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81.
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83.

Background  

Potassium disorders can cause major complications and must be avoided in critically ill patients. Regulation of potassium in the intensive care unit (ICU) requires potassium administration with frequent blood potassium measurements and subsequent adjustments of the amount of potassium administrated. The use of a potassium replacement protocol can improve potassium regulation. For safety and efficiency, computerized protocols appear to be superior over paper protocols. The aim of this study was to evaluate if a computerized potassium regulation protocol in the ICU improved potassium regulation.  相似文献   
84.

Background  

Pneumocystis jiroveci pneumonia (PCP) is an important opportunistic infection among immunosuppressed patients, especially in those infected with human immunodeficiency virus (HIV). The clinical presentation of PCP in immunosuppressed patients have been well-reported in the literature. However, the clinical importance of PCP manifesting in the setting of an immunorestitution disease (IRD), defined as an acute symptomatic or paradoxical deterioration of a (presumably) preexisting infection, which is temporally related to the recovery of the immune system and is due to immunopathological damage associated with the reversal of immunosuppressive processes, has received relatively little attention until recently.  相似文献   
85.
OBJECTIVES: The objective of this study was to test whether the auscultatory method and Finapres provide similar readings for blood pressure response during two resistance exercise protocols of different intensities, and to gain some insight into whether auscultation can be used to monitor cardiovascular stress during resistance exercise. METHODS: Fourteen patients performed six and 15 maximum repetitions (six and 15, respectively) of one-leg knee extension on different days. Blood pressure (BP) was measured simultaneously with the two methods at rest and during the last repetition of the protocols. RESULTS: Neither the systolic blood pressure (SBP) nor the diastolic blood pressure (DBP) differed between methods, both at rest and at six maximum repetitions. Conversely, Finapres recorded higher systolic blood pressure at 15 maximum repetitions (168.8+/-21.7 mmHg) than auscultation (147.0+/-14.5 mmHg; P<0.001). In addition, the blood pressure values obtained by both methods in each exercise protocol (six and 15 maximum repetitions, respectively) were ranked in tertiles and also treated by the gamma (gamma) nonparametric correlation. We observed a high probability for patients to be ranked on the same tertile regardless of the method used, at both six maximum repetitions (SBP=0.80, DBP=0.97) and 15 maximum repetitions (SBP=0.88, DBP=0.92). High association between methods was also observed by simple regression when measurements taken at rest and at each intensity were analyzed altogether for both SBP (r=0.95, r adjusted=0.89) and DBP (r=0.79, r adjusted=0.62). CONCLUSION: Auscultation provides lower BP values than Finapres, especially at the end of a set including 15 maximum repetitions. The former, however, seems appropriate to assess the relative cardiovascular stress imposed by different protocols of resistance exercise.  相似文献   
86.
Effect of freezing on the in vivo recovery of irradiated red cells   总被引:2,自引:0,他引:2  
BACKGROUND: Transfusion-associated graft-versus-host disease can be prevented by gamma radiation of blood components. The increased use of blood components donated for patients by their family members has resulted in an increased demand for the storage and handling of irradiated units, and the ability to freeze the cells would allow storage beyond their current expiration date. STUDY DESIGN AND METHODS: To assess the effect of freezing and deglycerolization on irradiated red cells, studies of autologous radiolabeled red cell recovery were performed using normal volunteers. Each unit of CPDA-1 red cells was immediately divided into two equal volumes. Further handling of each half was identical except that one was irradiated (3500 cGy). The units were grouped under three protocols: I, irradiated on Day 0 and frozen on Day 5 (n = 4); II, irradiated on Day 7, rejuvenated, and frozen on Day 14 (n = 5); and III, irradiated on Day 14, rejuvenated, and frozen on Day 18 (n = 3). All cells were frozen for 3 to 10 months at -80 degrees C. RESULTS: Irradiated and control units showed no significant differences in supernatant potassium or hemoglobin. Autologous 24-hour posttransfusion recoveries (mean +/− SD) for the three groups were: I, 89.7 +/− 5.6 percent (control, 90.6 +/− 3.2%); II, 85.3 +/− 5.7 percent (control, 83.7 +/− 3.0%); and III, 79.5 +/− 1.4 percent (control, 82.6 +/− 5.2%). CONCLUSION: Irradiated red cells can be frozen after being stored under various conditions and can still meet established guidelines requiring 75-percent recovery 24 hours after transfusion.  相似文献   
87.
ABSTRACT

Satellite-derived sea surface temperature (SST) presents discrepancies in both magnitude and temporal variability in the wind-driven coastal upwelling region off the Cape Frio (23°S) in Southeastern Brazil. Level 2 (L2) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and Aqua, and Level 4 (L4) SST products are compared with in situ measurements. Strong positive biases up to 4°C are systematically observed in L4 products during upwelling events and decrease to less than 1°C in non-upwelling days. Lower biases were found in L2 MODIS SST, and the statistical performance of L4 SST products did not present significant improvements in days when high-resolution clear-sky observations from MODIS were available. This indicates that spatio-temporal interpolation and ingestion of microwave-based data sets in L4 SST analyses are likely the main cause of observed discrepancies during upwelling events. Improved L2 SST retrieval algorithms and L4 SST analyses that take into account upwelling-related regional characteristics are required for more accurate satellite SST products over coastal regions.  相似文献   
88.
OBJECTIVE: Erythropoietin interacts with vascular endothelial growth factor (VEGF) and stimulates endothelial cell mitosis and motility; thus it may be of importance in the complex phenomenon of wound healing. The purpose of this study was to investigate the effect of recombinant human erythropoietin (rHuEPO) on experimental burn wounds. DESIGN: Randomized experiment. SETTING: Research laboratory. SUBJECTS: C57BL/6 male mice weighing 25-30 g. INTERVENTIONS: Mice were immersed in 80 degrees C water for 10 secs to achieve a deep-dermal second degree burn. Animals were randomized to receive either rHuEPO (400 units/kg/day for 14 days in 100 microL subcutaneously) or its vehicle alone (100 microl/day distilled water for 14 days subcutaneously). On day 14 the animals were killed. Burn areas were used for histologic examination, evaluation of neoangiogenesis by immunohistochemistry, and expression (Western blot) of the specific endothelial marker CD31 as well as quantification of microvessel density, measurement of VEGF wound content (enzyme-linked immunosorbent assay), expression (Western blot) of endothelial and inducible nitric oxide synthases, and determination of wound nitric oxide (NO) products. MEASUREMENTS AND MAIN RESULTS: rHuEPO increased burn wound reepithelialization and reduced the time to final wound closure. These effects were completely abated by a passive immunization with specific antibodies against erythropoietin. rHuEPO improved healing of burn wound through increased epithelial proliferation, maturation of the extracellular matrix, and angiogenesis. The hematopoietic factor augmented neoangiogenesis as suggested by the marked increase in microvessel density and by the robust expression of the specific endothelial marker CD31. Furthermore, rHuEPO enhanced the wound content of VEGF caused a marked expression of endothelial and inducible nitric oxide synthases and increased wound content of nitric oxide products. CONCLUSIONS: Our study suggests that rHuEPO may be an effective therapeutic approach to improve clinical outcomes after thermal injury.  相似文献   
89.
Purified CD34+ Lin- Thy+ stem cells do not contain clonal myeloma cells   总被引:6,自引:0,他引:6  
High-dose therapy with autologous marrow or peripheral blood stem cell (PBSC) rescue has been extensively applied in the treatment of multiple myeloma (MM) patients during the past 10 years resulting in improved event-free and overall survival when compared with standard chemotherapy. However, relapses are common and cure is unlikely in the majority of patients. Because both bone marrow and PBSCs are contaminated with myeloma cells it is conceivable that relapse after autotransplantation originates at least in part from autografted tumor cells. In this study, mobilized PBSCs were examined for the presence of myeloma cells based on immunophenotyping and sensitive polymerase chain reaction (PCR)-based techniques. In addition, CD34+ Lin- Thy+ stem cells were purified from mobilized PBSC harvests of 10 MM patients by sequentially using counterflow elutriation centrifugation, treatment with phenylalanine methylester, and flow sorting, using 5-parameter gating (propidium iodide, forward scatter, side scatter, CD34+ v Lin- and CD34+ v Thy+). Virtually all mobilized unsorted PBSC preparations contained myeloma cells in sufficient quantities (range, < 0.01 to > 10%) potentially causing a disease relapse. Stem cell purification led to an overall enrichment by about 50-fold in all 10 patients; approximately 90% of the final cell population expressed CD34+ Lin- Thy+ with no evidence of myeloma cell contamination based on flow cytometric analysis of CD38bright cells (< 0.1%). Quantitative PCR amplification of patient-specific complementarity determining region III (CDRIII) DNA sequences showed depletion of clonal B cells by 2.7 to 7.3 logs, with the highest log reduction noted in the samples initially containing the most tumor cells. Our results show that purification of CD34+ Lin- Thy+ cells depletes myeloma cells to undetectable levels from up to 10% present in unsorted PBSCs, thus offering a tool to investigate whether MM relapse after autotransplantation can be reduced markedly.  相似文献   
90.
OBJECTIVE: The aim of this study was to test the effect of gut manipulation by either novel synbiotics or by metronidazole on either endotoxemia or the severity of liver damage in the course of acute pancreatitis from alcohol ingestion. METHODS: Sprague–Dawley rats were fed for 1 week through an intragastric tube a liquid diet with either: (i) 1 mL t.i.d. of a mixture of synbiotics (Lactobacillus acidophilus, Lactobacillus helveticus and Bifidobacterium in an enriched medium); (ii) 20 mg/kg t.i.d. metronidazole; or (iii) standard diet. Then, acute pancreatitis was induced by caerulein and when the disease was full‐blown, rats were fed an alcohol‐rich diet. Synbiotic and metronidazole treatment was given for a further 2 weeks. Transaminase and endotoxemia levels were measured before treatment, after 6 h, after 24 h and 2 weeks later, at the time the rats were killed. Liver samples were obtained for histological analysis. RESULTS: Synbiotics but not metronidazole improved the acute pancreatitis‐induced increase in endotoxemia and transaminase levels. The addition of alcohol worsened these variables to a limited extent in the synbiotic‐treated group, while metronidazole had a negative effect on liver damage. CONCLUSIONS: Gut flora pretreatment with synbiotics was able to effectively protect against endotoxin/bacterial translocation, as well as liver damage in the course of acute pancreatitis and concomitant heavy alcohol consumption. The beneficial effect of synbiotics on liver histology seems to be correlated with endotoxemia. Metronidazole did not produce such a beneficial effect; in fact, it further worsened liver damage when alcohol was added to the background of ongoing acute pancreatic inflammation.  相似文献   
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