全文获取类型
收费全文 | 99篇 |
免费 | 4篇 |
专业分类
林业 | 12篇 |
农学 | 6篇 |
12篇 | |
综合类 | 7篇 |
农作物 | 2篇 |
水产渔业 | 15篇 |
畜牧兽医 | 41篇 |
园艺 | 1篇 |
植物保护 | 7篇 |
出版年
2022年 | 1篇 |
2021年 | 7篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 1篇 |
2016年 | 5篇 |
2015年 | 5篇 |
2014年 | 3篇 |
2013年 | 3篇 |
2012年 | 8篇 |
2011年 | 6篇 |
2010年 | 6篇 |
2009年 | 2篇 |
2008年 | 7篇 |
2007年 | 7篇 |
2006年 | 6篇 |
2005年 | 6篇 |
2004年 | 3篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有103条查询结果,搜索用时 31 毫秒
21.
22.
Sijun Zheng Betty Henken Willem Wietsma Eri Sofiari Evert Jacobsen Frans A. Krens Chris Kik 《Euphytica》2000,114(1):77-85
The beet armyworm (Spodoptera exigua Hübner)is the most important pest in tropical Alliumcultivations. All shallot (Allium cepa L. group Aggregatum) cultivars are susceptible to this pest. Therefore accessions from three wild Alliumspecies, namely A. galanthum Kar. et Kir., A. fistulosum L. and A. royleiStearn, next to A. cepa L. were used to screen for resistance. First of all, a reliable bio-assay had to be developed. To this end transparent plastic
cages with in total 5 plants of one accession per cage were placed on per lite in a heated greenhouse. Five 3-day old larvae
were inoculated on each plant. Eight days after inoculation the number of surviving larvae per cage and the mean fresh weightper
larva was determined. The lowest larval survival (36%) was found on A. roylei. This was not, however, significantly different from other Allium accessions. Significant differences were found in the fresh weight per larva fed on different Allium accessions. The larvae survived on A. roylei had a very low fresh weight (10.3 mg per larva), while those on an accession of A. fistulosum had the highest fresh weight (45.1 mg per larva). The larval fresh weight on A. roylei was lower than all the other accessions except from the tropical shallot cultivar Bawang Bali. To check whether or not a
toxic compound was involved in the resistance present in A. roylei, tenaccessions from four Allium species were screened. Five 3-day old larvae were inoculated on regularly replaced leaf material of each accession ofAllium species. No significant differences were found in mean fresh weight per larva and mean survival of larvae among different
accessions. There were also no significant differences in pupal weight and developmental time. All larvae became pupae 10
days after inoculation. The data indicate that there is no toxic compound present in A. roylei. These results are underlined by the observation in the greenhouse bio-assay that A. roylei plants were equally damaged by the beet armyworm compared to otherAllium species. The results obtained so far therefore suggest that introduction of resistance to S. exigua via the exploitation of variation for resistance to the beet armyworm in A. roylei is unclear and that genetic engineering using Cry sequences could provide a way forward.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
23.
Takashi?Nakatsuka Misa?Saito Yuka?Sato-Ushiku Eri?Yamada Takashi?Nakasato Nobue?Hoshi Kazumichi?Fujiwara Takashi?Hikage Masahiro?NishiharaEmail author 《Euphytica》2012,184(3):335-344
We developed molecular markers for discrimination of white and blue flower color in Japanese gentian plants. White-flowered
gentians can be classified into two types, based on genetic and physiological features. One type includes four allelic variations
(gtmyb3-1, gtmyb3-2, gtmyb3-3, and gtmyb3-4) of an anthocyanin biosynthetic regulator gene (GtMYB3), distinguished by three PCR-based molecular markers. The other type contains a newly identified inactive allele (ans1) of the anthocyanidin synthase (ANS) gene with a premature stop codon generated from a 4-bp deletion in the second exon. The ans1 allele was distinguished from the active ANS allele by a cleaved amplified polymorphism sequence (CAPS) marker. The genotypes of 12 white-flowered gentian cultivars/lines
could be identified and classified as either ans1 or gtmyb3 using these four molecular markers. No white-flowered gentians contained ans1 and gtmyb3 alleles simultaneously. The mutated ANS gene co-segregated with white flower color in an F2 population, demonstrating that the CAPS marker is useful to discriminate between white and blue flowers in gentian. Markers
to discriminate flower color in Japanese gentian will be useful for early selection of progeny and for breeding management. 相似文献
24.
Kitai S Shimizu A Kawano J Sato E Nakano C Kitagawa H Fujio K Matsumura K Yasuda R Inamoto T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(3):269-274
A total of 444 samples of raw chicken meat (thighs, breasts, wings, livers, gizzards, hearts and ovaries) that retailed at 145 different supermarkets in 47 prefectures in Japan were examined for contamination with Staphylococcus aureus in association with its enterotoxigenicity. S. aureus was isolated from 292 (65.8%) of the samples, and from 131 of the 145 supermarkets. There was no significant difference in the detection rate of S. aureus according to the type of meat examined. About 80% of 714 isolates belonged to the poultry (57.1%) and human biotypes (22.1%). Seventy-eight (21.7%) of 360 isolates were enterotoxigenic and isolated from 78 samples in 53 supermarkets in 31 prefectures. Staphylococcal enterotoxins (SEs) produced were SEB (50 isolates), SEA (14), SEC (8), SED (2), SEA+SEB (2), and SEA+SEC (2). Most of the enterotoxigenic isolates belonged to the human and poultry biotypes, coagulase type VII, VIII or IV, and were lysed by phages of group III. Identical SE types, biotypes, coagulase types and pulsed-field gel electrophoresis (PFGE) patterns were shown in isolates from different types of meat at the same supermarket and from samples taken from different supermarkets in the same prefectures or in isolates from samples obtained from several different prefectures. Among the 50 SEB-producing isolates, 27 yielded three similar PFGE patterns that differed by only a few fragments, suggesting that they were closely related genetically. The three patterns were found in isolates of samples that retailed at 17 supermarkets in 11 prefectures, indicating that they may be disseminated among raw chicken meat in Japan. 相似文献
25.
Itagaki T Kikawa M Terasaki K Shibahara T Fukuda K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(11):1115-1118
Nucleotide sequences of ribosomal internal transcribed spacer (ITS1) and mitochondrial NADH dehydrogenase I (NDI) gene were analyzed to genetically characterize aspermic Fasciola forms in Korea. From the difference in ITS1 sequences, Korean flukes were divided into 3 haplotypes represented by Kor1, Kor2 and Kor1/2, which had nucleotides identical to F. hepatica, F. gigantica and those overlapped between the two species, respectively. NDI sequences also showed that Korean flukes could be classified into 3 distinct haplotypes (Kor1: F. hepatica-type, Kor2a and Kor2b: F. gigantica-type). The sequences of Kor1 and Kor2a were 100% identical to those of the haplotypes Fsp1and Fsp2, respectively, which are major Fasciola forms in Japan. These findings strongly suggest that aspermic Fasciola forms in Korea and Japan originated from same ancestors and have recently spread throughout both countries. 相似文献
26.
27.
Ohba Y Takasu M Nishii N Takeda E Maeda S Kunieda T Kitagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(3):297-299
Using a DNA-based diagnostic test for factor XI deficiency in Japanese black cattle, we surveyed 123 cattle (42 sires and 81 dams) in Gifu and Hyogo prefectures, and calculated gene frequencies. In sires, we drew up the pedigree network of the cattle with the factor XI deficiency. Results showed that the mutated allele of factor XI deficiency was retroactive in at least 6 or more generations of sires. Frequencies of the mutant gene were higher at 26.4% in total, and at 33.3% in sires. All 7 cattle with the homozygote of mutated allele were clinically normal, and showed no bleeding episodes. The mutated allele of factor XI deficiency might be widespread among Japanese black cattle. 相似文献
28.
The chemical conversion of red pine sulfuric acid lignin (Klason lignin) (SAL) as an acid hydrolysis lignin sample to water-soluble arylsulfonates of lignin derivation (i.e., phenolized SAL) was investigated. Treatment of phenolized SAL with chlorosulfonic acid followed by alkali hydrolysis gave water-soluble sulfonated products with a sulfonic acid group on their aromatic nuclei quantitatively. The products possess 2.0 SO3Na/C9 C6. In contrast, the content of sulfuric acid group in sulfonated SAL was only 0.33C9. Chlorosulfonation of 1-guaiacyl-l-p-hydroxyphenylethane as a phenolized guaiacyl lignin model compound revealed that the sulfonyl chloride group was introduced at thepara position of an aromatic methoxyl group, theortho position of a phenolic hydroxyl group, or both. 相似文献
29.
Shoko Fukuda Tetsuya Kobayashi Ian D. Robertson Fukiko Oshima Eri Fukazawa Yuko Nakano Shin Ono Donald E. Thrall 《Veterinary radiology & ultrasound》2014,55(4):374-379
The purpose of this retrospective study was to describe pre‐ and postcontrast computed tomographic (CT) characteristics of confirmed nonparenchymal hemangiosarcoma in a group of dogs. Medical records were searched during the period of July 2003 and October 2011 and dogs with histologically confirmed nonparenchymal hemangiosarcoma and pre‐ and postcontrast CT images were recruited. Two observers recorded a consensus opinion for the following CT characteristics for each dog: largest transverse tumor diameter, number of masses, general tumor shape, character of the tumor margin, precontrast appearance, presence of dystrophic calcification, presence of postcontrast enhancement, pattern of postcontrast enhancement, presence of regional lymphadenopathy, and presence of associated cavitary fluid. A total of 17 dogs met inclusion criteria. Tumors were located in the nasal cavity, muscle, mandible, mesentery, subcutaneous tissue, and retroperitoneal space. Computed tomographic features of nonparenchymal hemangiosarcoma were similar to those of other soft tissue sarcomas, with most tumors being heterogeneous in precontrast images, invasive into adjacent tissue, and heterogeneously contrast enhancing. One unexpected finding was the presence of intense foci of contrast enhancement in 13 of the 17 tumors (76%). This appearance, which is not typical of other soft tissue sarcomas, was consistent with contrast medium residing in vascular channels. Findings indicated that there were no unique distinguishing CT characteristics for nonparenchymal hemangiosarcoma in dogs; however, the presence of highly attenuating foci of contrast enhancement may warrant further investigation in prospective diagnostic sensitivity and treatment outcome studies. 相似文献
30.
The use of direct thermal desorption-gas chromatography-mass spectrometry (DTD-GC-MS) and DTD-GC-flame ionization detection (DTD-GC-FID) for characterization of hop essential oils is described. Four hop varieties (Nugget, Galena, Willamette, and Cluster) from the Yakima valley (Yakima, WA) 1998 harvest were analyzed by DTD-GC-MS and DTD-GC-FID methodology. Approximately 1 g of hops was needed for the analysis. Hop samples were prepared for GC-MS and/or GC-FID profiling in approximately 20 min. More than 100 volatile compounds have been identified and quantified for each hop variety. The results were found to be in good agreement with conventional steam distillation-extraction (SDE) data. A calibration curve for determination of essential oil content in hops by DTD-GC-FID has been generated. Quantitation of hop oil content by DTD-GC-FID was shown to be in good agreement with conventional SDE data. The recovery of key oil components valuable for varietal identification was demonstrated to be highly reproducible and characteristic of each variety analyzed when DTD-GC-FID was used for analysis. 相似文献