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171.
目的:对近十年中国应用生理学杂志刊载的基金论文进行统计与分析,评价该杂志的学术地位和社会影响力。方法:运用文献计量学方法,对中国应用生理学杂志1999~2008年的载文、基金论文率、基金资助级别、作者所在区域等进行定量分析。结果:载文及基金论文数量不断增加;地方机构的基金数目在后五年所占比例明显提高;北京、浙江、天津地区为杂志重要来源。结论:中国应用生理学杂志已形成了自己独特的学术风格,具有较好的学术地位和社会影响力。 相似文献
172.
在生态学中,尺度问题一直是重点也是难点,多尺度胸径分布问题经常遇到且至今没有很好的解决方法,建立多尺度胸径分布统一模型是解决问题的关键;多尺度胸径分布统一模型的建立包括2方面的内容:第一,选择合适的概率分布函数,应用最大熵原理推出胸径分布统一模型,它具有明确的解析表达式,既能克服常用方法无法解释测树因子服从某种概率分布的真正原因,也能克服常用方法无法区分测树因子服从多种概率分布的不足,从而可以作为林分尺度测树因子概率分布的统一模型.第二,尺度与尺度转换,常用研究尺度问题的方法具有2个不足:(1)研究大尺度时损失了样地(林分尺度)资料的宝贵信息;(2)研究林分尺度时无法进行尺度转换.提出的联合最大熵概率密度函数可以克服常用研究尺度方法的以上2个不足,该函数的每一个组成部分都是最大熵函数;联合最大熵概率密度函数可以作为多尺度胸径分布统一模型,既可以最大限度的利用每个样地的信息,又可以进行多尺度的自由转换,从而为测树因子统计分布建模提供了一种有效方法;用森林资源连续清查样地中属于安吉的22个毛竹样地对文中提出的方法进行了验证,结果表明方法可行且对每个样地的拟合精度都很高. 相似文献
173.
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175.
Lindsay A. Crawford Daria Koscinski Kaitlin M. Watt Jeremy N. McNeil Nusha Keyghobadi 《Journal of Insect Conservation》2013,17(5):859-864
Non-lethal methods of tissue sampling are increasingly used for genetic studies of insect species and the effects of this approach have long been assumed to be minimal. Tissue removal has the potential to influence insect reproductive behaviours such as mate recognition, courtship or oviposition but the effects of non-lethal sampling on reproductive success have not been widely and adequately tested. Here, we test potential effects of both wing-clipping and leg removal on reproductive behaviours of the cabbage white butterfly (Pieris rapae). We conducted a total of 93 male and 59 female mating trials, and found no significant differences in mating success between treated (i.e., tissue removed) and control individuals in either sex. We also monitored the number and location of eggs laid by 58 females. We found no significant differences in egg-laying behaviour among leg removed and control individuals. Power analysis indicated that we had sufficient statistical power to detect moderate effects of treatment on both mating and oviposition. Our study provides the most comprehensive examination to date of the effects of non-lethal sampling on reproductive behaviours in a butterfly/insect species, and supports the contention that tissue sampling is non-detrimental. To fully comprehend the general impacts of tissue sampling on butterfly reproductive behaviour however, additional similar studies need to be conducted on a variety of species with differing mating behaviours. Only through meta-analysis, may it be possible to detect more subtle effects of tissue removal which cannot be revealed within a single study due to sample size limitations. 相似文献
176.
Vissers LE Stankiewicz P Yatsenko SA Crawford E Creswick H Proud VK de Vries BB Pfundt R Marcelis CL Zackowski J Bi W van Kessel AG Lupski JR Veltman JA 《Human genetics》2007,121(6):697-709
Recent molecular cytogenetic data have shown that the constitution of complex chromosome rearrangements (CCRs) may be more
complicated than previously thought. The complicated nature of these rearrangements challenges the accurate delineation of
the chromosomal breakpoints and mechanisms involved. Here, we report a molecular cytogenetic analysis of two patients with
congenital anomalies and unbalanced de novo CCRs involving chromosome 17p using high-resolution array-based comparative genomic
hybridization (array CGH) and fluorescent in situ hybridization (FISH). In the first patient, a 4-month-old boy with developmental
delay, hypotonia, growth retardation, coronal synostosis, mild hypertelorism, and bilateral club feet, we found a duplication
of the Charcot-Marie–Tooth disease type 1A and Smith-Magenis syndrome (SMS) chromosome regions, inverted insertion of the
Miller-Dieker lissencephaly syndrome region into the SMS region, and two microdeletions including a terminal deletion of 17p.
The latter, together with a duplication of 21q22.3-qter detected by array CGH, are likely the unbalanced product of a translocation
t(17;21)(p13.3;q22.3). In the second patient, an 8-year-old girl with mental retardation, short stature, microcephaly and
mild dysmorphic features, we identified four submicroscopic interspersed 17p duplications. All 17 breakpoints were examined
in detail by FISH analysis. We found that four of the breakpoints mapped within known low-copy repeats (LCRs), including LCR17pA,
middle SMS-REP/LCR17pB block, and LCR17pC. Our findings suggest that the LCR burden in proximal 17p may have stimulated the
formation of these CCRs and, thus, that genome architectural features such as LCRs may have been instrumental in the generation
of these CCRs. 相似文献
177.
Maximizing microbial degradation of perchlorate using a genetic algorithm: Media optimization 总被引:1,自引:0,他引:1
Kucharzyk KH Crawford RL Paszczynski AJ Soule T Hess TF 《Journal of biotechnology》2012,157(1):189-197
Microbial communities are under constant influence of physical and chemical components in ecosystems. Shifts in conditions such as pH, temperature or carbon source concentration can translate into shifts in overall ecosystem functioning. These conditions can be manipulated in a laboratory setup using evolutionary computation methods such as genetic algorithms (GAs). In work described here, a GA methodology was successfully applied to define sets of environmental conditions for microbial enrichments and pure cultures to achieve maximum rates of perchlorate degradation. Over the course of 11 generations of optimization using a GA, we saw a statistically significant 16.45 and 16.76-fold increases in average perchlorate degradation rates by Dechlorosoma sp. strain KJ and Dechloromonas sp. strain Miss R, respectively. For two bacterial consortia, Pl6 and Cw3, 5.79 and 5.75-fold increases in average perchlorate degradation were noted. Comparison of zero-order kinetic rate constants for environmental conditions in GA-determined first and last generations of all bacterial cultures additionally showed marked increases. 相似文献
178.
豚鼠主动脉前庭组织的自律性研究和形态学观察 总被引:33,自引:3,他引:33
用细胞内微电极技术,对82只豚鼠主动脉自发电活动进行观察和分析,表明,16例(19.5%)出现自律性电活动;61例(74.4%)在电刺激诱导下也可出现自律性电活动。进一步观察发现,在主动脉瓣右瓣与后瓣交界以下的局部区域,可记录到有明显4相自动增极化的慢反应自律细胞样的动作电位,并可被钙通道阻滞剂Mn^2+,硝苯吡啶阻断。这一部位之外的其它大部分区域均表现为快反应动作电位,经光镜和电镜观察(n=13 相似文献
179.
David C Currow Morag Farquhar Alicia M Ward Gregory B Crawford Amy P Abernethy 《BMC pulmonary medicine》2011,11(1):1-11
Background
End-stage lung disease (ESLD) is a frequent cause of death. What are the differences in the supports needed by caregivers of individuals with ESLD at end of life versus other life-limiting diagnoses?Methods
The South Australian Health Omnibus is an annual, random, face-to-face, cross-sectional survey. In 2002, 2003 and 2005-2007, respondents were asked a range of questions about end-of-life care; there were approximately 3000 survey participants annually (participation rate 77.9%). Responses were standardised for the whole population. The families and friends who cared for someone with ESLD were the focus of this analysis. In addition to describing caring, respondents reported additional support that would have been helpful.Results
Of 1504 deaths reported, 145 (9.6%) were due to ESLD. The ESLD cohort were older than those with other 'expected' causes of death (> 65 years of age; 92.6% versus 70.6%; p < 0.0001) and were less likely to access specialised palliative care services (38.4% versus 61.9%; p < 0.0001). For those with ESLD, the mean caring period was significantly longer at 25 months (standard deviation (SD) 24) than for 'other diagnoses' (15 months; SD 18; p < 0.0001). Domains where additional support would have been useful included physical care, information provision, and emotional and spiritual support.Conclusions
Caregiver needs were similar regardless of the underlying diagnosis although access to palliative care specialist services occurred less often for ESLD patients. This was despite significantly longer periods of time for which care was provided. 相似文献180.
崇明东滩盐沼植被扩散格局及其形成机制 总被引:8,自引:0,他引:8
长江河口盐沼植被的形成和演化是生物与其生长环境相互作用的结果。以崇明东滩盐沼植被典型扩散前沿为研究对象,2011至2012年期间调查了盐沼植被扩散前沿实生苗扩散、定居以及形成的扩散格局,同时测定了盐沼植被扩散前沿的潮滩冲淤动态和水文动力条件。研究结果表明,崇明东滩盐沼植被在扩散前沿形成了互花米草-光滩(Spartina alterniflora-Mudflat,SM)和互花米草-海三棱藨草-光滩(Spartina alterniflora-Scirpus mariqueter-Mudflat,SSM)两种典型的扩散格局。冲淤动态和水文动力条件是影响盐沼植被扩散格局的重要因子,尤其是在4—6月盐沼植物实生苗传播和定居的关键阶段。在此基础上,分析了东滩盐沼植被扩散前沿的生物-物理相互作用以及盐沼植被扩散格局的形成机制。研究结果不仅有助于理解长江河口地区盐沼植被扩散的生物物理过程,并对全球气候变化和海平面上升条件下滨海生态系统动态预测与湿地保护与管理具有重要的意义。 相似文献