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771.
人类项韧带的精细解剖结构   总被引:1,自引:0,他引:1  
目的:观察人类项韧带的精细解剖结构及形态。方法:实验于2004-09/2005-04在大连医科大学解剖教研室及大连医大生物塑化有限公司科研部完成。观察对象为4具成人尸体的颈部,均有完整的颈部(椎)全段,包括颅骨后枕外隆突。其中1具尸体进行肉眼大体解剖;3具尸体取寰椎到C7水平,制作成P45(聚酯树脂)生物塑化薄片。所有标本及材料均由大连医大生物塑化有限公司及大连医科大学解剖教研室提供。观察大体标本及P45断层塑化薄片标本,记录各种新发现。最后将两部分的观察及影像结果合并,利用断层解剖知识,标注项韧带组织名称并进行分析。结果:在颈椎的不同平面,项韧带的浅层、背侧部和腹侧部分别由斜方肌、头夹肌、小(大)菱形肌和上后锯肌的腱膜纤维组成的一个整体,且绝大部分纤维走向为横行。结论:①项韧带的结缔组织纤维不是全部纵向走行的,是以横向走行为主的肌腱腱膜组织纤维。②P45生物塑化薄片技术的应用使项韧带精细解剖结构的全貌更直观。  相似文献   
772.
感染性休克病人的血流动力学特点及意义   总被引:6,自引:4,他引:6  
目的 了解感染性休克病人早期血流动力学改变的特点及预后关系。方法 临床前瞻性研究,监测感染性休克早期血流动力学改变并分析与预后的关系。结果 共连续观察48例病人,其中25例(52%)死亡。一些指标的水平在死亡者与生存者间差别较大,其中包括平均肺动脉压(MPAP)、肺动脉楔压(PAWP)、体/肺循环阻力指数(SVRI/PVRI)、左/右心做功(LCW/RCW)和左/右心每搏动(LCSW/RCSW)等血流动力学指标的氧合指数,动脉混合静脉血含氧量差(a-vDO2)、全身性为症反应综合征(SIRS)指标积分等。结论 感染性休克病情凶险,部分血流动力学指标对早期评估其预后有指标作用。  相似文献   
773.
Extensive immunologic marker analysis was performed to characterize the various leukemic cell populations in eight patients with inv(16)(p13q22) in association with acute myeloid leukemia with abnormal bone marrow eosinophilia (AML-M4Eo). The eight AML cases consisted of heterogeneous cell populations; mainly due to the presence of multiple subpopulations, which varied in size between the patients. However, the immunophenotype of these subpopulations was comparable, independent of their relative sizes. Virtually all AML-M4Eo cells were positive for the pan-myeloid marker CD13. In addition, the AML were partly positive for CD2, CD11b, CD11c, CD14, CD33, CD34, CD36, CDw65, terminal deoxynucleotidyl transferase (TdT), and HLA-DR. Double immunofluorescence stainings demonstrated coexpression of the CD2 antigen and myeloid markers and allowed the recognition of multiple AML subpopulations. The CD2 antigen was expressed by immature AML cells (CD34+, CD14-) and more mature monocytic AML cells (CD34-, CD14+), whereas TdT expression was exclusively found in the CD34+, CD14- cell population. The eight AML-M4Eo cases not only expressed the CD2 antigen, but also its ligand CD58 (leukocyte function antigen-3). Culturing of AML-M4Eo cell samples showed a high spontaneous proliferation in all three patients tested. Addition of a mixture of CD2 antibodies against the T11.1, T11.2, and T11.3 epitopes diminished cell proliferation in two patients with high CD2 expression, but no inhibitory effects were found in the third patient with low frequency and low density of CD2 expression. These results suggest that high expression of the CD2 molecule in AML-M4Eo stimulates proliferation of the leukemic cells, which might explain the high white blood cell count often found in this type of AML.  相似文献   
774.
Optimal prophylaxis of graft-versus-host disease (GVHD) is controversial. We compared efficacy of three posttransplant immune suppressive regimens in 2,286 recipients of HLA-identical sibling bone marrow transplants for acute lymphoblastic leukemia (ALL) in first remission, acute myelogenous leukemia (AML) in first remission, or chronic myelogenous leukemia (CML) in first chronic phase. Six hundred forty received methotrexate, 977 received cyclosporine, and 669 received combined cyclosporine and methotrexate. In children, the three regimens resulted in similar outcomes. In adults, cyclosporine and methotrexate had comparable risks of acute and chronic GVHD. Compared with methotrexate, cyclosporine was associated with less interstitial pneumonia (relative risk [RR] = 0.6; P < .001), less treatment-related mortality (RR = 0.6; P < .001), more relapses (RR = 1.6; P < .05), and less treatment failure (relapse or death from any cause; RR = 0.7; P < .001). Different effects were observed in different leukemias. In ALL, the rate of leukemia relapse was increased with cyclosporine versus methotrexate, with no effect on other outcomes. In AML and CML, interstitial pneumonia, treatment-related mortality, and treatment failures were decreased with cyclosporine, with no increase in relapse. Similar analyses comparing cyclosporine plus methotrexate with cyclosporine alone showed that adults receiving the combination had less acute GVHD (RR = 0.5; P < .001), less chronic GVHD (RR = 0.7; P < .01), and less interstitial pneumonia (RR = 0.7; P < .001). Treatment failure (RR = 0.8; P < .05) was marginally reduced. Separate analyses in ALL and AML showed less acute GVHD with combined therapy, but no significant effect on other outcomes. In CML, acute GVHD, interstitial pneumonia, treatment-related mortality, and treatment failure were decreased with combined therapy.  相似文献   
775.
The tropism of the human T-cell leukemia virus type 1 (HTLV-1) for the cells of monocyte-macrophage lineage was evaluated by the coculture of blood monocyte-derived macrophages, with irradiated cells of HTLV-1 producing cell lines MT2 or C91/PL. The susceptibility to HTLV-1 was assessed by the detection of viral DNA using the polymerase chain reaction method. HTLV-1 gene expression in the cells was detected using in situ hybridization and by immunofluorescent staining of viral antigen. The presence of type C virus-like particles detected by electron microscopy and the ability to infect normal cord blood lymphocytes demonstrated that the infected macrophages produced infectious virus. These results indicate that human macrophages are susceptible in vitro to productive HTLV-1 infection, and thus might be involved in the pathogenesis of HTLV-1-related diseases.  相似文献   
776.
Rana  SV; Reimers  HJ; Pathikonda  MS; Bajaj  SP 《Blood》1988,71(1):259-262
Previously, unstimulated cells of the human monocytic tumor cell line U937 have been shown to possess a negligible cell-surface tissue factor (TF) activity, and to secrete a small amount of factor VIIa/tissue factor (VIIa/TF) inhibitor activity. On stimulation with endotoxin or with phorbol myristate acetate (PMA), TF of these cells is known to be increased approximately fourfold. In this report, we demonstrate that VIIa/TF inhibitor is also increased on stimulation of U937 cells with endotoxin (approximately equal to threefold) or with PMA (approximately equal to 20-fold). Notably, the secretion of the inhibitor persisted after the cell surface TF had started to decline. Further, when serum- free media from PMA stimulated cells was electrophoresed on a sodium dodecyl sulfate (SDS) gel, we eluted two inhibitor activity peaks corresponding to Mr approximately equal to 47,000 and Mr approximately equal to 36,000. The molecular weights of these peaks are similar to those obtained earlier from human plasma for this inhibitor(s).  相似文献   
777.
We studied the effects of cis-retinoic acid (cisRA) on the clonogenic growth of samples of leukemic cells from 35 patients with acute nonlymphocytic leukemia (ANLL). We observed significant inhibition of leukemic colony growth in 17 samples by 10(-7) to 10(-6)M cisRA. However, we found that retinoid exposure resulted in striking stimulation of clonal growth in ten samples at the same drug concentrations. With the exception of cases with promyelocytic features, there was no morphologic or functional evidence that cisRA induced the leukemic blasts to differentiate. Both inhibition and stimulation were dose-dependent and observable at pharmacologically achievable levels of cisRA. Leukemic cells with monocytic features more frequently demonstrated a stimulatory response than did those without monocytic features. Depletion of T lymphocytes and monocytes did not alter the type of growth response. Assays for cellular retinoic acid- binding protein (CRABP) were performed on five samples (two with inhibitory growth responses, two with stimulatory responses, and one with no growth) and failed to reveal detectable levels of CRABP in any case. The addition of cisRA to liquid suspensions of leukemic cells produced no significant change in the number of viable cells. We conclude that the effects of cisRA on leukemic colony growth are not cytotoxic and not mediated by T lymphocytes, monocytes, or CRABP. More importantly, cisRA appears to enhance the growth of certain human leukemia cells in vitro. Taking into account the increasing use of retinoids in clinical trials for patients with leukemia, the latter findings may represent a significant cautionary note.  相似文献   
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779.
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