, potassium, aspartate aminotransferase), Vision (glucose, urea, cholesterol, triglycerides alkaline phosphatase, uric acid), and DT60 (sodium, potassium, glucose, amylase, uric acid and creatinine). Of the 320 tests performed on the Vision, only two differed by more than 10% between the specialist staff and other groups. For those performed on the Seralyzer, 95 of 254 results differed by more than 10%, 19 of 199 by more than 10% for the Reflotron, and 50 of 318 by more than 10% for the DT60. In general, the nurses were more adept at using the analysers than the physicians and medical office personnel. 相似文献
6.
Near-patient testing. Quality of laboratory test results obtained by non-technical personnel in a decentralized setting 总被引:1,自引:0,他引:1
The authors evaluated the quality and reliability of four desktop analyzers in the outpatient clinic. Twenty-seven nontechnologists (NTs) participated in the study. These included nurses, physicians, and medical students. The instruments and tests evaluated were as follows: Reflotron (glucose, cholesterol, triglycerides, gamma-glutamyltransferase and urea); Seralyzer (creatinine, glucose, potassium, aspartate aminotransferase, and hemoglobin); Vision (glucose, urea, cholesterol, triglycerides, alkaline phosphatase, and uric acid); and DT60 (sodium, potassium, glucose, amylase, uric acid, bilirubin, and creatinine). For precision studies, low and high control material was used, and method comparison was done with methods in routine use in the laboratory. The range of coefficients of variation (CVs) for the analyzers with NTs was as follows: Reflotron: CV, 2.4-7.9%; Seralyzer CV, 1.4-18.7%; Vision: CV, 1.5-2.7%; DT60: CV, 2.5-46.8. The percentage results that is different by greater than 10% between the NTs and trained technologists was related to the complexicity of procedure for each analyzer and was the lowest for the Vision analyzer and greatest for the Seralyzer. 相似文献
7.
Relationship between fatty liver and subsequent development of necrosis, inflammation and fibrosis in experimental alcoholic liver disease 总被引:4,自引:0,他引:4
Rats fed a diet varying in the amount of fat, infused with ethanol, were studied to determine the relationship among diet, degree of fatty liver, and development of necrosis, inflammation, and fibrosis. Three groups of experimental animals, male Wistar rats, were fed diets containing 25% fat, 35% fat, and 32% fat with low protein. Morphologic assessment of liver injury was performed monthly by obtaining liver biopsies. The greatest degree of fatty infiltration at 1 month was seen in the high fat-low protein group, the mean fat score (3.8 +/- 0.37) was significantly higher than in the other two groups (P less than 0.05 and P less than 0.01). When the subsequent development of necrosis, inflammation, and fibrosis was related to the degree of fatty infiltration at 1 month, a significant relationship was seen between the number of animals developing these pathologic lesions and the severity of fatty liver. Our results show that the degree of fatty infiltration of the liver, influenced by the dietary intake of both fat and protein, is related to the subsequent development of necrosis, inflammation, and fibrosis in our intragastric feeding model for alcoholic liver disease. 相似文献
8.
9.
Heavy alcohol consumption over long periods of time can result in severe liver damage, including death of liver cells (i.e., hepatocytes). Two mechanisms--apoptosis and necrosis--can contribute to hepatocyte death. In apoptosis, the affected cell actively participates in the cell death process, whereas in necrosis the cell death occurs in response to adverse conditions in the cell's environment. Numerous factors that may contribute to the initiation of hepatocyte apoptosis are affected by alcohol consumption. These factors include the enzyme cytochrome P450 2E1 (i.e., CYP2E1), small molecules (i.e., cytokines) involved in cell communication, oxidative stress, and changes in iron metabolism. Similarly, alcohol consumption can influence several factors believed to be involved in hepatocyte necrosis, including depletion of the energy-storing molecule adenosine-triphosphate, reduced oxygen levels (i.e., hypoxia) in the liver, oxidative stress, and bacterial molecules called endotoxins. 相似文献
10.
We report a case of severe aspiration pneumonitis in the dependent lung of a 74-yr-old man following Austin-Moore arthroplasty. A laryngeal mask airway provided a clear airway until anaesthesia became too light during manipulation of the fractured femoral head. Active vomiting occurred and gastric contents were "reflected" back into the trachea. Tracheal intubation and suction were immediately performed but the patient required postoperative ventilatory and inotropic support for three days. 相似文献