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71.
72.
COLIN M. SHARPLES JOHN E. FA DIANA J. BELL 《Zoological Journal of the Linnean Society》1996,117(2):141-158
Craniometric data of nine characters from 260 skulls of Oryctolagus cuniculus from western Europe and northern Africa were gathered to examine phenotypic variation in size, using both univariate and multivariate analyses. Although animals from the northern part of Europe were found to be larger than those from southern Europe, variation in size occurred in a continuous cline. Skull size was positively correlated with latitude and negatively correlated with ambient temperature. On the basis of skull morphology, there is no evidence for separation of O. cuniculus into the two or more subspecies commonly described. Further data, particularly from genetic material, are required to clarify the taxonomic status of the rabbit in Europe. 相似文献
73.
I V Bazov T P Kazubskaia V D Ermilova R F Gar'kavtseva V I Loginov E R Zabarovski? E A Braga 《Molekuliarnaia biologiia》2001,35(3):404-412
Allelic deletions along the short arm of human chromosome 3 were mapped in 57 pairs of DNA samples from tumor and normal tissue of renal carcinoma patients in order to locate potential tumor suppressor genes. Twenty highly polymorphic microsatellite markers were used for deletion mapping. Allelic deletions were found in most of the samples (91%). Extended terminal deletions (56%) prevailed over shorter internal and multiple deletions and dominated (65%) in the most aggressive histopathological kidney cancer subtype, clear-cell carcinoma. Frequency analysis of loss of heterozygosity allowed detection of the human chromosome 3 regions most essential for renal carcinomas: the region adjacent to the gene VHL (3p26-p25), the region of homozygous deletions AP20 (3p22-p21.33), and a new region between markers D3S2420 and D3S2409 (3p21.31, 2.2 Mbp). 相似文献
74.
Upper Hauterivian reefal carbonates of the Llàcova Formation (Maestrat Basin, Iberian Chain, E Spain) contain Sporolithon phylloideum (Bucur and Dragastan) Tomás, Aguirre, Braga and Martín-Closas comb. nov. and Sporolithon rude (Lemoine) Ghosh and Maithy (1996). Moussavian et al. (1993) identified them as Parakymalithon phylloideum (Bucur and Dragastan) Moussavian 1987 and Archaeolithothamnium rude Lemoine 1925. The re-assessment of the type of P. phylloideum and additional material indicate that the diagnostic characters of the genus do not warrant separation from Sporolithon and the new combination Sporolithon phylloideum is proposed. The lectotype of Sporolithon rude presents sporangial cavities grouped in sori that can be merged originating a structure that resembles the multiporate tetrasporangial
conceptacles of the Hapalidiaceae. We hypothesize that multiporate tetrasporangial conceptacles could have originated from
the fusion of several sporangial cavities, suggesting a phylogenetic linkage between Sporolithaceae and Hapalidiaceae supported
by other anatomical features, molecular phylogeny and the fossil record. 相似文献
75.
Anderson S. Dias Jackson V. Araújo Artur K. Campos Fabio R. Braga Thiago A. Fonseca 《World journal of microbiology & biotechnology》2007,23(9):1245-1252
The viability of a formulation of Duddingtonia flagrans was assessed in the control of parasite gastrointestinal nematodes of cattle. Two groups (A and B) of eight crossbred Holstein × Zebu
cattle, approximately one year old, were placed in Brachiaria decumbens pasture. Each animal in group B (treated) received orally 20 g sodium alginate pellets containing mycelial mass of the D. flagrans fungus, while the animals in the group A (control) received pellets without fungus for seven months, starting in March 2005.
The egg per gram of feces counting the gastrointestinal nematodes showed a difference (P < 0.05) in the treated group in June, July and August, with reductions of 58% (June), 47% (July) and 51% (August) compared
to the control group. The infective larvae recovered in the pastures collected up to 20 cm from distance of the fecal dung
in group B differed (P < 0.01) from the larvae recovered in group A. At the end of the experimental period, the animals in group B presented a greater
weight gain (P < 0.01) compared to the untreated group (A). The treatment of cattle with pellets containing the D. flagrans nematophagous fungus, at the dose and duration used was effective in controlling the infective larvae of gastrointestinal
nematodes of cattle. 相似文献
76.
Luenga-Caicedo PE Braga FC Brandão GC Braga de Oliveira A 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(9-10):701-709
Cecropia glaziovi Sneth. (syn. C. glaziovii, C. glazioui) (Cecropiaceae) is a South American medicinal plant whose antihypertensive activity is attributed to its flavonoid and proanthocyanidin contents. The seasonal and intraspecific variations of these two classes of compounds in C. glaziovi leaves were assayed by spectrophotometry in samples of young and mature leaves collected from native, cultivated and micropropagated trees in the dry and rainy periods of the year. The total flavonoid and proanthocyanidin contents ranged from (0.64 +/- 0.21)% to (3.44 +/- 0.45)% and (2.23 +/- 0.92)% to (5.36 +/- 0.95)%, respectively, among the assayed populations. The flavonoid contents in native plants did not differ statistically between young and mature leaves within the same season, whereas it was higher in both young and mature leaves collected in the dry compared to those collected in the rainy period. For cultivated specimens, the results pointed to higher contents in the dry season, whereas no significant difference was observed for leaves of micropropagated (clone) plants collected in both periods. For the assayed populations, higher proanthocyanidin contents were found in the dry season, excepting the micropropagated (clone) plants, whose contents did not differ significantly between the dry and the rainy periods. Leaves of micropropagated (clone) and cultivated specimens showed less intraspecific variation in the flavonoid and proanthocyanidin contents than those from native trees. These features suggest that, as expected, cultivation of C. glaziovi is of great interest providing raw herbal material of better uniform quality. 相似文献
77.
Braga Lorrana Thas Mximo Durville Giraldo Alejandro Godinho Alexandre Lima 《Hydrobiologia》2022,849(2):309-321
Hydrobiologia - Mortality of fish entering the turbine draft tube (DT) from the tailrace is common during turbine startup or dewatering in Brazilian hydropower dams. Mortality can be reduced if... 相似文献
78.
Renan de Souza Rezende Gustavo Figueiredo Marques Leite Anderson Kennedy Soares De‐Lima Luis Antonio Braga Da Silva Filho Camila Vilarinho Costa Chaves Ana Cecilia Holler Prette June Spriger Freitas José Francisco Gonçalves Júnior 《Austral ecology》2015,40(6):693-700
The allochthonous detritus that accumulates in the substrate of streams is used by aquatic invertebrate shredders for shelter and food. Shredders are considered rare in tropical systems, and little information is available about the role of density effects and predation risk (associated with the perception of predators by prey) in relationship to the resources used by these organisms. The aim of this study was to examine experimentally the effects of increased predation risk and of the density of Phylloicus sp. (i.e. of two types of biological relationships) on the processing of the leaf litter of Nectandra megapotamica (Spreng.) Mez. Phylloicus sp. can use leaf litter for case building and as a food resource. The density effect was measured using four treatments that differed only in the number of individuals (one, two, three or four). A second experiment with five treatments was performed to test the risk of non‐lethal predation on detritus consumption (shelter and food) by Phylloicus sp. (T1: Caddisfly; T2: Mayfly; T3: Astyanax sp./fish; T4: Damselflies; T5: Stonefly). A single Phylloicus and one other organism (a potential predator blocked with 0.5 mm fine mesh) were placed in each tank (0.002 m3 volume). We observed a negative effect of density on per capita litter consumption (experiment 1). The low density of Phylloicus may be a natural factor that decreases intraspecific competition. In the presence of fish, Phylloicus showed the lowest amount of litter processing observed in the experiment, indicating top‐down control (experiment 2). In treatments that involved the presence of invertebrates (non‐predatory and predatory), Phylloicus showed the highest amount and an intermediate amount of leaf litter processing, respectively (experiment 2). This observation also suggests that the predation effect is more probable for specific predator–prey pairs. Population density and predation risk in Phylloicus may be important factors controlling leaf litter processing. 相似文献
79.
Many approaches to compute the genomic distance are still limited to genomes with the same content, without duplicated markers. However, differences in the gene content are frequently observed and can reflect important evolutionary aspects. While duplicated markers can hardly be handled by exact models, when duplicated markers are not allowed, a few polynomial time algorithms that include genome rearrangements, insertions and deletions were already proposed. In an attempt to improve these results, in the present work we give the first linear time algorithm to compute the distance between two multichromosomal genomes with unequal content, but without duplicated markers, considering insertions, deletions and double cut and join (DCJ) operations. We derive from this approach algorithms to sort one genome into another one also using DCJ operations, insertions and deletions. The optimal sorting scenarios can have different compositions and we compare two types of sorting scenarios: one that maximizes and one that minimizes the number of DCJ operations with respect to the number of insertions and deletions. We also show that, although the triangle inequality can be disrupted in the proposed genomic distance, it is possible to correct this problem adopting a surcharge on the number of non-common markers. We use our method to analyze six species of Rickettsia, a group of obligate intracellular parasites, and identify preliminary evidence of clusters of deletions. 相似文献
80.
Workers dominate male production in the neotropical bumblebee Bombus wilmattae (Hymenoptera: Apidae)