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为确定高产脂云南松的早期选择指标,采用石蜡切片法对不同海拔、不同产脂量云南松的针叶、树干韧皮部和木质部的组成性树脂道特征进行解剖观察,结果表明：高产脂与低产脂云南松的针叶树脂道个数、树干木质部树脂道密度、韧皮部树脂道大小及单位长度树脂道数量存在极显著差异（P＜0.01）,但不同海拔之间无显著差异;高、低海拔高产脂云南松针叶树脂道数量分别比低产脂的高38.89％、30.34％,树干木质部树脂道密度分别高58.06％、48.48％,韧皮部树脂道大小分别高32.20％、29.73％,韧皮部单位长度树脂道数量分别高21.95％、38.51％.说明针叶树脂道数量、树干木质部树脂道密度及韧皮部树脂道大小3项指标,也可作为云南松产脂力评价的部分指标.

为探索毛竹从发笋到竹秆形成的组织发育规律,对不同发育时期和部位的毛竹茎秆进行组织解剖分析并进行数量化分析。结果表明：竹秆的快速发育主要表现在节间的纵轴方向,节间发育由细胞分裂和细胞伸长控制。发育初期,在薄壁细胞和纤维细胞上可以看到大量的细胞核出现,此时细胞分裂占主导地位;随着组织发育,细胞核逐渐减少并消失,薄壁细胞和纤维细胞的长度显著增加,细胞伸长在发育中后期占主导地位。竹秆的发育、成熟和老化从基部首先启动,中部和顶部要顺次晚一些。基部的纤维组织最先出现木质化,此时茎秆的高度大约为6 m。竹秆的细胞伸长呈阶段性的波动,薄壁组织的细胞长度在快速伸长期偏离正态分布,在缓慢伸长期呈正态分布。

以野生长蕊杜鹃半木质化茎段为试材,采用植物生长激素KIBA,KNAA和Hormodin对插穗进行处理,测定不同生根期内源激素IAA、GA3、ZR、ABA含量,对扦插不同时期插穗茎段进行电镜扫描。结果表明：先快蘸液态KNAA（3 000mg·L-1）,再迅速蘸取粉状Hormodin#1处理对插条生根具有显著影响,插穗生根率达到了81.25%;较高浓度的内源IAA含量有利于根原基分化形成,GA3含量上升与插穗愈伤组织的诱导、不定根的形成呈正相关性,低水平的ABA更有利于长蕊杜鹃扦插生根;插穗在根原基分化和愈伤组织形成时期消耗內源ZR,在不定根长出后自身合成ZR;通过对淀粉粒研究表明扦插期补充糖类物质是必要的,簇状晶体产生表明钙调控等生理机制形成。

研究了紫胶蚧觅食行为特点和紫胶蚧觅食时对寄主植物枝条的选择行为。结果表明：紫胶蚧觅食时有向前、向上寻找的特性，觅食初期前进路线的选择也采取ESS对策。紫胶蚧选择在1年生及其以下枝条上固定取食的比率达95％以上，1年生以上2年生以下枝条上固定取食的比率为5％，基本不在2年生及其以上枝条上固定取食。紫胶蚧分布与不同方向枝条之间无关。紫胶蚧取食久树枝条的枝径范围在0．47～1．60cm之间，枝径在0．6～1．1cm之间的占88%。在直立枝条上，紫胶蚧呈环状带分布，在多数倾斜枝条上，紫胶蚧分布在背阴面。比较解剖结果发现，久树2年生枝条背阴面的周皮、皮层明显比1年生枝条的增厚；石细胞和纤维细胞在皮层中分布数量多，连成带状，比久树1年生枝条中石细胞和纤维细胞组成的带状物要厚27μm；从周皮到韧皮部筛管的距离，久树2年生枝条的比1年生枝条要厚，枝条上端树皮的周皮、皮层比枝条基部树皮的要薄。枝条向阳面韧皮部厚度要比背阴面薄。

将“神舟”三号(SZ-3)飞船搭载的草地早熟禾品种纳苏干种子地面种植后，根据形态变化进行初步筛选，并通过分株扩繁出突变株系PM1、PM2和PM3。对这三个草地早熟禾突变株系的叶片解剖结构及过氧化物酶同工酶和酯酶同工酶进行观察。结果表明，与对照(CK)相比，三个变异株系由于细胞数目的增加使叶片宽度明显增加；叶肉细胞平均直径降低使叶片厚度减少；PM2、PM3株系叶片泡状细胞的增多，改变了叶片的形态。过氧化物酶同工酶谱带CK有11条，迁移率为4．63％～47．22％；PM1有21条谱带，迁移率为2．78％～68．52％；PM2有18条谱带，迁移率为2．78％～67．59％；PM3有20条谱带，迁移率为2．78％～63．89％。酯酶同工酶谱带CK有3条，迁移率为59．74％～94．81％；PM1有8条谱带，迁移率为38．96％～94．81％；．PM2有7条谱带，迁移率为48．05％～94．81％；PM3有8条谱带，迁移率为49．35％～94．81％。PM1、PM2和PM3三个株系与CK含有一部分完全相同的谱带，另一部分谱带发生了较大变化：分别出现了CK中没有的谱带和在CK中存在而三个变异株系没有的谱带。同时各谱带的强弱也发生了不同程度的变化。

对元谋干热河谷引种的8种外来树种进行了抗旱性分析，发现水分利用效率从高到低的顺序依次是：窿缘桉、赤桉、柠檬桉、绢毛相思、肯氏相思、厚荚相思、大叶相思、马占相思。水分利用效率越高，对干热环境的适应性越强。8种外来树种适应干热河谷生境的旱性结构的特点是主根深、侧根多、栅栏组织和贮水组织发达、构成等面叶或近等面叶。桉树类树种的蒸腾速率较高，但能生存的主要机理根系分布深，主动供水能力强，补充了地上部分的水分消耗；而相思类则以发达的根系和较高的叶片保水能力来适应干热环境。

The mucosal immune system defends against a vast array of pathogens, yet it exhibits limited responses to commensal microorganisms under healthy conditions. The oral-pharyngeal cavity, the gateway for both the gastrointestinal and respiratory tracts, is composed of complex anatomical structures and is constantly challenged by antigens from air and food. The mucosal immune system of the oral-pharyngeal cavity must prevent pathogen entry while maintaining immune homeostasis, which is achieved via a range of mechanisms that are similar or different to those utilized by the gastrointestinal immune system. In this review, we summarize the features of the mucosal immune system,focusing on T cell subsets and their functions. We also discuss our current understanding of the oral-pharyngeal mucosal immune system.

Background：Old pelvis fractures are among the most challenging fractures to treat because of their complex anatomy,difficult-to-access surgical sites,and the relatively low incidence of such cases.Proper evaluation and surgical planning are necessary to achieve the pelvic ring symmetry and stable fixation of the fracture.The goal of this study was to assess the use of three-dimensional （3D） printing techniques for surgical management of old pelvic fractures.Methods：First,16 dried human cadaveric pelvises were used to confirm the anatomical accuracy of the 3D models printed based on radiographic data.Next,nine clinical cases between January 2009 and April 2013 were used to evaluate the surgical reconstruction based on the 3D printed models.The pelvic injuries were all type C,and the average time from injury to reconstruction was 11 weeks （range：8-17 weeks）.The workflow consisted of.：（1） Printing patient-specific bone models based on preoperative computed tomography （CT） scans,（2） virtual fracture reduction using the printed 3D anatomic template,（3） virtual fracture fixation using Kirschner wires,and （4） preoperatively measuring the osteotomy and implant position relative to landmarks using the virtually defined deformation.These models aided communication between surgical team members during the procedure.This technique was validated by comparing the preoperative planning to the intraoperative procedure.Results：The accuracy of the 3D printed models was within specification.Production of a model from standard CT DICOM data took 7 hours （range：6-9 hours）.Preoperative planning using the 3D printed models was feasible in all cases.Good correlation was found between the preoperative planning and postoperative follow-up X-ray in all nine cases.The patients were followed for 3-29 months （median：5 months）.The fracture healing time was 9-17 weeks （mean：l0 weeks）.No delayed incision healing,wound infection,or nonunions occurred.The results were excellent in two cases,good in five,and poor in two based on the Majeed score.Conclusions：The 3D printing planning technique for pelvic surgery was successfully integrated into a clinical workflow to improve patient-specific preoperative planning by providing a visual and haptic model of the injury and allowing patient-specific adaptation of each osteosynthesis implant to the virtually reduced pelvis.

X-ray computed tomography （CT） has been widely used as a powerful diagnostic tool in clinics because it can provide high-resolution 3D tomography of the anatomic structure based on the distinctive X-ray absorptions between different tissues. Currently, CT contrast agents are mainly small iodinated molecules, which suffer from drawbacks such as short bloodretention time, nonspecific in vivo biodistribution, and renal toxicity. Utilization of nanoparticles as potential CT contrast agents to overcome the aforementioned issues has advanced rapidly. In this mini review, we introduce current research efforts in the development of nanoparticulate CT contrast agents and discuss the challenges for additional breakthroughs in this field.

Knowledge of the leaf anatomy of grassland plants is crucial for understanding how these plants adapt to the environment. Ti- betan alpine grasslands and Inner Mongolian temperate grasslands are two major grassland types in northern China. Tibetan alpine grasslands occur in high-altitude regions where the low temperatures limit plant growth. Inner Mongolian temperate grasslands are found in arid regions where moisture is the limiting factor. Few comparative studies concerning the leaf anato- my of grassland plants of the Tibetan Plateau and Inner Mongolian Plateau have been conducted. We examined leaf character- istics at 71 sites and among 65 species, across the alpine grasslands of the Tibetan Plateau and the temperate grasslands of the Inner Mongolian Plateau. We compared the leaf structures of plants with different life forms and taxonomies, and their adapta- tion to arid or cold environments. We explored relationships among leaf features and the effects of climatic factors （i.e., grow- ing season temperature and precipitation） on leaf characteristics. Our results showed that （i） there were significant differences in leaf anatomy between Tibetan alpine and Inner Mongolian temperate grasslands. Except for mesophyll cell density, the val- ues obtained for thickness of leaf tissue, surface area and volume of mesophyll cells were larger on the Tibetan Plateau than on the Inner Mongolian Plateau. （ii） Within the same family or genus, leaf anatomY showed significant differences between two regions, and trends were consistent with those of whole species. （iii） Leaf anatomy of woody and herbaceous plants also showed significant differences between the regions. Except for mesophyll cell density, the values obtained for the thickness of leaf tissue, and the surface area and volume of mesophyll cells were larger in herbaceous than in woody plants. （iv） Leaf ana- tomical traits changed accordingly. Total leaf thickness, thicknesses of lower and upper epidermal cells, and surface area and volume of mesophyll cells were positively correlated, while mesophyll cell density was negatively associated with those traits. （v） Growing season temperature had stronger effects on leaf anatomy than growing season precipitation. Although the communities in Tibetan and Inner Mongolian grasslands were similar in appearance, leaf anatomy differed; this was probably due to the combined effects of evolutionary adaptation of plants to environment and environmental stress induced by climatic factors.