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991.
目的探讨颈椎不稳症的影像学诊断。方法回顾性分析50例经临床证实的颈椎不稳症患者的X线平片、CT和MRI检查资料。结果50例中上颈椎不稳16例,其中,寰枕关节不稳2例,表现为枕底—齿突线和斜坡—齿突线不连续,14例为寰枢关节不稳,其中,寰枢关节脱位7例;下颈椎不稳34例,其中,前屈不稳20例,后伸不稳14例。结论X线平片、CT和MRI综合分析能对颈椎不稳症作出准确的诊断。 相似文献
992.
目的研究高脂肪膳食诱导的胰岛素抵抗(IR)大鼠下丘脑及脂肪组织中增食欲素和瘦素系统的变化,分析其可能的调控因素。方法IR大鼠模型采用高脂肪膳食诱导并经钳夹技术证实;应用RT-PCR技术检测增食欲素及其受体(OX1R、OX2R)和瘦素受体(LR)以及脂肪组织中瘦素基因mRNA的表达;采用生化比色法测定血清游离脂肪酸(FFA)、放射免疫法测定血清肿瘤坏死因子α(TNF-α)。结果钳夹技术中葡萄糖输注率明显低于对照组;高脂肪膳食诱导的IR大鼠下丘脑中前增食欲素原mRNA的表达较对照组减少约80%(P<0.01);OX1R、OX2R分别增加3.4及3.2倍(P<0.01);瘦素mRNA增加约8倍(P<0.01);LR减少78%;血清FFA和TNF-α均明显高于对照组(P<0.01)。结论高脂肪膳食可诱导大鼠体内IR,并导致增食欲素和瘦素系统平衡状态的破坏;增食欲素和瘦素是机体能量平衡调节网络中的一对重要物质,两者相互作用共同维持机体能量代谢的稳定。血清FFA和TNF-α均可能参与该系统的调控,合理膳食在这一调控中至关重要。 相似文献
993.
Salleh Ibrahim Chao-Long Chen Chih-Che Lin Chin-Hsiang Yang Chih-Chi Wang Shih-Ho Wang Yeuh-Wei Liu Chee-Chien Yong Allan Concejero Bruno Jawan Yu-Fan Cheng 《Liver transplantation》2006,12(6):950-957
Complications in a donor are a distressing but inevitable occurrence, since graft procurement is a major undertaking. Although the technique for procurement has some similarities to hepatic resection, a donor is very unlike a patient with malignancy. The risk factors identified in these patients cannot be extrapolated to donors. Donor hepatectomy carried out from June 1995 to March 2005 in Chang Gung Memorial Hospital, Kaohsiung Medical Center was reviewed with the aim of identifying risk factors for complications. There were 204 living donor liver transplants, with 205 donor hepatectomies, as 1 living donor liver transplantation was a dual graft. Ten donors (4.88%) suffered complications. There was no difference in terms of age, gender, body weight, operation, and parenchymal time between those who had complications and those who did not. There was also no difference in liver function tests between the 2 groups of donors, but the total bilirubin was significantly higher in donors with complications. The graft weight and remnant liver volume were also similar. The proportion of donors with fatty liver was the same between the 2 groups. The mean blood loss in donors with complications was 170 +/- 79 mL, and that for donors without complications was 95 +/- 77 mL. There was a statistically significant greater blood loss in donors with complications (P < 0.05). The number of segments removed in donors with complications was also higher compared to donors without complications (P < 0.03). Using multivariate analysis, intraoperative blood loss and the number of segments removed were found to be independent risk factors for donor complications. Intraoperative blood loss during graft procurement must be kept low to minimize complications in donors. 相似文献
994.
红藻氨酸作用后海马神经元胞膜表面的超微结构的原子力显微镜观察 总被引:4,自引:0,他引:4
目的 观察原代培养神经元在红藻氨酸(KA)作用下细胞表面形态的三维构像变化。方法 利用原子力显微镜(AFM)对大鼠海马神经元经不同浓度的KA(25和250μmol/L,50和100nmol/L)分别作用10min和100min后的表面结构进行纳米级水平扫描和观测。结果 正常海马神经元表面光滑,起伏均匀、规律;KA作用后神经元呈退行性改变,表现为胞体肿胀,胞膜表面粗糙,出现隆起和“孔洞”样结构,并且其变化程度分别与作用时问和KA浓度呈量-效关系。结论 KA对海马神经元毒性作用后胞膜表面超微结构所产生的明显变化,可借助AFM清晰观察,并定量分析。 相似文献
995.
骨肉瘤细胞特异性结合短肽的筛选 总被引:2,自引:1,他引:1
目的:获得与骨肉瘤细胞株os-732特异结合的短肽,作为骨肉瘤靶向治疗的先导化合物。方法:以骨肉瘤细胞os-732为靶细胞,成骨细胞为吸附细胞对噬菌体12肽库进行差减筛选,用细胞ELISA、免疫组化鉴定阳性噬菌体克隆并测序。结果:经三轮筛选,从随机挑选的20个噬菌体克隆中得到9个特异性与骨肉瘤细胞os-732结合,而不与正常成骨细胞结合的阳性克隆。但其氨基酸序列无同源性。结论:得到多个序列不同的特异性结合骨肉瘤的噬菌体克隆,提示骨肉瘤细胞表面结构复杂,具多个骨肉瘤抗原表位。本实验获得的短肽具有一定的亲合力和肿瘤特异性,为针对不同位点的靶向药物设计提供了实验依据。 相似文献
996.
目的研究超声对乳腺肿块的鉴别诊断价值及其病理基础。方法选取由超声诊断,并经手术病理证实的74例乳腺肿块,分析其二维超声的形态、边缘轮廓、包膜、边界及内部回声、肿块后方回声及侧方声影等表现特征,结合肿块内部及周边的血流情况,将其分为良恶性,并与病理结果对照。结果二维超声诊断乳腺肿块良恶性的准确率为81.2%,二维超声联合彩色多普勒超声及能量多普勒超声后诊断乳腺肿块良恶性的准确率提高为89.1%。结论二维超声结合彩色多普勒超声及能量多普勒超声检查,可提高乳腺良恶性肿块的诊断正确率。 相似文献
997.
目的:观察影像学和脑电图对儿童缺氧缺血性脑病的应用对照及意义。方法:对65例缺氧缺血性患儿作影像学和脑电图检查。结果:脑电图正常6例(9.23%),轻度异常13例(22.03%),中度异常37例(61.03%),重度异常9例(16.94%),脑电图异常率为90.77%。脑电图异常表现为弥漫性慢波增多和局限性癎性放电。影像学异常44例,异常率为67.69%。结论:影像学和脑电图检查对儿童缺氧缺血性脑病的诊断及治疗有一定的帮助。 相似文献
998.
OBJECTIVE: To observe the morphological changes of Balb/C mouse embryonic stem cells following directed differentiation into pancreatic islet-like cell clusters (PICC) in vitro using atomic force microscope (AFM). METHODS: Balb/C mouse embryonic stem cells were first cultured into embryonic bodies (EBs) and allowed to differentiate spontaneously for 4 days. The cells were then transferred to gelatin-coated dishes for the EBs to attach and spread on the tissue culture plates, in the course of which a series of cell growth factors such as basic fibroblast growth factor (bFGF), insulin-like growth factor 1 (IGF-1) and nicotinamide were added into the culture medium at specific time points to induce directed differentiation of the stem cells into PICC. Immunocytochemistry was employed to detect the cells positive for insulin and glucagon, which were observed with AFM. RESULTS: The embryonic stem cells developed into cell clusters of different sizes, in which the cells were tightly arranged. Islet B cells were numerous in the center of clusters and darkly stained, but fewer in the peripherals with lighter stains. Islet A cells expressing glucagon were relatively fewer in the cell clusters, found mainly in the peripherals. Scanning of the insulin-positive clusters by AFM revealed large quantity of tissue fibers resembling nerve fibers that formed a reticular structure in disorderly arrangement. Numerous round granules were observed in the cytoplasm of almost identical sizes ranging from 0.5 to 1.0 mum in diameter. CONCLUSION: The cell clusters obtained by directed differentiation are mature in both morphology and function with also well organized structures. 相似文献
999.
Internalization of sst2, sst3, and sst5 receptors: effects of somatostatin agonists and antagonists. 总被引:4,自引:0,他引:4
Renzo Cescato Stefan Schulz Beatrice Waser Véronique Eltschinger Jean E Rivier Hans-Jürgen Wester Michael Culler Mihaela Ginj Qisheng Liu Agnes Schonbrunn Jean Claude Reubi 《Journal of nuclear medicine》2006,47(3):502-511
The uptake of radiolabeled somatostatin analogs by tumor cells through receptor-mediated internalization is a critical process for the in vivo targeting of tumoral somatostatin receptors. In the present study, the somatostatin receptor internalization induced by a variety of somatostatin analogs was measured with new immunocytochemical methods that allow characterization of trafficking of the somatostatin receptor subtype 2 (sst2), somatostatin receptor subtype 3 (sst3), and somatostatin receptor subtype 5 (sst5) in vitro at the protein level. METHODS: Human embryonic kidney 293 (HEK293) cells expressing the sst2, sst3, or the sst5 were used in a morphologic immunocytochemical internalization assay using specific sst2, sst3 and sst5 antibodies to qualitatively and quantitatively determine the capability of somatostatin agonists or antagonists to induce somatostatin receptor internalization. In addition, the internalization properties of a selection of these agonists have been compared and quantified in sst2-expressing CHO-K1 cells using an ELISA. RESULTS: Agonists with a high sst2-binding affinity were able to induce sst2 internalization in the HEK293 and CHO-K1 cell lines. New sst2 agonists, such as Y-DOTA-TATE, Y-DOTA-NOC, Lu-DOTA-BOC-ATE (where DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid; TATE is [Tyr3, Thr8]-octreotide; NOC is [1-NaI3]-octreotide; and BOC-ATE is [BzThi3, Thr8]-octreotide), iodinated sugar-containing octreotide analogs, or BIM-23244 were considerably more potent in internalizing sst2 than was DTPA-octreotide (where DTPA is diethylenetriaminepentaacetic acid). Similarly, compounds with high sst3 affinity such as KE108 were able to induce sst3 internalization. In sst2- or sst3-expressing cell lines, agonist-induced receptor internalization was efficiently abolished by sst2- or sst3-selective antagonists, respectively. Antagonists alone had no effect on sst2 or sst3 internalization. We also showed that somatostatin-28 and somatostatin-14 can induce sst5 internalization. Unexpectedly, however, potent sst5 agonists such as KE108, BIM-23244, and L-817,818 were not able to induce sst5 internalization under the same conditions. CONCLUSION: Using sensitive and reproducible immunocytochemical methods, the ability of various somatostatin analogs to induce sst2, sst3, and sst5 internalization has been qualitatively and quantitatively determined. Whereas all agonists triggered sst2 and sst3 internalization, sst5 internalization was induced by natural somatostatin peptides but not by synthetic high-affinity sst5 agonists. Such assays will be of considerable help for the future characterization of ligands foreseen for nuclear medicine applications. 相似文献
1000.
约氏疟原虫感染不同小鼠免疫分子的应答差异 总被引:2,自引:1,他引:1
目的探讨在约氏疟原虫感染过程中不同宿主的免疫应答差异。方法以约氏疟原虫(致死型)感染DBA/2和BALB/c小鼠,计算红细胞感染率;收集感染前和感染后1、3、6、9、12、15、20d小鼠血清,并无菌取出脾脏,培养脾细胞。应用ELISA试剂盒检测小鼠血清中IFN-γ和IL-12水平,并通过Griess方法检测脾细胞培养上清中NO含量。结果DBA/2小鼠的原虫血症峰值水平明显低于BALB/c小鼠,并于感染后第20d左右自愈;BALB/c小鼠于原虫血症达到峰值水平后全部死亡;DBA/2小鼠的IFN-γ和IL-12水平于感染后1d即出现了有意义的升高并持续到第20d;BALB/c小鼠的IFN-γ和IL-12水平仅干感染后1d出现了有意义的升高;DBA/2小鼠NO的产生于感染后3d出现了有意义的升高,第6d达到峰值,而BALB/c小鼠的NO水平始终未见明显升高。结论DBA/2小鼠通过感染早期Th1细胞免疫应答的有效建立能够抑制原虫血症,IL-12是启动并维持Th1细胞免疫应答的关键性细胞因子。 相似文献