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101.
OBJECTIVE: To evaluate the effect of three different dosages of transdermally administered 17beta-estradiol on serum lipoproteins in women who had recently experienced surgical menopause. MATERIAL AND METHODS: We undertook a 2-year, randomized, double-blind, placebo-controlled study in which 126 subjects were recruited and stratified by age, and 93 patients completed the protocol. Serum lipoproteins were assessed before initiation of treatment and after 12 and 24 months of therapy with 0.025, 0.05, or 0.1 mg of estradiol daily. RESULTS: Total serum cholesterol and low-density lipoprotein cholesterol showed dose-dependent decreases that reached statistical significance after 2 years of treatment with transdermally administered estradiol. CONCLUSION: This study confirms that transdermally administered 17beta-estradiol has a modest beneficial effect on serum lipoproteins, with decreased levels of total cholesterol and low-density lipoprotein cholesterol. 相似文献
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Herein, we are describing an unusual case suffering from a left anterior cerebral artery aneurysm (A1). Both the anterior cerebral arteries were supplied by the left internal carotid artery as was found in digital substraction angiography (DSA) preoperatively. The postoperative angiograms revealed that left anterior cerebral artery was supplied from the left internal carotid artery and the right anterior cerebral artery by the right internal carotid artery respectively. This finding of cerebral angiograms is interesting and rarely mentioned in the literature. Its hemodynamic change and pathogenesis were unclear and different to that of the coronary circulation, ischemic change of gut and skeletal muscle. The causes may include: 1) vasospasm at the anterior communicating artery after manipulation at surgery; 2) desiccation or shrivelling the adjacent artery by intraoperative electrocoagulation; 3) occlusion the anterior communicating artery by the wing of clip. 4) the deprivation of the blood flow from the left internal carotid artery after totally or partially narrowing left A1 by an aneurysm clip. The redistribution of blood volume in the previously hypoplastic right anterior cerebral artery and decreased caliber of the left anterior cerebral artery (A1) are likely playing a role in this case. 相似文献
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Conventional joint replacements consist of a polished metallic or ceramic component articulating against a layer of polyethylene. Although the friction in the contact between these articulating surfaces is low, polyethylene wear is produced as a result of a boundary/mixed lubrication regime. Wear debris is generated by direct asperity contact, abrasion, adhesion and fatigue, and has been shown to cause adverse tissue reactions which can lead to joint failure. The introduction of soft compliant materials, similar in stiffness to articular cartilage, has shown that with cyclic loading and relative motion between the articulating surfaces typical of normal walking, a fluid film can be maintained through combined entraining and squeeze-film actions, and hence wear can be minimized. For 95 per cent of the time, however, we are not walking but standing still or moving slowly. A pendulum simulator has been used in the present study to investigate the effect of adverse tribological conditions which may lead to fluid film breakdown, such as severe cyclic loading, particularly in the swing phase, reduced sliding velocity, reduced stroke length and start-up after a period of constant loading. Friction of a model composite cushion knee bearing, manufactured from a graded modulus (20-1000 MPa) layer of polyurethane, sliding against a polished metal cylinder has been measured for various lubricants and the results have been analysed using a Stribeck assessment. Severe cyclic loading, decreased sliding velocity and decreased stroke length have been found to limit the degree of fluid entrainment previously allowed during the swing phase of normal walking, thus allowing breakdown of fluid films and elevated levels of friction and surface damage. Soft layer joint replacements must therefore be designed to operate with thick elastohydrodynamic fluid films to provide some degree of protection when tribological conditions become severe, or alternatively incorporate alternative boundary or mixed lubrication mechanisms. This study quantifies a potential limitation of the cushion bearing concept. 相似文献
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ZM Quezado C Natanson DW Alling SM Banks CA Koev RJ Elin JM Hosseini JD Bacher RL Danner WD Hoffman 《Canadian Metallurgical Quarterly》1993,269(17):2221-2227
OBJECTIVE: To investigate the therapeutic efficacy and microbiological and physiological effects of a human IgM monoclonal antibody (HA-1A) directed against the lipid A component of endotoxin in a canine model of sepsis that simulates the cardiovascular abnormalities of human septic shock. DESIGN: Blinded, placebo-controlled 28-day trial. INTERVENTIONS: Purpose-bred beagles were implanted with an intraperitoneal clot infected with Escherichia coli O111:B4. At clot placement, animals received HA-1A (10 mg.kg-1), control human IgM antibody (10 mg.kg-1), or control human serum albumin intravenously. All animals were given antibiotic and fluid therapy. MEASURES: Survival and microbiological and physiological events. RESULTS: Only two (15%) of 13 animals in the HA-1A group, compared with eight (57%) of 14 control animals (combined control human IgM antibody and control human serum albumin groups) (P = .05), survived 28 days. At 24 hours, the HA-1A group had lower mean arterial pressure (P = .04) and cardiac index (P = .004) and higher lactate levels (P = .05) compared with the combined-controls group. In addition, these parameters in the HA-1A group were significantly more predictive of death. The HA-1A and combined-controls groups had similar significant increases in the level of endotoxemia and bacteremia. Studies of toxic effects showed no harmful effects of control human IgM antibody in infected animals or HA-1A in non-infected animals. CONCLUSION: In a canine model of E coli sepsis, HA-1A did not alter levels of bacteremia or endotoxemia and actually decreased survival. If these data are relevant to human septic shock, HA-1A therapy should be limited until the conditions under which this monoclonal antibody has beneficial or deleterious effects are more completely defined. 相似文献
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ZM Rupniewska 《Canadian Metallurgical Quarterly》1996,96(5):419-426
The typical MRI features of the most common pancreatic diseases, such as pancreatitis and adenocarcinoma of the pancreas, have been established. However, even in these common pancreatic disorders, MRI correlation with the underlying pathology is limited for clinical reasons. We emphasize MR-pathological correlation of inflammatory and neoplastic pancreatic changes, including pancreatitis, adenocarcinoma, acinar cell carcinoma, rare cystic and solid pancreatic neoplasms, and islet cell tumors. By highlighting the correlation of key pathological features with MR findings, a better understanding of the MR appearance of pancreatic pathology can be provided. In addition, MRI may prove a powerful tool in detection and characterization of pancreatic tumors. 相似文献
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BM Prenner P Chervinsky FC Hampel WC Howland M Lawrence EO Meltzer ZM Munk PH Ratner JM Seltzer GA Settipane RR Lorber JE Harrison 《Canadian Metallurgical Quarterly》1996,98(2):302-308
Determination of microgram quantities of protein in the Bradford Coomassie brilliant blue assay is accomplished by measurement of absorbance at 590 nm. However, as intrinsic nonlinearity compromises the sensitivity and accuracy of this method. It is shown that under standard assay conditions, the ratio of the absorbances, 590 nm over 450 nm, is strictly linear with protein concentration. This simple procedure increases the accuracy and improves the sensitivity of the assay about 10-fold, permitting quantitation down to 50 ng of bovine serum albumin. Furthermore, protein assay in presence of up to 35-fold weight excess of sodium dodecyl sulfate (detergent) over bovine serum albumin (protein) can be performed. A linear equation that perfectly fits the experimental data is provided on the basis of mass action and Beer's law. 相似文献
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