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941.
Ashish Kumar Srivastava Vinayak H. Lokhande Vikas Y. Patade Penna Suprasanna Rinaldi Sjahril Stanislaus Francis D’Souza 《Acta Physiologiae Plantarum》2010,32(6):1135-1144
The present study was aimed to evaluate the effect of different seed priming methods to enhance the sodium chloride (NaCl)
and polyethylene glycol-8000 (PEG-8000) stress tolerance in Indian mustard (Brassica juncea L.). Seeds subjected to different priming treatments such as water (hydro-priming), calcium chloride (CaCl2) (chemo-priming), and abscisic acid (ABA) (hormonal-priming) showed increased rate of germination as compared to non-primed
seeds. The primed and non-primed seeds were grown for 15 days and then the seedlings were independently subjected to iso-osmotic
salt (150 mM NaCl) or PEG-8000 (20%) stress. The different biochemical responses were studied 10 days after treatment. Under
NaCl and PEG stress, the dry weight and total chlorophyll content were higher in primed sets as compared to non-primed treatment
which was also evident by the phenotype of the seedlings. In general, the higher activities of superoxide dismutase and glutathione
reductase resulted in lower oxidative damage, in terms of malondialdehyde content, under NaCl and PEG stress in hydro-primed
set as compared to non-primed, ABA-, and CaCl2-primed treatments. Besides, the level of total phenolics and accumulation of osmolytes such as free proline, glycine betaine,
and total soluble sugars was also lower in hydro-primed set as compared to other primed and non-primed treatments. The study
thus suggests the use of hydro-priming as a simple and cost-effective strategy to alleviate the NaCl and PEG induced stress
in B. juncea. 相似文献
942.
943.
Donald M Gardiner Kemal Kazan Sebastien Praud Francois J Torney Anca Rusu John M Manners 《BMC plant biology》2010,10(1):289
Background
The fungal pathogen Fusarium graminearum causes Fusarium Head Blight (FHB) disease on wheat which can lead to trichothecene mycotoxin (e.g. deoxynivalenol, DON) contamination of grain, harmful to mammalian health. DON is produced at low levels under standard culture conditions when compared to plant infection but specific polyamines (e.g. putrescine and agmatine) and amino acids (e.g. arginine and ornithine) are potent inducers of DON by F. graminearum in axenic culture. Currently, host factors that promote mycotoxin synthesis during FHB are unknown, but plant derived polyamines could contribute to DON induction in infected heads. However, the temporal and spatial accumulation of polyamines and amino acids in relation to that of DON has not been studied. 相似文献944.
Background
It is widely accepted that orthologous genes between species are conserved at the sequence level and perform similar functions in different organisms. However, the level of conservation of gene expression patterns of the orthologous genes in different species has been unclear. To address the issue, we compared gene expression of orthologous genes based on 2,557 human and 1,267 mouse samples with high quality gene expression data, selected from experiments stored in the public microarray repository ArrayExpress. 相似文献945.
Ariane Germeyer Michael von Wolff Julia Jauckus Thomas Strowitzki Tanuj Sharma Anna T Grazul-Bilska 《Reproductive biology and endocrinology : RB&E》2010,8(1):67
Background
Reproductive failure, determined as recurrent spontaneous abortions (RSA) or recurrent implantation failure (RIF) in women is not well understood. Several factors, including embryo quality, and cellular and molecular changes in endometrium may contribute to the insufficient feto-maternal interaction resulting in reproductive failure. Prior clinical studies suggest an inadequate endometrial growth and development of the endometrium, leading to a lesser endometrial thickness. 相似文献946.
This article deals with the order of verbal suffixes in Adyghe, a polysynthetic language of the Caucasus. Traditionally the
structure of the Adyghe word form and the order of its affixes were described in terms of template morphology. However, we
present new data demanding another, substantially different approach. We demonstrate that for the most part suffix ordering
within the Adyghe verb follows strictly compositional rules. This feature is a manifestation of the polysynthetic nature of
the language. 相似文献
947.
Brugada syndrome (BrS) is a life-threatening cardiac rhythm disorder characterized by persistent STsegment elevation in leads
V1–V3 and right bundle branch block on electrocardiograms (ECG), and by syncope and sudden death from ventricular tachycardia
(VT) and ventricular fibrillation (VF). BrS is responsible for nearly 4% of sudden cardiac deaths and considered to be the
most common cause of natural death in males younger than 50 years in some Asian countries. Since the first diseasecausing
gene for BrS (the cardiac sodium channel gene SCN5A) was identified in 1998, extensive investigations on both clinical and basic aspects of BrS have occurred rapidly. SCN5A mutations remain the most common cause of BrS; nearly 300 SCN5A mutations have been identified and are responsible for 20%–30% of BrS cases. Commercial genetic testing is available for
SCN5A. Recently, seven other disease-causing genes for BrS have been identified and include GPD1L (BrS2), CACNA1C (Cav1.2, BrS3), CACNB2 (Cavβ2, BrS4), SCN1B (Navβ1, BrS5), KCNE3 (MiRP2, BrS6), SCN3B (Navβ3, BrS7), and HCN4 (BrS8). This article will briefly review the progress made over the past decade in our understanding of the clinical, genetic
and molecular aspects of BrS. 相似文献
948.
The distribution and ecology of four threatened lichens in the Czech Republic, Evernia mesomorpha, Hyperphyscia adglutinata, Hypotrachyna revoluta and Parmotrema perlatum, have been studied. All species are mainly epiphytic, but recent records from the Czech Republic are largely from siliceous
rocks in river/brook valleys. Changes in distribution and substrate preferences are documented and discussed. 相似文献
949.
Ali Izadi-Darbandi Bahman Yazdi-Samadi Ali-Akbar Shanejat-Boushehri Mohsen Mohammadi 《Journal of genetics》2010,89(2):193-199
Proline and glutamine-rich wheat seed endosperm proteins are collectively referred to as prolamins. They are comprised of
HMW-GSs, LMW-GSs and gliadins. HMW-GSs are major determinants of gluten elasticity and LMW-GSs considerably affect dough extensibility
and maximum dough resistance. The inheritance of glutenin subunits follows Mendelian genetics with multiple alleles in each
locus. Identification of the banding patterns of glutenin subunits could be used as an estimate for screening high quality
wheat germplasm. Here, by means of a two-step 1D-SDS-PAGE procedure, we identified the allelic variations in high and low-molecular-weight
glutenin subunits in 65 hexaploid wheat (Triticum aestivum L.) cultivars representing a historical trend in the cultivars introduced or released in Iran from the years 1940 to 1990.
Distinct alleles 17 and 19 were detected for Glu-1 and Glu-3 loci, respectively. The allelic frequencies at the Glu-1 loci demonstrated unimodal distributions. At Glu-A1, Glu-B1 and Glu-D1, we found that the most frequent alleles were the null, 7 + 8, 2 + 12 alleles, respectively, in Iranian wheat cultivars.
In contrast, Glu-3 loci showed bimodal or trimodal distributions. At Glu-A3, themost frequent alleles were c and e. At Glu-B3 the most frequent alleles were a, b and c. At Glu-D3 locus, the alleles b and a, were the most and the second most frequent alleles in Iranian wheat cultivars. This led to a
significantly higher Nei coefficient of genetic variations in Glu-3 loci (0.756) as compared to Glu-1 loci (0.547). At Glu-3 loci, we observed relatively high quality alleles in Glu-A3 and Glu-D3 loci and low quality alleles at Glu-B3 locus. 相似文献
950.
Roberto Lomba Nicastro Mário Eidi Sato Marcos Zatti Da Silva 《Experimental & applied acarology》2010,50(3):231-241
Studies on artificial laboratory selections with milbemectin, stability of milbemectin resistance and possible cross-resistance with abamectin were carried out with Tetranychus urticae Koch to provide basic information for a milbemectin resistance management program. Selections for resistance and susceptibility to milbemectin were performed in a population of T. urticae, collected from a commercial chrysanthemum field in the State of São Paulo, Brazil. After six selections for resistance and five selections for susceptibility, susceptible (S) and resistant (R) strains of T. urticae to milbemectin were obtained. The resistance ratio (R/S) at the LC50 reached 409-fold value. The stability of milbemectin resistance was also studied under laboratory conditions, using a population with initial frequency of 75% of resistant mites. The frequencies of milbemectin resistance were evaluated monthly for a period of 7 months. In order to observe possible correlation between milbemectin and abamectin resistance, the frequencies of abamectin resistance were also evaluated for that population, during the same period. The frequency of milbemectin resistance decreased from 75 to 14.5%, while the percentage of abamectin resistant mites decreased from 57 to 9.1%, in 7 months. The frequencies of milbemectin and abamectin resistance were also evaluated in 25 field populations of T. urticae, collected from several crops in the State of São Paulo. The frequencies of milbemectin resistance varied from 4.1 to 89.5%, and of abamectin, from 7.0 to 90.5%. A positive and significant correlation was observed between the frequencies of milbemectin and abamectin resistance, indicating positive cross-resistance between these acaricides. The results indicate that abamectin should be avoided for managing milbemectin resistance in T. urticae. This is the first report on milbemectin resistance in T. urticae in Brazil. 相似文献