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新疆木灵藓科植物的初步研究   总被引:3,自引:0,他引:3  
在研究标本和文献的基础上,报道了新疆产木灵藓科植物3属14种,即:瓶藓属Amphiduim(1种),木棂藓属Orthotrichum(12种)和木衣藓属Drummondia,对它们的生境、识别特征和地理分布作了初步讨论,并编制了新疆木灵藓科植物的分属、分种检索表。  相似文献   

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目的探索一种从人中鼻甲分离培养嗅鞘细胞的方法并鉴定所获得的细胞。 方法通过手术获取人中鼻甲黏膜组织,随后进行两步消化并剥离黏膜上皮组织,得到体积较小的组织块,再进行组织块原代(传代)培养并加压筛选,最终得到双极或多极样细胞并对获得的细胞进行免疫荧光鉴定。上皮样细胞比例、S100β和p75阳性细胞比例用 ±s表示,组间比较采用独立样本t检验。 结果将不剥离上皮层与剥离上皮层培养的原代细胞中上皮样细胞的比例进行对比,发现上皮层组上皮样细胞比例为(92.23±3.93)%高于剥离上皮层组上皮样细胞的比例(77.63±2.97)%,差异具有统计学意义(t = 5.129,P = 0.007)。采用剥离上皮层法培养原代细胞,经过加压筛选的细胞呈现双极或多极样,符合嗅鞘细胞形态学特点。免疫荧光染色发现,S100β阳性细胞占总细胞量的(8.1±1.7)%,而p75阳性细胞占总细胞量的5%以下,达到国内外研究同等水平。 结论通过使用两步消化法和加压筛选联合的方法从人中鼻甲粘膜组织中成功获得了人中鼻甲嗅鞘细胞,相比较传统方法,细胞分离培养周期明显缩短。  相似文献   

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采用向硫化矿培养基中补加FeSO4的方式以维持Fe2+ 浓度为4~8 g/L,可使嗜酸氧化亚铁硫杆菌菌浓在培养39 h时达到6.25×108 cells/mL,并在比生长速率几乎不降低的前提下提高了转化率和生产强度.然后对低氧化还原电位下低品位黄铜矿的浸出进行初步研究,结果表明经过30 d浸出,铜的浸出率可达28.5%...  相似文献   

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Summary Lucifer Yellow-Dextran labelling of lower layer cells (LLC), sometimes together with upper layer cells (ULC), of the 64-cellBarbus conchonius embryo resulted in labelled primordial germ cells (PGCs) at 12 h after fertilization (a.f.) in about 25% of cases. The presence of labelled PGCs was independent of the location of the injected blastomere with respect to the later orientation of the embryonic axis. After injection of an ULC alone, however, labelled PGCs were never found. Also, the distribution of labelled somatic cells differed between the ULC- and LLC-injected embryos. When we found fluorescent PGCs, only a few of them were labelled, suggesting that either a single predecessor exists earlier than the 64-cell stage or that the formation of germ cells is a polyclonal process. Tracing the fluorescent cells at successive stages of development shows an extensive mixing with unlabelled cells during the epiboly stage, which might well be the cause of partly unpredictable cell lineages. The chance of being committed to a specific fate is different for the ULC and LLC descendants. This might be due to relatively limited cell mixing between these two cell populations.  相似文献   

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The recent development of intensive rearing of European perch Perca fluviatilis in warm water effluents revealed important pathological problems. This study gives a preliminary overview of parasites and diseases encountered in experimental perch farming. No virus has been recorded since the beginning of the experiments in 1993. By contrast, mass mortality caused by bacterial disease alone or associated with other pathogens were frequently observed. The main identified bacterial species were: Aeromonas sp., A. veronii, A. hydrophila, Streptococcus sp., Staphylococcus sp., Vibrio fluviatilis and Enterobacter agglomerans. Protozoans were the most common parasites observed on cultured P. fluviatilis. High mortality rate due to Ichthyobodo necator and Trichodina sp. may take place at different stages of perch rearing. In contrast, the infestation by Ambiphrya sp. and Heteropolaria sp. was size- or age-related; these two ciliates infested perch weighing < 1 g and > 20 g, respectively. In spite of the presence of other parasites such as Ichthyophthirius multifiliis, Hexamita spp., Gyrodactylus sp. and Argulus sp. in the rearing system P. fluviatilis does not appear to be affected. Further abnormalities or diseases inherent to intensive culture systems are also described.  相似文献   

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安徽省外来杂草的初步研究   总被引:10,自引:0,他引:10  
经过大量调查和对文献资料的整理分析,结果表明安徽省约有外来杂萆55种,隶属44属,23科,还探讨了安徽外来杂草的特征、入侵途径及适应机制,并提出了对外来杂草的防治对策。  相似文献   

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老龙洞史前遗址初步研究   总被引:1,自引:1,他引:0  
白子麒 《人类学学报》1998,17(3):212-229
本文记述了老龙洞史前遗址研究初步成果.在对石、骨、角制品的一般性质论述基础上,指出这一组合具有自身的一些特点,并有着文化上的广泛联系;依遗物和哺乳动物化石对其年代也作了初步讨论。初步研究结果表明,它是中国西南地区,特别是云南近年来发现的一处重要的包括旧石器时代晚期文化层在内的史前洞穴遗址,为研究中国南方旧石器时代晚期文化类型的多样性提供了一个重要的地点和一批有意义的文化遗物。  相似文献   

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重庆地区蕨类植物区系的初步研究   总被引:7,自引:0,他引:7  
对重庆地区蕨类植物从科、属分布区类型进行了统计分析,同时将该区区系特征与其它几个地区进行了对比分析。结果表明:(1)该区共有蕨类植物389种(含变种和变型),隶属于109属, 43科。(2)该区蕨类植物中优势科、属十分明显,其中优势科为:鳞毛蕨科、金星蕨科、水龙骨科、蹄盖蕨科、凤尾蕨科;优势属为鳞毛蕨属、耳蕨属、凤尾蕨属、铁角蕨属、卷柏属、凤丫蕨属。(3)从蕨类植物科、属分布区类型的所占比例来看,该地区区系性质以热带成分占优势,其中热带分布科22科,占总科数的75.00%;热带分布属有60属,占总属数的64.52%(剔除世界分布)。(4)本区区系成分古老,古老孑遗的科属较为丰富,但特有现象不明显。(5)该区地形、气候条件对于蕨类植物的散布和充分发育比较适宜,为其在该区的充分发育创造了极为有力的条件。(6)经对比分析和聚类分析表明:该区与临近的几个地区属的相似性系数很高,特别是与西南地区的西藏、横断山区的属相似性系数较大,表明区系上与这些地区有着广泛的联系;而与华北的内蒙古,东北的辽宁等相距较远的地区属的相似性系数较低,表明区系上联系较为疏远。  相似文献   

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丹霞山风景地貌的植物区系研究   总被引:11,自引:0,他引:11  
刘蔚秋  李植华  刘兰芳   《广西植物》1999,19(1):15-21
描述了丹霞山植物区系的特征,对其科、属、种进行系统分析,并与邻近地区植物区系作了对比研究,探讨了丹霞地貌对本区植物区系组成成分的影响。丹霞山植物区系体现了华夏植物区系的特征,其表征科有不少同时也是华夏区系的表征科。从属的地理分布区类型来看,以泛热带分布局的比例最高,其次为热带亚洲分布属、东亚分布局及北温带分布属。丹霞山植物区系相对其纬度来说热带性较强,这与其特定的地貌特征有关。另外,本区的苦藓植物较为丰富,据初步统计共有27科70属,其中石生性苔藓分布尤其广泛。  相似文献   

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The present paper is a result of taxonomic study of Chinese Styracaceae plants. It contains 9 genera, 48 species, of which 2 species, 2 varieties are described as new and 2 new combinations are made, 21 species or varieties previously known to botanists distinctly are here reduced to synonyms. Besides the author also discuss about itsgeographical distribution in China and the main systematic characteristics of Styrax.  相似文献   

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水稻抗草品种选育研究初报   总被引:4,自引:0,他引:4  
利用PI312777抗草稻种材料,与本单位优质稻核心种质及其衍生系统材料广泛杂交配组,创建一批以PI312777衍生系统为主的新型育种材料。建立水稻抗草育种圃,重点针对抗草特性和综合农艺性状,通过田间抑草效应筛选,培育水稻抗草苗头株系,在稳定世代(F4代以上)应用以水稻特征次生物质为标记评价水稻品种(系)化感潜力的方法,辅助选育水稻抗草新品种(系)。初步提出适合华南稻区的以田间筛选和评价为主,以特征次生物质标记评价水稻品种(系)化感潜力的方法为辅,田间与实验室相结合,操作性强、简便有效的水稻抗草育种方法。  相似文献   

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王健生  赵洪斌 《昆虫知识》1998,35(4):221-223
黑尾卷象ApoderusnigroapicatusJekel近年来在山东荣成地区是危害刺槐的主要害虫。1年发生2代,以成虫于土中越冬。5~9月危害,10月上旬入土越冬。卵、幼虫、蛹在卷叶筒内生活;成虫食叶危害。本文报告了该虫的形态特征、年生活史、生活习性及天敌等,并提出了防治措施。  相似文献   

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This paper is a preliminary study on the Sabiaceae in aspects of its morphology, taxonomy and geography. We propose that the Sabioideae and Meliosmoideae as two new subfamilies of Sabiaceae according to the external morphology, flower structure and geographical distribution of these two genera respectively. This paper follows the taxonomic concepts of Luetha Chen on Sabia and C. F. van Beusekom on Meliosma. We agree with them for their classification of these two genera above the specific rank. As to the revision work of Sabia by van de Water and C. F. van Beusekom’s work on Meliosma we disagree for their unduly broad specific concepts. We rather treat the species of these two genera according to their habitats in regions on a relatively narrower sense. The genus Sabia of China are classified into 2 tribes, with 16 species, 5 subspecies and 2 varieties in which 4 subspecies and l variety are as new combinations, the genus of Meliosma in China are classified into 2 subgenera with 29 species, and 7 varieties of which 4 varieties are new combinations. After examining the affinity of the species of Sabia and Meliosma in China and its neighboring nations such as Burma, Japan and Bhutan, we found that their migration initiated from China, as the primitive species of these two genera occured in northeast and central part of Yunnan, sou theast of Sichuan, north of Guizhou and west of Hubei, the region may probably be the main origin of these two genera. As shown in tables 1 & 2, the localities where the species of these two genera densely populate they are from Yunnan, Guangxi, and Guangdong coinciding with the concepts of C. F. van Beusekom and van de Water about the distribution of exotic species of these two genera, it may reasonable be pointed out that the center of distribution of these two genera is Yunnan, Guangxi, Guangdong and nieghboring nations, upper Burma and northern Vietnam. Futhermore, it may be seen that starting from this center the number of species become less and less as they proceed far and far awaybut become more advance in evolution.  相似文献   

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利用大豆粉、玉米粉、麦胚和鲜茭白等成分配制了大螟Sesamia inferens(Walker)的半合成人工饲料,利用该饲料配方,发展了大螟的长期、继代饲养技术,即初孵-2日龄幼虫在茭白上饲养,3日龄-化蛹在人工饲料上饲养。利用该方法连续饲养大螟3代,幼虫的发育历期、蛹重、幼虫存活率、化蛹率、羽化率、卵孵化率和单雌产卵量等生活史参数与在天然饲料茭白上饲养的大螟相比,二者没有任何显著差异。而且利用该方法饲养,成本低、省工省力,能显著减少病原菌的感染。这说明该饲养技术适于大螟种群的长期、继代饲养。  相似文献   

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正貂熊(Gulo gulo)属食肉目,鼬科,貂熊属。此种有两个亚种,分别为古北亚种(G.g.gulo)和新北亚种(G.g.luscus)。新北亚种分布在北美北部地区;古北亚种分布在欧亚大陆,我国分布为此亚种(朴仁珠和张明海,2000)。貂熊主要栖息在高山、苔原、泰加林、北方森林区域、沼泽等环境(Mitchell-Jones et al.,1999)。目前,欧洲种群  相似文献   

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