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211.
It has been suggested that cyclooxygenase-2 (COX-2)-mediated prostaglandin synthesis is associated with liver inflammation and carcinogenesis. The aim of this study is to identify the cellular source of COX-2 expression in different stages, from acute liver injury through liver fibrosis to cholangiocarcinoma (CC). We induced in rats acute and “chronic” liver injury (thioacetamide (TAA) or carbon tetrachloride (CCl4)) and CC development (TAA) and assessed COX-2 gene expression in normal and damaged liver tissue by RT-PCR of total RNA. The cellular localization of COX-2 protein in liver tissue was analyzed by immunohistochemistry as well as in isolated rat liver cells by Western blotting. The findings were compared with those obtained in human cirrhotic liver tissue. The specificity of the antibodies was tested by 2-DE Western blot and mass spectrometric identification of the positive protein spots. RT-PCR analysis of total RNA revealed an increase of hepatic COX-2 gene expression in acutely as well as “chronically” damaged liver. COX-2-protein was detected in those ED1+/ED2+ cells located in the non-damaged tissue (resident tissue macrophages). In addition COX-2 positivity in inflammatory mononuclear phagocytes (ED1+/ED2), which were also present within the tumoral tissue was detected. COX-2 protein was clearly detectable in isolated Kupffer cells as well as (at lower level) in isolated “inflammatory” macrophages. Similar results were obtained in human cirrhotic liver. COX-2 protein is constitutively detectable in liver tissue macrophages. Inflammatory mononuclear phagocytes contribute to the increase of COX-2 gene expression in acute and chronic liver damage induced by different toxins and in the CC microenvironment.  相似文献   
212.
International Journal of Peptide Research and Therapeutics - Zinc oxide may influence central nervous system development in offspring but there is no information on role of the zinc oxide...  相似文献   
213.

Hydrogen sulfide (H2S) has emerged as a novel gaseous signal molecule with multifarious effects on seed germination, plant growth, development, and physiological processes. Due to its dominant role in plant stress tolerance and cross-adaptation, it is getting more attention nowadays, although it has been largely referred as toxic and environmental hazardous gas. In this review work, we are highlighting the importance of H2S as an essential gaseous molecule to help in signaling, metabolism, and stress tolerance in plants. Firstly, production of H2S from different natural and artificial sources were discussed with its transformation from sulfur (S) to sulfate (SO42−) and then to sulfite (SO32−). The importance of different kinds of transporters that helps to take SO42− from the soil solution was presented. Mainly, these transporters are SULTRs (H+/SO42− cotransporters) and multigene family encodes them. Furthermore, these SULTRs have LAST (Low affinity transport proteins), HAST (High affinity transport proteins), vacuole transporters, and plastid transporters. Since it is well known that there is strong relationship between SO42− and synthesis of hydrogen sulfide or dihydrogen sulfide or sulfane in plant cells. Thus, cysteine (Cys) metabolism through which H2S could be generated in plant cell with the role of different enzymes has been presented. Furthermore, H2S in interaction with other molecules could help to mitigate biotic and abiotic stress. Based on this review work, it can be concluded that H2S has potential to induce cross-adaptation to biotic and abiotic stress; thus, it is recommended that it should be considered in future studies to answer the questions like what are the receptors of H2S in plant cell, where in plants the physiological concentration of H2S is high in response to multiple stress and how it induces cross-adaptation by interaction with other signal molecules.

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214.
In the current study, we investigated the phytochemical and neuropharmacological potential of Indigofera sessiliflora, an indigenous least characterized plant widely distributed in deserted areas of Pakistan. The crude extract of the whole plant Indigofera sessiliflora (IS.CR) was preliminary tested in-vitro for the existence of polyphenol content, antioxidant and anticholinesterase potential followed by detailed chemical characterization through UHPLC-MS. Rats administered with different doses of IS.CR (100–300 mg/kg) for the duration of 4-weeks were behaviorally tested for anxiety and cognition followed by biochemical evaluation of dissected brain. The in-silico studies were employed to predict the blood–brain barrier crossing tendencies of secondary metabolites with the elucidation of the target binding site. The in-vitro assays revealed ample phenols and flavonoids content in IS.CR with adequate anti-oxidant and anticholinesterase potential. The dose-dependent anxiolytic potential of IS.CR was demonstrated in open field (OFT), light/dark (L/D) and elevated plus maze (EPM) tests as animals spent more time in open, illuminated and elevated zones (P < 0.05). In the behavioral tests for learning/memory, the IS.CR reversed the scopolamine-induced cognitive deficits, as animals showed better (P < 0.05) spontaneous alternation and discrimination index in y-maze and novel object recognition (NOR) tests. Similarly, as compared to amnesic rats, the step-through latencies were increased (P < 0.05) and escape latencies were decreased (P < 0.05) in passive avoidance (PAT) and Morris water maze (MWM) tests, respectively. Biochemical analysis of rat brains showed significant reduction in malondialdehyde and acetylcholinesterase levels, alongwith preservation of glutathione peroxidase and superoxide dismutase activity. The docking studies further portrayed a possible interaction of detected phytoconstituents with acetylcholinesterase target. The results of the study show valuable therapeutic potential of phytoconstituents present in IS.CR to correct the neurological disarrays which might be through antioxidant activity or via modulation of GABAergic and cholinergic systems by artocommunol, 1,9-dideoxyforskolin and 6E,9E-octadecadienoic acid.  相似文献   
215.
Effect of growing seedling, seeds and seedlings extracts from seven leguminous plants (Pisum sativum, Vigna radiata, Vigna mungo, Cajanus cajan, Lentil culinaris, Cicer arietinum and Trigonella foenum graecum) were screened for their ability to influence quorum sensing controlled pigment production in Chromobacterium violaceum indicator strains (CV12472 and CVO26). Germinating seedling and seedling extracts of only P. sativum (pea) showed inhibition of violacein production. Interestingly, the T. foenum graecum (fenugreek) seed extracts enhances the pigment production. Quorum sensing regulated swarming motility in Pseudomonas aerugionsa PAO1 was reduced by pea seedling extract while enhanced by the fenugreek seed extracts. These findings suggest that plant metabolites of some legumes interact actively with bacterial quorum sensing and could modulate its associated functions.  相似文献   
216.
甲醛诱导Tau蛋白形成“孔道样”聚集结构   总被引:2,自引:1,他引:2  
尽管Lin等(University of California, Santa Barbara)就蛋白构象病中细胞死亡的机制提出了“非特异性淀粉样离子通道”(aspecific amyloid ion channels)学说,但到目前为止,尚未发现神经Tau蛋白能形成“孔道样”聚集结构,也未寻找到可以导致蛋白质形成“孔道样”聚集结构的诱导剂.依据本实验室提出的“散发性老年痴呆发生发展中的内源性甲醛慢性损伤”假说,采用一定浓度的甲醛与Tau蛋白进行温育,观察到甲醛可以明显诱导Tau蛋白分子聚集并形成淀粉样沉积物,同时也观察到了Tau蛋白“孔道样”聚集结构.上述结果为探索甲醛诱导Tau蛋白错误折叠形成的产物导致细胞代谢障碍和死亡的机制提供了新的研究思路.  相似文献   
217.
A technique is described for simple flow assessment of the in situ radial artery conduit during coronary bypass via a small incision. This technique allows morphologic and physiologic direct intraoperative assessment of radial artery quality and expands the use of radial artery during coronary artery surgery.  相似文献   
218.

Salinity restricts plant growth and production by specific ions toxicity to particular plants. Cl ion is exceptionally toxic to citrus. Citrus rootstock and scion has a significant effect on each other under unfavourable conditions. Nevertheless, their specific response can be different depending on the way to translocate and compartment the toxic ions, or to induce antioxidant systems. In this paper, we studied the behaviour of diploid (2x) and tetraploid (4x) Volkamer lemon rootstocks grafted with commercial cultivar Kinnow mandarin (KM/VM2x and KM/VM4x, respectively) when exposed to moderate (75 mM) and high salt stress (150 mM). Both genotypes showed a decrease in their photosynthetic variables (Pn, gs, E, Fv/Fm, Fv′/Fm′, NPQ), and the decline was more significant in KM/VM2x plants as compared to KM/VM4x. The highest increase in the concentration of stress indicators (MDA and H2O2) was observed in leaves and roots of KM/VM2x at 75 and 150 mM of salt stress. The KM/VM4× showed the maximum increase in antioxidative enzymes (SOD, CAT, POD, APx, GR) and osmolytes (PRO, GB) in leaves and roots at 75 and 150 mM. Minerals (Cl ion, Na, K, P, N, Ca) accumulation was also significantly affected in leaves and roots of KM/VM2x and KM/VM4x under moderate and high NaCl stress. Overall, our results showed that Cl ion accumulation presents a robust correlation with stress indicators and their scavenging enzymes in leaves and roots. Moreover, 2x scion significantly mitigated by the 4x rootstock and showed more tolerance as compared to grafted on 2x rootstock.

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219.
Liu N  Xu Y  Hossain S  Huang N  Coursolle D  Gralnick JA  Boon EM 《Biochemistry》2012,51(10):2087-2099
Although several reports have documented nitric oxide (NO) regulation of biofilm formation, the molecular basis of this phenomenon is unknown. In many bacteria, an H-NOX (heme-nitric oxide/oxygen-binding) gene is found near a diguanylate cyclase (DGC) gene. H-NOX domains are conserved hemoproteins that are known NO sensors. It is widely recognized that cyclic di-GMP (c-di-GMP) is a ubiquitous bacterial signaling molecule that regulates the transition between motility and biofilm. Therefore, NO may influence biofilm formation through H-NOX regulation of DGC, thus providing a molecular-level explanation for NO regulation of biofilm formation. This work demonstrates that, indeed, NO-bound H-NOX negatively affects biofilm formation by directly regulating c-di-GMP turnover in Shewanella woodyi strain MS32. Exposure of wild-type S. woodyi to a nanomolar level of NO resulted in the formation of thinner biofilms, and less intracellular c-di-GMP, than in the absence of NO. Also, a mutant strain in the gene encoding SwH-NOX showed a decreased level of biofilm formation (and a decreased amount of intracellular c-di-GMP) with no change observed upon NO addition. Furthermore, using purified proteins, it was demonstrated that SwH-NOX and SwDGC are binding partners. SwDGC is a dual-functioning DGC; it has diguanylate cyclase and phosphodiesterase activities. These data indicate that NO-bound SwH-NOX enhances c-di-GMP degradation, but not synthesis, by SwDGC. These results support the biofilm growth data and indicate that S. woodyi senses nanomolar NO with an H-NOX domain and that SwH-NOX regulates SwDGC activity, resulting in a reduction in c-di-GMP concentration and a decreased level of biofilm growth in the presence of NO. These data provide a detailed molecular mechanism for NO regulation of c-di-GMP signaling and biofilm formation.  相似文献   
220.
Background:The association of 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) and its receptor, vitamin D receptor (VDR), with cancer types have been studied. However, there are controversial findings regarding the association of specific VDR polymorphisms with different kinds of cancers. In the current study, we investigated the association of VDR polymorphisms (Fok1 (rs2228570), ApaI (rs7975232), BsmI (rs1544410), and TaqI (rs731236)) with the risk of gastric cancer in a Kurdish population of Kermanshah in Iran for the first time. Methods:In this case-control study, the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used in 99 gastric cancer patients and 100 healthy subjects as controls.Results:The frequencies of f (FokI), b (BsmI), t (TaqI), and a (ApaI) alleles were: 55.6%, 27.3%, 62.1%, and 44.95% in the patient group, respectively and 42%, 29.5%, 54.5%, and 46.0% in the control group, respectively. Analysis of the results indicated that there was a positive association between the frequency of FokI genotypes with gastric cancer risk (p= 0.021). However, no statistically significant association of BsmI, Taq1, and ApaI polymorphisms of VDR was detected in gastric patients when compared with healthy individuals.Conclusion:VDR-FokI polymorphism could increase the risk of GC development and predispose to the disease by mechanisms.Key Words: Gastric cancer, PCR-RFLP, Polymorphism, Vitamin D receptor  相似文献   
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