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961.
962.
Eva A. Andersson Johnny Nilsson Zhijia Ma Alf Thorstensson 《European journal of applied physiology and occupational physiology》1997,75(2):115-123
The purpose of this study was to provide objective information on the involvement of different abdominal and hip flexor muscles
during various types of common training exercises used in rehabilitation and sport. Six healthy male subjects performed altogether
38 different static and dynamic training exercises – trunk and hip flexion sit-ups, with various combinations of leg position
and support, and bi- and unilateral leg lifts. Myoelectric activity was recorded with surface electrodes from the rectus abdominis,
obliquus externus, obliquus internus, rectus femoris, and sartorius muscles and with indwelling fine-wire electrodes from
the iliacus muscle. The mean electromyogram amplitude, normalised to the highest observed value, was compared between static
and dynamic exercises separately. The hip flexors were highly activated only in exercises involving hip flexion, either lifting
the whole upper body or the legs. In contrast, the abdominal muscles showed marked activation both during trunk and hip flexion
sit-ups. In hip flexion sit-ups, flexed and supported legs increased hip flexor activation, whereas such modifications did
not generally alter the activation level of the abdominals. Bilateral, but not unilateral, leg lifts required activation of
abdominal muscles. In trunk flexion sit-ups an increased activation of the abdominal muscles was observed with increased flexion
angle, whereas the opposite was true for hip flexion sit-ups. Bilateral leg lifts resulted in higher activity levels than
hip flexion sit-ups for the iliacus and sartorius muscles, while the opposite was true for rectus femoris muscles. These data
could serve as a basis for improving the design and specificity of test and training exercises.
Accepted: 12 August 1996 相似文献
963.
Functional Characterization of Human Nucleosome Assembly Protein-2 (NAP1L4) Suggests a Role as a Histone Chaperone 总被引:2,自引:0,他引:2
Pedro Rodriguez David Munroe Dirk Prawitt Lee Lee Chu Eva Bric Jungho Kim Laura H. Reid Chris Davies Hitoshi Nakagama Ralf Loebbert Andreas Winterpacht Mary-Jane Petruzzi Michael J. Higgins Norma Nowak Glen Evans Tom Shows Bernard E. Weissman Bernhard Zabel David E. Housman Jerry Pelletier 《Genomics》1997,44(3):253
964.
F. Vánky Noémi Nagy Christina Hising Kerstin Sjövall Eva Klein 《Cancer immunology, immunotherapy : CII》1997,43(6):317-323
We tested 20 human carcinoma samples for the production of transforming growth factor β (TGFβ) in vitro. Tumour cell suspensions
without obvious contamination with non-malignant cells were kept in culture conditions for 16 h and their supernatants were
added to CCL-64 cells. The proliferation of these cells is inhibited by TGFβ. According to this assay, the supernatants contained
both active and latent TGFβ. In addition, the supernatants were found to suppress the spontaneous cytotoxic function and activation
of T-cell-enriched lymphocyte populations. A specific monoclonal antibody (mAb) counteracted these effects and therefore we
concluded that they were mediated to a large extent by TGFβ. In line with the results obtained with the supernatants, activation
of lymphocytes could also be inhibited by tumour cells and their inhibitory effect was weaker in the presence of the TGFβ-specific
mAb. It is important to note that, when TGFβ-specific mAb was added to autologous mixed lymphocyte/tumour cell cultures, lymphocyte
activation occurred more often. These results thus substantiate the assumption that production of TGFβ may help the survival
of potentially immunogenic tumour cells in immunocompetent patients.
Received: 21 August 1996 / Accepted: 12 November 1996 相似文献
965.
Increased Levels of Monodehydroascorbate Radical in UV-B-Irradiated Broad Bean Leaves 总被引:1,自引:0,他引:1
Light-induced monodehydroascorbate (MDA) radical productionwas not detectable by EPR spectroscopy in untreated broad beanleaves, but it was observed after exposing the leaves to UV-B(280320 nm) irradiation. After this pre-treatment, alow level of MDA radicals was also detectable without illumination.Light-induced MDA, MDA production in the dark, oxygen evolution,quantum yield of PSII as measured by Chi fluorescence, MDA producingand reducing enzyme activities were determined and comparedin leaves after irradiation with various doses of UV-B. Ourresults suggest that UV-B irradiation disturbs the balance ofMDA radical production and reduction, resulting in increasedlight induced MDA signal. The enhancement of ascorbate photooxidationat the UV-B damaged donor side of PSII appears as a major factorin this process. (Received November 22, 1996; Accepted March 25, 1997) 相似文献
966.
Pavel Vesely Luboslava Pavlikova Jiri Plachy Katerina Trejbalova Jiri Hejnar Eva Matouskova Jürgen Bereiter-Hahn 《Experimental Biology Online》1997,2(6):1-74
In spontaneously metastasizing rat RPS sarcoma cells, a 3D structure of oblique F-actin cables was observed which was associated with active cell migration in vitro. This led us to further comparative investigations of several other neoplastic and normal cell populations in vitro for F-actin structures using confocal laser scanning microscopy (CLSM). Various forms of F-actin cytoskeleton were observed and the incidence of podosome-related contact structures appeared to be associated with malignancy, interpreted as metastatic capacity. 相似文献
967.
Mona Esbj?rnsson-Liljedahl Kristina Bodin Eva Jansson 《Journal of applied physiology》2002,93(3):1075-1083
It was hypothesized that the reduction of high-energy phosphates in muscle after repeated sprints is smaller in women than in men. Fifteen healthy and physically active women and men with an average age of 25 yr (range of 19-42 yr) performed three 30-s cycle sprints (Wingate test) with 20 min of rest between sprints. Repeated blood and muscle samples were obtained. Freeze-dried pooled muscle fibers of types I and II were analyzed for high-energy phosphates and their breakdown products and for glycogen. Accumulation of plasma ATP breakdown products, plasma catecholamines, and blood lactate, as well as glycogen reduction in type I fibers, was all lower in women than in men during sprint exercise. Repeated sprints induced smaller reduction of ATP and smaller accumulation of IMP and inosine in women than in men in type II muscle fibers, with no gender differences in changes of ATP and its breakdown products during the bouts of exercise themselves. This indicates that the smaller ATP reduction in women than in men during repeated sprints was created during recovery periods between the sprint exercises and that women possess a faster recovery of ATP via reamination of IMP during these recovery periods. 相似文献
968.
Frost hardening of seedlings of Scots pine (Pinus sylvestris) at a non-freezing temperature of 4°C resulted in a 2-fold increase of the acyl lipids of the needles. This was because of increases in phospholipids and triglycerides. The galactolipid content of the needles was almost the same in unhardened and frost-hardened seedlings. In unhardened seedlings the mol ratio of monogalactosyl diacylglycerol (MGDG) to digalactosyl diacylglycerol (DGDG) was 1.7 ± 0.3 and 0.9 ± 0.2 in needles and isolated thylakoids, respectively. Corresponding ratios for frost-hardened seedlings were 1.5 ± 0.2 and 0.3 ± 0.03. The lower ratios found in isolated thylakoids, particularly in thylakoids from frost-hardened seedlings, are suggested to depend on the enzyme galactolipid: galactolipid galactosyltransferase being active during the isolation procedure. This is deduced from the result that the content of MGDG decreased and that of DGDG and 1.2 diglycerides increased. Needles of Scots pine also contain phospholipidase D. This enzyme was active during thylakoid preparation, particularly after frost hardening, as judged from the large amount of phosphatidic acid found the in thylakoid fraction isolated from frost-hardening needles. The fatty acid composition of the acyl lipids showed no major changes due to hardening at non-freezing temperature. 相似文献
969.
Local and regional assessments of the impacts of plant invaders on vegetation structure and soil properties of Mediterranean islands 总被引:7,自引:0,他引:7
Montserrat Vilà Marc Tessier Carey M. Suehs Giuseppe Brundu Luisa Carta Alexandros Galanidis Philip Lambdon Manuela Manca Frédéric Médail Eva Moragues Anna Traveset reas Y. Troumbis Philip E. Hulme 《Journal of Biogeography》2006,33(5):853-861
Aims Although biological invasions occur throughout the world, and some invaders are widespread in many habitats, few studies on the ecological impact of invaders have examined multiple sites. We tested how the impact of three widespread plant invaders changed depending on the identity of the species and the invaded island. We also tested whether relative species loss was lower in species‐rich communities than in species‐poor ones. Location We conducted floristic surveys and soil analyses in eight Mediterranean Basin islands: Crete and Lesbos (Greece), Sardinia (Italy), Corsica, Bagaud and Porquerolles (France), and Mallorca and Menorca (Spain). Methods We compared native species richness and diversity, proportion of life forms, soil percentage nitrogen, percentage organic carbon, C/N, and soil pH in nearby paired plots of 2 × 2 m: one control and one invaded by either the deciduous tree Ailanthus altissima, the succulent subshrubs Carpobrotus spp. or the annual geophyte Oxalis pes‐caprae, across eight Mediterranean Basin islands. Results On average, the presence of invaders reduced species diversity, Carpobrotus spp. exhibiting the largest impact and Oxalis the least. However, the relative impact was island‐dependent, and was positively but weakly associated with the species richness of the recipient community. Therophytes were the life form that experienced the largest decrease across islands. The effects of invasion on soil properties were very variable. Total N changed (increased) only in plots invaded by Ailanthus, significantly decreasing the C/N ratio. The presence of this tree increased soil pH, whereas the opposite was found in plots invaded by the other two species. Organic C increased in plots invaded by Ailanthus and Carpobrotus species. Main conclusions By conducting an analysis at multiple sites, we found that the three plant invaders had an impact on plant community structure not entirely concordant with changes in soil properties. The impacts depended on the identity of the species and of the invaded island, suggesting that impact of invaders is context‐specific. The impact in terms of species loss was not lower in species‐rich than in species‐poor communities. 相似文献
970.