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1.
报道了云南新分布种子植物4种和4变种:多毛荛花,峨眉水东哥,广西火桐,广西梭罗树,大黄檗,工布小檗,延叶山桂花,少毛牛膝。  相似文献   

2.
A comparative analysis involving 21 mandibular metric characteristics of Martes zibellina (n = 114), M. martes (117), M. foina (110), and M. melampus (6) has been performed using a graphical method (scatter diagrams) and stepwise discriminant analysis. The best metric characteristics allowing for discrimination between the lower jaws of these species have been identified and used to plot scatter diagrams. The discriminant analysis has been conducted for three groups of characteristics, namely, those of the whole mandible, ramus ascendens, and corpus mandibulae. As a result, optimal statistical models based on the diagnostic characteristics have been constructed and tested. The corresponding classification functions for species identification of whole mandibles and their fragments have been calculated. These results can be used for species identification of the mandibles of M. zibellina, M. martes, M. foina, and M. melampus.  相似文献   

3.
从水东哥科植物锥序蜜心果( Saurauia napaulensis )中分离得到8个三萜类化合物,其中一个为新的三萜,鉴定其结构为2α, 3α, 24-三羟基-12-熊果烯-23-醛-28-酸.  相似文献   

4.
Tissue culture responses to three levels of NaCl (0, 85mM and 170 mM) were evaluated in several Medicago species including: M. dzhawakhetica, M. marina, M. rhodopea, M. rupestris, M. sativa (alfalfa) and M. suffruticosa. The whole plant responses of the same genotypes were evaluated in half-strength Hoagland's solution containing 0, 51.5, and 103 mM NaCl. One or more genotypes of M. dzhawakhetica, M. rhodopea, M. rupestris, and M. sativa exhibited in vitro NaCl tolerance at 85 mM. In addition, one genotype each of M. dzhawakhetica, M. rhodopea, and M. sativa was tolerant of 170 mM NaCl. However, all of the genotypes that demonstrated NaCl tolerance in vitro were NaCl sensitive at the whole plant level. Conversely, M. marina the only species exhibiting whole plant NaCl tolerance, had the most NaCl sensitive genotypes at the in vitro level. Although an in vitro NaCl tolerance mechanism which confers whole plant NaCl tolerance was not observed, a potential NaCl tolerance germplasm source, M. marina, was identified.  相似文献   

5.
A recent analysis of group A Streptococcus (GAS) invasive infections in Australia has shown a predominance of M4 GAS, a serotype recently reported to lack the antiphagocytic hyaluronic acid (HA) capsule. Here, we use molecular genetics and bioinformatics techniques to characterize 17 clinical M4 isolates associated with invasive disease in children during this recent epidemiology. All M4 isolates lacked HA capsule, and whole genome sequence analysis of two isolates revealed the complete absence of the hasABC capsule biosynthesis operon. Conversely, M4 isolates possess a functional HA-degrading hyaluronate lyase (HylA) enzyme that is rendered nonfunctional in other GAS through a point mutation. Transformation with a plasmid expressing hasABC restored partial encapsulation in wild-type (WT) M4 GAS, and full encapsulation in an isogenic M4 mutant lacking HylA. However, partial encapsulation reduced binding to human complement regulatory protein C4BP, did not enhance survival in whole human blood, and did not increase virulence of WT M4 GAS in a mouse model of systemic infection. Bioinformatics analysis found no hasABC homologs in closely related species, suggesting that this operon was a recent acquisition. These data showcase a mutually exclusive interaction of HA capsule and active HylA among strains of this leading human pathogen.  相似文献   

6.
Twelve species of Mallomonas and ten species of other genera of Mallomonadaceae and Paraphysomonadaceae were found in sediments deposited in Hall Lake from about 1850 to the present. One Mallomonas species ( M. portue-ferreae peterfi & As-mund) was found that had not previously been reported from North America. The majority of the species have been described as either generally distributed or characteristic of acid or oligotrophic humic waters. M. heterospina Lund and M. multiunca Asmund, which were restricted to sediments deposited during the operation of a sawmill on the lake, have been collected from very eutrophic to dystrophic waters as well. On the whole the species composition indicates a change in the lake from oligotrophic to more eutrophic conditions.  相似文献   

7.
Interspecific variability of the isotypic structure of two macroglobulins (Lpm and alpha 2M) in Mustelidae family was investigated using monospecific rabbit antisera against Lpm and alpha 2M Mustela vison. It was established that all the species studied may be divided into four groups, according to the degree of their homology with Lpm: 1) M. vison; 2) M. altaica, M. erminea, Kolonocus sibirica, Putorius eversmany, P. putorius, Luteola lutreola; 3) Vormela peregusna; 4) Martes martes, M. foina, M. zibellina. The greatest divergence of Martes gene species from M. vison and other species studied is determined by two different immunogenetic approaches, the first based on the whole isotype of Lpm and the other using allotypic markers of individual Lpm genes. The variability of the isotypic structure of alpha 2M was lower than that revealed in Lpm. V. peregusna is the only species which significantly differs from all above-mentioned species, including M. vison. The differences established for degree of variability between Lpm and alpha 2M in Mustelidae family may be connected with the evolutionary peculiarities of these two genetic system of serum alpha-macroglobulins, which being phylogenetically related, are still structurally divergent.  相似文献   

8.
Sulfur amino acids [cysteine (Cys) and methionine (Met)] play two major roles during animal development: protein synthesis for growth and glutathione synthesis for defense. For caterpillars, the levels of sulfur amino acids found in foliar protein can be especially low relative to their nutritional needs. Previous work has measured concentrations of glutathione (GSH; containing Cys) in specific animal tissues, but has not examined whole‐body levels to ascertain the costliness of this defense in terms of Cys allocation. This study examined whether the production of GSH varies between species and within individuals in accordance with an insect's need for antioxidant defense. Secondly, we quantified the allocation of total Cys (peptide‐bound plus free Cys) to GSH in caterpillars as an estimate of its cost. Two contrasting species were compared: Lymantria dispar (Lymantriidae), a species that is highly defended, and Malacosoma disstria (Lasiocampidae), a species that is less defended. As expected, GSH levels were significantly higher in L. dispar than in M. disstria. Consistent with the function of the midgut as a first line of defense against ingested toxins, GSH levels were significantly higher in these tissues than in the whole bodies of both species. A major finding in this study was that a large fraction of total Cys is used to produce GSH: GSH in the midguts of L. dispar and M. disstria contained 23 and 21%, respectively, of the total Cys in these tissues, and the GSH in their remaining body tissues contained 19 and 17% of the total Cys in these tissues. Levels of total Cys in caterpillar tissues followed the same pattern of distribution as did GSH, producing a strong association between GSH and total Cys (R2 = 0.794). We conclude that GSH is a costly defense, especially in generalist tree‐feeding species such as L. dispar. These results further suggest that the large allocation of Cys to GSH in highly defended species might produce a tradeoff by limiting the amount of Cys available for rapid growth.  相似文献   

9.
Cytosolic progesterone receptors (PRcs) from the reproductive tract of the female turkey were analyzed by high-performance liquid chromatography using a diethylaminoethyl (DEAE) ion-exchange column. PRcs from oviduct tissue of laying, incubating, photorefractory and short-day turkey hens were compared. In general, three types of PRcs were identified: Receptor I, a partially displaceable species that was eluted at a 0.13 M salt concentration; and Receptors II and III, which were two specific binding species eluting at 0.23 M and 0.26 M, respectively. In the subdivided tissue from the laying hen oviduct, Receptor I was the major PRc species of the isthmus and Receptor III was the only receptor present in the uterus. The infundibulum and magnum each contained a small amount of Receptor II and a substantial amount of Receptor III. The whole oviduct of incubating hens contained a greater proportion of Receptor I than Receptor II or III, and these last two receptor types were present in equal quantity. The whole oviduct of the short-day hens had an equal distribution of the three receptor types. In the presence of sodium molybdate, an inhibitor of phosphatase and protease, only one sharp Receptor II species was seen in the magnum and uterus of the laying hen oviduct and in the whole oviducts of incubating and short-day hens. The transformation of Receptor II to Receptor III in the absence of sodium molybdate was facilitated by the aging of cytosol at 0-4 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
The ecology and phylogeny of the Melitaeini butterflies have received considerable attention in the last few years. Several publications have been based on research using molecular methods. Genital morphometry has already been published on two sibling species but without any accompanying taxonomic revision of related species or their intraspecific taxonomy. In this study the morphology of genitalia was analysed by landmark-based geometric morphometrics in males and by traditional morphometrics in females. Based on these morphological characters, the whole M. phoebe group (subg. Cinclidia) was revised. According to our results M. telona Fruhstorfer, 1908 is conspecific with M. ‘phoebe’ ornata Christoph, 1893. Thus, we consider M. telona a junior synonym of M. ornata, and we propose new combinations: M. ornata ornata Christoph, 1893, M. ornata telona Fruhstorfer, 1908, M. ornata amanica Rebel, 1917, M. ornata capreola Varga, 1967, M. ornata emipunica Verity, 1919, M. ornata enoch Higgins, 1941, M. ornata kovacsi Varga, 1967, M. ornata nigrogygia Verity, 1938, M. ornata ogygia Fruhstorfer, 1907 and M. ornata totila Stauder, 1914 based on the rule of priority. The validity of the species status of M. punica and M. scotosia was confirmed, whereas M. sibina and M. pseudosibina could not be separated from M. phoebe using morphometrics. A new species from Iran (Zagros Mts.) was described as M. zagrosi sp. n. In addition, the whole geographical range of M. ornata was reconsidered and some biogeographical connections were discussed. In M. ornata four morphotypes were found based on genitalia: 1. ‘Western type’: including the Italian, Hungarian and SW Ukrainian populations; 2. ‘Eastern type’: with a much extended distribution ranging from the Balkan Peninsula through Asia Minor to Kazakhstan; 3. ‘The Levant type’ (=M. ornata telona comb. nov.); 4. ‘Northern Iranian type’ (Kopeth Dagh and Elburz Mts.). The distribution of these morphotypes can be attributed to historic separation in distinct glacial refugia.  相似文献   

11.
鹿科动物线粒体控制区序列分析与系统进化   总被引:6,自引:0,他引:6  
通过测定鹿科麂亚科中的小麂、赤麂和黑麂的线粒体全基因组,从而定位它们的控制区,并从GenBank获得鹿科另外3个亚科9种动物的线粒体控制区全序列。利用MEGA软件计算了各物种控制区序列的碱基组成、遗传距离和遗传相似度,通过比较序列同源性,以羊线粒体控制区序列为外群,构建NJ分子系统树,探讨了鹿科4个亚科12种动物的系统进化关系。序列分析表明,鹿科12种动物控制区序列的碱基长度在909~1049bp之间,A T含量约占62.06%,其中363个核苷酸位点存在变异(约占34%)。系统进化关系结果表明:(1)以线粒体控制区构建的鹿科12种动物分子系统树基本与NCBI分类一致;(2)美洲鹿亚科驼鹿属驼鹿在鹿科这12种动物中处于最为原始的地位;(3)小麂比赤麂和黑麂更为原始;(4)獐亚科獐属的獐与美洲鹿亚科狍鹿属的狍鹿和美洲狍鹿聚为一支。  相似文献   

12.
Eastern cottontail (Sylvilagus floridanus, fam. Leporidae), introduced into Piedmont (Italy) in the 1960s, was studied as carrier of dermatophyte fungi. Of 216 hair samples collected from animals culled between September 1999 and July 2000 in the Province of Alessandria (Piedmont, Italy) during a pest control project, 57 (26.4%) yielded dermatophyte colonies. As two different species of dermatophytes grew from two samples, a total of 59 fungal isolates (26.5%) were obtained. Six dermatophyte species both geophilic (M. gypseum, M. cookei, Trichophyton ajelloi, T. terrestre) and zoophilic (M. canis, T. mentagrophytes) were identified. No sex-related differences were found but season-related differences were observed. The highest prevalence of dermatophyte-positive samples was recorded in May–September, due to the geophilic fungi whose prevalence decreased during colder and increased during warmer months ( p < 0.001). The presence of zoophilic dermatophytes, T. mentagrophytes, commonly associated with rodents, small mammals and lagomorphs and M. canis, usually correlated with domestic environment, did not change the whole year round. As Eastern cottontail has been showed to be a carrier of dermatophytes transmissible to man (M. canis, T. mentagrophytes and M. gypseum), it may represent a source of infection for gamekeepers, hunters and veterinarians.  相似文献   

13.
Allozyme electrophoresis was used to compare specimens of Labiostrongylus (Labiosimplex) bancrofti from two species of Australian macropodids, Macropus dorsalis and M. parryi, with a related species, L. (Labiomultiplex) uncinatus which also infests M. dorsalis. Each nematode was characterised genetically at 18 enzyme loci. The level of fixed genetic differences detected between L. (Ls.) bancrofti from M. parryi and M. dorsalis (83%) is equivalent to that when each is compared to the morphologically distinct species L. (Lm.) uncinatus (89–94%), demonstrating unequivocally that the taxon L. (Ls.) bancrofti represents at least two species, one in M. parryi and one in M. dorsalis. In addition, morphological evidence from additional specimens collected from M. parryi suggested the existence of a third sibling species in this group. All three species differ in the shape of the spicule tips; L. (Ls.) bancrofti has longer spicules than either of the two new species. L. (Ls.) quasibancrofti n. sp. has smaller cephalic papillae, larger oesophago-intestinal diverticula, a larger genital cone and a longer female tail than L. (Ls.) turnbulli n. sp. The taxon L. (Ls.) bancrofti consists, therefore, of three species, L. (Ls.) turnbulli in M. parryi, L. (Ls.) quasibancrofti in M. dorsalis, and L. (Ls.) bancrofti found in both host species, as well as in four species of rock wallabies.  相似文献   

14.
ABSTRACT. 1. Two superficially similar species of Microbembex, M.monodonta (Say) and M.cubana Bohart (Hymenoptera, Sphecidae, Nyssoninae), occur syntopically on Staniel Cay, a small Bahamian island (15 km2).
2. Nesting (female) and territorial (male) aggregations of M.cubana were smaller and more numerous than those of M.monodonta in the study site and on the island as a whole.
3. Both species had regular patterns of daily activities that required them to use a variety of microhabitats in the study area.
4. Males of both species defended territories from c. 09.00 to 12.00 hours EST (in May) and the left to feed on nectar until they retired to sleeping burrows, typically from 13.00 to 15.00 hours. Male M.monodonta were active longer each day and intermixed feeding and territorial defence more than did male M.cubana.
5. Females of both species were active for longer each day, from c. 08.30 to 15.30 hours, and intermixed their respective activities – hunting for provisions, feeding, and nest digging and maintenance – during each day more than did males. Female M.monodonta were active longer each day, rising earlier and retiring later, than female M.cubana.
6. In M.monodonta , females were larger (length, X =11.00 mm) than males (10.5 mm). In M.cubana , males were larger (11.1 mm) than females (10.4 mm). Although mean differences were small, they were highly significant ( F =22.42; P <10−4) for the species-sex interaction.
7. Differences in activity budgets, habitat use, and sexual size dimorphism appear to be related. A combination of factors, particularly thermal constraints, possible competition, and different mating systems, could explain these patterns.  相似文献   

15.
Root-knot nematodes are a major group of plant-parasitic nematodes, but their sister group within the Tylenchida remains to be identified. To find the sister group and for any investigation of the evolutionary biology of the genus Meloidogyne, it would be useful to identify the most basal species within Meloidogyninae. Meloidogyne spartinae, a root-knot nematode parasitic on cordgrass (Spartina spp.), constitutes a potentially interesting early diverging (or at least highly divergent) root-knot nematode because it was originally described in a different genus, Hypsoperine (and later Spartonema), due to its unique anatomy and biology (although it was later put in synonymy by some, but not all, taxonomists). We have sequenced the whole 18S rDNA of this species and compared it to other sequences of this region that are available in GenBank for numerous Meloidogyne species. Phylogenetic analysis unambiguously locates the branch corresponding to M. spartinae as a lately diverging species, more closely related to M. maritima, M. duytsi or the M. ardenensis-hapla group. Thus, the distinction of a separate genus (Hypsoperine or Spartonema) for this species is not justified.  相似文献   

16.
The biotopic distribution, nest structure, wintering conditions, and cold hardiness of four ecologically contrasting ant species (Myrmica angulinodis, M. kamtschatica, M. bicolor, and M. transsibirica) are considered. The cold hardiness of these species is typical of the genus: the supercooling points vary from −28 to −31°C; cold hardiness levels (LT50%) are higher by 5°C. At this level of cold hardiness, ants can be practically ubiquitous across the whole Hypoarctic (Berman et al., 2007). However, the above Myrmica species are strictly segregated (M. kamtschatica occurs in moss bogs, M. angulinodis and M. transsibirica, on dry and warm south slopes, and M. bicolor, in sandy-gravel floodplains), probably due to different requirements for weather conditions in summer and depth of ground thawing. At present, the excess cold hardiness common to the species in question (exceeding the nest temperature by 5–10°C in different years) is not adaptive and may be considered as preadaptive. It could have been acquired during ancient cold epochs or inherited by the genus as a concomitant result of adaptation not to low temperatures but, for instance, to aridity. These Myrmica species do not undergo selection for resistance to negative temperatures since their current level of cold hardiness is excessive, considering the possible wintering temperatures.  相似文献   

17.
We investigated how fungal decomposer (aquatic hyphomycetes) communities colonizing alder and eucalyptus leaf litter respond to changes in habitat characteristics (transplantation experiment). We examined the breakdown of leaf materials and the associated fungal communities at two contrasting sites, a headwater stream (H) and a midreach (M). Agroforestry increased from headwater to midreach. One month after the start of experiments at both sites, some leaf samples from the midreach site were transplanted to the headwater site (M–H treatment). Although both sites showed similar dissolved inorganic nutrient concentrations, eucalyptus leaves initially incubated at the midreach site (M, M–H) increased their breakdown rate compared to those incubated along the experiment at the headwater site (H). Alder breakdown rate was not enhanced, suggesting that their consumption was not limited by nutrient availability. Sporulation rates clearly differed between leaf types (alder > eucalyptus) and streams (H > M), but no transplantation effect was detected. When comparing conidial assemblages after transplantation, an inoculum effect (persistence of early colonizing species) was clear in both leaf species. Substrate preference and shifts in the relative importance of some fungal species along the process were also observed. Overall, our results support the determining role of the initial conditioning phase on the whole litter breakdown process, highlighting the importance of intrinsic leaf characteristics and those of the incubation habitat.  相似文献   

18.
本文报道1963年4—5月和10—11月两度在东湖101个采样点上进行软体动物定量采集的结果。软体动物计41种,隶10科、20属,其中腹足类的种类多,生物量也大,瓣鳃类则全系小型种类主要为河蚬(Corbicula fluminea),个体数及生物量都很低。根据10—11月的调查结果,全湖软体动物平均生物量为30.5克/平方米(平均个体数为134个/平方米),其中以铜锈环稜螺(Bellamya aerginosa)生物量最大(15.5克),其次为纹沼螺(Parafossarudus striatulus)(5.8克)和长角涵螺(Alocinma longicornis)(6.4克),这3种腹足类占全部软体动物生物量的90%以上,是东湖中的优势种类。它们的分布型式属大小不等的核心分布,其实际分布概率,符合P-E 分布的理论概率。环境分析表明铜锈环稜螺的分布主要取决于水深(r=-0.257;d.f.=99;p0.01);长角涵螺数量的多寡受制于水草的有无(均数比较:d.f.=99时,t′=7.656;t0.01≈2.641);而纹沼螺的分布则与水深有关(r=-0.697;d.f.=99;p0.01),又与水草的有无有关(平均数比较:d.f.=99时,t′=6.93;t0.01≈2.641)。    相似文献   

19.
This study was designed to monitor the presence of Mycoplasma agalactiae and Mycoplasma mycoides subsp. capri (Mmc) in 66 dairy goat herds of a genetic improvement programme in a region of Spain where contagious agalactia is endemic. Over a whole lactation period, 300 bulk tank milk and 381 milk samples from goats with clinical mastitis were subjected to polymerase chain reaction (PCR) to detect the two mycoplasma species. The presence of mycoplasmas (either species or both) was detected in 66.7% of the herds and M. agalactiae was identified in 95.45% of these positives herds. In a given infected herd, mycoplasmas were not continuously detected over the whole study period. Our findings indicate that in an endemic area, M. agalactiae and Mmc can be monitored through PCR analysis of mastitic milk and bulk tank milk (BTM) samples. Over a lactation period we recommend testing multiple BTM samples on a herd. No relationship was observed between the use of inactivated mycoplasma vaccines and the PCR detection of both mycoplasmas.  相似文献   

20.
ABSTRACT. Anopheles stephensi Liston, Anopheles freeborni Aitken, Anopheles gambiae Giles and Anopheles dirus (Peyton & Harrison) fed equally well on whole blood, red blood cells, platelet-rich plasma and platelet-poor plasma. Similar feeding ability on 0.15 M NaCl containing 10-2 M NaHCO3 was shown by the first three species, but An. dirus required an addition of albumin. The need for ATP as a phagostimulant could not be demonstrated in any of these species.  相似文献   

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