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1.
鳗鲡寄生伪指环虫(单殖吸虫)的危害性、生物学和治疗试验 总被引:7,自引:0,他引:7
本文研究了人工放养池内引起鳗鲡鳃病的寄生虫是秉伪指环虫和鳗鲡伪指环虫。影响秉伪指环虫纤毛幼虫孵化的因素,与温度和寄主粘液密切相关,而与光照可能无关。在实验室里,分别用药物处理带有病原体的鳗苗,表明:用0.3—0.5ppm90%,晶体敌百虫,可达全部杀灭病原体的良好效果,1%氯化钠长期药浴也有显著效果。 相似文献
2.
C. W. E. REDMAN S. E. CHAPMAN S. Y. CHAN E. J. BUXTON G. BLACKLEDGE D. M. LUESLEY† 《Cytopathology》1991,2(6):291-298
Peritoneal lavage fluid cytology was performed in 87 out-patients with histologically proven epithelial ovarian cancer undergoing primary management. A total of 246 peritoneal lavages were attempted, usually with temporary cannulae (n = 229). From these, 184 samples were obtained, of which 156 (85%) were suitable for cytological analysis. The sensitivity of peritoneal lavage fluid cytology in 67 patients with known residual disease was 57% whereas serum CA 125 levels were elevated in 58 (87%). Pre- and post-treatment peritoneal lavage fluid cytology had prognostic value, but this was less than that of serum CA 125 measurements. 相似文献
3.
稻飞虱是缅甸水稻种植区常见且分布广泛的一类害虫,可造成农作物不同程度的减产.稻飞虱的爆发与高产品种的大规模推广种植具有一致性,同时其种群变化也与天气条件有关.近年来,缅甸中部部分省份稻飞虱大量孳生,在一定程度上,这与氮肥施用水平有关.雨季稻飞虱种群增加,7月和8月为高峰期.在缅甸,主要通过培育抗虫、抗旱、抗逆等水稻品种来防控稻飞虱.同时用诱虫灯进行早期入侵的虫源的监测,必要时,采用化学杀虫剂防治.缅甸部分农场还采用了病虫害综合管理系统(IPM),以建立健康、安全、可调节的水稻生态系统及可持续的病虫害管理. 相似文献
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- 1 Evidence from the literature, interviews, market surveys, general rapid field surveys and camera trapping was reviewed to infer the regional status of 33 recorded carnivores in South China (Guangxi, Guangdong, Hainan, Hong Kong and Macau).
- 2 The carnivore fauna in South China is among the most depleted for any continental area in the world.
- 3 The tiger Panthera tigris, leopard Panthera pardus, grey wolf Canis lupus and binturong Arctictis binturong are probably extirpated.
- 4 The dhole Cuon alpinus, Asiatic golden cat Catopuma temmincki and clouded leopard Neofelis nebulosa are at great risk of regional extirpation, as are the more ecologically adaptable red fox Vulpes vulpes, raccoon dog Nyctereutes procyonoides, Asian badger Meles leucurus, Eurasian otter Lutra lutra, Oriental small‐clawed otter Aonyx cinereus and large Indian civet Viverra zibetha.
- 5 Though more widely reported, the Asiatic black bear Ursus thibetanus, yellow‐throated marten Martes flavigula, hog badger Arctonyx collaris and Siberian weasel Mustela sibirica are at regional risk.
- 6 The status of the Burmese ferret‐badger Melogale personata, stripe‐backed weasel Mustela strigidorsa, smooth‐coated otter Lutrogale perspicillata, large‐spotted civet Viverra megaspila and Owston's palm civet Chrotogale owstoni is uncertain due to inadequate information.
- 7 Five carnivore species – the Chinese ferret‐badger Melogale moschata, masked palm civet Paguma larvata, yellow‐bellied weasel Mustela kathiah, small Indian civet Viverricula indica and leopard cat Prionailurus bengalensis– are relatively secure (though not common) in the region, along with the Asian palm civet Paradoxurus hermaphroditus and the Javan mongoose Herpestes javanicus in some areas, while the spotted linsang Prionodon pardicolor and crab‐eating mongoose Herpestes urva may have been under‐reported.
- 8 The main threats have been habitat destruction and unsustainable exploitation. Only in Hong Kong, where enforcement of protection legislation has been stronger, are the surviving carnivore species easily encountered.
- 9 Improved enforcement and monitoring are essential to retaining the remainder of South China's carnivores. Support could be boosted by conservation education and better research.
6.
<正>翼手目为哺乳动物中的第二大目,中国的翼手目多样性也在不断更新,Smith和解焱(2009)统计中国翼手目118种,蒋志刚等(2015)则认为中国翼手目有7科34属134种。广东省翼手目有6科24属55种(邹发生和叶冠锋,2016),此后也仍陆续有新纪录,如长指鼠耳蝠(Myotis longipes)(张琴等,2017)、卡氏伏翼(Hypsugo cadornae)(Xie et al., 2021);我们前期对澳门翼手目的调查,发现5科8属10种(黄继展等,2013)。 相似文献
7.
延胡索的化学成分研究(英文) 总被引:2,自引:0,他引:2
采用现代分离技术和方法,从延胡索根茎中分离得到17个化合物,通过波谱分析鉴定其结构。包括11个生物碱类化合物,二氢白屈菜红碱(1)、去氢紫堇碱(2)、四氢非洲防己胺(3)、异紫堇球碱(4)、紫堇碱(5)、四氢黄连碱(6)、药根碱(7)、黄连碱(8)、小檗碱(12)、巴马汀(13)和延胡索乙素(14);2个蒽醌类化合物,大黄素(9)和大黄素甲醚(10);1个三萜类化合物,即3β-羟基-齐墩果烷-111,3(18)-二烯-28-酸(11)和3个甾醇类化合物,豆甾醇(15)、β-谷甾醇(16)和胡萝卜苷(17)。其中,化合物9~11首次从该属植物中分离得到,1首次从该种中分离得到。 相似文献
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DONG‐SEOK KIM SOOK‐YOUNG KIM SEONG‐JOON MOON JIN‐HO CHUNG KYU‐HAN KIM KWANG‐HYUN CHO KYOUNG‐CHAN PARK 《Pigment cell & melanoma research》2001,14(2):110-115
Ceramide is a bioactive sphingolipid that mediates a variety of cell functions. However, the effects of ceramide on cell growth and the melanogenesis of melanocytes are not known. In the present study, we investigated the actions of cell‐permeable ceramide and its possible role in the signaling pathway of a spontaneously immortalized mouse melanocyte cell line, Mel‐Ab. Our results show that C2‐ceramide inhibits DNA synthesis in Mel‐Ab cells and G361 human melanoma cells in a dose‐dependent manner. Cell cycle analysis confirmed the inhibition of DNA synthesis by a reduction in the S phase. To investigate the ceramide signaling pathway, we studied whether C2‐ceramide is able to influence extracellular signal‐regulated kinase (ERK) and/or Akt/protein kinase B (PKB) activation. We demonstrated that phosphorylated Akt/PKB is decreased by C2‐ceramide, whereas phosphorylated ERK was only slightly affected. Therefore, the C2‐ceramide‐induced inactivation of Akt/PKB may be closely related to the reduced cell proliferation of Mel‐Ab cells. Furthermore, we assessed the effects of C2‐ceramide on the pigmentation of Mel‐Ab cells. The results obtained showed that the melanin content of cells was significantly reduced by C2‐ceramide at concentrations in the range of 1–10 μM, and that the pigmentation‐inhibiting effect of C2‐ceramide is much greater than that of kojic acid at 1–100 μM. In addition, we found that the activity of tyrosinase is reduced by C2‐ceramide treatment. Our results demonstrate that C2‐ceramide reduces the pigmentation of Mel‐Ab cells by inhibiting tyrosinase activity. 相似文献