Effects of MEK on kinetics ofn-hexane metabolites in serum

The neurotoxicity ofn-hexane is thought to be caused ultimately by 2,5-hexanedione (2,5-HD), one of then-hexane metabolites. The potentiation ofn-hexane neurotoxicity by co-exposure with MEK, therefore, is suspected to be related to kinetics of 2,5-HD in blood. To clarify the kinetics ofn-hexane metabolites in the mixed exposure ofn-hexane and MEK, rats were exposed to 2000 ppmn-hexane or a mixture of 2000 ppmn-hexane and 2000 ppm MEK, and the time courses of serumn-hexane metabolites were determined. 2,5-HD in serum increased until 2 h after the end of exposure, when serum 2,5-HD concentration reached a peak of 16.35 g/ml in then-hexane-alone group. In contrast, 2,5-HD in the mixed exposure group increased much more slowly during and after exposure than in then-hexane-alone group. It reached a peak of 2.12 g/ml at 8 h after the end of exposure. Serum MBK, a precursor of 2,5-HD in the co-exposure group, was about half in then-hexane-alone group during exposure. However, MBK decreased more slowly in the co-exposure group than in then-hexane-alone group after the end of the exposure. The results suggest that co-exposed MEK might inhibit oxidation ofn-hexane and decrease clearance ofn-hexane metabolites. Co-exposed MEK did not increase serum 2,5-HD, which was considered a main neurotoxic metabolite. Therefore the enhancement of neurotoxicity could not be attributed to increased serum 2,5-HD in the co-exposed group. The mechanism of enhancement of neurotoxicity ofn-hexane by MEK should be studied further.     

Tumor cell adhesion to frozen lymph node sections — a correlate of lymphatic metastasis in breast carcinoma models of human and rat origin

Summary The role of tumor cell adhesion in lymphatic metastasis of breast cancer was investigatedin vitro using a rat mammary carcinoma model of four cell lines with different metastatic phenotypes, two human breast cancer cell lines, and cryostast sections of normal rat or human lymph nodes, respectively. A positive correlation was found between the adhesion levels obtained with three metastatic rat mammary cell lines (TMT-081 > MT-100M & TMT-50) and a non-metastatic line MT-W9B, the latter being 3–4 fold less adhesive to the lymph node sections than the metastatic tumors. This selective adhesion was specific, as it was not found with cryostat sections of rat liver and brain. Enzyme assays indicated that cell surface glycoproteins bearing terminal -galactoside residues were involved in the adhesion of the rat tumors.Adhesion of the human breast carcinoma cells Hs578T to sections of human lymph nodes was significantly higher than that of the normal breast epithelial cell line Hs578Bst, and comparable to adhesion of a second breast carcinoma line, MCF-7. Moreover, Hs578T cells isolated from regional lymph nodes of tumor-bearing nude mice were significantly more adhesive to human lymph node sections than the parental line.Adhesion of both human and rat tumors could be partially blocked by the addition of the synthetic peptide GRGDSPK and by antibodies directed to the 1 chain of integrin, suggesting that an integrin receptor may played a role in the adhesion. The results suggest that tumor cell adhesion to cryostat sections of lymph nodes is a correlate of the malignant phenotype in mammary tumors of diverse origins, and could be used to delineate the adhesion factors mediating lymphatic metastasis.     

神经移植端侧缝合颈5/7神经根与上干桥接治疗产瘫

目的：探讨一种不影响残存神经自行恢复的产瘫臂丛神经修复新方法。方法：将上干损伤部位行松解,不切除神经瘤,将其近端的颈5或颈7神经根和神经瘤远端的臂丛上干的神经束膜切开窗口,取颈丛皮支或前臂外侧皮神经前成多段（一般每段长约2．0－2．5cm）,两端分别与颈5神经根和上干的神经束膜行端侧缝合,结果：8例患儿经术后1－11年（平均3年）的随访,4例的三角肌和肱二头肌骨力达4级和4^-级,4例达3例。3例后期进行了肩关节松解和旋前圆肌肌腱切断,结论：该方法既提供了可使损伤近端颈5神经根的新生纤维生长至上干的神经通道,又未阻断神经瘤内残存神经纤维的自行恢复,是治疗产瘫特别是Tassin2型的新术式。     

Apolipoprotein E polymorphism in the early onset of coronary heart disease

Objective To assess the relationship between apolipoprotein E (apoE) polymorphism and the early onset of coronary heart disease (CHD) and the effect of apoE on lipids and lipoproteins in healthy Chinese subjects. Methods Sixty-eight patients with CHD younger than 55 years (CHD1), 136 patients with CHD older than 65 years (CHD2), and 136 healthy subjects were enrolled, and their plasma levels of triglyceride (TG), total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C) were determined. The apoE genotypes were identified by polymerase chain reaction-restriction fragment length polymorphism.Results apoE 3/4 genotype and E4 allele frequency in the CHD1 group were higher than those in the CHD2 group and healthy subjects, while no differences were found between CHD2 and healthy subjects. Meanwhile, the plasma levels of TC and low density lipoprotein cholesterol (LDL-C) were higher in the CHD2 group than in both CHD1 group and healthy subjects.Each apoE isoprotein has variable TC and LDL-C levels that is E2 (E2/2+E2/3)＜E3(E3/3)<E4(E4/4+E3/4). Conclusion apoE is one of the genetic factors that affect TC and LDL-C levels, and apoE 4 has a very close relation to CHD, suggesting that apoE 4 is an independent genetic factor of the early onset of CHD.     

渤海鱼类和头足类异尖科线虫幼虫感染情况调查

[目的 ]调查渤海鱼类和头足类异尖科线虫幼虫感染情况 .[方法 ]对渤海 2 5种鱼 2 90尾和 3种头足类 10 8尾进行剖检 .[结果 ]发现 19种鱼 15 6尾和 1种头足类 8尾感染异尖科线虫幼虫 6种 ,计73 2 7条 .从 15种鱼 (N =191)中的 12 1尾 ( 63 4 % )和一种头足类 (N =5 4 )中的 8尾 ( 14 8% )体内检出简单异尖线虫幼虫 5 992条 ,占总数的 81 8% ,4种鱼是本幼虫的新发现宿主 .其余 13 3 5条幼虫中 ,15 4( 2 1% )条为鲔蛔线虫B型幼虫 ,采自 4种鱼 2 3尾 ;10 13 ( 13 8% )条为鲔蛔线虫C型幼虫 ,采自 13种鱼79尾 ;164( 2 2 % )条为宫脂线虫中国V型幼虫 ,采自 4种 2 0尾鱼 ;2种鱼感染针蛔虫幼虫 3条 ;仅发现 1条伪新地蛔虫幼虫 .     

四乙基胺抑制蟾酥的强心效应

[目的]观察蟾酥对离体蟾蜍心脏收缩运动的影响和各种受体阻断剂、钾通道阻断剂对这种效应的影响。[方法]将离体蟾蜍心脏收缩运动用张力换能器转换成电信号,通过Doctor-95 Super Lab软件系统在电脑上连续记录心率和收缩力的变化,并打印成曲线。[结果]取自蟾蜍同体耳后腺的蟾酥对离体蟾蜍心脏收缩运动有增强作用。M受体阻断剂阿托品（0.5g/L)和β受体阻断剂心得安（0.01g/L)不能阻断蟾酥对离体蟾蜍心脏收缩运动的增强作用,而α受体阻断剂酚妥拉明（0.5g/L)、非选择性钾通道阻断剂四乙基胺（10mmol/L)则明显抑制蟾酥对离体蟾蜍心脏收缩运动的增强作用。[结论]蟾酥是通过α受体作用于钾通道而增强离体蟾蜍心脏收缩运动。     

多重聚合酶链反应检测食品中致病性小肠结肠炎耶尔森菌和伤寒沙门氏菌

[目的 ]快速准确地检测致病性小肠结肠炎耶尔森菌和伤寒沙门氏菌 .[方法 ]根据小肠结肠炎耶尔森菌的ail基因和ST的H1 d基因顺序设计二对引物 ,通过聚合酶链反应检测食品中的小肠结肠炎耶尔森菌和伤寒沙门氏菌 ,扩增产物经电泳 ,分别出现与已知阳性对照细菌条带大小一致的 170和 4 5 8bp的ail和H1 d基因片断的条带时即判定该样品为阳性 .[结果和结论 ]本法特异性强、灵敏度高 ,能在60h内出结果 ,适用于食品中小肠结肠炎耶尔森菌和伤寒沙门氏菌的快速检验 .     

外伤性白内障人工晶状体植入术临床观察

目的 评价外伤性白内障人工晶体植入的疗效及问题。方法 对56例外伤性白内障人工晶体植入术后进行回顾性研究。结果 术后矫正视力≥0.5者48眼,占85.7%;0.1-0.4者6眼,占10.7%;0.1以下者2眼,占3.6%。结论 利用显微手术方法,使用粘弹剂,控制眼内炎症,选择好手术时机,可使手术效果满意。     

原发性女性生殖器恶性黑色素瘤16例分析

目的：探讨原发性女性生殖器恶性黑色素瘤的临床病理特点及合理的治疗方法。方法：对16例原发性女性生殖器恶性黑色素瘤的临床资料进行回顾性分析。结果：发生于外阴9例,阴道5例,子宫颈2例。全部病例均行手术加化疗综合治疗,行区域淋巴结清扫11例,4例有转移,转移率36.3％。存活＜2年8例,≥2年8例,其中≥5年仅2例。结论：原发性女性生殖器恶性黑色素瘤预后差,行根治手术辅化疗和免疫治疗,可望提高生存期。     

慢性丙肝患者抗病毒治疗前后血清IL-18、IL-10、sIL-2R、TNF-α水平变化的临床观察

目的 探讨IL－18、IL－10、sIL-2R、TNF－α在慢性丙型肝炎发病中的作用,观察干扰素抗病毒治疗对于上述细胞因子水平的影响。方法 酶联免疫吸附法（ELISA）检测10例正常人、24例丙型肝炎病毒携带者及27例慢性丙肝患者（包括干扰素治疗前、后）血清中上述细胞因子水平。结果 慢性丙肝患者血清中上述细胞因子显著高于正常对照组（P＜0．05）及丙肝病毒携带者组（P＜0．05）,且其值与谷丙转氨酶（GPT）呈显著正相关;经干扰素治疗后上述细胞因子水平均明显降低,HCV－RNA未阴转组治疗前血清中sIL-2R、IL－10水平明显高于HCV－RNA阴转组（P＜0．05）。结论 上述细胞因子共同参与慢性丙型肝炎的发病,并可用于评价干扰素对于机体免疫状态的影响;且sIL－2、IL－10对预测抗病毒疗效有重要意义。