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记述采自陕西秦岭的吉松叶蜂属Gilpinia Benson1新种-青扦吉松叶蜂G.wilsonae sp.n。该种昆虫青扦Picea wilsonii Mast.,一年发生两代,结茧过冬。新种的模式标本保存于西北林学院昆虫标本室。 相似文献
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Xiao‐dong Xia Zheng‐jie Xu Xiao‐guang Hu Cheng‐yun Wu Yuan‐rong Dai Lei Yang 《Cell biochemistry and function》2012,30(4):279-285
Nitric oxide (NO) is an important vascular modulator in the development of pulmonary hypertension. NO exerts its regulatory effect mainly by activating soluble guanylate cyclase (sGC) to synthesize cyclic guanosine monophosphate (cGMP). Exposure to hypoxia causes pulmonary hypertension. But in lung disease, hypoxia is commonly accompanied by hypercapnia. The aim of this study was to examine the changes of sGC enzyme activity and cGMP content in lung tissue, as well as the expression of inducible nitric oxide synthase (iNOS) and sGC in rat pulmonary artery after exposure to hypoxia and hypercapnia, and assess the role of iNOS–sGC–cGMP signal pathway in the development of hypoxic and hypercapnic pulmonary hypertension. Male Sprague–Dawley rats were exposed to hypoxia and hypercapnia for 4 weeks to establish model of chronic pulmonary hypertension. Weight‐matched rats exposed to normoxia served as control. After exposure to hypoxia and hypercapnia, mean pulmonary artery pressure, the ratio of right ventricle/left ventricle + septum, and the ratio of right ventricle/body weight were significantly increased. iNOS mRNA and protein levels were significantly increased, but sGC α1 mRNA and protein levels were significantly decreased in small pulmonary arteries of hypoxic and hypercapnic exposed rat. In addition, basal and stimulated sGC enzyme activity and cGMP content in lung tissue were significantly lower after exposure to hypoxia and hypercapnia. These results demonstrate that hypoxia and hypercapnia lead to the upregulation of iNOS expression, downregulation of sGC expression and activity, which then contribute to the development of pulmonary hypertension. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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