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81.
A factorial experiment based on RCB design with three replicates was conducted to investigate changes in some physiological responses of two chickpea (Cicer arietinum L.) cultivars (Pirouz from Desi type and ILC482 from Kabuli type) to arbuscular mycorrhiza (Glomus etunicatum Becker and Gerdman) under different irrigation treatments. The experiment was carried out in the greenhouse of the Agricultural Faculty of Kurdistan University from April to August 2009. The results showed that leaf chlorophyll content of chickpea cultivars was significantly increased by arbuscular mycorrhiza (AM) under both well and limited irrigation conditions. Proline accumulation in chickpea leaves under moderate and severe drought stresses was significantly stronger than that under optimum irrigation. Inoculation of chickpea with mycorrhizal fungi caused an increase in the activities of polyphenol oxidase and peroxidase, but a decrease in the activity of catalase. Comparisons among different irrigation levels showed that chickpea plants under drought stress had the most active lipid peroxidation. Non-AM plants showed stronger lipid peroxidation under moderate and severe water stresses than AM plants. Lipid peroxidation was more active in Pirouz leaves than in ILC482 leaves. It seems that Kabuli-type cultivar responded better to mycorrhizal symbiosis under drought stress than Desitype cultivar.  相似文献   
82.
Background and Aims: Helicobacter pylori is a highly diverse pathogen, which encounters epithelial cells as the initial defense barrier during its lifelong infection. The structure of epithelial cells can be disrupted through cleavage of microfilaments. Cytokeratin 18 (CK18) is an intermediate filament, the cleavage of which is considered an early event during apoptosis following activation of effector caspases. Methods: Helicobacter pylori strains were isolated from 76 dyspeptic patients. cagA 3’ variable region and CagA protein status were analyzed by PCR and western blotting, respectively. Eight hours post‐co‐culture of AGS cells with different H. pylori strains, flow cytometric analysis was performed using M30 monoclonal antibody specific to CK18 cleavage‐induced neo‐epitope. Results: Higher rates of CK18 cleavage were detected during co‐culture of AGS cells with H. pylori strains bearing greater numbers of cagA EPIYA‐C and multimerization (CM) motifs. On the other hand, H. pylori strains with greater numbers of EPIYA‐B relative to EPIYA‐C demonstrated a decrease in CK18 cleavage rate. Thus, H. pylori‐mediated cleavage of CK18 appeared proportional to the number of CagA EPIYA‐C and CM motifs, which seemed to be downplayed in the presence of EPIYA‐B motifs. Conclusions: Our observation associating the heterogeneity of cagA variants with the potential of H. pylori strains in the induction of CK18 cleavage as an early indication of apoptosis in gastric epithelial cells supports the fact that apoptosis may be a type‐specific trait. However, additional cagA‐targeted experiments are required to clearly identify the role of EPIYA and CM motifs in apoptosis and/or the responsible effector molecules.  相似文献   
83.
Polysaccharide-protein gums are complex polymers with many applications in emulsion and emulsion-based products. It is crucial to enclose a concept on understanding of functional properties of polysaccharide-protein biopolymer in order to select the appropriate one based on the application scope. The main objective of the current study was to investigate the effect of three extraction variables on the surface activity, particle uniformity, apparent viscosity, and protein content of a natural polysaccharide-protein biopolymer from durian fruit seed. Three extraction variables namely water: seed (W/S) ratio (20:1?C60:1), temperature (25.0?C85.0?°C) and pH (4.0?C10.0) were considered as independent variables. The results indicated that durian seed gum induced very low viscosity (0.93?C4.98?mPa.s) with pseudoplastic rheological behavior in the aqueous system. The current study revealed that the extraction variables had the most significant (p?<?0.05) effect on the emulsifying surface activity of the natural biopolymer from durian fruit seed. This might be due to the significant (p?<?0.05) effect of the proteineous constituent present in the chemical structure of the biopolymer from durian fruit seed. The aqueous extraction variables showed the most and least significant (p?<?0.05) effect on the specific surface area and protein content, respectively. Among all extraction variables, W/S ratio and pH exhibited the highest and lowest significant (p?<?0.05) effect on the physicochemical and functional properties of the natural biopolymer from durian fruit seed.  相似文献   
84.

Background

The aim of this study was to assess the feasibility of injury specific home safety investigation and to examine the home safety status focused on burn related safety in a rural population in the North-West of Iran.

Methods

A cross-sectional study was conducted on 265 rural households of rural Meshkinshahr, Iran. Cluster sampling method was used in 38 clusters with 7 households in each cluster. Clusters were selected on a probability proportional to size (PPS) basis using the available health census database called D-Tarh. Data were analyzed using the statistical software package STATA 8.

Results

Possible risks were explored in fields of house structure; cooking and eating attitudes and behaviors; cooking appliances, specific appliances such as picnic gas burners, valors (traditional heaters), samovars (traditional water boilers), and air-heating appliances. Many safety concerns were explored needing to draw the attention of researchers and public health policy makers.

Conclusion

Injury specific home safety surveys are useful and may provide useful information for safety promotion interventions.  相似文献   
85.
A sensitive and rapid method is described for determination of clopidogrel carboxylic acid (CCA), the inactive metabolite of anti platelet agent, clopidogrel, in human serum. The analytical procedure involves liquid-liquid extraction of the analyte and an internal standard (phenytoin) with ethyl acetate. A mobile phase consisting of 0.05 M phosphate buffer containing triethylamine (0.5 mL/L; pH 5.7) and acetonitrile (56:44 v/v) was used and chromatographic separation was achieved using C18 analytical column at detector wavelength of 220 nm. The calibration curves were linear over a concentration range of 0.05-10 microg/mL of CCA in human serum. The total run time of analysis was 5.5 min and the lower limits of detection (LOD) and quantification (LOQ) were 0.02 and 0.05 microg/mL, respectively. The method validation was carried out in terms of specificity, sensitivity, linearity, precision, accuracy and stability. The validated method was applied in a randomized cross-over bioequivalence study of two different clopidogrel preparations in 24 healthy volunteers.  相似文献   
86.
A new straightforward method based on cloud-point extraction (CPE) has been developed, optimized and validated for the determination of venlafaxine in human plasma by reversed-phase high-performance liquid chromatography with fluorescence detection. The non-ionic surfactant Triton X-114 (polyethylene glycol tert-octylphenyl ether) was chosen as the extract solvent. Separation was obtained using a reversed-phase Diamonsil column (C(18), 250mmx4.6mm I.D., 5mum) and a mobile phase composed of acetonitrile-phosphate buffer solution (pH 3.0)-triethylamine (33.5:66.5:0.4). Fluorescence detection was used (lambda(ex) 276nm, lambda(em) 598nm). Maprotiline was used as the internal standard. Under the optimum conditions, the linear range of venlafaxine in human plasma was 10-800ngmL(-1) (r(2)=0.9995). The limit of detection (LOD) was less than 2ngmL(-1) (S/N=3) and the limit of quantification (LOQ) was less than 10ngmL(-1) (S/N=10). The method was successfully applied for the evaluation of pharmacokinetic profiles of venlafaxine capsules in nine healthy volunteers.  相似文献   
87.
Fibroblast growth factor 23 (FGF-23) and Klotho are secretory proteins that regulate mineral-ion metabolism. Fgf-23(-/-) or Klotho(-/-) knockout mice exhibit several pathophysiological processes consistent with premature aging including severe atrophy of tissues. We show that the signal transduction pathways initiated by FGF-23-Klotho prevent tissue atrophy by stimulating proliferation and preventing apoptosis caused by excessive systemic vitamin D. Because serum levels of active vitamin D are greatly increased upon genetic ablation of Fgf-23 or Klotho, we find that these molecules have a dual role in suppression of apoptotic actions of vitamin D through both negative regulation of 1alpha-hydroxylase expression and phosphoinositide-3 kinase-dependent inhibition of caspase activity. These data provide new insights into the physiological roles of FGF-23 and Klotho.  相似文献   
88.
Identification of Botrytis spp. on Plants Grown in Iran   总被引:1,自引:0,他引:1  
A total of 363 isolates were collected from all over Iran. They were isolated from apple, arum lily, briar rose, bride wort, broad bean, camellia, canola, carnation, cucumber, egg plant, feijoa, geranium, gerbera, gladiolus, grape, guilder rose, hibiscus, iris, kiwifruit, oleander, onion, orange, pear, pomegranate, primrose, quince, redbud, robinia, rose, rubber plant, sow thiste, spathe flower, strawberry, tomato, violet, wall flower and wheat. To identify the species, morphological characters such as conidiophore length, conidial and sclerotial dimensions were measured. According to morphological and cultural characters, eight Botrytis species were identified: B. aclada sensu lato, B. cinerea, B. fabae, B. convoluta, B. gladiolorum, B. paeoniae, B. pelargonii and B. porri. As far as we are aware, this is the first report of the last five species from Iran. These species were examined by polymerase chain reaction (PCR) using necrosis and ethylene‐inducing protein (NEP2) and C729 primers. A 835 bp band was amplified in B. cinerea, B. fabae and B. pelargonii, using NEP2, but not in others. However, C729 primers amplified a 700 bp band in B. cinerea and B. pelargonii and a 600 bp in B. fabae.  相似文献   
89.
The genetic diversity among 10 Iranian bread wheat (Triticum aestivum) genotypes was analysed using 12 quality traits, 320 amplified fragment length polymorphisms (AFLP) polymorphic fragments, 491 simple sequence repeats (SSR) alleles and 294 proteome markers. The results revealed that the genotypes differed for quality traits, AFLP, SSR and proteome markers. The average genetic diversity based on quality traits (0.684 with a range of 0.266–0.997) was higher than AFLP (0.502 with a range of 0.328–0.717), SSR (0.503 with a range of 0.409–0.595) and proteome (0.464 with a range of 0.264–0.870) markers. Although there were apparent similarities between the groupings of particular genotypes, the overall correspondence between the distance matrices appeared to be rather low. In this study, the cluster analysis based on AFLP data showed the closest agreement with genotypes’ regions of origin or pedigree information. In addition to the genetic diversity assessment, specific proteins with known function were detected uniquely for the studied genotypes. Our results suggest that the classification based on quality traits and genotypic markers of these wheat genotypes will be useful for wheat breeders to plan crosses for positive traits.  相似文献   
90.
An efficient method for producing doubled haploid plants of oilseed rape (Brassica napus L.) was established using in vitro colchicine treatment of haploid embryos. Haploid embryos in the cotyledonary stage were treated with one of four colchicine concentrations (125, 250, 500 and 1,000 mg/L); for one of three treatment durations (12, 24 and 36 h) at one of the two temperatures (8 and 25°C) and were compared to control embryos (without colchicine treatment). The number of chromosomes, seed recovery, size and density of leaf stomata, and pollen grain size from regenerated plants were determined. No doubled haploid plants were regenerated from control embryos; however, the doubled haploid plants were regenerated from colchicine-treated embryos. A high doubling efficiency, 64.29 and 66.66% of regenerated plants, was obtained from 250 mg/L colchicine treatment for 24 h and 500 mg/L colchicine treatment for 36 h, respectively, at 8°C. Following 500 mg/L colchicine treatment for 36 h, a few plants regenerated (9 plants). At the higher colchicine concentration (1,000 mg/L), no plant regenerated. These results indicate that the colchicine treatment of embryos derived from microspores can induce efficient chromosome doubling for the production of doubled haploid lines of oilseed rape.  相似文献   
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