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51.
SYNTHESIS OF RNA IN DEVELOPING RAT BRAIN IN VITRO   总被引:1,自引:0,他引:1  
—Incorporation of [8-14C]adenine into a rapidly-labelled fraction of RNA derived from the nucleus, and into a cytoplasmic RNA of high molecular weight was studied in brain slices from new born rats. The kinetic behaviour of the two fractions of RNA was compatible with a precursor-product relationship between them. The change in the specific activity of adenine and the reduction of radioactivity in prelabelled RNA of brain slices in the presence of actinomycin D, suggest that the observed degradation of nuclear RNA is not due to random changes, but is limited to a relatively small fraction, presumably messenger RNA.  相似文献   
52.
The rate and efficiency of decolorization of poly R-478- or Remazol Brilliant Blue R (RBBR)-containing agar plates (200 μg g−1) were tested to evaluate the dye degradation activity in a total of 103 wood-rotting fungal strains. Best strains were able to completely decolorize plates within 10 days at 28 °C. Irpex lacteus and Pleurotus ostreatus were selected and used for degradation of six different groups of dyes (azo, diazo, anthraquinone-based, heterocyclic, triphenylmethane, phthalocyanine) on agar plates. Both fungi efficiently degraded dyes from all groups. Removal of RBBR, Bromophenol blue, Cu-phthalocyanine, Methyl red and Congo red was studied with I. lacteus also in liquid medium. Within 14 days, the following color reductions were attained: RBBR 93%, Bromophenol blue 100%, Cu-phthalocyanine 98%, Methyl red 56%, Congo red 58%. The ability of I. lacteus to degrade RBBR spiked into sterile soil was checked, the removal being 77% of the dye added within 6 weeks. The capacity of selected white rot fungal species to remove efficiently diverse synthetic dyes from water and soil environments is documented.  相似文献   
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Haloarchaea are predominant in the salt crystallizers of the Rann of Kutch when the concentration of salts approaches saturation levels. The obligate and extreme halophilic archaeon 3A1-DGR, isolated from a salt crystallizer pond of the Little Rann of Kutch, India, needs minimum of 10 % NaCl in the growth medium. To understand the mechanism(s) of osmotolerance and adaptation at extreme osmolarity, and to mine relevant gene(s), the genome of this haloarchaeon, 3A1-DGR, was sequenced. We report here, the 2.88 Mb draft genome sequence of the haloarchaeon 3A1-DGR, with G+C content of 68 % and the possible involvement of 43 genes in stress tolerance. Further studies of the genome of this haloarchaeon would be required to identify gene(s) that might be responsible for imparting extreme osmotolerance.  相似文献   
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The major damaging factor during and after the ischemic/hypoxic insult is the generation of free radicals, which leads to apoptosis, necrosis, and ultimately cell death. Rubia cordifolia (RC), Fagonia cretica linn (FC), and Tinospora cordifolia (TC) have been reported to contain a wide variety of antioxidants and have been in use in the eastern system of medicine for various disorders. Hippocampal slices were subjected to oxygen-glucose deprivation (OGD) and divided into three groups, control, OGD, and OGD+drug treated. Cytosolic reduced glutathione (GSH), nitric oxide [NO, measured as nitrite (NO2)]. EPR was used to establish the antioxidant effect of RC, FC, and TC with respect to superoxide anion (O*2-), hydroxyl radicals (*OH), nitric oxide (NO) radical, and peroxynitrite anion (ONOO-) generated from pyrogallol, menadione, DETA-NO, and Sin-1, respectively. RT-PCR was performed for the three herbs to assess their effect on the expression of gamma-glutamylcysteine ligase (GCLC), iNOS, and GAPDH gene expression. All the three herbs were effective in elevating the GSH levels and expression of the GCLC. The herbs also exhibited strong free radical scavenging properties against reactive oxygen and nitrogen species as revealed by electron paramagnetic resonance spectroscopy, diminishing the expression of iNOS gene. RC, FC, and TC therefore attenuate oxidative stress mediated cell injury during OGD and exert the above effects at both the cytosolic as well as at gene expression levels and may be effective therapeutic tool against ischemic brain damage.  相似文献   
57.
Using radioactive iodine, the effect of 1 month's yogic exercises has been investigated on the thyroid function of subjects resident at sea level (SL) specially after their exposure to high altitude (HA). The results have been compared with a group of SL subjects who underwent physical training (PT) exercises for the same duration. Ten healthy male volunteers in the age range of 20–30 years were used as test subjects in this study with each serving as his own control. The subjects were randomly divided into two groups of 5 each. One group practised hatha yogic exercises, while the other group performed the regular PT exercises. The thyroidal accumulation and release of radioactive iodine have been measured in each of the subjects of both groups before and after 1 month of their respective exercises at SL. One month of yogic exercises at SL has been observed to cause a significant reduction in the trans-thy-roidal availability of radioiodine. The thyroid radioactivity in this group of subjects was always below normal levels with the exception of two peaks of radioactive iodine uptake, when the levels of radioactivity in the thyroid were similar to the control values of pre-yogic exercises. The release of radiolabel at 24–48 h was significantly increased after yogic exercises. In contrast, the subjects performing PT exercises for the same duration at SL showed significant thyroid uptake of radioactive iodine at 24 h. Subsequently their131I uptake continued to rise slowly until 72 h without any demonstrable thyroidal release of radiolabel. This indicated that increased thyroid activity was induced by conventional PT exercise. Exposure of SL residents to HA irrespective of their exercise regime altered the thyroidal handling of radioiodine. Thyroidal concentrations of freshly administered radioiodine at early and late sampling intervals were very high in both of the groups, especially the yogics, after their return to SL from HA. Possible mechanisms of the observed changes have been discussed.  相似文献   
58.
Patterns of tree species distribution and their structural-functional features were studied along an altitudinal gradient in the Indian Central Himalaya. The forest vegetation falls within three formation types: low to mid-montane sclerophyllous, broad-leaved forests; mid-montane deciduous forests; and high-montane mixed stunted forests. Deciduous tree species formed a considerable (49%) portion of the high altitude forests between 1500–3300 m. The upper limit of forests ranges from 3000 to 3300 m, and three taxa are commonly found at tree line: an evergreen, needle-leaved gymnosperm (Abies pindrow Spach.), an evergreen, broad-leaved sclerophyllous oak (Quercus semecarpifolia Sm.), and a deciduous, broad-leaved birch (Betula utilis Don).The high altitude forests differed from the low altitude forests of Central Himalaya in their greater proportion of microphanerophytes. Vernal flowering is common at this elevation in Central Himalaya. In general, in their elevational distribution and structural-functional attributes, these high altitude forests are similar to other forests of cool temperate zones in Himalaya.  相似文献   
59.
Enantiomerically pure cyclopentyl cytosine [(?)-carbodine 1] was synthesized from d-ribose and evaluated for its anti-influenza activity in vitro in comparison to the (+)-carbodine, (±)-carbodine and ribavirin. (?)-Carbodine 1 exhibited potent antiviral activity against various strains of influenza A and B viruses.  相似文献   
60.
Molecular interactions between mesenchymal-derived Keratinocyte growth factor (KGF) and Kit ligand (KITLG) are essential for follicular development. These factors are expressed by theca and granulosa cells. We determined full length coding sequence of buffalo KGF and KITLG proteins having 194 and 274 amino acids, respectively. The recombinant KGF and KITLG proteins were solubilized in 10 mM Tris, pH 7.5 and 50 mM Tris, pH 7.4 and purified using Ni-NTA column and GST affinity chromatography, respectively. The purity and molecular weight of His-KGF (~23 kDa) and GST-KITLG (~57 kDa) proteins were confirmed by SDS-PAGE and western blotting. The co-immunoprecipitation assay accompanied with computational analysis demonstrated the interaction between KGF and KITLG proteins. We deduced 3D structures of the candidate proteins and assessed their binding based on protein docking. In the process, KGF specific residues, Lys123, Glu135, Lys140, Lys155 and Trp156 and KITLG specific ones, Ser226, Phe233, Gly234, Ala235, Phe236, Trp238 and Lys239 involved in the formation of KGF-KITLG complex were detected. The hydrophobic interactions surrounding KGF-KITLG complex affirmed their binding affinity and stability to the interacting interface. Additionally, in-silico site directed mutagenesis enabled the assessment of changes that occurred in the binding energies of mutated KGF-KITLG protein complex. Our results demonstrate that in the presence of KITLG, KGF mimics its native binding mode suggesting all the KGF residues are specific to their binding complex. This study provides an insight on the critical amino acid residues participating in buffalo ovarian folliculogenesis.  相似文献   
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