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91.
Filipa Cox Nadia Barsoum Martin I. Bidartondo Isabella Børja Erik Lilleskov Lars O. Nilsson Pasi Rautio Kath Tubby Lars Vesterdal 《Annals of Forest Science》2010,67(2):200-200
The functionally critical role of mycorrhizal fungi in forest ecosystems, and the imminent threat of climate change that may
act to alter mycorrhizal functional biodiversity, means there is an urgent need for a regional to continental-scale assessment
of mycorrhizal distributions. Until recently, it had not been possible to cost-effectively assess mycorrhizas precisely and
accurately. A large-scale survey of ICP Forests plots would be only the first stage in answering many of the questions outlined
above, but it is essential if future studies are going to address these questions with hypothesis-driven research in a cohesive
manner, rather than remain independent for lack of a unified approach. The chance to utilise the vast network of biomonitoring
plots at this time is a remarkable opportunity because it minimises the logistics and costs associated with achieving such
an enormous effort and provides a rare stable — past and future — ground for forest ecosystem scientific investigation. In
the face of rapid global change, we finally have an opportunity to accurately integrate mycorrhizal distribution data with
long-term environmental monitoring, providing a basic understanding of functionally crucial organisms, and at the same time
creating an invaluable resource for future research. 相似文献
92.
Pin PA Benlloch R Bonnet D Wremerth-Weich E Kraft T Gielen JJ Nilsson O 《Science (New York, N.Y.)》2010,330(6009):1397-1400
Cultivated beets (Beta vulgaris ssp. vulgaris) are unable to form reproductive shoots during the first year of their life cycle. Flowering only occurs if plants get vernalized, that is, pass through the winter, and are subsequently exposed to an increasing day length (photoperiod) in spring. Here, we show that the regulation of flowering time in beets is controlled by the interplay of two paralogs of the FLOWERING LOCUS T (FT) gene in Arabidopsis that have evolved antagonistic functions. BvFT2 is functionally conserved with FT and essential for flowering. In contrast, BvFT1 represses flowering and its down-regulation is crucial for the vernalization response in beets. These data suggest that the beet has evolved a different strategy relative to Arabidopsis and cereals to regulate vernalization. 相似文献
93.
94.
Harry Nilsson 《Potato Research》1960,3(1):1-12
Ohne Zusammenfassung
Vortrag gehalten für „The 4th International Informal Potato Conference” at Lund, August 1957. 相似文献
95.
Comparison of histology and clinical variables to DNA ploidy in canine mammary tumors 总被引:2,自引:0,他引:2
Flow cytometric DNA analysis was done on 132 canine mammary tumors from 99 dogs to evaluate the relation to histology and to clinical staging. Seventy-one tumors (54%) were histologically malignant; 38 (54%) of these were aneuploid and 33 (46%) were diploid. Fifty-two (39%) tumors were histologically benign, of which 45 (87%) were diploid and seven (13%) aneuploid. There were nine dysplastic mammae (7%); two were aneuploid and the rest diploid. DNA indices varied from 0.72 to 2.35. Of 58 mammary carcinomas, 25 (43%) were diploid and 33 (57%) were aneuploid (of the latter, 16 showed hypodiploidy and 17 hyperdiploidy with a predominance between DNA index 1.10 and 1.50). Three tumors (two carcinomas and one malignant mixed tumor) were multiploid with two aneuploid cell populations. The histological type varied within eight tumors, and in four of these the DNA index also varied. DNA indices varied within three tumors with uniform morphology. No correlation was found between DNA index and age of the dogs, nor between DNA index and tumor size. No significant differences were found between DNA index and histology, tumor growth pattern, or tumor location. Benign tumors were smaller than carcinomas, which were smaller than malignant mesenchymal tumors. Tumors growing adherent to the skin were larger than those not adherent to the skin. The regional lymph nodes were examined in 33 cases. No significant difference between the mean DNA index and presence of lymph node metastasis was found. These results show the possibility of using flow cytometry for DNA analysis in canine mammary tumors.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
96.
Feline insular amyloid: immunohistochemical and immunochemical evidence that the amyloid is insulin-related 总被引:3,自引:0,他引:3
K H Johnson P Westermark G Nilsson K Sletten T D O'Brien D W Hayden 《Veterinary pathology》1985,22(5):463-468
Utilizing islet amyloid-laden pancreatic tissues from six diabetic cats, we demonstrated substantial immunoreactivity (peroxidase-antiperoxidase technique) of the islet amyloid with antiserum to a B chain-rich insulin fraction, but no reactivity with antisera to insulin, glucagon, or somatostatin. Islet amyloid was purified from two cats and a protein unique to the diabetic and islet amyloid-laden cats was separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Immunoreactivity of this protein with antiserum to the B chain-rich insulin fraction was also shown by immunoblotting. Attempts to obtain the amino acid composition of the purified unique protein (represented by a single 25,000 dalton band on gel electrophoresis) were not successful because the amount of protein was too small. These results provide important additional evidence that an insulin-related protein is involved in the formation of islet amyloid. Our study also shows that the diabetic cat provides several advantages for the continued study of the etiopathogenic relationship of islet amyloid and diabetes mellitus. 相似文献
97.
98.
Zoric M Sjölund M Persson M Nilsson E Lundeheim N Wallgren P 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2004,51(6):278-284
A group of 175 newborn piglets were monitored with respect to development of abrasions and lameness. Lameness was diagnosed in 10.9% of the piglets. About every second litter was affected and around 75% of these diagnoses took place during the first 3 weeks of life. Skin lesions were present already on day 3. They increased in magnitude until day 10 and thereafter declined. They were generally bilateral and most commonly observed as abrasions over the carpal joints. Hocks, face and tails were affected in a similar way, but at lower magnitudes. Sole bruising was observed in 87% of the piglets on the third day of life, and moderate to severe lesions dominated until day 10. Thereafter the incidence decreased, indicating healing with time. Still 39% of the piglets were affected at day 17. There was a significant positive correlation between skin lesions of carpus and hock within all examination days in selected piglets with known identity (n = 48). Between day 10 and 17 significant positive correlations were found within all examination sites with exception of abdomen and teats. The offspring of sows treated against mastitis expressed more abrasions then piglets delivered by healthy sows and the mortality during the first 17 days postpartum was significantly higher among piglets delivered by sows treated for mastitis. The level of serum antibodies to Streptococcus equisimilis in eight dams decreased during the last month of gestation and a declining maternal immunity to S. equisimilis was demonstrated in all piglets (n = 47) during the first 5 weeks of life. During the first 2 weeks of life somewhat lower median levels of serum antibodies were recorded among the piglets that were treated against arthritis (n = 8). 相似文献
99.
Martin Olofsson Teresa Lamela Emmelie Nilsson Jean-Pascal Bergé Victória del Pino Pauliina Uronen Catherine Legrand 《Marine drugs》2014,12(4):1891-1910
Instead of sole nutrient starvation to boost algal lipid production, we addressed nutrient limitation at two different seasons (autumn and spring) during outdoor cultivation in flat panel photobioreactors. Lipid accumulation, biomass and lipid productivity and changes in fatty acid composition of Nannochloropsis oculata were investigated under nitrogen (N) limitation (nitrate:phosphate N:P 5, N:P 2.5 molar ratio). N. oculata was able to maintain a high biomass productivity under N-limitation compared to N-sufficiency (N:P 20) at both seasons, which in spring resulted in nearly double lipid productivity under N-limited conditions (0.21 g L−1 day−1) compared to N-sufficiency (0.11 g L−1 day−1). Saturated and monounsaturated fatty acids increased from 76% to nearly 90% of total fatty acids in N-limited cultures. Higher biomass and lipid productivity in spring could, partly, be explained by higher irradiance, partly by greater harvesting rate (~30%). Our results indicate the potential for the production of algal high value products (i.e., polyunsaturated fatty acids) during both N-sufficiency and N-limitation. To meet the sustainability challenges of algal biomass production, we propose a dual-system process: Closed photobioreactors producing biomass for high value products and inoculum for larger raceway ponds recycling waste/exhaust streams to produce bulk chemicals for fuel, feed and industrial material. 相似文献
100.
E. M.
stman M. Nilsson H. G. M. Liljeberg Elmsthl G. Molin I. M. E. Bjrck 《Journal of Cereal Science》2002,36(3):339
It has been observed that bread containing lactic acid produced during the sourdough fermentation or added directly, has the ability to lower the postprandial glucose and insulin responses in humans. The main objective of the present work was to evaluate the possible mechanisms for a lowered glucose response to bread containing lactic acid, and to determine whether the same phenomenon also occurs when lactic acid is added to other cereal products. The rate of starch hydrolysis in bread and bread-like products was studied using an in vitro enzymatic approach. In addition, blood glucose and insulin responses to different lactic acid fermented barley gruels were evaluated in healthy subjects. It was concluded that the inclusion of lactic acid in bread reduces the rate of starch digestion by creating interactions between the gluten and starch. The presence of lactic acid during starch gelatinisation appeared to be a prerequisite for a reduced starch bioavailability. No effect of lactic acid was seen in gruels where the acid was formed after heat-treatment. 相似文献