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61.
This study of 52 European patients with Hodgkin's disease (HD) expressing the latent membrane protein 1 (LMP1) oncogene within diagnostic Hodgkin and Reed-Sternberg (HRS) cells was performed to detect LMP1 isolates carrying deletions and to characterize them at a molecular and histologic level. Deletions were identified in 5 cases, clustered near the 3' end of the LMP1 gene, and histologically associated with numerous HRS cells. DNA sequencing showed homology with the deletions seen in the Asian nasopharyngeal carcinoma (NPC) isolates CAO and 1510. Our findings suggest that partial deletions of the LMP1 oncogene, associated with aggressive behavior in NPC CAO and NPC 1510, occur at a particular localization and confer a proliferative phenotype to lymphoid cells in HD.  相似文献   
62.
本文设计,合成了2-(E)-取代苯亚甲基环戊酮(Ⅰ)类化合物18个及其Mannich碱盐酸盐(Ⅱ)类化合物11个,其中22个为新化合物。初步药理结果显示:对于角叉菜胶诱发的大鼠足趾水肿,Ⅰ_4,Ⅰ_(12)及Ⅰ_(13)口服有较显著的抑制作用,水溶性Ⅱ类化合物皮下注射有极强的抑制作用,其中Ⅱ_3于50,25和12.5 mg/kg剂量下抑制率分别为95.8%,70.3%和44.2%,它与布洛芬效力(25 mg/bg抑制率72.9%)相当.Ⅱ类化合物体外对L1210细胞及体内对荷艾氏腹水癌小鼠均有一定抗癌活性。  相似文献   
63.
To describe consumers' perceptions of genetic counseling services in the context of direct‐to‐consumer personal genomic testing is the purpose of this research. Utilizing data from the Scripps Genomic Health Initiative, we assessed direct‐to‐consumer genomic test consumers' utilization and perceptions of genetic counseling services. At long‐term follow‐up, approximately 14 months post‐testing, participants were asked to respond to several items gauging their interactions, if any, with a Navigenics genetic counselor, and their perceptions of those interactions. Out of 1325 individuals who completed long‐term follow‐up, 187 (14.1%) indicated that they had spoken with a genetic counselor. The most commonly given reason for not utilizing the counseling service was a lack of need due to the perception of already understanding one's results (55.6%). The most common reasons for utilizing the service included wanting to take advantage of a free service (43.9%) and wanting more information on risk calculations (42.2%). Among those who utilized the service, a large fraction reported that counseling improved their understanding of their results (54.5%) and genetics in general (43.9%). A relatively small proportion of participants utilized genetic counseling after direct‐to‐consumer personal genomic testing. Among those individuals who did utilize the service, however, a large fraction perceived it to be informative, and thus presumably beneficial.  相似文献   
64.

Purpose  

This research explores the sensitivity of three generic instruments for preference-weighting health states of family caregivers of children with craniofacial malformations (CFM). We also examine the construct validity of the new CarerQol instrument measuring caregiver burden and general quality of life.  相似文献   
65.
Mercury is known to cause harmful neural effects affecting the cardiovascular system. Here, we evaluated the chronic effects of low‐dose mercury exposure on the autonomic control of the cardiovascular system. Wistar rats were treated for 30 days with HgCl2 (1st dose 4.6 μg/kg followed by 0.07 μg/kg per day, intramuscular) or saline. The femoral artery and vein were then cannulated for evaluation of autonomic control of the hemodynamic function, which was evaluated in awake rats. The following tests were performed: baroreflex sensitivity, Von Bezold‐Jarisch reflex, heart rate variability (HRV) and pharmacological blockade with methylatropine and atenolol to test the autonomic tone of the heart. Exposure to HgCl2 for 30 days slightly increased the mean arterial pressure and heart rate (HR). There was a significant reduction in the baroreflex gain of animals exposed to HgCl2. Moreover, haemodynamic responses to the activation of the Von Bezold‐Jarisch reflex were also reduced. The changes in the spectral analysis of HRV suggested a shift in the sympathovagal balance toward a sympathetic predominance after mercury exposure, which was confirmed by autonomic pharmacological blockade in the HgCl2 group. This group also exhibited reduced intrinsic HR after the double block suggesting that the pacemaker activity of the sinus node was also affected. These findings suggested that the autonomic modulation of the heart was significantly altered by chronic mercury exposure, thus reinforcing that even at low concentrations such exposure might be associated with increased cardiovascular risk.  相似文献   
66.
Contrast enhancement in the postoperative brain   总被引:9,自引:0,他引:9  
  相似文献   
67.
BACKGROUND: There is intense interest in the potential of current white cell (WBC)-reduction filters to prevent the alloimmunization of patients by the residual donor WBCs in filtered blood components transfused to them. Little attention has been paid to the capacity of current synthetic fiber filters to remove WBC membrane fragments bearing detectable leukocyte antigens. STUDY DESIGN AND METHODS: Fluorescein isothiocyanate-conjugated monoclonal antibody to a universal WBC membrane antigen (CD45) and high-speed centrifugation coupled with ficoll-hypaque differential sedimentation were used to quantitate low-density WBC fragments in single-donor platelet components before and after filtration to determine if a polyester fiber filter retained WBC fragments. RESULTS: Prefiltration measurements in 25 single-donor platelet components indicated that WBC fragments increased with length of storage up to 5 days at room temperature (p < 0.0001). When fragments in eight components were measured before and after filtration, absolute values for differences were insignificant (p = 0.15). CONCLUSION: WBC fragments were poorly retained by these polyester fiber WBC-reduction filters. The antigenicity of WBC fragments could contribute to the WBC alloimmunization of some recipients of WBC-reduced blood components.  相似文献   
68.
Following our initial observation of in vivo conversion of CD7+, CD4-, CD8- acute lymphoblastic leukemia (ALL) cells from lymphoid to myeloid lineages (Proc Natl Acad Sci (USA) 81:253, 1984) we have studied eight additional cases of ALL with this leukemic cell phenotype. The CD7+, CD4-, CD8- phenotype was associated with a distinct clinical entity with those affected predominantly male (either less than 35 years or greater than 65 years of age), with frequent mediastinal and/or thymic masses, skin and CNS disease, high peripheral WBC counts, and bone marrow blasts that were morphologically L1 or not ascribable to a specific lineage. These patients did not respond to conventional chemotherapeutic regimens for either acute lymphoid or myeloid leukemias. No common karyotype or T-cell gene rearrangement pattern could be defined. Importantly, seven of eight patient's leukemic cells studied were capable of multilineage (myeloid, erythroid, monocytoid, megakaryocytoid, and lymphoid) differentiation in vitro. Data is presented suggesting that CD7+, CD4-, CD8- leukemias, in many instances, are leukemias of immature hematopoietic cells. The development of novel therapeutic approaches to this form of leukemia will be necessary to alter its poor prognosis.  相似文献   
69.
Levine  MN; Fay  JW; Jones  NH; Metzgar  RS; Haynes  BF 《Blood》1981,58(5):1047-1049
Cell surface antigens of the human bone marrow CFU-C have been studied. Human marrow cells were incubated with a variety of monoclonal antisera and complement prior to culture in semisolid media. By using indirect immunofluorescent studies, the percentage of bone marrow cells binding the antibodies was determined. The CFU-C phenotype is HLA+, la+, 4F2+, 3A1-, and DUALL-1-. This study provides information that is useful in the study of myeloid cell ontogeny and necessary for the use of some of these reagents in the treatment of bone marrow cells prior to human bone marrow transplantation in various clinical settings.  相似文献   
70.
目的:对胸腰椎压缩性骨折的复位目前主要是通过Harrington棒的撑开或Dick等器械压缩,间接地使压缩的椎体得到复位.但复位的力量不易掌握,效果往往也不够理想.因此,需要了解和掌握复位器未发生变形时所能承受的最大应力及椎体复位器在椎体内撑开复位的应力与位移的关系.方法:实验于1998-10/2003-04在上海市材料力学研究所、上海市第九人民医院生物力学研究室及上海第二医科大学解剖教研室市生物力学研究室完成.自行设计的椎体复位器为圆柱形,顶端的上下开启由尾端的圆形手柄控制.实验方法:①椎体复位器的抗压力实验:将椎体复位器撑开到最大后进行轴向压缩实验,当复位器刚好发生形变时的轴向压应力,即是复位器进行轴向撑开时所能承受最大应力.②新鲜小牛骨椎体抗轴向压力实验:在36个新鲜小牛骨椎体上制作压缩性骨折模型时,了解椎体形变时的应力形变的关系.实验前测出每个椎体的高度值,发生压缩形变后,再测量每个椎体的高度值,并在机器上测出相应的压应力值.③椎体复位器复位压缩性小牛骨椎体的生物力学实验:将20个新鲜小牛骨胸腰椎椎体分成2组,每组10个椎体.在轴向载荷下压缩椎体,制作压缩性骨折的模型,1/2椎体高度压缩组其压缩后高度接近原有椎体高度的1/2,2/3椎体高度压缩组其压缩后高度接近原有椎体高度的2/3.从椎体椎弓根两侧放入复位器,将压缩的椎体予以复位.了解复位器在椎体内的撑开应力与复位时位移关系.结果:①复位器未发生变形时所能承受的最大力为281 N.②36个新鲜小牛骨椎体在承受轴向载荷发生变形时屈服点的平均应力为74.96 kPa,各数据符合正态分布(t=16.044,P<0.01).③1/2椎体高度压缩组和2/3椎体高度压缩组复位器在椎体内撑开后应力值差异无显著性意义(t=0.835,P>0.05).结论:椎体压缩程度与椎体内撑开复位的力量没有直接关系,自行设计的椎体复位器在椎体内撑开复位的力量远小于复位器的屈服点应力.  相似文献   
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