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151.
Ihsan Elahi Zaheer Shafaqat Ali Muhammad Hamzah Saleem Mohsin Ali Muhammad Riaz Sehar Javed Anam Sehar Zohaib Abbas Muhammad Rizwan Mohamed A. El-Sheikh Mohammed Nasser Alyemeni 《Physiology and Molecular Biology of Plants》2020,26(12):2435
AbstractUntreated wastewater contains toxic amounts of heavy metals such as chromium (Cr), which poses a serious threat to the growth and physiology of plants when used in irrigation. Though, Cr is among the most widespread toxic trace elements found in agricultural soils due to various anthropogenic activities. To explore the interactive effects of micronutrients with amino acid chelators [iron-lysine (Fe-lys) and zinc-lysine (Zn-lys)], pot experiments were conducted in a controlled environment, using spinach (Spinacia oleracea L.) plant irrigated with tannery wastewater. S. oleracea was treated without Fe and Zn-lys (0 mg/L Zn-lys and 0 mg/L Fe-lys) and also treated with various combinations of (interactive application) Fe and Zn-lys (10 mg/L Zn-lys and 5 mg/L Fe-lys), when cultivated at different levels [0 (control) 33, 66 and 100%) of tannery wastewater in the soil having a toxic level of Cr in it. According to the results, we have found that, high concentration of Cr in the soil significantly (P < 0.05) reduced plant height, fresh biomass of roots and leaves, dry biomass of roots and leaves, root length, number of leaves, leaf area, total chlorophyll contents, carotenoid contents, transpiration rate (E), stomatal conductance (gs), net photosynthesis (PN), and water use efficiency (WUE) and the contents of Zn and Fe in the plant organs without foliar application of Zn and Fe-lys. Moreover, phytotoxicity of Cr increased malondialdehyde (MDA) contents in the plant organs (roots and leaves), which induced oxidative damage in S. oleracea manifested by the contents of hydrogen peroxide (H2O2) and membrane leakage. The negative effects of Cr toxicity could be overturned by Zn and Fe-lys application, which significantly (P < 0.05) increase plant growth, biomass, chlorophyll content, and gaseous exchange attributes by reducing oxidative stress (H2O2, MDA, EL) and increasing the activities of various antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD) catalase (CAT) and ascorbate peroxidase (APX). Furthermore, the supplementation of Zn and Fe-lys increased the contents of essential nutrients (Fe and Zn) and decreased the content of Cr in all plant parts compared to the plants cultivated in tannery wastewater without application of Fe-lys. Taken together, foliar supplementation of Zn and Fe-lys alleviates Cr toxicity in S. oleracea by increased morpho-physiological attributes of the plants, decreased Cr contents and increased micronutrients uptake by the soil, and can be an effective in heavy metal toxicity remedial approach for other crops.Graphic abstract 相似文献
152.
The effects of a constant infusion of insulin (12 mu/kg·min for 90 min) on glucose turnover (determined by means of the primed-constant infusion of 6-3H-glucose) was evaluated in normal and burned (50% BSA) guinea pigs (gp). In burned, untreated gp, the mean plasma glucose level (gl) was increased from 129±8.2 to 205±13.7 mg/dl 90 min after burning, whereas gl was 140±14.5 mg/dl in the burned + insulin-infused animals at 90 min. The insulin infusion reduced gl from 120±5.6 to 69±5.8 mg/dl in unburned gp; the rate of glucose appearance (Ra) was reduced and the metabolic clearance rate (MCR) was increased. In the B+I gp, the insulin effectively minimized the increase in Ra which followed burning in the burned, untreated gp. However, insulin did not increase the MCR of the burned + insulin-infused group above that of the burned, untreated group. On the day following the burn, the insulin infusion decreased gl in the burned gp to the same extent as in the unburned animals and also increased MCR. We concluded that whereas there was a lack of peripheral responsiveness to the insulin infusion in the first 90 min after burning (during the shock phase), no such lack of responsiveness was evident on the second day. 相似文献
153.
Developing taste buds in the anterior mandibular floor of perihatching
chicks were studied by high voltage electron microscopic autoradiography in
order to identify proliferating gemmal cell types. Montaged profiles of 29
taste buds in five cases euthanized between embryonic day 21 and
posthatching day 2 were analyzed after a single [3H]thymidine injection
administered on embryonic day 16, 17 or 18. Results showed that dark cells
comprised 55% of identified (n = 900 cells) and 62% of labeled (n = 568
cells) gemmal cells as compared with light, intermediate, basal or
perigemmal bud cells. Dark cells had both a greater (P < 0.05) number of
labeled cells and a greater amount of label (grains/nucleus) than the other
four bud cell types, irrespective of injection day. The nuclear area
(micron 2) of dark cells was not significantly larger (P > 0.05) than
that of the other gemmal cell types and therefore cannot account for the
greater amount for label in the dark cells. Interestingly, only dark cells
showed a positive correlation (P < 0.003) between amount of label and
nuclear area. Results suggest that, during the perihatching period of
robust cell proliferation, dividing dark cells may give rise primarily, but
not exclusively, to dark cell progeny.
相似文献
154.
The major rivers of the South African ‘Lowveld’ (low-latitude savanna) suffer numerous impacts from upstream economic activities. Whereas monitoring these rivers is required to detect biodiversity losses, record pollution events and devise mitigation strategies, current monitoring programmes are inadequate. In 2009, the South African Earth Observation Network initiated an intensive long-term research programme on the Lowveld reaches of the Olifants River. Physico-chemical parameters, aquatic macroinvertebrates and fish abundances were recorded at four Lowveld sites in the Olifants River. We review six years of this programme. The results suggest deterioration in the ecological condition of the Olifants River with no discernible improvement through protected areas. Trends could not be detected. The parameters measured, sampling methods and/or sampling frequency might be responsible for the limited trends observed, or alternatively the results simply reflect stable conditions despite on-going pollution. Real time monitoring and an expansion in the parameters monitored would add value to the monitoring programme. 相似文献
155.
The postnatal methylation of transfer ribonucleic acid in brain. Evidence for the methylation of precursor transfer ribonucleic acid. 下载免费PDF全文
Incubation of 3-day-old rat brain with L-[methyl-3H]methionine resulted in the rapid labeling of low-molecular-weight cytoplasmic RNA. Electrophoresis in 15% polyacrylamide gels provided evidence for the methylation of precursor tRNA molecules, and high-performance liquid chromatography demonstrated N2-methylguanine to be the predominant methylated base formed during the first 2 min of labelling. 相似文献