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121.
Bone formation has been shown to be stimulated by local diathermy in vivo; however, the mechanisms involved in this heat-induced osteogenesis are unclear. In this study, we investigated the direct effect of temperature on human bone marrow-derived stromal cells (BMSCs) and the human osteoblast-like, osteosarcoma-derived MG-63 cells in culture conditions. Both cell types were shown to tolerate the transient exposure to mild heat shock conditions (1 h at 39-41 degrees C), and long-term (96 h) exposure at 39 degrees C stimulated DNA synthesis in BMSC but caused growth arrest in MG-63 cells. Furthermore, 1-h exposure to higher temperatures (42.5-45 degrees C) or continuous 96-h exposure to 40 degrees C or 41 degrees C inhibited the proliferation of both BMSCs and MG63 cells. The level of alkaline phosphatase (ALP) in these cells linearly correlated with the increase in temperature, and the ALP expression, either at the basal level or in response to 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], was enhanced after a single 1-h exposure to 42.5 degrees C. In addition, continuous incubation at 39 degrees C or repeated transient exposure to 39/41 degrees C greatly enhanced the ability of BMSCs to form mineralizing nodules. The heat shock protein HSP70, which was expressed constitutively by BMSCs, was found to be up-regulated by hyperthermia (39 degrees C) and down-regulated at 33 degrees C. The expression of HSP70 could be induced in MG-63 cells by both low- and high-temperature conditions. These data suggest that treatment with a mild heat shock induces the proliferation and differentiation of osteoprogenitor cells, and the direct effects of temperature on bone-forming cells might be one of the mechanisms involved in heat-induced bone formation in vivo. 相似文献
122.
123.
TGF-β1在烧伤合并内毒素血症骨髓粒单系造血变化中的作用 总被引:2,自引:2,他引:0
目的 探讨TGF-β1与c-kit相互关系及其在烧伤合并内毒素血症骨髓粒单系造血变化中的作用。方法 采用免疫组化法检测20%TBSAⅢ度烧伤合并内毒素(1μg/g体重)腹腔注射后1周内小鼠骨髓细胞TGF-β1、c-kit表达,并对骨髓粒单系造血变化进行了动态观察。结果 烧伤合并内毒素血症早期骨髓粒单系略呈增生反应,继而呈现造血抑制,烧注后1、3d骨髓细胞TGF-β1表达增强,c-kit表达减弱,且TGF-β1与骨髓CFU-GM和c-kit变化趋势相反。结论 TGF-β1在烧伤合并内毒素血症骨髓粒单系造血抑制中起着重要作用。其机制与下调骨髓细胞c-kit表达有关。 相似文献
124.
125.
Percutaneous drainage access: a simplified coaxial technique 总被引:1,自引:0,他引:1
vanSonnenberg E; Wittich GR; Schiffman HR; Cabrera OA; Willson SA; Quinn SF; Casola G; Hayne LA; Polansky AD 《Radiology》1986,159(1):266-268
We describe an access technique that we have used in 150 nephrostomy and biliary drainage procedures and for access to some abscesses and viscera. The system provides safe coaxial access with a 22-gauge removable hub needle, which then acts as a guide wire and is replaced by an 18-gauge cannula. A major advantage is that only one guide wire is used (0.038-inch) for the entire drainage procedure. No significant complications have occurred to date with this method. 相似文献
126.
Interventional radiology in the spleen 总被引:2,自引:0,他引:2
Despite the widespread use of interventional radiologic techniques, there has been reluctance to apply these to the spleen. Concern for bleeding and difficulty in negotiating around the colon and pleura have limited its use. The authors report their experience with interventional radiology of the spleen in 35 cases, including percutaneous biopsy (n = 5), diagnostic and therapeutic fluid aspiration (n = 14), and catheter drainage of abscesses (n = 9), hematomas (n = 2), intrasplenic pancreatic pseudocysts (n = 2), and necrotic tumor (n = 1). Transsplenic fluid aspiration and biopsy of the pancreas and adrenal gland were performed as well (n = 2). All procedures were performed under computed tomographic or ultrasound guidance. Biopsies were performed with 22- or 20-gauge needles only; no complications were encountered. Diagnoses included primary and secondary malignancies and an infectious process. Drainages were successful in 11 of 14 patients; pleural effusions occurred in two cases, but neither required specific therapy. Interventional radiologic procedures in the spleen are feasible, and the authors discuss methods to promote their safe application. 相似文献
127.
荨麻疹是夏季常见的一种过敏性皮肤病,据统计,1/5以上的人一生至少得过一次荨麻疹。但是,荨麻疹的病因比较复杂,约有半数以上病例找不到原因…… 相似文献
128.
Musculoskeletal neoplasms after intraarterial chemotherapy: correlation of MR images with pathologic specimens 总被引:6,自引:0,他引:6
The most accurate prognostic indicator in patients with musculoskeletal sarcomas is the percentage of tumor necrosis after intraarterial chemotherapy. Magnetic resonance (MR) imaging was evaluated to determine its ability to indicate the percentage of necrosis in musculoskeletal neoplasms after treatment. Fourteen patients with musculoskeletal neoplasms underwent treatment protocols including intraarterial chemotherapy (n = 14), radiation therapy (n = 6), and systemic chemotherapy (n = 14). All patients underwent MR imaging before and after treatment, and all underwent either limb salvage surgery (n = 8) or amputation (n = 6) within 1 week of the last MR examination. Standard unehanced spin-echo T1-, spin-density-, and T2-weighted MR sequences were used. The MR images were compared with the pathologic specimens. On T2-weighted images, the signal intensities of viable tumor, tumor necrosis, edema, hemorrhage, and necrosis overlapped. With the unenhanced spin-echo technique, MR imaging cannot be used to predict the percentage of tumor necrosis in musculoskeletal neoplasms after intraarterial chemotherapy. 相似文献
129.
Anti-Sc1 was detected in a gravida-2 patient at 12 weeks' gestation. At 29 weeks, the antibody was found to be of the IgG3 subclass with a titer of 16, score 36, by the indirect antiglobulin test, and it produced 7 percent lysis by antibody-dependent cellular cytotoxicity (ADCC) assay, a finding that suggested an unaffected fetus. The titer remained constant throughout the pregnancy, as did the IgG subclass and activity in the ADCC assay. At delivery of the full-term infant, the cord hemoglobin was 13.5 g per dL and the direct antiglobulin test was positive (3+) with anti-IgG. The infant did not require transfusion. A sample taken 9 weeks after delivery showed 44 percent lysis in the ADCC assay. The anti-Sc1 titer was 32, score 65. 相似文献
130.
新型人工肝--分子吸附再循环系统及其临床应用 总被引:8,自引:0,他引:8
到目前为止,急慢性重型肝炎的治疗仍强调基础护理和一般的支持对症处理,缺乏清除肝脏毒素和促进肝细胞再生的有效手段。虽然血液透析、灌流和血浆置换已被用于重型肝炎的治疗,但其临床疗效尚未被公认。与上述血液净化方法不同的是,新型人工肝——分子吸附再循环系统在有效清除水溶性中小毒素分子的同时,还可以选择性清除亲脂性及与血浆白蛋白相结合的毒素分子,并保留血液中有用的重要营养物质和蛋白质。本文对这一新型人工肝支持系统的基本原理、使用方法、不良反应及临床应用研究进展作了综述。 相似文献