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461.
462.
Herein, we provide a brief overview of the synthesis and applications of trifluoromethylpyridine (TFMP) and its derivatives in the agrochemical and pharmaceutical industries. Currently, the major use of TFMP derivatives is in the protection of crops from pests. Fluazifop-butyl was the first TFMP derivative introduced to the agrochemical market, and since then, more than 20 new TFMP-containing agrochemicals have acquired ISO common names. Several TFMP derivatives are also used in the pharmaceutical and veterinary industries; five pharmaceutical and two veterinary products containing the TFMP moiety have been granted market approval, and many candidates are currently undergoing clinical trials. The biological activities of TFMP derivatives are thought to be due to the combination of the unique physicochemical properties of the fluorine atom and the unique characteristics of the pyridine moiety. It is expected that many novel applications of TFMP will be discovered in the future.  相似文献   
463.
Most of the metabolic diseases of dairy cows occur within the first 2 wk after calving, and cows with a metabolic disease are prone to infectious diseases. Although metabolic diseases are generally recognized as a risk factor for infectious diseases owing to the associated decrease in immune function, the difference in immune status between cows with milk fever (MF) or displaced abomasum (DA) during the lactation period has not been clarified. Therefore, the peripheral blood leukocyte populations in 38 multiparous Holstein cows from 1 herd were analyzed after calving. The cows were divided into 3 groups according to health: 21 cows that remained clinically healthy throughout the experimental period (control group), 9 cows that had MF on the day of calving, and 8 cows with an onset of DA within 4 wk after calving. The T- and B-cell numbers were lowest at week 0, and they increased gradually after calving. There was no significant difference between the 3 groups in the number of each subset of leukocytes on the day of calving, but the number of CD8+ T-cells was significantly lower in the MF and DA groups than in the control group at week 1. The numbers of CD4+, CD8+, and WC1+ T-cells tended to be lower in the DA group than in control group from weeks 4 to 12, a tendency not observed in the MF group. These data suggest that when cows have DA around the time of calving, their lymphocyte numbers remain lower until 12 wk after calving.  相似文献   
464.
To investigate the presence of non-native anguillid eels in Japanese waters, 141 eels were collected from seven sampling sites throughout the Tone River system. Genetic species identification showed an extraordinary dominance of the non-native European eel Anguilla anguilla in the uppermost site of the study area. Estimation of age from otoliths suggested that the European eels were introduced into the river in the 1990s, corresponding to previous reports from other Japanese water systems. Comparison of the von Bertalanffy growth curve parameters indicated that the European eels caught in the Tone River system appeared to have a similar or even higher growth rate than the same species in the original habitats in Europe. The long-term inhabitation and the normal development of European eels in Japanese waters suggest that regulations prohibiting the release of non-native eels and safeguards against accidental escape from culture ponds must be strictly maintained in order to ensure the conservation of the native Japanese eel.  相似文献   
465.
466.
To detect prion protein, brains from 5 cattle naturally affected with bovine spongiform encephalopathy (BSE) and 3 sheep naturally affected with scrapie were examined and compared with brains of normal cattle and sheep using a histoblot technique. The technique enabled the in situ distinctive detection of the cellular (PrP(C)) and abnormal (PrP(Sc)) isoforms of the prion protein. In BSE- or scrapie-affected brains, the Prp(C) signal decreased, especially in those areas where the PrP(Sc) signal was detected.  相似文献   
467.
The incidence, distribution, and macro‐ and microscopic structures of left ventricular false tendons (LVFTs) in the cat heart were studied using 25 normal and 57 diseased hearts. The fibrous bands were observed in the left ventricle of all 82 cat hearts examined and most commonly extended between the papillary muscles and the ventricular septum. Histologically, the LVFTs were composed of central Purkinje fibres and surrounding dense collagenous fibres covered by endothelium. There was no appreciable difference in the incidence, distribution or morphology of LVFTs between the normal and the diseased hearts, indicating that LVFTs are a common anatomic variant in the cat heart.  相似文献   
468.
The distribution of lectin bindings in the testis of the smallest ruminant, lesser mouse deer (Tragulus javanicus), was studied using 12 biotinylated lectins specific for d ‐galactose (peanut agglutinin PNA, Ricinus communis agglutinin RCA I), N‐acetyl‐d ‐galactosamine (Dolichos biflorus agglutinin DBA, Vicia villosa agglutinin VVA, Soybean agglutinin SBA), N‐acetyl‐d ‐glucosamine and sialic acid (wheat germ agglutinin WGA, s‐WGA), d ‐mannose and d ‐glucose (Lens culinaris agglutinin LCA, Pisum sativum agglutinin PSA, Concanavalin A Con A), l ‐fucose (Ulex europaeus agglutinin UEA I), and oligosaccharide (Phaseolus vulgaris agglutinin PHA‐E) sugar residues. In Golgi‐, cap‐, and acrosome‐phase spermatids, lectin‐bindings were found in the acrosome (PNA, RCA I, VVA, SBA, WGA and s‐WGA), and in the cytoplasm (PNA, RCA I, VVA, SBA, WGA, LCA, PSA, Con A and PHA‐E). s‐WGA binding was confined to the spermatid acrosome, but other lectins were also observed in spermatocytes. In spermatogonia, VVA, WGA, Con A, and PHA‐E bindings were observed. Sertoli cells were intensely stained with DBA and Con A, and weakly with PHA‐E. In interstitial Leydig cells, RCA I, DBA, VVA, Con A, PSA, LCA, WGA and PHA‐E were positive. UEA I was negative in all cell types including spermatogenic cells. Unusual distribution of lectin‐bindings noted in the testis of lesser mouse deer included the limited distribution of s‐WGA only in the spermatid acrosome, the distribution of DBA in Sertoli cells, Leydig cells and lamina propria, and the absence of UEA I in all type cells. The present results were discussed in comparison with those of other animals and their possible functional implications.  相似文献   
469.
The 3D internal structure microscopy (3D-ISM) was applied to the equine ovary, which possesses peculiar structural characteristics. Stereolithography was applied to make a life-sized model by means of data obtained from 3D-ISM. Images from serially sliced surfaces contributed to a successful 3D reconstruction of the equine ovary. Photopolymerized resin models of equine ovaries produced by stereolithography can clearly show the internal structure and spatial localizations in the ovary. The understanding of the spatial relationship between the ovulation fossa and follicles and/or corpora lutea in the equine ovary was a great benefit. The peculiar structure of the equine ovary could be thoroughly observed and understood through this model.  相似文献   
470.
Abstract

Column experiments were conducted to analyze the effect of the temperature on the amounts of organic materials in the leachate, especially organic acids and methane, from samples of the plow layer soil amended with rice straw. Total amount of inorganic carbon in the leachate during the 30-d period of incubation in relation to the temperature was 18°C < 25°C ≤ 30°C > 37°C > 45°C. Total amount of organic carbon in the leachate was signiicantly larger under 45°C incubation than that at other temperatures.

Acetic acid was the dominant organic acid in the leachate regardless of the temperature. Butylic and propionic acids were also present in large amounts in the early and the late period of incubation of temperatures ranging between 18 and 37°C, while only acetic acid was the dominant organic acid during the 30-d period of incubation at 45°C.

The total amount of methane in leachate during the 30-d period of incubation was very small at 18°C, while very large at 25, 30, and 37°C. It decreased nearly to one half at 45°C compared with that at 30°C. Based on the values of δ13CH4 in the leachate, 3 different stages were recognized in the predominant processes of methane production in the submerged paddy soil amended with rice straw: the stage when methane production from CO2-B2 was predominant followed by the stages of methane production from acetic acid and from CO2-H2 in this order. The second stage coincided with the time of decrease of the organic acid contents in the leachate. Under 45°C incubation, methane production from CO2-H2 was predominant throughout the 30-d period of incubation.  相似文献   
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