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101.
Lyonne NL Zonneveld Adriaan van 't Spijker Jan Passchier Jan J van Busschbach Hugo J Duivenvoorden 《BMC public health》2009,9(1):251
Background
In primary care, up to 74% of physical symptoms is classified as unexplained. These symptoms can cause high levels of distress and healthcare utilization. Cognitive behavioral therapy has shown to be effective, but does not seem to be attractive to patients. An exception herein is a therapy based on the consequences model, which distinguishes itself by its labeling of psychosocial distress in terms of consequences rather than as causes of physical symptoms. In secondary care, 81% of the patients accepts this therapy, but in primary care the outcome is poor. We assume that positive outcome can also be reached in primary care, when the consequences model is modified and used bottom-up in an easily accessible group training, in which patients are relieved of being blamed for their symptoms. Our aim is to investigate the (cost-)effectiveness of this training. 相似文献102.
Letvin NL; Ritz J; Guida LJ; Yetz JM; Lambert JM; Reinherz EL; Schlossman SF 《Blood》1985,66(4):961-966
The effects of in vivo administration of three monoclonal antibodies specific for T11, the E rosette receptor on T lymphocytes, were examined in the rhesus monkey (Macaca mulatta). These three monoclonal antibodies were of different isotypes and were shown in in vitro studies to have differing affinities for the monkey T11 structure. Furthermore, each antibody induced antigenic modulation of T11 from the cell membrane of the lymphocytes to varying degrees in vitro. In vivo infusion of each of these antibodies into normal rhesus monkeys caused remarkably different effects on the circulating T lymphocyte pool. Infusion of these antibodies at doses of 2 mg/kg caused the coating of circulating T lymphocytes with antibody, the modulation of T11 off the T cell surface and the transient clearance of T cells from the circulation. Yet, the variation in the extent to which these effects were seen with these different antibodies indicates that extrapolating from studies of the in vivo use of one antibody to the use of another may be quite difficult. These studies clearly indicate the strengths of this nonhuman primate system for exploring the uses of monoclonal antilymphocyte antibodies as therapeutic agents. They, however, also demonstrate that differences may exist in the affinity of a particular antibody for homologous lymphocyte surface structures in humans and in a nonhuman primate species. These differences may make it difficult to predict the precise effects that the infusion of an antibody will cause in humans on the basis of alterations it induces in nonhuman primates. 相似文献
103.
104.
105.
Interaction of stem cell factor and its receptor c-kit mediates lodgment and acute expansion of hematopoietic cells in the murine spleen 总被引:7,自引:4,他引:7
The phenotypes of mice that harbor a defect in the genes encoding either stem cell factor (SCF) or its receptor, c-kit, indicate that this ligand/receptor pair is necessary for maintenance of normal hematopoiesis in the adult. Our objective was to determine whether SCF, like erythropoietin, is necessary for acute erythroid expansion during recovery from hemolytic anemia. Monoclonal antibody ACK2, which recognizes the murine c-kit receptor, was used to selectively block the hematopoietic growth-promoting effects of SCF. Mice were treated with phenylhydrazine on day 0 and day 1 to induce hemolytic anemia and also received no antibody, control IgG, or ACK2 on day 0. The mice were killed on day 3 and the hematocrit (Hct), reticulocyte count, and numbers of erythroid and myeloid hematopoietic progenitor cells (colony- forming unit-erythroid [CFU-E], burst-forming unit [BFU]-E, and CFU- granulocyte-macrophage [GM]) were quantitated in the femoral marrow and spleen using hematopoietic colony-forming assays. Induction of hemolytic anemia with phenylhydrazine resulted in a drop in the Hct from approximately 50% to 30%, and an approximate 8- to 10-fold increase in the reticulocyte count. The numbers of CFU-E increased modestly in the femur, and approximately 25- to 50-fold in the spleen, in comparison with normal mice. BFU-E and CFU-GM values did not increase in the femur but expanded 6- to 10-fold in the spleen, in comparison with normal mice. This confirms that much of the erythroid expansion in response to hemolytic anemia occurs in the murine spleen. Neutralizing quantities of the ACK2 antibody reduced femoral CFU-E, BFU- E, and CFU-GM content to less than half that found in phenylhydrazine- treated control mice and nearly totally ablated splenic hematopoiesis. These results suggest that c-kit receptor function may be required for optimal response to acute erythropoietic demand and that erythropoiesis in the splenic microenvironment is more dependent on SCF/c-kit receptor interaction than is erythropoiesis in the marrow microenvironment. Because expansion of late erythropoiesis in the spleen was preferentially blocked, we tested the hypothesis that homing of more primitive hematopoietic cells to the spleen was dependent on c-kit receptor function. Lethally irradiated mice were injected with marrow cells obtained from mice that had received phenylhydrazine plus control IgG or with marrow cells obtained from mice that had received phenylhydrazine plus ACK2. In parallel experiments, normal murine marrow cells were treated in vitro with control IgG or with ACK2 and were injected into lethally irradiated mice. The fraction of BFU-E and CFU-GM retrieved from the marrow and spleen of the recipient mice 4 hours later was reduced by approximately 75% when progenitor cells had been exposed to ACK2, in comparison with control IgG. These data suggest that interaction of SCF with the c-kit receptor affects the homing behavior of hematopoietic progenitor cells in the adult animal. 相似文献
106.
Tumor necrosis factor leads to the internalization and degradation of thrombomodulin from the surface of bovine aortic endothelial cells in culture 总被引:19,自引:2,他引:19
Tumor necrosis factor (TNF), a mediator of the inflammatory response, induces tissue factor and decreases the expression of thrombomodulin (TM) on endothelial cells, thus shifting the hemostatic properties of the endothelium. To determine the mechanism of TM downregulation, bovine aortic endothelial cells in culture were treated with TNF (2 nmol/L) and the fate of TM followed. Both surface expressed TM (antigen and activity), and the total TM pool (measured by radioimmunoassay and activity in detergent extracts) dropped to less than or equal to 20% of control values within 12 hours of TNF treatment. TM was not found in an immunologically recognizable form in the supernatants of treated cultures. Chloroquine (greater than or equal to 100 mumol/L) was able to abrogate the TNF effect on the total TM pool but not the effect on surface-expressed TM activity. We conclude that TNF induces the internalization and subsequent degradation of the TM molecule. None of the components of the protein C anticoagulant pathway, either alone or in combination, prevented the TNF-dependent downregulation of TM antigen. 相似文献
107.
Physiologic features of hemolysis axxociated with altered cation and 2,3-diphosphoglycerate content 总被引:1,自引:0,他引:1
A hemolytic disorder characterized by altered RBC cation composition (increases Na, decreases K), reduced monovalent cation content (decreased Na + K/liter RBC), and decreased levels of 2,3- diphosphoglycerate (2,3-DPG) is described. The etiology of these RBC abnormalities was not elucidated following extensive laboratory evaluation, although two important physiologic principles were manifested by this case: (1) Hemolysis was relatively well compensated (41% hematocrit) despite a significantly decreased RBC survival (51 Cr t 1/2 = 10.5 days). This effect presumably was due to reduced 2,3-DPG content (1.9 mumol/ml RBC) and the associated increase in whole blood oxygen affinity (P50 = 19.6 mm hg). (2) RBC size and water content were normal in spite of marked cation depletion. This anomaly was thought to reflect the osmotic effects of reduced polyvalent anion (2,3-DPG) content. 相似文献
108.
LS Moulton NL Green T Sudahar NK Makwana JP Whittaker 《Annals of the Royal College of Surgeons of England》2015,97(4):279-282
Introduction
In 2012, 2.6% of hip-fracture patients in the UK were treated conservatively. There is little data on outcome for these patients. However, one study demonstrated that though 30-day mortality is higher, mortality over the rest of the year is comparable with that in surgical groups. Therefore, we assessed conservatively managed patients in our unit.Methods
Patients with intracapsular fractures of the femoral neck treated by conservative means between 2010 and 2012 inclusive were identified. Data were collected: American Society of Anaesthesiologists (ASA) grade, Nottingham Hip Fracture Score (NHFS), mobility, mortality (30 days and one year) and pain levels.Results
Thirty-two patients formed the study cohort. Mean age was 85.6 years. Median ASA grade was 4. Mortality at 30 days and one year was 31.3% and 56.3%, respectively. There was one case of pneumonia and one of infection. Pressure sores or venous thromboembolism were not documented. Three patients underwent surgery once their health improved. In general, mobility was decreased, but 30.8% of patients could mobilise with two aids or a frame. Only two cases had ongoing problems with pain.Conclusions
Our data are similar to those published previously. Our patients were likely to have higher mortality data due to selection bias. Thirty-day mortality was significantly higher than the national average, but patients surviving 30 days had a prevalence of mortality similar to those managed by surgical means. Despite mobility decreasing from the pre-admission status, a considerable number of patients were free of pain and could mobilise. These data suggest that conservative management of intracapsular fractures of the femoral neck can produce acceptable results. 相似文献109.