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1.
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米科学、生物炼制、生物质能等也逐步成为微生物学研究的热门领域。为了更加系统、集中地反映各个领域  相似文献   

2.
《生物学杂志》2014,(5):I0001-I0001
1、《生物学杂志》是生命科学的综合性学术期刊,主要刊登动物、植物、微生物及生理、生化、遗传、生物技术、生物工程、分子生物学等生命科学领域的学术论文以及大中专院校生物教学等方面的经验介绍。主要栏目有:研究报告、综述与专论、技术方法、教学研究等。对反映国内外最新研究成果的论文、国家级自然科学基金资助的论文、获省、部级以上资助项目的科研成果论文将优先发表。  相似文献   

3.
第十一届国际化石刺丝胞与多孔类学术研讨会于2011年8月21—26日在比利时的列日大学召开。全球27个国家将近有100名代表出席会议。除了东道主比利时外,参加会议的有中国、俄罗斯、美国、英国、法国、加拿大、日本、澳大利亚、德国、意大利、荷兰、爱尔兰、西班牙、瑞士、奥地利、波兰、罗马尼亚、爱沙尼亚、  相似文献   

4.
《微生物学通报》2011,(11):1725
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米科学、生物炼制、生物质能等也逐步成为微生物学研究的热门领域。为了更加系统、集中地反映各个领域  相似文献   

5.
《微生物学通报》2011,(10):1601
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米科学、生物炼制、生物质能等也逐步成为微生物学研究的热门领域。为了更加系统、集中地反映各个领域  相似文献   

6.
桑粉虱形态研究   总被引:4,自引:0,他引:4  
研究描述了容易与杨梅粉虱混淆的重要害虫桑粉虱Pealius mori(Takahashi)成虫、卵、1~4龄若虫及蛹的形状、分类特征,包括成虫的体长、体色、触角、单眼、复眼、口器、翅、足及雌雄外生殖器;卵的形状、大小、卵色及卵柄;1~4龄若虫及蛹的形状、大小、体色、体周的刚毛、触角、口器、足、管状孔、盖瓣、舌状器及腹沟等。并比较桑粉虱与杨梅粉虱的主要分类特征。  相似文献   

7.
微生物生物技术(或称微生物技术)是一门以应用微生物学为主体的综合性技术群,主要包括微生物学、生物化学、遗传学及基因工程、细胞工程、酶工程、发酵工程和生化工程等。从纵向划分,包括研究、发展和生产。利用微生物技术生产的产品包括酒类、调味品、有机溶剂、有机酸、氨基酸、维生素、抗生素、甾体激素、酶制剂、活性肽及蛋白、酵母及其它单细胞蛋白、淀粉糖等。应用范围包括食品、轻工、医药、农业、化工、矿业和环境保护等方面。  相似文献   

8.
《植物杂志》2010,(10):30-31
1.黄瓜:黄瓜原产于印度,又叫青瓜、胡瓜、刺瓜等,其性平、味甘,具有明显的清热解毒、生津止渴等功效。黄瓜中富含蛋白质、糖类、维生素B2、维生素C、维生素E、胡萝卜素、尼克酸、钙、磷、铁等营养成分,同时还含有丙醇二酸、葫芦素、柔软的细纤维等成分,是难得的排毒养颜佳品。  相似文献   

9.
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米  相似文献   

10.
当前,随着生物技术的飞速发展,微生物学涵盖的领域越来越广,交叉学科的研究也越来越受到关注。除了已有的微生物学、病毒学、基因工程、细胞工程、酶工程、发酵工程之外,基因组学、代谢工程、纳米科学、生物炼制、生物质能等也逐步成为微生物学研究的热门领域。为了更加系统、集中地反映各个领域的研究成果,以及该领域学科的热点难点问题,充分发挥《微生物学通报》的学科引领和导向作用,促进学  相似文献   

11.
The genus Oreocharis as circumscribed here consists of 27 species including 5 varieties, of which 5 species and 4 varieties are described as new in the present paper. In the work analysed were the external morphology and geographic distribution and examined under SEM were pollen exine of 22 species and seed coat of 16 species. As a result, three types of the corolla, two types of the anther, three types of the pollen exine and three types of the seed coat are distinguished here in the paper. It is discovered that the corolla in the genus is relatively stable, though diverse, and highly correlated with the characters of pollen grains and seeds. The corolla clearly bilabiate but constricted at the throat, occurring in O. auricula, O. cordatula, O. aurantiaca, etc., for an example, is correlated with smooth, reticulate pollen exine and partial tectum and the reticulate and smooth seed coat. For this reason the subdivision of the genus in the paper is mainly based on the characters of the corolla, but combined with those of the anther, pollen and seed coat. The genus is divided into four sections in the present classification. Dasydesmus Craib, based on a single species. O. bodinieri, is reduced here, and the reasons are given. The genus is distributed mainly in the subtropics, and less frequently in the tropics, of China south of 32.5°N and east of 98.5°E, with only two species beyond the border, O. hirsuta in Thailand (only a single locality in Chiengmai) and O. aurea also found in north Vietnam (see Fig. 1, Table 3). Sect. 1. Stomactin (Clarke) Fritsch. Corolla urceolate-tubular, constricted at the throat, with limb distinctly bilabiate; anthers broad-oblong; seed coat reticulate, smooth, rarely minutely tuberculate; pollen exine fine-reticulate, tectum partial and smooth, luminae slightly unequal in size. Sect. 2. Orthanthera K. Y. Pan Corolla campanulate or campanulate-tubular; anthers broad-oblong; seed coat reticulate, muri smooth, rarely spiny-processed; pollen exine fine-reticulate, with partial and smooth tectum and luminae slightly unequal in size, rarely exine insular and fine-tuberculate, tectum perforate. Setc. 3. Oreocharis Corolla thin-tubular; anthers broad-oblong; seed coat densely spinyprocessed, rarely fine-tuberculate; pollen exine insular, densely spiny-processed, rarely finereticulate and smooth, luminae unequal in size. Sect. 4. Platyanthera K. Y. Pan Corolla campanulate; anthers hippocrepiform; seed coat densely spiny-processed; pollen exine fine-reticulate, tectum perforate, luminae small, nearly equal in size. In the section Stomactin, although the constriction of corolla at its throat is a specialized character, the characters of seed coat, pollen grains and anthers are apparently primitive. Therefore it may be said at least that more primitive characters are preserved in the section. In the section Oreocharis, on the contrary, the characters of corolla, seed coat and pollen exine are all advanced. And in the section Platyanthera, the seed coat, pollen (with perforate tectum) and anthers have developed rather specialized characters.  相似文献   

12.
林有润 《植物研究》2002,22(3):341-365
棕榈科原省藤亚科因其子房壁及外果皮被倒生、螺旋状排列的鳞片所覆盖,而区别于其他亚科,因而独立分出成一新科--省藤科。作者讨论了棕榈科的祖先种可能在石炭纪时,自原始裸子植物开以顿目在分化、衍生出苏铁目祖先种的进化干上,于白垩纪时分化出的一个分支。在棕榈科的祖先种出现不久后,在其进化的分支上,于白垩纪后期又分化出一旁支,成为棕榈科的姊妹科--省藤科的祖先种。从两祖先种分别再分化、衍生出现今分布地球上该二科的属与种。两科、尤其前者是被子植物、尤其是单子叶植物中最原始的类群之一。作者还提出棕榈科象牙椰亚科与贝叶棕亚科是该科最原始或较原始的两类群;槟榔亚科和腊材榈亚科是较进化的两类群;而水椰亚科祖先种可能源于象牙椰亚科的祖先种,但又演化为该科最进化与特化的类群。省藤科省藤亚科略比鳞果榈亚科原始。作者讨论了两科为泛热带分布的科,指出两科的"现代分布区"在南北两半球热带地区,少数种还延伸分布到两半球暖亚热带、甚至达中亚热带地区,分布区边缘最北达日本中部、中国长江流域及黄河下游的南部,美国加利佛尼亚州与佛罗里达州和地中海北部;最南达智利中部和新西兰南部;而"现代分布中心"在热带与暖亚热带的亚洲,中、南美洲,大洋洲及非洲的东、南、西部;但分布区的"密集中心"则在热带亚洲、热带中及南美洲、南太平洋群岛及非洲东南部。作者还介绍了近50年我国南方引种驯化成功的两科植物近400种(见*图谱),其中少数为耐寒的种类,有的种已引种到长江流域或更北的地区。引种的大部分种都有其重要的经济用途,包括:1. 食用,如淀粉和树液可制"西米"或制糖,酿酒、醋或作饮料;果或种子榨油,供食用或工业用;某些种的嫩芽作蔬菜,甚至种子代咖啡饮用;2. 药用,有消炎、止血、活血、驱虫、抗癌等用;3. 建筑、工艺与日用品,包括不少种的树干供建普通房子、桥梁、小船;少数种可提制工业用蜡;许多种的纤维制高级缆绳和编织品;还制工艺品与日用品等;4. 代表热带景观的园林工程、绿化及美化环境的观赏树和人行道树及建造园林景观生态类型的树种等。  相似文献   

13.
Antagonistic factors, broadly identified as antibiosis, competition and natural enemies, impact on entomopathogenic nematodes. Antibiosis can occur through the release of plant chemicals from the roots into the soil, which may adversely affect the host-finding behavior of the infective stage nematode, or the presence of these chemicals in the host insect may negatively affect nematode reproduction. In laboratory studies, intra-specific and inter-specific competition reduces nematode fitness, and inter-specific competition can cause local extinction of a nematode species. For example, after concomitant infection of a host, a steinernematid species usually excludes a heterorhabditid species. The mechanism for the steinernematid superiority has been postulated to be a bacteriocin(s) produced by Xenorhabdus, the symbiotic bacterium of the steinernematid, which prevents Photorhabdus, the symbiotic bacterium of the heterorhabditid, from multiplying. Inter-specific competition between two steinernematid species shows that both can co-exist in a host, but one species will eventually prevail in the environment. By having different foraging strategies, however, both steinermatid species may co-exist in the same habitat. An important issue is whether the introduction of an exotic entomopathogenic nematode species will competitively displace an indigenous nematode species. Although the environmental risks are small, the recommended policy is that the introduction of exotic nematodes be regulated. With other pathogens, entomopathogenic nematodes can out-compete entomopathogenic fungi, but not Bacillus thuringiensis, for the same host individual when both the nematode and entomopathogen are applied simultaneously. The best studied natural enemy is the nematophagous fungus, Hirsutella rhossiliensis, which causes higher mortality in Steinernema glaseri compared with Heterorhabditis bacteriorphora. Differential susceptibility to the fungus may be associated with the retention of the second-stage cuticle by H. bacteriophora. Invertebrate predators including mites and collembolans feed on entomopathogenic nematodes. Although a number of studies have been conducted with antagonists, there is a dearth of field data. We suggest that long-term research plots be established where natural populations of entomopathogenic nematodes occur and include antagonists as a component of such studies.  相似文献   

14.
竹类果实胚体的比较解剖与系统分类   总被引:5,自引:1,他引:4  
  相似文献   

15.
山东山旺Palaeomeryx化石的初步研究   总被引:2,自引:1,他引:1  
Palaeomeryx 在含义、性质和分类位置上,一直是一个争论较多的属.最近在山旺发现的 Palaeomeryx 完整骨架,为解决上述问题提供了有价值的资料和证据. Palaeomeryx 雄性具有一对眶上"皮骨角"和单一的"枕顶角".根据共近裔性状的分析,本文作者认为 Palaeomeryx 应该归入长颈鹿,作为这一支中最早分出的一个旁支.长颈鹿和鹿科有较近的亲缘关系,而和牛科的关系较远. Palaeomeryx 大概位于 Blastomeryx 和 Leptomeryx 之间,从反刍类主干中分出.山旺的材料,代表本属中一个较原始的新种: Palaeomeryx tricornis. 它的时代,可能相当于欧洲的 MN4 或 MN5.  相似文献   

16.
The Brachyura, within the decapod crustaceans, is one of the most species-rich taxa with up to 10 000 species. However, its phylogenetic history, evolution and fossil record remain subjects of controversy. In our study, we examined the phylogenetic relationships of the Brachyura based on morphological characters of the foregut. The cladistic analysis supports a monophyletic Brachyura including the Dromiidae and Raninidae. A clade comprising Dromiidae and Dynomenidae forms the most basal assemblage within the Brachyura, followed by the Homolidae and Latreilliidae. As a result, neither Podotremata nor Archaeobrachyura form a clade. In contrast, foregut data suggest that the classical taxon Oxystomata, comprising Calappidae, Parthenopidae, Dorippidae, Leucosiidae, Cymonomidae and Raninidae, is monophyletic. This makes the Heterotremata paraphyletic or polyphyletic. A newly established taxon, Neobrachyura, embraces some representatives of the Heterotremata and the monophyletic Thoracotremata.  相似文献   

17.
Epididymal fluid, which is derived from testicular fluid, contains several unusual compounds. Little information is available on the composition of the testicular fluid of primates, but the fluid of the ram, bull, boar, and rat contains high concentrations of inositol and certain amino acids. Analyses have been made of epididymal fluid collected from the cauda epididymis of the Rhesus monkey and several nonprimate species (e.g., ram, bull, dog, stallion, rabbit, guinea pig, rat, and hamster), but similar information on the human is lacking. Cauda epididymal fluid appears to be similar in composition from one mammalian species to another. However, the epididymal plasma differs considerably from blood, lymph, and other extracellular fluids. The environment of spermatozoa in the epididymis is, therefore, highly specialized, and presumably in some way contributes to the prolonged survival of spermatozoa in this organ, and provides substrates for the metabolism of the spermatozoa. The chief characteristics of the cauda epididymal plasma are the low concentration of inorganic ions and the high levels of several unusual organic constituents namely, glycerylphosphorylcholine, carnitine, sialic acid, amino acids, glycosidases, and phosphatases. At least one antifertility compound, namely, orally administered α-chlorohydrin, appears to be concentrated in the epididymis. Studies on laboratory animals, domestic species, and man, suggest that it inhibits enzymes of the glycyolytic pathway in spermatozoa, and this may be the basis for its antifertility activity.  相似文献   

18.
Cuttings of grapevine (Vitis vinifera L. cv. Chardonnay) were dark-forced at least three weeks. Pigment contents, 77 K fluorescence emission, excitation spectra of the leaves, petioles, stems, transmission electron micrographs of the etioplasts from leaves, the chlorenchyma tissues of the stems were analysed. The dark-grown leaves, stems contained 8 to 10, 3 to 5 μg/g fresh weight protochlorophyllide, its esters, respectively. HPLC analysis showed that the molar ratio of the unesterified, esterified pigments was 7:3 in the shoot developed in darkness. The dark-forced leaves contained carotenoids identified as: neoxanthin, violaxanthin, antheraxanthin, lutein, β-carotene. Detailed analyses of the fluorescence spectra proved that all tissues of the dark-forced shoots had protochlorophyllide or protochlorophyll forms with emission maxima at 628, 636, 644, 655, 669 nm. The 628, 636 nm emitting forms were present in all parts of the dark-forced shoot, but dominated in the stems, which may indicate an organ specificity of the etioplast development. Variations in the distribution of the pigment forms were even found in the different tissues of the stem. The subepidermal layers were more abundant in the 655 nm form than the parenchyma cells of the inner part of the cortex, the pith. In the latter cells, the plastid differentiation stopped in intermediary stages between proplastids, etioplasts. The plastids in the subepidermal layers had developed prolamellar body structures, which were similar to those of etiolated leaves. The results highlight the importance of organ-, tissue specificity of plastid differentiation for chlorophyll biosynthesis, greening of different plant organs. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

19.
Background and Aims A significant number of species assigned to the Neotropical orchid sub-tribe Oncidiinae reward insect pollinators with oil produced in floral glands termed elaiophores. The latter may be glabrous (epithelial elaiophores) or hirsute (trichomal elaiophores). Although the detailed anatomy and ultrastructure of epithelial elaiophores have been studied for a number of genera, such as Oncidium Sw., Gomesa R. Br. and Trichocentrum Poepp. & Endl., hitherto, trichomal elaiophores have been investigated only for a single species of Oncidiinae, Ornithocephalus ciliatus Lindl. Furthermore, this is the only representative of the Ornithocephalus clade to be investigated to date. Here, an examination is made of the elaiophore anatomy and ultrastructure of a further four species currently assigned to this clade (Ornithocephalus gladiatus Hook., Phymatidium falcifolium Lindl., Zygostates grandiflora (Lindl.) Mansf. and Zygostates lunata Lindl.) and the results compared with those obtained for other Oncidiinae. Methods Elaiophore structure was examined for all species at three stages of flower development: closed bud, first day of anthesis and final stage of anthesis, using light microscopy, fluorescence microscopy, scanning electron microscopy, transmission electron microscopy and histochemistry. Key Results Elaiophores of O. gladiatus occur upon the lateral lobes of the labellum and display characters intermediate between those of typical epithelial and trichomal elaiophores, in that they are largely glabrous, consisting mainly of cuboidal epidermal cells, but bear short, unicellular hairs proximally. By contrast, the elaiophores of all the other species investigated occur on the callus and are of the trichomal type. In P. falcifolium, these unicellular hairs are capitate. In all species, oil secretion commenced at the closed floral bud stage. Ultrastructurally, the mainly trichomal elaiophores of the four representatives of the Ornithocephalus clade closely resembled the epithelial elaiophores of other Oncidiinae, in that their cells displayed an organelle complement typical of lipid-secreting cells. However, in some taxa, a number of noteworthy characters were present. For example, the elaiophore cuticle of O. gladiatus and P. falcifolium was bi-layered, the outer layer being lamellate, the inner reticulate. The cuticle of Z. grandiflora and Z. lunata was also lamellate, but here, a reticulate layer was absent. Accumulation of secreted oil resulted in the localized distension of the cuticle. Cuticular cracks and pores, however, were absent from all species. The walls of the secretory cells of Z. grandiflora were also atypical in that they had short protuberances or ingrowths, and contained cavities which are thought to be involved in the secretory process. Conclusions Of the species investigated, most displayed similar anatomical organization, their trichomal elaiophores occurring on the labellar callus. They, thus, differ from many other members of the Oncidiinae, where epithelial elaiophores are found either on the callus, or on the lateral lobes of the labellum. However, ultrastructurally, all elaiophores, whether those of representatives of the Ornithocephalus clade, or those of other oil-secreting Oncidiinae, possessed a similar complement of organelles, regardless of whether the elaiophores were trichomal or epithelial. In view of the latter, and the similar chemical composition of oils derived from all Oncidiinae investigated to date, it is probable that position and type of elaiophore, and possibly the structure of the overlying cuticle, play an important role in pollinator selection in these oil-secreting orchids.  相似文献   

20.
This study surveys the external morphology of the mouthparts in the guild of spore‐feeders among the coleopterous superfamily Staphylinoidea, evaluating the influence of different phylogenetic and ecological starting points on the formation of their mouthparts. Our emphasis is on a scanning electron microscope analysis (SEM) of the involved trophic structures in spore‐feeding larvae and adults of the Ptiliidae, Leiodidae and Staphylinidae, describing the fine structure of their main functional elements. Functionally, mouthpart structures resemble brushes, brooms, combs, rakes, rasps, excavators, knives, thorns, cram‐brushes, bristle troughs, blocks and differently structured grinding surfaces. Their different involvement in the various aspects of the feeding process (i.e. food gathering, transporting, channelling and grinding) is deduced from our SEM analyses plus direct video observations. We infer five different patterns of food transport and processing, discriminating adults of ptiliids, leiodids plus staphylinids (excluding some aleocharines), several aleocharine staphylinids, and the larvae of leiodids and staphylinids. The structural diversity of the mouthparts increases in the order from (1) Ptiliidae, (2) Leiodidae towards (3) Staphylinidae, reflecting the increasing systematic and ecological diversity of these groups. Comparisons with non‐spore‐feeders show that among major lineages of staphylinoids, shifts from general microphagy to sporophagy are not necessarily constrained by, nor strongly reflected in, mouthpart morphology. Nevertheless, in several of these lineages the organs of food intake and grinding have experienced particular fine‐structural modifications, which have undergone convergent evolution, probably in response to specialized mycophagy such as spore‐feeding. These modifications involve advanced galeal rakes, galeal or lacinial ‘spore brushes’ with arrays of stout bristles, reinforced obliquely ventrad orientated prosthecal lobes and the differentiations of the molar grinding surfaces into stout teeth or tubercles. In addition, several staphylinids of the tachyporine and oxyteline groups with reduced mandibular molae have evolved secondary trituration surfaces, which in some aleocharines are paralleled by considerable re‐constructions of the labium–hypopharynx.  相似文献   

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