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41.
Human red cells (RBCs) were collected in CPDA-1 and then freeze-dried in lyoprotective solution. The lyophilized RBCs were then stored at -20 degrees C for 7 days. At the end of the storage period, the lyophilized RBCs were rehydrated and washed in dextrose saline. The washed, reconstituted, lyophilized RBCs were resuspended in final wash solutions of ADSOL, CPDA-1, or a special additive solution containing glucose, citrate, phosphate, adenine, and mannitol, and then they were stored at 4 degrees C for an additional 7 days. The main purpose of this study was to determine whether human RBCs can be lyophilized in such a manner that normal metabolic, rheologic, and cellular properties are maintained during rehydration and subsequent storage in standard blood bank preservative solutions. Our results show that reconstituted, lyophilized RBCs maintained levels of ATP, 2,3 DPG, lactate, and cellular properties that are equal to or better than those in control nonlyophilized RBCs stored for a comparable period in CPDA-1. Reconstituted, lyophilized RBCs stored at 4 degrees C after rehydration also show better maintenance of ATP, 2,3 DPG, and lactate than do control RBCs stored in the same preservative solutions for comparable periods.  相似文献   
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Recent studies have demonstrated efficacy of immunotherapies including interleukin-2 (IL-2) in the treatment of malignancies in rodents and humans. High levels of IL-2 receptor-positive cells were found in the peripheral blood of patients receiving recombinant IL-2 in these Phase I clinical trials. This was demonstrated both in patients receiving i.v. IL-2 who had detectable circulating levels of IL-2 as well as in patients receiving i.p. IL-2 who did not. Up to 100% of the anti-Tac binding could be inhibited by preincubation with IL-2 indicating that this was indeed an IL-2 receptor that was identified. Two-color experiments demonstrated that few Leu 2-positive cells (less than 5-10%) but over 30% of the Leu 3-positive cells bore Tac antigen. Most of the M3-positive monocytes were Tac positive (83.7%) and negative for other T-cell (Leu-4) and nonspecific murine markers (Lyt-2 and Thy 1.2). Although normal individuals had a mean of only 186 units/ml (range, 83-335 units/ml) of soluble IL-2 receptor, patients receiving IL-2 had as much as 20,000 units/ml of soluble IL-2 receptor line in their serum. The physiological role of the IL-2 receptor identified on the cell surface of Leu 3 and M3-positive cells as well as in the serum is unclear. Soluble IL-2 receptors appeared in the circulation early following IL-2 administration, approximately 1 week prior to the detection of circulating IL-2 receptor-bearing cells. Further studies will be needed to assess the role of IL-2 in monocyte function, the precise function of IL-2 receptor-bearing Leu 3-positive cells, and the relationship of these findings to the toxicity and success of this immunotherapy in humans.  相似文献   
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目的:探讨敲低PI3Kp85α表达对人乳腺癌细胞系MCF-7细胞生长的影响和机制.方法:用靶向PI3Kp85α的siRNA转染人乳腺癌细胞系MCF-7,使用Real-time PCR法鉴定转染PI3Kp85α表达水平;MTT法评价PI3Kp85α siRNA对乳腺癌细胞系MCF-7生长的影响;流式细胞术检测转染后细胞周期分布和凋亡;采用免疫荧光染色及Western blot方法观察IA型PI3K/AKT通路主要成员的表达.结果:Real-timePCR结果显示PI3Kp85α siR-NA转染导致PI3Kp85α表达下调;MTT结果显示PI3Kp85α siRNA转染抑制肿瘤细胞生长;流式细胞术检测可见PI3Kp85α siRNA转染组细胞周期存在G_0/G_1期阻滞而且凋亡率显著高于对照组与空载体组(F=19.255,P=0.002).结论:应用PI3Kp85α siRNA转染人乳腺癌细胞系MCF-7细胞,可抑制其增殖和诱导细胞凋亡,因此PI3Kp85α可以作为人乳腺癌基因治疗的候选靶点.  相似文献   
45.
Adult T cell leukemia (ATL) and Sézary leukemia are malignant proliferations of T lymphocytes that share similar cell morphology and clinical features. ATL is associated with HTLV (human T cell leukemia/lymphoma virus), a unique human type C retrovirus, whereas most patients with the Sézary syndrome do not have antibodies to this virus. Leukemic cells of both groups were of the T3, T4-positive, T8-negative phenotype. Despite the similar phenotype, HTLV-negative Sézary leukemic cells frequently functioned as helper cells, whereas some HTLV-positive ATL and HTLV-positive Sézary cells appeared to function as suppressors of immunoglobulin synthesis. One can distinguish the HTLV-positive from the HTLV-negative leukemias using a monoclonal antibody (anti-Tac) that appears to identify the human receptor for T cell growth factor (TCGF). Resting normal T cells and most HTLV-negative Sézary cells were Tac-negative, whereas all ATL cell populations were Tac-positive. The observation that ATL cells manifest TCGF receptors suggests the possibility that an abnormality of the TCGF-TCGF receptor system may partially explain the uncontrolled growth of these cells.  相似文献   
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Culture and characterization of murine dendritic Thy-1+ epidermal cells   总被引:2,自引:0,他引:2  
Although numerous advances have been made in characterizing the phenotype, ontogeny, ultrastructure, and cytochemistry of the murine Thy-1+ dendritic epidermal cell (Thy-1+ EC), elucidation of its functional qualities has been hampered by the difficulty in preparing pure populations of these cells. We therefore sought to obtain expanded, purified populations of Thy-1+ EC using culture techniques. Since Thy-1+ EC are bone marrow-derived, density gradient enriched populations of freshly harvested epidermal cells (FH-EC) were placed in culture under conditions known or suspected to promote mitogenesis among leukocyte subsets. FH-EC prepared from truncal skin of C3H/HeN mice (Thy-1.2+) were cultured at 37 degrees C in 5% CO2 in complete medium (CM) of Eagle's Hanks' amino acid with 10% fetal calf serum, nutrients, and antibiotics at 10(6) FH-EC/well in 24-well culture plates. CM was supplemented with one or more of the following: concanavalin A (Con-A), interleukin-1/epidermal cell-derived thymocyte-activating factor (IL-1/ETAF), IL-2, IL-3, gamma interferon, indomethacin (IM), and anti-Thy-1.2 antibody. Media with appropriate supplements were changed every 2-3 days. Freshly isolated, enriched FH-EC contained 7-20% Thy-1+ EC (defined as brightly fluorescing cells readily distinguishable from weakly fluorescing keratinocytes), which also stained with antibodies directed against asialo GM1, Ly 5.1, and vimentin but did not stain with antibodies to other T cell-, B cell- or macrophage phenotypic markers. Analysis of 10 separate cultures revealed a 3- to 10-fold expansion of nonkeratinocyte Thy-1+ cells after 21 +/- 4 days in culture in CM supplemented with Con-A and IM, and 70-100% of viable cells after expansion were Thy-1+. Phenotypic analysis of expanded cells revealed the emergence in 10 separate cultures of one of two mutually exclusive distinct populations: one Thy-1+, asialo GM1+, L3T4- (natural killer phenotype) and the other Thy-1+, asialo GM1-, L3T4+ (T helper phenotype). Experiments designed to explain the emergence of an L3T4+ population suggest that phenotypic modulation occurred in vitro.  相似文献   
48.
限制饮食对健康和老化的益处已经逐渐被大家所认识。本文从学习、记忆、突触可塑性、神经再生等神经功能方面,回顾了最近有关限制饮食的基础及临床研究。目前认为限制饮食在神经功能方面发挥多种作用,其中较令人满意的解释是限制饮食作为一种应激原,能诱导机体内有利环境的形成。这个环境有利于促进神经可塑性,提高认知功能,刺激神经细胞再生和调节炎症反应。此外,许多分子包括热休克蛋白、神经营养因子、沉默调节蛋白1(SIRT1)等均参与了限制饮食对机体的保护作用。鉴于完全和长时间的限制饮食在人类实施的困难性,一些限制饮食模型的替代物开始被大家所重视。本文也对限制饮食模型的替代物的研究进行了分析和探讨。  相似文献   
49.
OBJECTIVE: Although radio-frequency ablation (RFA) has been recently applied as a minimally invasive treatment option for renal cell carcinoma (RCC), indication of this modality remains a critical issue due to the lack of complete tumor destruction as well as the uncertainty of its long-term efficacy. We report the efficacy of RFA for nine carefully selected patients with RCC who had significant reason to avoid invasive surgical treatment under general anesthesia. METHODS: Radio-frequency ablation was performed under epidural or local anesthesia by ultrasound or computed tomography (CT) guidance in nine patients with biopsy proven RCC (mean diameter, 38 mm; range, 20-53 mm), who were at significant operative or anesthetic risk for invasive surgery. Follow-up enhanced CT scans or magnetic resonance images were evaluated every 3-6 months and an evaluation of metastasis was performed every 6 months. RESULTS: At a mean follow-up of 17 months, seven (78%) of the nine patients with renal tumor showed no tumor enhancement. The renal function of all patients was well preserved. All patients were able to continue undergoing their respective treatments for active diseases in other organs in parallel to the RFA treatment. No distant metastasis, urine leakage were reported and one case of temporary hematuria and one case of peri-renal hemorrhage not requiring blood transfusion were encountered. Intra-operative ultrasonography was useful in the real-time monitoring of the minimally excessive extension of ablation into the normal parenchyma. CONCLUSION: Radio-frequency ablation appears to be an effective and safe minimally invasive therapeutic option for selected patients with RCC who have reason to avoid invasive surgery under general anesthesia.  相似文献   
50.
目的 :对黄芩汤及其经肠道菌群作用后的代谢产物的体内保肝作用进行比较研究。方法 :使用普通和伪无菌小鼠 ,用D-半乳糖胺造成肝脏损伤模型 ,分别给予黄芩汤和黄芩汤的代谢产物 ,测定给药 3d后血清中丙氨酸氨基转换酶 (ALT)和天门冬氨酸氨基转换酶 (AST)的活性。结果 :普通小鼠口服黄芩汤后 ,高、中剂量组小鼠血清中ALT水平明显下降 ,与模型组产生显著差异 ;伪无菌小鼠口服黄芩汤代谢产物之后 ,高、中剂量组血清中ALT水平显著下降 ,但黄芩汤 3个剂量组对其无相似的药理作用。结论 :黄芩汤经过肠道菌群作用后的代谢产物是体内产生保肝降酶作用的物质基础。  相似文献   
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