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一百余年前,人类就开始了相对系统的野生动物调查。目前已经建立了成熟的方法体系,并制定了相应的调查规范。最近几十年来,我国科研人员进行了大量的野生动物调查。但是,当前我国的野外调查规范还不够细致,调查者在调查时缺乏必要的约束,导致调查数据不规范、不可靠,很多重要信息缺失。突出问题有:样线信息不全,只有起点和终点的经纬度,没有自动记录的详细样线信息(如每秒记录一次的连续点位信息,含经纬度和时间);动物位点信息缺乏可信度指标(如距观测者的距离);调查时间不合理;调查地点的空间取样不均衡;记录的标准化不够(如每个观测点的观测时长不确定)等等。对此,我们参考国际通用的调查规范,提出了一些简单易行的调查要点,以便提高野外调查数据的质量。另外,我们提倡野外记录的无纸化,充分利用现有的手机应用软件(APP)和模型工具提高野外记录以及后期数据处理的效率。最后,我们提议建立固定的中国生物多样性监测样线体系,以便消除每年调查时空间取样的不确定性,更好地量化野生动物的时间动态,为野生动物的保护和管理提供依据。 相似文献
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Rick A. Brenneman Robert C. Barber Ryan M. Huebinger Julie A. Sommer Edward E. LouisJr. 《Conservation Genetics》2007,8(4):1017-1020
The Komodo monitor (Varanus komodoensis) is a classic example of a species that has been fragmented into small isolated populations over a limited range. This species,
classified as endangered under Appendix I of the Convention on the International Trade of Endangered Species. We describe
10 novel species-specific microsatellite loci characterized in representatives from three of the endemic island populations.
One locus, 12HDZ820 appears to be fixed in one population at an allele size not found in the other two. This microsatellite
suite should be helpful in augmenting the marker selection currently available for Komodo Monitor population studies. 相似文献
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Sara Jiménez-Puertas David Sánchez-Artuñedo Marcelino Hermida-López 《Reports of Practical Oncology and Radiotherapy》2018,23(2):121-125
Aim
This work aims to achieve the highest possible monitor units (MU) reduction using the MU Objective tool included in the Eclipse treatment planning system, while preserving the plan quality.Background
The treatment planning system Eclipse (Varian Medical Systems, Palo Alto, CA) includes a control mechanism for the number of monitor units of volumetric modulated arc therapy (VMAT) plans, named the MU Objective tool.Material and methods
Forty prostate plans, 20 gynecological plans and 20 head and neck plans designed with VMAT were retrospectively studied. Each plan (base plan) was optimized without using the MU Objective tool, and it was re-optimized with different values of the Maximum MU (MaxMU) parameter of the MU Objective tool. MU differences were analyzed with a paired samples t-test and changes in plan quality were assessed with a set of parameters for OARs and PTVs.Results
The average relative MU difference considering all treatment sites, was the highest when MaxMU = 400 (?4.2%, p < 0.001). For prostate plans, the lowest was obtained (?3.7%, p < 0.001). For head and neck plans was ?7.3% (p < 0.001) and for gynecological plans was 7.0% (p = 0.002). Although similar MU reductions were observed for both sites, for some gynecological plans maximum differences were greater than 10%. All the assessed parameters for PTVs and OARs sparing showed average differences below 2%.Conclusion
For the three studied clinical sites, establishing MaxMU = 400 led to the optimum MU reduction, maintaining the original dose distribution and dosimetric parameters practically unaltered. 相似文献5.
2000年广州地区常见病原菌耐药性监测 总被引:10,自引:0,他引:10
叶惠芬 《中国微生态学杂志》2001,13(6):346-348
目的:对广州地区临床分离菌进行耐药性监测,为临床合理用药提供依据。方法:采用纸片扩散法进行药敏试验,用whonet软件进行统计和分析。结果:耐甲氧床西林的金黄色葡萄球菌和凝固酶阴性葡萄球菌分别占50.8%和79.1%,未发现耐万古霉素的葡萄球菌,大肠埃希菌和克雷伯菌属未发现耐亚胺培南,产超广谱β-内酰胺酶的发生率为36.4%和31.7%,肠杆菌属、不动杆菌属对第三代头孢菌素的耐药率较高,铜绿假单胞菌对头孢他啶和亚胺培南仍较敏感。结论:了解细菌耐药的最新动态,对临床合理用药具有重要意义。 相似文献
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The defined estrone glucuronide-lysozyme conjugate E3, that is acylated solely at K33, was used as a probe for the steric requirements of the active site cleft of chicken type lysozymes. When the immune complex was formed with an anti-estrone glucuronide antiserum, the rate of lysis of the E3 conjugate with the large bacterial substrate Micrococcus lysodeikticus was inhibited by over 90%. However, when the small hexamer of N-acetyl glucosamine was used as the substrate, the rate of hydrolysis by the immune complex was accelerated by 350% compared with the control rate. Thus, inhibition by the anti-estrone glucuronide cannot be caused simply by steric occlusion of the active site. Other factor(s) in the immune complex activate the hydrolysis reaction, most likely by favouring the conformations that lead to the transition state. 相似文献
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The Rhizobium meliloti
dctA gene encodes the C4-dicarboxylate permease which mediates uptake of C4-dicarboxylates, both in free-living and symbiotic cells. Based on the hydrophobicity of the DctA protein, 12 putative membrane spanning regions were predicted. The membrane topology was further analysed by isolating in vivo fusions of DctA to Escherichia coli alkaline phosphatase (PhoA) and E. coli -galactosidase (LacZ). Of 10 different fusions 7 indicated a periplasmic and 3 a cytoplasmic location of the corresponding region of the DctA protein. From these data a two-dimensional model of DctA was constructed which comprised twelve transmembrane -helices with the amino-terminus and the carboxy-terminus located in the cytoplasm. In addition, four conserved amino acid motifs present in many eukaryotic and prokaryotic transport proteins were observed. 相似文献
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J. K. Pell A. D. P. Barker S. J. Clark N. Wilding P. G. Alderson 《Biocontrol Science and Technology》1998,8(1):13-21
A novel piece of equipment, the sporulation monitor, is described for the comparison of conidia production from mycelia receiving diVerent formulation and storage treatments. This equipment was used to compare the viability of Zoophthora radicans mycelial samples treated either with 10% maltose solution or with distilled water before drying and storage for 0-12 weeks at 4oC. Freshly dried maltose-treated mycelial mat samples produced significantly more conidia for a significantly longer time than distilled water-treated mat samples of the same age. Very few conidia were produced from mats in either treatment after storage for 4 weeks or longer. There were great diVerences in conidia production from mycelial mat samples produced in diVerent fermenter runs. These results are discussed in relation to the potential for the use of dried mycelia in biological control programmes. 相似文献
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Loop-mediated isothermal amplification (LAMP) yields a large amount of DNA, as well as magnesium pyrophosphate precipitate, causing a decrease in ionic strength that can be measured with a conductivity meter. There is a clear relationship between the conductivity of the LAMP mixture solution and the duration of biochemical reaction. Moreover, there is also a clear relationship between the change in conductivity and the amount of initial template DNA over the range of 0.08 to 3.2 ng. These results demonstrate the feasibility not only for detecting the LAMP product qualitatively but also for real-time monitoring the biochemical reaction progression quantitatively using conductivity measurements. 相似文献
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目的:分析我院住院患者医院感染的发病特点和危险因素。方法:利用前瞻性监测和回顾性分析方法对2012年1~3月我院收治的6719例住院患者中发生医院感染的病例进行调查分析。结果:6719例住院患者发生医院感染145例,感染率2.16%;感染部位以呼吸系统为首(59.3%),其余依次为为胃肠道(17.2%)和泌尿道(11.7%);ICU的感染率最高,为22.0%,其次为外科系统(4.03%)和内科系统(1.71%)。病原学检测送检率为51.0%,阳性率为78.3%,共检出118株病原菌,其中革兰氏阴性菌占57.6%,真菌占22.9%,革兰氏阳性菌占17.8%。导致院内感染的危险因素中最常见的为放疗化疗(31.0%)、气管切开(15.9%)、导尿插管(17.9%)。结论:加强医务人员的感控意识,强化卫生制度,严格执行无菌操作规程,合理应用抗菌药物是控制医院感染发生的重要措施。 相似文献