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61.
M K Song W Y Shin N F Adham N V Costea 《The American journal of clinical nutrition》1989,49(4):701-707
The effects of different amounts of dietary zinc on the Zn absorption rate and on Zn, calcium and magnesium concentrations in tissues of MOPC 104E tumor-bearing Balb/c mice were determined. The Zn absorption rate was inversely related to the amounts of Zn in their diets and was lower than that of nontumor-bearing control mice fed a laboratory mice chow. Zn concentrations of tumor-bearing mice were also low compared with control mice but tumor Zn concentrations, regardless of the concentrations of Zn in the diets, were higher than those of normal tissues of the host other than the pancreas. Ca concentrations in tumor and tissues of tumor-bearing mice were higher than in control animals but Mg concentrations in tissues of tumor-bearing mice appeared to be similar to those of control mice. Results suggest that tumor-bearing mice have a lower intestinal Zn absorption capacity and a higher Zn uptake rate causing other tissues to become hypozincemic and hypercalcemic. 相似文献
62.
膳食黑米皮抑制高脂诱导的家兔动脉粥样硬化形成及其机制的初步探讨 总被引:1,自引:0,他引:1
目的 探讨膳食黑米皮对高脂诱导的家兔动脉粥样硬化形成的影响及其作用机制。方法 24只雄性新西兰大耳白家兔,按体重随机分为3组,分别饲以正常基础饲料、高脂饲料(含96%基础饲料、0.5%胆固醇、3.5%猪油)、黑米皮饲料(含 91%基础饲料、0.5%胆固醇、3.5%猪油、5%黑米皮),实验期为 60d。用图像分析法测定各组家兔主动脉脂质斑块面积,并分析家兔氧化与抗氧化状态。结果 黑米皮实验家兔的主动脉壁斑块面积较高脂组低66%(P<0.001);黑米皮组实验家兔的主动脉壁8-ohdG含量和血清及主动脉壁中MDA水平也低于高脂组(P<0.05 );而红细胞及主动脉壁中SOD水平和血清α-生育酚含量在两个处理组之间差异无显著性。结论 膳食黑米皮可以抑制高脂诱导的家兔动脉粥样硬化形成,其机制可能与之降低机体氧化应激水平及过氧化脂质生成有关。 相似文献
63.
Sherry X Yang Richard M Simon Antoinette R Tan Diana Nguyen Sandra M Swain 《Clinical cancer research》2005,11(17):6226-6232
PURPOSE: To delineate gene expression patterns and profile changes in metastatic tumor biopsies at baseline and 1 month after treatment with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib in patients with metastatic breast cancer. EXPERIMENTAL DESIGN: Patients were treated with 150 mg of oral erlotinib daily. Gene expression profiles were measured with Affymetrix U133A GeneChip and immunohistochemistry was used to validate microarray findings. RESULTS: Estrogen receptor (ER) status by immunohistochemistry is nearly coincided with the two major expression clusters determined by expression of genes using unsupervised hierarchical clustering analysis. One of 10 patients had an EGFR-positive tumor detected by both microarray and immunohistochemistry. In this tumor, tissue inhibitor of metalloproteinases-3 and collagen type 1 alpha 2, which are the EGF-down-regulated growth repressors, were significantly increased by erlotinib. Gene changes in EGFR-negative tumors are those of G-protein-linked and cell surface receptor-linked signaling. Gene ontology comparison analysis pretreatment and posttreatment in EGFR-negative tumors revealed biological process categories that have more genes differentially expressed than expected by chance. Among 495 gene ontology categories, the significant differed gene ontology groups include G-protein-coupled receptor protein signaling (34 genes, P = 0.002) and cell surface receptor-linked signal transduction (74 genes, P = 0.007). CONCLUSIONS: ER status reflects the major difference in gene expression pattern in metastatic breast cancer. Erlotinib had effects on genes of EGFR signaling pathway in the EGFR-positive tumor and on gene ontology biological process categories or genes that have function in signal transduction in EGFR-negative tumors. 相似文献
64.
保留肾单位手术治疗早期小肾癌21例临床分析 总被引:1,自引:0,他引:1
Yao-Jun Xiao Shao-Bin Zheng Wan-Long Tan Tong Chen Huan Qi Zhi-Qiang Shao Yao-Dong Jiang Peng Wu Hui-Jian Zhang 《第一军医大学学报》2005,25(3):357-359
OBJECTIVE: To evaluate the clinical effects of nephron-sparing surgery in patients with early-stage small renal cell carcinoma. METHODS: Nephron-sparing surgery was performed in 21 patients with renal cell carcinoma including 1 with solitary kidney, 3 with unilateral tumor and contralateral renal compromise, and 17 with unilateral tumor and normal contralateral kidney. The diameter of the tumors ranged from 1.5 to 6.0 cm, with a mean of 2.8 cm. The tumor diameter in 17 patients with normal contralateral kidney was less than 4 cm (mean 2.5 cm) and the average diameter in 4 patients with contralateral renal compromise was 4.2 cm. Sixteen cases were in stage T(1), 4 in stage T(2), and 1 in stage T(3). Of the 21 patients, 4 underwent tumor enucleation, 10 polar nephrectomy and 7 wedge resection. RESULTS: All patients were followed up for an average of 40.8 months (7 to 66 months). One patient suffered a right lung and mediastinum metastasis 3 years after the surgery later and 1 with chronic glomerulonephritis required dialysis 27 months after the operation. No surgical complication or local recurrence were found in other patients. CONCLUSION: As a safe and effective therapy for early-stage small renal cell carcinoma, nephron-sparing surgery can be considered as the gold-standard therapy for patients with lesions less than 4 cm in T(1) and T(2) stages of localized unilateral tumor with normal contralateral kidney. 相似文献
65.
66.
Seok L Ong Gianpiero Gravante Cristina A Pollard M'Balu A Webb Severine Illouz Ashley R Dennison 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2009,11(8):613-621
Pain control is one of the most challenging aspects in the management of chronic pancreatitis. Total pancreatectomy can successfully relieve the intractable abdominal pain in these patients but will inevitably result in insulin-dependent diabetes. Islet autotransplantation aims to preserve, as far as possible, the insulin secretory function of the islet cell mass thereby reducing (or even removing) the requirement for exogenous insulin administration after a total pancreactomy. Despite the relatively small number of centres able to perform these procedures, there are important technical variations in the details of their approaches. The aim of this review is to provide details of the current surgical practice for total pancreatectomy combined with islet autotransplantation, and outline the potential advantages and disadvantages of the variations adopted in each centre. 相似文献
67.
S.L. Ezekiel Tan 《Injury》2009,40(7):683-691
The goal of fracture fixation is to achieve bone healing and restore the function of the injured limb in the shortest possible time without compromising safety. Newer technologies such as the locking compression plate (LCP) and its derivatives are valuable additions to the orthopaedic traumatologist's armamentarium. As with any emerging technology, the indications will be extended until a threshold is reached and the limitations of the technology are seen. It is vital that surgeons involved in fracture care are aware of when locked plating is superior to other methods and also when they should use another treatment modality.This paper reviews the use of locked plating as a fixation method. Five topics covered in this review are: a historical perspective on locked plating, general indications, specific modes and techniques, patterns of failure, and an anatomical overview of current indications for locked plating. 相似文献
68.
69.
新型纳米根管充填材料对成骨细胞生长的影响 总被引:2,自引:0,他引:2
通过体外培养的成骨细胞,采用二甲基噻唑二苯基四唑溴盐比色法和流式细胞术对新型纳米根管充填材料(nHA-PA66)作用下的成骨细胞生长情况的变化进行研究,评价其对成骨细胞生长的影响。以该材料的细胞培养基浸提液作用于实验组细胞,对照组采用培养基本身。实验组和对照组成骨细胞的生长情况和细胞周期无显著性差异,表明该新型纳米材料对成骨细胞的生长和细胞周期无不良影响。提示新型纳米根管充填材料的成骨细胞相容性较好,具有用作根充材料的基础。 相似文献
70.
甲氧苄氨嘧啶—PVP共沉淀物的研究 总被引:1,自引:0,他引:1
本工作用差示扫描量热法(DSC)研究甲氧苄氨嘧啶与PVP溶剂法制备的共沉淀物,表明已不存在甲氧苄氨嘧啶晶体。用x射线衍射法研究了1:12共沉淀物,证明无甲氧苄氨嘧啶的晶体衍射峰。经分光光度法测定结果,1:12共沉淀物比原药的溶解度大28.3倍。 相似文献