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91.
旋毛虫南阳猪体分离株的生物学特性研究 总被引:1,自引:0,他引:1
观测了旋毛虫南阳猪体分离株的形态大小,测定了其在小鼠和猪体中的繁殖力指数、雌虫体外产新生幼虫的能力和对低温的耐受性。测得该虫株雄成虫、雌成虫和发育充分的肌幼虫的长宽度分别为(1.415±0.164)mm×(0.048±0.014)mm,(2.627±0.246)mm×(0.056±0.018)mm和(1.112±0.185)mm×(0.038±0.013)mm;其在昆明小白鼠和三元杂交猪体中的繁殖力指数分别为(112.0±59.65)和142.5;平均每条雌虫体外产新生幼虫(56.76±5.13)条;在猪肉中的感染性肌幼虫置-32℃36 h或-22℃60 h即全部死亡。结果表明,该旋毛虫南阳猪体分离株的上述生物学特性与猪旋毛虫(T.spiralis)的特性相似。 相似文献
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93.
京城地区木材业界针对目前木材制品供销情况越来越冷的现实,普遍认为今年的冬天将是京城地区木材市场近些年来最为难过的季节。 相似文献
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AIM and METHODS: to elucidater the effect of poly(ADP-ribose) polymerase(PARP) on tracheal hyperreactivity of guinea - pig induced by peroxynitrite, the responses of guinea pig tracheas to histamine af- ter incubation with peroxynitrite in the absence and presence of 3 - aminobenzamide(3 - AB), a highly selective inhibitor for PARP, were observed in vitro. RESULTS: The exposure of tracheal strips to peroxynitrite led to epithelial damage and hyperreacitivity to histamine, both of which were reversed by 3 - AB(lmmol/L or 5mmol/L), whereas incubation of tracheal strips with 3 - AB(5mmol/L) had no effect on the reponses. CONCLUSION: PARP is involved in the epithelial damage and hyperreactivity of guinea - pig tracheas induced by peroxynitrite. The results suggested that inhibition of excessive activation of PARP may represent a novel strategy for the prevention and therapy of airway hyperreactivity in asthma. 相似文献
96.
AIM: To explore the effect of EBV infection on growth and apoptosis of nasopharyngeal carcinoma(NPC) cell line.METHODS: NPC cell line CNE1 was directly infected by Epstein Barr virus (EBV). The expression of EBV-latent membrane protein 1 (EBV-LMP1) and bcl-2 were detected by immunohistochemistry method (LSAB). The growth of NPC cells was identified by MTT method. Apoptotic carcinoma cells were detected by flow cytometry analysis and the terminal deoxynucletidyl transferase-medicated dUTP-biotin nick end labeling (TUNEL) methods. RESULTS: EBV-LMP1 was positive in CNE1 infected by EBV(E-CNE1). Compared with CEN1, the growth of E-CNE1 apparently increased (P<0.01). No apoptotic carcinoma cells were detected and bcl-2 postive cells were 2%~3% respectively in 2 kinds of NPC cells.CONCLUSION: Growth of NPC cells is enhanced by EBV infection and EBV-LMP1 expression, but no influence on expression of bcl-2 and apoptosis of NPC cells. 相似文献
97.
YAN Xiao-cheng MU Wei-na QIANG Ye ZHAO Hui-chen SUN Qi YAO Xiao-min ZHANG Yu-chao LIU Yuan-tao 《园艺学报》2000,36(9):1661-1666
AIM To investigate the effects of cytochrome P450 (CYP450) epoxygenase/epoxyeicosatrienoic acid (EET) pathway on insulin resistance in obese mice, and to explore the possible mechanisms. METHODS High-fat diet-induced obesity model was established in C57BL/6Cnc mice, and the obese mice were randomly divided into 3 groups, including obesity group (treated with saline; n =10), EET group (treated with 11,12-EET; n =10) and EET inhibitor 14,15-epoxyeicosa-5(Z)-enoic acid (EEZE) group (n =10). Normal C57BL/6Cnc mice (n =10) treated with saline served as control. Protein expression of CYP2J2 (one of CYP450 epoxygenases) and hypoxia-inducible factor-1α (HIF-1α) was measured by Western blot. Vessel-like structure was detected by immunofluorescence staining. The serum levels of insulin, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and monocyte chemoattractant protein-1 (MCP-1) were measured by ELISA. RESULTS In obese mice, homeostasis model assessment of insulin resistance (HOMA-IR) values were increased, the protein level of CYP2J2 was reduced, and the protein level of HIF-1α was increased in adipose tissues as compared with the controls (P <0.05). The serum levels of MCP-1, IL-1β, IL-6 and TNF-α were also significantly increased in obese mice (P <0.05). After treatment with 11, 12-EET, the HOMA-IR values were decreased compared with vehicle-treated obese mice, HIF-1α expression levels were decreased in the adipose tissue, and the serum levels of MCP-1, IL-1β, IL-6 and TNF-α were reduced (P <0.05). Immunohistochemical results of adipose tissue from vehicle-treated obese mice showed a marked decrease in vessel-like structures (CD31-positive) compared with normal control mice (P <0.05). EET treatment significantly increased the newly formed vessel-like structures in the visceral adipose tissues of obese mice as compared with vehicle-treated obese mice (P <0.05). CONCLUSION High-fat diet-induced obesity and insulin resistance are closely related to the CYP450 pathway. Exogenous EETs effectively decrease obesity-induced insulin resistance possibly through pro-angiogenesis and attenuation of hypoxia and inflammation. 相似文献
98.
GUAN Cang-hai ZHAO Yu-qiao Guo Liang CHEN Yu-Zhu WANG Wei-Na JIANG Xing-ming 《园艺学报》2000,36(10):1908-1912
MNX1 antisense RNA 1 (MNX1-AS1) is a newly discovered long non-coding RNA (lncRNA), which is highly dysregulated in various carcinomas and its expression level is closely related to the overall survival and prognosis of patients. MNX1-AS1 regulates the occurrence and development of carcinomas by endogenous competitive adsorption of miRNA, regulating cell cycle, inducing epithelial mesenchymal transformation and activating multiple signaling pathways. The in-depth study of the carcinogenesis of MNX1-AS1 is useful for the early diagnosis, targeted therapy and prognostic assessment of relevant carcinomas. This article reviews the roles of MNX1-AS1 in malignant tumor. 相似文献
99.
大菱鲆致病性溶藻弧菌SR1的外膜蛋白及其抗原性分析 总被引:3,自引:0,他引:3
用十二烷基肌氨酸钠(Sarkosyl)抽提结合超速离心的方法提取了一株大菱鲆致病性溶藻弧菌(Vibrio alginolyticus)SR1和其他7株弧菌的外膜蛋白。通过SDS-PAGE图谱分析比较了这8株弧菌外膜蛋白的组成,结果表明,8株弧菌的外膜蛋白电泳一般可得到6-12条条带,其分子量多集中在65-106 kD和28-48 kD,其中36 kD的蛋白带为8株弧菌所共有。用兔抗SR1全菌血清进行Western-blot印迹显示,菌株SR1的外膜蛋白条带中有6条发生了阳性反应,其分子量分别为73 kD、48 kD4、5 kD3、9 kD、36 kD和32 kD。而其他7株弧菌的外膜蛋白与兔抗SR1血清也发生程度不等的阳性反应,这些阳性反应条带的分子量集中在65-73 kD、45-48 kD和36-41 kD之间,其中36 kD的外膜蛋白在8株弧菌中均出现明显的阳性反应,说明36 kD的外膜蛋白是这8株弧菌共有的特异性抗原。 相似文献
100.