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61.
浙江黑麂栖息地评价及保护对策 总被引:1,自引:0,他引:1
运用地理信息系统技术,在分析黑麂栖息地的地形、植被、水系和人为干扰等地理特征的基础上,系统研究九龙山和古田山自然保护区黑麂栖息地分布、栖息地质量与空间格局。结果表明,在九龙山自然保护区有黑麂潜在栖息地3172.6hm^2,由于人类活动的影响导致栖息地丧失501.5hm^2,目前尚存的黑麂适宜栖息地2671.1hm^2。它们主要分布于上寮坑、九龙山、内北坪、外九龙和大岩前附近区域。古田山自然保护区有黑麂潜在栖息地4635.75hm^2,在人类活动影响下丧失栖息地1118.11hm^2,目前尚存的黑麂适宜栖息地3517.64hm^2。它们主要分布于青尖、古田山、巧观尖、催顶尖附近区域。目前九龙山和古田山自然保护区内的黑麂栖息地基本上处于多斑块破碎化状态。为了使黑麂能得到更好的保护,对这两个研究区域黑麂栖息地的恢复和重建工作亟待加强。 相似文献
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63.
Shixing Yang Yumin He Ju Zhang Dianqi Zhang Yan Wang Xiang Lu Xiaochun Wang Quan Shen Likai Ji Hongyan Lu Wen Zhang 《中国病毒学》2022,37(1):82-93
Diarrhea is the third leading cause of death in developing countries in children under the age of five. About half a million children die of diarrhea every year, most of which in developing countries. Viruses are the main pathogen of diarrhea. In China, the fecal virome of children with diarrhea has been rarely studied. Using an unbiased viral metagenomics approach, we analyzed the fecal virome in children with diarrhea. Many DNA or RNA viruses associated with diarrhea identified in those fecal samples were mainly from six families of Adenoviridae, Astroviridae, Caliciviridae, Parvoviridae, Picornaviridae, and Reoviridae. Among them, the family of Caliciviridae accounts for the largest proportion of 78.42%, following with Adenoviridae (8.94%) and Picornaviridae (8.36%). In addition to those diarrhea-related viruses that have already been confirmed to cause human diarrhea, the viruses not associated with diarrhea were also identified including anellovirus and picobirnavirus. This study increased our understanding of diarrheic children fecal virome and provided valuable information for the prevention and treatment of viral diarrhea in this area. 相似文献
64.
Lei Yang Lingqian Tian Leshan Li Qiuhong Liu Xiang Guo Yuan Zhou Rongjuan Pei Xinwen Chen Yun Wang 《中国病毒学》2022,37(3):341-347
Transformation-associated recombination (TAR) has been widely used to assemble large DNA constructs. One of the significant obstacles hindering assembly efficiency is the presence of error-prone DNA repair pathways in yeast, which results in vector backbone recircularization or illegitimate recombination products. To increase TAR assembly efficiency, we prepared a dual-selective TAR vector, pGFCS, by adding a PADH1-URA3 cassette to a previously described yeast-bacteria shuttle vector, pGF, harboring a PHIS3-HIS3 cassette as a positive selection marker. This new cassette works as a negative selection marker to ensure that yeast harboring a recircularized vector cannot propagate in the presence of 5-fluoroorotic acid. To prevent pGFCS bearing ura3 from recombining with endogenous ura3-52 in the yeast genome, a highly transformable Saccharomyces cerevisiae strain, VL6-48B, was prepared by chromosomal substitution of ura3-52 with a transgene conferring resistance to blasticidin. A 55-kb genomic fragment of monkeypox virus encompassing primary detection targets for quantitative PCR was assembled by TAR using pGFCS in VL6-48B. The pGFCS-mediated TAR assembly showed a zero rate of vector recircularization and an average correct assembly yield of 79% indicating that the dual-selection strategy provides an efficient approach to optimizing TAR assembly. 相似文献
65.
Dan Wu Zhen-yu Qian Tingting Guo Wenyan Tang Yi Xiang Heng Zheng 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(28):2911-2915
A rapid, sensitive and simple high performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) method was developed for determination of cefazedone in human plasma using metronidazole as internal standard (IS). The chromatographic separation was achieved on an Ultimate XB-CN column (2.1 mm × 150 mm, 5 μm) with an isocratic mobile phase of acetonitrile and 20 mM ammonium acetate in 0.1% formic acid in water (15:85, v/v). Detection was performed using electrospray ionization in positive ion multiple reaction-monitoring mode (SRM), monitoring the transitions m/z 548.2 → 344.1 for cefazedone and m/z 172.2 → 128.1 for IS. Calibration curves were linear over a wide range of 0.20–401.12 μg/mL for cefazedone in plasma. The lower limit of quantification (LLOQ) was 0.20 μg/mL. The intra- and inter-day precisions were less than 7.2%. The average recovery of cefazedone was 90.8–91.0%. The validated method was successfully applied to the pharmacokinetic study of cefazedone in Chinese healthy volunteers following intravenous (IV) administration of 500, 1000 and 2000 mg cefazedone injection. 相似文献
66.
【目的】BhSGAMP-1 是迟眼蕈蚊唾液腺抗菌肽,为了能够更好的了解其分子特性,我们将其表达、纯化并进行了活性测定。【方法】依据大肠杆菌稀有密码子设计并合成了抗菌肽基因 BhSGAMP-1-S,以 pMAL-c2X 作为表达载体在大肠杆菌 TB1 中进行融合表达,融合蛋白通过麦芽糖亲和层析柱进行纯化,获得的融合蛋白经肠激酶切割后,混合物通过分子筛凝胶层析和反相高效液相色谱来获得单体重组抗菌肽 BhSGAMP-1-S,对获得的抗菌肽进行活性测定。【结果】在最优的表达条件下融合蛋白以可溶的形式表达,100 mL 诱导菌液经多步纯化后可得 0. 38 mg 的重组抗菌肽 BhSGAMP-1-S,抑菌活性测定表明所获得的抗菌肽对部分测试革兰氏阳性细菌、革兰氏阴性细菌和真菌有较强的抑菌活性。【结论】本研究第一次成功的在大肠杆菌中诱导表达了修饰合成的抗菌肽 BhSGAMP-1-S,纯化后的抗菌肽具有很好的抑菌活性,这为进一步研究和应用奠定了基础。 相似文献
67.
The paper reports 13 species from Yaoluoping National Nature Reserve,Anhui,China,including a new species and a new subspecies,Tipula (Emodotipula) alexanderi Men,sp.nov.and Nephrotoma impigra anqingensis Men,subsp.nov.The female of Libnotes (Libnotes) pseudonohirai Men,2015 is described and illustrated for the first time.The males of Holorusia henana Yang,1999 and Tipula (Vestiplex)jiangi Yang & Yang,1991 are redescribed and illustrated with new morphological characters.A key to all species is provided. 相似文献
68.
苯酚的生物降解基因组成及其调控机制 总被引:15,自引:1,他引:15
苯酚的生物降解受多组分的降解基因控制,形成邻位和间位等不同的代谢途径.结合部分实验结果,介绍了邻位和间位代谢系统的基因组成及其作用机制等方面的研究进展,讨论了调节基因在苯酚降解菌中的作用和不同因素对苯酚降解的影响. 相似文献
69.
70.
We used the Mandarin Chinese version of the Camberwell Family Interview (CFI) to measure the components of expressed emotion among relatives of schizophrenic patients in urban and rural areas of Chengdu, China. The reliability and validity of the Chinese version of the CFI was examined. Seventy-one patients and their key relatives were included in the study. The results showed that high interrater reliabilities were found for the Chinese version of CFI. The proportion of relatives in our sample rated as high-EE was 28.2%, and the Chengdu relatives expressed significantly fewer critical comments (CCs) and less emotional overinvolvement (EOI) than respondents in other similar studies in the West. Within the Chengdu sample, city dwellers were significantly more expressive than villagers expressing warmth, positive remarks, and EOI (p<0.05). The results of this study could indicate the impact of cultural and ethnic differences and geographical location on EE. 相似文献