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1.
Hussein  Manal T.  Mokhtar  Doaa M.  Hassan  A. H. S 《Protoplasma》2020,257(2):353-369
Protoplasma - The adrenal glands of 15 adult Soay rams were used to study the effect of melatonin on their vascular elements and cellular organization. A significant increase in the cross-sectional...  相似文献   
2.
The study investigates the effects of the 11+ and HarmoKnee injury prevention programmes on knee strength in male soccer players. Under-21-year-old players (n=36) were divided equally into: the 11+, HarmoKnee and control groups. The programmes were performed for 24 sessions (20-25 min each). The hamstrings and quadriceps strength were measured bilaterally at 60°·s-1, 180°·s-1 and 300°·s-1. The concentric quadriceps peak torque (PT) of the 11+ increased by 27.7% at 300°·s-1 in the dominant leg (p<0.05). The concentric quadriceps PT of HarmoKnee increased by 36.6%, 36.2% and 28% in the dominant leg, and by 31.3%, 31.7% and 20.05% at 60°·s-1, 180°·s-1 and 300°·s-1 in the non-dominant leg respectively. In the 11+ group the concentric hamstring PT increased by 22%, 21.4% and 22.1% at 60°·s-1, 180°·s-1 and 300°·s-1, respectively in the dominant leg, and by 22.3%, and 15.7% at 60°·s-1 and 180°·s-1, in the non-dominant leg. In the HarmoKnee group the hamstrings in the dominant leg showed an increase in PT by 32.5%, 31.3% and 14.3% at 60°·s-1, 180°·s-1 and 300°·s-1, and in the non-dominant leg hamstrings PT increased by 21.1% and 19.3% at 60°·s-1 and 180°·s-1 respectively. The concentric hamstrings strength was significantly different between the 11+ and control groups in the dominant (p=0.01) and non-dominant legs (p=0.02). The HarmoKnee programme enhanced the concentric strength of quadriceps. The 11+ and HarmoKnee programmes are useful warm-up protocols for improving concentric hamstring strength in young professional male soccer players. The 11+ programme is more advantageous for its greater concentric hamstring strength improvement compared to the HarmoKnee programme.  相似文献   
3.
Three new polyketides (-)-1 , (+)-1 , and 2 ) were isolated from the EtOAc extract of the fungus Embellisia eureka, an endophyte of the Moroccan plant Cladanthus arabicus (Asteraceae). The structures of these new compounds were determined on the basis of one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configurations of (-)-1 , (+)-1 , and 2 were determined by TDDFT ECD calculations of solution conformers, online HPLC-ECD analysis, and the modified Mosher method. Chirality 25:250–256, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
4.
In the present work, separate and combined effects of excessive potassium and magnesium deficiency on safflower (Carthamus tinctorius) were studied. Four treatments were considered: C (control treatment: complete medium containing 1.5 mM Mg), +KCl (excessive potassium treatment: complete medium added with 60 mM KCl), ?Mg (Mg-deficient treatment: containing 0.1 mM Mg), and DS (double stress treatment: Mg-deficient medium (0.1 mM Mg) added with 60 mM KCl. Excessive potassium effect on plant growth was more pronounced than that of Mg deficiency. The two stresses impaired differently plant organs; KCl application affected more roots than shoots, whereas Mg deficiency reduced only leaf biomass. Gas exchange and pigment concentrations and patterns were severely impaired by KCl and mainly by interactive effects of the two stresses. This led to obvious lipid peroxidation and electrolyte leakage. Mg deficiency did not induce lipid peroxidation and electrolyte leakage, but as applied with excessive potassium, it doubled the effect of the latter. Mineral analyses showed that major cation nutrition was disturbed by KCl and combined stresses and at a lower level by magnesium deficiency. Plants did not show an enhanced selectivity of Mg and Ca over K but they improved their use efficiencies.  相似文献   
5.
Dispersal and mating features strongly influence the evolutionary dynamics and the spatial genetic structure (SGS) of marine populations. For the first time in a marine invertebrate, we examined individual reproductive success, by conducting larval paternity assignments after a natural spawning event, combined with a small‐scale SGS analysis within a population of the gorgonian Paramuricea clavata. Thirty four percent of the larvae were sired by male colonies surrounding the brooding female colonies, revealing that the bulk of the mating was accomplished by males from outside the studied area. Male success increased with male height and decreased with increasing male to female distance. The parentage analyses, with a strong level of self‐recruitment (25%), unveiled the occurrence of a complex family structure at a small spatial scale, consistent with the limited larval dispersal of this species. However, no evidence of small scale SGS was revealed despite this family structure. Furthermore, temporal genetic structure was not observed, which appears to be related to the rather large effective population size. The low level of inbreeding found suggests a pattern of random mating in this species, which disagrees with expectations that limited larval dispersal should lead to biparental inbreeding. Surface brooding and investment in sexual reproduction in P. clavata contribute to multiple paternity (on average 6.4 fathers were assigned per brood), which enhance genetic diversity of the brood. Several factors may have contributed to the lack of biparental inbreeding in our study such as (i) the lack of sperm limitation at a small scale, (ii) multiple paternity, and (iii) the large effective population size. Thus, our results indicate that limited larval dispersal and complex family structure do not necessarily lead to biparental inbreeding and SGS. In the framework of conservation purposes, our results suggested that colony size, proximity among colonies and the population size should be taken into consideration for restoration projects.  相似文献   
6.
Journal of Physiology and Biochemistry - Gamma-tocotrienol (GTT) and hydroxychavicol (HC) exhibit anticancer activity in glioma cancer cells, where the combination of GTT + HC was shown to be more...  相似文献   
7.
8.
Black nightshade (Solanum nigrum, S. nigrum L.) and red nightshade ( Solanum villosum, S. villosum Mill.) are medicinal plants from the Solanaceae family that synthesize glycoalkaloids and other secondary metabolites. To recognize the potential insecticide activity of these compounds, leaf extracts (containing glycoalkaloid and methanol fractions) were tested for enzyme inhibition, antifeedant activity and toxicity. For in‐vitro glutathione S‐transferase (GST) inhibition activity, we used insecticide‐resistant Colorado potato beetle, Leptinotarsa decemlineata ( L. decemlineata; Say) midgut and fat‐body homogenate. In‐vivo toxicity and the antifeedant activity were performed using larval bioassays. The methanol extracts had greater GST inhibitory activity compared to the glycoalkaloids, as well as greater 2nd instar larvae mortality and antifeedant activity. Furthermore, the green leaf volatile compound, cis‐hex‐3‐enyl acetate, at the concentration of 5 ppm, caused 50% mortality of 2nd instar larvae. Our findings suggest the potential usefulness of S. nigrum and S. villosum extracts to control L. decemlineata.  相似文献   
9.
Effects of salinity, temperature and their interactions on the rate and final percentage of germination were evaluated for two populations (Msarref, Oued dkouk) of the invasive glycophyte Lotus creticus Linné, grown under arid environmental conditions of the Tunisia. Seeds that were not treated with NaCl germinated well in a wide range of temperatures. For both populations, maximum germination occurred in distilled water at 25°C and lowest germination for all salinities was at 35°C. Germination was substantially delayed and significantly reduced with an increase in NaCl to levels above 300 mm . Compared to the Oued dkouk population, final germination and germination rate of the Msarref population was completely inhibited at 300 mm NaCl. The interactive effect of temperature and NaCl concentration on final germination and germination rate was significant (P < 0.01), indicating that the germination response to salinity depended on temperature. The inhibition of Oued dkouk population seed germination at high salt concentration was mostly due to osmotic effects while ionic effects were noted at Msarref population. The germination behaviour of the Oued dkouk population would therefore imply adaptive mechanisms to saline environments, while in the Msarref population such mechanisms seem to be absent. Since seed germination is more sensitive to salinity stress than the growth of established plants, the greater tolerance to salinity of Oued dkouk population would be an adaptive feature of this population to saline environment.  相似文献   
10.
Nodule conductance to O2 diffusion has been involved as a major factor of the inhibition of N2 fixation by soil salinity that severely reduces the production of grain legumes. In order to determine the effect of this constraint on the nodule conductance, oxygen uptake by the nodulated roots of Cicer arietinum was measured by recording the concentration of O2 as a function of pO2 in a gas-tight incubator. After germination and inoculation with the strain Mesorhizobium ciceri UPMCa7, the varieties Amdoun 1 and INRAT 93-1 were hydroponically grown in a glasshouse on 1L glass bottles filled with nutrient solution containing 25 mM NaCl. Salinity induced a marked decrease in shoot (30% versus 14%), root (43% versus 20%), and nodule biomass (100% versus 43%) for Amdoun 1 relative to INRAT 93-1. Although salinity completely prevented nodule formation in the sensitive variety Amdoun 1, nodule number and biomass were higher in the first than in the second variety in the absence of salt. This effect was associated with a significantly higher O2 uptake by nodulated root (510 versus 255 micromol O2 plant(-1)h(-1)) and nodule conductance (20 versus 5 microm s(-1)) in Amdoun 1 than in INRAT 93-1. Salinity did not significantly change the nodule conductance and nodule permeability for INRAT 93-1. Thus, the salt tolerance of this variety appears to be associated with stability in nodule conductance and the capacity to form nodules under salt constraint.  相似文献   
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