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苗慧  肖文彬  秦伯益 《药学学报》1990,25(9):646-651
本实验观察了MHDF对整体大鼠血流动力学和离体大鼠胸主动脉的作用。结果表明iv MHDF(3~12.8 mg/kg)能降低大鼠左心室±dp/dtmax,Vmax,Vpm和LVSP,延长T-dp/dtmax,减慢心率。MHDF还能舒张大鼠胸主动脉,ED50为6.5×10-6mol/L;非竞争拮抗NA和CaCl2致主脉收缩,pD2′为3.11±0.21和3.73±0.07;抑制高K+致主动脉收缩,IC50为1.76×10-5mol/L。提示MHDF对血管的作用与α受体阻断剂不同,而可能与钙拮抗有关。  相似文献   
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Morphometric analysis of thrombocytes from patients with Alzheimer's disease, from patients with multi-infarct dementia, and from young and agematched healthy control donors, did not reveal any Alzheimer-related increase in internal membranes. Biochemical analysis showed a reduced cholesterol content of thrombocyte membrane preparations from Alzheimer patients relative to age-matched controls, but not relative to multi-infarct dementia patients. Overall distribution of protein kinase C activity (PKC) between cytosol and membrane, in resting as well as in activated thrombocytes from Alzheimer patients, was similar to that in the control groups. However, both Alzheimer and multi-infarct dementia patients had lower cytosolic levels of basal kinase and PKC activities than age-matched controls, while only Alzheimer patients had lower cytoskeletal PKC activity than controls.  相似文献   
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0 引言为了克服离子选择电极(ISE)法的微量电位信号极易受环境温度变化及电子噪声的干扰问题,该仪器采用了参考电极,把参考电极与其测定电极装在同一测量室内,保持其相同的物理环境,使干扰源对所有电极的影响相同. 以内参液作为参考电极的测量对象,测得一个参考电极电位值,再测样品的电极电位值,二者相抵就消除了所叠加的干扰信号.  相似文献   
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心脏直视手术围术期自体血回输335例的监护   总被引:2,自引:0,他引:2  
0 引言 自体输血是采集患者体内血或回收自体失血,再输回同一患者,献血者与受血者为同一个体,既可以节约临床用血,减少患者费用,更重要是可以避免或减少同种输血传播感染性疾病.我科对335例体外循环心内直视手术患者实行自体血回输,收到较好的社会效益和经济效益.1 临床资料 1998-09/1999-02,我科心脏直视手术共445例,围术期采用自体输血335例,其中先心病226例,瓣膜手术59例,复杂心内畸形37例,冠心病、大血管13例,占同期体外循环心内直视手术75%.患者主要适应证:心脏及大血管外科手术,术前一般情况尚好,无肝、肾、呼吸功能障碍;术前检查…  相似文献   
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PURPOSE: To investigate potential immunotherapeutic strategies in B lymphocytic malignancies we looked for CTLs recognizing CD19 and CD20 epitopes. EXPERIMENTAL DESIGN: Three CD19 and CD20 peptides binding to HLA-A*0201 were identified and used to detect peptide specific CTLs by a quantitative real-time PCR to measure IFN-gamma mRNA expression in 23 healthy individuals and 28 patients (18 chronic lymphocytic leukemia (CLL), 7 follicular lymphoma, 2 acute lymphocytic leukemia, and 1 large cell lymphoma). Peptide-specific CTLs were expanded in culture with CD40-activated B cells to test lytic activity in three patients. RESULTS: In healthy individuals, CD8+ T-cell responses were detected in one to CD19(74-82), in three to CD20(127-135), and three to CD20(188-196). Seven of 27 patients (6 with CLL) had CD8+ T cells recognizing CD19(74-82). Seven patients responded to CD20(127-135) and three to CD20(188-196). All were CLL patients. CD19(74-82)-specific CTLs from three patients were expanded over 4 weeks. These cells were HLA-A*0201 specific and lytic for peptide-loaded antigen-presenting cells but not to malignant or unpulsed B cells. CONCLUSIONS: CTLs that recognize CD19 and CD20 epitopes exist in healthy individuals and may be increased in CLL patients. They are of low avidity and require high doses of peptide for activation. Strategies to increase T-cell avidity would be necessary for T-cell immunotherapeutic approaches using the peptides studied.  相似文献   
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Introduction:   Treatment of functional anorectal pain disorders remains a challenge. The purpose of this study is to describe a single center experience with sacral neuromodulation for the treatment of chronic functional anorectal pain.
Methods:   This is a retrospective study based on prospectively collected data of patients treated with sacral neuromodulation for functional anorectal pain from April 2005 to August 2008. Symptoms were analyzed using a visual analog scale pain score (0 to 10). A 7-point Likert scale was used to rate global perceived effect. All patients had a percutaneous nerve evaluation and subsequent test stimulation to assess sacral neuromodulation outcome prior to permanent implantation. Patients were eligible for permanent sacral neuromodulation in case of a pain score <3 during test stimulation and/or >50% decrease in the pain score compared to baseline.
Results:   Nine patients (2 males) were included in this study. Mean age was 53.8 years (27.6 to 74.0). Four patients (1 male) had successful test stimulation and were eligible for permanent implantation. Median pain score decreased from 8.0 (6.0 to 9.0) to 1.0 (0 to 2.0). All patients experienced a lasting improvement during the follow-up till 24 months. Global perceived effect in successful patient was 1 (completely recovered) in one patient and 2 (much improved) in three patients.
Conclusion:   This study showed that sacral neuromodulation can be a successful treatment for functional anorectal pain not responding to other treatments. Improvement obtained during test stimulation is a good predictor (diagnostic) for sustained success of permanent sacral neuromodulation.  相似文献   
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There is evidence that neutrophil production is a balance between the proliferative action of granulocyte-colony-stimulating factor (G-CSF) and a negative feedback from mature neutrophils (the chalone). Two neutrophil serine proteases have been implicated in granulopoietic regulation: pro-proteinase 3 inhibits granulocyte macrophage-colony-forming unit (CFU-GM) growth, and elastase mutations cause cyclic and congenital neutropenia. We further studied the action of the neutrophil serine proteases (proteinase 3, elastase, azurocidin, and cathepsin G) on granulopoiesis in vitro. Elastase inhibited CFU-GM in methylcellulose culture. In serum-free suspension cultures of CD34+ cells, elastase completely abrogated the proliferation induced by G-CSF but not that of GM-CSF or stem cell factor (SCF). The blocking effect of elastase was prevented by inhibition of its enzymatic activity with phenylmethylsulfonyl fluoride (PMSF) or heat treatment. When exposed to enzymatically active elastase, G-CSF, but not GM-CSF or SCF, was rapidly cleaved and rendered inactive. These results support a role for neutrophil elastase in providing negative feedback to granulopoiesis by direct antagonism of G-CSF.  相似文献   
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