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采用超临界流体色谱法(SFC)分别测定了不同产地的怀牛膝药材及三种含怀牛膝的制剂中齐墩果酸的含量。方法简单、快速。不需经特殊的纯化处理。各产地药材齐墩果酸含量波动较小(1.75~2.19%,x±SD=1.94±0.17%),可以作为药材与制剂质量评价的指标,药材的加样回收率为97.42%(n=18,RSD=2.80%);制剂天麻丸的加样回收率为94.82%(n=9,RSD=2.51%)。  相似文献   
84.
BACKGROUND: Target organs express antigens recognized directly by antigen-specific T cells, and their recognition is crucial to precipitate rejection. Then, the earliest T-cell activation is inhibited by cyclosporine A (CsA), the lowest would be the risk of rejection. Here, we aimed to assess this possibility in a large cohort of de novo kidney transplant recipients participating in an ongoing clinical trial, the Mycophenolate Steroid-Sparing (MY.S.S.) Trial. METHODS: Three-hundred-thirty-four patients entered the prospective, multicenter MY.S.S. trial. The main aim of the study was to assess the predictive value of serial evaluation of blood CsA trough concentration (C0) and 2-hour postdose drug (C2) levels alone or in combination, and to identify which is the critical posttransplant measurement to target CsA therapy in order to minimize the risk of acute rejection. A very large number of CsA trough (N= 2236) and C2 (N= 2128) measurements during the first 6 months postsurgery were available for analysis. Patients with delayed graft function were excluded. RESULTS: CsA trough levels measured at day 2 posttransplant were the strongest predictor of acute graft rejection over 6-month follow-up. Levels within 300 to 440 ng/mL were associated with the lowest risk of rejection, while for levels lower than 300 ng/mL, the risk of acute rejection was more than doubled. Higher levels failed to provide any further protection from graft rejection. CsA trough values predicted allograft rejection with an accuracy of 74%, while C2 levels considered alone had no predictive values at all. CONCLUSION: Findings that among serial daily measurements posttransplant those taken as early as at day 2 have by far the highest capacity to predict rejection episodes, underline the need of targeting CsA therapy very early posttransplant with the goal to modulate early enough T-cell activation at the interface between the recipient's blood and the graft where alloimmune response actually initiates.  相似文献   
85.
目的:观察胶质细胞源性神经营养因子与转化生长因子β1体外联合诱导对脊髓源性神经干细胞分化的影响,为了解神经干细胞在体内多因素环境下的分化表现提供实验依据。方法:实验于2005-10/2006-09在南方医科大学附属深圳医院中心实验室完成。①碱性成纤维细胞生长因子,表皮生长因子,胶质细胞源性神经营养因子,转化生长因子β1(PeproTech);胎牛血清(Hyclone);神经巢蛋白多抗(武汉博士德);胶质纤维酸性蛋白多抗,神经丝蛋白单抗(Sigma)。②选用清洁级孕16d的SD大鼠10只,无菌条件下取出胚胎,进行脊髓源性神经干细胞的分离培养。基础培养基组成:含青霉素、链霉素、两性霉素B及体积分数为0.02B27添加液的DMEM/F12。③原代培养1周后,获取体外稳定增殖的鼠脊髓源性神经干细胞克隆,在基础培养基中加入体积分数为0.1的胎牛血清作为对照。同时设立碱性成纤维细胞生长因子组、转化生长因子β1组、胶质细胞源性神经营养因子 转化生长因子β1组,换用诱导培养基,即分别在基础培养基中加入20μg/L碱性成纤维细胞生长因子、2μg/L转化生长因子β1、10μg/L胶质细胞源性神经营养因子 2μg/L转化生长因子β1。观察在不同因子诱导情况下脊髓源性神经干细胞的分化行为,免疫细胞化学染色标记神经元与星状胶质细胞的表达。④通过荧光激发流式细胞仪分选技术对分化细胞计数,检测不同诱导环境下神经干细胞分化为神经元及星状胶质细胞的阳性百分率。结果:①细胞分化的形态学观察:分化早期可见神经球贴壁,大量细胞向四周爬出,1周后迁徙的大部分细胞完全贴壁,完成分化过程。在细胞密度较低区域可辨认出3种神经细胞类型:神经元样细胞、星状胶质样细胞、寡突胶质样细胞。②神经干细胞免疫组织化学检测:血清对照组、转化生长因子β1组存在大量胶质纤维酸性蛋白染色阳性的星状胶质细胞;而碱性成纤维细胞生长因子组、胶质细胞源性神经营养因子 转化生长因子β1组分化的神经元细胞数量较多,神经丝蛋白染色阳性。③流式细胞荧光分选计数:诱导1周后,胶质细胞源性神经营养因子 转化生长因子β1组神经元分化比例最高,明显高于碱性成纤维细胞生长因子组(χ2=19.56,P<0.05),而与血清对照组、转化生长因子β1组比较差异有极其显著性意义(χ2=24.15,25.32,P均<0.01)。碱性成纤维细胞生长因子组星状胶质细胞分化比例最低,胶质细胞源性神经营养因子 转化生长因子β1组组与其相近(χ2=17.23,P>0.05),而血清对照组、转化生长因子β1组则显著升高(χ2=24.45,23.79,P均<0.01)。结论:体外胶质细胞源性神经营养因子与转化生长因子β1的联合诱导有利于脊髓源性神经干细胞向神经元的分化,为脊髓原位神经干细胞分化及神经干细胞移植体内后的分化表现提供了实验数据。  相似文献   
86.
目的通过在结肠镜检查中给患者看DVD,了解视觉分散和视听联合分散对受检者焦虑和接受性的影响。方法采用随机对照的研究方法,将180例准备行结肠镜检查的患者随机分为三组,每组60例,视觉分散组检查时看DVD但不听DVD里播放的声音,视听分散组检查时看DVD并戴着耳机听DVD里播放的声音,对照组检查时不看DVD,比较三组患者间的焦虑水平和接受性。结果视觉分散组和视听分散组检查后焦虑水平降低较对照组显著,但这种差异未达到统计学意义。视觉分散组和视听分散组的愿再检查率均较对照组高(P<0.05)。结论视觉分散和视听分散能增加结肠镜检查患者的接受性,对患者的焦虑水平无显著影响。  相似文献   
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88.
A questionnaire was sent to all doctors working in emergency departments in Hong Kong to survey their attitudes and beliefs towards domestic violence. Beliefs concerning privacy and traditional cultural values were found to be important factors affecting the doctor's ability to identify cases of wife abuse. Most respondents had no formal training in this area and felt inadequate in the handling of domestic violence cases. Ways to improve training and identification of at risk cases are discussed.  相似文献   
89.
EJ Read  ; LL Cardine  ; MY Yu 《Transfusion》1991,31(6):502-508
In vivo survival studies of human red cells (RBCs) are commonly carried out by using chromium-51 (51Cr), a gamma-emitting radionuclide, as the cell label. The effects of labeling human RBCs with PKH-2, a nonradioactive lipophilic fluorescent dye that binds to the cell membrane, and the feasibility of detecting the labeled cells by flow cytometric analysis were investigated. Optimal labeling, defined as maximum mean fluorescence intensity with minimal cell-to-cell variability in fluorescence intensity and minimal cell loss, was achieved with the use of 15.0 x 10(-6) M (15.0 x 10(-6) mol/L) PKH-2 and a cell concentration of 4.0 x 10(9) RBCs per mL. Both freshly drawn and stored RBCs could be labeled, but RBCs stored for more than 20 days did not take up the label as uniformly as fresher cells. Although labeling with PKH-2 did not interfere with the detection of ABO, Rh(D), or common minor RBC antigens by routine serologic methods, it resulted in a morphologic appearance resembling echinocytosis and an increased resistance to osmotic lysis by hypotonic saline. RBCs labeled by this method could be quantitated accurately in blood samples in which their proportion was 0.01 percent, or 1 labeled cell in 10,000 cells. This method holds promise as a simple, reliable, and sensitive method for the detection of labeled human RBCs, but the in vivo significance of the label's effects on cell morphology and osmotic fragility is not known. Further studies directly comparing PKH-2-labeled and 51Cr-labeled RBCs will be necessary to establish the accuracy of the former method in determining the in vivo survival of human RBCs.  相似文献   
90.
The occurrence of calcific myonecrosis of the anterior compartment of the leg is rare. Common risk factors include a history of trauma, although little is known about the exact pathophysiology, latency period or triggering factors resulting in disease progression. Macroscopically, it begins with a single muscle being replaced by a fusiform calcified mass, which progresses peripherally. We present a rare case of a 7‐year history of chronic discharging sinus overlying the site with protruding calcified muscle and discuss the senior author's wound management strategy and surgical considerations. The initial approach used dressing applications to reduce wound exudate while obtaining repeated imaging for disease progression comparison. Repeated CT scans showed significant disease progression from a single solitary amorphous soft tissue calcification to disseminated scattered calcified myonecrosis. In planning such surgeries, extensive debridement and temporary wound coverage is the first stage. Subsequent definitive coverage includes skin grafting of the remaining defect.  相似文献   
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