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681.
Saline soils are the major problem of cultivated lands of Iran. Suaeda aegyptiaca is a salt-tolerant plant (halophytes) that grow naturally in salt-affected areas of Iran. We have employed proteomics to identify the mechanisms of salt responsiveness in leaves of S. aegyptiaca grown under different salt concentrations. Ten-day-old plants were treated with 0, 150, 300, 450, and 600 mM NaCl. After 30 days of treatment, leaf samples were collected and analyzed using 2-D-PAGE. Out of 700 protein spots reproducible detected within replications, 102 spots showed significant response to salt treatment compared to 0 mM NaCl. We analyzed expression pattern of salt-responsive proteins using a hierarchical and two nonhierarchical (Fuzzy ART and SOM) statistical methods and concluded that Fuzzy ART is the superior method. Forty proteins of 12 different expression groups were analyzed using LC/MS/MS. Of these, 27 protein spots were identified including proteins involved in oxidative stress tolerance, glycinebetain synthesis, cytoskeleton remodeling, photosynthesis, ATP production, protein degradation, cyanide detoxification, and chaperone activities. The expression pattern of these proteins and their possible roles in the adaptation of S. aegyptiaca to salinity is discussed.  相似文献   
682.

Background

Spontaneous urticaria is a common allergic skin condition affecting 0.5–1% of individuals and may burden on health care expenditure or may be associated with remarkable morbidity.

Aim

In this study, we measured the effect of vitamin D supplementation in patients with a diagnosis of CSU. Furthermore, quality of life and cytokine changes were evaluated.

Methods

The clinical trial was conducted on 20 patients with idiopathic chronic urticaria. Vitamin D was administered orally for 8 weeks and disease activity was measured pre- and post-treatment using USS and DLQI. On the other hand expressions of IL-17, IL-10, Foxp3, and TGF-β by Real-time RT-PCR were assessed.

Results

USS questionnaire showed that severity of idiopathic urticaria after the intervention, which compared with the first day reached a significant 55% reduction. The DLQI quality of life questionnaire 2 months after treatment showed 55% improvement. Along with the significant improvement of clinical symptoms, use of vitamin D increase FOXP3 gene expression and downregulation of IL-10, TGF-B, and FOXP3, IL-17, but these changes were not statistically significant.

Limitation

These might happen due to lack of enrolled population in the investigation.

Conclusion

Vitamin D can be used along with standard medical care and it’s a safe and cost-effective method for the treatment of chronic urticaria with deficiency of vitamin D.
  相似文献   
683.
Resveratrol is a polyphenolic compound produced in very low levels in grapes. To achieve high yield of resveratrol in wild grape, three Agrobacterium rhizogenes strains, Ar318, ArA4 and LBA9402, were used to induce hairy roots following infection of internodes, nodes or petioles of in vitro grown Vitis vinifera subsp. sylvesteris accessions W2 and W16, and cultivar Rasha. The effects of inoculation time, age of explants, bacterial concentration and co-cultivation times were examined on the efficiency of the production of hairy roots. Strains Ar318, ArA4 and LBA9402 all induced hairy roots in the tested genotypes, but the efficiency of ArA4 strain was higher than the other strains. The highest hairy root production was with using internodes as explants. The transformation of hairy roots lines was confirmed by PCR detection of rolB gene. Half Murashige and Skoog (MS) medium was better for biomass production compared with MS medium. HPLC analysis of resveratrol production in the hairy root cultures showed that all the genotypes produced higher amounts of resveratrol than control roots. The highest amount of resveratrol was produced from W16 internode cultures, which was 31-fold higher than that of control root. Furthermore, TLC analysis showed that treatments of hairy roots with sodium acetate and jasmonate elevated resveratrol levels both in hairy root tissue and excreted into the half MS medium. These results demonstrate that endogenous and exogenous factors can affect resveratrol production in hairy root culture of grape, and this strategy could be used to increase low resveratrol production in grapes.  相似文献   
684.
Context: Ginsenoside Rb1 improves insulin sensitivity and glucose uptake in muscle cells via different signaling pathways; however, it is not clear that it has any effect on leptin signaling in skeletal muscle.

Objectives: The aim of this study was to investigate the effect of ginsenoside Rb1 on leptin receptors expression and main signaling pathways of leptin (STAT3, PI3 kinase and ERK kinase) in C2C12 skeletal muscle cells.

Materials and methods: C2C12 myotubes were incubated with various concentrations of Rb1 (0.1, 1 and 10?μM) for different incubation times (1–12?h). Leptin receptors expression and GLUT-4 translocation were analyzed using realtime PCR and western blot analyses, respectively. PI3 and ERK kinases were blocked using their specific inhibitors (wortmannin and PD98059) in the presence and absence of RB1 to determine the main signaling pathway related to leptin receptor activation in C2C12 cells.

Results: Rb1 could maximally stimulate both leptin receptors (OBRa and OBRb) mRNA and protein expression and phosphorylation of STAT3, PI3K and ERK2 in C2C12 myotubes at 10?μM for 3?h. Rb1 induced GLUT4 translocation was inhibited by the silencing of OBRb mRNA, demonstrated that glucose uptake was mediated via leptin receptor activation. GLUT4 recruitment to the cell surface induced by Rb1 was inhibited by wortmannin, an inhibitor of PI3K in combination with OBRb siRNA, but not by PD98059 an ERK2 kinase-1 inhibitor, indicating that GLUT4 translocation induced by Rb1 was associated with the leptin receptor upregulation and subsequent activation of PI3K.

Conclusions: Our results suggest that Rb1 promote translocation of GLUT4 by upregulation of leptin receptors and activation of PI3K.  相似文献   
685.
It was found that using chelating agents increases the efficiency of heavy metal extraction, however, they may have negative effects on soil ecosystem quality. A pot experiment was conducted in a completely randomized design with three replications in order to evaluate the effect of EDTA and Olive Husk Extract (OHE) on some chemical and biological properties of the Pb-contaminated soil. The experimental treatments included EDTA (2 g Na2EDTA salt per kg soil), OHE (2 g TDS of OHE per kg soil) and control (without the chelating agent). The results revealed that the EDTA and OHE treatments increased the Pb availability by 17.7% and 5.5% in comparison to the control treatment, respectively. Although EDTA was more effective in increasing the Pb availability but decreased the soil biological quality index (SBQI). The EDTA treatment significantly decreased the dehydrogenase (DH) activity and germination index (GI). The OHE application significantly increased the available-P, available-K, total N and organic carbon content by 339.92%, 40.79%, 20.9%, and 29.7% compared with control treatment, respectively. Furthermore, OHE considerably increased SBQI from 18.96 to 53.48. Compared to the control treatment higher values of soil respiration activity, DH activity, and carbon availability index (CAI) were observed in OHE treatment.  相似文献   
686.
As the theoretical limit of intercalation material‐based lithium‐ion batteries is approached, alternative chemistries based on conversion reactions are presently considered. The conversion of sulfur is particularly appealing as it is associated with a theoretical gravimetric energy density up to 2510 Wh kg?1. In this paper, three different carbon‐iron disulfide‐sulfur (C‐FeS2‐S) composites are proposed as alternative positive electrode materials for all‐solid‐state lithium‐sulfur batteries. These are synthesized through a facile, low‐cost, single‐step ball‐milling procedure. It is found that the crystalline structure (evaluated by X‐ray diffraction) and the morphology of the composites (evaluated by scanning electron microscopy) are greatly influenced by the FeS2:S ratio. Li/LiI‐Li3PS4/C‐FeS2‐S solid‐state cells are tested under galvanostatic conditions, while differential capacity plots are used to discuss the peculiar electrochemical features of these novel materials. These cells deliver capacities as high as 1200 mAh g(FeS2+S)?1 at the intermediate loading of 1 mg cm?2 (1.2 mAh cm?2), and up to 3.55 mAh cm?2 for active material loadings as high as 5 mg cm?2 at 20 °C. Such an excellent performance, rarely reported for (sulfur/metal sulfide)‐based, all solid‐state cells, makes these composites highly promising for real application where high positive electrode loadings are required.  相似文献   
687.
688.
Heavy metal contaminations in the environment of mining area have become a global problem. The vicinity of an iron ore mine was investigated to estimate the concentrations of As, Pb, Cd, Mn, Ni, Zn, and Cr in the soil and the feasibility of using native plants for phytoremediation. For this, concentrations of elements in soil samples collected and were analyzed by inductivity coupled plasma optical emission spectrometry. The concentrations of heavy metals and arsenic in the roots and aerial parts of Dactylis glomerata L. and Scleranthus orientalis Rössler were analyzed by inductively coupled plasma mass spectrometer too. As concentrations in the samples surpassed the soil toxicity threshold. Cd concentration in soil samples was considerably high next to mine pit. Neither species was identified as a hyperaccumulator, but both species could be considered as excluder plants for As.  相似文献   
689.
Breast cancer (BC) is one of the most common causes of death among women, and second in Iran. The objectives of this study were to determine the frequency of RAD51 G/C polymorphism in patients with breast cancer. We evaluated these polymorphisms and effects on the breast cancer risk association in a Iranian sporadic population-based case?Ccontrol study of 294 breast cancer cases and 315 controls using a PCR?CRFLP-based assay. Analyses of affected and controls show that homozygote genotype RAD51 GG has the highest frequency in both groups (33.3 in patients and 41.4 in control group). Genotype RAD51 GG most risk factor were in our population: [CC/GC odds ratio, 0.364 (95?% confidence interval; CI, 0.168?C0.788) p?=?0.009, CC/GG odds ratio, 0.828 (95?% CI, 0.411?C1.668) p?=?0.596], GG/GC odds ratio, 2.276 (95?% CI, 1.497?C3.460) p?=?0.001]. There was a significant association of breast cancer risk with RAD51 GG and CC polymorphism.  相似文献   
690.
Spermatogonial stem cells are unique cells of testes that can restore fertility upon transplantation into recipient testes. However, use of suitable markers for enrichment of these cells have important potential application. THY1, is an established conserved marker of spermatogonial stem cells in bovine, rodents, and primates, but there is no information available in goats. After three rounds of enzymatic digestion of prepubertal goat testicular tissues, undifferentiated spermatogonia positive for THY1 were isolated by magnetic-activated cell sorting and were used for immunocytochemistry, real-time polymerase chain reaction analysis for gene expression, protein expression, and transplantation into recipient mice. Immunocytochemical analyses showed that significantly higher percentage of THY1+ cells were positive for PLZF and VASA when compared with unselected population. This result for PLZF was further confirmed at the protein level. Real-time polymerase chain reaction analysis revealed that expression of THY1, PLZF, VASA, BCL6B, and UCHL1 as SCCs characteristic genes in THY1+ cells was significantly higher than in the initial population. Finally, transplantation of PKH26-labeled cells revealed that THY1+ cells had higher capacity for colony formation when compared with unselected cells. In conclusion, the results provide indications that THY1 surface marker can be reliably used for enrichment of undifferentiated spermatogonial in the goats.  相似文献   
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