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排序方式: 共有264条查询结果,搜索用时 256 毫秒
81.
Jonathan L. Huska Luis Gaitero Brigitte A. Brisson Stephanie Nykamp Jeff Thomason William C. Sears 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(10):975-980
Presence of residual material following mini-hemilaminectomy in dogs (n = 9) with spontaneous thoracolumbar intervertebral disc extrusion was prospectively investigated. Volume of extruded disc material within the vertebral canal and the proportion of residual material were determined using pre- and post-operative magnetic resonance imaging. The degree of spinal cord compression, proportion of extradural material considered hemorrhage, and invasion of the articular facets were also determined. Residual material was identified in 44% of the mini-hemilaminectomies. The median percentage of residual material calculated was 7.7% of the preoperative volume. No observed effect of surgical side or site, proportion of extradural material considered hemorrhage, patient weight, and duration of clinical signs was detected. 相似文献
82.
Endogenous opioid binding to micro receptors is hypothesized to mediate natural rewards and has been proposed to be the basis of infant attachment behavior. Here, we report that micro-opioid receptor knockout mouse pups emit fewer ultrasonic vocalizations when removed from their mothers but not when exposed to cold or male mice odors. Moreover these knockout pups do not show a preference toward their mothers' cues and do not show ultrasonic calls potentiation after brief maternal exposure. Results from this study may indicate a molecular mechanism for diseases characterized by deficits in attachment behavior, such as autism or reactive attachment disorder. 相似文献
83.
Coseismic and Postseismic Fault Slip for the 17 August 1999, M = 7.5, Izmit, Turkey Earthquake 总被引:2,自引:0,他引:2
Reilinger RE Ergintav S Bürgmann R McClusky S Lenk O Barka A Gurkan O Hearn L Feigl KL Cakmak R Aktug B Ozener H Töksoz MN 《Science (New York, N.Y.)》2000,289(5484):1519-1524
We use Global Positioning System (GPS) observations and elastic half-space models to estimate the distribution of coseismic and postseismic slip along the Izmit earthquake rupture. Our results indicate that large coseismic slip (reaching 5.7 meters) is confined to the upper 10 kilometers of the crust, correlates with structurally distinct fault segments, and is relatively low near the hypocenter. Continued surface deformation during the first 75 days after the earthquake indicates an aseismic fault slip of as much as 0.43 meters on and below the coseismic rupture. These observations are consistent with a transition from unstable (episodic large earthquakes) to stable (fault creep) sliding at the base of the seismogenic zone. 相似文献
84.
Beaugrand J Crônier D Thiebeau P Schreiber L Debeire P Chabbert B 《Journal of agricultural and food chemistry》2004,52(23):7108-7117
The external layers of wheat grain were investigated during maturation with respect to chemical and structural features and xylanase degradability. Cytochemical changes were observed in the isolated peripheral tissues of the wheat grain at four defined stages following anthesis. Marked chemical changes were highlighted at 11 days after anthesis, for which protein and lipid contents varied weakly. The profile of esterified ferulic acid showed large variation in the maturing peripheral layers of grain in contrast to the deposition of ferulate dimers, p-coumaric and sinapic acids. Lignin was monitored at the latest stages of ripening, which corresponds to the cessation of reserve accumulation in the grain. Arabinoxylans (AX) reached a maximum at 20 days and did not display any significant change in arabinosyl substitution proportion until ripeness. When submitted to xylanase, all outer layers were similarly altered in the proportion of soluble AX except for the peripheral tissues of the 11-day-aged wheat grain that had very little AX. Aleurone and nucellar layers were mostly degraded, whereas pericarp stayed intact at all stages of maturation. This degradation pattern was connected with the preferential immunolocalization of xylanase in aleurone and nucellar layers irrespective of the developmental stages. Further chemical examination of the enzyme-digested peripheral tissues of the grain supports the facts that ferulic ester is not a limiting factor in enzyme efficiency. Arabinose branching, ferulic dimers, and ether-linked monomers that are deposited early in the external layers would have more relevance to the in situ degradability of AX. 相似文献
85.
Hélène Laparra Monique Burrus Reiner Hunold Brigitte Damm Ana Maria Bravo-Angel Roberte Bronner Günther Hahne 《Euphytica》1955,85(1-3):63-74
Summary Suitable sunflower tissues and cells were transformed either by direct gene transfer into protoplasts, particle bombardment, or Agrobacterium co-culture. While all techniques allowed efficient short-term or transient expression of the introduced gene(s) in the respective tissues, stable transformation was only observed after transformation with Agrobacterium. The latter technique was suitable for the production of transgenic callus from seedling cotyledons and occasional shoots with chimaeric expression of the transgene. Detailed analysis of the interaction of Agrobacterium with this explant showed that infection efficiency was critically dependent on the co-culture conditions, and that the preferentially-transformed cells were not the ones competent for regeneration.Abbreviations BAP
benzyl adenine
- CAT
chloramphenicol acetyl transferase
- 2,4-D
2,4-dichloro phenoxy acetic acid
- GUS-
D-glucuronidase
- MS
medium according to Murashige & Skoog (1962)
- NAA
naphthalene acetic acid
- NPTII
neomycin phospho transferase II
- PEG
polyethylene glycol
- PIG
particle inflow gun
- SH
medium according to Schenk & Hildebrandt (1972) 相似文献
86.
Geert J. W. Janssen Arend van Norel Brigitte Verkerk-Bakker Richard Janssen 《Euphytica》1995,92(3):287-294
Summary Over 5000 plants from 64 tuber-bearing wild Solanum spp. have been individually screened for resistance to Meloidogyne chitwoodi, M. fallax and M. hapla. Seedlings were analyzed by means of counting number of egg masses and resistance was verified by retesting low-scoring plants using stem cuttings. Resistance to both M. chitwoodi and M. fallax was observed in S. bulbocastanum, S. cardiophyllum, S. brachistotrichum, S. fendleri and S. hougasii. Only in S. chacoense and to a lesser extent in S. stoloniferum and S. gourlayi differential results between M. chitwoodi and M. fallax were observed. Resistance to M. hapla was found in S. bulbocastanum, S. brachistotrichum, S. cardiophyllum, S. arnezii, S. chacoense, S. tarijense, S. boliviense, S. gourlayi, S. microdontum, S. sparsipilum, S. spegazzinii, S. sucrense, S. acaule and S. hougasii. The occurrence of resistance in wild Solanum species in relation to their taxonomic status and the implications for introgression of resistance into S. tuberosum are discussed. 相似文献
87.
88.
Barbara Thuerig Ana Slaughter Elaheh Marouf Matthias Held Brigitte Mauch-Mani Lucius Tamm 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(2):255-265
The influence of site on resistance of grapevine (cv. Chasselas) to Plasmopara viticola was evaluated. Grapevine leaves from three vineyards in the region of Lake Neuchatel (Switzerland) were tested for their
susceptibility to P. viticola in the lab in five successive years (2004–2008), and the expression levels of four selected defence-related genes (Glucanase, Lipoxygenase 9, 9-cis epoxycarotenoid dioxygenase, Stilbene synthase) were studied in 1 year. In all 5 years of examination, differences between sites were substantial. In four out of 5 years,
plants from site Hauvernier were much less susceptible to P. viticola than plants from site Auvernier. In another year, differences were less pronounced but still significant for one leaf age.
Susceptibility of plants from a third site (Concise) varied from year to year. Differences in the genetic background were
excluded by microsatellite analysis. Differences in susceptibility were mirrored in the constitutive expression pattern of
four defence-related genes, with samples from the Hauterive site clearly separated from samples of the other two sites in
redundancy analysis. Furthermore, it was evaluated whether site-specific resistance can be modulated by agronomic practices
such as the application of organic amendments. In two commercial vineyards (cv. Pinot noir), soils had either not (control) or yearly (compost) been amended with a compost for the last 9 years. Leaves
from plants grown in any of the two treatments did not differ in their susceptibility to P. viticola in both years of examination. Additionally, under controlled conditions, none of 19 different composts amended to the substrate
of grapevine seedlings or cuttings affected their susceptibility to P. viticola, but 8 out of 19 composts reduced severity in the control bioassay Arabidopsis thaliana—Hyaloperonospora arabidopsidis, indicating that a modulation of site-specific susceptibility of grapevine plants by organic amendments is at the very least,
difficult. 相似文献
89.
90.
Brigitte L.?MaassEmail author Ramni H.?Jamnadass Jean?Hanson Bruce C.?Pengelly 《Genetic Resources and Crop Evolution》2005,52(6):683-695
To improve understanding of diversity of Lablab purpureus and establish relationships among 103 germplasm accessions collected from diverse geographic origins, amplified fragment
length polymorphism markers were used. Four primer sets selected out of 16 produced 289 clear, repeatable polymorphisms. UPGMA
analysis of similarity data clustered the accessions according to their subspecific taxonomic organization, i.e., subsp. purpureus and subsp. uncinatus, as well as to cultivated and wild forms. The well-represented landraces from Africa and Asia, belonging predominantly to
subsp. purpureus, displayed moderate genetic diversity. Wild forms from Africa showed far greater levels of diversity that would justify taxonomic
re-assessment of the wild subsp. uncinatus. The molecular analysis identified forms that were collected in the wild in India but were genetically placed intermediate
between wild and cultivated forms. As these plant types did not exist among the African accessions, it is suggested that they
might represent escapes from early attempts of domestication. These results support the suggested pathway of domestication
and distribution of L. purpureus from Africa to Asia. Additional members to a previously published core collection of the species are proposed. 相似文献