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241.
242.
BACKGROUND: A good blood bank must be able to provide compatible blood units promptly to operating room patients with minimal wastage. A "self- service" by nursing staff blood banking system that is safe, efficient, and well-accepted has been developed. STUDY DESIGN AND METHODS: Specific blood units are no longer assigned to surgical patients who have a negative pretransfusion antibody screen, irrespective of the type of surgery. A computer-generated list of the serial numbers of all group-identical blood units currently in the blood bank inventory is provided for each patient. The units themselves are not labeled with a patient's name. The group O list will be provided for group O patients, the group A list for group A patients, and so forth. Should the patient require transfusion during surgery, the operating room nurses go to the refrigerator, remove any group-identical unit, and check the serial number of the unit against the serial numbers on the patient's list. If the serial number is on that list, the blood bank will accept responsibility for compatibility. The system was implemented in 1995. RESULTS: Since implementation, a total of 2154 patients have undergone operations at this hospital. Thirty-two patients received more than 10 units of red cells each. There were no transfusion errors. The crossmatch-to-transfusion ratio was reduced from 1.67 to 1.12. Turnaround time for supplying additional or urgent units to patients in operating room was shortened from 33 to 2.5 minutes. There was no incidence of a blood unit's serial number not being on the list. Work by nurses and technical staff was reduced by nearly 50 percent. CONCLUSION: The "self-service" (by nursing staff) blood banking system described is safe and efficient. It saves staff time and can be easily set up.  相似文献   
243.
肺泡液体主动转运及肺水通道的实验研究   总被引:14,自引:1,他引:14  
目的 研究肺水通道蛋白1,4(AQP1,4)对肺泡毛细血管间不通透性和压力性肺水肿的影响,肺泡液体主动转运对肺泡液体清除(AFC)的影响,以及不同pH条件下大鼠AFFC的变化。方法采用表面荧光技术和重力方法研究小鼠肺泡毛细血管间水通透性及水通道蛋白与压力性肺水肿的关系;测定大鼠肺泡灌注液中同位素标记白蛋白浓度推测AFC变化。应用低pH溶液灌注在鼠肺透发肺损伤,并测定不同pH条件下AFC变化。结果 AQP1敲除可减轻小鼠肺泡毛细血管间水通透性和压力性肺不肿的程度。沙丁胺醇可促进AFC,合用心得安可抑制其作用。当大鼠肺泡灌注液pH>2.5时,间羟叔丁肾上腺素、异丙肾上腺腺、沙美特罗均可促进AFC,Na通道抑制剂Benzamil可抑制AFC。结论 AQP1敲除明显降低小鼠肺泡毛细血管间水通透性,轻度减压力性肺水肿。β肾上腺能激动促进机械通气大鼠AFC。AFC的前提是完整肺泡上皮的存在,当pH低于2.5时,促进AFC的作用被肺损伤作用掩盖。  相似文献   
244.
BACKGROUND: B-type natriuretic peptide (BNP) and 6-min walk test (6MWT) are both related to the severity and prognosis in chronic heart failure (CHF), but may reflect different aspects of CHF. We related BNP and 6MWT to left ventricular ejection fraction (LVEF), New York Heart Association functional class (NYHA), and two indices of quality of life (physical subscales): the Minnesota Living with Heart Failure Questionnaire (MLwHFQph) and the RAND-36ph. METHODS: Plasma BNP and 6MWT were measured at discharge in 229 patients who had been admitted for CHF. LVEF and NYHA were determined, and patients completed the MLwHFQ and RAND-36 questionnaires. RESULTS: BNP was weakly correlated to LVEF (r=-0.29, P<0.01) and NYHA (r=0.20, P<0.01), but not to MLwHFQph and RAND-36ph. On the other hand, 6MWT is related to MLwHFQph (r=-0.23, P<0.01), RAND-36ph (r=0.52, P<0.01), and NYHA (r=-0.46, P<0.01), but not to LVEF (r=-0.15, P=0.05). There is also no correlation between BNP and 6MWT (r=-0.01, P=0.87). CONCLUSIONS: The present data show that BNP and 6MWT represent different aspects of the clinical syndrome of CHF. The outcomes of this study suggest that BNP plasma levels are more related to cardiac function, while 6MWT reflects functional capacity and quality of life.  相似文献   
245.
The development of transvenous ventricular pacing leads with proximal electrodes capable of atrial sensing and the recent availability of smaller generators has created the opportunity to treat children with complete AV block and normal sinus node function with a transvenous single lead VDD pacing system. Studies in adults have demonstrated this system to be efficacious with low complication rates. Transvenous single lead VDD pacemakers were implanted in ten children, aged 5–15 years, between December 1993 and April 1996, in our institution. The indications were complete AV block with severe bradycardia in 5 patients, second-degree or complete A V block following congenital heart surgery in 3, complete A V block with long QT syndrome in 1, and second-degree AV block and syncope in 1. There were no complications related to the procedure in any case. P and R wave amplitudes were measured and thresholds were determined intraoperatively on all patients. Amplitudes and thresholds were remeasured on seven patients with a mean follow-up of 17 months; Holter monitors were performed on seven patients with a mean follow-up of 16 months. P and H wave amplitudes were generally diminished at follow-up compared to initial values but remained within an acceptable range for all patients. Four patients required reprogramming after pacemaker insertion, 1 received an atrial lead for dual chamber pacing, 1 required repositioning for lead dislodgment. and 1 patient required a new lead for an inadequate ventricular pacing threshold. No patient had evidence of failure to sense or capture as evaluated by Halter monitoring at last follow-up. Single lead VDD pacing systems can be successfully used in properly selected children with high degree or complete AV block with normal sinus node function.  相似文献   
246.
Immunologic characterization of a helper T-cell lymphoma   总被引:3,自引:0,他引:3  
The lymphocytes of a patient with a T-cell non-Hodgkin's lymphoma with peripheral blood involvement and polyclonal hypergammaglobulinemia were characterized in terms of surface markers and immunologic functions. Using the fluorescence-activated cell sorter and employing various monoclonal antibodies against T-cell surface antigens, it was shown that almost all of the patient's peripheral blood lymphocytes were positive for OKT4 and 9.3, antibodies that recognize helper T-cell subset. The circulating lymphoma cells had typical characteristics for T cells; they formed spontaneous rosettes with sheep erythrocytes and stained with the pan-T-cell antibodies 9.6 and 10.2, but did not react with other anti-T-cell monoclonal reagents such as OKT3, UCHT-1, and 3A1. The cells appeared to be mature by the fact that they did not stain with OKT6, and terminal deoxynucleotidyl transferase was undetectable. Functionally, they were able to provide "help" for antibody production, and they could be stimulated to produce moderate amounts of interleukin-2, while unable to proliferate in response to mitogens. Morphologically, some of the lymphocytes showed a deeply cleaved nucleus.  相似文献   
247.
Although molecular biologic techniques can now detect minimal numbers of residual cancer cells in patients in complete clinical remission, the clinical significance of minimal residual disease has never been conclusively established. If the detection of minimal residual disease predicts which patients will relapse, then therapy could be altered based upon the detection of these cells. The t(14;18) can be detected by polymerase chain reaction (PCR) amplification in 50% of patients with B-cell non-Hodgkin's lymphoma and allows detection of one lymphoma cell in up to 1 million normal cells. To determine the clinical significance of the detection of minimal residual lymphoma cells in the bone marrow (BM) PCR amplification was used to detect the presence of residual lymphoma cells after autologous BM transplantation (ABMT) in serial BM samples from 134 patients with B-cell lymphoma in whom a bcl- 2 translocation could be detected. PCR analysis was performed on a total of 542 BM samples obtained while these patients were in complete remission. Disease-free survival was markedly increased in patients with no PCR-detectable lymphoma cells in the marrow compared with those in whom residual lymphoma cells were detected (P < .00001), and the presence of detectable lymphoma cells was associated with a 48-fold increase in the risk of relapse. Of the 77 patients (57%) with no PCR- detectable lymphoma cells in their most recent BM sample, none have relapsed. In contrast, all 33 patients (25%) who have relapsed had PCR- detectable lymphoma cells detected in their BM before clinical relapse occurred. In 19 patients (14%), residual lymphoma cells in the BM were detected early following transplantation and subsequently were no longer detectable, although these patients received no further therapy. In these patients, residual lymphoma cells may already have been irreversibly damaged by the high-dose therapy or an endogenous immune mechanism may be capable of eliminating residual lymphoma cells in some patients. Therefore, although the detection of minimal residual disease by PCR following ABMT in patients with lymphoma identifies those patients at high risk of relapse, the presence of residual minimal disease early after transplantation may not be associated with poor prognosis in a small subset of patients. Confirmatory studies will be required to determine more definitively the role of minimal disease detection to identify which patients require additional therapy.  相似文献   
248.
One hundred and twenty-eight patients with non-Hodgkin's lymphoma (NHL), Hodgkin's disease (HD), and acute lymphoblastic leukemia (ALL) previously reported from a phase III trial of rhGM-CSF or placebo following autologous bone marrow transplantation (ABMT) were investigated for the development of late toxicities. Median follow-up is 36 months. No apparent long-term deleterious effects on BM function were observed. Moreover, disease-free survival and overall survival were similar for patients on both treatment arms, arguing for the long- term safety of recombinant human granulocyte macrophage-colony- stimulating factor (rhGM-CSF). The only factors predictive for both a high risk of relapse over time and mortality were having the diagnosis of ALL and/or undergoing ABMT in resistant relapse. We attempted to identify clinical variables before BM harvest, at the time of marrow infusion, or events within the first 100 days posttransplant, which might predict speed of neutrophil recovery in the setting of placebo or rhGM-CSF administration after ABMT. Only previous exposure to agents that deplete stem cells led to a significant delay in neutrophil recovery, suggesting their avoidance in patients who may undergo ABMT. Nevertheless, even those patients benefited from rhGM-CSF. For all patients, rhGM-CSF and agents that deplete stem cells were the strongest independent predictors for neutrophil engraftment. With the increasing use of newer hematopoietic growth factors both alone and in combination, long-term follow-up is essential to confirm the same safety that we report with rhGM-CSF.  相似文献   
249.
Ninety-nine consecutive patients with acute leukemia in first complete remission under age 50 (median age 27 years; age range 1 to 47 years) with a histocompatible sibling donor were treated with fractionated total body irradiation (1,320 cGy) and high-dose etoposide (60 mg/kg) followed by allogeneic bone marrow transplantation. Sixty-one patients were diagnosed with acute myelogenous leukemia (AML), 34 patients with acute lymphoblastic leukemia (ALL), 3 patients with biphenotypic acute leukemia, and 1 patient with acute undifferentiated leukemia. Thirty of the 34 patients with ALL had at least one of the following high-risk factors: age greater than 30, white blood cell count at presentation > 25,000/microL, extramedullary disease, certain chromosomal translocations, or the need for greater than 4 weeks of induction chemotherapy to achieve first complete remission. Cumulative probabilities of disease-free survival and relapse at 3 years were 61% and 12%, respectively, for the 61 patients with AML and 64% and 12%, respectively, for the 34 patients with ALL. By stepwise Cox regression analysis, significant prognostic variables for patients with acute myelogenous leukemia were the presence of acute graft-versus-host disease and increasing age, whereas for patients with acute lymphoblastic leukemia, significant variables were age and the development of cytomegalovirus-associated interstitial pneumonia. Complications related to graft-versus-host disease and relapse of leukemia were the major causes of death.  相似文献   
250.
Guidelines on heart failure (HF) stress the importance of lifestyle advice, although there is little evidence that such recommendations improve symptoms or prognosis. Patients experience symptoms of different intensities which impair their daily activities and reduce the quality-of-life. To cope with their clinical condition, many patients seek advice about lifestyle and self-management strategies when in contact with medical care providers, particularly specialized HF services. Self-care management is an important part of HF treatment, thus health professionals working with patients with HF have recognized the need for more specific recommendations on lifestyle advice. The present paper summarizes the available evidence, promotes self-care management, and aims to provide practical advice for health professionals delivering care to HF patients. It also defines avenues of research to optimize self-care strategies in a number of key areas to derive further benefits.  相似文献   
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