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131.
目的:考查郑氏熏洗药泡腾颗粒、软膏的镇痛效果,为其临床应用提供实验依据。方法:选取昆明小鼠160只,将每80只小鼠分为8组,空白对照组,阳性对照组,郑氏熏洗泡腾药颗粒高、中、低剂量组(分别简称为泡腾颗粒高、中、低剂量组),郑氏熏洗药软膏高、中、低剂量组(分别简称为软膏高、中、低剂量组),每组各10只。采用热板法和扭体法观察泡腾颗粒与软膏2种剂型对小鼠热刺激致痛反应及化学刺激致痛反应的影响,评价2种剂型的镇痛作用。结果:给药后,泡腾颗粒高剂量组30、60、120、240 min的痛阈值,中剂量组30、60、120 min的痛阈值均均增高,泡腾颗粒低剂量组30 min的痛阈值增高;软膏高、中剂量组30、60、120、240、360 min的痛阈值增高,软膏低剂量组30、60、120 min的痛阈值均增高,与空白对照组比较,差异均有统计学意义(P<0.05,P<0.01)。软膏高剂量组扭体反应的潜伏期较空白对照组升高(P<0.05);泡腾颗粒高剂量组,软膏高、中剂量组小鼠扭体次数较空白对照组减少,差异有统计学意义(P<0.05)。结论:郑氏熏洗药泡腾颗粒、软膏2种剂型均具有显著的镇痛作用,软膏较泡腾颗粒镇痛作用稍强。 相似文献
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133.
One new marine oligotrich ciliate, Omegastrombidium hongkongense n. sp., was isolated from a bloom of Noctiluca scuntillans near Port Shelter, Hong Kong. The morphology and infraciliature of this new species were studied on both living and protargol-stained specimens. Its phylogenetic position was discussed based on the sequence of the small subunit rRNA gene. O. hongkongense is different from its congeners with special characters. The cells are usually heart-shaped, and the cell size usually is (20–35) × (20–30) μm in vivo. Its deep buccal cavity extends obliquely to about 1/2 of cell length. It shows prominent apical protrusion. The adoral zone of membranelles is divided into 17–19 collar membranelles and four buccal membranelles. It has one ball-like macronucleus. The girdle kinety forms a closed loop which obliquely surrounds the body. The ventral kinety and thigmotactic membranelles are not observed. The SSU rRNA sequence of O. hongkongense was close to those of Strombidium paracalkinsi and Varistrombidium kelum with approximately 99% similarity. In the phylogenetic trees, O. hongkongense can be grouped with O. elegans and V. kielum species with very low support (16% ML). 相似文献
134.
In order to clarify the phylogeny and relationships of the most confused hypotrichous ciliates, Holosticha-complex, four closely related holostichids (five populations), Holosticha bradburyae, H. diademata, Anteholosticha sp., and A. manca, were compared and analyzed using ITS2 secondary structures, ITS1-5.8S-ITS2 region and SSrRNA gene sequences. The ITS1-5.8S-ITS2 region sequences of these four species were first sequenced, and they shared sequence identities ranging from 68.0% to 90.1%, while two populations of Anteholosticha sp. differed in three nucleotides (sequence identity 99.8%). There were several minor differences among ITS2 secondary structures of these species, while two populations of Anteholosticha sp. had the identical secondary structure. Phylogenetic trees inferred from the ITS1-5.8S-ITS2 region sequences of stichotrichs using multiple algorithms (Neighbor-Joining, Maximum Parsimony and Bayesian) revealed similar topologies. The results show that:(1) Holosticha bradburyae and H. diademata firmly clustered together with strong bootstrap supports, forming a sister clade with Anteholosticha sp., (2) Anteholosticha appeared to be a paraphyletic assemblage, in which the morphotype A. manca was more closely related to Diaxonella trimarginata than to its congener Anteholosticha sp. Phylogenetic analyses based on the SSrRNA gene and the combined sequences of SSrRNA gene and ITS1-5.8S-ITS2 region revealed the similar relationships between Holosticha and Anteholosticha, nevertheless their positions within the subclass Stichotrichia differed from each other inferred from different genes. 相似文献
135.
文章利用地面及探空气象观测资料、海洋站观测资料、ERA再分析资料,统计了日照市1988—2019年每年4—7月的海雾过程。分析了产生海雾的天气形势及形成机理,提出了影响日照地区海雾天气生成的主要气象要素及其配合效用。结果表明:春夏季节,日照地区处于入海变性高压西部、太平洋副热带高压脊西部或低压前部等几类天气形势控制下时,最易产生平流海雾过程;天气形势控制下的风向与风速、露点温度、气温、海温、层结稳定等水文气象要素在海雾形成过程起到重要作用。在此基础上,利用Fisher二级判别分析方法建立海雾预报的判别方程。通过预报检验发现,文章提供的海雾统计学预报方法具有良好的预报能力,预报准确率在88%~94%之间。可用来进行短期日照市海雾特征预报,为日照的工农业、渔业生产以及海上和陆地交通运输等提供服务。 相似文献
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137.
地震激发地球自由振荡过程的数值模拟初步探索 总被引:2,自引:0,他引:2
地球自由振荡的固有频率与地球内部结构密切相关,研究地球自由振荡可以深入研究地球内部结构。传统的解析方法侧重于本征频率的确定,但对从地震发生到地球自由振荡被激发的全过程难以研究。从弹性波动理论基础出发,试采用谱元法结合高性能并行计算数值模拟特大地震激发的弹性波在地球内部传播过程。在不考虑地球重力情况下,对数值模拟激发地球自由振荡的结果进行功率谱密度分析,通过对谱结果的观察并与理论值进行对比分析,认识到环型振型数值模拟结果可以准确重现其长周期理论频率值,地球重力对球型振型有重要影响。探讨了是否可以通过这种方法真实重现地球自由振荡激发的过程。以期利用此方法深入探讨地球横向不均匀性对地球自由振荡的影响。 相似文献
138.
Huai Zhang Yaolin Shi David A. Yuen Zhenzhen Yan Xiaoru Yuan Chaofan Zhang 《Pure and Applied Geophysics》2008,165(3-4):475-496
Modeling tsunami wave propagation is a very challenging numerical task, because it involves many facets: Such as the formation of various types of waves and the impingement of these waves on the coast. We will discuss the different levels of approximations made in numerical modeling of 2-D and 3-D tsunami waves and their relative difficulties. In this paper new attempts are proposed to evaluate the hazards of tsunami’s and visualization of large-scale numerical results generated from tsunami simulations. Specialized low-level computer language, based on a parallel computing environment, is also employed here for generating FORTRAN source code for finite elements. This code can then be run very efficiently in parallel on distributed computing systems. We will also discuss the need to study tsunami waves with modern software and visualization hardware. 相似文献
139.
Gene sequence-based genealogies of scuticociliates are different from those produced by morphological analyses. For this reason,
11 representative scuticociliates and two ambiguously related genera were chosen to test the ability of combined phylogenetic
analyses using both gene sequences and morphological/morphogenetic characteristics. Analyses of both the SSrRNA gene sequences
and the combined datasets revealed a consistent branching pattern. While the terminal branches and the order level relationships
were generally well resolved, the family level relationships remain unresolved. However, two other trees based on ITS1-5.8S-ITS2
region sequences and morphological/morphogenetic characters showed limited information, due to a lack of informative sites
in these two datasets. Our data suggest, however, that the combined analysis of morphological/morphogenetic characters and
gene sequences did produce some changes to the phylogenetic estimates of this group. 相似文献
140.
基于2001-2015年长江口系列的水下地形和水文测验等资料,研究了流域减沙对长江口典型河槽及邻近海域演变的影响。结果表明:三峡工程建成后的近10多年,流域年均输沙量处于1.35亿t左右的较低水平。受其影响,长江口口内的南支、南港和北港上段的含沙量2008年之后明显下降,河槽冲刷、容积扩大,河槽形态向相对窄深方向演化。而拦门沙河槽的上游侧和口外侧近年来亦有所冲刷,拦门沙浅滩长度缩短。长江口水下三角洲前沿位于北港口外和南北槽口外有两个冲刷区,2007年之后年平均冲刷厚度达0.1 m左右,年侵蚀沙量达0.71亿m3。流域减沙对长江口河槽演变的影响尚在进行中,可能改变长江口水下三角洲向海淤涨的历史演变模式。 相似文献