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Anomalies in prostaglandin (PG) synthesis have been suggested in both experimental and human diabetes mellitus; increased levels of plasma and tissue eicosanoids has been recently reported by several investigators. One step in prostaglandin synthesis is the enzymatic hydrolysis of membrane phospholipids by Phospholipase A2 (PLA2). Nevertheless the alternative pathway involving Phospholipase C must be considered. An evaluation of PLA2 activity is therefore a useful method for studying prostaglandin synthesis in the peripheral target tissues of insulin activity. We studied PLA2 activity in normal and diabetic rat muscle. Streptozotocin-induced diabetic rats showed significantly higher muscular PLA2 activity when compared with controls (3.04 x 10(-2) +/- 0.50 x 10(-2) versus 1.34 x 10(-2) +/- 0.35 x 10(-2) arachidonic acid pMol.mg protein-1.min-1 (p less than 0.01). This effect was not observed in diabetic animals successfully treated with insulin (1.78 x 10(-2) +/- 0.5 x 10(-2) versus 1.34 x 10(-2) +/- 0.35 x 10(-2) arachidonic acid pMol.mg protein-1.min-1), and a significant correlation was found between blood glucose and muscular PLA2 activity (r = 0.42; p less than 0.05). Our results clearly show that in streptozotocin-induced diabetic rats muscular PLA2 activity is significantly higher. The relationship between blood glucose levels and muscular PLA2 activity and the decrease of PLA2 activity after insulin treatment suggest that these changes may be related to a defect in insulin effect.  相似文献   
3.
A total of 79 dizziness patients were examined by either computed tomography (CT), or very low field magnetic resonance imaging (MRI), or both. In most cases, the patients were selected for the neuroimaging because preliminary clinical examination had suggested central nervous system (CNS) involvement. Abnormal CT or MRI findings with probable clinical relevance to the etiology of dizziness were obtained in 34%. The most common abnormalities were atrophy, infarction, and demyelination.; 29% of the CT scans and 40% of the MRI showed relevant abnormalities. The present results emphasize the diagnostic usefulness of head CT and MRI when dizziness of CNS etiology is suspected.  相似文献   
4.
Familial amyloidosis, Finnish type (FAF) (gelsolin-related amyloidosis) is an autosomal dominant form of systemic amyloidosis characterized by corneal lattice dystrophy and peripheral polyneuropathy. The accumulating protein in FAF consists of fragments of gelsolin, an actin-modulating protein. The gelsolin mutation G654A has been found in both Finnish and Japanese patients. To study the origin of the gelsolin mutation in these patients we performed haplotype analysis in 10 Finnish and 2 Japanese FAF families. Poymorphic DNA markers GSN, D9S103, AFMa061xd9, and AFMa139xb9 revealed a uniform disease haplotype in all the disease-associated chromosomes of the Finnish FAF families, which was different from the one observed in the Japanese families. The present results and the previously detected gelsolin mutation G654T in Czech and Danish FAF patients suggest that nucle otide 654 may represent a mutation hot spot in the gelsolin gene. The DNA markers studied here will be useful in future genealogical analyses of FAF. © 1995 Wiley-Liss, Inc.  相似文献   
5.
The use of apheretic procedures in pediatric patients has always been restricted by technical difficulties and the low incidence of diseases requiring this kind of treatment. The aim of the present study was to describe the solutions adopted to solve technical difficulties related to priming, vascular access and monitoring and then to evaluate clinical results. Between 1982 and 2000, 51 consecutive children (28 male, 23 female) with a mean age of 4.9 +/- 4.8 years (3 months-14.8 years) and a mean weight of 19.7 +/- 12.8 kg (5-52 kg), with renal and/or extra-renal diseases requiring apheretic procedures were selected for the study. The overall number of procedures performed were: 226 plasma-exchange (PE), 6 LDL-apheresis (LDL-A) and 8 protein A immunoadsorption (IAPA) sessions. Our therapeutic protocol involves hematic flux of 20-100 ml/min and ultrafiltration of 5-20 ml/min. In each 70-95 minute session we exchanged plasmatic volume with fresh frozen plasma or with a solution of 6% albumin in lactated Ringer's, using heparin (10-20 UI/kg/h). We used Paired Filtration Dialysis Monitor in PE and LDL-A; Citem 10 in IAPA. As plasma separator, we used a filter made of polypropylene, 0.2 m2 surface, 30 ml priming (Hemaplex BT 900). Hemolytic uremic syndrome was the most commonly treated disease (18/51 cases) with good results in 10/18 cases. We recorded, good results in vasculitis as well, in one girl with focal glomerulosclerosis in transplanted kidney and rapid improvement in all children with Guillaine-Barré Syndrome. PE treatment was effective in metabolic disorders such as tirosynemia and familiar hypercholesterolemia. Only 4/12 patients with acute liver failure due to viral hepatitis recovered. We had poor results in the remaining eight cases. Complications were rare and no viral infection was found in any patient. Our data show that it is possible to use these procedures in pediatric patients even though clinical indications and real effectiveness still need to be cleared up.  相似文献   
6.
OBJECTIVES: To assess, in women participating in a breast cancer prevention trialon fenretinide (4-HPR), the relationship of drug and retinol levels with the risk of second breast malignancy, taking into account age and menopausal status. METHODS: In a multicenter prevention trial, women with early breast cancer were randomly assigned to receive no treatment or 200 mg of 4-HPR/day for 5 years. Blood was collected at baseline and on a yearly basis during intervention from women recruited at the Istituto Tumori (Milan, Italy; 818 and 756 in the 4-HPR and control arm, respectively, who accounted for 53% of the participants in the trial). The plasma concentrations of 4-HPR, its main metabolite N-(4-methoxyphenyl) retinamide, and retinol were assayed by high-performance liquid chromatography. Three age ranges (or=56 years), menopausal status at baseline, and disease outcome at a median follow-up of 97 months were taken into account in the analysis. RESULTS: Baseline retinol levels were significantly lower (P or=46 years versus or= 0.71; P 相似文献   
7.
目的:比较评估腹腔镜与开腹结肠切除术对八旬老年结肠直肠癌患的早期疗效。方法:根据性别、年龄、手术时间、肿瘤位置以及入院并发症等条件,选取相匹配的分别接受腹腔镜结肠切除术(腹腔镜组)与开腹结肠切除术(开腹组)的结肠直肠癌患各61例,同时对其入院和出院时的状况进行评估。结果:腹腔镜组年龄82.3±3.5岁,开腹组年龄83.1±3.3岁,其术式转换率为6.1%。腹腔镜组的手术时间较开腹组多49min(P=0.001),两组手术总死亡率为2.4%。腹腔镜组与开腹组的术后发病率分别为21.5%和31.1%(P=0.30),其中腹腔镜组术后结肠功能恢复较快(P=0.01),平均住院时间明显缩短(9.8dvs12.9d;P=0.001),术后独立存活期较长(P=0.02)。结论:对八旬老年结肠直肠癌患施行腹腔镜结肠切除术安全有效,且患住院时间明显缩短,术后独立存活期明显延长。  相似文献   
8.
Currently there is an increasing trend of substance abuse in developing countries like India. This study attempted to identify the different predisposing factors, associated psycho-social and medical problems, prevalence and types of substance abuse in students. The study covered a cross-section of 720 students with an overall male to female ratio of 4.1:1. The majority of the sufferers were from middle socioeconomic class, aged between 15 and 19 years. Common substances of abuse were chewable tobacco and cannabis. The risk of abuse was more in hostellers hailing from broken families (62.5%). Friends had the highest influence (59%). Most of them (49.4%) tried multiple times to give up, but peer pressure (53%) compelled them to restart. In 60.8% cases the parents were completely unaware about this behavior. The commonly associated problems were psychological (34.3%) and medical (29.5%).Our study at the end points out major risk factors and their remedial measures to curb substance abuse.  相似文献   
9.
This review discusses common mental health disorders and their associations with cardiovascular disease risks. Commonly found mental health disorders include depression, anxiety, and personality types. The link between depression and cardiovascular disease mortality has been established. Depression is also common in patients with heart failure. In addition to discussing psychological disorders, a review of psychotropic drugs is also included. Drugs are described for therapy for depression and anxiety, as well as associations with cardiovascular drug-drug interactions. Drug-drug interactions are more common and potentially dangerous in elderly patients, in whom the conditions often coexist. The most common drug-drug interactions involve the P450 system of enzymes.  相似文献   
10.
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