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361.
362.
Iness Bettaieb Ibtissem Hamrouni-Sellami Soumaya Bourgou Ferid Limam Brahim Marzouk 《Acta Physiologiae Plantarum》2011,33(4):1103-1111
Salvia officinalis L. is a medicinal plant containing several compounds with important pharmacological activity. In this study, we investigated
the effects of water deficit (moderate and severe water deficits) on the contents of total and individual polyphenols of the
aerial parts. Also, we studied the effect of drought on the antioxidant activity of methanolic extracts. Our results showed
that water deficiency, as estimated by the decrease in water potential, resulted in a reduction of the biomass, plant height
and total chlorophyll contents. In general, drought increased the level of total and individual polyphenols and this increase
was more pronounced under moderate water deficit. These findings suggest that S. Officinalis is a sensitive species and that a severe water deficit could result in a decline in the activity of enzymes involved in the
biosynthesis of phenolic compounds. On the other hand, our results showed an enhancement of reducing power and the radical
scavenging activity as assessed using the DPPH assay with increasing stress severity. Finally, the evaluation of the chelating
capacity of the extracts was found to be altered significantly under severe treatment by 39.71%. Based on these results, it
seems that drought tolerance of S. officinalis is related to the capacity of the plant to modulate its phenolics in order to face to oxidative stress caused by water limiting
conditions. 相似文献
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Daniel Nouri-Nejad Brooke L. ODonnell Chetan S. Patil Rafael E. Sanchez-Pupo Danielle Johnston Samar Sayedyahossein Kristina Jurcic Rebecca Lau Laszlo Gyenis David W. Litchfield Michael F. Jackson Gregory B. Gloor Silvia Penuela 《Molecular biology of the cell》2021,32(5):376
Pannexin 1 (PANX1) is a glycoprotein that forms large pore channels capable of passing ions and metabolites such as ATP for cellular communication. PANX1 has been implicated in many diseases including breast cancer and melanoma, where inhibition or deletion of PANX1 reduced the tumorigenic and metastatic properties of the cancer cells. We interrogated the effect of single amino acid changes in various PANX1 domains using naturally occurring variants reported in cancer patient tumors. We found that a previously reported variant (Q5H) is present in cancer cells, but was not different from the wild type (Q5) in glycosylation, trafficking, or channel function and did not affect cellular properties. We discovered that the Q5H variant is in fact the highly conserved ancestral allele of PANX1 with 89% of humans carrying at least one Q5H allele. Another mutated form Y150F, found in a melanoma patient tumor, prevented phosphorylation at Y150 as well as complex N-glycosylation while increasing intracellular localization. Sarcoma (SRC) is the predicted kinase to phosphorylate the Y150 residue, and its phosphorylation is not likely to be constitutive, but rather dynamically regulated. The Y150 phosphorylation site is the first one reported to play a role in regulating posttranslational modifications and trafficking of PANX1, with potential consequences on its large-pore channel structure and function in melanoma cells. 相似文献
366.
Gangliosides and neutral glycolipids of muscles from normal and dystrophic chickens were studied. Total glycolipid content of the degenerating muscles was higher than the normal muscles. In addition, the myopathic muscles contained a ganglioside which was absent in the unaffected muscles from normal and dystrophic chickens. Based on the thin-layer chromatographic mobility, treatment with neuraminidases from Vibrio cholerae and Arthrobacter ureafaciens, and reactivity of the asialo-derivative towards anti-ganglio-N-triaosylceramide antibody, the dystrophic-specific ganglioside was tentatively identified as GM2. Data obtained from young and old dystrophic chickens suggested a direct relationship of this ganglioside to muscular dystrophy. 相似文献
367.
The aim of the present study was to investigate the protective role of grape seed extract (containing proanthocyandin) against the adverse effects of plant growth regulators (GA3 (gibberellic acid) and IAA (indoleacetic acid)). The present data showed that the administration of either GA3 and IAA caused undesirable changes in both hepatic and testicular structure. This was evidenced by a disturbed hepatic strands, pyknotic nuclei, central vein with collapsed endothelium, dilatation in bile sinusoids, congested blood vessel, binucleatd hepatocytes, lymphocytic infiltration, vacuolation, giant hepatic cells, increased Kupffer cells and karyoryxis. Additionally, it was shown that degenerative changes in the testis, spermatogenic arrest, moderate tubular necrosis, Leydig cell degeneration and reduction in the number and size of the seminiferous tubules with some spermatogonia detached from the basement membrane. Concerning flow cytometric study of the liver a significant decrease in G0/1 % and a significant increase in S phase %, G2/M %, P53 % and apoptosis % (sub G1) were detected. However, in testis the data recorded a significant decrease in the percentage of mature sperm (percentage of haploid cells) and a significant increase in the percentage of spermatide, diploid cells, P53 and of apoptotic cells. On the other hand, a distinct recovery of the mentioned hepatic and testicular histopathological and cytogenetic disorders was observed when proanthocyanidin was supplemented to rats administered either of the plant growth hormones (GA3 and IAA). 相似文献
368.
Remediation was successfully completed in a petroleum-contaminated site using ozone sparging combined with soil vapor extraction technologies. The site contained high levels of BTEX contamination in dissolved, adsorbed, and free phases. The presence of fine-grained soil, smear zone contamination, and shallow groundwater posed challenging site conditions for this remediation. Active remediation was performed for approximately 18 months followed by one year of post-remediation monitoring. Application of soil vapor extraction technology effectively removed free phase contamination. Biodegradation during active and post-remediation periods also played a role in bringing down the contaminant levels and achieving closure of the release. The cost of this remediation approach was estimated to be $2.04 per cubic foot ($72.08 per cubic meter) and found to be cost-effective. Timely completion of the project prevented the spreading of contaminants towards the down-gradient residential and school properties. 相似文献