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61.
Despite some evidence of the involvement of the serotonergic system in cluster headache (CH) pathophysiology, the serotonin (5HT) metabolism has so far been poorly studied. The aim of this study was to investigate plasma and platelet levels of 5HT and 5-hydroxyindoleacetic acid (5HIAA) in CH patients in the active period of the disease. Nineteen CH sufferers and 17 sex- and age-matched healthy controls were studied. CH patients showed significantly higher plasma levels of 5HT and 5HIAA compared to controls (5HT: 5.7±6.1 ng/ml vs 0.2±0.2 ng/ml; p =0.02; 5HIAA: 34.7±46.1 ng/ml vs 0.6±0.7 ng/ml; p =0.004). In platelet 5HT levels were slightly reduced in CH patients in comparison with those of control subjects (662.4±522.3 ng/10−8 platelets vs 832.1±587.9 ng/10−8 platelets; n.s.) and 5HIAA levels resulted significantly lower in CH sufferers than in control subjects (3.2±2.6 ng/10−8 platelets vs 6.7±4.8 ng/10−8 platelets; p =0.04). Our data suggest that CH is characterized by an increase of plasma serotonergic metabolism that could reflect an involvement of the central serotonergic system in the pathogenesis of CH.  相似文献   
62.
Increased emphasis on strict glycaemic control of insulin dependent diabetes mellitus (IDDM) in young patients may be expected to cause increases in rates of significant hypoglycaemia. To evaluate whether this is the case for a large population based sample of IDDM children and adolescents rates of severe (coma, convulsion) and moderate (requiring assistance for treatment) hypoglycaemia were studied prospectively over a four year period. A total of 709 patients were studied yielding 2027 patient years of data (mean (SD) age: 12.3 (4.4); range 0-18 years, duration IDDM: 4.9 (3.8) years). Details of hypoglycaemia were recorded at clinic visits every three months when glycated haemoglobin (HbA1c) was also measured. Overall the incidence of severe hypoglycaemia was 7.8 and moderate was 15.4 episodes/100 patient years. Over the four years mean (SD) clinic HbA1c steadily fell from 10.2 (1.6)% in 1992 to 8.8 (1.5)% in 1995. In parallel with this there was a dramatic increase in the rate of hypoglycaemia, especially in the fourth year of the study, when severe hypoglycaemia increased from 4.8 to 15.6 episodes/100 patient years. This increase was particularly marked in younger children (< 6 years) in whom severe hypoglycaemia increased from 14.9 to 42.1 episodes/100 patient years in 1995. It is concluded that attempts to achieve improved metabolic control must be accompanied by efforts to minimise the effects of significant hypoglycaemia, particularly in the younger age group.  相似文献   
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Résumé: Malgré une incidence croissante du cancer du sein dans la population agée, les données spécifiques prospectives concernant sa prise en charge après 70 ans, tout particulièrement pour les indications de chimiothérapie adjuvante, sont rares dans la littérature, gênant l’application de recommandations standards établies essentiellement chez les sujets plus jeunes. La plupart des données dérivent d’essais multicentriques ayant étendu l’age limite supérieur d’inclusion à 65 ou 70 ans. Un seul essai multicentrique, fran?ais, a spécifiquement abordéle r?le d’une chimiothérapie adjuvante à base d’anthracyclines ajoutée au tamoxifène chez le sujet de plus de 65 ans. Pourtant plusieurs revues rétrospectives de groupes coopérateurs internationaux semblent démontrer lemame béneéfice potentiel d’une chimiothérapie adjuvante chez les sujets agés que chez les sujets plus jeunes, sous réserve d’une vigilance accrue à l’égard des effets secondaires. Avec l’aide ajustée d’échelles spécifiques gériatriques, les cliniciens doivent apprendre à intégrer bénéfice absolu, espérance de vie et tolérance, trois volets essentiels pour abandonner la discrimination ancienne reposant sur l’age, inadaptée à l’évolution de nos moyens et pratiques.   相似文献   
66.
Blood transfusion costs: a multicenter study   总被引:5,自引:0,他引:5  
The cost of delivering a unit of blood (whole blood or red cells) to a hospitalized patient was examined in 19 United States teaching hospitals. The average hospital acquisition cost was calculated by using the prices charged by regional blood centers for blood products. To this cost was added an estimate of costs incurred by hospitals for handling, testing, and administering blood. Across study sites, the average hospital cost per unit transfused was $155 and the average charge to the patient was $219. Acquisition cost, the price that hospitals pay for blood, was 37 percent of the total cost to the hospital; the other 63 percent of the hospital cost included costs for blood bank handling (13%), laboratory tests (43%), and blood administration (7%). Significant variations in blood transfusion cost were found within our sample. Most of the variability can be attributed to geographic location of the blood supply source, type of red cell product transfused, prices charged by blood transfusion services, and the frequency of laboratory tests. The results of this transfusion cost study may be helpful in determining the costs of health care delivery, especially when blood transfusions are indicated.  相似文献   
67.
Antihypertensive drugs slow the progressive decline in renal function seen in patients with insulin-dependent diabetes and nephropathy. In a recent study, the ACE inhibitor captopril protected against this deterioration in renal function. We developed an economic model to analyse the cost impact of ACE inhibitor treatment on progression to endstage renal failure (ESRF) in diabetic patients over 4 years. Two scenarios were compared: one describing the progression of a cohort of 1000 patients receiving 25 mg captopril three times daily, and the other for an equivalent cohort without such prophylactic treatment. Previously published data were used to estimate the transition rates for each stage from the onset of renal failure until death. All direct costs were discounted by an annual rate of 6%, and were subjected to sensitivity analysis. The discounted cost saving of ACE inhibitor treatment for a cohort of 1000 patients was estimated as 0.95 million pounds over 4 years. Under sensitivity analysis, these results were very robust to variations in the costs of ESRF treatment. Prophylactic treatment with ACE inhibitors was predicted to provide substantial increases in life expectancy and reduction in the incidence of ESRF, while also providing significant economic savings.   相似文献   
68.
目的:观察电针对单纯性肥胖大鼠下丘脑瘦素和神经肽Y表达的影响,探索电针减肥的机制。方法:实验于2005-12/2006-06在中南大学湘雅医院中西医结合研究所实验室完成。①取1月龄刚断乳SD雄性大鼠,随机取6只饲以普通饲料为正常对照组,其他大鼠饲以高脂饲料,喂养3个月后,选择体质量超过正常对照组20%的单纯性肥胖大鼠12只,随机分为模型组和电针组2组,每组6只。②电针组大鼠电针双侧足三里、天枢、三阴交穴,采用疏密波,电流强度0.3~0.6mA,留针20min,1次/d,共20次;其他2组不电针。实验期间均饲以普通饲料。③观察实验大鼠体质量、体长、Lee's指数及体脂,采用Western-blot技术检测下丘脑组织中瘦素、神经肽Y表达的变化。结果:18只大鼠进入结果分析。①模型组大鼠体质量和Lee’s指数高于正常对照组[(451.8±14.8),(323.6±6.8)g;324.25±1.4,305.14±1.5;P均<0.01];电针组电针后体质量和Lee’s指数低于电针前[(372.2±20.4),(454.7±19.7)g;307.71±1.5,323.56±1.6;P均<0.01]。②模型组大鼠心包、肾周和附睾脂肪量均高于正常对照组(P<0.01);电针组电针后心包、肾周和附睾脂肪量低于电针前(P<0.01)。③模型组下丘脑组织中瘦素蛋白表达低于正常对照组(0.62±0.11,0.88±0.15,P<0.01),电针组高于模型组(0.85±0.13,P<0.01);模型组下丘脑组织中神经肽蛋白表达高于正常对照组(2.42±0.27,1.75±0.24,P<0.01),电针组高于模型组(1.87±0.21,P<0.01)。结论:电针有良好的减肥效果,其作用可能与电针增强下丘脑组织瘦素蛋白的表达、同时抑制下丘脑组织中的神经肽Y蛋白表达有关。  相似文献   
69.
Seven patients with high-risk acute T-cell lymphoblastic leukemia (T- ALL) and six with T cell lymphoma (T-LL) were treated with autologous bone marrow transplantation (ABMT) after in vitro purging of their bone marrow with WT1 (CD7)-ricin A-chain immunotoxin. CD7 expression on the tumor cells showed large variations between the individual patients and was highly related to the specific cytotoxicity of WT1-ricin A. Incubation of bone marrow with up to 10(-8)mol/L WT1-ricin A in the presence of 6 mmol/L NH4Cl did not compromise the growth potential of the hematopoietic progenitors CFU-GM, CFU-GEMM, and BFU-E. Hematologic engraftment (greater than 10(9) leukocytes/L) occurred within a normal time period (median, 17 days). Seven patients are alive and in complete remission (CR) at 48+, 44+, 40+, 26+, 11+, 7+, and 6+ months after ABMT. Four patients relapsed within 6 months after ABMT. Two of them had the lowest CD7 expression on their tumor cells, the other two were transplanted in CR2 and CR3. Two patients died from transplantation related infections. The immunologic reconstitution was delayed, although the numbers of T cells reached normal levels within 1 month. The number of CD7+ cells remained low up to 1 year after transplantation. The T4/T8-ratio was decreased for at least 6 months. The T-cell response to mitogens recovered to normal levels after 1 year. This study shows that ABMT with WT1-ricin A purged bone marrow in high-risk T-cell malignancies results in a complete hematopoietic and a delayed immunologic reconstitution. The actuarial relapse free survival is 61% at 3 years.  相似文献   
70.
Previous studies have shown that human endothelial cells (ECs) adhere to fibrinogen (fg) and fibronectin (fn) and organize their cytoskeleton on these substrata. However, the mechanism governing this chain of events is poorly known. In ECs glycoproteins immunologically and biochemically similar to the platelet membrane GpIIb-IIIa complex have been described. The functional role of this complex in ECs remains to be established. In this study we show that the antigens recognized by polyclonal antibodies raised against human platelet GpIIb-IIIa and crossreacting with the EC form have a discrete and well-organized distribution at cell adhesion structures. Indeed these antigens are located at vinculin-rich focal contacts found at the membrane insertion of microfilament bundles of the stress fiber type. They are also found at cell-to-cell contacts and, with a diffuse pattern, at the dorsal surface of ECs. GpIIb-IIIa antibodies, added to EC suspensions prior to plating, inhibit EC spreading on fg and vitronectin (vn) substrata in a concentration-dependent way. In contrast, the antibodies are very poorly active when the cells are seeded on fn-coated glass. The same antibodies, added to adherent cells, disrupt cell-to-cell contacts and cause their rounding and detachment. Overall these results indicate that EC GpIIb-IIIa complex is involved in controlling the adhesion mechanism of these cells to extracellular matrix proteins.  相似文献   
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