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101.
The efficacy of subcutaneous recombinant human erythropoietin (rhEPO) (500 U/kg; administered twice a week during the 3 weeks before surgery) in the recovery of preoperative hemoglobin concentrations within a 3- week period was studied in 40 patients, each of whom donated 2 units (900 mL) of blood for their own use before total hip replacement surgery. Twenty autologous blood donors received rhEPO (EPO group) and 20 were not treated (control group). The initial hemoglobin concentration (14.0 +/− 1.0 g/dL [140 +/− 10 g/L]) was completely recovered before surgery (14.0 +/− 1.6 g/dL [140 +/− 16 g/L]) in the EPO group, while a decrease from 13.8 +/− 1.1 to 12.2 +/− 1.3 g per dL (138 +/− 11 to 122 +/− 13 g/L) was observed in the control group. The preoperative reticulocyte count showed more than sixfold increase in the EPO group, whereas a twofold to threefold increase was found in the control group. Serum ferritin concentration fell to 42 +/− 29 micrograms per L in the EPO group and to 54 +/− 35 micrograms per L in the control group. The postoperative serum erythropoietin concentration in the EPO group was significantly lower than that in the control group, but it did not differ from the pretreatment value and was attended by a higher hemoglobin concentration after surgery. Only transient flu-like symptoms were mentioned by patients who were treated with rhEPO. Changes in blood pressure or platelet count or other adverse events were not observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
102.
Two patients are described in whom clinically significant red blood cell alloantibodies could be demonstrated only by in vivo 51chromium (51Cr) survival studies. The first patient had experienced a severe delayed hemolytic transfusion reaction to four units of crossmatch compatible blood. Serial phenotype studies suggested the presence of a serologically undetectable anti-c (hr') antibody. 51Cr survival of c- positive red blood cells was one per cent at 24 hours, while survival of c-negative red blood cells was 80 per cent at 24 hours. The second patient had multiple red blood cell alloantibodies. An anti-c antibody was suspected but could not be convincingly demonstrated by in vitro techniques. 51Cr survival of c-positive red blood cells, however, was 57 per cent at 24 hours and 17 per cent at 48 hours. 51Chromium red blood cell survival studies should be considered whenever an unexplained hemolytic transfusion reaction occurs, or when an expected red blood cell alloantibody cannot be demonstrated by in vitro laboratory studies.  相似文献   
103.
104.
The effect of prestorage irradiation on posttransfusion red cell survival   总被引:1,自引:0,他引:1  
Transfusion-associated graft-versus-host disease (TA-GVHD) may occur whenever immunologically competent allogeneic lymphocytes are transfused to an immunocompromised recipient. Irradiation of blood components eliminates the risk of TA-GVHD but may damage the cellular elements in the transfused component, particularly if the cells are stored for prolonged periods in the irradiated state. To study the effect of irradiation on long-term storage of red cells, AS-1 red cells from eight normal subjects were prepared on two occasions. On one occasion, the units were stored as standard AS-1 red cells for 42 days at 4 degrees C; on the other, they were exposed to 3000 cGy radiation within 4 hours of collection and then were stored as AS-1 red cells for 42 days at 4 degrees C. The donations were at least 12 weeks apart. Irradiated units demonstrated significant elevations in poststorage plasma hemoglobin (Hb) (623 +/- 206 vs. 429 +/- 194 g/dL [6230 +/- 2060 vs. 4290 +/- 1940 g/L], p less than 0.02) and plasma potassium (78 +/- 4 vs. 43 +/- 9 mEq/L [78 +/- 4 vs. 43 +/- 9 mmol/L], p less than 0.01) and significant decreases in red cell ATP (1.9 +/- 0.2 vs. 2.1 +/- 0.3 microM/g Hb, p less than 0.04) and 24-hour posttransfusion red cell recovery (68.5 vs. 78.4%, p less than 0.02), as compared to nonirradiated units. It can be concluded that irradiation with 3000 cGy damages red cells and that long-term storage in the irradiated state may enhance this damage. Red cells should not be stored for 42 days after irradiation with 3000 cGy.  相似文献   
105.
Detailed invasive haemodynamic studies were performed in 27of 32 patients with severe tetanus. Nineteen had severe uncomplicatedtetanus and eight had associated major complications, chieflyinfection and pulmonary complications. The results were comparedwith those obtained from 15 healthy male volunteers who servedas controls. There were two deaths in 32 patients (mortality6.25 per cent). Severe tetanus without major complications wascharacterized by a high output hyperkinetic circulatory statewith tachycardia (heart rate 131 (19.2) beats/minute), increasedstroke volume index (43.1 (10.7) ml/m2), increased cardiac index(5.48 (0.94)1/min/m2) and a normal left ventricular stroke workindex (60.5 (15.9) g/m/m2). Volume loading demonstrated a significanthaemodynamic response and increased vascular capacitance. Evenso the maximum percent rise from baseline values of these indicesafter volume load was significantly higher in controls (p <0.001). Autonomic cardiovascular disturbances affected bothsympathetic and parasympathetic activity. Hypertension and tachycardiaalternating with hypotension and bradycardia were related tosudden fluctuations in systemic vascular resistance. Our studiessuggested some degree of myocardial dysfunction in patientswith severe uncomplicated tetanus. The haemodynamics of severetetanus were masked and altered by complicating infection, pneumonia,and atelectasis.  相似文献   
106.
This article reviews the pathophysiology and pharmacology of emesis in relation to migraine pathogenesis. Also, the place of antiemetic and gastrointestinal prokinetic agents in current and future acute migraine treatment strategies is reviewed. The mechanisms of action of current and novel acute migraine therapies are considered with respect to the neurogenic and vascular hypotheses. Control of migraine-associated nausea and vomiting is often achieved with the benzamide dopamine D2 receptor antagonist metoclopramide. This drug also has 5HT3 receptor antagonist activity and reproducibly stimulates gastric motility to increase the availability of orally administered drugs. Other antiemetic and gastroprokinetic agents with potential value for the treatment of migraine-associated nausea and vomiting could speed absorption of oral antimigraine therapies without central nervous system side effects. Domperidone, a dopamine D2 receptor antagonist that does not cross the blood brain barrier is relatively free of the central side-effect liability of metoclopramide. Cisapride, a benzamide 5HT4 receptor agonist gastrointestinal prokinetic drug, lacks dopamine antagonist activity. A controlled comparison of these agents as migraine co-therapies could provide information on the importance of peripheral and central mechanisms in migraine-associated nausea and vomiting and improve antimigraine treatment options.  相似文献   
107.
自美国国家骨髓库(NMDP)开展第一例无关供者移植以来,至今已有20年.NMDP目前的库容量已逾700万,已为6大洲提供了30 000多份无关供者造血干细胞.这一辉煌成就是美国国家骨髓库600多名工作人员共同努力的结果,同时也得益于广泛的国际合作,包括171个移植中心,73个供者中心,24个脐血库,97个骨髓采集中心,91个血液净化中心,26个HLA分型实验室和26个合作供者登记处.本文回顾了美国国家骨髓库的历史,阐述了20年来移植病人、移植物来源和预处理方案几方面的主要变化趋势.  相似文献   
108.
BACKGROUND: Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi, is endemic to Latin America and may be transmitted in the United States via blood donated by infected immigrants. Blood- borne pathogens such as T. cruzi require supplemental testing for confirmation of seroreactivity. STUDY DESIGN AND METHODS: A study was undertaken to determine an optimal scheme for confirmation of seroreactivity in repeatedly reactive samples identified by the Chagas antibody enzyme immunoassay (EIA). The procedure for initial confirmation involves three purified antigens coated onto three separate polystyrene beads and uses an EIA format. If the sample is reactive with two of three or three of three antigens, it is confirmed as seroreactive. If none or one of three beads is reactive, the sample is indeterminate and subjected to a radioimmunoprecipitation assay (RIPA). The RIPA must demonstrate characteristic bands at 32, 34, and 90 kDa. RESULTS: When tested with sera from persons with potentially cross-reactive diseases (n = 39) or against a presumed negative population from southeast Wisconsin (n = 289), the confirmatory EIA had a specificity of 100 percent. Sensitivity was 100 percent (28/28) with xenodiagnosis-positive sera and 97.6 percent (80/82) with chagasic sera from Latin America. The RIPA showed a specificity of 100 percent in EIA- nonreactive samples (n = 100) and a sensitivity of 100 percent with both xenodiagnosis-positive (28/28) and chagasic (82/82) sera. CONCLUSION: The confirmatory EIA and the RIPA together provide a highly specific and sensitive means of confirming seroreactivity for antibodies to T. cruzi.  相似文献   
109.
110.
Human enteric viruses are detected frequently in various types of environmental water samples, such as irrigation water, wastewater, recreational water, ground or subsurface water and even drinking water, constituting a primary source of gastroenteritis or hepatitis outbreaks. Only a few, but still infective number of viral particles are normally present in water samples, therefore an efficient virus concentration procedure is essential prior to molecular detection of the viral nucleic acid. In this study, a novel chromatographic technology, Convective Interaction Media®(CIM) monolithic supports, were optimized and applied to the concentration of hepatitis A virus (HAV) and feline calicivirus (FCV), a surrogate of norovirus (NoV), from water samples. Two-step real-time RT-qPCR was used for quantitation of the virus concentration in the chromatographic fractions. Positively charged CIM QA (quaternary amine) monolithic columns were used for binding of HAV and FCV present in previously inoculated 1.5 l bottled water samples. Column bound viruses were eluted from the monolith using 1 M NaCl to a final volume of 15 ml. Elution volume was concentrated further by ultracentrifugation. When the CIM/ultracentrifugation method was compared with another concentration method employing positively charged membranes and ultrafiltration, the recovery of HAV was improved by approximately 20%.  相似文献   
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