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991.
We studied positivity for anti-cardiolipin antibody, intraglomerular capillary thrombi on renal biopsy, and the progression of renal disease in 51 patients (10 male and 41 female), mean age 37 years (range 17-65 years), with a diagnosis of systemic lupus erythematosis and clinically evident nephritis confirmed by renal biopsy. Serum creatinine, serum indicators of disease activity and biopsies were analysed in subgroups according to thrombi and anticardiolipin status. End-points were death or chronic dialysis requirement and survival. Degree of sclerosis, crescent formation and necrosed glomeruli were all greater in those specimens positive for thrombi and in those specimens of patients who were serum ACA-positive, suggesting a relationship to disease activity/severity at presentation. The increase in serum anti-DNA antibodies and ANA and the reduction in C3 and C4 were significant in ACA-positive patients, with a strong relationship to disease activity when compared with changes in the ACA-negative patients (p < 0.05 in all cases). There was no significant difference when patients were separated according to the presence or absence of thrombi. Renal function at presentation was worse in patients with intracapillary thrombi and ACA positivity (p = 0.085 and p = 0.042, respectively). All patients progressed, but only those with intracapillary thrombi or anti- cardiolipin antibody positivity had a significant deterioration in renal function. Twenty-one thrombotic episodes occurred in 14 patients, of whom 13 were ACA-positive. Anticardiolipin antibody is a strong predictor of the presence of intraglomerular thrombi in SLE patients with renal involvement. The presence of thrombi and/or anticardiolipin antibodies indicate a worse long-term renal outcome. Anti-cardiolipin antibody positivity is a strong predictor of systemic vascular thrombotic complications.   相似文献   
992.
Ries AL 《Respiratory care》2008,53(9):1203-1207
Pulmonary rehabilitation has emerged as a standard of care for patients with chronic lung disease, based on a growing body of scientific evidence. Over recent decades, several organizations have championed pulmonary rehabilitation and developed comprehensive statements, practice guidelines, and evidence-based guidelines. Documenting the scientific evidence underlying clinical practice has been important in overcoming skepticism and convincing health professionals, health-care institutions, third-party payers, and regulatory agencies to support pulmonary rehabilitation programs. The literature on pulmonary rehabilitation has increased substantially and provided justification for including pulmonary rehabilitation in practice guidelines for chronic obstructive pulmonary disease and other chronic lung diseases. Therefore, the American College of Chest Physicians and the American Association of Cardiovascular and Pulmonary Rehabilitation decided to update their 1997 guidelines with a systematic, evidence-based review of the literature since the previous review. The panel updated prior topics and recommendations and reviewed new topics. Recommendations were given for outcomes of comprehensive pulmonary rehabilitation programs, including lower-extremity exercise training, dyspnea, health-related quality of life, health-care utilization, survival, psychosocial outcomes, and long-term benefits. Additional topics include the duration of pulmonary rehabilitation, post-rehabilitation maintenance strategies, intensity of aerobic exercise training, strength training, anabolic drugs, upper-extremity training, inspiratory-muscle training, education, psychological and behavioral components, oxygen supplementation, noninvasive ventilation, nutrition supplementation, rehabilitation for patients with disorders other than chronic obstructive pulmonary disease, and future pulmonary rehabilitation research. These guidelines provide an excellent summary of the recent literature and further strengthen the scientific basis of pulmonary rehabilitation.  相似文献   
993.
BACKGROUND: Posttransfusion complications can be prevented by pretransfusion removal of donor white cells from platelet concentrate. The filtration used for this removal seems to have little effect on platelet function and activation, but more information is needed on its effect on function during subsequent long-term storage of concentrate. STUDY DESIGN AND METHODS: The effect of prestorage filtration of buffy coat-prepared platelet concentrates (PCs) on platelet function, metabolism, and activation was investigated. A pool of three PCs, each made of four buffy coats, was split into three equal volumes; two were filtered over two different filters and the third served as a control. Variables monitored immediately after filtration and during the subsequent 8-day storage period at 22 degrees C included aggregation upon stimulation with collagen and/or ADP, platelet adhesion capacity to collagen and fibrinogen in flowing blood, nucleotide content of and nucleobase release by the platelets, expression of activation-dependent antigens, and beta-thromboglobulin release by the platelets. RESULTS: No differences were observed between the PCs filtered over two different filters and the nonfiltered control PCs immediately after filtration and during storage, except for a selective removal (20%) of beta-thromboglobulin by one filter. CONCLUSION: PCs prepared from a pool of four buffy coats can be filtered and subsequently stored for 8 days (starting +/− 24 hours after whole blood collection) without detriment to platelet function, metabolism, or activation.  相似文献   
994.
995.
Desmopressin, (DDAVP; 1-desamino-8-D-arginine vasopressin) increases the release and activity of von Willebrand factor (vWF); however, its effects on the other major constituent of endothelial Weibel-Palade bodies, P-selectin, has not been investigated. DDAVP-induced P-selectin expression may explain DDAVP's efficacy in bleeding disorders in which vWF levels are normal. Therefore, the objective of this study is to assess the effect of DDAVP on P-selectin expression on endothelial cells of postcapillary venules in vivo and on human umbilical vein endothelium in vitro, and to determine whether DDAVP has direct effects on leukocyte behavior in postcapillary venules. DDAVP (0.1 and 1.0 microgram/mL) induced a significant but transient increase in P- selectin expression on human umbilical vein endothelial cells as well as on rat and human platelets. Immunohistochemical analysis of rat postcapillary venules showed that in contrast to saline, DDAVP injection (1 microgram/kg, intravenous) induced significant endothelial P-selectin expression. DDAVP administration also induced a rapid and significant increase in leukocyte rolling in rat mesenteric venules in vivo. This response was entirely dependent on P-selectin, as an anti-P- selectin antibody rapidly reversed the DDAVP-induced increase in leukocyte rolling. DDAVP induced leukocyte rolling in medium (20 to 40 microns) and large (> 40 microns), but not small (< 20 microns), postcapillary venules. In animals that were treated with DDAVP, there was a steady and significant increase in leukocyte adhesion. This study shows that DDAVP can directly induce P-selectin expression on endothelium in vitro and in vivo and that the latter response is capable of supporting prolonged leukocyte rolling in rat postcapillary venules.  相似文献   
996.
Patients with emphysema may experience reduced health-related quality of life (HRQOL). HRQOL measures have evolved from two different measurement traditions: psychometric theory and decision theory. Psychometric methods typically create a profile of outcomes, whereas decision theory methods offer a summary score on a continuum ranging from 0.0 (for death or worst possible health) to 1.0 (for best possible health). Decision theory methods are better suited for cost-effectiveness studies. Generic HRQOL measures can be applied to any disease population, whereas disease-targeted measures are tailored to a specific clinical condition. Disease-targeted measures are typically more sensitive to clinical change, but cannot offer a comparison basis for different clinical conditions. This article reviews the measurement of HRQOL in patients with emphysema. The National Emphysema Treatment Trial (NETT) offers an example of the application of both generic and disease-targeted, as well as profile and decision theory, methods. The NETT illustrates how HRQOL measures can be used to assess outcomes and estimate cost-effectiveness in a major clinical trial.  相似文献   
997.
AIM:To analyze the change of dimethylarginine plasma levels in cirrhotic patients receiving transjugular intrahepatic portosystemic shunt(TIPS).METHODS:To determine arginine,asymmetric dimethylarginine(ADMA),symmetric dimethylarginine(SDMA),and nitric oxide(NO) plasma levels,blood samples were collected from the superior cava,hepatic,and portal vein just before,directly after,and 3 mo after TIPS-placement.RESULTS:A significant increase in the arginine/ADMA ratio after TIPS placement was shown.Moreover,TIPS placement enhanced renal function and thereby decreased systemic SDMA levels.In patients with renal dysfunction before TIPS placement,both the arginine/ADMA ratio and creatinine clearance rate increased significantly,while this was not the case in patients with normal renal function before TIPS placement.Hepatic function did not change significantly after TIPS placement and no significant decline in ADMA plasma levels was measured.CONCLUSION:The increase of the arginine/ADMA ratio after TIPS placement suggests an increase in intracellular NO bioavailability.In addition,this study suggests that TIPS placement does not alter dimethylarginine dimethylaminohydrolase(DDAH) activity and confirms the major role of the liver as an ADMA clearing organ.  相似文献   
998.
Lucas  MG; Green  AM; Telen  MJ 《Blood》1989,73(2):596-600
The In(Lu) gene has been shown previously to downregulate expression by erythrocytes and by a subset of leukocytes of an 80-Kd protein antigen defined by monoclonal antibody (MoAb) A3D8. A3D8 antibody has also been shown by inhibition studies to recognize a serum antigen; this serum antigen is present in reduced amount in serum from In(Lu) donors. The present study demonstrates that the serum antigen recognized by A3D8 antibody also resides on a protein similar in size to the protein present in erythrocyte membranes. Studies using chromatographically purified protein have further shown that this antigen shares many epitopes with that present in RBCs and is therefore likely to be extremely homologous or identical to the erythrocyte In(Lu)-related p80.  相似文献   
999.
Saltman  DL; Ross  JA; Banks  RE; Ross  FM; Ford  AM; Mackie  MJ 《Blood》1989,74(6):2062-2065
To establish the clonal origin of a case of concomitant B-cell chronic lymphocytic leukemia (IgM kappa) and multiple myeloma (IGA lambda), we analyzed the immunoglobulin (Ig) gene rearrangements in the patient's blood and bone marrow. Despite the different isotypes, pretreatment investigation of the heavy chain gene (JH) revealed a germline fragment and two identical rearrangements in the blood and marrow. Both kappa and lambda light-chain genes were rearranged in the blood, suggesting peripheral blood lymphocyte involvement in the myeloma. Analysis of the Ig genes after chemotherapy demonstrated no change in the JH or CK rearrangements; however, the lambda genes were now in a germline configuration. Our results suggest that in this patient both chronic lymphocytic leukemia and myeloma originated from the same B-cell progenitor.  相似文献   
1000.
ABSTRACT: INTRODUCTION: The increasing number of reports on the relation between transfusion of stored red blood cells (RBCs) and adverse patient outcome has sparked an intense debate on the benefits and risks of blood transfusions. Meanwhile, the pathophysiological mechanisms underlying this postulated relation remain unclear. The development of hemolysis during storage might contribute to this mechanism by release of free hemoglobin (fHb), a potent nitric oxide (NO) scavenger, which may impair vasodilation and microcirculatory perfusion after transfusion. The objective of this prospective observational pilot study was to establish whether RBC transfusion results in increased circulating fHb levels and plasma NO consumption. In addition, the relation between increased fHb values and circulating haptoglobin, its natural scavenger, was studied. METHODS: Thirty patients electively received 1 stored packed RBC unit (n = 8) or 2 stored packed RBC units (n = 22). Blood samples were drawn to analyze plasma levels of fHb, haptoglobin, and NO consumption prior to transfusion, and 15, 30, 60 and 120 minutes and 24 hours after transfusion. Differences were compared using Pearson's chi-square test or Fisher's exact test for dichotomous variables, or an independent-sample t test or Mann-Whitney U test for continuous data. Continuous, multiple-timepoint data were analyzed using repeated one-way analysis of variance or the Kruskall-Wallis test. Correlations were analyzed using Spearman or Pearson correlation. RESULTS: Storage duration correlated significantly with fHb concentrations and NO consumption within the storage medium (r = 0.51, P < 0.001 and r = 0.62, P = 0.002). fHb also significantly correlated with NO consumption directly (r = 0.61, P = 0.002). Transfusion of 2 RBC units significantly increased circulating fHb and NO consumption in the recipient (P < 0.001 and P < 0.05, respectively), in contrast to transfusion of 1 stored RBC unit. Storage duration of the blood products did not correlate with changes in fHb and NO consumption in the recipient. In contrast, pre-transfusion recipient plasma haptoglobin levels inversely influenced post-transfusion fHb concentrations. CONCLUSION: These data suggest that RBC transfusion can significantly increase post-transfusion plasma fHb levels and plasma NO consumption in the recipient. This finding may contribute to the potential pathophysiological mechanism underlying the much-discussed adverse relation between blood transfusions and patient outcome. This observation may be of particular importance for patients with substantial transfusion requirements.  相似文献   
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