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51.
A breakthrough in platelet inhibition was achieved with the advent of antagonists of the glycoprotein (GP) IIb/IIIa receptors. These receptors are essential to platelet aggregation triggered by any of several different mechanisms. GP IIb/IIIa receptor antagonists, especially the monoclonal antibody abciximab, have been established as adjuncts to angioplasty in acute coronary syndromes. Conjunctive treatment with thrombolysis in myocardial infarction has been studied less extensively. GP IIb/IIIa receptor antagonists appear to be a feasible adjunct to thrombolysis. In particular, the use of abciximab in conjunction with reduced doses of thrombolytics is an attractive approach to achieve early coronary reperfusion with probably acceptable bleeding risk. The eventual role of this combined treatment can only be defined by the large-scale clinical trials that will be performed in the near future.  相似文献   
52.
Based on the hypothesis that a synergistic interaction between triiodothyronine (T(3)) and insulin contributes to abnormalities in glucose and other metabolic pathways, the mechanisms underlying the impairment of metabolic homeostasis (MH) and the development of type-2 diabetes (DM) were investigated via a proposed homeostatic model, [(FG*TG)/T3*FI)]. The MH model characterizes the relationship between T(3) and insulin and the levels of triglycerides (TG), fasting insulin (FI), and fasting glucose (FG) and is introduced as a clinical method to assess insulin sensitivity and the status of metabolic homeostasis in lieu of current screening models advocated by the by American Diabetic Association (ADA). The present study validated the hypothetical model in a sample of 110 African-American women.  相似文献   
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Zusammenfassung Der Fall eines Myoepithelioms des tiefen Weichgewebes wird mit klinisch-pathologischen, ultrastrukturellen und genetischen Befunden vorgestellt. Bei einem 30-jährigen Patienten fand sich ein Weichgewebstumor am rechten Unterschenkel innerhalb der tiefen Wadenmuskulatur mit Ausmaßen von 13,2x8,2x9 cm. Histologisch lagen Strukturen eines Myoepithelioms mit lobulärer, teils trabekulärer und nestartiger Lagerung der blanden epitheloiden und spindeligen Tumorzellen in einer fibromyxoiden, teils chondroiden Matrix vor mit immunhistochemischer Expression von Panzytokeratinen, S100-Protein sowie Calponin, fokal auch GFAP und EMA. Ultrastrukturell fanden sich Glykogeneinlagerungen und subplasmalemmale Verdichtungsstrukturen, wobei eindeutige Myofilamente nicht zu sichern waren (bei immunhistochemisch fehlender Aktinexpression). Mit Hilfe der komparativen genomischen Hybridisierung (CGH) konnte ein Zugewinn am Y-Chromosom nachgewiesen werden. Ein 17p-Verlust war zwar nicht eindeutig zu detektieren, kann aber bei der geringen Auflösung der CGH auch nicht ausgeschlossen werden. Der Patient war 25 Monate nach vollständiger Tumorresektion krankheitsfrei.Myoepitheliome bzw. Mischtumoren des Weichgewebes stellen seltene Weichgewebsneoplasien dar, die — wie im dargestellten Fall — eine erhebliche Größe erreichen können und andere Weichgewebstumoren oder -sarkome klinisch-radiologisch imitieren können. Bei einer Lokalrezidivrate von 20% nach Angaben der Literatur ist eine vollständige chirurgische Entfernung mit Nachbeobachtung zu empfehlen.Gewidmet Herrn Dr. Heinrich Dickmans.  相似文献   
55.
Coinfection of chicken embryo fibroblasts with reticuloendotheliosis virus (REV) and avian sarcoma virus leads to the formation of avian sarcoma viral pseudotypes which carry envelope determinants of REV. These pseudotypes can be neutralized by REV antiserum, have a host range which is different from that of any known avian sarcoma virus, and are unable to form foci in cells preinfected with REV. The REV stocks used in these experiments were plaque-purified. They were free of avian leukosis virus detectable in the COFAL tests, and their ability to form pseudotypes with avian sarcoma virus was neutralized with specific REV antiserum.  相似文献   
56.
The advent of SAL (suction-assisted lipectomy) has dramatically increased the number of obese patients coming to our consultation offices. Despite several articles suggesting a conservative approach to fat suction, some reports insinuate that SAL might be a useful tool for obesity treatment. This hypothesis is refuted by a vast body of evidence that concludes that the adipose tissue may regenerate in adult humans. Therefore, surgical procedures are not advised as the method of choice to manage the disease. On the other hand, the terms obesity and being overweight may not be interchangeable. Obesity may be a disease whereas being overweight is asign of the disease. Consequently, proper preoperative selection of candidates for SAL becomes mandatory. The hCG (human chorionic gonadotropin) method for obesity treatment appears to be a complete program for the management of obesity. It contains pharmacologic, dietetic, and behavior modification aspects in a 40-day course of treatment. Some data suggest hCG to be lipolytic, thus explaining former clinical observations regarding body fat redistribution in treated patients. hCG commercial preparations contain -endorphin, an opioid peptide linked to mood behavior. This article speculates on the possible actions of the complex hCG -endorphin in the neuromodulation of mood and energy metabolism. The method comprises a behavior modification that helps in handling the patient better. There are some correlations between a current behavior modification program and the basic guidelines contained in the hCG protocol. Thus, the hCG method appears to be a reasonable alternative in the management of a long-standing, unsolved problem of human metabolism.  相似文献   
57.
The authors obtained and evaluated antisera from rabbits injected with a derivative of a potent bladder carcinogen, dichlorobenzidine (DCB), conjugated to bovine serum albumin (BSA). A 14C-radioimmunoassay (RIA) was able to detect the presence of DCB antibodies, but its relative insensitivity led to the development of a more sensitive enzyme immunoassay (EIA). The EIA test was a "sandwich" method in which a second antibody, labeled with an enzyme (horseradish peroxidase), was used to measure antibody binding to transferrin (Tf)-conjugated DCB immobilized on a microtiter plate. Antibody titers measured by RIA were approximately 1:40; when measured by EIA, they were approximately 1:40,000. Antibody specificity was assessed by comparing the antibody binding activities of DCB, BSA, Tf, BSA-conjugated to DCB, and a number of N-substituted aromatic compounds that included benzidine (Bz). Among the compounds tested, the rabbit antiserum reacted only with DCB and the carrier protein, BSA. Moreover, antibody binding activity to Tf-conjugated DCB was significantly inhibited by unconjugated DCB concentrations between 30 and 500 ng/mL. The precision of antibody binding activities as a function of DCB concentration (expressed by the CV) ranged from 9% for low (30 ng/mL) DCB levels to 12% for higher (500 ng/mL) levels. This evaluation suggests that the antiserum obtained would be appropriate for detecting DCB levels at the ng/mL level.  相似文献   
58.
59.
While vascular endothelial cells are repeatedly stretched by the pulsatile nature of cardiac output, in vitro models traditionally used to study vascular biology involve static culture techniques. We have recently shown that pulsatile stretching of endothelial cells in culture will increase their rates of proliferation and regulate their secretion of macromolecules. The aim of this study was to determine whether membrane adenylate cyclase is involved in intracellular signalling during pulsatile stress. Bovine aortic endothelial cells were seeded on flexible-bottomed culture wells (3 x 10(5) cells/25 mm well) and allowed to attach for 48 hours. The culture wells were placed in a vacuum-operated stress providing instrument and subjected to 0.5 s of 24% strain, 0.5 s relaxation (60 cycles/min) for 0, 1, 3, 5, 7, 10 and 15 minutes (N = 24 wells/time point). Cells were homogenized and a crude membrane preparation (27,000 x g) was assayed for adenylate cyclase under basal and forskolin (100 microM) stimulated conditions. The results indicate that there is a time-dependent increase in both basal and stimulated adenylate cyclase with cyclic deformation and suggest that there may be a "stretch receptor" coupled to adenylate cyclase which can modulate endothelial cell function with hemodynamic changes.  相似文献   
60.
Attempts to predict the degree of pulmonary hypoplasia associated with congenital diaphragmatic hernia have been made by evaluating the ventilation parameters and the arterial blood gasses of these patients. A CO2 index as a predictor of outcome, which correlates the PaCO2 with the ventilation index, was recently proposed. However, in this study the postductal PaO2 was a better predictor of survival. And the so-called "honeymoon period" was a better indicator of the efficacy of extracorporeal membrane oxygenation (ECMO) than the CO2 index. Nineteen patients were evaluated; 11 were treated with ECMO, and eight were not considered suitable for ECMO.  相似文献   
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