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This study evaluates the effect of blood volume and hematocrit changes on brain tissue during temporary global ischemia. Normal saline was administered intravenously to 55 gerbils to achieve hypo-, normo-, and hypervolemic hemodilution and uniform 30% hematocrit reduction. Each group had unilateral carotid artery ligation and temporary (20 minute) contralateral carotid occlusion. After ten days or death, brains were harvested, preserved in formalin, sectioned in a manner which provided adequate samples of both cortex and hippocampus, and stained with H&E and luxol fast blue. They were then examined and staged microscopically for white and gray matter infarction, edema, and neuronal injury and loss. Histologic studies were performed in a randomized and blinded manner and were classified by one of four categories: normal, minimal, moderate, and severe changes. Three of ten (30%) controls survived ten days but had severe neuronal loss, minimal cerebral edema and a minimal to moderate number of white matter strokes. Survival was best in animals treated with hypovolemic hemodilution (43%). Other rates were: normovolemic (33%), controls (30%), and hypervolemic (8.3%). The degree of brain tissue damage was markedly less in the normovolemic group. In this model, normovolemic hemodilution followed by hypovolemic hemodilution offered the best overall cerebral protection during global ischemia.  相似文献   
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Fish oil has been recently proposed as a possible effective treatment in inflammatory bowel disease (IBD); however, a lot of annoying side effects (ie, belching, halitosis, diarrhea, etc) affect patient compliance. We carried out a study of patient tolerance in a group of Crohn's disease (CD) patients with a new fish oil derivative consisting of 500-mg capsules of eicosapentaenoic-docosahexaenoic (EPA 40%-DHA 20%), a free fatty acid mixture (Purepa), and we also evaluated its incorporation into phospholipids, both in plasma and in red cell membranes. Five groups of 10 CD patients in remission received nine Purepa capsules daily in four different preparations (A: uncoated, B: coated, pH 5.5; C: coated, pH 5.5, 60 min time release; D: coated, pH 6.9) and 12 × 1-g capsules daily of a triglyceride preparation (Max-EPA, EPA 18%-DHA 10%), respectively. We coated three of the four Purepa preparations in order to delay the release of contents in an attempt to minimize the side effects. After six weeks of treatment, the group taking Purepa capsules, coated, pH 5.5, 60 min time release (group C) showed the best incorporation of EPA and DHA in red blood cell phospholipid membranes (EPA from 0.2 to 4.4%, DHA from 3.7 to 6.3%), and no side effects were registered, whereas in all other groups side effects were experienced in 50% or more of subjects. This new preparation will make it possible to treat patients for long periods.  相似文献   
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The 8th Conference of the British Psychosocial Oncology Group was held in London on 9–10 December 1991 and attracted over 120 participants. The conference was extended from its usual one day format to one and a half days, to allow more time for both a formal and informal exchange of ideas. Eight invited speakers participated, but proferred papers and posters remained an important focus of the meeting. This is the largest annual conference in Britain for professionals working in psychosocial oncology and an important forum for the presentation of research. As in previous years, the conference attracted a number of newcomers, indicating the continued expansion of this field of research. A number of topical issues were presented in keynote papers by invited speakers. New work in cancer prevention and the associated areas of counselling families at risk and ethical issues, formed one symposium. Communication skills and relevant training needs in paediatric and adult oncology were an important theme of the conference and intervention studies formed the third main topic.  相似文献   
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Published reports regarding the stability of morphine are at variance, especially in syringes used in patient-controlled analgesia (PCA) devices. In addition to the effects of container type and vehicle, reasons for this variation include the effect of excipients temperature and light during storage. Furthermore, the literature varies regarding the mechanisms of decomposition for morphine. To our knowledge, the stability of meperidine (pethidine) stored in plastic syringes has not been reported. The purposes of this study were to investigate the stability of morphine sulphate (1 and 5 mg/ml) and meperidine hydrochloride (5 and 10 mg/ml) in plastic syringes for use in PCA devices for a duration of 12 weeks, and evaluate the influence of light (240 foot-candies), temperature (-20, 4 and 23d?C), diluent (5% dextrose or normal saline), and drug concentration on the stability of these narcotic analgesics. Samples were taken bi-weekly for solutions protected from light and weekly for solutions exposed to light. Morphine sulphate and meperidine hydrochloride concentrations were quantified using independent, stability-indicating, high performance liquid chromatographic assays. The within-day and between-day coefficients of variation for these assays were 4% over each of the concentration ranges studied. Under the conditions of this study, it is proposed that although decomposition of morphine to its main product, pseudomorphine, can be interpreted using first-order kinetics, consecutive (to form the N-oxide) and parallel mechanisms (to form apomorphine) exist. Morphine solutions were more stable in normal saline than in 5% dextrose. SheIf-life data indicate that morphine is stable for at least 6 weeks when protected from light. Exposure to light accelerates morphine decomposition two to six-fold depending on the concentration, and the shelf-life is reduced to about 1 week in some instances. Meperidine solutions in both vehicles under all conditions had shelf-lives of at least 12 weeks. No effects of light were detected and no changes in solution colour were observed. This study illustrates that patients using PCA devices must be advised about shelf-lives as well as correct storage conditions to protect solutions of these drugs from environmental factors that may alter shelf-lives. Pharmacists should also note that other formulation factors such as: antioxidants, preservations, buffers, impurities, and the source and quality of containers, may significantly alter the shelf-lives of these drugs.  相似文献   
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AIM: To investigate women's perceptions of the contribution of cardiac rehabilitation to their recovery from a myocardial infarction. BACKGROUND AND PURPOSE: Cardiac rehabilitation programs have been based on research with almost exclusively male participants. It was unclear if cardiac rehabilitation programs meet the needs of women. METHOD: Ten women who had experienced one or more myocardial infarctions were interviewed. Data from these interviews were analysed using Glaserian grounded theory. FINDINGS: The core category that emerged from the data was 'regaining everydayness'. Participants worked to regain their 'everydayness' through a basic social process of 'reframing'. Reframing involved coming to terms with what they had experienced and fitting it into their lives. Other categories related to symptom recognition and recovery. CONCLUSION: Cardiac rehabilitation programs contributed to overall recovery from a myocardial infarction in different ways for each participant. Although programs provided information for participants, they failed to provide the type of support needed to effectively aid reframing and recovery. Programs did not meet the needs of all participants and it was apparent that one size does not fit all.  相似文献   
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Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies.  相似文献   
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