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291.
Brachiaria ruziziensis is a sexual diploid tropical grass species of wide adaptation and good forage quality. Pachytene chromosomes were studied in morphological detail and all nine chromosomes were identified by their length, centromere position, and size and distribution of chromomeres. The idiogram prepared for the first time in this species consists of four median and five submedian chromosomes. 相似文献
292.
Rafael Reyno Rafael Narancio Pablo Speranza Javier Do Canto Beatriz López-Carro Pablo Hernández Juan Burgue?o Daniel Real Marco Dalla Rizza 《Genetic Resources and Crop Evolution》2012,59(8):1823-1832
Paspalum notatum is a subtropical grass present throughout America, and one of the main constituents of the natural grasslands in Uruguay. An apomictic autotetraploid (2n?=?4x?=?40) is the most frequent cytotype. The occurrence of sexual diploids (2n?=?2x?=?20) has also been reported as well as the occasional presence of apomictic triploids and pentaploids in Argentina. In this study, ISSR (inter simple sequence repeats) molecular markers were used to analyze the genetic variability of 210 P. notatum individuals from a collection from Uruguay. Cytometric analyses and chromosome counts were used to assess the ploidy level of the individuals. All plants from Uruguay analyzed were tetraploid. Intra- and inter-population variability was found both in genomic DNA content and at the genotypic level. Several multilocus genotypes were shared among individuals within populations and among populations over moderate geographical ranges, at the same time, very dissimilar genotypes were found within the same population. Part of the genetic variance among populations can be explained by a broader scale geographic structure which is partly coincident with the traditionally recognized grassland management regions. In spite of the apparently high degree of genetic admixture within populations, groups of related genotypes seem to follow a broader geographical structure in the area under study. These results suggest that an efficient collection strategy for this apomictically reproducing species should include carefully planned intra- and inter-population sampling. A broader scale regional sampling strategy should also be considered although further studies will be required to define genetic structure at this level. 相似文献
293.
Sun Hee Do Il-Hwa Hong Jin-Kyu Park Ae-Ri Ji Tae-Hwan Kim Dong-Mi Kwak Kyu-Shik Jeong 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(2):169-171
We describe 2 cases of malignant fibrous histiocytomas (MFHs) that spontaneously developed in young pet dogs. To classify these tumors, we applied a panel of antibodies (vimentin, desmin, α-SMA, and ED1) and Azan staining for collagen. The MFHs were most consistent with osteoclast-like giant and inflammatory cell types. The first case had positive staining for ED1 and vimentin, and given the osteoclast-like giant cells, calcification sites accompanying peripheral giant cell infiltrates. The latter case, the inflammatory cell type, exhibited a storiform-pleomorphic variant of neoplastic cells, including an ossifying matrix. MFHs are among the most highly aggressive tumors occurring in soft tissue sarcomas in elderly dogs; however, MFHs have been poorly studied from a diagnostic point of view. Herein, we describe the histologic and immunohistologic features of MFHs in detail, thus classifying the subtypes of these tumors. 相似文献
294.
Aleutian disease (AD), caused by the Aleutian mink disease virus (AMDV), is a major health concern that results in global economic losses to the mink industry. The unsatisfactory outcome of the culling strategy, immunoprophylaxis, and medical treatment in controlling AD have urged mink farmers to select AD resilient mink based on several detection tests, including enzyme-linked immunosorbent assay (ELISA), counterimmunoelectrophoresis (CIEP), and iodine agglutination test (IAT). However, the genetic analysis of these AD tests and their correlations with pelt quality, reproductive performance, packed-cell volume (PCV), and harvest length (HL) have not been investigated. In this study, data on 5,824 mink were used to estimate the genetic and phenotypic parameters of four AD tests, including two systems of ELISA, CIEP, and IAT, and their genetic and phenotypic correlations with two pelt quality, five female reproductive performance, PCV, and HL traits. Significances (P < 0.05) of fixed effects (sex, year, dam age, and color type), covariates (age at harvest and blood sampling), and random effects (additive genetic, permanent environmental, and maternal effects) were determined under univariate models using ASReml 4.1 software. The genetic and phenotypic parameters for all traits were estimated under bivariate models using ASReml 4.1 software. Estimated heritabilities (±SE) were 0.39 ± 0.06, 0.61 ± 0.07, 0.11 ± 0.07, and 0.26 ± 0.05 for AMDV antigen-based ELISA (ELISA-G), AMDV capsid protein-based ELISA, CIEP, and IAT, respectively. The ELISA-G also showed a moderate repeatability (0.58 ± 0.04) and had significant negative genetic correlations (±SE) with reproductive performance traits (from −0.41 ± 0.16 to −0.49 ± 0.12), PCV (−0.53 ± 0.09), and HL (−0.45 ± 0.16). These results indicated that ELISA-G had the potential to be applied as an indicator trait for genetic selection of AD resilient mink in AD endemic ranches and therefore help mink farmers to reduce the adverse effects caused by AD. 相似文献
295.
Patricia Davenport Viola Lorenz Zhi-Jian Liu Henry A. Feldman Jorge Canas Emily Nolton Chiara-Aiyleen Badur Thi Minh-Thi Do Martha Sola-Visner 《Journal of veterinary diagnostic investigation》2021,33(5):913
The immature platelet fraction (IPF) is a measure of newly released platelets, which has been used as a marker of platelet production in multiple human studies but is not widely available in multispecies analyzers. We developed gates to measure the IPF in diluted and undiluted murine blood samples on the Sysmex XN-1000V multispecies hematology analyzer. IPF gates were created using undiluted and diluted (1/10) blood samples obtained from adult and newborn (postnatal day 10, P10) C57BL/6J wild-type (WT) mice, and from 3 murine models of thrombocytopenia: c-MPL−/− mice, which lack the thrombopoietin receptor (hyporegenerative); antibody-mediated thrombocytopenia; and acute inflammation-induced thrombocytopenia. P10 mice were chosen because, at their size, we could consistently obtain (by terminal phlebotomy) the blood volume needed to run an undiluted sample. The undiluted blood IPF gate successfully differentiated between mechanisms of thrombocytopenia in both adult and P10 mice. For diluted samples, 2 IPF gates were generated: a thrombocytopenic (T) gate, which performed well in samples with platelet counts (PCs) <800 × 109/L in adult mice and <500 × 109/L in newborn mice, and a non-thrombocytopenic (NT) gate, which performed well in samples with PCs above these thresholds. PCs and IPFs measured in diluted blood using these gates agreed well with those measured in undiluted blood and had good reproducibility. These diluted gates allow for the accurate measurement of PCs and IPFs in small (10 µL) blood volumes, which can be obtained easily from adult and newborn mice as small as P1 to assess platelet production serially. 相似文献
296.
Adsorption of methylene blue from aqueous solutionsonto unexpanded and expanded perlite samples activatedby H2SO4 and NaCl solutions has beeninvestigated, to assess the possibility of usingperlite for removing cationic dyes from aqueoussolutions. The effects of pH and temperature of dyesolution on the adsorption capacities have beenevaluated. The experimental data were correlatedreasonably well by the Langmuir adsorption isothermand the isotherm parameters (Q m and K) have beencalculated. The removal efficiency (P) anddimensionless separation factor (R) have shown thatperlite can be used for removal of methylene blue fromaqueous solutions, but unexpanded perlite is more effective. 相似文献
297.
Quoc Thinh Nguyen Caroline Douny Minh Phu Tran Francois Brose Phuong Thanh Nguyen Do Thi Thanh Huong Patrick Kestemont Marie‐Louise Scippo 《Aquaculture Research》2019,50(1):247-255
To develop an easy and reliable method for detecting pesticides and their residues in the Mekong Delta, a GC‐MS analytical method was developed and validated according to European guidelines (SANTE/11945/2015) for the determination of residues of three pesticides (quinalphos, trifluralin and dichlorvos) in water. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.002 and 0.007 μg/L, respectively, for quinalphos and trifluralin, and 0.016 and 0.053 μg/L, respectively, for dichlorvos and quinalphos. The repeatability, the within‐laboratory reproducibility as well as the trueness met the European criteria. The recovery rate ranged between 72% (for dichlorvos and quinalphos) and 82% (for trifluralin). The developed method was then applied for the analysis of 33 water samples, collected in April 2013, at the beginning of the rainy season in the Mekong Delta in Vietnam. Thirteen samples were from rice field, 10 were collected from cat fish ponds and from red tilapia cages. Results showed that only 9% of total water samples analysed contained residues of pesticides, but only in water from rice fish systems. From the 13 samples taken in these systems, quinalphos was detected in three samples. The other two pesticides were not detected. A comparison between analytical results obtained from GC‐MS and an alternative method, that is GC‐ECD indicated that GC‐ECD is less sensitive than GC‐MS, with LOQ ranging from 0.37 to 1.18 (depending on the pesticide). However, for samples with concentrations above these LOQ, no significant difference was observed between the results obtained from the two analytical methodologies. 相似文献
298.
Do Yoon Hyun MyeongWon Oh Yu-Mi Choi Sukyeung Lee Myung-Chul Lee Sejong Oh 《Journal of Crop Science and Biotechnology》2017,20(1):21-27
Direct-seeding cultivation of rice is increasing in Asia instead of transplanting system, because of its lower cost and operational simplicity. Low-temperature germinability (LTG) and anaerobic germinability (AG) are important characters for breeding of varieties for wide-spread adaptation of direct-seeding cultivation in rice. This study was performed to evaluate LTG and AG of seven rice varieties and identify varieties with strong germinability on both low-temperature and anaerobic conditions. The mean germination rate and germination vigor of seven varieties were 51.7% and 6.0 under low-temperature condition, respectively. Among these varieties, Cheongcheongjinmi and Hwanggeumnodeul had the highest germination rate of 80%, indicating that Cheongcheongjinmi and Hwanggeumnodeul have a good LTG. In anaerobic conditions, the germination rate and coleoptile length for all varieties were 47.6% and 3.2 cm, respectively. Of them, the highest germination rate and coleoptile length were observed in Subo and Hopum, respectively, suggesting that these two varieties are tolerant to anaerobic during germination stage. Molecular evaluation by SDS-PAGE revealed that the protein patterns differed at 50 kDa, 40 kDa, and 22 kDa between low-temperature and anaerobic conditions. Varieties identified as good LTG or AG in this study may be used for developing new direct-seeding rice cultivars through pyramiding these traits in the breeding program. 相似文献
299.