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1.
Morphogenetic evolution of hydroid colony pattern   总被引:1,自引:1,他引:0  
Marfenin  N. N.  Kosevich  I. A. 《Hydrobiologia》2004,530(1-3):319-327
A scheme of evolution of hydrozoan colony pattern is proposed based upon the consideration of macro-morphogenesis. Four main processes play decisive roles(1) hard skeleton formation by soft tissues, (2) changes in duration of the growth phase relative to the transition to differentiation in interdependent zones of growth, (3) ratio in growth rates between adjacent zones of growth within the rudiment, the shoot, or the whole colony, and (4) spatial relationships among growth zones. The main tendency in morphological evolution of the hydroids is an increasing integration of the colony as revealed by increasing complexity of its structure. That is from a temporary colony towards the permanent one with highly organised shoots, as hydranths and branches are localised in a strictly arranged manner. An analysis of diverse data allows one to state that the main morphogenetic mechanism of increasing complexity in the hydroid colony is convergence, then fusion, of adjacent growth zones, a variant of heterochrony.  相似文献   

2.
3.
Shu Matsuura 《Mycoscience》1998,39(4):379-390
To clarity the effects of nutrient concentration and diffusion on the pattern formation of fungal colonies, the colony patterning ofAspergillus oryzae at various nutrient and agar levels was studied experimentally and was summarized in a colony morphology diagram. Roles of the nutrient content and the relaxation of nutrient distribution on the colony patterning were discussed based on a computer model of the mycelial growth. The colony morphology changed from compact to ramified as the nutrient and agar levels were lowered. No clear boundary was found between these two morphologies. The deterioration of substrate around the growing colony was detected when the morphic switching from homogeneous into splitting patterns emerged in the growth of ramified colonies. In the mycelial growth model, dense compact colonies developed at low growth rates and high nutrient influx into the colonized area. Under low nutrient levels, splitting colonies appeared at high growth rates as compared with the nutrient influx.  相似文献   

4.
采用马尾松(Pinusmassonianalamb)、东北松(PinusSpp.)、北美黄杉(花旗松)(Pseudotsugamenziesii)、青岗(CyclobalanopsisSpp.)、荷木(SchimaSpp.)作为截头堆砂白蚁Cryptotermesdomesticus(Haviland)的食料,研究其原始繁殖蚁配对后新建群体的形成和发展,从饲养的新建群体中培养产生了下一代的原始繁殖蚁,完成了1个世代的生活周期观察。试验证实,截头堆砂白蚁在广州市室温下,产生下一代原始繁殖蚁(完成1个生活周期)为7年;在湛江市室温下6、7年;而在恒温27℃,相对湿度80%的条件下只需2~3年。  相似文献   

5.
研究了水杨酸、萘乙酸及青霉素对大白桩菇、褐环粘盖牛肝菌及野蘑菇菌丝生长的影响。结果表明:对大白桩菇,水杨酸的致死浓度不大于1.94×10-4g/mL,培养基中浓度大于1.07×10-4g/mL抑制大白桩菇菌丝生长,浓度在(5.6×10-7)~(5.6×10-5)g/mL范围内能够促进菌丝生长,浓度小于5.6×10-8g/mL则没有明显影响。对褐环粘盖牛肝菌,培养基中水杨酸浓度大于4.76×10-6g/mL有抑制菌丝生长的作用,致死浓度不大于1.90×10-4g/mL。培养基中水杨酸浓度在大于5.6×10-6g/mL条件下对野蘑菇菌丝生长有一定的抑制作用。培养基中萘乙酸浓度在0.056 6~2.264 mg/L范围内对大白桩菇菌丝生长有一定的促进作用。培养基中萘乙酸浓度在0.95~4.75、0.056 6~1.132 mg/L范围内分别对褐环粘盖牛肝菌、野蘑菇菌丝生长基本无影响。培养基中青霉素浓度在(4.57×10-7)~(4.57×10-3)g/mL范围内对褐环粘盖牛肝菌菌丝生长具有抑制作用。培养基中青霉素浓度较低时对大白桩菇菌丝生长起促进作用,浓度大于1.88×10-3g/mL时对大白桩菇菌丝生长起抑制作用。而培养基中青霉素浓度在(1.88×10-7)~(1.88×10-3)g/mL范围内对野蘑菇菌丝生长无明显作用。  相似文献   

6.
对家白蚁Coptotermes formosanus Shiraki雌雄繁殖蚁在初建群体形成过程中氨基酸含量变化的测定,初步认为与产卵、哺育幼蚁和交尾有密切关系。产卵高峰期、哺育幼蚁期和交尾期氨基酸含量骤然下降,而产卵间歇期又开始回升。同时发现,雌雄蚁体重的变化对氨基酸含量的变化没有明显影响。  相似文献   

7.
The proliferation and maturation of granulocytic-monocytic stem cells appears to be controlled by a series of closely related glycoproteins termed “colony-stimulating factors” (CSFs). Recently, we devised a 6-step scheme for the purification of murine fibroblast (L-cell)-derived CSF. Ten liter pools of conditioned media were concentrated by ultrafiltration, precipitated by ethanol, and separated on DEAE cellulose, Con-A Sepharose, and Sephadex G 150. The CSF was separated from trace contaminants, including endotoxin, by density gradient centrifugation. The purified material was radioiodinated and used to define the serum half-life and in vivo distribution. Following IV injection there was a biphasic serum clearance with a t½ of 24–40 min and 2–2½ hours in the first and second phases. Approximately 25% of the tracer was excreted in the urine at 6 h; however, urinary radioactivity was due to low molecular weight peptides. Simultaneous studies by radioimmunoassay showed a similar rapid serum clearance of unlabeled CSF but virtually no urinary CSF activity. Thus, assays for urinary CSF may not provide useful measures of in vivo CSF activity. Further in vitro studies have defined the interaction of CSF with responsive cells in the marrow. Varying doses of CSF were incubated with 107 marrow cells for intervals of 24–48 h. The major increment in cell-associated radioactivity occurred between 6 and 16 h. The reaction was saturable with 1–2 ng/ml CSF. Binding was prevented by cold CSF, but not by other proteins. Irradiation yielded only a minimal reduction in CSF binding. The interaction of CSF with marrow cells appeared to require new protein synthesis, as binding was completely inhibited by cycloheximide and puromycin. Irradiated mice injected with antibodies to CSF showed an inhibition of granulopoiesis by marrow cells in peritoneal diffusion chambers; however, granulopoiesis in the intact bone marrow was unaffected. Granulpoiesis in long-term marrow cultures was also unaffected by anti-CSF. These different responses may be due to accelerated clearance of injected CSF in nonirradiated mice or to extensive stromal interactions that modulate and perhaps control granulocytic differentiation in the intact bone marrow microenvironment.  相似文献   

8.
人骨髓细胞体外培养液中含有高活力的 CSF,在长期培养过程中,CSF 活力的变化,与 CFU-C 数量的变化有大致平行的趋势。这种 CSF 对狗和小鼠也同样有效。人骨體条件液中的 CSF 对培养中的 CFU-S 也有明显的激发作用。这一结论可以从几个方面获得证据:第一,小鼠骨髓细胞与人骨髓条件液保温六小时后,再测定其中 CFU-S 数,结果是增加了。第二,经亚致死剂量照射的小鼠,腹腔注射适量的人骨髓条件液,其内源性脾结节也明显增多。第三,采用阿糖胞苷自杀的方法,测定小鼠骨髓经与人骨髓条件液保温后,其中 CFU-S 的自杀率也有增高的趋势。上述几方面的实验,说明人骨髓长期培养中存在着某种活性物质,调节体外造血。至于这种物质的来源,以及在体外造血中所起的作用,还需要做很多工作,逐步予以澄清。  相似文献   

9.
通过室内外饲养 ,观察了我国红光熊蜂蜂群的建立和发展动态。结果表明 ,在温度 2 8± 0 .5℃ ,相对湿度 70± 5 %和无光照的环境条件下 ,平均 84 .85 %越冬红光熊蜂蜂王在饲养后 11.83± 6 .13天开始产卵 ;加入欧洲熊蜂的幼工蜂能够刺激蜂王产卵 ,促使产卵期明显提前 ;健康且已受精的越冬蜂王一般在 2周内产卵 ;在开始饲养后 1个月左右开始出现工蜂 ,2月左右开始产生雄峰 ,雄峰出现后 7d左右产生蜂王。在采集并饲养的蜂王中 ,平均 78.79%的蜂王建立了蜂群 ,每群平均有蜂 180 .2 9± 80 .2 6头 ,其中工蜂 10 5 .90± 4 1.83头 ,雄蜂 6 5 .5 2± 4 5 .33头 ,蜂王 8.86± 12 .38头  相似文献   

10.
Summary Two continuous cell lines derived from long-term cultures of AKR mouse bone marrow adherent cells were isolated. These cell lines release colony stimulating activity (CSA), a factor that induces in vitro differentiation of granulocyte-macrophage progenitor cells. The colony forming cells and cluster forming cells in mouse marrow responsive to CSA from cell line conditioned medium were compared with those responsive to CSA from mouse lung conditioned medium (MLCM). Colony forming cells were characterized by analysis of their density distribution after equilibrium centrifugation in density gradient. Cluster forming cells were characterized by analyzing the progeny of individual clusters after transfer to fresh semisolid culture medium containing MLCM. The results obtained indicate that the CSA from cell line conditioned medium closely compares with the CSA from MLCM in terms of the populations of colony and cluster forming cells stimulated. This work was supported by a research grant from the Institut National de la Santé et de la Recherche Médicale (CRL 802620), Paris, France.  相似文献   

11.
本研究用体外细胞培养技术观察了大蒜油对人白血病细胞集落(CFu-L)及骨髓粒单细胞集落(CFu-GM)形成能力的影响。结果证明大蒜油对白血病细胞集落生长有明显的抑制作用,而相同浓度的大蒜油对正常人骨髓(BM)粒单细胞集落的形成能力亦有一定程度的抑制作用,但抑制作用较弱。  相似文献   

12.
Genetic management of nonhuman primates   总被引:2,自引:0,他引:2  
Genetic management is widely recognized as a critical component of the overall management of captive nonhuman primate colonies which produce animals for biomedical research. In this paper, we review the roles of conservation-oriented genetic management, research-oriented genetic management, genetic management at the level of taxomomic class, genetic management at the level of the population, and quantitative genetic analysis in comprehensive genetic management programs for nonhuman primate colonies. We conclude that genetic management is crucial for maintaining nonhuman primate populations suitable for genetic research on normal and disease-related phenotypes. In addition, for research programs that do not have specific genetic objectives, genetic management is essential to facilitate the selection of samples of well-matched unrelated animals for experimental purposes.  相似文献   

13.
Temporal and spatial analyses are seldom utilized in the study of colony genetic structure, but they are potentially powerful methods which can yield novel insights into the mechanisms underlying variation in breeding systems. Here we present the results of a study which incorporated both of these dimensions in an examination of genetic structure of subterranean termites in the genus Reticulitermes (primarily R. flavipes). Most colonies of this species (70%) were simple families apparently headed by outbred primary reproductives, while most of the remaining (27% of the total) colonies contained low effective numbers of moderately inbred reproductives. Mapping the spatial distribution of colony foraging sites over time revealed that despite the high colony density, the absolute foraging boundaries of most R. flavipes colonies were persistent and exclusive of other conspecific colonies, which suggests that this species is more territorial than has been implied by laboratory studies of intraspecific aggression. Nevertheless, we found a single colony (3% of all colonies) which contained the offspring of more than two unrelated reproductives. Although other studies have also described subterranean termite colonies with a similarly complex genetic composition, we demonstrate here that such colonies can form under natural conditions via the fusion of whole colonies. This study underscores how repeated sampling from individual colonies over time and space can yield information about colony spatial and genetic structure that cannot be obtained from conventional analyses or sampling methods.  相似文献   

14.
Abstract: Nonhuman primates housed in outside cages in rabies enzootic areas should be vaccinated against rabies because of the risk of exposure to rabid wildlife. This article reports that vaccination with an inactivated rabies vaccine for domestic animals induced levels of neutralizing antibodies against rabies in pigtail macaques (Macaca nemestrina) without causing adverse reactions.  相似文献   

15.
An inexpensive method for converting standard laboratory cages into colony units for housing small primate species is described.  相似文献   

16.
Error-prone rolling circle amplification (RCA) is a promising alternative to error-prone PCR for random mutagenesis. The main disadvantage of error-prone RCA is the low transformation efficiency of the DNA concatemer produced in the amplification reaction. We improved the method by introducing loxP recombination site of bacteriophage P1 Cre recombinase into the target plasmid and reducing the concatemer by Cre recombinase to plasmid-sized units, increasing the number of transformants 50-fold in non-error-prone and 13-fold in error-prone conditions. The efficiency improvement was verified by obtaining 115 ± 57 ceftazidime resistant colonies per recombined RCA reaction from randomly mutated TEM-1 β-lactamase gene library whereas only 9 ± 11 colonies were gained without recombination. Supplementation of the error-prone RCA with Cre/loxP recombination is a simple and useful tool to increase the transformable library size.  相似文献   

17.
蚁群遗传算法是在蚁群算法的基础上用遗传算法对其参数进行优化而产生的一种改进算法。把蚁群遗传算法应用于DNA序列比对上,结果表明这种新的序列比对算法是非常有效的。  相似文献   

18.
In the present study on the bumblebee Bombus terrestris, we investigated the influence of inbreeding on queen fitness by comparing diapause survival and egg-laying success of queens mated with nestmate and non-nestmate males. We then compared the early stage of colonies with or without diploid males and analysed colony characteristics to identify a factor predictive of colony outcome. Diapause survival was no different between queens mated with nestmates and non-nestmates, but in the latter case, egg-laying success was significantly higher. Queens mated with nestmates gave rise to a percentage of diploid male colonies (52.6%) compatible with brother–sister coupling. We obtained 18.6% of colonies with diploid males even from queens mated with non-nestmates, indicating that the colonies of origin were in some way related or homozygous at the sex determination loci. There was no difference in the early growth stage between colonies with or without diploid males, except in the number of workers emerging in the first brood, which was significantly higher in the latter. Among diploid male colonies, the number of workers and the male/worker ratio in the first brood was highly variable and was not a good predictor of subsequent colony growth. Out of 49 colonies with diploid males that reached full development, only 11 had a sufficient size to assume that they could survive in the field or, in a commercial breeding, to be suitable for pollination purposes.  相似文献   

19.
The number of biomaterials used in biomedical applications has rapidly increased in the past two decades. Fluorapatite (FA) is one of the inorganic constituents of bone or teeth used for hard-tissue repairs and replacements. Fluor-hydroxyapatite (FHA) is a new synthetically prepared composite that in its structure contains the same molecular concentration of OH groups and F ions. The aim of this experimental investigation was to evaluate cytotoxic, genotoxic and mutagenic effects of FHA and FA eluates on Chinese hamster V79 cells and to compare them with the effects of hydroxyapatite (HA) eluate. Cytotoxicity of the biomaterials tested was evaluated by use of the cell colony-formation assay and by direct counting of the cells in each colony. Genotoxicity was assessed by single-cell gel electrophoresis (comet assay) and mutagenicity was evaluated by the Hprt gene-mutation assay and in bacterial mutagenicity tests using Salmonella typhimurium TA100. The results show that the highest test concentrations of the biomaterials (100% and 75% eluates) induced very weak inhibition of colony growth (about 10%). On the other hand, the reduction of cell number per colony induced by these concentrations was in the range from 43% to 31%. The comet assay showed that biomaterials induced DNA breaks, which increased with increasing test concentrations in the order HA < FHA < FA. None of the biomaterials induced mutagenic effects compared with the positive control (N-methyl-N′-nitro-N-nitrosoguanidine), and DNA breakage was probably the reason for the inhibition of cell division in V79 cell colonies.  相似文献   

20.
Foraging behavior is a critical adaptation by insects to obtain appropriate nutrients from the environment for development and fitness. Bumble bees (Bombus spp.) form annual colonies which must rapidly increase their worker populations to support rearing reproductive individuals before the end of the season. Therefore, colony growth and reproduction should be dependent on the quality and quantity of pollen resources in the surrounding landscape. Our previous research found that B. impatiens foraging preferences to different plant species were shaped by pollen protein:lipid nutritional ratios (P:L), with foragers preferring pollen species with a ~5:1 P:L ratio. In this study, we placed B. impatiens colonies in three different habitats (forest, forest edge, and valley) to determine whether pollen nutritional quality collected by the colonies differed between areas that may differ in resource abundance and diversity. We found that habitat did not influence the collected pollen nutritional quality, with colonies in all three habitats collecting pollen averaging a 4:1 P:L ratio. Furthermore, there was no difference in the nutritional quality of the pollen collected by colonies that successfully reared reproductives and those that did not. We found however, that “nutritional intake,” calculated as the colony‐level intake rate of nutrient quantities (protein, lipid, and sugar), was strongly related to colony growth and reproductive output. Therefore, we conclude that B. impatiens colony performance is a function of the abundance of nutritionally appropriate floral resources in the surrounding landscape. Because we did not comprehensively evaluate the nutrition provided by the plant communities in each habitat, it remains to be determined how B. impatiens polylectic foraging strategies helps them select among the available pollen nutritional landscape in a variety of plant communities to obtain a balance of key macronutrients.  相似文献   

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