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11.
Background Acute myocardial infarction (AMI) is a common cause of heart failure (HF), which can develop soon after AMI and may persist or resolve or develop late. HF after an MI is a major source of mortality. The cumulative incidence, prevalence and resolution of HF after MI in different age groups are poorly described. This study describes the natural history of HF after AMI according to age. Methods Patients with AMI during 1998 were identified from hospital records. HF was defined as treatment of symptoms and signs of HF with loop diuretics and was considered to have resolved if loop diuretic therapy could be stopped without recurrence of symptoms. Patients were cate- gorised into those aged 〈 65 years, 65-75 years, and 〉 75 years. Results Of 896 patients, 311,297 and 288 were aged 〈 65, 65-75 and 〉75 years and of whom 24%, 57% and 82% had died respectively by December 2005. Of these deaths, 24 (8%), 68 (23%) and 107 (37%) oc- curred during the index admission, many associated with acute HF. A further 37 (12%), 63 (21%) and 82 (29%) developed HF that persisted until discharge, of whom 15, 44 and 62 subsequently died. After discharge, 53 (24%), 55 (40%) and 37 (47%) patients developed I-IF for the first time, of whom 26%, 62% and 76% subsequently died. Death was preceded by the development of HF in 35 (70%), 93 (91%) and 107 (85%) in aged 〈 65 years, 65-75 years and 〉75 years, respectively. Conclusions The risk of developing HF and of dying after an MI in- creases progressively with age. Regardless of age, most deaths after a MI are preceded by the development of HF.  相似文献   
12.
Gaetani  GF; Kirkman  HN; Mangerini  R; Ferraris  AM 《Blood》1994,84(1):325-330
The catalase within normal, intact human erythrocytes was completely inactivated with amino triazole. The rate of 14CO2 evolution, when the cells were subsequently incubated with 14C-labeled glucose, provided a measure of the rate at which NADPH was being oxidized by the glutathione peroxidase/reductase system for the disposal of H2O2. This rate was determined in control cells and in catalase-inactivated cells while the cells were exposed to H2O2, which was generated at various constant and predetermined rates by glucose oxidase. The results indicated that catalase handles approximately half of the generated H2O2. The glutathione peroxidase/reductase mechanism accounted for the other half. These results are in agreement with our earlier findings on erythrocytes of a subject with a genetic deficiency of catalase. However, an unexpected result with the present approach was the finding that the increased dependence on the glutathione peroxidase/reductase mechanism did not occur until greater than 98% of the catalase had been inactivated. The latter observation indicates that catalase and the glutathione peroxidase/reductase system function intracellularly in a manner very different from that previously ascribed to them. An explanation of the findings requires that the two methods of H2O2 disposal function in a coordinated way, such as a sequential action in which the glutathione peroxidase/reductase system is the rate-limiting step.  相似文献   
13.
Ws/Ws rats have a small deletion at the tyrosine kinase domain of the c- kit gene and are deficient in both mucosal mast cells (MMC) and connective tissue-type mast cells (CTMC). The role of the c-kit receptor in the development of MMC and CTMC was investigated by infecting Ws/Ws and control +/+ rats with Nippostrongylus brasiliensis (NB), which induces T-cell-dependent mast cell proliferation. Although mast cells did not develop in the skin of Ws/Ws rats, a significant number of mast cells developed in the jejunum after NB infection. These mast cells had the MMC protease phenotype (rat mast cell protease [RMCP] I-/II+) and lacked heparin because they were not stained with berberine sulfate. Globule leukocytes were also detected in the mucosal epithelium of these rats. However, the number of MMC and the serum concentration of RMCP II in NB-infected Ws/Ws rats were only 13% and 7% of those of NB-infected +/+ rats, respectively. A small number of mast cells also developed in the lung, liver, and mesenteric lymph nodes of Ws/Ws rats after NB infection. Although mast cells in these tissues had the MMC phenotype throughout the observation period, the increased mast cells in the lung and liver of +/+ rats acquired a CTMC-like phenotype and were RMCP I+/II+, berberine sulfate+, and formalin resistant. These results indicate that the need for the stimulus through the c-kit receptor appears to be greater in the development of CTMC in the skin as well as for CTMC-like mast cells in the lung and liver than for the development of MMC.  相似文献   
14.
Introduction Allergic diseases are unfortunately on the increase. This is due to the massive exposure to chemicals and pollutants contained in the air we breathe, in the food we eat and in the water we drink. This is also due both to the stressful life we lead nowadays, which causes energetical unbalances in our immune system, and to the contact with unfamiliar allergens coming from foreign Countries.  相似文献   
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有机硒化合物对白三烯B4生物合成的影响   总被引:4,自引:0,他引:4  
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17.
Summary.  The genomic sequences of 3 strains of Lumpy skin disease virus (LSDV) (Neethling type) were compared to determine molecular differences, viz. the South African vaccine strain (LW), a virulent field-strain from a recent outbreak in South Africa (LD), and the virulent Kenyan 2490 strain (LK). A comparison between the virulent field isolates indicates that in 29 of the 156 putative genes, only 38 encoded amino acid differences were found, mostly in the variable terminal regions. When the attenuated vaccine strain (LW) was compared with field isolate LD, a total of 438 amino acid substitutions were observed. These were also mainly in the terminal regions, but with notably more frameshifts leading to truncated ORFs as well as deletions and insertions. These modified ORFs encode proteins involved in the regulation of host immune responses, gene expression, DNA repair, host-range specificity and proteins with unassigned functions. We suggest that these differences could lead to restricted immuno-evasive mechanisms and virulence factors present in attenuated LSDV strains. Further studies to determine the functions of the relevant encoded gene products will hopefully confirm this assumption. The molecular design of an improved LSDV vaccine is likely to be based on the strategic manipulation of such genes. Received November 25, 2002; accepted February 17, 2003 Published online May 5, 2003  相似文献   
18.
盐酸放线瑞香宁(actinodaphine-HCl)系从莲叶桐科青藤属植物黑吹风(Illigera khasiana C.B Clarke)中分离提取而得的有效成分,结构式如图1。药理试验证明有解热、镇痛、解痉等作用。本文报告用紫外二阶导数光谱法研究盐酸放线瑞香宁在兔体内的药代动力学结果。家兔4只,体重2.8±0.6kg。盐酸放线瑞香宁由本所植化室提供。氯仿、乙醇均为A.R。Perkin-Elmer型紫外—可见光分光光度计系美国产品。  相似文献   
19.

Background  

Early diagnosis of dementia benefits both patient and caregiver. Nevertheless, dementia in primary care is currently under-diagnosed. Some educational interventions developed to improve dementia diagnosis and management were successful in increasing the number of dementia diagnoses and in changing attitudes and knowledge of health care staff. However, none of these interventions focussed on collaboration between GPs and nurses in dementia care. We developed an EASYcare-based Dementia Training Program (DTP) aimed at stimulating collaboration in dementia primary care. We expect this program to increase the number of cognitive assessments and dementia diagnoses and to improve attitudes and knowledge of GPs and nurses.  相似文献   
20.
青蒿素(1)是从青蒿(Artemisia annua)中分离得到的一个抗疟化合物。青蒿素的发现改变了以往抗疟药物均为含氮杂环化合物的格式,开创了一类以过氧化合物为特征的、对抗氯喹虫株有效的新型抗疟药物。七十年代青蒿素结构发表以来,国内外在化学、药理以及临床方面均进行了大量工作,成为当今抗疟药方面最活跃的一个研究课题。这里简要报道  相似文献   
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