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1.
《Journal of bryology》2013,35(4):383-386
Abstract

Dicranella riparia is shown to be more appropriately treated as Kiaeria riparia comb. nov.; Kiaeria glacialis is shown to be a misfit in Dicranum; Oncophorus sardous is placed in synonymy of O. wahlenbergii; Arctoa anderssonii is shown to be a distinct species.  相似文献   

2.
The genomic constitutions of Roegneria alashanica, R. elytrigioides, R. magnicaespes and R. grandis were studied using GISH. DNA of Pseudoroegneria spicata (St), P. libanotica (St), P. stipifolia (St), R. ciliaris (StY), Lopophyllum elongatum (Ee), Agropyron cristatum (P) and Hordeum bogdanii (H) were used for probing, respectively. The results indicated that: 1) R. alashanica and R. magnicaespes contained one St genome, the other genome was unidentified, however, it was not an E, P, H or Y genome; 2) R. elytrigioides contained two St genomes and should on this basis be included in Pseudoroegneria; 3) R. grandis contained an St and an Stg genome. The Stg genome is suggested to be a modified form of the St genome of Pseudoroegneria and to be homoeologous with the Y genome. It might be an intermediate type between the St and Y genomes. Therefore, R. elytrigioides should be treated as Pseudoroegneriaelytrigioides.Roegneria alashanica, R. magnicaespes and R. grandis does apparently not belong in the genus Roegneria but further studies are needed to establish their correct taxonomic position.  相似文献   

3.
The estimator ?0(x) of the regression r(x) = E (Y | × = x) from measured points (xi, yi), i = 1(1) n, of a continuous two-dimensional random variable (X, Y) with unknown continuous density function f(x, y) and with moments up to the second order can be made with the help of a density estimation f?0(x, y) (see e.g. SCHMERLING and PEIL, 1980). Here f?0(x, y) still contains free parameters (so-called band-width-parameters), the values of which have to be optimally fixed in the concrete case. This fixing can be done by using a modification of the maximum-likelihood principle including jackknife techniques. The parameter values can be also found from the estimators for r(x). Here the cross-validation principle can be applied. Some numerical aspects of these possibilities for optimally fixing the bandwidth-parameter are discussed by means of examples. If ?0(x) is used as a smoothing operator for time series the optimal choice of the parameter values is dependent on the purpose of application of the smoothed time series. The fixing will then be done by considering the so-called filter-characteristic of ?C0(x).  相似文献   

4.
The effects of 60 Hz magnetic fields of 5 μT (50 mG) or less on biological structures holding magnetite (Fe3O4) are shown to be much smaller than that from thermal agitation; hence such interactions cannot be expected to be biologically significant. © 1993 Wiley-Liss, Inc.  相似文献   

5.
Abstract Phylogenetic analysis of Saltusaphidinae (Homoptera: Aphidoidea: Drepanosiphidae) was made by using 10 generic, 17 adult and 2 embryo characters. The results suggest alternative hypotheses: (1) Allaphis should be a subgenus of Thripsaphis; (2) Peltaphis should be an independent genus; (3) Stenaphis should be a subgenus of Subsaltusaphis; (4) monophyly of Sminthuraphis; and (5) phylogenetic relationships of Neveskyella, Subsaltusaphis, Saltusaphis and Iziphya. In order to resolve the argued position of Macropodaphis Remaudiere and Davatchi, 1958, Phyllaphidinae, Saltusaphidinae and Macropodaphis were taken as in-group members, 6 morphological characters and host-plant character were used. The result shows that Macropodaphis should be in a new subfamily Macropodaphidinae, and Macropodaphidinae and Saltusaphidinae should be sister groups.  相似文献   

6.
The two generaPlectranthus andIsodon are compared and found to be very dissimilar.Isodon ist considered to be misplaced inOcimeae subtribePlectranthinae and apparently is more closely related to subtribeHyptidinae. The disjunct genusRabdosiella is compared to these two genera and regarded to be polyphyletic. The AfricanR. calycina (Benth.)Codd is returned toPlectranthus and calledP. calycinus Benth., while the AsianR. ternifolia (D. Don)Codd is placed inIsodon sect.Pyramidium and calledI. ternifolius (D. Don)Kudo.  相似文献   

7.
If X1, X2, denote the random variables of measurement under two treatments then the probability P (X1X2) is a quantity of great practical interest, especially if we consider both to be measured for the same unity. In this case the random variables cannot be assumed to be independent any longer. The following paper describes a procedure to compute approximate confidence bounds for P (X1X2) where correlations between X1, X2 are admitted as well as between replications of the Xj. There is some relation to the FRIEDMAN-statistic with or without repeated measurements and as a special case to the sign-test. Application may be extended to ordinal data.  相似文献   

8.
A B10.S(7R) anti-B10.S(9R) serum (anti-IJE k C d ) contained, as expected, antibodies specific for the I-E-subregion-encoded determinant Ia.7. However, tests on recombinant haplotypes demonstrated a series of unexpected weak extrareactions which could be interpreted to be directed against antigenic determinants encoded in the I-A subregion of the H-2 complex. The same type of extrareaction was observed in eluates from I-A s , I-E k cells coated with A.TH anti-A.TL (I-A s , I-E s anti-I-A k , I-E k ) serum. This reactivity in serum and eluates could be interpreted as cross-reactivity between products of the I-E and I-A subregions.  相似文献   

9.
The dose-response of an individual organism can be described by a step functions if the organism survives when the dose is below a certain lethal level and dies when this level is exceeded. If, in a population of organism, the lethal dose for an individual has a unimodal distribution, the latter's properties will determine the shape of the population's response in the following manner. If the distribution is symmetric the dose-response curve has a symmetric sigmoid shape when plotted on linear coordinates. The location of the inflection point and the curve's slope around it are determined by the distribution's mode and variance. When the distribution is skewed, the dose-response curve has an asymmetric sigmoid shape which becomes reminiscent of an exponential decay when the distribution is strongly skewed to the right. The population's dose-response curve can be constructed by integration of the step changes over the distribution range. The step function representing the dose-response of an individual organism can be approximate by a Fermi function, and the distribution of an lethal doses can be represented by the Weibull distribution function. When the two functions are combined, the resulting dose-response of the populationS(X)), which is the fraction of survivors after exposure to a doseX, is given by:S(X)=∫ 0 1 [1/{+exp{(X-X c (φ))/a i ]}] whereX c (ω)={(1/b)[-ln(1-ω)]}(1/n),n andb being the constants of the Weibull distribution anda i an arbitrarily small number, i.e.a i ≪[X−X c (ϕ)], whose actual magnitude is of little significance. This model can be used to determine the underlying distributions of experimental dose-response relationship. It was applied to published survival data of microorganisms exposed to pulsed electric field, X-ray radiation and ozone to show that the different observed shapes of the dose-response curve, and shifts between them, can be expressed in terms of the correponding distribution parameters, namely the mode, variance and skewness.  相似文献   

10.
In this work it is demonstrated that the characterization of c-type haem containing proteins by electrochemical techniques needs to be cautiously performed when using pyrolytic graphite electrodes. An altered form of the cytochromes, which has a redox potential 300 mV lower than that of the native state and displays peroxidatic activity, can be induced by interaction with the pyrolytic graphite electrode. Proper control experiments need to be performed, as altered conformations of the enzymes containing c-type haems can show activity towards the enzyme substrate. The work was focused on the study of the activation mechanism and catalytic activity of cytochrome c peroxidase from Paracoccus pantotrophus. The results could only be interpreted with the assignment of the observed non-turnover and catalytic signals to a non-native conformation state of the electron-transferring haem. The same phenomenon was detected for Met–His monohaem cytochromes (mitochondrial cytochrome c and Desulfovibrio vulgaris cytochrome c-553), as well as for the bis-His multihaem cytochrome c 3 from Desulfovibrio gigas, showing that this effect is independent of the axial coordination of the c-type haem protein. Thus, the interpretation of electrochemical signals of c-type (multi)haem proteins at pyrolytic graphite electrodes must be carefully performed, to avoid misassignment of the signals and incorrect interpretation of catalytic intermediates.  相似文献   

11.
Gypsy is an endogenous retrovirus present in the genome of Drosophila melanogaster. This element is mobilized only in the progeny of females which contain active gypsy elements and which are homozygous for permissive alleles of a host gene called flamenco (flam). Some data strongly suggest that gypsy elements bearing a diagnostic HindIII site in the central region of the retrovirus body represent a subfamily that appears to be much more active than elements devoid of this site. We have taken advantage of this structural difference to assess by the Southern blotting technique the genomic distribution of active gypsy elements. In some of the laboratory Drosophila stocks tested, active gypsy elements were found to be restricted to the Y chromosome. Further analyses of 14 strains tested for the permissive vs. restrictive status of their flamenco alleles suggest that the presence of permissive alleles of flam in a stock tends to be associated with the confinement of active gypsy elements to the Y chromosome. This might be the result of the female-specific effect of flamenco on gypsy activity. Received: 13 June 1997 / Accepted: 27 August 1997  相似文献   

12.
Aims: Ste15 and ste22 present in the Ebosin biosynthesis gene cluster (ste) were previously shown to function in Ebosin biosynthesis and both of the protein products are predicted to be glycosyltransferases. In this study, their biochemical activities were confirmed. Methods and Results: ste15 and ste22 were cloned and expressed in Escherichia coli. With a continuous coupled spectrophotometric assay and using the purified proteins, we now demonstrated that the protein Ste15 has the ability of catalysing the transfer of glucose specifically from UDP‐glucose to an Ebosin precursor that lacks glucose, the lipid carrier located in the cytoplasmic membrane of the gene ste15 disrupt mutant Streptomyces sp. 139 (ste15?). The protein Ste22 can catalyse the transfer of rhamnose specifically from TDP‐rhamnose to an Ebosin precursor that lacks rhamnose, a lipophilic carrier in the cytoplasmic membrane of the gene ste22 disrupt mutant Streptomyces sp. 139 (ste22?). Conclusions: The gene product of ste15 was identified to be a glucosyltransferase, and the protein encoded by ste22 was found to be a rhamnosyltransferase. Significance and Impact of the Study: Both of two enzymes play essential roles in the formation of repeating units of sugars during Ebosin biosynthesis. These are the first glucosyltransferase and rhamnosyltransferase in the biosynthesis of a Streptomyces exopolysaccharide to be characterized.  相似文献   

13.
《西北植物学报》2014,(12):43-45
目的 了解医院门诊退费概况,构建减少退费作业的合理对策。方法 借助门诊就诊流程图与退费记录信息,剖析退费原因。结果 退费原因众多,多个作业流程存在待规范事项。结论 针对具体作业流程构建合理对策,尽最大可能减少退费作业,节约时间成本,提高服务患者能力及水平。  相似文献   

14.
DNA probes were used to identify restriction-fragment-length polymorphisms (RFLPs) in DNA samples, demonstrating that the Mycobacterium avium complex could be clearly divided Into M. avium and Mycobacterium intracellulare strains. Less than 2% DNA base substitution was found between M. avium strains, whereas the M. intracellulare strains had greater than 15% base substitution. The Johne's disease bacillus, Mycobacterium paratubercuiosis (American type strain), was found to be distinguishable from the M. avium complex serotypes examined. Strain 18 was found to be identical to M. avium. The rat leprosy bacillus, Mycobacterium lepraemurium, was found to be very closely related, but not identical, to M. avium.  相似文献   

15.
目的 分析某省级三甲医院对《江苏省基本医疗保险药品目录》的执行效果。方法 选取江苏省某省级三级医院为研究对象,比较分析城镇职工医保患者和自费患者的药品使用情况。结果 新版《医保药品目录》能基本满足该院临床治疗需求;对门诊医保患者费用控制具有显著作用,但对住院医保患者的药品费用控制效果不明显,对不同疾病药品费用控制效果不一。结论 建立和完善严格的用药考核制度,需加强中高档药物使用的监管,并增加相应的适应症限制,应考虑将临床治疗可供选择、药价适应的药品纳入目录。  相似文献   

16.
NADP+-dependent aminoalcohol dehydrogenase (AADH) of Rhodococcus erythropolis MAK154 produces double chiral aminoalcohols, which are used as pharmaceuticals. However, the genetic manipulation of Rhodococcus strains to increase their production of such industrially important enzymes is not well studied. Therefore, I aimed to construct Rhodococcus expression vectors, derived from the RhodococcusEscherichia coli shuttle vector pRET1102, to express aadh. The plasmid pRET1102 could be transformed into many actinomycete strains, including R. erythropolis. The transformation ef?ciency for a species closely related to R. erythropolis was higher than that for other actinomycete strains. Promoters of various strengths, hsp, 1200rep, and TRR, were obtained from Gram-positive bacteria. The activity of TRR was stronger than that of hsp and 1200rep. The aadh-expressing plasmid pRET1172 with TRR could be transformed into many actinomycete strains to increase their AADH production. The Rhodococcus expression vector, pRET11100, constructed by removing aadh from the pRET1172 plasmid may be useful for bioconversion.  相似文献   

17.
The type specimens of the ichnospecies Haplotichnus indianensis and Treptichnus bifurcus were compared under low-angle light. H. indianensis was found to exhibit segments with projections, which are morphological characteristics of T. bifurcus. Consequently, H. indianensis is reinterpreted here as a shallow, subsurface burrow and is considered to be a subjective junior synonym of T. bifurcus. Traces assigned to H. indianensis, other than the type, should be reassigned to other ichnotaxa. Looping surface trails, for example, should be called Gordia isp.  相似文献   

18.
Vernalization requirement is an important trait in temperate crop plants such as wheat and must be considered when selecting varieties for cultivation under different climatic conditions. To determine the growth habit of wheat varieties, plants need to be grown under different vernalization regimes, a lengthy but necessary process for breeders involved in crossing winter with spring germplasm. If haplotypes can be associated with growth habit, then molecular marker assays that are reliable, cheap, and quick can be developed to assist in the selection of plants with the desired phenotype. We have analyzed 81 accessions that have different vernalization requirements and putative different origins of spring habit for sequence variation at the Apetala1 (AP1) locus, which underlies Vrn-1, and at the linked Phytochrome C (PhyC) locus. Good correspondence was found between the AP1 genotype and the PhyC haplotype for 77 of the 81 accessions. Two varieties displayed a recombination event between the AP1 and PhyC loci, and one variety carried a recombinant PhyC gene. In addition, one variety carried an apparent AP1 winter allele, but displayed the Vrn-A1 spring habit. The PhyC haplotype for this variety also indicated the presence of a Vrn-A1 spring allele. Our data suggest that both the AP1 promoter region and PhyC SNPs can be used as diagnostic markers for vernalization response at the vrn-A1 locus, but that neither are perfect tags.  相似文献   

19.
This paper refers to a case of polymorphism in the desmid genus Xanthidium Ehr. It is based on material from Lake Dais Irmaios, the main body of water in the Zoological and Botanical Garden in Recife, Pernambuco, northeastern Brazil, collected at 4 different times of the year during 1967 and 1968. A detailed examination of almost 1300 specimens showed an enormous variety in form of Xanthidium regulare Nordst., X. fragile Borge, and X. pseudoregulare Borge, thus allowing the authors to draw the following conclusions: (1) the name X. regulare Nordst. should be retained until further and more detailed studies on form variation within the species are available; (2) the names X. regulare Nordst. var. asteptum Nordst. in Borge, X. regulare Nordst. var. sexangulare Grönbl., X. regulare Nordst. var. sexangulare Grönbl. f. robustior Grönbl., X. fragile Borge, X. fragile Borge forma, and X. fragile Borge var. depauperatum Borge should be considered synonymous, all referring to a single variety of X. regulare Nordst., var. asteptum Nordst. in Borge emend. C. Bic. & L. M. Carv.; (3) X. pseudoregulare Borge must be treated as a variety of X. regulare Nordst. and must be called X. regulare Nordst. var. pseudoregulare (Barge) C. Bic. & L. M. Carv. Finally, a key is given to the 3 varieties of X. regulare Nordst. proposed in the present paper.  相似文献   

20.
Parataenia Linton cannot exist as a cestode genus as it is preoccupied. Discobothrium van Beneden is not a junior synonym of Echeneibothrium van Beneden, and Hornellobothrium Shipley & Hornell and Eniochobothrium Shipley & Hornell are very likely not junior synonyms of Discobothrium. Hexacanalis Perrenoud should be considered a junior synonym of Cephalobothrium Shipley & Hornell. Yogeshwaria Chincholikar & Shinde, Spinocephalum Deshmukh and Flapocephalus Deshmukh are considered unrecognisable. Staurobothrium Shipley & Hornell should be returned to the Phyllobothriidae. Balanobothrium Hornell should remain in the Onchobothriidae Braun. The order Lecanicephalidea was not established by Baylis. There are no grounds for recognising the superfamily Lecanicephaloidea Southwell which contains only the Lecanicephalidae Braun. The elevation of the lecanicephalids to an order, the Lecanicephala, does not appear to be valid. To avoid further confusion the scheme set out by Braun (1900) should be used as a basis for classification of the lecanicephalids.  相似文献   

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