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111.
The in vitro growth inhibitory activities of 15 drugs against Babesia gibsoni were evaluated following establishment of a continuous culture isolate (Aomori isolate). The culture was successfully continued in an RPMI-1640 medium supplemented with 20% normal canine serum or fetal bovine serum in a humidified atmosphere containing 5% CO(2) and 5% O(2) at 37 degrees C. We used this isolate to evaluate the growth inhibitory effect of naphthoquinone (atovaquone), aromatic diamidine (diminazene and pentamidine), artemisinin compounds (artesunate and dihydroartemisinin), an iron chelator (deferoxamine), quinoline-containing compounds (quinine and chloroquine), macrolide antibiotics (azithromycin), lyncomycin antibiotics (clindamycin), tetracycline antibiotics (doxycycline and minocycline), imidazole antifungals (clotrimazole and ketoconazole), and a nitroimidazole antiprotozoal (metronidazole). Atovaquone and aromatic diamidine showed the highest activity; they were followed by artesunate compounds with nanomole levels of IC(50). Metronidazole did not exhibit activity against the parasite. Other drugs exhibited intermediate in vitro activities with micromole levels of IC(50). This is the first report to screen drug activities against B. gibsoni in vitro. The results of our study may support further in vitro drug evaluation for the establishment of therapeutic strategies against canine B. gibsoni infections.  相似文献   
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GM2 gangliosidosis variant 0 (human Sandhoff disease) is a lysosomal storage disease caused by simultaneous deficiencies of acid beta-hexosaminidase (Hex) A and Hex B due to an abnormality of beta-subunit, a common component in these enzyme molecules, which is coded by the HEXB gene. In the present study, a retrospective diagnosis was performed in 2 previous suspected cases of feline Sandhoff-like disease using a DNA test to detect the causative mutation identified previously in 4 cats in 2 other families of Japanese domestic cats. Enzymic analysis was also performed using stored leukocytes and plasma collected from the subject families in order to investigate the usefulness of enzymic diagnosis and genotyping of carriers. The DNA test suggested that the 2 cases were homozygous recessive for the mutation. Consequently, 6 cats homozygous for the same mutation have been found in 4 separate locations of Japan, suggesting that this mutant allele may be spread widely in the Japanese domestic cat populations. In enzymic analysis, Hex A and Hex B activities in leukocytes and plasma measured using 4-methylumbelliferyl N-acetyl-beta-D-glucosaminide as a substrate were negligible in affected cats, compared with those in normal and carrier cats. However, there was a wide overlap in enzyme activity between normal and carrier cats. Therefore, it was concluded that enzymic analysis is useful for diagnosis of affected cats, but is not acceptable for genotyping of carriers.  相似文献   
114.
Surveillance of the distribution of sand fly species is important for prediction of the risk and expansion of Leishmania infection in endemic and surrounding areas. In the present study, a simple and reliable method of typing New World Lutzomyia species circulating in endemic areas in Ecuador was established by using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) technique. PCR-RFLP of 18S ribosomal RNA (rRNA) genes with the restriction enzyme AfaI and subsequently HinfI successfully identified seven sand fly species in nine endemic areas in Ecuador. Although intraspecific genetic-diversity affecting the RFLP-patterns was detected in a species, the patterns were species specific. The method promises to be a powerful tool for the classification of New World Lutzomyia species.  相似文献   
115.
Lactic acid bacteria play an essential role in the food industry in the manufacture of many fermented products (cheese, yogurt, fermented vegetables, etc.). Application of these organisms is now being extended to the area of health improvement, as their probiotic activities become known. Probiotics are defined as viable microorganisms that exert a beneficial effect on the health of the host when they are ingested in sufficient quantity. Lactic acid bacteria and bifidobacteria isolated from the human intestine are the most common probiotics used for human consumption. The development of new probiotics with new beneficial effects is eagerly awaited in the food industry. This review introduces Lactococcus, which are one of the genera of lactic acid bacteria and are mainly isolated from dairy products and fermented vegetables, as new probiotics, focusing especially on Lactococcus lactis H61, which improves skin status in Japanese women with oral intake of heat‐killed or live cells. The deduced mechanisms associated with the beneficial effects of strain H61 are also discussed.  相似文献   
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With the aim of improving artificial androgenesis in teleost fishes, we tested two methods for producing androgenetic diploids of amago salmon (Oncorhynchus masou ishikawae), namely, fertilization of gamma-ray irradiated eggs with fused spermatozoa (sperm-fusion method) and the fertilization of irradiated eggs with untreated sperm followed by the blocking of cell division (mitosis-inhibition method). Our results showed that the optimal condition for sperm fusion was to treat the sperm with 50% polyethylene glycol (molecular weight 7500) for 100 s. The efficiency of the two methods of androgenesis was compared in terms of fertilization rate, hatching rate, and larval survival after hatching. The rate of fertilization was lower with the sperm-fusion method than with the mitosis-inhibition method, but the reverse was true for the hatching rate. The survival rate of hatched larvae was the same with the two methods. Androgenesis was confirmed with a recessive albino color marker, and all viable offspring were found to be heterozygous based on analysis of the microsatellite markers. Our results suggest that androgenesis with the sperm-fusion method is a promising approach with potential applications in both aquaculture breeding programs and the preservation of endangered freshwater fishes.  相似文献   
118.
Mass mortality due to necrosis signs occurred in hatchery-reared zoea stage larvae of the mud crab Scylla serrata in Okinawa, Japan, and a causative bacterium was isolated. In this study, we identified and characterized the bacterium by genome analysis, biochemical properties and pathogenicity. The bacterium was a Gram-negative, non-motile, long rod, forming yellow colonies on a marine agar plate. It grew at 20–33°C (not at 37°C) and degraded chitin and gelatin. Phylogenetic analysis of the 16S rRNA gene sequence identified the bacterium as Aquimarina hainanensis. Genome sequence data obtained from Illumina MiSeq generated 29 contigs with 3.56 Mbp in total length and a G + C content of 32.5%. The predicted 16 chitinase genes, as putative virulence factors, had certain homologies with those of genus Aquimarina. Experimental infection with the bacterium conducted on larvae of four crustacean species, brine shrimp Artemia franciscana, freshwater shrimp Caridina multidentata, swimming crab Portunus trituberculatus and mud crab S. serrata, revealed that this bacterium was highly virulent to these species. The present study suggests that the bacterium caused mass mortality in mud crab seed production was A. hainanensis and can be widely pathogenic to crustaceans.  相似文献   
119.
ABSTRACT

In this study, the functional components of 19 microalgae and 6 bivalve species were investigated in the context of the application in bivalve feeding and human health food. Principal component analysis was performed to detect any association between the functional components and individual microalgal species or taxonomic group. The proportions of the functional components differed depending on the taxonomic group or species of microalga. The genera Cheatoceros, Thalassiosira, and Isochrysis contained high concentrations of fucosterol and fucoxanthin, which are present in large amounts in brown algae. Diatoms, haptophytes, and eustigmatophytes, which are used as feed for bivalves, were rich in fucosterol and eicosapentenoic acid (EPA); further, haptophytes were rich in docosahexaenoic acid (DHA). In addition, the microalgae associated with red tide, i.e., the raphidophytes, were found to be rich in fucoxanthin, β-sitosterol, and EPA, whereas dinoflagellates were rich in DHA. Seven bivalve species also contained high concentrations of fucosterol, EPA, and DHA, as did microalgae, which were used to feed by bivalves. These results are useful in selecting microalgae effectively as feed of the bivalves.  相似文献   
120.
The red alga Kappaphycus alvarezii is economically important as an edible species and as a source of carrageenan, and has been extensively cultivated in many tropical countries. For this species, different color strains, which differ from each another in growth rate and carrageenan content, have been reported for decades. In this study, lectins from brown, red, and green strains of K. alvarezii cultivated in Vietnam were isolated and characterized for evaluation of their biochemical properties and contents. The results showed that each color strain contained in common the three lectins, named KAA-1, KAA-2, and KAA-3, which shared the hapten-inhibition profile of hemagglutination, 20 N-terminal amino acid sequence, and equivalent molecular mass within a range of 28,016 ± 1.2 to 28,021 ± 1.8 Da, but differed in their yields, with the highest yield of KAA-2. These properties of the three isolectins were also comparable among the three different color strains. However, the sum of the yields of the three isolectins decreased in the order: red (21.4 mg) to green (15.9 mg) to brown strains (15.1 mg), from 500 g fresh alga. Thus, this algal species can be a good source of useful lectins, irrespective of color strain.  相似文献   
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