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61.
62.
应用脉冲多普勒超声心动图对30例使用1,6-二磷酸果糖的肺炎心衰患儿进行心室舒缩功能指标的观测,并以20例常规治疗的心衰患儿及20例正常儿为对照组,评价1,6-二磷酸果糖的疗效。结果表明,1,6-二磷酸果糖能明显改善PEP、PEP/ET、PEP/R-R、FVI和SV等心室收缩功能指标及PFVE、E/A、PFVA等心室舒张功能指标,使心功能恢复正常。1,6-二磷酸果糖对肺炎心衰引起的心肌缺血、缺氧有保护作用。 相似文献
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64.
Y M Chung T S Yeh Y Y Tsai H Chiang J H Liu 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1988,196(3):161-166
Lymphomatoid granulomatosis is an angiocentric and angiodestructive lympho-proliferative disorder involving multisystems but rarely conjunctiva. We present a 62-year-old Chinese female with lymphomatoid granulomatosis who had an ulcerative conjunctival nodule. Conjunctival biopsy revealed pathological findings important for diagnosis and indicating progression of disease severity. To our knowledge, this is the first report to demonstrate pathological findings characteristic of lymphomatoid granulomatosis with conjunctival involvement. 相似文献
65.
曹依群 《第二军医大学学报》2003,24(7):808-809
抗病毒药利巴韦林(ribavirin)被临床用于抗严重急性呼吸综合征(SARS)病毒,利巴韦林与激素联用对SARS的疗效肯定,但亦有一定不良反应。本文对其临床使用方法、疗效、不良反应及注意事项等作一综述。 相似文献
66.
Amy C Y Lo Alvin K H Cheung Victor K L Hung Chung-Man Yeung Qing-Yu He Jen-Fu Chiu Stephen S M Chung Sookja K Chung 《Journal of cerebral blood flow and metabolism》2007,27(8):1496-1509
Previously, we reported that transgenic mice overexpressing endothelin-1 in astrocytes showed more severe neurological deficits and increased infarct after transient focal ischemia. In those studies, we also observed increased level of aldose reductase (AR), the first and rate-limiting enzyme of the polyol pathway, which has been implicated in osmotic and oxidative stress. To further understand the involvement of the polyol pathway, the mice with deletion of enzymes in the polyol pathway, AR, and sorbitol dehydrogenase (SD), which is the second enzyme in this pathway, were challenged with similar cerebral ischemic injury. Deletion of AR-protected animals from severe neurological deficits and large infarct, whereas similar protection was not observed in mice with SD deficiency. Most interestingly, AR(-/-) brains showed lowered expression of transferrin and transferrin receptor with less iron deposition and nitrotyrosine accumulation. The protection against oxidative stress in AR(-/-) brain was also associated with less poly(adenosine diphosphate-ribose) polymerase (PARP) and caspase-3 activation. Pharmacological inhibition of AR by Fidarestat also protected animals against cerebral ischemic injury. These findings are the first to show that AR contributes to iron- and transferrin-related oxidative stress associated with cerebral ischemic injury, suggesting that inhibition of AR but not SD may have therapeutic potential against cerebral ischemic injury. 相似文献
67.
蕲蛇酶减轻大鼠局灶性脑缺血再灌注损伤的实验研究(Ⅱ) 总被引:2,自引:0,他引:2
目的 从病理形态学观察蕲蛇酶对大鼠局灶性脑缺血再灌注损伤的保护作用并探讨其机制。方法 采用线栓法制备大鼠大脑中动脉栓塞后再灌注模型,光镜及电镜观察缺血3h恢复血流再灌24h后脑组织形态学变化。TTC染色观察脑梗死面积,免疫组织化学方法检测脑组织碱性成纤维细胞生长因子(bFGF)的表达。用药组分别在缺血即刻或再灌即刻静脉给予不同剂量的蕲蛇酶,观察比较模型组和蕲蛇酶所有给药组之间上述指标的变化。结果 缺血即刻给蕲蛇酶4U/kg组较再灌即刻给蕲蛇酶同剂量组显著减小梗死灶(P〈0.001),减轻脑组织病理改变,并使脑组织中bFGF蛋白表达明显增多。结论 蕲蛇酶对脑缺血再灌注损伤的神经保护作用可能与脑组织中bFGF表达增高有关;提示该药早期使用更为有效。 相似文献
68.
Deficiency of insulin receptor substrate-1 impairs skeletal growth through early closure of epiphyseal cartilage. 总被引:5,自引:0,他引:5
Kazuto Hoshi Naoshi Ogata Takashi Shimoaka Yasuo Terauchi Takashi Kadowaki Shin-Ichi Kenmotsu Ung-Il Chung Hedehiro Ozawa Kozo Nakamura Hiroshi Kawaguchi 《Journal of bone and mineral research》2004,19(2):214-223
Morphological analyses in and around the epiphyseal cartilage of mice deficient in insulin receptor substrate-1 (IRS-1) showed IRS-1 signaling to be important for skeletal growth by preventing early closure of the epiphyseal cartilage and maintaining the subsequent bone turnover at the primary spongiosa. Introduction: IRS-1 is an essential molecule for intracellular signaling by IGF-I and insulin, both of which are potent anabolic regulators of cartilage and bone metabolism. To clarify the role of IRS-1 signaling in the skeletal growth, morphological analyses were performed in and around the epiphyseal cartilage of mice deficient in IRS-1 (IRS-1(-/-)), whose limbs and trunk were 20-30% shorter than wildtype (WT) mice. MATERIALS AND METHODS: The epiphyseal cartilage and the primary spongiosa at proximal tibias of homozygous IRS-1(-/-) and WT male littermates were compared using histological, immunohistochemical, enzyme cytohistochemical, ultrastructural, and bone histomorphometrical analyses. RESULTS: In and around the WT epiphyseal cartilage, IRS-1 and insulin-like growth factor (IGF)-1 receptors were widely expressed, whereas IRS-2 was weakly localized in bone cells. Chronological observation revealed that height of the proliferative zone and the size of hypertrophic chondrocytes were decreased in WT mice as a function of age, and these decreases were accelerated in the IRS-1 (-/-) cartilage, whose findings at 12 weeks were similar to those of WT at 24 weeks. In the IRS-1(-/-) cartilage, proliferating chondrocytes with positive proliferating cell nuclear antigen (PCNA) or parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor immunostaining had almost disappeared by 12 weeks. Contrarily, TUNEL+ apoptotic cells were increased in the hypertrophic zone, at the bottom of which most of the chondrocytes were surrounded by the calcified matrix, suggesting the closure of the cartilage. In the primary spongiosa, bone volume, alkaline phosphatase (ALP)+ osteoblasts, TRACP+ osteoclasts, and the osteopontin-positive cement line were markedly decreased. Bone histomorphometrical parameters for both bone formation and resorption were significantly lower in IRS-1(-/-) mice, indicating the suppression of bone turnover. CONCLUSION: The IRS-1(-/-) epiphyseal cartilage exhibited insufficient proliferation of chondrocytes, calcification of hypertrophic chondrocytes, acceleration of apoptosis, and early closure of the growth plate. Thus, the data strongly suggest that IRS-1 signaling is important for the skeletal growth by preventing early closure of the epiphyseal cartilage and by maintaining the subsequent bone turnover at the primary spongiosa. 相似文献
69.
70.
Establishment of a human hepatocellular carcinoma cell line highly expressing sodium iodide symporter for radionuclide gene therapy. 总被引:6,自引:0,他引:6
Joo Hyun Kang June-Key Chung Yong Jin Lee Jae Hoon Shin Jae Min Jeong Dong Soo Lee Myung Chul Lee 《Journal of nuclear medicine》2004,45(9):1571-1576
To evaluate the possibility of radionuclide gene therapy and imaging in hepatocellular carcinoma cancer, we investigated the iodine accumulation of a human hepatocellular carcinoma cell line, SK-Hep1, by transfer of human sodium iodide symporter (hNIS) gene. By targeting NIS expression in SK-Hep1, we could also investigate whether these cells concentrate 99mTc-pertechnetate and 188Re-perrhenate as well as 125I in vitro and in vivo. METHODS: The hNIS gene was transfected to human hepatocellular carcinoma SK-Hep1 cell lines using lipofectamine plus reagent. The uptake and efflux of 125I, 99mTc-pertechnetate, and 188Re-perrhenate were measured in the transfected and parental cells. Biodistribution was studied in nude mice bearing SK-Hep1 and SK-Hep1-NIS at 10 and 30 min and at 1, 2, 6, 16, and 23 h after injection of 125I, 99mTc- pertechnetate, or 188Re-perrhenate. In tumor imaging studies, the nude mice were intravenously injected with 188Re-perrhenate and imaged with a gamma-camera equipped with a pinhole collimator at 30 and 60 min after injection. The survival rate (%) was determined by the clonogenic assay after 37 MBq/10 mL (1 mCi/10 mL) 131I and 188Re-perrhenate treatment. RESULTS: SK-Hep1-NIS, stably expressing the NIS gene, accumulated 125I up 150 times higher than that of SK-Hep1. Iodine uptake of SK-Hep1-NIS is completely blocked by perchlorate. NIS gene transfection into SK-Hep1 also resulted in 112- and 87-fold increases of 99mTc-pertechnetate and 188Re-perrhenate uptake, respectively. Iodide efflux from SK-Hep1-NIS was relatively slow, with only 10% released during the initial 5 min, and 60% remained at 25 min. In the biodistribution study using SK-Hep1-NIS-xenographed mice, the tumor uptake of 125I, 188Re-perrhenate, and 99mTc-pertechnetate was 68.0 +/- 15.0, 46.2 +/- 9.1, and 59.6 +/- 16.2 %ID/g (percentage injected dose per gram) at 2 h after injection, respectively. After 188Re-perrhenate injection in SK-Hep1 and SK-Hep1-NIS-xenographed nude mice, whole-body images clearly visualized the SK-Hep1-NIS tumor, whereas the control tumor was not visualized. The survival rate (%) of SK-Hep1-NIS was markedly reduced to 46.3% +/- 10.1% and 28.9% +/- 5.2% after 37 MBq/mL (1 mCi/10 mL) 131I and 188Re-perrhenate treatment compared with the survival rates of the parental cells. These results demonstrated that SK-Hep1-NIS could be selectively killed by the induced 131I and 188Re-perrhenate accumulation through NIS gene expression. CONCLUSION: NIS-based gene therapy using beta-emitting radionuclides has the potential to be used in hepatocellular carcinoma management. 相似文献