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161.
162.
Environmental factors–ecological species group relationships in the Surash lowland‐mountain forests in northern Iran
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Fatemeh Bazdid Vahdati Shahryar Saeidi Mehrvarz Daniel C. Dey Alireza Naqinezhad 《Nordic Journal of Botany》2017,35(2):240-250
Identification of the primary factors that influence the ecological distribution of species groups is important to managers of lowland‐mountain forests in northern Iran. The aim of this study was to identify main ecological species groups, describe the site conditions associated with these species groups and the relationships between environmental factors and the distribution of ecological species groups using multi‐variate analysis (Detrended correspondence analysis (DCA) and Canonical correspondence analysis (CCA)). For this purpose, 50 relevés (400 m2 each) were sampled using the Braun‐Blanquet method. Vegetation was classified into three ecological species groups using a modified two‐way indicator species analysis (TWINSPAN). In each relevé, environmental factors (topographic and soil variables) were measured and analysed using one‐way ANOVA and Pearson r statistics. Further, species diversity indices were determined for the identified ecological species groups. Our results show that the environmental factors, e.g. elevation, slope, slope aspect, soil texture, pH and organic matter, were the most important factors explaining the distribution of the three ecological species groups in the study area. The diversity of the ecological species groups decreased with elevation. The results provide an ecological basis for forest management and for developing strategies for forest conservation in the study area. 相似文献
163.
Mahmoud Mehranian Reza Farshbaf Pourabad Nemat Sokhandan Bashir Alireza Motavalizadehkakhky 《Archives Of Phytopathology And Plant Protection》2017,50(1-2):47-61
Cuticular analysis of Ephestia kuehniella females by gas chromatography-mass spectrometry revealed the presence of four groups of chemical compounds including alkane, alcohol, aldehyde and fatty acid. The cuticular n-alkanes ranged from 12 to 18, 20, 23, 24 and 29 carbon atoms in the chain. The most abundant n-alkanes detected in the cuticular extracts were C14 (14.98%) and C18 (8.15%). Cuticular fatty acids included hexadecenoic acid, 9-octadecenoic acid and 9,12-octadecenoic acid. Two types of alcohol including, 2-methyl-Z,Z-3,13-octadecadienol and 9-methyl-Z-10-tetradecen-1-ol acetate, were found in the cuticular lipids of the females. Two aldehyde components, (E)-11-hexadecenal and 9,17-octadecadienal, were identified in the cuticular extract of E. kuehniella. Antibacterial activity of the cuticular compounds was tested against Bacillus subtilis, Bacillus thuringiensis and Escherichia coli. These compounds from the moths inhibited the growth of Gram-positive bacteria. The functional characteristics of the cuticular compounds operating as pheromones, species-associated compounds and host-resistant compounds to bacterial infection are discussed. 相似文献
164.
Alireza Sharif Hamed Haddad Kashani Elahe Nasri Zahra Soleimani Mohammad Reza Sharif 《Probiotics and antimicrobial proteins》2017,9(4):380-385
Diarrhea is considered as an important cause of morbidity and mortality, even though one of the main reasons of death following diarrhea is initiated by dysentery. In recent years, the consumption of probiotics has been proposed for the treatment of infectious diarrhea. Despite most of the studies on probiotics have focused on acute watery diarrhea, few studies in the field of dysentery have found beneficial effects of probiotics. This study is a randomized double-blind clinical trial. The patients were randomly placed into control and case groups. In the intervention group, the patients received probiotics in the form of Kidilact® sachet, which contained high amounts of 7-strain friendly bacteria strains of Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Bifidobacterium infantis, Bifidobacterium breve, and Streptococcus thermophiles. On the other hand, the patients in the control group received placebo sachets on a daily basis for 5 days. It is notable that the treatment protocol of acute dysentery was done on both groups. The results of this study showed significant differences in the duration of blood in diarrhea between probiotic consumers (2.62 days) and the control group (3.16 days) (P value = 0.05). Additionally, significant differences in the average length of hospitalization in probiotic consumers (3.16 days) and control (3.66 days), (P value = 0.02) could be claimed that the consumption of probiotics is effective in reducing the duration of dysentery and diarrhea. The results of this study suggest that the use of probiotics can be effective in reducing the duration of blood in diarrhea. This study was also recorded in the Iran center of clinical trials registration database (IRCT2014060617985N1). 相似文献
165.
Heckl S Regenbogen M Sturzu A Gharabaghi A Feil G Beck A Echner H Nagele T 《Apoptosis : an international journal on programmed cell death》2008,13(4):495-508
Apoptin, a protein of the chicken anemia virus (CAV), consists of 121 amino acids (aa) and represents a novel, potentially
tumor-specific therapeutic and diagnostic agent. The C-terminal part of Apoptin (aa 81–121) is believed to contain a bipartite
nuclear localization signal (NLS) (NLS1: aa 82–88 and NLS2: aa 111–121), which is only active in tumor cells after phosphorylation
of threonine108 by tumor-specific cytoplasmic phosphokinases. Furthermore, a nuclear export signal (NES) (aa 97–105) seems to enable nuclear
export of Apoptin only in healthy cells. The specificity for tumor cell nuclei also applies to the truncated C-terminal part
of Apoptin (aa 81–121), which therefore represents a highly attractive peptide sequence for peptide synthesis. Here we describe
for the first time the synthesis of fluorescein isothiocyanate (FITC)- and Dansyl-labelled conjugates containing this C-terminal
part of Apoptin, with either phosphorylated or nonphosphorylated threonine108. The phosphorylated conjugates were synthesized in an attempt to achieve nuclear accumulation in healthy cells, which lack
cytoplasmic tumor-specific phosphokinases. Surprisingly, all the conjugates accumulated rapidly within the cell nuclei of
both tumor and non-tumor cells from the bladder, brain and prostate and led to cell death. By coupling Apoptin81–121 to FITC and DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) at either the C- or N-terminus we could exlude
that the coupling site is decisive for tumor cell-specific nuclear localization. The labels FITC, DOTA and Dansyl were not
responsible for cell death in healthy cells because cell death was not prevented by using an unlabelled Apoptin81–121 peptide. Cellular and nuclear uptake of the FITC-labelled Apoptin81–121 peptide was almost completely abolished after altering the NLS2 (replacement of five arginines with serines). 相似文献
166.
Emami S Foroumadi A Falahati M Lotfali E Rajabalian S Ebrahimi SA Farahyar S Shafiee A 《Bioorganic & medicinal chemistry letters》2008,18(1):141-146
2-Hydroxyphenacyl azole and 2-hydroxyphenacyl azolium compounds have been described as a new class of azole antifungals. Most target compounds showed significant in vitro antifungal activities against tested fungi (Candida albicans, Saccharomyces cerevisiae, Aspergillus niger, and Microsporum gypseum) with low MICs values included in the range of 0.25-32 microg/mL comparable to reference drug fluconazole. The most active compounds were also assessed for their cytotoxicity using MTT colorimetric assay on normal mouse fibroblast (NIH/3T3) cells. The results of antifungal activity and toxicity tests indicated that these compounds display antifungal activity at non-cytotoxic concentrations. 相似文献
167.
We have compared the gas phase thermochemical properties of aspartame (artificial sweetener) and α- and β-glucose. These parameters include metal ion affinities with Li+-, Na+-, K+-, Mg+2-, Ca+2-, Fe+2-, Zn+2-ions, and chloride ion affinity by using DFT calculations. For example, for aspartame, the affinity values for the above described metal ions are, respectively, 86.5, 63.2, 44.2, 255.4, 178.4, 235.4, and 300.4, and for β-glucose are 65.2, 47.3 32.9, 212.9, 140.2, 190.1, and 250.0 kcal mol−1, respectively. The study shows differences between the intrinsic chemistry of aspartame and glucose. 相似文献
168.
Alireza Aslani 《Inorganica chimica acta》2009,362(14):5012-5725
Nanoparticles of a new PbII metal-organic polymer, [Pb(μ-pyr)(μ-I)2]n (1), with a net-like morphology have been synthesized by the reaction of pyrazine with Pb(NO3)2 and NaI via sonochemical irradiation. Nano-structured PbI2 and PbO were synthesized from compound 1 by calcination at argon and air atmospheres, respectively. The structure of 1 was determined by single crystal X-ray crystallography and the nano-structures were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The thermal stability of nano-sized and single crystalline samples of 1 were studied and compared. 相似文献
169.
Alireza Shoae Hassani Feridon Malekzadeh Nour Amirmozafari Kasra Hamdi Negar Ordouzadeh Amir Ghaemi 《Current microbiology》2009,58(3):239-244
Exposure to ethanol is a stress condition that Salmonella typhimurium often encounters during its life cycle. Food, beverage, drugs, and cosmetics have a long history of using alcohols to control
pathogens. Ethanol is also commonly used for disinfecting medical instruments. This study was conducted to evaluate the ethanol
stress variations on the protein profile, cell structure, and serologic features of S. typhimurium. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis revealed the phage shock protein G (pspG), a new ethanol-induced
stress protein in cells adapted to 10% ethanol. The result was confirmed by liquid chromatography–mass spectrometry. The maximum
quantity of this 9.02-kDa protein was produced in 12.5% (v/v) of ethanol-treated cultures. Scanning electron microscopy has
demonstrated new phenotypic characteristics in bacterial structure. The cells were unable to undergo binary fission. This
phenomenon explains the tight attachment of bacteria in a colony. Overall, ethanol extreme stress induced expression of new
proteins like PspG and repression of some other proteins in S. typhimurium. These induction and repression processes have inflicted dramatic changes on Salmonella behaviors.
Alireza Shoae Hassani, Kasra Hamdi and Amir Ghaemi are members of Young Researchers Club (YRC) of Tehran Science & Research
Campus of IAU, Tehran, Iran. 相似文献
170.
Steroidogenesis depends on the delivery of free cholesterol to the inner mitochondrial membrane by StAR (steroidogenic acute regulatory protein). Mutations in the StAR gene leads to proteins with limited cholesterol-binding capacity. This gives rise to the accumulation of cytoplasmic cholesterol, a deficit in steroid hormone production and to the medical condition of lipoid congenital adrenal hyperplasia. A detailed understanding of the mechanism of the specific binding of free cholesterol by StAR would be a critical asset in understanding the molecular origin of this disease. Previous studies have led to the proposal that the C-terminal alpha-helix 4 of StAR was undergoing a folding/unfolding transition. This transition is thought to gate the cholesterol-binding site. Moreover, a conserved salt bridge (Glu169-Arg188) in the cholesterol-binding site is also proposed to be critical to the binding process. Interestingly, some of the documented clinical mutations occur at this salt bridge (E169G, E169K and R188C) and in the C-terminal alpha-helix 4 (L275P). In the present study, using rationalized mutagenesis, activity assays, CD, thermodynamic studies and molecular modelling, we characterized the alpha-helix 4 mutations L271N and L275P, as well as the salt bridge double mutant E169M/R188M. The results provide experimental validation for the gating mechanism of the cholesterol-binding site by the C-terminal alpha-helix and the importance of the salt bridge in the binding mechanism. Altogether, our results offer a molecular framework for understanding the impact of clinical mutations on the reduction of the binding affinity of StAR for free cholesterol. 相似文献