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911.
BC McLeod ; TH Price ; H Owen ; D Ciavarella ; I Sniecinski ; MJ Randels ; JW Smith 《Transfusion》1998,38(10):938-943
BACKGROUND: Apheresis donation is considered safe, but the incidence of adverse effects has not been determined in a large multicenter series of donations with modern instruments. STUDY DESIGN AND METHODS: The Hemapheresis Committee of the American Association of Blood Banks devised a uniform questionnaire that asked about 32 specific adverse effects. Transient paresthesia and mild vasovagal events were excluded. A survey was conducted in 1995; 17 centers returned 19,611 responses concerning 250 to 2,000 consecutive apheresis donations per center. RESULTS: Six hundred adverse effects were reported in 428 donations (2.18% of donations). Pain or hematoma at a venipuncture site was the most common response (1.15% of donations); only 203 donations had other (nonvenipuncture) adverse effects (1.04%). Total and nonvenipuncture rates were, respectively, 4.84 and 2.92 percent for 2,295 first donations and 1.78 and 0.77 percent for 17,303 repeat donations (p < 0.001). Rates of nonvenipuncture symptoms in first and repeat donations were, respectively, citrate-induced nausea and/or vomiting, 0.87 and 0.27 percent; tetany, 0.09 and 0.04 percent; pallor and/or diaphoresis, 1.87 and 0.32 percent; vasovagal nausea and/or vomiting, 0.87 and 0.13 percent; syncope and/or seizure, 0.39 and 0.04 percent; and chills and/or rigors, 0.31 and 0.01 percent. The overall rate of donor unconsciousness was 0.08 percent. Hemolysis was reported twice. Clotting or leakage occurred in 0.08 percent of donations, and inability to return blood occurred in 0.16 percent. No life-threatening adverse effects were reported. Procedure-specific nonvenipuncture rates were 1.05 percent of 17,584 platelet donations, 0.67 percent of 594 white cell donations, and 0.37 percent of 1,354 plasma donations. Center-specific rates varied from 0.32 to 6.81 percent of donations for total adverse effects and from 0.11 to 2.92 percent of donations for nonvenipuncture events. CONCLUSION: Apheresis donation is a safe undertaking, suitable for voluntary blood donors, with a very low risk of serious adverse effects. The risk of unconsciousness is lower than that found in many studies of whole-blood donation. 相似文献
912.
The common 'thermolabile' variant of methylene tetrahydrofolate reductase is a major determinant of mild hyperhomocysteinaemia 总被引:11,自引:0,他引:11
Harmon DL; Woodside JV; Yarnell JW; McMaster D; Young IS; McCrum EE; Gey KF; Whitehead AS; Evans AE 《QJM : monthly journal of the Association of Physicians》1996,89(8):571-577
Mild hyperhomocysteinaemia is a major risk factor for vascular disease and
neural tube defects (NTDs), conferring an approximately three-fold relative
risk for each condition. It has several possible causes: heterozygosity for
rare loss of function mutations in the genes for 5,10-methylene
tetrahydrofolate reductase (MTHFR) or cystathionine-&bgr;-synthase
(CBS); dietary insufficiency of vitamin co-factors B6, B12 or folates; or
homozygosity for a common 'thermolabile' mutation in the MTHFR gene which
has also been associated with vascular disease and NTDs. We quantified the
contribution of the thermolabile mutation to the hyperhomocysteinaemic
phenotype in a working male population (625 individuals). Serum folate and
vitamin B12 concentrations were also measured and their relationship with
homocysteine status and MTHFR genotype assessed. The homozygous
thermolabile genotype occurred in 48.4, 35.5, and 23.4% for the top 5, 10
and 20% of individuals repectively) ranked by plasma homocysteine levels,
compared with a frequency of 11.5% in the study population as a whole
establishing that the mutation is a major determinant of homocystein levels
at the upper end of the range. Serum folate concentrations also varied with
genotype, being lowest in thermolabile homozygotes. The MTHFR thermolabile
genotype should be considered when population studies are designed to
determine the effective homocysteine-lowering dose of dietary folate
supplements, and when prophylactic doses of folate are recommended for
individuals.
相似文献
913.
Fibrin glue: the perfect operative sealant? 总被引:12,自引:0,他引:12
914.
Selective plasma filtration with a hollow-fiber membrane device was compared prospectively to plasma exchange in the therapy of a patient with homozygous familial hypercholesterolemia. Four liters of patient plasma was removed biweekly during each of six consecutive plasma exchanges, after which 20 consecutive biweekly 4-liter filtration procedures were conducted. The hollow-fiber membrane retained 94 percent of the low-density lipoprotein (LDL) cholesterol presented to it, and allowed passage of 83 percent of the albumin, 68 percent of the IgG, and 47 percent of the high-density lipoprotein (HDL) cholesterol. Both plasma exchange and plasma filtration decreased the patient's total and LDL cholesterol levels by 80 percent. However, filtration removed significantly less HDL than did exchange (54 versus 71% reduction in HDL levels, respectively); preserved significantly higher levels of IgG, clotting factors, and complement components; and avoided the need for expensive albumin replacement solutions. In addition, the patient tolerated the filtration procedures significantly better than the exchanges. Newer apheresis techniques that selectively deplete plasma of LDL cholesterol, such as secondary membrane filtration, are likely to replace plasma exchange as the therapy of choice in patients with homozygous hypercholesterolemia. 相似文献
915.
目的:差分回归分析技术适用于生理学相关函数未知的复杂脑高级功能的功能磁共振成像研究,实验应用差分回归分析技术观察人脑嗅觉活动时相关中枢的动态激活区。方法:实验于2005-11/2006-01完成。选择对13例右利手、无嗅觉障碍的健康志愿者进行嗅觉刺激功能磁共振成像实验。①实验方法:刺激方式采用组块设计,先给予30次Scan(S)刺激,再给予第二次刺激15次S,之间有55次S作为控制任务;每位被试先给予愉快气体(乙酸戊酯),间隔足够长时间后,再给非愉快气体(吡啶)。采用GE Signa 1.5T echospeed MR/i磁共振成像系统进行功能图像扫描。②数据分析:在AFNI平台上,数据经头动校正、空间标准化、空间平滑等处理后,再用差分回归分析技术进行数据处理和分析获得嗅觉实验脑激活图。阈值P=0.005。结果:11例受试者的数据进入结果分析。①嗅觉实验激活脑区(双侧皆有)为海马、眶额回、丘脑背内侧核、扣带回的背侧及喙、杏仁核、前额叶及额内侧回、颞叶、岛叶、枕叶、脑干和小脑,各脑区反应时间均较刺激时间有不同程度的延后。②愉快气体与非愉快气体激活的脑区无显著差异(P>0.005),均以右侧大脑半球激活明显(P<0.005)。结论:差分回归分析技术是嗅觉等复杂的脑功能研究可行的实验分析方法,人脑嗅觉刺激是复杂的延迟反应过程,右侧大脑半球为嗅觉"优势半球"。 相似文献
916.
DR Henrard ; P Berthillon ; JW Scheffel ; PL Ladaique ; BS Moore ; MC Pailhous ; PH Finetti ; C Trepo 《Transfusion》1998,38(2):194-198
BACKGROUND: A group of 290 transfusion recipients enrolled in a prospective study of posttransfusion hepatitis was studied to determine the possibility of previously unrecognized hepatitis C virus (HCV) transmission. STUDY DESIGN AND METHODS: Before and after transfusion, blood specimens that were negative in first-generation enzyme immunoassay (EIA) were tested by current commercial EIAs, several single-antigen research EIAs, and supplemental tests. RESULTS: Current second- and third-generation EIAs identified five subjects (1.7% of total) who had chronic hepatitis C before transfusion. Twenty additional sera had some reactivity with research EIAs. However, those results were the same before and after transfusion (n = 7), had reverted to partially reactive or nonreactive (n = 8), or could not be confirmed by serologic tests or polymerase chain reaction in follow-up specimens (n = 5). CONCLUSIONS: Transient or restricted reactivity to HCV antigens measured by more sensitive research EIAs does not seem to correspond to recent HCV transmission by transfusion. Whether such reactivity could reflect remote HCV infection, with the potential for chronic or intermittent viremia, remains to be determined. 相似文献
917.
S Anwar MB KG Davies FRCS B Tejura MB AET White FRCS JW Neal MRCPath C Lane FRCS 《International journal of clinical practice》1995,49(2):102-104
SUMMARY A case is presented of a pseudotumour that developed in the left orbit 4 years after surgery and histological confirmation of a pseudotumour in the right orbit. There was no evidence of any thyroid pathology. 相似文献
918.
大学生自尊特点与性别、年级及心理因素的关系 总被引:1,自引:0,他引:1
目的:观察大学生自尊水平的特点。方法:于2005-11/2006-05选取江西省内6所高等院校,专业包括理工科、医学、师范类及文科类大学生793名。以751名大学生为研究对象,采用二维自尊量表进行调查,包含16个题项,每个维度8个题项。量表的重测信度为0.84和0.80,同质性信度为0.86和0.84;该量表测量整体自尊,分为自我喜欢和自我能力感两个维度。采用个别访谈的方法对自尊高分同学和自尊低分同学进行个别访谈,同时收集同学和班主任(辅导员)对该同学的评价。调查中使用半结构化访谈,访谈提纲的内容是依据症状自评量表各因子结合以往研究中自尊及其相关影响因素设计的,主要包括以下3个方面:①与焦虑有关的认知和事件。②与同学、老师以及朋友的关系。③对自我情感和心境的评价。为了缓解被访谈者的紧张情绪,还进行其他方面的交流。结果:发放问卷793份,收回780份。对所收回的问卷进行初步整理,剔除不符合要求的废卷后,获得有效问卷751份。①男生在整体自尊和自我能力感维度上得分高于女生,差异有显著性意义[分别为(49.5820±7.9979),(48.2091±8.2642)分;(23.3893±3.9680),(22.6963±4.2606)分,t=2.157,2.134,P<0.05]。男女生在自我喜欢维度上得分差异无显著性意义(P>0.05)。②在整体自尊和自尊两个维度上,各年级之间差异有显著性意义(P<0.05)。大二学生自我喜欢维度得分明显高于大一和大三学生[分别为(26.7353±5.1527),(25.2432±4.7695),(25.6045±5.2917)分,t=3.485,2.11,P<0.05,0.01];大二学生在自我能力感维度得分明显高于大一和大三学生[分别为(23.5588±4.2219),(22.5459±4.2285),(22.9718±3.9448)分,t=2.748,1.395,P<0.05,0.01]。③整体自尊和自尊两个维度,在性别与年级之间有交互效应。整体自尊和自我喜欢得分男生高于女生,大二学生得分高于大一和大三学生。自我能力感得分大二女生高于男生。在整体自尊和自尊两个维度,年级和专业之间有交互效应。④自尊与心理健康的关系:整体自尊高分者普遍具有正确的人生态度,满意的心境,对生活乐观,对未来充满了希望,和谐的人际关系、良好的个性和高尚的人格,同学之间关系融洽,能很好地相处,在与人交往中能做到尊重人、理解人,从不将自己的观点强加到他人的身上,能够平等地、宽容地了解、评价对方。而整体自尊低分者普遍存在焦虑情绪,人际关系不和谐和不能恰当地认同自己,或是莫名其妙地自傲,或是无缘无故地自卑,经常有意无意地掩饰自己的不足,心理特别敏感、脆弱,失落感极强,经不起风浪的折腾,存在严重的心理冲突,回避矛盾,无法保持平衡的心理状态。结论:大学生自尊水平存在性别、年级差异,并与心理健康症状存在明显相互作用关系。 相似文献
919.
Nonrandom chromosome abnormalities in acute leukemia and dysmyelopoietic syndromes in patients with previously treated malignant disease 总被引:14,自引:2,他引:14
Cytogenetic studies were performed on 26 patients who developed acute nonlymphocytic leukemia (ANLL) or a dysmyelopoietic syndrome after treatment of a primary malignancy. Fifteen patients had radiotherapy and chemotherapy, seven had only chemotherapy, and four had only radiotherapy. The median times from diagnosis of the initial disease to the development of bone marrow dysfunction for these treatment groups were 50, 46, and 49 mo, respectively. Twenty-five patients had an abnormal karyotype in myeloid cells. Loss of part or all of no. 5 and/or no. 7 was noted in 23 of 25 patients with aneuploidy. Loss of no. 5 was noted only in patients who previously had malignant lymphoma, whereas loss of no. 7 was seen in these patients as well as in those who had other malignancies. Abnormalities of both nos. 5 and 7 occurred in 53% of the patients treated with combined therapy and in only 27% of patients treated with either modality alone. Although these changes are distinctly different from those noted in lymphomas, they are similar to those seen in 25% of aneuploid patients with ANLL de novo. 相似文献
920.
M Adams ; TH Lee ; MP Busch ; J Heitman ; GJ Marshall ; GF Gjerset ; JW Mosley 《Transfusion》1993,33(6):504-508
Storage of lymphocytes for later use in prospective epidemiologic studies of blood donors and transfusion recipients has been limited by the cost of separating peripheral blood mononuclear cells (PBMCs). When the Transfusion Safety Study began in 1985, it was decided to establish a cell repository of cryopreserved buffy coat (BC) samples, and thus far over 20,000 samples have been accumulated from enrolled subjects. To determine if these specimens could be used for polymerase chain reaction, a simple thawing and pelleting technique for recovering hemoglobin-free total white cells (WBCs) was developed. To validate the technique, parallel analysis was conducted of BCs, whole blood (WB), and PBMC samples from human immunodeficiency virus type 1 (HIV-1)- seropositive subjects. Immediate postthaw cell courts of 29 frozen- thawed (F-T) WB and BC samples averaged 90 percent of the prefreeze (input) values. Representative WBC populations were obtained by immediate pelleting. Amplification of HIV-1 gag sequences from F-T BCs and F-T WB was 94 and 75 percent, respectively, which is as sensitive as that obtained with freshly separated PBMC lysates. Quantitative HIV- 1 proviral load analysis by serial dilution of 23 F-T BCs and 8 WB lysates showed results comparable to those obtained with lysates of fresh PBMCs. Values for WBC differential and immunophenotyping could be applied to express viral load relative to total WBCs, PBMCs, or CD4+ cells. These results establish the basis for simplified virologic analysis of cryopreserved BC or WB specimens. 相似文献