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771.
目的:制备链亲合素标记的鼠白细胞介素21融合蛋白(mIL21-SA),治疗小鼠表浅膀胱癌。方法:构建mIL21-SA-pET21质粒,BL21表达,Ni-NTA纯化,透析复性,Western blot鉴定,MTT法检测其对小鼠胸腺细胞的增殖作用,流式检测其对生物素化的MB49锚定修饰率。建立小鼠MB49表浅膀胱癌模型,将mIL21-SA锚定在小鼠膀胱表面进行治疗并观察小鼠存活时间。60d后对mIL21-SA治疗后存活小鼠进行二次攻击。结果:mIL21-SA可以促进T细胞增殖,且具有SA介导的高效结合已生物素化的MB49表面的功能(修饰率98.74%)。膀胱灌注60d后,mIL21-SA组有10只(10/25)存活,二次攻击后,仍有6只(6/10)存活。与对照组比较均有统计学意义(P<0.05)。结论:该实验研制了具有双重活性的mIL21-SA,mIL21-SA锚定修饰治疗表浅膀胱癌是一种有效的免疫治疗方法。 相似文献
772.
Some moths species are considered good indicators of habitat quality because they are very responsive to human disturbance, vegetation type, and successional processes. However, Saturniidae moths have not yet been considered as indicators of environmental quality. Little is known on the distribution of moth species in different vegetation types and the moths’ seasonal variations in the Brazilian savannah. Therefore, this study aims to describe the spatial distribution and temporal patterns of moths belonging to the Saturniidae family in two vegetation types—Cerrado sensu stricto on rocky outcrops and semi-deciduous forest—in both the rainy and dry seasons. It addresses the influence of the climatic seasons and vegetation types on abundance, richness, and species composition to describe the temporal and spatial distribution patterns and the relationship between the ecological aspects and the life history of these moths. This study was conducted in the Cerrado phytogeographical domain, in Pireneus State Park, Goiás, Brazil. The results revealed that most Saturniidae species sampled are present during the rainy season and typically found in forest habitats. Furthermore, a clear positive connection was found between the abundance pattern and rainfall seasonality and humid habitats; this is apparently related to the physiological tolerance of these moths, due to rudimentary mouthparts during their adulthood. Thus, rainfall and a forest habitat are important to and fundamental requirements for the persistence of the Saturniidae species in the Cerrado domain. Based on the results of this study, we suggest the use of saturniid species as indicators of changes in vegetation and climatic conditions. 相似文献
773.
Vanesca Korasaki Rodrigo F. Braga Ronald Zanetti Fatima M. S. Moreira Fernando Z. Vaz-de-Mello Julio Louzada 《Biodiversity and Conservation》2013,22(6-7):1485-1499
Land-use systems (LUS), placed in originally forested areas, represent different degrees of opportunity for species conservation. In this study, we examined the dung beetle communities in order to identify the conservation value of different LUS: primary forest, old secondary forest, young secondary forest, agroforestry, agriculture and pasture in Western Amazon. The LUS were sampled in two campaigns during the highest precipitation period and dryest period. The primary forest has a high number of total and exclusive species. Large beetles show a continuous decreasing in richness and abundance from primary forest to pastures, while small ones are not sensible to intermediate systems (secondary forest to agriculture) in terms of species richness and exhibit a increase in abundance at agroforest and agriculture when contrasted to secondary forest and pasture The beetle community composition was not sensible to secondary forest recovering time. Secondary forests and agroforestry stood out as harboring many species shared with primary forests. Cloud-point dispersion (average dissimilarity) increased from primary forest towards LUS’s submitted to more intense use. The higher sampling points similarity observed in primary forest might be the result of the relative stability of this system, given that environmental impacts might increase variability in community structure and beta diversity. Increase in beta diversity as expressed by greater dispersion of sites in multivariate space suggests that these areas are dependent on nearby species pools, possibly primary forests, and harbor a higher spatial heterogeneity in species composition. This high variability can overestimate the importance of occasional species, thus biasing the actual value of alternative LUS for biodiversity conservation. 相似文献
774.
Ocean acidification by atmospheric carbon dioxide has increased almost continuously since the last glacial maximum (LGM), 21 000 years ago. It is expected to impair tropical reef development, but effects on reefs at the present day and in the recent past have proved difficult to evaluate. We present evidence that acidification has already significantly reduced the formation of calcified bacterial crusts in tropical reefs. Unlike major reef builders such as coralline algae and corals that more closely control their calcification, bacterial calcification is very sensitive to ambient changes in carbonate chemistry. Bacterial crusts in reef cavities have declined in thickness over the past 14 000 years with largest reduction occurring 12 000–10 000 years ago. We interpret this as an early effect of deglacial ocean acidification on reef calcification and infer that similar crusts were likely to have been thicker when seawater carbonate saturation was increased during earlier glacial intervals, and thinner during interglacials. These changes in crust thickness could have substantially affected reef development over glacial cycles, as rigid crusts significantly strengthen framework and their reduction would have increased the susceptibility of reefs to biological and physical erosion. Bacterial crust decline reveals previously unrecognized millennial‐scale acidification effects on tropical reefs. This directs attention to the role of crusts in reef formation and the ability of bioinduced calcification to reflect changes in seawater chemistry. It also provides a long‐term context for assessing anticipated anthropogenic effects. 相似文献
775.
The duration of the life cycle of Rhodnius robustus Larrousse, 1927 as well as the mortality rate of each nymphal instar were studied comparing groups fed on pigeon or on mouse blood weekly or fortnightly. This species showed a better development and lower mortality rate when fed on swiss mouse. The intervals between feedings apparently did not have influence on the shortening of the cycle. We suggest that laboratory colonies and experiments with R. robustus are better maintained when these triatomines are fed on swiss mouse. 相似文献
776.
dos Santos Braga Ramilla Pinto Rafael Barbosa Chaves Lázaro José Diniz-Filho José Alexandre Felizola Soares Thannya Nascimento Collevatti Rosane Garcia Pires de Campos Telles Mariana 《Tree Genetics & Genomes》2019,15(6):1-15
Tree Genetics & Genomes - Tree breeders must almost always address multiple traits. That entails choosing selection methods and weighing up known or assumed economic-worth functions for traits.... 相似文献
777.
778.
779.
Coralline algal nodules off Fraser Island, eastern Australia 总被引:1,自引:0,他引:1
Summary Calcareous red algal nodules growing on mobile substrates have been sampled from 28 to 117m off Fraser Island in southern
Queensland, eastern Australia. This is a subtropical, transitional area between the tropical Great Barrier Reef to the north
and temperate, cooler waters to the south. Red algal nodules are the most common components in bioclastic gravels that extend
from about 50 to 110 m and locally cover 40–50% of the seafloor. Variations in the overall character and floristic composition
of the nodules with depth can be observed. Algal nodules comprise algal covered pebbles/cobbles and rhodoliths in depths shallower
than 60 m whereas only rhodoliths occur in deeper settings. No changes in nodule shape occur but shallower algal nodules have
larger mean size with higher standard deviation than the deeper ones (39.2 vs. 30.5 mm and 20.5 vs. 6.3 mm s.d.). Living and
subrecent red algae in nodules shallower than 60 m are mainly Melobesioideae and peyssonneliaceans with minor Lithophylloideae
and Mastophoroideae. Most plants belong to a few species of the generaPhymatolithon andLithothamnion. Below 68 m, rhodoliths are dominated by the family Sporolithaceae, melobesioids and peyssonneliaceans.Sporolithon is the main component below 80 m. Algal growth forms are mostly smooth encrusting to warty with no depth variation. Maximum
plant thickness, however, decreases with increasing depth. Thallus thickness in the deeper water samples is more than three
times smaller than in those from shallower waters. These data are important for understanding the paleoenvironmental context
of deposition of the abundant coralline algal limestones with similar algal nodules found in the geological record. 相似文献
780.
Roberta Gomes Carvalho Ricardo Louren?o-de-Oliveira Ima Aparecida Braga 《Memórias do Instituto Oswaldo Cruz》2014,109(6):787-796
The geographical distribution of Aedes albopictus in Brazil was updated according to
the data recorded across the country over the last eight years. Countrywide house
indexes (HI) for Ae. albopictus in urban and suburban areas were described for the
first time using a sample of Brazilian municipalities. This mosquito is currently
present in at least 59% of the Brazilian municipalities and in 24 of the 27 federal
units (i.e., 26 states and the Federal District). In 34 Brazilian municipalities, the
HI values for Ae. albopictus were higher than those recorded for Ae. aegypti,
reaching figures as high as HI = 7.72 in the Southeast Region. Remarks regarding the
current range of this mosquito species in the Americas are also presented. Nineteen
American countries are currently infested and few mainland American countries have
not confirmed the occurrence of Ae. albopictus. The large distribution and high
frequency of Ae. albopictus in the Americas may become a critical factor in the
spread of arboviruses like chikungunya in the new world. 相似文献