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81.
Y. Miura    M. Hirata    M. Fujimori 《Plant Breeding》2007,126(4):353-360
New molecular markers derived from expressed sequence tag (EST) sequences were mapped on linkage maps of Italian ryegrass by a two-way pseudo-testcross strategy. cDNA sequences were obtained from various tissues of Italian ryegrass ( Lolium multiflorum ) and converted into cleaved amplified polymorphic sequence (CAPS) markers. Of 260 EST primer pairs that amplified a single band, 74 generated bands that showed clear polymorphisms among individuals of an F1 mapping family. Of the 74 polymorphic marker loci, 69 were mapped on an Italian ryegrass linkage map previously constructed using amplified fragment length polymorphism (AFLP), restriction fragment length polymorphism (RFLP), and simple sequence repeat (SSR) markers. The newly-developed EST-CAPS markers would be useful as an efficient tool to identify genetic markers and to identify candidate genes for quantitative trait loci (QTLs) associated with important traits in Italian ryegrass.  相似文献   
82.
Growing cloud droplets absorb such atmospheric gaseous pollutant as SO2(g), condensing atmospheric water vapor into themselves. Then, the cloud droplets are acidified by absorption of SO2(g) during condensational growth on cloud condensation nuclei (CCN). Characteristics of this process, which is a part of rainout, have not been made clear yet. In order to estimate the contribution of rainout to acid rain formation, the acidification of growing cloud droplets is investigated numerically, using a mathematical model. The numerical simulations show that: (1) the time to attain the equilibrium state for mass transfer (acidity and growth) and heat transfer (temperature) is much longer than the time for disappearance of CCN; (2) time variation of acidity and temperature of cloud droplets are greatly dependent on the existence of undissolved CCN; and (3) there seems to be a close correlation between the time variation of the acidity and that of the temperature.  相似文献   
83.
The aim of this work was to evaluate garlic diversity based on the production of chemical components in the bulbs and geographical distribution. A total of 103 garlic clones collected from worldwide sources were grown in Yamaguchi, Japan. The chemical contents–S-allyl-l-cysteine sulfoxide (AlCSO), and phenolic content—of garlic collections were determined by HPLC and Folin–Ciocalteu assay, respectively. Quantitative analysis of the chemical content showed wide variations between geographical collection sites. Morphological observation of inflorescence was performed, and clones were divided into four types according to their bolting traits: Type A—bolters, producing mainly florets; Type B—bolters, producing mainly bulbils; Type C—incomplete bolters; and Type D—non-bolters. The appearance frequencies of the bolting types varied depending on the latitude of the collection sites. A comparison of these four different types was carried out based on chemical composition data. Garlic clones that possessed florets showed a tendency for higher amount of AlCSO content than did Type B. Moreover, it was confirmed that as distance increased from high-latitude areas (Central Asia and The Northern Mediterranean), the garlic was more likely to produce bulbils in the inflorescence with lower AlCSO content and higher phenolic content. This research suggested that garlic’s transition of from sexual propagation to asexual (vegetative) propagation and changes in the chemical composition of the bulbs would have occurred in the process of expanding garlic cultivation. In conclusion, garlic seems to have obtained high environmental adaptability with these transitions and changes via artificial selection.  相似文献   
84.
An 11-year-old male Labrador retriever presented with chronic oliguria. Ultrasonography findings revealed a protruding mass at the neck of the urinary bladder. A cystotomy was performed, and the mass was removed by ligation with surgical sutures. Histopathological examination revealed conspicuous foci with a variable number of ganglion cells in the tumor and abundant interwoven bundles of schwannian cells with fine fibers. The ganglion cells were positive for neuron-specific enolase and neurofilament. The schwannian cells were positive for vimentin, S-100 protein, and glial fibrillary acidic protein. Thus, according to the classification of tumor with neuronal cell differentiation, the urinary tumor was diagnosed as a ganglioneuroma.  相似文献   
85.
This study was performed for the purpose of investigating the prevalence of Sarcocystis spp. in buffaloes in Beni-Suef Governorate, Egypt. Both macroscopic (Sarcocystis fusiformis) and microscopic (Sarcocystis levinei) cysts were recognized, and were differentiated by their morphological features and location in the tissues. Of 379 buffaloes examined in abattoirs in Beni-Suef, 299 were found to be infected, with an overall prevalence of 78.9%. Depending on age, three categorized groups of naturally infected buffaloes were examined: male buffalo calves aged 1.5–2 years, adult females aged 2–5 years, and females older than 5 years. Among these groups, infection rates were 74.5%, 82.3%, and 81.2%, respectively. Organs examined included esophagus, tongue, and heart. Macroscopic cysts were examined by the naked eye through meat inspection in abattoirs, while the pepsin-digestion method and the histological technique were applied to detect microscopic cysts. It has been found that esophagus showed the highest rate of infection among the infected organs, with both macroscopic and microscopic cysts seen in the infected buffaloes. Moreover, results of the pepsin-digestion method proved more accurate than those produced by the histological technique in terms of infection rates for the microscopic cysts. Our findings indicated that infected buffaloes aged 2–5 years showed the highest mixed infection rate (82.3%) for both types of cysts. The high prevalence of microscopic Sarcocystis spp. in Beni-Suef Governorate reflects a significant role played by stray dogs, rather than cats, in the transmission of these parasites.  相似文献   
86.
Asparagus (Asparagus officinalis L.) is a dioecious plant. In general, male and female plants are used for open-field culture and intensive cultivation, respectively. Farmers distinguish between the sexes by observing the form of the flower organs. However, because flowering begins 2?C3 years after planting, the sexes cannot be differentiated at transplantation by using this method, and planting of an all-male population is not possible. In this study, the usefulness of loop-mediated isothermal amplification (LAMP), a simple method of gene amplification, for sex distinction at the DNA level was determined. In addition, the phenotypic differences in seeds and seedlings of male and female plants were investigated for application as a method of early sex distinction. By using the LAMP method, the sex could be correctly identified in 100% of the seedlings, suggesting that this method is effective for sex distinction at the gene level. Principal component analysis was conducted with 11 selected parameters after investigating the seeds and seedlings of both male and female plants. The results revealed that male plants tend to have many stalks or cladophylls and female plants tend to have large plant forms, suggesting that the sexes can be distinguished by the external appearance of the seedlings before planting. LAMP and observation of the seedling phenotypes could be useful methods of sex distinction for increasing the efficiency of asparagus breeding.  相似文献   
87.
Prostaglandin D2 as a mediator of allergic asthma   总被引:1,自引:0,他引:1  
Allergic asthma is caused by the aberrant expansion in the lung of T helper cells that produce type 2 (TH2) cytokines and is characterized by infiltration of eosinophils and bronchial hyperreactivity. This disease is often triggered by mast cells activated by immunoglobulin E (IgE)-mediated allergic challenge. Activated mast cells release various chemical mediators, including prostaglandin D2 (PGD2), whose role in allergic asthma has now been investigated by the generation of mice deficient in the PGD receptor (DP). Sensitization and aerosol challenge of the homozygous mutant (DP-/-) mice with ovalbumin (OVA) induced increases in the serum concentration of IgE similar to those in wild-type mice subjected to this model of asthma. However, the concentrations of TH2 cytokines and the extent of lymphocyte accumulation in the lung of OVA-challenged DP-/- mice were greatly reduced compared with those in wild-type animals. Moreover, DP-/- mice showed only marginal infiltration of eosinophils and failed to develop airway hyperreactivity. Thus, PGD2 functions as a mast cell-derived mediator to trigger asthmatic responses.  相似文献   
88.
Devastating earthquakes occur on a megathrust fault that underlies the Tokyo metropolitan region. We identify this fault with use of deep seismic reflection profiling to be the upper surface of the Philippine Sea plate. The depth to the top of this plate, 4 to 26 kilometers, is much shallower than previous estimates based on the distribution of seismicity. This shallower plate geometry changes the location of maximum finite slip of the 1923 Kanto earthquake and will affect estimations of strong ground motion for seismic hazards analysis within the Tokyo region.  相似文献   
89.
Phospholipid methylation and biological signal transmission   总被引:64,自引:0,他引:64  
Many types of cells methylate phospholipids using two methyltransferase enzymes that are asymmetrically distributed in membranes. As the phospholipids are successively methylated, they are translocated from the inside to the outside of the membrane. When catecholamine neurotransmitters, lectins, immunoglobulins or chemotaxic peptides bind to the cell surface, they stimulate the methyltransferase enzymes and reduce membrane viscosity. The methylation of phospholipids is coupled to Ca2+ influx and the release of arachidonic acid, lysophosphatidylcholine, and prostaglandins. These closely associated biochemical changes facilitate the transmission of many signals through membranes, resulting in the generation of adenosine 3',5'-monophophate in many cell types, release of histamine in mast cells and basophils, mitogenesis in lymphocytes, and chemotaxis in neutrophils.  相似文献   
90.
Sphingolipids constitute a highly diverse and complex class of molecules and exhibit important physiological functions. Glucocerebrosides are anticipated to play a positive role in human nutrition. In this study, complicated glucocerebrosides from three specimens of edible sea cucumbers, specifically, Acaudina molpadioides, Cucumaria frondosa, and Apostichopus japonicus, were rapidly identified using liquid chromatography-ion trap-time-of-flight mass spectrometry (LCMS-IT-TOF), which is a powerful analysis tool. [M + H](+), [M + Na](+), and [M + H - H(2)O](+) in positive electrospray ionization (ESI) mode were used for MS/MS analysis to obtain product ion spectra. Various long-chain bases of glucocerebrosides were found in these sea cucumbers. Two of the most common long-chain bases were 2-amino-1,3-dihydroxy-4-heptadecene (d17:1) and 4,8-sphingadienine (d18:2), which were acylated to form saturated and monounsaturated nonhydroxy and monohydroxy fatty acids with 18-25 carbon atoms. The glucocerebroside molecular species were the most complicated in the sea cucumber C. frondosa and were the simplest in the sea cucumber A. molpadioides.  相似文献   
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