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排序方式: 共有344条查询结果,搜索用时 18 毫秒
11.
Immunologic status of hemophilia patients treated with cryoprecipitate or lyophilized concentrate 总被引:1,自引:0,他引:1
We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A. 相似文献
12.
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
13.
Helen Pineo Ketevan Glonti Harry Rutter Nici Zimmermann Paul Wilkinson Michael Davies 《Journal of urban health》2018,95(5):613-646
Urban health indicator (UHI) tools provide evidence about the health impacts of the physical urban environment which can be used in built environment policy and decision-making. Where UHI tools provide data at the neighborhood (and lower) scale they can provide valuable information about health inequalities and environmental deprivation. This review performs a census of UHI tools and explores their nature and characteristics (including how they represent, simplify or address complex systems) to increase understanding of their potential use by municipal built environment policy and decision-makers. We searched seven bibliographic databases, four key journals and six practitioner websites and conducted Google searches between January 27, 2016 and February 24, 2016 for UHI tools. We extracted data from primary studies and online indicator systems. We included 198 documents which identified 145 UHI tools comprising 8006 indicators, from which we developed a taxonomy. Our taxonomy classifies the significant diversity of UHI tools with respect to topic, spatial scale, format, scope and purpose. The proportions of UHI tools which measure data at the neighborhood and lower scale, and present data via interactive maps, have both increased over time. This is particularly relevant to built environment policy and decision-makers, reflects growing analytical capability and offers the potential for improved understanding of the complexity of influences on urban health (an aspect noted as a particular challenge by some indicator producers). The relation between urban health indicators and health impacts attributable to modifiable environmental characteristics is often indirect. Furthermore, the use of UHI tools in policy and decision-making appears to be limited, thus raising questions about the continued development of such tools by multiple organisations duplicating scarce resources. Further research is needed to understand the requirements of built environment policy and decision-makers, public health professionals and local communities regarding the form and presentation of indicators which support their varied objectives. 相似文献
14.
Importance of catalase in the disposal of hydrogen peroxide within human erythrocytes 总被引:2,自引:1,他引:2
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
15.
Von Willebrand's Syndrome Presenting as an Acquired Bleeding Disorder in Association With a Monoclonal Gammopathy 总被引:1,自引:0,他引:1
The clinical and laboratory findings of apatient with a bleeding disorder, laboratoryfeatures of von Willebrand's disease, and amonoclonal gammopathy are described.There was no evidence of von Willebrand'sdisease in his five children. Laboratory features of von Willebrand's disease in thepatient included a long bleeding time, lowfactor VIII level by one- and two-stageclotting assays and by immunoassay, decreased platelet glass adhesiveness usingnative and heparinized blood, and correction of platelet adhesiveness by additionof cryoprecipitate in vitro. Attempts to implicate the monoclonal IgG in the pathogenesis of the von Willebrand's syndromewere unsuccessful using the followingtests: immunoprecipitation with normalplasma, antibody activity identified bypassive cutaneous anaphylaxis, inhibitionof biological factor VIII activity, and binding to factor VIII. Despite these negativefindings, it is suggested that the clinicalpattern of this and previously describedcases of "acquired" von Willebrand's disease has an immunologic basis that maybe mediated by either humoral or cellularmechanisms. Submitted on September 26, 1972 Revised on February 8, 1973 Accepted on February 9, 1973 相似文献
16.
Arizono N; Kasugai T; Yamada M; Okada M; Morimoto M; Tei H; Newlands GF; Miller HR; Kitamura Y 《Blood》1993,81(10):2572-2578
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
17.
Summary There is now ample evidence to indicate that certain low-molecular-weight heparins given subcutaneously can replace continuous intravenous unfractionated heparin for the initial treatment of venous thromboembolism. The low-molecular-weight heparins have a predictably high absorption rate when given subcutaneously and a prolonged duration of action, permitting them to be given by a once or twice daily injection for the prevention or treatment of venous thrombosis. Furthermore, treatment does not require laboratory monitoring, thus eliminating the need for continuous IV infusion and permitting the early discharge of patients with venous thromboembolism. This should eventually lead to the outpatient treatment of venous thromboembolism. Studies to date indicate that low-molecular-weight heparin is more cost-effective than unfractionated heparin in the treatment of venous thromboembolism and the cost effectiveness will be increased by out-of-hospital treatment. At the present time, the findings associated with any individual lowmolecular-weight heparin preparation cannot be extrapolated to different low-molecular-weight heparins, and therefore each must be evaluated in separate clinical trials. The information to date is that low-molecular-weight heparin is safer and more effective than continuous intravenous unfractionated heparin in the treatment of proximal venous thrombosis. The decreased mortality rate seen in two clinical trials, particularly in patients with metastatic cancer, was quite unexpected. This requires further confirmation in larger prospective randomized trials. 相似文献
19.
Dalteparin sodium (Fragmin, Pharmacia Corporation) is a low molecular weight heparin (LMWH) with a mean molecular weight of approximately 5000 Da. As with the other LMWHs, dalteparin sodium has certain advantages over unfractionated heparin (UFH), most important of which are improved bio-availability by sc. injection, a prolonged antithrombotic activity which is highly correlated with body weight permitting the o.d. administration of the drug. Dalteparin sodium has been subjected to a large number of well-designed randomised clinical trials for the prevention and treatment of thrombotic disorders. Based on data from the randomised clinical trials, dalteparin sodium has been approved internationally for a wide spectrum of clinical indications (e.g., prevention of thromboembolic events after surgery). Dalteparin sodium has also been studied in randomised controlled trials in the maintenance of graft patentcy following peripheral vascular surgery, in place of warfarin for the long-term treatment of patients presenting with deep vein thrombosis (DVT), in the prevention of upper extremity thrombosis in patients with indwelling portacath devices and in pregnant patients with a history of previous venous thromboembolism with or without thrombophilia. Dalteparin sodium has been compared with heparin for the prevention of thrombotic complications during haemodyalisis and haemofiltration. These studies have shown promising results but further work is required before dalteparin sodium can be recommended for these indications. 相似文献
20.