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排序方式: 共有83条查询结果,搜索用时 343 毫秒
1.
Pekka Oja Raija M. T. Laukkanen T. Katriina Kukkonen-Harjula Ilkka M. Vuori Matti E. Pasanen Seppo P. T. Niittym?ki Tiina Solakivi 《European journal of applied physiology and occupational physiology》1991,62(6):400-404
Two experiments were carried out to compare the cardiorespiratory and metabolic effects of cross-country skiing and running training during two successive winters. Forty-year-old men were randomly assigned into skiing (n = 15 in study 1, n = 16 in study 2), running (n = 16 in study 1 and n = 16 in study 2) and control (n = 17 in study 1 and n = 16 in study 2) groups. Three subjects dropped out of the programme. The training lasted 9-10 weeks with 40-min exercise sessions three times each week. The training intensity was controlled at 75%-85% of the maximal oxygen consumption (VO2max) using portable heart rate metres and the mean heart rate was 156-157 beats.min-1 in the training groups. In the pooled data of the two studies the mean increase in the VO2max (in ml.min-1.kg-1) on a cycle ergometer was 17% for the skiing group, 13% for the running group and 2% for the control group. The increase in VO2max was highly significant in the combined exercise group compared to the control group but did not differ significantly between the skiing and running groups. The fasting serum concentrations of lipoproteins and insulin did not change significantly in any of the groups. These results suggested that training by cross-country skiing and running of the same duration and intensity at each session for 9-10 weeks improved equally the cardiorespiratory fitness of untrained middle-aged men. 相似文献
2.
A cDNA probe for the low density lipoprotein (LDL) receptor gene was used to screen DNA samples from 52 unrelated Finnish patients with the heterozygous form of familial hypercholesterolemia (FH) and 51 healthy controls. Southern blot analysis using the restriction enzyme PvuII revealed an abnormal 11 kb (kilo base-pair) restriction fragment in 16 (31%) of the patients but none of the controls. A more detailed restriction enzyme analysis of the DNA from patients revealed a mutation which apparently is due to an 8 kb deletion extending from intron 15 to exon 18 of the LDL receptor gene. Co-segregation of FH with the mutated gene was demonstrated in three families. These data are consistent with a ‘founder gene effect’ and support the assumption that recombinant DNA methods may have great impact on the diagnostics of FH in genetically homogeneous populations. 相似文献
3.
Predator-induced phenotypic plasticity in Daphnia pulex: uncoupling morphological defenses and life history shifts 总被引:1,自引:1,他引:0
Chemical cues from a predator Chaoborus sp. induce morphological defense (neck spine) and life history shifts (later reproduction, decreased fecundity but larger juvenile size) in the waterflea Daphnia pulex. These shifts have been interpreted either as costs of defense or as separate adaptation. In order to investigate if the life history shifts can be separated from the morphological defense, Daphnia pulex individuals were exposed to chemical cues from Chaoborus at different stages of life for variable periods. The daphnids that were exposed to Chaoborus started their reproduction later than the controls, although the differences were not statistically significant. Neck spine was induced only if daphnids were exposed to Chaoborus in an early stage of their life. Numbers of eggs produced were not affected by the different treatments, but egg mortality was higher in mothers exposed to Chaoborus. With these treatments it was possible to see neck spine induction without measurable life history changes or costs. On the other hand, irrespective of neck spine presence, the Chaoborus chemical(s) had an effect on Daphnia pulex mothers.Publication no 2159. Netherlands Institute of Ecology, Centre for LimnologyPublication no 2159. Netherlands Institute of Ecology, Centre for Limnology 相似文献
4.
Kristian Aspegren Leena Mannonen Anneli Ritala Riitta Puupponen-Pimiä Ulrika Kurtén Marjatta Salmenkallio-Marttila Veli Kauppinen Teemu H. Teeri 《Molecular breeding : new strategies in plant improvement》1995,1(1):91-99
Transgenic plant cell cultures have a potential for production and secretion of important proteins and peptides. To assess the possibilities of using a stable barley suspension culture for secretion of heterologous proteins in active form, we expressed the cDNA of the thermostable-glucanase (EGI) ofTrichoderma reesei in barley suspension cells. The cDNA coding for EGI and its signal sequence was placed under the control of the CaMV 35S promoter and the construction was transferred to the cells by particle bombardment. Stably transformed lines were obtained by selecting for a cotransformed antibiotic resistance marker. The expression of EGI cDNA led to accumulation of EGI in the culture medium, as shown by analysis with EGI-specific antibodies. Enzymatic assays confirmed that the EGI secreted by the suspension cells retained its activity and thermostable character. Furthermore, it was shown that the enzyme produced by the transgenic suspension culture could be used for degradation of soluble-glucans during mashing. 相似文献
5.
Anneli Ritala Kristian Aspegren Ulrika Kurtén Marjatta Salmenkallio-Marttila Leena Mannonen Riitta Hannus Veli Kauppinen Teemu H. Teeri Tor-Magnus Enari 《Plant molecular biology》1994,24(2):317-325
Transgenic, fertile barley (Hordeum vulgare L.) from the Finnish elite cultivar Kymppi was obtained by particle bombardment of immature embryos. Immature embryos were bombarded to the embryonic axis side and grown to plants without selection. Neomycin phosphotransferase II (NPTII) activity was screened in small plantlets. One out of a total of 227 plants expressed the transferred nptII gene. This plant has until now produced 98 fertile spikes (T0), and four of the 90 T0 spikes analyzed to date contained the nptII gene. These shoots were further analyzed and they expressed the transferred gene. From green grains, embryos were isolated and grown to plantlets (T1). The four transgenic shoots of Toivo (the T0 plant) produced 25 plantlets as T1 progeny. Altogether fifteen of these T1 plants carried the transferred nptII gene as detected with the PCR technique, fourteen of which expressed the nptII gene. The integration and inheritance of the transferred nptII gene was confirmed by Southern blot hybridization. Although present as several copies, the transferred gene was inherited as a single Mendelian locus into the T2 progeny. 相似文献
6.
Katriina Alhola Sven‐ Olof Ryding Hanna Salmenper Niels Juul Busch 《Journal of Industrial Ecology》2019,23(1):96-109
The objective of a circular economy (CE) is to maintain the value of products, materials, and resources in the economy by closing material loops and minimizing waste generation. In recent years, the role of public procurement has been recognized as an important, but as yet not fully exploited, opportunity by cities and municipalities in their transition toward circular societies. This study analyzed public procurement opportunities to promote CE. Different approaches and examples of circular public procurement were identified using case studies. In addition, opportunities to promote CE through sustainable and green public procurement policy were identified analyzing predefined sustainable or green public procurement criteria. The study concludes that public procurement can promote CE and related business models by setting criteria and requirements for the extension of product life spans, efficiency and/or intensity of use, and efficient cycling of biological or technical materials, as well as for the securing of clean and nonrisky cycles. Circular procurement can occur through the procurement of better‐quality products in circular terms, the procurement of new circular products, the use of business concepts that support the CE, and investments in circular ecosystems. Several sectors and product groups were identified as having potential for circular procurement, such as construction, waste, and wastewater management, transportation, food, and catering, furniture, and textiles. The study also suggests that the use of certain tools, such as performance‐based procurement, life cycle approach, and life cycle costing, as well as criteria concerning reuse and recycling of materials, could promote circular procurement. Market dialogue and cooperation between procurers and actors in the supply chains are important for the future development of circular procurement. 相似文献
7.
Hobbie Erik Alan Bendiksen Katriina Thorp Nathan R. Ohenoja Esteri Ouimette Andrew P. 《Ecosystems》2022,25(5):1207-1217
Ecosystems - A major functional division in ectomycorrhizal fungi is between taxa with hydrophobic ectomycorrhizae (strong proteolytic capabilities, deep nitrogen (N) acquisition, and extensive... 相似文献
8.
Up to four tetra-tert-butyl-1-[4-aminoacetamido)benzyl]diethylenetriaminetetrakis(acetato) derivatives of Fmoc glutamic acid (1) were attached to two steroids (17alpha-hydroxyprogesterone-3-O-carboxymethyloxime 2 and 1,3,5(10)-estratriene-3,16alpha,17beta-triol-6-one-6-O-carboxymethyloxime, 3)) on solid phase using an oligopeptide synthesizer. Upon deprotection and conversion to the corresponding europium(III) chelates, these steroid conjugates were used in DELFIA-based competitive fluoroimmunoassays. The more chelates conjugated to 17-alpha-hydroxyprogesterone, the more diluted antiserum could be used in an immunoassay for 17-alpha-hydroxyprogesterone, without any alteration of the measurement range. Hence, 17-alpha-hydroxyprogesterone tracers with several chelates are useful when a high serum dilution factor is desired i.e., when only a limited quantity of antiserum is available. The result demonstrates the suitability and usefulness of lanthanide(III) chelates as multilabels in bioaffinity assays. 相似文献
9.
Personality and anxiety disorders across species are affected by genetic and environmental factors. Shyness-boldness personality continuum exists across species, including the domestic dog, with a large within- and across-breed variation. Domestic dogs are also diagnosed for several anxiety-related behavioral conditions, such as generalized anxiety disorders, phobias, and separation anxiety. Genetic and environmental factors contributing to personality and anxiety are largely unknown. We collected questionnaire data from a Finnish family dog population (N = 3264) in order to study the associating environmental factors for canine fearfulness, noise sensitivity, and separation anxiety. Early life experiences and exercise were found to associate with anxiety prevalence. We found that fearful dogs had less socialization experiences (p = 0.002) and lower quality of maternal care (p < 0.0001) during puppyhood. Surprisingly, the largest environmental factor associating with noise sensitivity (p < 0.0001) and separation anxiety (p = 0.007) was the amount of daily exercise; dogs with noise sensitivity and separation anxiety had less daily exercise. Our findings suggest that dogs share many of the same environmental factors that contribute to anxiety in other species as well, such as humans and rodents. Our study highlights the importance of early life experiences, especially the quality of maternal care and daily exercise for the welfare and management of the dogs, and reveals important confounding factors to be considered in the genetic characterization of canine anxiety. 相似文献
10.
Luoto R Kinnunen TI Aittasalo M Kolu P Raitanen J Ojala K Mansikkamäki K Lamberg S Vasankari T Komulainen T Tulokas S 《PLoS medicine》2011,8(5):e1001036