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The ability of native and oxidized lipids and lipoproteins to stimulate production of reactive oxygen species (ROS; superoxide and hydrogen peroxide) by human blood monocytes has been studied in vitro. Neither native human low density lipoprotein (LDL), ''altered'' LDL (oxidized either by lipoxygenase, activated human monocytes or air) nor oxidized cholesterol had any significant effect on ROS production of monocytes. However, different oxidation products of a lipid emulsion (Lipofundin; largely consisting of linoleic acid oxidized either by lipoxygenase, Fe3+ or ultraviolet irradiation) greatly enhanced ROS production of monocytes. A hypothesis that activation of circulating leucocytes by oxidized fatty acids may generate oxidized plasma LDL, was tested in rabbits. Characteristics of LDL, separated from rabbit plasma 6 h after intravenous injection of an oxidized lipid emulsion, was compared to that of LDL isolated before the lipid treatment. Post-treatment LDL-fraction of plasma had increased lipid peroxide content and compared to the pretreatment LDL, caused a threefold increase in the incorporation of cholesterol into cultured (rat aortic) endothelial cells. The observed intense and lasting stimulation of monocytes by oxidized polyunsaturated fatty acids in vitro, and the generation of ''altered'' LDL by these oxidized lipids in vivo suggests a mechanism by which atherogenic oxidized LDL could form in the circulation.  相似文献   
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Zusammenfassung Die bogenförmige ST-Strecke kommt häufig, in etwa 12%der Fälle, und die Zwischenzacke selten, in 5der Fälle eines nichtausgewählten Krankenmaterials, vor. Sowohl die Entstehungsursache der bogenförmigen ST-Strecke als der Kischschen Zwischenzacke liegt in der stärkeren oder schwächeren Rechts- oder Linksdeviation der S-Achse. Die Richtung und der Grad der S-Achsendeviation wird es also bestimmen, in wie vielen und welcher Einthovenschen Ableitung die bogenförmige ST-Strecke bzw. die Zwischenzacke notwendigerweise auftreten muß. Bei S-Achsenstellungen zwischen –90°und –30°wird die ST-Strecke in Ableitung I, bei S-Achsenstellungen zwischen –30°und +30°in der I. und II., zwischen +30°und +90°in der I., II., III., zwischen +90°und +150°in der II., III. und bei den Achsenstellungen zwischen +150°und –150°in der III. Einthovenschen Ableitung bogenförmig sein. Die klinische Bedeutung der bogenförmigen ST-Strecke ist gleich mit der klinischen Bedeutung der S-Achsendeviation. Bei dem Vergleich des Herzbefundes der Kranken mit der elektrischen S-Achsenstellung können folgende Feststellungen gemacht werden: Geringergradige Linksdeviation der S-Achse, d. h. bogenförmiges ST I sowie geringergradige Rechtsdeviation der S-Achse, d. h. STIII kann praktisch bei pathologischem Herzbefund nicht verwertet werden. Stärkere Links- bzw. Rechtsdeviation der S-Achse, d. h. STI undII bzw. STII undIII können im allgemeinen ebenfalls nicht verwertet werden, es ist jedoch wahrscheinlich, daß sie schon einen Übergang zu den pathologischen Befunden bilden. Während jene starken S-Achsendeviationen, wo schon in allen drei Ableitungen bogenförmiges ST besteht, meistens für das Zeichen der myokardialen Läsion betrachtet werden sollen, und zwar in erster Linie dann, wenn die positive S-Zacke in oder neben dem absteigenden Schenkel der R-Zacke gut wahrnehmbar ist.  相似文献   
96.
Abstract  Upper gastrointestinal (GI) symptoms occur frequently in the general population, making them among the most common indications responsible for patients consulting the healthcare system. Consequently, understanding and characterization of the upper GI symptoms is important for the diagnosis and assessment of organ dysfunction. In practice, assessment of clinical symptoms is difficult and it is still to a large extent unclear how sensitivity, volume and tone contribute to visceral perception in the upper GI tract. The goal of advanced research in upper GI symptoms is to obtain a better understanding of the mechanisms involved in transduction, transmission, and perception under normal and pathophysiological conditions. An important step towards this goal is understanding the information provided by and the inherent limitations of the currently available measuring techniques. This article focuses on the sensory testing of the oesophagus, and methods and concepts used to assess the relation between gastric volumes or tone and upper GI symptoms. It also summarizes the contributions of these techniques towards identifying the components responsible for the generation of upper GI symptoms.  相似文献   
97.
AIMS: The aims of our study were to determine if insulin resistance is associated with increased plasma levels of non-esterified fatty acids (NEFA), glycerol, 3-hydroxybutyrate and triglycerides in obese children. We also studied whether the presence of acanthosis nigricans (AN) led to further alterations in the above parameters. METHODS: A total of 101 children were studied on their first visit to the paediatric endocrine clinic. Seventy-four were obese, 30 of them with AN. The remaining 27 were non-obese healthy children (control group). NEFAs, glycerol, triglycerides, 3-hydroxybutyrate, insulin, leptin, adiponectin and glucose were determined in blood samples obtained after overnight fasting. The insulin resistance index (IRI) was calculated following the homeostasis model assessment (HOMA). Data from the three groups were compared using appropriate statistical tests. RESULTS: No differences in age, sex ratio and pubertal stage were observed among the three groups. The group of children with the highest body mass index (BMI) showed higher plasma levels of insulin and leptin, higher IRI and lower plasma levels of adiponectin. As insulin and IRI increased, NEFA and 3-hydroxybutyrate decreased and triglycerides increased. When obese children were categorized by BMI, the presence of AN further exacerbated these differences. CONCLUSIONS: In obese children, insulin resistance is associated with plasma lipid alterations suggestive of both decreased adipose tissue lipolysis and hepatic beta-oxidation and increased hepatic synthesis of triglycerides. Such a metabolic condition may facilitate fat storage and hinder weight loss.  相似文献   
98.
BACKGROUND: Clinical benefit from extended lymphadenectomy for gastric cancer remains controversial as a considerable variation exists between results of different studies. METHODS: 562 patients were treated at HUCH between 1987-2003, whereof 223 underwent gastrectomy with curative intent. Of these, 114 patients underwent subtotal/total gastrectomy with D1 (standard) lymphadenectomy and 109 patients had D2-3 (extended) lymph node dissection. The clinical outcome of these patients was analysed retrospectively. RESULTS: The incidence of surgical complications was 33.0% in D2-3 and 16.8% in D1 lymphadenectomy groups (p = 0.008). Abscess was the most common complication (11.0%) among D2-3 operated patients and haemorrhage (4.4%) in D1 group. Hospital mortality was 3.7% in D2-3 and 1.8% in D1 group (p = 0.438). The only statistically significant factor influencing the rate of complications was D2-3 lymphadenectomy (OR 2.620, 95% C.I. 1.375 to 4.991). D2-3 was associated with a longer postoperative hospital stay and operation time, greater blood loss and increased need for blood transfusions compared to D1. The 5-year survival was not statistically different between lymphadenectomy groups. CONCLUSION: It is justified to perform a D2-3 gastrectomy in Europe with a acceptable postoperative mortality but with a significant morbidity. Further studies are needed to assess the value of extended lymphadenectomy in gastric cancer.  相似文献   
99.
Hepatic encephalopathy is a reversible state of altered cognition that may occur in patients with acute or chronic liver disease or porto-systemic shunt, and in which known neurological or psychiatric signs may develop. Nitrogenated substances from intestinal digestion reach the brain without being cleared by their passage through the liver due to the presence of porto-systemic shunt. We report two cases of patients with porto-systemic shunt diagnosed with recurrent chronic hepatic encephalopathy refractory to conventional medical treatment. They were satisfactorily treated with shunt embolization using interventionist radiology techniques.  相似文献   
100.
Five patients with idiopathic transient osteoporosis were examined. Bone scanning and MRI was helpful in the diagnosis to differentiate of necrosis and all patients recovered completely with conservative and symptomatic treatment. There was no history of trauma in all patients. MRI was realized previously in all cases to confirm the diagnosis and after the resolution of symptomathology.  相似文献   
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