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21.
A near-fatal reaction during granulocyte transfusion of a neonate   总被引:1,自引:0,他引:1  
Although reactions to granulocyte transfusions in neonates are rarely reported, we observed a near-fatal pulmonary reaction, presumably due to white cell antibodies, in a neonate with Rh hemolytic disease. The hemolytic disease was being treated with exchange transfusions, and at 2 days after the infant's birth, bacterial sepsis was suspected and granulocyte transfusions were begun. The first granulocyte transfusion (Day 3) was uneventful. Five minutes after the beginning of the second granulocyte transfusion (Day 4), severe respiratory distress, hypotension, bradycardia, cyanosis, and acidosis suddenly occurred. The infant's serum obtained after the reaction contained granulocytotoxic and B-lymphocytotoxic antibodies that reacted with leukocytes from the second granulocyte donor. Antibodies could not be detected either in the initial infant serum or in maternal serum. However, an antileukocyte antibody was present in the serum of a parous woman donor. We used plasma from this woman to prepare reconstituted whole blood for the exchange transfusion that we performed immediately preceding the second granulocyte transfusion. Despite the sequence of events, an irrefutable cause-and-effect mechanism could not be established because the properties of the donor and neonatal antibodies were similar, but not identical. However, this catastrophic event emphasizes both the potential for adverse effects of granulocyte transfusions in neonates and the need for caution when transfusing blood from parous women.  相似文献   
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Recombinant human (rh) interleukin-3 (IL-3) stimulated the proliferation and differentiation of erythroid, granulocyte, macrophage, eosinophil (Eo), and mixed colonies as well as megakaryocytes from human bone marrow cells. rh IL-3 was a weaker stimulus than rh granulocyte-macrophage colony-stimulating factor (GM- CSF) for day 14 myeloid cell colonies. At day 7 of incubation, rh IL-3 stimulated a few G, M, and Eo clusters but no colonies. This loss of responsiveness of myeloid cells to rh IL-3 was accentuated with further differentiation of the cells. rh IL-3 stimulated very few or no clones after five-day incubation with enriched promyelocytes and myelocytes, whereas rh GM-CSF was an efficient stimulus. Responsiveness to rh IL-3 was completely lost in postmitotic mature neutrophils. Incubation of these cells with rh IL-3 did not result in enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) of tumor cells or superoxide anion production after stimulation with formyl-methyl-leucyl-phenylalanine (FMLP), although they could be stimulated by rh GM-CSF. In addition, preincubation of neutrophils with different concentrations of rh IL-3 failed to increase or decrease their response to rh GM-CSF. In contrast to neutrophils, mature Eos could be stimulated by rh IL-3 to kill antibody-coated tumor cells. These results show that cells of the neutrophilic myeloid series lose their responsiveness to h IL-3 as they differentiate and suggest that although h IL-3 may be an important therapeutic agent to use for hematopoietic regeneration in vivo, the lack of stimulation of mature neutrophil function makes it an unlikely sole candidate as adjunct therapy for treatment of infectious diseases.  相似文献   
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BACKGROUND: The purpose of this study was to evaluate the safety and efficacy of a temperature-controlled radiofrequency catheter ablation system. METHODS AND RESULTS: The patient population included 1050 patients who had undergone ablation of atrioventricular nodal reentrant tachycardia (AVNRT), an accessory pathway (AP), or the atrioventricular junction (AVJ). Ablation was successful in 996 patients. The probability of success was highest among patients who had undergone ablation of the AVJ, lowest in patients who had undergone ablation of an AP, and in between for patients who had undergone ablation of AVNRT. A major complication occurred in 32 patients. Four variables predicted ablation success (AVJ, AVNRT, or left free wall AP ablation and an experienced center). Four factors predicted arrhythmia recurrence (right free wall, posteroseptal, septal, and multiple APs). Two variables predicted development of a complication (structural heart disease and the presence of multiple targets), and 3 variables predicted an increased risk of death (heart disease, lower ejection fraction, and AVJ ablation). CONCLUSIONS: These findings may serve as a guide to clinicians considering therapeutic options in patients who are candidates for ablation.  相似文献   
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目的 研究卡马西平(CBZ)的诱变性及其与叶酸的关系,探讨CBZ致畸及叶酸防止致畸的机制。方法 应用细胞遗传学方法,检测15例单服CBZ及15例CBZ加叶酸的癫痫患者外周血淋巴细胞染色体畸变率(CAR)、姐妹染色单体交换(SCE)频率,同时用放免法测定血清叶酸含量,并与未服药癫痫对照组及正常对照组进行比较。结果 单服CBZ组患者的CAR和SCE频率较对照组增高,其血清叶酸含量较正常对照组下降;单服CBZ组患者的CAR和SCE频率较服CBZ加叶酸组增高;CBZ血药浓度与叶酸水平CAR及SCE之间未发现明显相关性。结论 CBZ具有DNA损伤效应,其损伤效应可能与CBZ干扰叶酸代谢有关,补充叶酸可以有效防止CBZ引起的DNA损伤。  相似文献   
27.
胸腺瘤临床病理的预后因素研究   总被引:6,自引:2,他引:6  
目的 探讨胸腺瘤临床病理特点与预后的关系。方法 对130例胸腺瘤的重症肌无力、肿瘤大小、坏死、核分裂及包膜情况、组织学分型(按照L-B分类及M-H分类)、Massaoka临床分期等诸多因素进行分析,观察其5,10年生存率的差别,所得数据进行统计学U检验及χ^2检验。结果 重症肌无力的有无、肿瘤大小、坏死、核分裂及L-B分类均与预后无关(P>0.05);而肿瘤有无包膜、M-H分类及临床分期与生存率有明显相关性。有包膜者5,10年生存率分别为100%和93.1%,无包膜者分别为54.4%和40.0%(P<0.05)。按M-H分类,髓质型5,10年生存生存率分别为100%和79.8%,混合型分别为97.5%和88.4%,皮质为主型分别为83.3%和50.1%,皮质型分别为60.2%和29.9%,分化好的胸腺癌(WDTC)分别为43.4%和0%(P<0.05)。临床分期中Ⅰ期5,10年生存率分别为100%和93.2%,Ⅱ期分别为84.6%和78.4%,Ⅲ期分别为45.3%和19.8%,Ⅳ期分别为38.0%和0(P<0.01)。其中以细胞的异型性及有无侵犯胸腺周围器官对预后尤为重要。结论 L-B分类与预后无关;M-H分类、临床分期与预后有关,尤其是瘤细胞呈多角形和大圆形、临床侵犯胸腺外器官者对预后影响较明显。  相似文献   
28.
One of the most serious problems with endothelial cell (EC) seeding of prosthetic materials is the poor adhesion and stability of the cells. Although several substrates that improve the initial adhesion have been assayed, the EC are lost within a limited period of time. In this study we attempted to modify the hydrophobic conditions of expanded polytetrafluoroethylene (ePTFE) by treating it with ethanol prior to seeding. In addition, we created a fibroblastic matrix that was also fixed by ethanol to the prosthetic material. In vitro studies were carried out at intervals of 24 hours and 15 days after seeding. EC from umbilical cord vein and fibroblasts from skin were seeded onto disks of PTFE with a porosity of 30 µm. The results obtained show that treatment of ePTFE with ethanol prior to EC seeding modifies its permeability, preventing cellular adhesion. The seeding of fibroblasts onto ePTFE allows a coating to form at 24 hours. The EC seeded onto this matrix adhere to it, forming a monolayer that persisted throughout the entire study period. The fibroblastic matrix allows the long-term survival of the EC on ePTFE.Supported by a grant from the CICYT SAF 92-0875.  相似文献   
29.
柴胡皂甙q及其甙元的结构鉴定   总被引:4,自引:0,他引:4  
从小叶黑柴胡(Bupleurum smithii Wolffvar;parvifolium ShanetY.Li)的根中得到3个化合物,柴胡皂甙元A和Q及柴胡皂甙q。柴胡皂甙元Q和柴胡皂甙q为新化合物,根据理化性质和波谱分析,确定其结构分别为齐墩果烷-11,13(18)-二烯-3β,16β,23,28,30-五醇和3β,16β,23,28,3O-五羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基(1→6)-[α-L-吡喃鼠李糖基(1→4)]-β-D-吡喃葡萄糖甙。  相似文献   
30.
Objective:  Hutchinson-Gilford progeria syndrome (HGPS) is a rare early-onset accelerated senescence syndrome. In HGPS, a recently identified de novo dominant mutation of the lamin A gene ( LMNA ) produces abnormal lamin A, resulting in compromised nuclear membrane integrity. Clinical features include sclerotic skin, cardiovascular and bone abnormalities, and marked growth retardation. Craniofacial features include 'bird-like' facies, alopecia, craniofacial disproportion, and dental crowding. Our prospective study describes dental, oral soft tissue, and craniofacial bone features in HGPS.
Methods:  Fifteen patients with confirmed p.G608G LMNA mutation (1–17 years, seven males, eight females) received comprehensive oral evaluations. Anomalies of oral soft tissue, gnathic bones, and dentition were identified.
Results:  Radiographic findings included hypodontia ( n  = 7), dysmorphic teeth ( n  = 5), steep mandibular angles ( n  = 11), and thin basal bone ( n  = 11). Soft tissue findings included ogival palatal arch ( n  = 8), median sagittal palatal fissure ( n  = 7), and ankyloglossia ( n  = 7). Calculated dental ages (9 months to 11 years 2 months) were significantly lower than chronological ages (1 year 6 months to 17 years 8 months) ( P  = 0.002). Eleven children manifested a shorter mandibular body, anterior/posterior cranial base and ramus, but a larger gonial angle, compared to age/gender/race norms.
Conclusion:  Novel oral-craniofacial phenotypes and quantification of previously reported features are presented. Our findings expand the HGPS phenotype and provide additional insight into the complex pathogenesis of HGPS.  相似文献   
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