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11.
Eva-Britt Jakubek Roland Mattsson Torsten M?rner Jens G Mattsson Dolores Gavier-Widén 《Acta veterinaria Scandinavica》2012,54(1):13
Background
Serological surveys for disease investigation of wild animal populations require obtaining blood samples for analysis, which has logistic, ethic and economic difficulties. Applying serological test to fluids collected from dead animals is an alternative. The aim of this study was to assess if antibodies could be detected in two types of fluids collected from 56 carcasses of red foxes (Vulpes vulpes): pleural fluid and lung extract.Findings
In 22 (39%) foxes antibodies against Sarcoptes scabiei were detected in both fluid types by ELISA and Western blot. In 46 (82%) foxes, antibodies against Toxoplasma gondii were detected in pleural fluid and in 41 (73%) in lung extract applying a Toxo-screen test (DAT). Antibodies were still detectable in the same fluids kept at room temperature for 28 days, although in fewer foxes (16 and 14 foxes tested for T. gondii in lung extract and pleural fluid respectively; and 1 and 4 tested for S. scabiei in lung extract and pleural fluid respectively.Conclusions
These results indicate the potential utility of using fluids from carcasses for antibody screening of wild animals at the population level. 相似文献12.
Davina Van Goethem Sebastiaan De Smedt Roland Valcke Denis O'Connor Pat O'Connell Sonja Denollin Roeland Samson Geert Potters 《世界竹藤通讯》2012,10(5):46
在寻找可再生能源和生物基材料方面,竹子已经被作为一种高产的生物质产品,可以用来作为土壤污染的修复性植物。由于这个原因,一个产量指示的增长模型需要一个健康的指标参数来检测植物的性能。因此,本研究对位于爱尔兰都伯林的Ballyboughalo公司的毛竹蒿草(Phyllostachys humilis)叶子的叶绿素荧光进行了测量。本研究测量结果涵盖了这种竹类每个节点的叶子,并且建立在了随季节性变化的基础上。最常使用的叶绿素荧光参数是Fv/Fm值,又称TRO/ABS (即被困的光子与吸收的光子数之比)。随季节的推移以及这个参数较大的变化,本研究将春天与一年中其它的季节进行对比观察测量。在过去的一年,这种植物的上部叶片比下部叶片表现更好。本研究的发现被整合在一个数学模型中,其目的是为预测和解释在其它立地条件下的植物的性能。 相似文献
13.
Amblypygi are tropical and subtropical ambush predators that use elongated, raptorial pedipalps for different activities. Although pedipalp use in predation and courtship has been explored in videography in vivo analyses, kinematic ex vivo examination of these appendages has not been conducted. Here, we rectify this lack of data by using micro-CT scans to 3D-kinematically model the appendage morphology and the range of motion (ROM) of the joints for Damon medius and Heterophrynus elaphus. We illustrate the successful application of this technique to terrestrial euarthropods in determining the maximum ROM values for each pedipalp joint. We also note that, in life, these values would be lower due to motion restricting structures like tendons, arthrodial membranes, and muscles. We further compare our maximum values obtained here with data from video-based motion analyses. The ROM of each joint shows the greatest flexibility in the femur-tibia joint (140–150°), the lowest in the basitarsus-claw joint (35–40°). ROM in the tibia-basitarsus joint is markedly distinct (D. medius: 44°; H. elaphus: 105°). This disparity reflects how H. elaphus uses the joint in the capture basket, while D. medius uses the femur-tibia joint to form the capture basket. We further illustrate notable vertical motion of the H. elaphus pedipalp compared to D. medius. This difference reflects the retro-ventral trochanter apophysis of H. elaphus. Our study opens the possibility to further whip spider kinematic understanding. Examination of other taxa using this approach will result in a more comprehensive understanding of the ecological significance and ethological implications of this unique arachnid group. 相似文献
14.
Emma Fishbourne Evelyne Hutet Charles Abrams Roland Cariolet Marie-Frédérique Le Potier Haru-H Takamatsu Linda K Dixon 《Veterinary research》2013,44(1):87
Modulation of the expression of chemokines and chemokine receptors in whole blood was compared following infection of pigs with high and low virulence isolates of African swine fever virus. Levels of mRNAs for CCL2, CCL3L1, CCL4, CXCL10, CCR1 and CCR5 were significantly increased in at least one time point following infection in two experiments and CCL5, CCR9 and CXCR4 mRNA were significantly increased in one of the experiments. The results showed that greatest fold increases in mRNAs for CXCL10 and CCL2 were observed following infection of pigs. CXCL10 mRNA was increased by up to 15 fold in infected compared to uninfected pigs. CXCL10 protein was also detected in serum from pigs infected with the high virulence Benin 97/1 isolate. Levels of CCL2 mRNA were increased in pigs infected with high virulence Benin 97/1 isolate compared to low virulence OURT88/3 isolate and this correlated with an increase of greater than 30 fold in levels of CCL2 protein detected in serum from pigs infected with this isolate. An increase in overall chemotaxis active compounds in defibrinated plasma samples from Benin 97/1 infected pigs was observed at 3 days post-infection (dpi) and a decrease by 7 dpi as measured by chemotaxis assay using normal pig leucocytes in vitro. Increased levels of CXCL10 may either contribute to the activation of lymphocyte priming toward the Th1 phenotype or induction of T lymphocyte apoptosis. Increased levels of CCL2, a chemoattractant for macrophages, may result in increased recruitment of monocytes from bone marrow thus increasing the pool of cells susceptible to infection. 相似文献
15.
Fekadu Marame Chemeda Fininsa Harjit Singh Lemma Dessalegne Anhild Andersson Roland Sigvald 《Euphytica》2010,172(1):77-91
The productivity and marketable quality of hot pepper (Capsicum annuum var. annuum L.) are low in tropical regions mainly due to virus infections and lack of effective virus management strategies. The absence
of effective virus management strategies could be attributed to lack of information on virus vectors and host resistance.
Parental (P1 and P2) and progeny (F1, B1, B2 and F2) generations of five hot pepper crosses were grown in Ethiopia at three sites (Bako, Hawasa and Melkasa) to monitor number
and species of potential aphid vectors, disease incidence levels with regards to natural infections by Potato virus Y (PVY) and Ethiopian pepper mottle virus (EPMV) complex, and to determine genetic tolerance of the crop to the viruses. Disease incidence was assessed before the
flowering stage of the crop plants using visible disease symptoms due to infections by PVY and EPMV. The serological tests
revealed presence of symptomless genotypes of the crop to the virus infections. Aphid species potentially transmitting the
viruses, such as Acyrthosiphon pisum (Harris), Aphis fabae (Scopoli), and Myzus persicae (Sulzer), were identified from specimens caught by yellow water traps. The highest number of aphids from yellow water traps
was recorded at a dense foliage growth stage of the crop at Melkasa. Highly significant variation was observed among generations
of the five crosses in response to infections by PVY and EPMV complex. The most susceptible parents had the levels of disease
incidences ranging from 80 to 90%, whereas their progenies had only below 30% incidence levels. The most tolerant parent remained
symptomless to the natural infections of PVY- and EPMV-complex. Incidence levels in progenies of a cross from the most susceptible
and tolerant parents remained below 20%. Based on serological test, the proportion of PVY-positive plants ranged from 0 to
75% and of EPMV-positive plants from 0 to 25%, with 0 to 17% co-infection by the two viruses. Availability of virus sources
in the vicinity, efficiency of aphids in vectoring, weather conditions during the growth period, genetic tolerance and the
growth stage of the crop affected natural infection by PVY- and EPMV-complex. Exploitation of the genetic potential of introduced
elite genotypes and their progenies along with breeding elite local cultivars for resistance and excluding aphid vectors at
young (seedling) stage of the crop plants could be helpful for minimizing losses in yield and quality of hot pepper due to
infections by PVY- and EPMV-complex. 相似文献
16.
Parjeet Singh Aulakh Major S. Dhaliwal Salesh Kumar Jindal Roland Schafleitner Kuldeep Singh 《Plant Breeding》2016,135(4):531-535
Most of the hybrid seed in chilli are produced manually, but the use of male sterility (MS) can reduce the cost of hybrid seed production. MS‐12, a nuclear male‐sterile (NMS) line developed at Punjab Agricultural University, Ludhiana (India), has been utilized to develop commercial F1 hybrids. A recessive gene, designated as ms10, governs MS in MS‐12. Due to recessive gene control, development of new NMS lines incorporating ms10 gene is tedious and time‐consuming. We identified SSR markers AVRDC‐PP12 and AVRDC_MD997* linked to the ms10 gene. A total of 558 primer pairs were screened following bulked segregant analysis (BSA). Linkage analysis in 210 F2 plants indicated that the two SSR markers were linked to the ms10 gene and the marker AVRDC‐PP12 was closest to the gene at 7.2 cM distance. The marker was mapped to chromosome 1 at genome position 175 694 513 to 175 694 644. Until more closely linked markers are developed, the marker AVRDC‐PP12 would facilitate transfer of ms10 gene through marker‐assisted selection (MAS). Fine mapping would lead to cloning of the ms10 gene. 相似文献
17.
Effects of Land‐Related Policies on Land Development during a Real Estate Boom and a Recession 下载免费PDF全文
Seong‐Hoon Cho Seung Gyu Kim Roland K. Roberts Dayton M. Lambert Taeyoung Kim 《Growth and change》2015,46(2):218-232
Our research evaluates and compares the effects of three land‐related policies on land development in a sprawling metropolitan area during a real estate boom and a recession. Our findings suggest that during a real estate boom 1) the urban growth boundary (UGB) serves its purpose of attracting urban development inside the given boundary during a boom while its effectiveness diminishes with increased development pressure from lower‐valued land outside of the UGB during a recession period, 2) the agricultural zone works well for restraining new development during a boom period while agriculture zoned parcels are more likely developed during a recession period, and 3) an increase in the land‐value tax bill increases the incentive for development during a recession period while higher tax bills do not affect development during a boom period. In anticipation of a re‐emergence of urban sprawl with the recovery of the real estate market, our findings imply that land planners and others concerned with sprawling development should pay more attention to development in sprawl‐prone areas during recession periods. 相似文献
18.
European natural and semi-natural grassland form reservoirs of genetic resources containing highly adapted and variable ecotype
populations of forage plants. Variation within these reservoirs is stimulated by variation in natural and anthropogenic site-related
factors. Changes in agricultural practices lead to the loss of many characteristic habitats. In order to preserve resources
for breeding, targeted conservation strategies for germplasm in gene banks (ex-situ) or on site (in-situ) are needed. In order
to define site-related criteria for the potential of habitats to preserve valuable resources for breeding and conservation,
38 different habitats across Switzerland were selected to collect Festuca pratensis Huds. and Lolium multiflorum Lam. ecotype populations. Phenotypic variation and population differentiation of 60 single plants were evaluated in a field
experiment using 16 morpho-physiological traits. For F. pratensis, ecotype populations and cultivars were clearly separated and there was a significant correlation between diversity of morphological
traits and geographic location of sampling sites. For L.
multiflorum no clear separation of ecotype populations and cultivars was observed suggesting gene flow from adjacent temporary leys into
permanent grassland. Several ecotype populations were superior to cultivars in important traits such as early heading or resistance
to winter damage, indicating the importance of natural habitats as a reservoir of genetic resources for breeding. In conclusion,
maintenance of permanent grassland in contrasting environments appears to be a promising strategy for preserving valuable
genetic variation of forage grasses.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Peter Hanson Roland Schafleitner Shu-Mei Huang Chee-Wee Tan Dolores Ledesma Ray-Yu Yang 《Euphytica》2014,200(3):441-454
Consumption of flavonoids found in fruits and vegetables is linked to beneficial health outcomes. Tomato is among the most widely consumed and economically important vegetables worldwide and improvement of the nutrient content could lead to significant health benefits. Rutin, (quercetin-3-rutinoside), the main flavonol in tomato fruit, is confined to the peel. Rutin synthesis is limited by low expression of chalcone isomerase, the enzyme catalyzing the conversion of naringenin chalcone to naringenin quercetin. The wild tomato species Solanum habrochaites is a major source of new alleles to improve cultivated tomato (Solanum lycopersicum). AVRDC—The World Vegetable Center identified introgression line (IL) LA3984 containing a segment of S. habrochaites on chromosome 5 expressing high levels of rutin in full red ripe fruit. An AVRDC high rutin tomato line evaluated for 2 years and two seasons in Taiwan produced mean rutin content about four- to five-fold greater than the mean of all entries and about 11–12 times higher than the commercial fresh market and processing tomato cultivars. The quantitative trait locus (QTL) conditioning high rutin content was mapped to a 0.42 Mb segment on chromosome 5 flanked by markers c2_At3g55120/TaqI and ch05-4.883/ApaLI. Marker c2_Atg55120 overlaps with the chalcone-flavonone isomerase gene Solyc05g10320, and a second chalcone-flavonone isomerase gene is located 3,000 bp upstream from c2_At3g551220. Results of this project will facilitate breeding of high flavonoid tomato lines. 相似文献
20.
Stefanie Raabe Jörg Müller Michael Manthey Oliver Dürhammer Ulrich Teuber Axel Göttlein Bernhard Förster Roland Brandl Claus Bässler 《Forest Ecology and Management》2010
Understanding the major drivers of diversity in forests is crucial for ecologists, conservationists, and particularly forest managers. In most forested habitats, bryophytes are diverse and important primary producers. Here we report the first study of the relative importance of regional macroclimate as compared to local variables on abundance, species richness, and community composition of bryophytes growing in soil and in dead wood in a mountain temperate forest. Using PCA axes, we built predictor sets for macroclimate, microclimate, soil attributes, and dead wood availability. The explanatory power of each set was tested using variance partitioning. Abundance and species richness of soil bryophytes was best explained by microclimate, whereas the community composition did not distinctively differ between the environmental sets. In contrast, dead wood bryophyte abundance, species richness, and community composition was clearly driven by macroclimate. Among the single axes, the component represented best by soil moisture was the main driver for soil bryophyte abundance. In contrast, dead wood bryophyte abundance was mostly affected by components correlated with minimum global radiation and minimum temperatures as well as by the component represented by dead wood. The component represented by canopy openness was superior in explaining the community composition of both soil and dead wood bryophytes. We conclude that (1) dead wood amounts should be increased in closed stands to act as a buffer during climate changes, and (2) open canopy, which provides important habitats for soil-inhabiting bryophytes, should be provided by management with slow reforestation after natural or logging openings. 相似文献