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101.
How stem cells are recruited to and maintained in their niches is crucial to understanding their regulation and use in regenerative medicine. Here, we demonstrate that DE-cadherin-mediated cell adhesion is required for anchoring germline stem cells (GSCs) in their niches in the Drosophila ovary. Two major components of this adhesion process, DE-cadherin and Armadillo/beta-catenin, accumulate at high levels in the junctions between GSCs and cap cells, one of the niche components. Removal of these proteins from GSCs results in stem cell loss. Furthermore, DE-cadherin is required for recruiting GSCs to their niche. Our study demonstrates that anchorage of GSCs in their niche by DE-cadherin-mediated adhesion is important for stem cell maintenance and function. 相似文献
102.
Son Hai VU Bomin KIM Alisha Wehdnesday Bernardo REYES Tran Xuan Ngoc HUY John Hwa LEE Suk KIM Hyun-Jin KIM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(3):482
To better understanding Brucella abortus infection, serum metabolites of B. abortus-infected and -uninfected mice were analyzed and twenty-one metabolites were tentatively identified at 3 and 14 days post-infection (d.p.i.). Level of most lysophosphatidylcholines (LPCs) was found to increase in infected mice at 3 d.p.i., while it was decreased at 14 d.p.i. as compared to uninfected mice. In contrast, acylcarnitines were initially reduced at 3 d.p.i then elevated after two-weeks of infection, while hydroxysanthine was increased at 14 d.p.i. in infected mice. Our findings suggest that the significant changes in LPCs and other identified metabolites may serve as potential biomarkers in acute phase of B. abortus infection. 相似文献
103.
Shuichi Fukuoka Tran Danh Suu Kaworu Ebana Luu Ngoc Trinh Tsukasa Nagamine Kazutoshi Okuno 《Genetic Resources and Crop Evolution》2006,53(4):753-761
Phenotypic variation of agronomic characters in aromatic rice (Oryza sativa L.) was analyzed in order to elucidate the genetic diversity of the populations of rice landraces. Thirteen populations in
Namdinh province, in the Red River Delta of Vietnam, were studied in both of farmers fields and an experimental field. Only
small differences were found in agronomic characters among the populations, including populations containing different varieties.
Variations among the populations in the frequency distributions of several characters suggested different degrees of diversity
among the populations even among populations with the same variety name. The phenotypic profiles of farmers fields were different
from those in an experimental field suggesting the environmental differences between them. One variety cultivated in the Myloc
district had different phenotypic characters from the other varieties in the Haihau district more clearly in the experimental
field. Since the small phenotypic variation in each of farm might be due to the genetic drift and selection by the farmers,
on farm conservation of the landraces of rice is considered to be under a force to decrease phenotypic diversity. The present
study suggests that the targeting several farms with different phenotypic profiles contribute to the conservation of regional
genetic diversity of the landraces of rice. 相似文献
104.
H. I. Schiff G. I. Mackay C. Castledine G. W. Harris Q. Tran 《Water, air, and soil pollution》1986,30(1-2):105-114
A highly sensitive, lightweight, portable instrument has been developed for continuous monitoring of N02 in air. It operates by detecting the chemiluminescence produced when N02 encounters a surface wetted with a specially formulated solution containing luminol. Unlike other chemiluminescent instruments it measures N02 directly and does not require prior conversion of N02 to NO. It does not respond to H202, NO, HNO3, NH3, CO, C02, S02 or organic nitrates. The only interferences encountered to date are from 03 and PAN with the response to 03 being less than 0.2% of its response to N02. The response time of the instrument is less than 1 s and its sensitivity is better than 5 pptv. The instrument shows a negative temperature dependence of about 2% °C?1 which is compensated electronically. Measurements have been made with the instrument during a number of field missions in polluted urban and relatively clean rural air. The relative influences of photochemistry and transport from local sources has been observed. Simultaneous measurements made with this instrument and the unequivocal tunable diode laser absorption spectroscopy method have shown excellent agreement. 相似文献
105.
Genetic modification from selfed progenies of 18 rice (Oryza sativa L.) plants regenerated from callus tissues which survived desiccation, were investigated at the DNA level using the random
amplified polymorphic DNA (RAPD) method. Twelve 10-mer random primers were used to amplify DNA of progenies from the regenerated
plants, and a total of 228 PCR products and 1780 DNA fragments were obtained by primers, generating between four to thirteen
major bands. The size of the amplified fragments ranged from 0.2 to 2.55 kb. The results showed that 10 out of 12 primers
produced polymorphic bands, two primers (RA31 and RA185) showed no polymorphism among plants tested. A dendrogram of the genetic
distance was constructed based on their polymorphism, demonstrating that somaclonal variation exists in rice plants regenerated
from callus which survived the desiccation treatment. Part of this variation can be useful in rice breeding.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
106.
The Acph1 locus of Aegilops tauschii encodes a new electrophoretically ‘fast’ acid phosphatase, whose allelic variation could well be involved in intraspecies differentiation. Genetic mapping via microsatellite (simple sequence repeat) analysis revealed that Acph1 is tightly linked with the marker Xgwm157 near the centromere region of chromosome 2. 相似文献
107.
Decomposition of Allelopathic Plants in Soil 总被引:1,自引:0,他引:1
T. D. Xuan S. Tawata T. D. Khanh I. M. Chung 《Journal of Agronomy and Crop Science》2005,191(3):162-171
Higher plants with strong allelopathic properties are commonly incorporated into soil for weed-control purposes. To understand the phytotoxic variation in the soil, which can be utilized for weed control through the use of allelopathic plants, the decomposition of alfalfa (Medicago sativa L. cv. Rasen) and kava (Piper methysticum L.) after soil amendment were evaluated. Both alfalfa and kava strongly inhibited barnyardgrass and monochoria growth for up to 10 days (80–100 % weed control). After 20–25 days, the magnitude of inhibition was drastically reduced, but was still effective (50 % weed control). A number of phenolic acids were detected in the soil even 50 days after incorporation in low concentration, but their concentrations reached a maximum after 10–15 days and were efficacious until 20–25 days. Phenolic acids varied between alfalfa and kava. The variations in electrical conductivity (EC) and osmotic pressure (OP) were strongly related to chemicals and toxic compounds exuded into the soil during decomposition and were proportional to the magnitude of inhibition observed, whereas pH did not appear to be correlated with inhibition. The decomposition of several unknown inhibitors present in kava was also analysed and assessed. Our findings indicate that these growth inhibitors were almost disintegrated in soil after 10 days, but strong inhibition was detected until 25 days after amendment. Results from this study demonstrate that chemicals released from allelopathic plants incorporated into soil are toxic and cause inhibition of certain species and could be exploited as a biological tool for weed management. 相似文献
108.
Varietal Differences in Allelopathic Potential of Alfalfa 总被引:6,自引:0,他引:6
Alfalfa ( Medicago sativa L.) plants were found to contain water-soluble substances that inhibited the germination and seedling growth of alfalfa ( Chung and Miller 1990, Agron. J. 87, 762—767 ). Tsuzuki et al. (1999, Rep. Kyushu Branch Crop Sci. Soc. Japan 65, 39—40 ) discovered allelochemicals in alfalfa plants that could have adverse effects on the growth of some lowland weeds. This study was conducted to investigate varietal differences in allelopathic potential in alfalfa plants. Eight common varieties of Japanese alfalfa ( Medicago sativa L.), namely Batasu, Hisawakaba, Kitawakaba, Makiwakaba, Natsuwakaba, Lucerne, Tachiwakaba and Yuba, were grown by conventional methods in the Experimental Field of the Crop Science Laboratory, Faculty of Agriculture, Miyazaki University. Aqueous extracts of both fresh and dried material of alfalfa plants of all varieties significantly inhibited both germination and growth of lettuce ( Lactuca sativa L.). Leachates from germinating seeds of almost all alfalfa varieties inhibited elongation of the radicle but produced a negligible increase in germination and only slightly inhibited elongation of the hypocotyl of lettuce plants. Results demonstrated that the degree of inhibition of germination and growth of lettuce varied with the variety of alfalfa. In particular, Lucerne was identified as having the strongest allelopathic potential of the varieties studied. The results suggested that the allelopathic potential of alfalfa might be relating to a gene. 相似文献
109.
Van Ba Nguyen Nam Le Quang Do Duy Ngoc Van Hau Nguyen Pham Lan Doan 《Tropical animal health and production》2020,52(3):1033-1041
Tropical Animal Health and Production - The study aimed to characterize genetic diversity, genetic clusters, and phylogenetic relationships of 15 Vietnamese indigenous pig breeds across the country... 相似文献
110.
Khieokhajonkhet Anurak Aeksiri Niran Rojtinnakorn Jiraporn Van Doan Hien Kaneko Gen 《Aquaculture International》2022,30(2):677-698
Aquaculture International - The utilization of sustainable and innovative raw materials to substitute for traditional fishmeal (FM) ingredients is required for the aquaculture sector. Sacha inchi... 相似文献