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111.
Strain BCT-7112T was isolated in 1966 in Japan from a survey designed to obtain naturally occurring microorganisms as pure cultures in the laboratory for use as probiotics in animal nutrition. This strain, which was primarily identified as Bacillus cereus var toyoi, has been in use for more than 30 years as the active ingredient of the preparation TOYOCERIN®, an additive for use in animal nutrition (e.g. swine, poultry, cattle, rabbits and aquaculture). Despite the fact that the strain was initially classified as B. cereus, it showed significant genomic differences from the type strains of the B. cereus group that were large enough (ANI values below 92%) to allow it to be considered as a different species within the group. The polyphasic taxonomic study presented here provides sufficient discriminative parameters to classify BCT-7112T as a new species for which the name Bacillus toyonensis sp. nov. is proposed, with BCT-7112T (=CECT 876T; =NCIMB 14858T) being designated as the type strain. In addition, a pairwise comparison between the available genomes of the whole B. cereus group by means of average nucleotide identity (ANI) calculations indicated that besides the eight classified species (including B. toyonensis), additional genomospecies could be detected, and most of them also had ANI values below 94%. ANI values were on the borderline of a species definition only in the cases of representatives of B. cereus versus B. thuringiensis, and B. mycoides and B. weihenstephanensis.  相似文献   
112.
The leopard seal is widely distributed on the Antarctic pack ice, but a number of individuals are also thought to displace north from the pack ice to the sub-Antarctic Islands or venture even farther north. In Chile, the leopard seal has been reported mainly in the Fueguian Archipelago, with individuals sighted year-round; however, the data to date have been unable to determine whether it is the same individuals who remain year-round. Thus, one of the questions to be resolved is whether there is a northward dispersion of individuals from the Southern Ocean returning to the Antarctic continent, or alternatively if there is a potential sub-Antarctic population that delay or suspend their migration toward the Antarctic region. Opportunistic sightings of a solitary seal at Ballena Sound (53°41′S, 72°37′W), Magellan Region, Chile, were documented in photographs on six occasions from January to May 2012. Based on the review of the photographs, the leopard seal was identified as the same individual. This finding provides the first evidence of a long occupation by a leopard seal in the fjords and channels of Fueguian Region, suggesting the existence of a small population inhabiting the waters of Southern Chile year-round.  相似文献   
113.
Truck drivers are more likely to suffer severe injury and death due to certain truck driving characteristics. Identifying and preventing factors associated with accidents in this population is important to minimize damage and improve road safety. Excessive daytime sleepiness is a major public health problem, leading to impaired cognitive function, reduced alertness, and increased risk of motor vehicle crashes. The aim of this cross‐sectional study was to determine the prevalence and predictors of hypersomnolence (defined as an Epworth Sleepiness Scale score greater than 10) among truck drivers. Three hundred male truck drivers were studied. Quality of sleep was assessed by the Pittsburgh Sleep Quality Index, and the association between demographic, clinical, and occupational data with excessive sleepiness was analyzed. The mean daily sleep duration was 5.6±1.3 h, and poor quality of sleep was found in 46.3% of the individuals. Hypersomnolence was found in 46% of the drivers and was associated with younger age, snoring, and working >10 h without rest. A positive correlation between hypersomnolence and previous accidents was detected (p=0.005). These results show that sleep deprivation and hypersomnolence are frequent among truck drivers. The treatment of sleep‐disordered breathing and the implementation of educational programs, particularly targeting younger drivers and promoting increased awareness of the deleterious effects of sleep loss and work overload, may help to reduce hypersomnolence and accidents among truck drivers.  相似文献   
114.
Until now, two species of Borgatomelissa Patiny, 2000 have been described, both from loci typici located in the Near East and eastern Africa. Borgatomelissa brevipennis (Walker, 1871), the most widespread taxon, has also been found in the southern Sahelo-Sudanian belt of the Sahara. A third species from eastern Morocco is described in the present study: Borgatomelissa flavimaura n. sp. In addition to taxonomic insights, the new species sheds a new light on the biogeography of the genus.  相似文献   
115.
116.
The pedunculopontine nucleus (PPN), the cholinergic arm of the reticular activating system, regulates waking and rapid eye movement sleep. Here, we demonstrate immunohistochemical labeling of the leptin receptor signaling isoform in PPN neurons, and investigated the effects of G‐protein modulation and the leptin triple antagonist (TA) on the action of leptin in the PPN. Whole‐cell patch clamp recordings were performed in rat brainstem slices from 9 to 17 day old pups. Previous results showed that leptin caused a partial blockade of sodium (INa) and h‐current (IH) in PPN neurons. TA (100 nM) reduced the blockade of INa (~ 50% reduction) and IH (~ 93% reduction) caused by leptin. Intracellular guanosine 5′‐[β‐thio]diphosphate trilithium salt (a G‐protein inhibitor) significantly reduced the effect of leptin on INa(~ 60% reduction) but not on IH (~ 25% reduction). Intracellular GTPγS (a G‐protein activator) reduced the effect of leptin on both INa (~ 80% reduction) and IH (~ 90% reduction). These results suggest that the effects of leptin on the intrinsic properties of PPN neurons are leptin receptor‐ and G‐protein dependent. We also found that leptin enhanced NMDA receptor‐mediated responses in single neurons and in the PPN population as a whole, an effect blocked by TA. These experiments further strengthen the association between leptin dysregulation and sleep disturbances.

  相似文献   

117.
The stimulation by Mg2+, Na+, K+, NH4 +, and ATP of (Na+, K+)-ATPase activity in a gill microsomal fraction from the freshwater prawn Macrobrachium rosenbergii was examined. Immunofluorescence labeling revealed that the (Na+, K+)-ATPase α-subunit is distributed predominantly within the intralamellar septum, while Western blotting revealed a single α-subunit isoform of about 108 kDa M r. Under saturating Mg2+, Na+, and K+ concentrations, the enzyme hydrolyzed ATP, obeying cooperative kinetics with V M = 115.0 ± 2.3 U mg?1, K 0.5 = 0.10 ± 0.01 mmol L?1. Stimulation by Na+ (V M = 110.0 ± 3.3 U mg?1, K 0.5 = 1.30 ± 0.03 mmol L?1), Mg2+ (V M = 115.0 ± 4.6 U mg?1, K 0.5 = 0.96 ± 0.03 mmol L?1), NH4 + (V M = 141.0 ± 5.6 U mg?1, K 0.5 = 1.90 ± 0.04 mmol L?1), and K+ (V M = 120.0 ± 2.4 U mg?1, K M = 2.74 ± 0.08 mmol L?1) followed single saturation curves and, except for K+, exhibited site–site interaction kinetics. Ouabain inhibited ATPase activity by around 73 % with K I = 12.4 ± 1.3 mol L?1. Complementary inhibition studies suggest the presence of F0F1–, Na+-, or K+-ATPases, but not V(H+)- or Ca2+-ATPases, in the gill microsomal preparation. K+ and NH4 + synergistically stimulated enzyme activity (≈25 %), suggesting that these ions bind to different sites on the molecule. We propose a mechanism for the stimulation by both NH4 +, and K+ of the gill enzyme.  相似文献   
118.
Several mite species commonly attack cultivated citrus around the world. Up to 104 phytophagous species have been reported causing damage to leaves, buds and fruits, but only a dozen can be considered major pests requiring control measures. In recent years, several species have expanded their geographical range primarily due to the great increase in trade and travel worldwide, representing a threat to agriculture in many countries. Three spider mite species (Acari: Tetranychidae) have recently invaded the citrus-growing areas in the Mediterranean region and Latin America. The Oriental red mite, Eutetranychus orientalis (Klein), presumably from the Near East, was detected in southern Spain in 2001. The Texas citrus mite, Eutetranychus banksi (McGregor), is widely distributed in North, Central and South America. It was first reported in Europe in 1999 on citrus in Portugal; afterwards the mite invaded the citrus orchards in southern Spain. In Latin America, the Hindustan citrus mite, Schizotetranychus hindustanicus (Hirst), previously known only from citrus and other host plants in India, was reported causing significant damage to citrus leaves and fruits in Zulia, northwest Venezuela, in the late 1990s. Later, this mite species spread to the southeast being detected on lemon trees in the state of Roraima in northern Brazil in 2008. Whereas damage levels, population dynamics and control measures are relatively well know in the case of Oriental red mite and Texas citrus mite, our knowledge of S. hindustanicus is noticeably scant. In the present paper, information on pest status, seasonal trends and natural enemies in invaded areas is provided for these species, together with morphological data useful for identification. Because invasive species may evolve during the invasion process, comparison of behavior, damage and management options between native and invaded areas for these species will be useful for understanding the invader’s success and their ability to colonize new regions.  相似文献   
119.
Suspension-cultured cells of Vitis vinifera cv Monastrell were used to investigate the effects of methyljasmonate, ethylene and salicylic acid separately or in combination with cyclodextrins on both trans-resveratrol production and the induction of defense responses.  相似文献   
120.
Thirty-one endophytic bacteria isolated from healthy leaves of Centella asiatica were screened in vitro for their ability to reduce the growth rate and disease incidence of Colletotrichum higginsianum, a causal agent of anthracnose. Isolates of Cohnella sp., Paenibacillus sp. and Pantoea sp. significantly stimulated the growth rate of C. higginsianum MUCL 44942, while isolates of Achromobacter sp., Acinetobacter sp., Microbacterium sp., Klebsiella sp. and Pseudomonas putida had no influence on this plant pathogen. By contrast, Bacillus subtilis BCA31 and Pseudomonas fluorescens BCA08 caused a marked inhibition of C. higginsianum MUCL 44942 growth by 46 and 82 %, respectively. Cell-free culture filtrates of B. subtilis BCA31 and P. fluorescens BCA08 were found to contain antifungal compounds against C. higginsianum MUCL 44942. Inoculation assays on in vitro-cultured plants of C. asiatica showed that foliar application of B. subtilis BCA31, three days before inoculation with C. higginsianum MUCL 44942, significantly reduced incidence and severity of the disease. The role of endophytic bacteria in maintaining the apparent inactivity of C. higginsianum MUCL 44942 in C. asiatica grown in the wild is discussed.  相似文献   
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