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81.
Coping with pressure and anxiety is an ineluctable demand of sports performance. Heart rate variability (HRV) Biofeedback
(BFB) shall be used as a tool for self regulating physiological responses resulting in improved psycho physiological interactions.
For further analysis, the present study has been designed to examine the relationship between anxiety and performance and
also effectiveness of biofeedback protocol to create stress-eliciting situation in basketball players. Thirty basketball players
of university level and above (both male and female) aged 18–28 years, who scored a minimum of 20 in state trait anxiety inventory,
were randomly divided into three equal groups- Experimental (Biofeedback) group, Placebo group and Control (No Treatment)
group. The BFB group received HRV BFB training for 10 consecutive days for 20 min that included breathing at individual’s
resonant frequency through a pacing stimulus; Placebo group was shown motivational video clips for 10 consecutive days for
10 min, whereas No Treatment Control group was not given any intervention. Two way repeated measure ANOVA was applied to analyze
the differences within and between the groups. Anxiety, coping self-efficacy, heart rate variability, respiration rate, and
performance (dribbling, passing and shooting) at session 1, 10 and 1 month follow up were statistically significant in each
group along with interaction of group and time (p < 0.001). Also, all the measures showed statistically significant inter group difference (p < 0.05). The findings are harmonious with existing data on HRV BFB as a strategy for dealing with anxiety. The Placebo group
showed improvement in self efficacy and performance post training. The Control group showed no change in any variable except
performance. The results of the study support the idea that HRV BFB lowers the anxiety and thus there seems to be a potential
association between HRV BFB and performance optimization. 相似文献
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Salinity has plagued soil fertility and drastically affected growth and survival of glycophytes in irrigated regions of the
world since the beginning of recorded history. It is particularly common in arid and semi-arid areas where evapotranspiration
exceeds annual precipitation, and where irrigation is therefore necessary to meet crop water needs. Salt buildup in the soils
and groundwater has threatened its productivity and sustainability. Plant responses to salt stress include an array of changes
at the molecular, biochemical and physiological levels. Salt stress involves a water deficit induced by the salt concentration
in the rhizosphere, resulting in disruption of homeostasis and ion distribution in the cell and denaturation of structural
and functional proteins. As a consequence, salinity stress often activates cell signaling pathways including those that lead
to synthesis of osmotically active metabolites, specific proteins, and certain free radical scavenging enzymes that control
ion and water flux and support scavenging of oxygen radicals or chaperones. ROS detoxification forms an important defense
against salt stress. Legumes are a key component of sustainable agriculture and can offer many economic and environmental
benefits if grown more widely in crop rotations because of their ability to fix nitrogen in the root nodules in a symbiotic
interaction with soil rhizobia. Due to their capacity to grow on nitrogen-poor soils, they can be efficiently used for improving
saline soil fertility and help to reintroduce agriculture to these lands. However, in legumes, salt stress imposes a significant
limitation of productivity related to the adverse effects on the growth of the host plant, the root-nodule bacteria, symbiotic
development and finally the nitrogen fixation capacity. This paper reviews responses of legumes to salinity stress with emphasis
on physiological and biochemical mechanisms of salt tolerance. 相似文献
86.
The association of structurally disordered proteins with a number of diseases has engendered enormous interest and therefore
demands a prediction method that would facilitate their expeditious study at molecular level. The present study describes
the development of a computational method for predicting disordered proteins using sequence and profile compositions as input
features for the training of SVM models. First, we developed the amino acid and dipeptide compositions based SVM modules which
yielded sensitivities of 75.6 and 73.2% along with Matthew’s Correlation Coefficient (MCC) values of 0.75 and 0.60, respectively.
In addition, the use of predicted secondary structure content (coil, sheet and helices) in the form of composition values
attained a sensitivity of 76.8% and MCC value of 0.77. Finally, the training of SVM models using evolutionary information
hidden in the multiple sequence alignment profile improved the prediction performance by achieving a sensitivity value of
78% and MCC of 0.78. Furthermore, when evaluated on an independent dataset of partially disordered proteins, the same SVM
module provided a correct prediction rate of 86.6%. Based on the above study, a web server (“DPROT”) was developed for the
prediction of disordered proteins, which is available at . 相似文献
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Y.S. Chauhan V.S. Rathore G.K. Garg Aruna Bhargava 《Biochemical and biophysical research communications》1978,83(4):1237-1245
An enzyme activity which brings about a rapid indole disappearance has been detected in cell free extracts of maize ( L.) leaves. The indole utilization by this enzyme system is not dependent on L-serine and pyridoxal phosphate. It does not result in incorporation of (5-3H) indole or (1-14C) serine into tryptophan. There was no net tryptophan synthesis concomittant with indole disappearance. The enzyme activity is strongly inhibited by dithionite and diethyl-dithiocarbamate. The inhibition by the latter could be specifically removed by Cu2+. The activity of dialyzed enzyme could be restored by addition of Cu2+ and FAD. The products of indole oxidation were characterized as anthranilic acid and anthranil (2,1-benzisooxazole). The activity of the indole oxidizing system was 2 to 3 times higher in normal maize varieties (Ganga-2 and Ganga-5) than in Opaque-2. 相似文献
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