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排序方式: 共有308条查询结果,搜索用时 375 毫秒
81.
Flávio de Oliveira Silva Priscila das Neves Santos Evellyne de Oliveira Figueirôa Cristiane Moutinho Lagos de Melo Juliana Kelle de Andrade Lemoine Neves Francisco Vassiliepe Sousa Arruda João Batista Cajazeiras Kyria Santiago do Nascimento Edson Holanda Teixeira Benildo Sousa Cavada Ana Lúcia Figueiredo Porto Valéria Rêgo Alves Pereira 《Research in veterinary science》2014
Lectins are proteins or glycoproteins with the ability to link to carbohydrates at the cell surface in a specific and reversible manner. Studies have showed that lectins are demonstrate immunomodulatory and antitumor agents. This study aims to evaluate the effect of lectin extracted from the seeds of Canavalia brasiliensis (ConBr) on murine melanoma B16F10 cells by analyzing cell viability, apoptosis index, cell migration, production of cytokines and nitric oxide (NO). Results showed that ConBr was able to reduce cell viability and thwart apoptosis, which could be observed by decrease in cell migration. ConBr also induced NO and IL-12 synthesis. Altogether, these data demonstrate the potential of ConBr as a therapeutic agent for melanoma. 相似文献
82.
Cichowski K Shih TS Schmitt E Santiago S Reilly K McLaughlin ME Bronson RT Jacks T 《Science (New York, N.Y.)》1999,286(5447):2172-2176
Neurofibromatosis type 1 (NF1) is a prevalent familial cancer syndrome resulting from germ line mutations in the NF1 tumor suppressor gene. Hallmark features of the disease are the development of benign peripheral nerve sheath tumors (neurofibromas), which can progress to malignancy. Unlike humans, mice that are heterozygous for a mutation in Nf1 do not develop neurofibromas. However, as described here, chimeric mice composed in part of Nf1-/- cells do, which demonstrates that loss of the wild-type Nf1 allele is rate-limiting in tumor formation. In addition, mice that carry linked germ line mutations in Nf1 and p53 develop malignant peripheral nerve sheath tumors (MPNSTs), which supports a cooperative and causal role for p53 mutations in MPNST development. These two mouse models provide the means to address fundamental aspects of disease development and to test therapeutic strategies. 相似文献
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85.
Maria Pilar Serrano‐Muela Estela Nadal‐Romero Noemí Lana‐Renault Jos Carlos Gonzlez‐Hidalgo Juan Ignacio Lpez‐Moreno Santiago Beguería Yasmina Sanjuan Jos María García‐Ruiz 《Land Degradation \u0026amp; Development》2015,26(3):249-262
An exceptional rainfall and hydrological event occurred on 19–21 October 2012 in the central western Pyrenees and was particularly significant in the Upper Aragón River basin and its tributaries, mainly the Irati River. Analysis of historical records showed that, considered separately, the event of 19 and 20 October ranked between the second and fifth highest most extreme daily precipitation events. For the two days combined (with a total between 200 and 260 mm), the precipitation event was the most extreme 2‐day event among all observation stations but one. The consequent flood destroyed part of an urban area, and a long stretch of a national road triggered landslides, enlarged the alluvial plain and caused generalised soil erosion in cultivated fields cropped with winter cereals. Badlands in the marls of the Inner Depression yielded high volumes of sediment. The floods in the tributaries were relatively moderate (return periods of 14–42 years), whereas in the Upper Aragón River, the flood corresponded to a return period of approximately 400–500 years and to 142 years at the end of the Yesa reservoir, although difficulties in estimating the discharge increased the uncertainty of these values. The Yesa and Itoiz reservoirs considerably reduced the intensity of the flood in the middle and lower Aragón River and confirmed the importance of the water level in the reservoirs when such rainfall events occur. The water storage in the Yesa reservoir increased from 16% to 53% as a consequence of the event. More integrated studies are necessary to decrease the risks associated with flood hazards. This is particularly the case in mountain areas, where the steep slopes and longitudinal gradients of the rivers shorten the concentration time of floods and increase the energy that erodes channels and riverbanks. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
86.
Carlos A. Cairo Juliana Stein Luciana Delgado Santiago Bortolotti Sebastián A. Guelman Juan Pablo A. Ortiz Eligio N. Morandi 《Euphytica》2002,124(3):387-395
Soybean cultivars carrying the `long juvenile trait' show a delayed flowering response under short day conditions. The incorporation
of this character into genotypes of agronomic interest may allow a broader range of sowing dates and latitudes for a single
cultivar adaptation. The objective of this work was to identify molecular markers linked to the juvenile locus in soybean.
Experiments were carried out using two pairs of near isogenic lines(NILs) differing in the presence of the long juvenile trait,
and RAPD markers. Four hundred primers were first screened to find polymorphism associated with the trait. Additional differences
between NILs were sought by digesting the genomic DNA with five restriction enzymes. Polymorphic fragments detected between
NILs were tested for linkage to the juvenile locus in the corresponding F2 segregating populations. Marker bc357-HaeIII was linked (χ2L = 46.316) to the juvenile locus with an estimated recombination frequency of 0.13 ± 0.03in one of the genetic backgrounds
studied. The fragment was cloned, sequenced and converted into a SCAR marker. Moreover,bc357-HaeIII was used as RFLP probe. Both, SCAR and RFLP generated markers linked to the juvenile locus in the two genetic backgrounds
analysed. Results presented in this work can be utilised for both, the localisation of the gene associated with the character
and for tagging the juvenile trait in soybean breeding programs.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
87.
Summary The maturity rating of maize (Zea mays L.) grown in Galicia (Northwestern Spain) varies from FAO 200 to 600. Later germplasm has usually too much moisture content in the kernel at normal harvesting time so serious problems with storing could appear. Besides, farmers have tended to use earlier varieties in the last few years. All this imposes limitations on the amount of germplasm available to develop varieties adapted to this area.To study the possibility of adapting late, exotic material to the environment of the Atlantic coast of Galicia we carried out six cycles of individual selection on two non-adapted populations of maize (Purdue A and Purdue B). The criterion of selection was early silking and the criterion of response was moisture content of kernel at harvesting.The original populations and the populations obtained after each cycle of selection were crossed to the hybrids CM105 × CM109 (tester Reid) and H99 × H95 (tester Lancaster) and were evaluated in four environments to study the efficiency of the selection scheme. There were significant reductions in days to silking (6.1 and 6.7 days from cycle 0 to cycle 6 for Purdue A and Purdue B, respectively) and grain moisture at harvesting (3.0 and 3.9% from cycle 0 to cycle 6 for Purdue A and Purdue B, respectively). There were also reductions in plant height and yield in both populations.In general, the crosses population × Lancaster were higher for yield than the crosses population × Reid. Yield of the population crosses by both testers decreased after the six cycles of selection probably because of the earlier maturity of the selected populations. Some inbreeding depression may also have occurred. 相似文献
88.
Pedro Vital Brasil Ramos Fabyano Fonseca e Silva Luiz Otávio Campos da Silva Gustavo Garcia Santiago Gilberto Romeiro de Oliveira Menezes José Marcelo Soriano Viana Roberto A. A. Torres Júnior Andrea Gondo Luiz F. Brito 《Reproduction in domestic animals》2020,55(3):266-273
Cow stayability plays a major role on the overall profitability of the beef cattle industry, as it is directly related to reproductive efficiency and cow's longevity. Stayability (STAY63) is usually defined as the ability of the cow to calve at least three times until 76 months of age. This is a late-measured and lowly heritable trait, which consequently constrains genetic progress per time unit. Thus, the use of genomic information associated with novel stayability traits measured earlier in life will likely result in higher prediction accuracy and faster genetic progress for cow longevity. In this study, we aimed to compare pedigree-based and single-step GBLUP (ssGBLUP) methods as well as to estimate genetic correlations between the proposed stayability traits: STAY42, STAY53 and STAY64, which are measured at 52, 64 and 76 months of cow's age, considering at least 2, 3 and 4 calving, respectively. ssGBLUP yielded the highest prediction accuracy for all traits. The heritability estimates for STAY42, STAY53, STAY63 and STAY64 were 0.090, 0.151, 0.152 and 0.143, respectively. The genetic correlations between traits ranged from 0.899 (STAY42 and STAY53) to 0.985 (STAY53 and STAY63). The high genetic correlation between STAY42 and STAY53 suggests that besides being related to cow longevity, STAY53 is also associated with the early-stage reproductive efficiency. Thus, STAY53 is recommended as a suitable selection criterion for reproductive efficiency due to its higher heritability, favourable genetic correlation with other traits, and measured earlier in life, compared with the conventional stayability trait, that is STAY63. 相似文献
89.
L.M.B. Garcia C.M.H. Garcia A.F.S. Pineda E.A. Gammad J. Canta S.P.D. Simon G.V. Hilomen-Garcia A.C. Gonzal C.B. Santiago 《Aquaculture International》1999,7(4):241-250
Bighead carp (Aristichthys nobilis Oshima) fry of various ages (11, 18, and 35 days post-hatch) were exposed to the low salinities encountered during the annual intrusion of seawater in Laguna Lake, Philippines. Practical indices of salinity tolerance assessed the effect of a 96 h direct exposure to low salinities (0–16). Mean (MST) and median survival times (MST50) of fry decreased as salinity of rearing medium increased. Younger fry were less able to tolerate exposure to these salinities than their older cohorts. Median lethal salinity after 96 h (MLS) revealed higher tolerance among 35–day old fry (7.6) than 11 (2.3) and 18–day old fry (6.0), demonstrating that survival in saline water depends on their age at initial exposure to low salinities. Mean body weight of 18–day old fry reared in 0 and 2 for 3 and 4 weeks was higher than for those reared in 4 and 6 for the same period. Growth over these periods was inversely related with the range of salinities tested. These results demonstrate that, despite their known stenohalinity, bighead carp fry possess some degree of osmoregulatory capability, allowing them to survive and grow in lakes subjected periodically to saltwater inflow. 相似文献
90.
Comparison of relascope and fixed-radius plots for the estimation of forest stand variables in northeast Spain: an inventory simulation approach 总被引:1,自引:0,他引:1
Míriam Piqué Berta Obon Sonia Condés Santiago Saura 《European Journal of Forest Research》2011,130(5):851-859
The Bitterlich relascope is a multiple use dendrometer widely used in forest inventory. Although it is most commonly used
to estimate basal area, the relascope can also estimate other stand variables, including density and diameter distribution.
However, forest stand inventories in Spain rarely use relascope plots to estimate these variables due to the belief that they
lead to higher errors than fixed-radius plots due to the heterogeneity of many Mediterranean forests. This study compared
the accuracy of the estimated averages of three main stand variables (basal area, stand density, and diameter class distribution)
in forest stand inventories performed with relascope plots and with conventional fixed-radius circular plots, both measuring
a similar number of trees (15–20). A forest stand inventory simulator (DOMO) was used (1) to generate simulated forest stands
corresponding to the nine most common types in the Mediterranean region of Catalonia (NE Spain), including even-aged and uneven-aged
stands, and (2) to estimate and compare the average values of these variables at the forest stand level resulting from both
plot types. In general, we did not find significant accuracy differences between the inventory systems for most of the stand
variables and forest types studied, as expected by established angle-count sampling theory. However, the results show that
for stands with multiple strata and open structures, the Bitterlich relascope provides a more accurate estimate for basal
area than for density, while the reverse occurs for fixed-radius plots. 相似文献