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101.
102.
Monitoring for undertransfusion 总被引:1,自引:0,他引:1
BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components. 相似文献
103.
Stanworth SJ; Bhavnani M; Chattopadhya C; Miller H; Swinson DR 《QJM : monthly journal of the Association of Physicians》1998,91(1):49-56
Felty's syndrome (FS) (rheumatoid arthritis with neutropenia and
splenomegaly) has a poor prognosis, largely because of the high risk of
severe infection. Granulocyte colony-stimulating factor (G-CSF) is an
emerging treatment for chronic neutropenia. We prospectively monitored its
use in eight patients with recurrent infections or who required joint
surgery. Significant side-effects were documented in five, including
nausea, malaise, generalized joint pains, and in one patient, a vasculitic
skin rash. In two patients treatment had to be stopped, and in these cases
G-CSF had been started at full vial dosage (300 micrograms/ml filgrastim or
263 micrograms/ml lenograstim) alternate days or daily. G-CSF treatment was
continued in three patients by restarting at reduced dose, and changing the
proprietary formulation. G- CSF raised the neutrophil count, reduced severe
infection, and allowed surgery to be performed. A combined clinical and
laboratory index suggested that long-term treatment (up to 3.5 years) did
not exacerbate the arthritis. Once on established treatment, it may be
possible to use smaller weekly doses of G-CSF to maintain the same clinical
benefit. One of the three patients whose FS was associated with a large
granular T-cell lymphocytosis showed a reduction in this subset of
lymphocytes during G-CSF treatment.
相似文献
104.
Long-term follow-up testing of red cell alloantibodies 总被引:1,自引:0,他引:1
BACKGROUND: In previous studies, 29 to 34 percent of potentially hemolytic red cell antibodies were not detected after short-term follow- up. STUDY DESIGN AND METHODS: To examine long-term detection, records were reviewed for 44 consecutive patients who were tested more than 5 years after their potentially hemolytic red cell antibodies were first identified in this hospital. RESULTS: After 5 to 10 years, 14 (39%) of 36 Rh, Kell, and Duffy system antibodies were not detected on at least one occasion. Twenty-two other such antibodies were sought again after more than 10 years; 10 (45%) were not detected. When restimulation by pregnancy was excluded, these rates were 42 and 48 percent, respectively. CONCLUSION: Clinically significant red cell antibody formation is probably more common than previously realized, because nearly half of these antibodies are undetected after long-term follow- up. 相似文献
105.
Severe malaria in children in Papua New Guinea 总被引:1,自引:0,他引:1
Allen SJ; O'Donnell A; Alexander ND; Clegg JB 《QJM : monthly journal of the Association of Physicians》1996,89(10):779-788
The clinical features of severe falciparum malaria and risk factors for
mortality were studied in 489 children admitted with malaria to Madang
Hospital, Papua New Guinea. The most common severe manifestations of
malaria were severe anaemia (22%) and coma (16%). Children with severe
anaemia were younger than those with coma (median age 2.2 vs. 3.7 years)
and had been ill for longer before admission (median 7 vs. 4 days,
respectively). Although the clinical features of coma in Madang children
with malaria resembled closely those reported in African children,
mortality was lower (8% vs. 17-25%, respectively). Overall, 17 (3.5%)
children died, most within 12 h of admission. A high level of plasma
lactate (> or = 5 mmol/l) was common (20%) and was the major predictor
of death in multiple regression analysis. Raised plasma creatinine and
decreased plasma bicarbonate were also independent predictors of mortality.
Coma was not predictive of death, although a high proportion of children
with profound coma died. Investigation of the causes of acidosis in
children with malaria is a high research priority. In view of the short
time interval between admission and death in many children, emphasis must
be placed on the prevention or early recognition and treatment of acidosis
in the district health clinic as well as the central hospital.
相似文献
106.
Rising demand for single-donor platelet components–from random donors, to maintain platelet inventories, or from HLA-compatible donors, to support alloimmune platelet-refractory patients–necessitated increasing the size of a community plateletpheresis donor registry. This study compares two strategies for recruiting whole-blood donors into a plateletpheresis program. The whole-blood donors who were asked to participate in this study had recently joined an unrelated bone marrow donor registry and had been HLA-typed as part of that process. An in-person recruitment strategy, which was time-intensive for the apheresis donor coordinator, served as the standard. A by-mail strategy involved the mailing of recruitment materials to marrow-donor registry participants. Marrow-donor registry participants were approached about apheresis participation after they had indicated an interest in the plateletpheresis program by returning a tear-off section of an informational brochure that was sent to them along with their marrow- donor registry materials. A total of 852 marrow-donor registry participants were randomly assigned to one of two recruitment strategies, and the recruitment rates were the same (46%) for both methods. In addition, levels of apheresis participation and attrition rates of donors recruited by either strategy were comparable. Thus, the simple strategy of mailing information about a plateletpheresis program is a very cost-effective method of recruiting donors. 相似文献
107.
PD Issitt ; MR Combs ; SJ Bredehoeft ; ML Campbell ; M Heimer ; L Joyner ; L Lorentsen ; C Remley ; S Bullock ; J Bumgarner ; et al. 《Transfusion》1993,33(4):284-293
In a retrospective study on samples from 10,000 recently transfused patients, 35 samples were found to contain an antibody that reacted with ficin-treated red cells but was not demonstrable by low-ionic- strength saline solution and indirect antiglobulin test (LISS-IAT). In those 35 patients, the specificity of the antibody was such that each patient would have been transfused with antigen-negative blood had the antibody reacted in LISS-IAT. Tests on red cells from the units already transfused showed that 19 patients had among them received, by chance, 32 antigen-positive and 74 antigen-negative units. The remaining 16 patients had among them received 57 units that were, again by chance, all antigen negative. One patient given antigen-positive blood suffered a delayed transfusion reaction; in two others the antibodies became LISS-IAT active after transfusion. However, similar changes to the LISS- IAT-active state were seen with two antibodies of patients given only antigen-negative blood. Also found in the 10,000 patients were 28 clinically insignificant antibodies, 77 sera in which the antibody was too weak to identify, and 216 autoantibodies that reacted only with ficin-treated red cells. These data support a belief, generally held in the United States but not necessarily elsewhere, that the use of protease-treated red cells for routine pretransfusion tests creates far more work than the accrued benefits justify. 相似文献
108.
目的:建立人脐静脉内皮及内皮下间充质干细胞体外培养和扩增的方法,探讨其生物学特性,建立间充质干细胞体外培养扩增体系。方法:实验于2006-04/2006-09在辽宁医学院解剖学实验室完成。解剖细胞培养室为无菌百级培养间。正常健康产妇顺产或剖宫产的新生儿脐带由辽宁医学院附属第一医院提供,产妇及其家属均知情同意,并经医院伦理委员会批准。实验方法:①体外分离和培养贴壁细胞:无菌条件下取正常健康产妇分娩或剖宫产脐带,将其用预热PBS充分洗涤去血渍后,从脐静脉一端插入留置针,用预热PBS冲净静脉腔血后,用止血钳夹闭另一端,注入经预热至37℃的Ⅰ型胶原酶,置于37℃水浴箱中消化,30min后放出胶原酶,并用PBS冲洗血管腔,收集消化液和冲洗液,400r/min离心10min,吸弃上清液,重悬于M199培养基(含体积分数为0.15的胎牛血清,2mmol/L谷氨z酰胺,2μg/L碱性成纤维细胞生长因子,100U/mL青霉素,100U/mL链霉素)。以5×108L-1密度接种于6孔培养板中,置于37℃、体积分数为0.05的CO2饱和湿度培养箱中培养,48h后全量换液,以后每3d全量换液。待细胞80%融合时,0.25%胰酶消化,按1×108L-1传代培养。②间充质干细胞生长曲线的测定:取传代培养细胞,按2×107L-1密度接种于24孔培养板内,每天取3孔,将细胞消化计数,连测8d,绘制间充质干细胞生长曲线。③间充质干细胞表面抗原检测:在24孔塑料培养板内放置无菌的盖玻片,每孔中种植108L-1第2代细胞悬液1mL。采用免疫细胞化学方法进行细胞表面抗原检测。结果:①间充质干细胞的形态学观察:接种的细胞48h后细胞完全贴壁生长,其镜下形态有呈椭圆形、多角形的内皮细胞以及呈梭形的成纤维样细胞,有的形成漩涡状生长的集落。②间充质干细胞生长曲线的分析:传代培养的潜伏期约为24~36h,细胞倍增时间约为30~36h,对数增殖期约为二三天,对数增殖期后第5天进入平台期。③间充质干细胞表面抗原特性:免疫细胞化学分析结果显示,间充质干细胞表面抗原cd166、cd44阳性,而vWF阴性,说明分离获得的细胞具有间充质干细胞的特点。结论:所建立的分离和培养方法可获取人脐静脉黏附细胞中一组独特的细胞群,具有间充质干细胞的生物学特性。 相似文献
109.
膈下逐瘀汤对肝癌Bel-7402细胞增殖的抑制及其机制 总被引:1,自引:0,他引:1
目的:观察中药复方膈下逐瘀汤对肝癌Bel-7402细胞增殖的抑制及其相关机制。方法:实验于2005-09/2006-07在南方医科大学细胞生物实验室完成。膈下逐瘀汤(按《医林改错》方组成:五灵脂6g,当归9g,川芎6g,桃仁9g,丹皮6g,赤芍6g,乌药6g,延胡索3g,甘草9g,香附5g,红花9g,枳壳5g。均购自南方医院中药房)经研粉、煮沸、离心、过滤配成质量浓度为25,50,100,200mg/L的药液;顺铂配制成质量浓度为0.5,1.0,1.5,2.0mg/L的药液(作为阳性对照),均作用于Bel-7402细胞,并设空白对照(未加任何药物)。采用甲基噻唑基四唑(methyl thiazoly ltetrazolium,MTT)比色法检测膈下逐瘀汤各组对Bel-7402细胞生长的影响,用酶标仪测定培养细胞在600nm处吸光度值,并计算细胞抑制率,抑制率(%)=(实验组吸光度值-对照组吸光度值/对照组吸光度值)×100%。用蛋白印迹试验检测不同质量浓度药物作用48,72h时第10号染色体同源丢失性磷酸酶-张力蛋白基因蛋白的表达水平。结果:①中药复方膈下逐瘀汤对Bel-7402细胞增殖的影响:膈下逐瘀汤对肝癌Bel-7402细胞有明显的生长抑制作用,呈良好的剂量-效应关系。膈下逐瘀汤质量浓度在200mg/L时其48h细胞生长抑制率介于0.5mg/L顺铂组与1.0mg/L顺铂组之间(分别为41.27%,34.01%,47.49%);膈下逐瘀汤质量浓度在50,25mg/L时,其细胞抑制率明显低于顺铂组,72h细胞抑制率结果基本相同。②药物作用肝癌Bel-7402细胞48h后第10号染色体同源丢失性磷酸酶-张力蛋白基因蛋白的表达:第10号染色体同源丢失性磷酸酶-张力蛋白基因蛋白的表达增多,200mg/L膈下逐瘀汤组介于0.5mg/L顺铂组和1.0mg/L顺铂组之间。结论:中药复方膈下逐瘀汤抑制Bel-7402细胞的增殖机制可能是第10号染色体同源丢失性磷酸酶-张力蛋白基因表达增多的原因。 相似文献
110.
目的:认识影响大学生骨密度的各种生活因子,以便指导大学生提高骨密度,预防骨质疏松症的发生。方法:于2005-07/08选择延边大学医学院在校生自愿者638人,其中朝鲜族男生130人,朝鲜族女生110人,汉族男生196人,汉族女生202人。采用问卷调查方式,调查内容包括被调查者的自然状况、饮食、运动情况及其他与骨密度有关的生活方式。同时对调查对象进行右足跟骨骨密度测定。综合骨评价值=透过指数×超声波传导速度。结果:纳入受试对象638人,均进入结果分析。①汉族男生的综合骨评价值明显低于朝鲜族男生(分别为3.0±0.4,3.2±0.4,P<0.05),女生不存在民族差异。②男生的生活方式与骨密度的关系:注意平衡膳食及摄取充足的豆制品有利于骨密度提高(t=10.693,P<0.01;t=2.483,P<0.05);进行定期的运动(足球、篮球、排球、网球等球类运动和使用健身器)以及中学时期除了上体育课之外进行过体育运动能明显提高骨密度(t=10.693,P<0.01;t=1.998,P<0.05);有骨折史的学生骨密度明显低于无骨折史的学生(t=2.028,P<0.05)。③女生的生活方式与骨密度的关系:经常不吃早餐的学生骨密度低于按时吃早餐的学生(t=6.600,P<0.01);注意均衡饮食和进行定期运动的学生骨密度明显高于不注意均衡饮食和不做定期运动的学生(t=4.149,P<0.01;t=2.992,P<0.01)。③女生中也表现出有骨折史的学生骨密度显著低于无骨折史的学生(t=1.965,P<0.05)。结论:影响大学生骨密度的因素有骨折史、定期运动、均衡饮食、豆制品摄取。 相似文献