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11.
四种单宁植物形成层的活动周期和次生韧皮部的季节变化 总被引:3,自引:0,他引:3
余甘子Phyllanthusemblica.L杨梅Myricarubra(Lour).Sieb.etZucc,黑荆树AcaciamearsiiDeWilde形成层的活动有明显的季节性,形成层活动期分别为5~11月,3~12月,2~10月,其他时间休眠,细枝木麻黄CwasuarinacunninghaianaMiq的形成层周年都在活动1,2月的材料中也见到成膜林,4种树木在冬季都保留相当数量的具功能 相似文献
12.
本文报道了福建省3种假马齿苋属植物:麦花草、假马齿苋和匍匐假马齿苋,其中匍匐假马齿苋为我国新记录的归化植物,新近发表的田玄参是该种的同物异名,田玄参属相应地应归并入假马齿苋属。同时,还纠正了国内有关假马齿苋学名和文献引证中的错误。 相似文献
13.
Sun Yan Yuan Zhimin Guo Yuming Qin Yuanzhao Ban Yongtian Niu Hongxing Bu Yanzhen 《Annals of microbiology》2019,69(13):1407-1414
Previous studies have assessed the diversity of gastrointestinal bacteria in bats and reported that some of the strains are pathogenic to humans; therefore, bats are considered to be potential reservoirs of zoonotic pathogens. However, the bacterial diversity and types of pathogenic bacteria in the gastrointestinal tracts of Rhinolophus luctus and Murina leucogaster have not yet been determined. Humans frequently come into contact with these species; therefore, assessments of their gut microbiota, especially potential pathogens, are essential for public health. In the present study, MiSeq high-throughput sequencing was used to address this research gap, and the results were compared with those reported previously. The V3–V4 regions of the 16S rRNA gene were sequenced using the MiSeq high-throughput sequencing platform to determine the bacterial community of the stomach and the intestines of R. luctus and M. leucogaster. The bacteria in the gastrointestinal tracts of R. luctus and M. leucogaster were classified into three and four main bacterial phyla, respectively. In both R. luctus and M. leucogaster, the dominant phylum was Proteobacteria (stomach 86.07% and 95.79%, intestines 91.87% and 88.78%, respectively), followed by Firmicutes (stomach 13.84% and 4.19%, intestines 8.11% and 11.20%, respectively). In total, 18 and 20 bacterial genera occurred in a relative abundance of 0.01% or more in the gastrointestinal tracts of R. luctus and M. leucogaster, respectively. In R. luctus, the dominant genera were Lactococcus (10.11%) and Paeniclostridium (3.41%) in the stomach, and Undibacterium (28.56%) and Paeniclostridium (4.69%) in the intestines. In M. leucogaster, the dominant genera were Undibacterium (54.41%) and Burkholderia (5.28%) in the stomach, and Undibacterium (29.67%) and Enterococcus (7.19%) in the intestines. Among the detected gastrointestinal tract flora of R. luctus and M. leucogaster, 12 bacterial genera were pathogenic or opportunistic pathogens. A high number of human pathogens were detected in the gastrointestinal tracts of R. luctus and M. leucogaster, which demonstrates the urgency for increased efforts in the prevention and management of bat-to-human disease transmission from these species. 相似文献
14.
神农櫟(新种)(见图) 乔木,高10米,枝略粗壮,一年生枝具沟槽,紫棕色,无毛,二年生枝棕黑色,较老的枝具灰色的树皮,皮孔圆形,平坦,淡黄色,明显。芽鳞棕色,初被微柔及微纤毛,后渐脱落,最后无毛。叶近革质,二年后脱落,狭披针形,长6—8厘米,长为宽度的3—5倍,顶端渐尖,基部楔尖,沿叶柄下延,叶柄长2—3厘米,腹面平坦,基 相似文献
15.
在6个不同时间段对不同体色、世代和寄主条件下的麦长管蚜进行紫外胁迫,应用AFLP技术对麦长管蚜基因组变异进行分析.研究结果表明:处理时间与变异频率之间存在正相关(r=0.9466);不同体色型的蚜虫和不同抗性寄主饲养条件下的蚜虫对紫外胁迫表现出不同的抗性,红色型蚜虫的变异较强,高抗寄主上的蚜虫变异较弱;F1代可累代遗传. 相似文献
16.
本研究旨在开发基于微生物燃料电池(microbial fuel cell,MFC)的微生物电化学传感器对水环境重金属污染进行实时在线监测。构建微生物电化学传感器,采用错流式布水方式、优化外阻值及外循环速率等参数,在最优参数下分析重金属模拟废水浓度对电压的抑制情况。结果表明,当外阻值为130Ω、外循环速率为1.0 mL/min时,MFC电化学传感器的性能最优。在此条件下对1–10 mg/L的Cu2+、0.25–1.25 mg/L的Cd2+、0.25–1.25 mg/L的Cr6+和0.25–1.00 mg/L的Hg2+均有响应,60 min内输出电压最大抑制率分别可达92.95%、73.11%、82.76%和75.80%,线性相关系数均大于0.95,且有较好的生物学重复性。该MFC电化学传感器具有良好的重金属检测性能,可为实现水环境重金属污染实时在线监测技术的实际应用提供理论依据。 相似文献
17.
Jian Yang Xinxin Liu Danni Ai Jingfan Fan Youjing Zheng Fang Li Li Huo Yongtian Wang 《PloS one》2015,10(6)
Objectives
Fever of unknown origin (FUO) remains a challenge in clinical practice. Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is helpful in diagnosing the etiology of FUO. This paper aims to develop a completely automatic classification method based on PET/CT data for the computer-assisted diagnosis of FUO.Methods
We retrospectively analyzed the FDG PET/CT scan of 175 FUO patients, 79 males and 96 females. The final diagnosis of all FUO patients was achieved through pathology or clinical evaluation, including 108 normal patients and 67 FUO patients. CT anatomic information was used to acquire bone functional information from PET images. The skeletal system of FUO patients was classified by analyzing the standardized uptake value (SUV) and the PET index of bone glucose metabolism (PIBGM). The SUV distributions in the bone marrow and the bone cortex were also studied in detail.Results
The SUV and PIBGM of the bone marrow only slightly differed between the FUO patients and normal people, whereas the SUV of whole bone structures and the PIBGM of the bone cortex significantly differed between the normal people and FUO patients. The method detected 43 patients from 67 FUO patients, with sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 64.18%, 95%, 93.48%, 72.73%, and 83.33%, respectively.Conclusion
The experimental results demonstrate that the study can achieve automatic classification of FUO patients by the proposed novel biomarker of PIBGM, which has the potential to be utilized in clinical practice. 相似文献18.
Zhihui Ma Yongtian Qin Yafei Wang Xiaofeng Zhao Fangfang Zhang Jihua Tang Zhiyuan Fu 《PloS one》2015,10(12)
A long period of silk viability is critical for a good seed setting rate in maize (Zea mays L.), especially for inbred lines and hybrids with a long interval between anthesis and silking. To explore the molecular mechanism of silk viability and its heterosis, three inbred lines with different silk viability characteristics (Xun928, Lx9801, and Zong3) and their two hybrids (Xun928×Zong3 and Lx9801×Zong3) were analyzed at different developmental stages by a proteomic method. The differentially accumulated proteins were identified by mass spectrometry and classified into metabolism, protein biosynthesis and folding, signal transduction and hormone homeostasis, stress and defense responses, and cellular processes. Proteins involved in nutrient (methionine) and energy (ATP) supply, which support the pollen tube growth in the silk, were important for silk viability and its heterosis. The additive and dominant effects at a single locus, as well as complex epistatic interactions at two or more loci in metabolic pathways, were the primary contributors for mid-parent heterosis of silk viability. Additionally, the proteins involved in the metabolism of anthocyanins, which indirectly negatively regulate local hormone accumulation, were also important for the mid-parent heterosis of silk viability. These results also might imply the developmental dependence of heterosis, because many of the differentially accumulated proteins made distinct contributions to the heterosis of silk viability at specific developmental stages. 相似文献
19.
This study proposes a novel adaptive mesh expansion model (AMEM) for liver segmentation from computed tomography images. The virtual deformable simplex model (DSM) is introduced to represent the mesh, in which the motion of each vertex can be easily manipulated. The balloon, edge, and gradient forces are combined with the binary image to construct the external force of the deformable model, which can rapidly drive the DSM to approach the target liver boundaries. Moreover, tangential and normal forces are combined with the gradient image to control the internal force, such that the DSM degree of smoothness can be precisely controlled. The triangular facet of the DSM is adaptively decomposed into smaller triangular components, which can significantly improve the segmentation accuracy of the irregularly sharp corners of the liver. The proposed method is evaluated on the basis of different criteria applied to 10 clinical data sets. Experiments demonstrate that the proposed AMEM algorithm is effective and robust and thus outperforms six other up-to-date algorithms. Moreover, AMEM can achieve a mean overlap error of 6.8% and a mean volume difference of 2.7%, whereas the average symmetric surface distance and the root mean square symmetric surface distance can reach 1.3 mm and 2.7 mm, respectively. 相似文献
20.
Liu Weiguang Hu Bin Du Zhiyuan Wang Zi Zhou Xinzhu Liu Juan Wang Yongtian 《Plasmonics (Norwell, Mass.)》2018,13(1):275-280
Plasmonics - Graphene shows extraordinary optical and electrical properties that can be combined with some metallic micro-nanostructures. We experimentally investigated the electric tuning of Raman... 相似文献