Time-dependent astroglial changes after gamma knife radiosurgery in the rat forebrain

OBJECTIVE: Using an experimental rat model and a clinically relevant treatment dose, we performed gamma knife radiosurgery to define the hyperacute radiation effects in normal rat forebrain, the time dependence of the astrocytic reaction, and the participation of astrocytes in the healing process after single-dose gamma radiation injuries. METHODS: Seventy-one rats underwent radiosurgical treatment (4-mm collimator) of the caudate-putamen nucleus (single-fraction maximal dose of 100 Gy) and were killed at times ranging from 3 hours to 90 days. Serial cryostat brain sections were processed with the immunohistochemical avidin-biotin complex technique, using anti-glial fibrillary acidic protein as the primary antibody (to identify astrocytes). RESULTS: Vascular changes, including endothelial hyperplasia and vessel wall thickening, were identified as the earliest postradiation manifestations and continued throughout the observation period. Astrocytes reacted to the radiation injury with hyperplasia and hypertrophy. At earlier time points (3-24 h), proliferation was the predominant reaction. The expression of glial fibrillary acidic protein in the proliferating and hypertrophic astrocytes formed an initial peak in the adjacent corpus callosum 3 days after radiosurgery and peaked within the target site between 14 and 30 days. Astrocytic proliferation and hypertrophy were also observed in distant cortices (frontal, parietal, insular, and piriform cortices) and in the hippocampus. No necrosis was observed less than 30 days after irradiation. By Day 90, necrotic lesions with a mean diameter of 4 mm were identified, with glial scar at their peripheries. Astrocytic morphological features varied according to the distance from the necrosis. The irradiated side contained more glial fibrillary acidic protein-containing cells than did the nonirradiated contralateral side. CONCLUSION: During the early phase after radiation, vasculopathy was the first morphological change and may serve as the initiating factor for subsequent changes. Reactive astrocytes appeared not only at the target site but also in the surrounding regions; the severity of injury was determined by the distance from the target.     

大肠癌患者骨髓微转移的基因研究

目的 探讨大肠癌患者骨髓中微转移基因检测的意义。方法 应用聚合酶链式反应－单链构象多态性分析（ＰＣＲ－ＳＳＣＰ）／银染技术,检测５１例大肠癌患者手术前、后不同时间骨髓中ｐ５３和Ｋ－ｒａｓ基因的突变状况。结果 ５１例患者术前骨髓中基因突变阳性者１９例,阳性率３７．２５％。阳性检出与Ｄｕｋｅ’ｓ分期、淋巴转移显著相关。术后经２～３个疗程的化疗后,１９例基因突变阳性的患者中１１例转阴。结论 大肠癌患者骨     

静脉注射硝酸甘油诱导大鼠脑膜核因子-κB表达增强

目的观察偏头痛大鼠模型不同时相脑膜核因子-κB(NF-κB)的表达特征.方法采用静脉注射硝酸甘油(GTN)法建立大鼠偏头痛模型,应用免疫组织化学法观察对照组、GTN iv 后0.5,1.0, 1.5, 2.0, 4.0 h组脑膜NF-κB阳性染色细胞的分布,采用Western印迹法观察相应时间点脑膜核NF-κB的蛋白表达量.结果 GTN iv后0.5 h即出现大鼠脑膜NF-κB核阳性反应和核NF-κB蛋白表达量增高,1.5 h核NF-κB蛋白表达量达高峰,然后逐渐回落,至4 h接近正常水平.结论 GTN iv后早期脑膜呈时限性核NF-κB蛋白表达增强,提示NF-κB蛋白表达增强可能与偏头痛有关.     

国产班布罗的平喘作用

目的　研究国产班布特罗的平喘作用。方法　采用豚鼠整体引喘法及兔肺溢流法。结果　班布特罗 (ig ,1 4、2 8、5 6mg·kg-1)同间羟叔丁肾上腺素作用相似 ,均具有平喘及松驰气管平滑肌的作用。结论　国产班布特罗具有明显的平喘作用     

Trace element levels in drinking water and cognitive function among elderly Chinese

The relation between trace element levels in drinking water and cognitive function was investigated in a population-based study of elderly residents (n = 1,016) in rural China in 1996-1997. Cognitive function was measured using a Chinese translation of the Community Screening Interview for Dementia. A mixed effects model was used to evaluate the effect of each of the elements on cognitive function while adjusting for age, sex, and educational level. Several of the elements examined had a significant effect on cognitive function when they were assessed in a univariate context. However, after adjustment for other elements, many of these results were not significant. There was a significant quadratic effect for calcium and a significant zinc-cadmium interaction. Cognitive function increased with calcium level up to a certain point and then decreased as calcium continued to increase. Zinc showed a positive relation with cognitive function at low cadmium levels but a negative relation at high levels.     

EXPRESSION OF EBV LATENT MEMBRANE PROTEIN IN ESOPHAGEAL CARCINOMA AND PARA-CANCEROUS MUCOSA

ＥＸＰＲＥＳＳＩＯＮＯＦＥＢＶＬＡＴＥＮＴＭＥＭＢＲＡＮＥＰＲＯＴＥＩＮＩＮＥＳＯＰＨＡＧＥＡＬＣＡＲＣＩＮＯＭＡＡＮＤＰＡＲＡＣＡＮＣＥＲＯＵＳＭＵＣＯＳＡＷｕＭｉｎｇｙａｏ吴名耀ＬｉａｎｇＹｉｎｇｒｕｉ梁英锐ＷｕＸｉａｎｙｉｎｇ吴贤英Ｄｅｐａｒ...