全文获取类型
收费全文 | 49篇 |
免费 | 1篇 |
专业分类
林业 | 2篇 |
农学 | 1篇 |
1篇 | |
综合类 | 4篇 |
水产渔业 | 6篇 |
畜牧兽医 | 33篇 |
植物保护 | 3篇 |
出版年
2021年 | 1篇 |
2013年 | 1篇 |
2012年 | 1篇 |
2011年 | 3篇 |
2008年 | 3篇 |
2007年 | 1篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2001年 | 2篇 |
2000年 | 8篇 |
1999年 | 8篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1992年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1933年 | 1篇 |
1930年 | 1篇 |
排序方式: 共有50条查询结果,搜索用时 187 毫秒
1.
2.
Garth N. Foster Brian H. Nelson David T. Bilton Derek A. Lott Robert Merritt Richard S. Weyl Michael D. Eyre 《水产资源保护:海洋与淡水生态系统》1992,2(2):185-208
1. Modern records of 165 species of wetland beetle (Haliplidae, Hygrobiidae, Noteridae, Dytiscidae, Gyrinidae, Georissidae, Hydrochidae, Helophoridae, Hydrophilidae, Hydraenidae, Scirtidae, Dryopidae, Elmidae, Chrysomelidae, Curculionidae) were assembled for analysis. 2. Two hundred and eighty nine modern lists of seven or more species of water beetle from sites in Ireland were subjected to multivariate analysis. 3. Ten assemblage types were identified using TWINSPAN. Habitats typical of these assemblages are: A. deep rivers; B. rivers with riffles; C. puddles; D. canals and lakes with rich vegetation; E. ponds and ditches; F. turloughs; G. natural, minerotrophic fens; H. base-flushed cutover bogs; I. peat bogs; J. montane flushes. The distribution of these types is discussed. 4. Ordination of site data by DECORANA indicated that the important environmental variables dictating water beetle assemblage type in Ireland were: flow; water permanence; exposure; type of substratum. Acidity could not be isolated as a determinant, except within the analysis of assemblage types conducted using TWINSPAN. DECORANA isolated one brackish site as an outlier but salinity was not otherwise a major factor, probably because few brackish sites were included in the analysis. 5. The number of modern records for each species was used to provide a provisional set of species-quality scores. A simple rationale was devised to weight these scores in favour of relict species and against elusive species, species with short-lived adults and species primarily associated with man-made habitats. 6. The average species-quality score per site and the number of species recorded were used to rank sites within each TWINSPAN end-group. The most diverse sites with the highest quality were some turloughs, rich fens and base-flushed peat cutting complexes. Some montane lakes and flushes with relatively few species had high species-quality scores. 相似文献
3.
Sreedharan J Blair IP Tripathi VB Hu X Vance C Rogelj B Ackerley S Durnall JC Williams KL Buratti E Baralle F de Belleroche J Mitchell JD Leigh PN Al-Chalabi A Miller CC Nicholson G Shaw CE 《Science (New York, N.Y.)》2008,319(5870):1668-1672
Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disorder characterized pathologically by ubiquitinated TAR DNA binding protein (TDP-43) inclusions. The function of TDP-43 in the nervous system is uncertain, and a mechanistic role in neurodegeneration remains speculative. We identified neighboring mutations in a highly conserved region of TARDBP in sporadic and familial ALS cases. TARDBPM337V segregated with disease within one kindred and a genome-wide scan confirmed that linkage was restricted to chromosome 1p36, which contains the TARDBP locus. Mutant forms of TDP-43 fragmented in vitro more readily than wild type and, in vivo, caused neural apoptosis and developmental delay in the chick embryo. Our evidence suggests a pathophysiological link between TDP-43 and ALS. 相似文献
4.
5.
6.
TA Abdulkareem SAM Al‐Sharifi MA Ishak SM Eidan MA Alnimr CW Passavant JR Branen RG Sasser 《Reproduction in domestic animals》2011,46(3):455-462
This study was undertaken to detect pregnancy in Iraqi riverine buffalo (Bubalus bubalis) using three different methods (rectal palpation, plasma progesterone concentration and detection of the presence of pregnancy‐specific protein B (PSPB) with the BioPRYN® enzyme‐linked immunosorbent assay (ELISA) test. The aim of the study was to identify the most sensitive, early and accurate method for detecting pregnancy. Twenty‐two female riverine buffalo that were 6.0 ± 0.93 years old were used. Four blood samples per buffalo were taken via jugular venipuncture at days 22–24, 32–34, 42–44 and 58–61 post‐mating (PM) to measure the progesterone concentration (ng/ml) and to detect the presence of plasma PSPB. The rectal palpation method was employed to evaluate all buffalo on days 42–44 and 58–61 PM. The BioPRYN® test differed (p < 0.01) from the other tests with earlier accuracy for detecting pregnant and non‐pregnant buffalo. Eighty‐eight percent of pregnant and 76.9% of non‐pregnant buffalo were distinguished early (days 22–24 PM) using BioPRYN® and plasma PSPB‐ELISA level (2.09 ± 0.12 ng/ml) in relation to 66.7% and 53.9% detected using the progesterone assay at similar days (4.30 ± 0.40 ng/ml). In conclusion, these results described, for the first time, the early and accurate pregnancy detection of water riverine buffalo using BioPRYN® technology and provided the plasma levels of PSPB using an ELISA test. These findings will improve the reproductive and productive efficiency of Iraqi riverine buffalo by adapting the recent management and reproductive strategies in Iraq and in the world. 相似文献
7.
Contribution to the taxonomy of the turkey coryza agent: cellular fatty acid analysis of the bacterium 总被引:5,自引:0,他引:5
Gas-liquid chromatography was used to analyze bacterial cellular fatty acids to elucidate the relatedness of the turkey coryza (TC) bacterium to Alcaligenes spp., Bordetella spp., and other gram-negative bacteria. The results indicated that the TC bacterium is not closely related to Alcaligenes faecalis or any of the reference strains of Alcaligenes and Bordetella studied. Most urease-positive bacterial isolates obtained from the upper respiratory tract of turkeys were identified as Bordetella bronchiseptica. It is suggested that Bordetella avium is a suitable designation for the TC bacterium formally called Bordetella-"like" and A. faecalis type I. It is also suggested that the nonpathogenic bacterium previously identified as type II A. faecalis be designated B. avium-like until further taxonomic studies are available. Furthermore, it is proposed that the term turkey coryza be used to refer to the disease induced by this bacterium. 相似文献
8.
9.
Twenty-year-old overstocked naturally regenerated yellow birch (Betula alleghaniensis Britton) were thinned near Thessalon, Ontario. Treatments consisted of either a control, or the removal of all competing trees at 1, 2, 3, or 4 m around the boles of the crop trees. The size of the openings created around the crop tree crowns was found to be more strongly correlated to diameter, clear bole length, and crown increment than the removal of competing trees using fixed distance from the stem. Crop trees responded well to thinning. Five-year diameter increment and crown diameter growth were positively correlated to size of the opening created around the crop tree crown. However, the relationship between height growth and size of canopy opening was weak. Clear bole length was found to be negatively correlated to the size of canopy opening. Few epicormic sprouts developed on the stems when all competing trees were removed at 1, 2, or 3 m around the crop tree boles. However, release at 4 m greatly increased the number and size of epicormic sprouts. Providing about a 15-m2 opening around the crop tree crown, corresponding to approximately a 3-m removal of competing trees around the bole, provided a good balance between diameter increment and stem quality maintenance. 相似文献
10.
Boutet S Lomb L Williams GJ Barends TR Aquila A Doak RB Weierstall U DePonte DP Steinbrener J Shoeman RL Messerschmidt M Barty A White TA Kassemeyer S Kirian RA Seibert MM Montanez PA Kenney C Herbst R Hart P Pines J Haller G Gruner SM Philipp HT Tate MW Hromalik M Koerner LJ van Bakel N Morse J Ghonsalves W Arnlund D Bogan MJ Caleman C Fromme R Hampton CY Hunter MS Johansson LC Katona G Kupitz C Liang M Martin AV Nass K Redecke L Stellato F Timneanu N Wang D Zatsepin NA Schafer D Defever J 《Science (New York, N.Y.)》2012,337(6092):362-364
Structure determination of proteins and other macromolecules has historically required the growth of high-quality crystals sufficiently large to diffract x-rays efficiently while withstanding radiation damage. We applied serial femtosecond crystallography (SFX) using an x-ray free-electron laser (XFEL) to obtain high-resolution structural information from microcrystals (less than 1 micrometer by 1 micrometer by 3 micrometers) of the well-characterized model protein lysozyme. The agreement with synchrotron data demonstrates the immediate relevance of SFX for analyzing the structure of the large group of difficult-to-crystallize molecules. 相似文献