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731.
LIU DingZhen ;WEI RongPing ;ZHANG GuiQuan ;YUAN Hong ;WANG ZhiPeng ;SUN Lixing ;ZHANG Jianxu ;ZHANG HeMin 《科学通报(英文版)》2008,53(18):2793-2800
Chemical communication plays an important role in kin selection and mate choice in mammals. The covariance of odor-genes of rodents has been documented and kinship odor has been proposed and termed, yet little is known of the relationship between genetic relatedness and chemical composition of kinship odors. Giant pandas (Ailuropoda melanoleuca) rely substantially on chemical communication to mediate their social interactions. To examine the relationship between genetic relatedness and compounds in the urine/anogenital gland secretions, we compared the similarities between genetic relatedness and the chemical profiles of anogenital gland secretions and urine via lineage construction and GC-MS (gas chromatography and mass spectrometry). We found that information about kinship odors was present only in the urine of male adults in the mating season but absent in the non-mating season. Adult females and all sub-adults did not have such kinship odors in either mating or non-mating season. Therefore, kinship odor in the panda was contingent on age, sex, and season. This is the first report about the condition-dependent expression of kinship odor, which may have a significant implication in the practice of panda conservation in relation to chemical communication and sexual selection. 相似文献
732.
Case Report: Adrenal myelolipoma within myxoid cortical adenoma associated with Conn's syndrome
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Hong-sheng LU Mei-fu GAN Han-song CHEN Shan-qiang HUANG 《浙江大学学报(自然科学英文版)》2008,9(6):500-505
The coexistence of myelolipoma within adrenal cortical adenoma is extremely rare, for both tumors present usually as separate entities. There are only 16 such cases reported worldwide. To the best of our knowledge, the case we reported here is the first one of myxoid adrenal cortical adenoma associated with myelolipoma reported. A 32-year-old Chinese woman with 4-year history of hypertension was presented in our study. Computed tomography (CT) of the abdomen showed a large heterogeneously-enhancing mass (4.5 cm in diameter) in the left suprarenal region. Clinical history and laboratory results suggest a metabolic disorder as Conn's syndrome. The patient underwent a left adrenalectomy, and a histopathological study confirmed the mass to be a myxoid adrenal cortical adenoma containing myelolipoma. The patient was postoperatively well and discharged uneventfully. In the present case report, we also discuss the etiology of simultaneous myelolipoma and adrenal adenoma associated with Conn's syndrome, and the methods of the diagnosis and differential diagnosis. 相似文献
733.
蛇目菊是重要的城市观赏花卉和珍贵的药用植物.本文采用常规的植物染色体制片技术对蛇目菊体细胞染色体数目进行统计,并对其核型进行了分析.结果表明:蛇目菊的染色体数目为2n=24;核型公式为2n=2x=24=20m 4sm,属于1B型.蛇目菊的染色体组总长度为14.60μm.因此希望通过本研究为探讨引进物种蛇目菊的生物多样性及其近缘的种间鉴定提供重要的细胞学理论依据. 相似文献
734.
735.
分析了旋风除尘器现用耐磨措施,提出了在旋风除尘器易磨部位设置料盒来抵抗磨损的新型耐磨技术通过现场试验研究证实,它可提高旋风除尘器的性能,并使其使用寿命延长5~10倍,具有良好的社会、经济效益图3,表3,参6 相似文献