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991.
992.
We hypothesized that resistance training with combined eccentric and concentric actions, and concentric action only, should yield similar changes in muscular strength. Subjects in a free weight group trained three times a week for 12 wk with eccentric and concentric actions (FW, n = 16), a second group trained with concentric-only contractions using hydraulic resistance (HY; n = 12), and a control group did not train (n = 11). Training for FW and HY included five sets of supine bench press and upright squat at an intensity of 1-6 repetition maximum (RM) plus five supplementary exercises at 5-10 RM for a total of 20 sets per session for approximately 50 min. Testing at pre-, mid-, and posttraining included 1) 1 RM bench press and squat with and 2) without prestretch using free weights; 3)isokinetic peak force and power for bench press and squat at 5 degrees/s, and isotonic peak velocity and power for bench press with 20-kg load and squat with 70-kg load; 4) hydraulic peak bench press force and power, and peak knee extension torque and power at fast and slow speeds; and 5) surface anthropometry (fatfolds and girths to estimate upper arm and thigh volume and muscle area). Changes in overall fatness, muscularity, and muscle + bone cross-sectional area of the limbs did not differ between groups (P greater than 0.05). Improvements in free weight bench press and squat were similar (P greater than 0.05) in FW (approximately 24%) and HY (approximately 22%, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
Agents known to influence Ca2+ homeostasis affected significantly the vegetative growth and starvation-induced conidiation ofTrichoderma viride. Ca2+ in millimolar concentrations stimulated both growth and conidiation; a Ca2+ deprivation of the fungus by the chelation of extracellular Ca2+ (not Mg2+ or divalent trace metals) with EGTA (ethyleneglycolbis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) restricted both the
vegetative growth rate and starvation-induced conidiation. Both processes were affected by either Ca2+ or EGTA with different efficiencies. Divalent cations (Sr2+, Ba2+, Co2+, Ni2+, Mg2+, Cd2+, Cu2+, Mn2+) and La3+ (inorganic Ca2+ blockers) in millimolar concentrations exerted complex (stimulatory, inhibitory, or biphasic) effects on growth and conidiation.
In general, their effects on the two processes were mutually different either qualitatively, or quantitatively, or both. Organic
Ca2+ antagonists (verapamil and dihydropyridines) inhibited the vegetative growth. The results show that Ca2+ is required for vegetative growth and conidiation, and that different Ca2+-dependent mechanisms may be involved in the two processes. Divalent cations could serve as a tool for investigating the relationship
between growth and conidiation. 相似文献
994.
H. Mönkemann U. Hölker O. Golubnitchaya-Labudová H. Lichtenberg-Fraté M. Höfer 《Folia microbiologica》1996,41(5):445-448
We describe an evidence for the existence of a ligninase isoenzyme H8 in the deuteromyceteFusarium oxysporum on the genomic as well as on the RNA level. 相似文献
995.
The chromosomes of the European eel Anguilla anguilla have been analyzed with a replication banding technique from lymphocyte cultures treated with 5-BrdU. This technique allows us to identify with high resolution the individual chromosome pairs and to differentiate classes of chromatin by the order of replication. The replication banding obtained on the chromosomes of European eel can be related with the structural bands described in this species. 相似文献
996.
Three fluorescent probes, tetramethyl rhodamine ethyl ester (TMRE), 3,3′-dipropylthiacarbocyanine iodide (diS-C3(3)) and 3,3′-dipropyloxacarbocyanine iodide (diO-C3(3)), were tested for their suitability as fluorescent indicators of membrane potential inSaccharomyces cerevisiœ in studies performed by flow cytometry. For all these dyes the intensity of fluorescence of stained cells increased with
probe concentration in the range of 60–3000 nmol/L. The optimum staining period was 15–20 min for diS-C3(3). Depolarization of cells by increased extracellular potassium level and by valinomycin elicited with all probes a drop
in fluorescence intensity. In some yeast batches this depolarization was accompanied by a separation of subpopulations with
different fluorescence properties. 相似文献
997.
Vanadate (NaVO3) in concentrations between 0.1–3.0 mmol/L inhibited the production of secondary metabolites (SMs) of strains of the following
species:Trichoderma viride, Penicillium purpurogenum, Penicillium citrinum, Talaromyces avellaneus, andVerticillium psalliotœ. Growth was either not affected by NaVO3, or the inhibition of the SM production occurred at lower NaVO3, concentrations than that of the growth. Thus, at some NaVO3 concentration the SM production was inhibited but the growth remained unaffected. The results suggest that NaVO3 exerts a specific action either on the SM biosynthetic pathway(s) or on the export of SMs from cells. 相似文献
998.
The effects of subinhibitory concentrations (1/4, 1/8, 1/16 of the MIC) of quinolones (ciprofloxacin, enoxacin, nalidixic
acid, norfloxacin, ofloxacin, pefloxacin), aminoglycosides (amikacin, gentamicin, netilmicin, streptomycin, tobramycin), β-lactams
(aztreonam, ceftazidime, imipenem, ticarcilin) and macrolides (erythromycin, roxitromycin) on the excretion of alginate by
aP. aeruginosa strain were studied. Both β-lactam and macrolide antibiotics were found ineffective at the concentrations tested, except
erythromycin and imipenem at 1/4 MIC. Aminoglycosides at a concentration of 1/4 MIC reduced most effectively the excretion
of alginate. Quinolones were also effective at this sub-MIC; 1/16 MIC was ineffective with all antibiotics or stimulated the
production of alginate. 相似文献
999.
González Mariela Montoya Rolando Candia Arturo Gómez Patricia Cisternas Manuel 《Hydrobiologia》1996,326(1):229-234
The extreme phenotypic variability recognized among the species of Gracilaria has highlighted the need for the application of refined methods to help solve taxa identifications. In Chile, there still exists uncertainty about the exact number of Gracilaria species. Our investigations are centered on DNA analyses of morphotypes collected from different geographical locations, namely Lenga and Isla Santa María, Region VIII (36°00 S to 38°00 S), and Maullín, Region X (39°30 S to 43°40 S). These two regions of Chile are considered as areas of confluence of G. chilensis, G. verrucosa, and a species of Gracilariopsis. In this study four morphotypes, from a natural bed located in Maullín, were analyzed for RFLP of plastid DNA and the results compared with data of four morphotypes from a bed in Lenga. The DNA banding patterns from each enzyme digest were identical irrespective of morphotypes and/or locations. In an attempt to unravel the nature of the morphological differences found among Lenga and Maullín morphotypes, RAPD analyses of nuclear DNA were also performed; however, no polymorphism has been found yet. Therefore, the data of this study, as well as concurrent data from preliminary interfertility tests, suggest that all morphotypes belong to a single taxon, Gracilaria chilensis.Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas 相似文献
1000.
A. García Diez L. Rivas Soriano F. de Pablo Dávila E. L. García Diez 《International journal of biometeorology》1996,39(3):148-150
In earlier papers a qualitative and quantitative model was developed for predicting the number of forest fires occurring per day. This model permits the forecast at 00.00 hours Universal Time Convention (UTC) of any day (d), the number of forest fires per day for a range of several days (d tod+5) over a particular region. Input data are the number of forest fires in the region during two preceding days (d–2 andd–1) and the type of day (real and evaluated from radiosonde ford–2,d–1,d and predicted from meteorological medium-range forecasts, i.e. of European Centre, ford+1,d+2,d+3,d+4 andd+5. As this model requires data obtained by radiosonde, particularly temperatures and geopotentials at 850 and 700 hPa and dew points (or specific humidity) at 850 hPa, this study investigates the spatial validity of the model in relation to the distance from the radiosonde station (RS). The highest quality forecast is obtained for the region immediately surrounding the RS, and diminishes with increasing distance from it, this being due to the data obtained from the RS not being representative of the atmospheric column over the region. Hence, the derivation of the critical distance for a particular quality level of measurement. Conversely, fixed quality level implies a specific separation between RS and the region for the prediction, with a higher predictive quality implying a shorter distance. 相似文献