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71.
Salinity induced changes in ethylene evolution, antioxidant defense system, N(2)-fixing efficiency and membrane integrity in relation to water and mineral status in chickpea (Cicer arietinum L.) nodules were studied under screen house conditions. At vegetative stage (55-65 DAS) plants were exposed to single saline irrigation (Cl(-) dominated) of levels 0, 2.5, 5.0 and 10.0dSm(-1) and sampled after 3d. The other set of treated plants was desalinized by flooding and the plants were sampled after further 3d. Water potential (Psiw) of leaf and osmotic potential (Psis) of leaf and nodules significantly decreased from -0.44 to -0.56MPa and from -0.65 to -1.15MPa and from -0.75 to -1.77MPa, respectively upon salinization. RWC of leaf and nodules also reduced from 86.05% to 73.30% and 94.70% to 89.98%, respectively. The decline in Psis of nodules was due to accumulation of proline and total soluble sugar. In comparison to control, the increase in ethylene (C(2)H(4)) production was 35-108% higher and correspondingly increase in 1-aminocycloprane-1-carboxylic acid (ACC) content (37-126%) and ACC oxidase activity (31-118%) was also noticed. Similarly, marked increase in H(2)O(2) (25-139%) and thiobarbituric acid substances (TBRAS, 11-133%) contents was seen. N(2)-fixing efficiency i.e. N(2)-ase activity, leghemoglobin and N contents of nodules declined significantly after saline irrigation. The induction in specific activity of antioxidant enzymes was confirmed by the increase in activity of superoxide dismutase, peroxidase, ascorbate peroxidase, glutathione reductase and glutathione transferase, whereas reverse was true for catalase. These activated enzymes could not overcome the accumulation of H(2)O(2) in nodules. Ascorbic acid content also declined from 20 to 38%, whereas Na(+)/K(+) ratio and Cl(-) content were significantly enhanced. Upon desalinization, a partial recovery in all above metabolic processes and water relations parameters was noticed. It is suggested that ethylene in relation to water status and lipid peroxidation and along with other metabolic processes has an important role in induced nodules senescence under salinity.  相似文献   
72.
Carnosic acid is a well-known antioxidant. Recently, it has been identified as modulator of nuclear factor erythroid 2-related factor 2 (Nrf2). The effect of carnosic acid in the context of cardiovascular disorders has not been studied. In the present study, we investigated the beneficial effect and the underlying cardioprotective mechanism of carnosic acid by using mouse model of isoproterenol (ISO)-induced myocardial stress. Elevated serum levels of Troponin I, CK-MB, LDH, SGOT and SGPT, and myofibrillar degeneration with necrotic damage, and the presence of epicardial inflammatory infiltrate (H & E staining) confirmed the ISO-induced myocardial stress. Myocardial content of vitamin C, reduced glutathione, glutathione peroxidase, glutathione reductase, glutathione S-transferase, NAD(P)H: quinine oxidoreductase 1, superoxide dismutase, catalase, nuclear translocation of Nrf2 and protein expression heme oxygenase-1 were evaluated. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and myocardial expression of cleaved caspase-3, caspase-9, p53, Bax, and Bcl-2 were investigated to assess the apoptotic cell death. Pretreatment with carnosic acid attenuated ISO-induced elevated serum levels of Troponin I, CK-MB, LDH, SGOT and SGPT, and histopathological alterations in heart. Moreover, carnosic acid enhanced the nuclear translocation of Nrf2 and up-regulated the phase II/antioxidant enzyme activities. Furthermore, TUNEL assay and apoptosis-related protein analysis indicated that carnosic acid prevented ISO-induced cardiomyocyte apoptosis. Isoproterenol-induced myocardial lipid peroxidation and protein oxidation were also significantly decreased by carnosic acid pretreatment. The overall results clearly indicate that therapeutic application of carnosic acid might be beneficial in treating cardiovascular disorders.  相似文献   
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Xylanase and xylooligosaccharides (XOS) are employed in food and feed industries. Though xylanase production from lignocellulosic materials (LCMs) by solid-state fermentation (SSF) is well known, the XOS formed during growth is not recovered due to its conversion to xylose by β-xylosidase and subsequent bacterial metabolism. A new strain, Bacillus subtilis KCX006, was exceptionally found to synthesize β-xylosidase-free endo-xylanase and multiple xylan debranching enzymes constitutively in the presence of LCMs. Absence of β-xylosidase resulted in accumulation of XOS during growth of KCX006 on LCMs. Therefore, this strain was used for simultaneous production of xylanase and XOS from agro-residues in solid-state fermentation (SSF). Partial purification of XOS from culture supernatant using activated charcoal followed by high-performance liquid chromatography (HPLC) analysis showed xylobiose to xylotetraose formed as the major products. Among various LCM substrates, wheat bran and groundnut oil-cake supported highest xylanase and XOS production at 2158 IU/gdw and 24.92 mg/gdw, respectively. The levels of xylanase and XOS were improved by 1.5-fold (3102 IU/gdw) and 1.9-fold (48 mg/gdw), respectively, by optimization of culture conditions.  相似文献   
76.
All-cause and cause-specific mortality among white U.S. men and women are analyzed using the NHANES I data (1971-1975) and epidemiologic follow-up to 1992, to examine the effect of physical stature on mortality, controlling for other confounding variables within a discrete-time framework. We find an association between mortality and both body mass index (BMI) and height, but the height effect is sensitive with respect to the age range under consideration. Although the resulting minimum-mortality BMI is higher than the widely accepted healthy range, the recent increase in weight implies that further gains in life expectancy are unlikely to derive from the anthropometry-mortality relationship.  相似文献   
77.
Raman spectra are obtained for the multilayer dispersion of rac-1,2,dioctadec-9′-cis-enyl-glycero-3-phosphorylcholine (dietherlecithin) in excess water. The CH stretching region was studied as a function of temperature and indicates that the multilayer dispersions undergo a liquid crystal to the gel phase transition at ?21 ± 4°C.  相似文献   
78.
The energy transfer at different trophic levels in a temperate lake ecosystem locally called Sar (lake) has been investigated. Total phytoplankton production in terms of energy fixation has been estimated at 3.2 × 106 cal m−2 y−1, out of which the fish harvest amounts to 2640 cal m−2 y−1. The conversion efficiency from phytoplankton to fish has been estimated at 0.082 %. Apart from other ecological parameters discussed in the paper, suggestions for the efficient use of other available energy from the system has been highlighted.  相似文献   
79.
Raman spectra of polycrystalline stearic acid-d0, stearic acid-d35, 16:16-d2-18:18:18-d3-stearic acid, 18:18:18-d3-stearic acid, 17:17-d2-stearic acid, 17-d1-stearic acid, 16:16-d2-stearic acid, 12:12-d2-stearic acid and 12-d1-stearic acid have been obtained for the region containing the C-D and C-H stretching vibrations. Assignments of the methyl, methyl-d3, methylene, methylene-d2 and methylene-d1 stretching vibrations are discussed.  相似文献   
80.
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