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91.
The deaths of 10 heroin body packers are reported and contrasted to those of cocaine body packers. Only one was a woman, and all were traveling to or from Colombia. Drug packets deteriorated in the gastrointestinal tract and caused the deaths of eight victims. Accomplices removed drug packets from two of these smugglers after death occurred. One died of peritonitis stemming from a small-bowel obstruction caused by the drug packets, and one died from the recreational use of heroin (nasally ingested). The heroin recovered was < or = 881 g, and the drug purity of the contraband in three cases was between 65% and 73%. Blood concentrations of morphine were < 1.0 mg/L in four victims; no morphine was detected in the smuggler who died of peritonitis. However, two victims had blood morphine concentrations of 4.4 mg/L and 6.7 mg/L, respectively, and three had morphine concentrations of 35.8, 39.4, and 52.6 mg/L, respectively. Fatal heroin body packing differs from cocaine body packing in that individuals may have extremely high drug levels in their blood and their accomplices appear to be more likely to abandon them in a remote location after attempting to remove the drug packets after death has occurred.  相似文献   
92.
93.
Melorheostosis is a very rare bone disease of unknown etiology characterised by linear hyperostosis and associated with fibrosis of soft tissues and the skin. This uncommon sclerosing bone dysplasia was first described by Leri and Joanny in 1922, and since then, until 1993, approximately 300 cases were reported in the literature. Linear scleroderma is a localised proliferation of connective tissue and has rarely been associated with melorheostosis. In this paper, we present a new case of melorheostosis with linear scleroderma which, to the best of our knowledge, is the first case reported in Turkey.  相似文献   
94.
Early fatty streaks and advanced lesions are characterized by the deposition of cholesterol and cholesterol oxidation products (oxysterols). Oxysterols have been shown to be cytotoxic and pro-atherogenic compared to cholesterol and are found in cholesterol-rich processed foods. The consumption of dietary oxysterols may be significant in the onset and development of vascular disease. In order to study the short term effects of low levels of ingested dietary oxysterols on lipoprotein and aortic cholesterol and oxysterol levels, rabbits were fed either standard chow, chow supplemented with 1.0% oxidized cholesterol (containing 6% oxysterols), or 1.0% purified cholesterol (control). To determine the distribution and uptake of oxysterols after a 2-week dietary period, triglyceride-rich plasma lipoproteins, low density lipoproteins and aorta were analyzed by GC-MS. The concentration of 7beta-hydroxycholesterol was similar in all groups but the oxidized cholesterol-fed animals showed five times the concentration of 5alpha,6alpha-epoxycholesterol and double the level of 7-ketocholesterol in triglyceride-rich lipoproteins compared to the purified cholesterol-fed animals. The presence of 7-ketocholesterol in LDL was exclusive to animals fed the oxidized cholesterol diet. In addition, oxidation of triglyceride-rich lipoproteins was significantly greater in rabbits fed oxidized cholesterol compared to the pure cholesterol-fed animals. The oxidized cholesterol-fed animals also had a 64% increase in total aortic cholesterol, despite lower plasma cholesterol levels compared to the pure cholesterol control animals. Taken together these results suggest that dietary oxysterols may substantially increase the atherogenicity of lipoproteins.  相似文献   
95.
To elucidate cellular mechanisms of insulin resistance induced by excess dietary fat, we studied conscious chronically high-fat-fed (HFF) and control chow diet-fed rats during euglycemic-hyperinsulinemic (560 pmol/l plasma insulin) clamps. Compared with chow diet feeding, fat feeding significantly impaired insulin action (reduced whole body glucose disposal rate, reduced skeletal muscle glucose metabolism, and decreased insulin suppressibility of hepatic glucose production [HGP]). In HFF rats, hyperinsulinemia significantly suppressed circulating free fatty acids but not the intracellular availability of fatty acid in skeletal muscle (long chain fatty acyl-CoA esters remained at 230% above control levels). In HFF animals, acute blockade of beta-oxidation using etomoxir increased insulin-stimulated muscle glucose uptake, via a selective increase in the component directed to glycolysis, but did not reverse the defect in net glycogen synthesis or glycogen synthase. In clamp HFF animals, etomoxir did not significantly alter the reduced ability of insulin to suppress HGP, but induced substantial depletion of hepatic glycogen content. This implied that gluconeogenesis was reduced by inhibition of hepatic fatty acid oxidation and that an alternative mechanism was involved in the elevated HGP in HFF rats. Evidence was then obtained suggesting that this involves a reduction in hepatic glucokinase (GK) activity and an inability of insulin to acutely lower glucose-6-phosphatase (G-6-Pase) activity. Overall, a 76% increase in the activity ratio G-6-Pase/GK was observed, which would favor net hepatic glucose release and elevated HGP in HFF rats. Thus in the insulin-resistant HFF rat 1) acute hyperinsulinemia fails to quench elevated muscle and liver lipid availability, 2) elevated lipid oxidation opposes insulin stimulation of muscle glucose oxidation (perhaps via the glucose-fatty acid cycle) and suppression of hepatic gluconeogenesis, and 3) mechanisms of impaired insulin-stimulated glucose storage and HGP suppressibility are not dependent on concomitant lipid oxidation; in the case of HGP we provide evidence for pivotal involvement of G-6-Pase and GK in the regulation of HGP by insulin, independent of the glucose source.  相似文献   
96.
A technique for studying the catalytic activity of enzymes spread as a film at an air-water interface, by exchanging the subphase under the film to remove unspread enzyme molecules, was developed, and its effectiveness was studied using surface-spread mitochondrial malate dehydrogenase. Mitochondrial malate dehydrogenase formed stable films which gave reproducible pi-A curves. The enzyme activity was measured by the oxidation rate of reduced nicotinamide adenine dinucleotide (NADH) in the presence of the substrate oxalacetic acid. Oxalacetic acid and NADH were injected into the subphase. The catalytic activity of the enzyme was dependent on the surface pressure of the film. The maximum catalytic activity was observed at a surface pressure of 4.4 dynes/cm. The activity was higher at intermediate surface pressures than at very low or very high surface pressures. A high bulk catalytic activity was observed in the unstable region, i.e., at a high degree of compression, of the film. The catalytic activity of the surface-spread enzyme was only a fraction of an equivalent amount of enzyme in solution.  相似文献   
97.
The families of 26 patients with Ebstein's anomaly were examined. There were 120 first-degree relatives, 100 of whom were living, and 93 of these were examined. Information was available on 14 of the 20 who had died. No case of Ebstein's anomaly was found among the first-degree relatives, but 2 had ventricular septal defects and another, who died at 7 months, was said to have had congenital heart disease. In more distant relatives there were 6 with congenital heart disease, including 2 with ventricular septal defects and 2 with Fallot's tetralogy.  相似文献   
98.
99.
The ability of macrophages of phagocytize particulate matter is largely dependent on fibronectin, a nonspecific opsonin found in plasma. Fibronectin depletion, resulting in reticuloendothelial system (RES) depression, occurs following a variety of physical insults. RES depression may contribute to postinjury sequelae such as respiratory distress syndrome and septicemia. Fibronectin concentration was measured in the plasma of sheep with chronic lung lymph fistulas subjected to controlled thermal injury. Fibronectin levels were significantly (p < 0.05) decreased at 4, 24, 48, and 72 hours following burning. Fibronectin concentration decreased in parallel with serum albumin concentration; serum globulin concentrations did not decrease. Fibronectin concentration had an inverse relationship to lung lymph flow, a reflection of pulmonary transvascular fluid filtration rate. The role of fibronectin in the pathogenesis of postinjury respiratory distress syndrome deserves further exploration.  相似文献   
100.
The effects of chemico-physical growth conditions such as pH, temperature and water activity (aw) on lethal high homogenization pressure effects on Listeria monocytogenes, Staphylococcus aureus, Escherichia coli and Yarrowia lipolytica were investigated. The results, though based on standard media, emphasize the importance of food system composition and its thermal history on the high pressure tolerance of the microbial population.  相似文献   
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