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681.
Contribution of cardiometabolic risk factors to estimated glomerular filtration rate decline in Indigenous Australians with and without albuminuria ‐ the eGFR Follow‐up Study 下载免费PDF全文
682.
DM Surgenor ; SV Kevy ; FC Chao ; FJ Lionetti ; DM Kenney ; MS Jacobson ; B Kim ; DH Ausprunk ; IO Szymanski ; LN Button ; et al. 《Transfusion》1990,30(7):605-616
The Initial Blood Storage Experiment (IBSE) probed the behavior of human red cells, white cells, and platelets during exposure to microgravity for 6 days and 2 hours on a National Aeronautics and Space Administration (NASA) shuttle mission, named STS 61-C, which was launched on January 12, 1986. IBSE involved carefully controlled comparisons between two identical sets of blood cells, one exposed to microgravity and the other held on the ground. Specially designed and fabricated, electrically powered environmental chambers provided appropriate environmental temperatures and air flow to support cell metabolism throughout the experiment. To circumvent the need for constant agitation of platelets during storage, a new thin-layer compression method for platelet preservation was developed. Blood cell samples were allocated to the two arms of the experiment, microgravity and earth gravity, by blind assignment. Moreover, to ensure unbiased assessment of the experiment's findings, postexperiment samples for measurement were identified by code. To optimize the chances of detecting possible gravitational effects, a wide array of measurements of cellular function, morphology, metabolism, and immunology were made. Analysis of variance was used in analyzing the data. The most striking finding was that platelets displayed markedly superior structural and functional integrity at microgravity. Granulocytes held on the ground were preserved slightly better than those that orbited in the shuttle, whereas red cells displayed few effects that were attributable to the gravitational variable. Polyvinylchloride-di-(2-ethylhexyl)phthalate (PVC-DEHP) was the plastic of choice for storage of red cells, while PVC-trioctyltrimellitate (TOTM) was superior to PVC-DEHP and polyolefin (PO) for platelets. 相似文献
683.
重点中学中学生6 307人的抑郁障碍现况调查 总被引:2,自引:0,他引:2
目的了解中学生抑郁障碍的患病情况.方法在北京、辽宁、安徽3省市各随机取1所重点中学,在同1个月内分别对该校全体非毕业班的在校中学生6 307人采用抑郁自评量表进行抑郁障碍的筛查.对筛查结果异常及由班主任提供的筛查结果虽正常但怀疑有情绪问题的学生进行精神科检查,根据ICD-10中F32抑郁发作、抑郁复发和F34.1恶劣心境的诊断标准筛选出抑郁障碍的学生.其中北京市某校参加学生(北京组)3 727人;辽宁省某校学生(辽宁组)1 637人;安徽省某校高一年级学生943人(安徽组).结果发放问卷6 307份,收回合格问卷6 307份,有效率100%.①在6 307人,抑郁自评量表筛查的阳性率为23.50%;诊断为抑郁障碍的学生184例,患病率2.92%(184/6 307).其中北京组89例,辽宁组45例,安徽组50例.男女学生抑郁障碍的发病情况接近,差异无显著性意义(85/3 016,99/3 291,x2=0.392,P=0.531).三所中学高一学生的总检出率以安徽最高(50/943),辽宁次之(32/870),北京最低(25/668),差异无显著性意义(x2=5.423,P=0.066).北京组高中学生抑郁障碍患病率与辽宁组接近,差异无显著性意义[3.11%(42/1349),2.75%(45/1647),x2=0.344,P=0.558].②北京组中学学生抑郁障碍的总患病率为2.39%.初一学生的总患病率明显低于初二、高一、高二学生,且差异有显著性意义(P=0.001,0.011,0.037).但各年级中学生抑郁障碍男女性别之间差异均无显著性.③辽宁组中学学生抑郁障碍总检出率为2.75%.高一学生抑郁障碍患病率明显高于高二学生(3.68%,1.84%,x2=6.016,P=0.0146);各年级男女学生抑郁障碍患病率差异无显著性.④安徽组高一学生抑郁障碍总患病率为5.31%(50/943),男女学生差异无显著性意义(5.20%,5.44%,x2=0.027,P=0.870).结论所调查的重点中学学生中抑郁障碍比较常见,从初二年级开始出现有较明显的增加趋势,男女学生抑郁障碍的患病情况无明显差别. 相似文献
684.
SE Rogers ; D Edmondson ; MJ Goodrick ; GR Standen ; V Franck ; A Reppucci ; DH Pamphilon 《Transfusion》1995,35(9):727-733
BACKGROUND : Prestorage white cell (WBC) reduction in blood components may decrease the incidence of adverse reactions and improve component quality. A bottom-and-top system with an integral third-generation WBC- reduction filter has been studied. STUDY DESIGN AND METHODS : Whole blood was collected from 30 healthy donors: from 20 by using a blood container system with an integral filter and from 10 controls by using a standard blood container system. Ten test units were buffy coat- depleted, stored for 72 hours at 4 degrees C, and then filtered, while an additional 10 test units were buffy coat-depleted and filtered at room temperature within 8 hours of collection. All units were stored at 4 degrees C for 42 days and sampled weekly. RESULTS : The mean WBC content of the 72-hour, 4 degrees C units was 0.33 × 10(6), that of the room-temperature units was 2.6 × 10(6), and that of the buffy coat- depleted controls was 460 × 10(6) (p < 0.0005). No significant differences were found among lactate, glucose, sodium, potassium, and plasma hemoglobin levels in the three groups. ATP and 2,3 DPG levels were significantly better preserved in control units than in 72-hour, 4 degrees C units (p = 0.016 and p = 0.032, respectively), but not better than in the room-temperature units. Significant differences were observed between pH values in filtered units and both groups of test units (p = 0.016). In biologic terms however, these differences were small. Red cells from an additional eight healthy volunteer donors were processed by an 8-hour room-temperature method and stored for 35 days. Studies in vivo 24-hour recovery of autologous red cells were performed by transfusing a radiolabeled (51Cr plus 131I-albumin) aliquot after 35 days' storage. Good recovery (mean > 80%) was found by both the single- and double-isotope-label methods. Recovery was significantly greater when calculated by the single-isotope method (p = 0.02). CONCLUSION : The combination of buffy coat removal and filtration in the blood container system with an integral filter achieved effective WBC reduction (> or = 3 log10 reduction from whole blood) without biologically significant detriment to in vitro or in vivo storage values. 相似文献
685.
EL Blundell ; DH Pamphilon ; ID Fraser ; JE Menitove ; TJ Greenwalt ; EL Snyder ; AJ Repucci ; SL Hedberg ; JK Anderson ; DH Buchholz ; LR Kagen ; RH Aster 《Transfusion》1996,36(4):296-302
BACKGROUND: Irradiation of platelet concentrates (PCs) with ultraviolet- B (UVB) light inactivates the contaminating white cells and might be an alternative to filtration for the prevention of alloimmunization to HLA antigens and subsequent refractoriness to further platelet transfusions in multiply transfused patients with bone marrow failure. STUDY DESIGN AND METHODS: Patients with hematologic malignancy, mainly acute myeloid leukemia, were prospectively assigned in a random manner to receive either UVB-irradiated or control, nonirradiated PCs. All patients were given red cells that were white cell reduced by filtration. Transfusion efficacy and alloimmunization were assessed by means of corrected count increments, requirement for red cells and PCs, and measurement of lymphocyte-reactive antibodies. RESULTS: UVB-irradiated PCs had a clinical efficacy similar to controls as judged by corrected count increments at 1 to 6 and 12 to 24 hours and by the median requirement for red cell and platelet transfusions. Alloimmunization determined by measurements of lymphocyte-reactive antibodies using both conventional and antiglobulin-augmented lymphocytotoxicity techniques was not abolished in recipients of UVB-irradiated PCs (4/30, 13%) but was less than that in controls (5/20, 25%; p = NS). The mean number of platelet transfusion episodes prior to the occurrence of alloimmunization was greater in the control group (27 vs. 10; p = 0.017). CONCLUSION: In this trial, UVB irradiation did not diminish the clinical efficacy of platelet transfusions. There was a small but nonsignificant reduction alloimmunization, but no difference in refractoriness of the two groups was observed. Larger prospective randomized studies are required to confirm these findings and to compare UVB irradiation with white cell reduction. 相似文献
686.
DH Buchholz ; JP AuBuchon ; EL Snyder ; R Kandler ; V Piscitelli ; C Pickard ; P Napychank ; S Edberg 《Transfusion》1994,34(10):852-857
BACKGROUND: While prestorage white cell (WBC) reduction by filtration may improve platelet and red cell quality, it also may remove an important anti-bacterial defense mechanism, especially if blood is WBC- reduced shortly after collection. STUDY DESIGN AND METHODS: The question of whether WBC reduction of platelet concentrates and red cells altered bacterial proliferation kinetics in components prepared from deliberately contaminated, freshly collected blood was investigated. Two-unit pools of whole blood were inoculated, at a concentration of approximately one colony-forming unit per mL, with one of 17 bacterial species reported to have caused septicemia in transfusion recipients. Each pool was divided after inoculation, and components were prepared from the 2 units after a 7-hour room- temperature holding period. One unit of each AS-1 red cell or platelet pair was WBC-reduced, and the pairs were then stored for 42 days at 4 degrees C (red cells) or for 10 days at 22 degrees C (platelets). Quantitative bacterial cultures were performed at periodic intervals. RESULTS: In red cells, clinically significant bacterial proliferation occurred in only one instance (Serratia marcescens), and growth was less rapid in the WBC-reduced unit than in the control. Three patterns of growth were seen in platelet concentrates. In four cases, there was rapid proliferation in both test and control units, while on 13 occasions there was minimal replication in either pair. On six occasions, substantial growth was noted in control units, while few or no bacteria could be found in the WBC-reduced units. There was no evidence in either red cells or platelets that bacteria proliferated more rapidly in units that had been WBC-reduced before storage than they did in units in which WBCs were retained. CONCLUSION: Rather than increasing the risk of bacterial proliferation through removal of active phagocytic cells, WBC reduction by filtration before blood storage may act to reduce the likelihood of significant bacterial proliferation, possibly by removal of microorganisms along with WBCs. 相似文献
687.
Forty patients with advanced hematologic malignancies or severe aplastic anemia received marrow grafts from partially mismatched, unrelated marrow donors. All patients were administered conventional prophylaxis for acute graft-v-host disease (GVHD) consisting of methotrexate and low-dose glucocorticoids. All but two patients who survived at least 30 days showed durable engraftment. Six patients survive 17+ to 36+ months following transplantation. Severe acute GVHD was seen in 47% of the patients; however, no direct correlation between GVHD and the degree of mismatching could be determined. Fatal infections were seen in 29 patients, and in the majority the infection occurred after the granulocyte count had risen to greater than 500 cells/microL. We conclude that the problems encountered in this pilot study can potentially be solved, and that further studies with this type of marrow grafting are warranted. 相似文献
688.
Nonrandom inactivation of the X chromosome in early lineage hematopoietic cells in carriers of Wiskott-Aldrich syndrome 总被引:5,自引:7,他引:5
The Wiskott-Aldrich syndrome (WAS) is an X-linked (Xp11.22) recessive immunodeficiency syndrome characterized by susceptibility to opportunistic and pyogenic infections, thrombocytopenia, and eczema. Previous studies of obligate carriers of WAS documented that nonrandom inactivation of the X chromosome carrying the defective gene is observed in all peripheral blood cells. The existence of both abnormal platelets and lymphocytes is consistent with a defect that affects early hematopoietic precursors. We isolated CD34+ hematopoietic progenitor cells collected from obligate carriers of WAS by apheresis and used polymerase chain reaction analysis of a polymorphic variable number of repeats (VNTR) within the X-linked androgen receptor to document nonrandom inactivation. These data show that nonrandom inactivation of the X-chromosome in WAS-obligate carriers occurs early during hematopoietic differentiation. 相似文献
689.
Schattner EJ; Mascarenhas J; Bishop J; Yoo DH; Chadburn A; Crow MK; Friedman SM 《Blood》1996,88(4):1375-1382
Cytotoxic function of CD4+ Th1 cells is mediated by Fas (CD95, APO-1) and its ligand (Fas ligand). Recent studies using nontransformed B cells and the Ramos Burkitt's lymphoma (BL) B-cell line cells show that CD40 ligation at the B-cell surface by activated, CD40 ligand (CD40L)- bearing, CD4+ T cells upregulates Fas expression on B cells and primes B cells for Fas-mediated death signals. In this work, we examine whether this CD4+ T-cell-dependent molecular pathway for Fas upregulation and B-cell apoptosis reflects a peculiarity of the Ramos B- cell line or is applicable to other Burkitt's tumors as well. In 5 of the 6 Epstein-Barr virus-negative BL cell lines examined, the cells constitutively express undetectable or low levels of Fas and are resistant to Fas-mediated signals induced by monoclonal anti-Fas antibody. All 6 of the BL cell line B cells upregulate Fas in response to CD40 ligation, and in 4 of the cases they become sensitive to Fas- mediated death signals. In one BL cell line, the cells are constitutively sensitive to Fas-mediated cytolysis and are unaffected by CD40 signals. Next, we applied these immunologic manipulations to cells from a refractory clinical sample and observed that the tumor cells could be induced to express Fas and undergo apoptosis in our system. These results establish CD4+ T cells and the Fas-Fas ligand system as important immune regulators of Burkitt's lymphoma B cells and indicate that the susceptibility of tumor cells to Fas-mediated death signals can be modulated by specific activation events at the cell surface. 相似文献
690.
Expression of embryonic zeta-globin and epsilon-globin chains in a 10- year-old girl with congenital anemia 总被引:1,自引:0,他引:1
A 10-year-old Danish girl with congenital anemia is described. At birth, she had severe anemia and erythroblastosis and was transfused a number of times during the first year. The need for transfusions has since declined steadily. Her reticulocyte counts varied between 2% and 15%, and her bone marrow aspirate showed some dyserythropoietic features. Her hemoglobin F level was consistently elevated, up to as much as 41%. Her erythrocytes had a normal level of I antigen but an undetectable level of i antigen. Moreover, embryonic zeta-globin and epsilon-globin chains were present in some of her circulating erythrocytes. These findings may represent the manifestations of a new variant of congenital anemia. 相似文献