全文获取类型
收费全文 | 72篇 |
免费 | 0篇 |
专业分类
林业 | 3篇 |
农学 | 1篇 |
12篇 | |
综合类 | 7篇 |
农作物 | 9篇 |
水产渔业 | 2篇 |
畜牧兽医 | 32篇 |
园艺 | 4篇 |
植物保护 | 2篇 |
出版年
2022年 | 2篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 5篇 |
2013年 | 5篇 |
2012年 | 8篇 |
2011年 | 5篇 |
2010年 | 1篇 |
2009年 | 3篇 |
2008年 | 7篇 |
2007年 | 8篇 |
2006年 | 4篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 2篇 |
1998年 | 2篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1983年 | 4篇 |
1980年 | 1篇 |
排序方式: 共有72条查询结果,搜索用时 159 毫秒
1.
Anna Ohlson Jonas Malmsten Jenny Fr?ssling G?ran B?lske Anna Aspán Anne-Marie Dalin Ann Lindberg 《Acta veterinaria Scandinavica》2014,56(1):39
Background
Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii. Prevalence data in ruminant species are important to support risk assessments regarding public and animal health. The aim was to investigate the presence of or exposure to C. burnetii in cattle, sheep, goats and moose, and to compare two enzyme-linked immunosorbent assays (ELISAs). National surveys of antibodies against C. burnetii were performed for dairy cattle (n=1537), dairy goats (n=58) and sheep (n=518). Bovine samples consisted of bulk milk, caprine of pooled milk, and ovine of pooled serum. Antibodies were investigated in moose samples (n=99) from three regions. A one-year regional cattle bulk milk survey was performed on the Isle of Gotland (n=119, four occasions). Cattle, sheep and goat samples were analysed with indirect ELISA and moose samples with complement fixation test. For the sheep, goat, and parts of the cattle survey, samples were run in parallel by ELISAs based on antigens from infected ruminants and ticks. Bulk milk samples from the regional cattle survey and vaginal swabs from a subset of the sheep herds (n=80) were analysed for the agent by polymerase chain reaction. Spatial clustering was investigated in the national cattle survey.Results
The prevalence of antibodies in dairy herds was 8.2% with large regional differences. High risk clusters were identified in the southern regions. The prevalence among dairy herds on the Isle of Gotland varied from 55.9% to 64.6% and 46.4% to 58.9.0% for antibodies and agent, respectively, overall agreement between agent and antibodies was 85.2%. The prevalence of antibodies in sheep was 0.6%, the agent was not detected the vaginal swabs. Antibodies were not detected in goats or moose, although parts of the moose samples were collected in an area with high prevalence in cattle. The overall agreement between the two ELISAs was 90.4%.Conclusions
The prevalence of antibodies against C. burnetii in dairy cattle in Sweden shows large regional differences. The results suggest that C. burnetii is a rare pathogen among Swedish moose, dairy goat and sheep. ELISAs based on ruminant and tick antigen performed in a similar manner under Swedish conditions. 相似文献2.
Jonas Malmsten Lennart S?derquist Carl-Gustaf Thulin Dolores Gavier Widén Lisa Yon Michael R Hutchings Anne-Marie Dalin 《Acta veterinaria Scandinavica》2014,56(1):23
Background
The moose (Alces alces) is an intensively managed keystone species in Fennoscandia. Several aspects of reproduction in moose have not been fully elucidated, including puberty, timing of mating and oestrus, and the length of the oestrus period. These aspects are relevant for an adaptive management of moose with respect to harvest, population size, demography and environmental conditions. Therefore, an investigation of female moose reproduction was conducted during the moose-hunting period in southern Sweden from 2008 to 2011.Results
A total of 250 reproductive organs and information on carcass weight and age was collected from four different hunting areas (provinces of Öland, Småland, Södermanland, and Västergötland) in southern Sweden. The results showed that puberty in female moose varied with carcass weight, age, and time of season. The period for oestrous/mating lasted from about mid September to the beginning of November.Conclusions
The oestrus period (predominantly for heifers) is longer than previously reported and was not finished when the hunting period started. Sampling the uterine cervix to detect spermatozoa was a useful method to determine if mating had occurred. To avoid hunting of moose during oestrus, we suggest that the hunting period should be postponed by at least 14 days in southern Sweden. 相似文献3.
The concept of continuity/discontinuity is applied to the riparian vegetation of the corridor of the River Adour (S.W. France), in order to precisely define longitudinal structure, and to test the degree of floristic continuity of the fluvial axis. The measure of floristic connectance along the river course is based on presence/absence data, and is applied to successive stretches of the river, at various resolution levels. This analysis shows that the River Adour corridor cannot be assumed to be floristically continuous. The observed discontinuities may correspond to two types of change in the riparian vegetation: zones of slow change (high level of floristic connectance) or zones of sharp change (low level of floristic connectance). 相似文献
4.
5.
Michel E Baglin A Auvergne M Catala C Samadi R Baudin F Appourchaux T Barban C Weiss WW Berthomieu G Boumier P Dupret MA Garcia RA Fridlund M Garrido R Goupil MJ Kjeldsen H Lebreton Y Mosser B Grotsch-Noels A Janot-Pacheco E Provost J Roxburgh IW Thoul A Toutain T Tiphène D Turck-Chieze S Vauclair SD Vauclair GP Aerts C Alecian G Ballot J Charpinet S Hubert AM Lignières F Mathias P Monteiro MJ Neiner C Poretti E de Medeiros JR Ribas I Rieutord ML Cortés TR Zwintz K 《Science (New York, N.Y.)》2008,322(5901):558-560
Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the international community over the past decades. The CoRoT (Convection Rotation and Planetary Transits) satellite, launched in December 2006, has now measured oscillations and the stellar granulation signature in three main sequence stars that are noticeably hotter than the sun. The oscillation amplitudes are about 1.5 times as large as those in the Sun; the stellar granulation is up to three times as high. The stellar amplitudes are about 25% below the theoretic values, providing a measurement of the nonadiabaticity of the process ruling the oscillations in the outer layers of the stars. 相似文献
6.
Wengelnik K Vidal V Ancelin ML Cathiard AM Morgat JL Kocken CH Calas M Herrera S Thomas AW Vial HJ 《Science (New York, N.Y.)》2002,295(5558):1311-1314
During asexual development within erythrocytes, malaria parasites synthesize considerable amounts of membrane. This activity provides an attractive target for chemotherapy because it is absent from mature erythrocytes. We found that compounds that inhibit phosphatidylcholine biosynthesis de novo from choline were potent antimalarial drugs. The lead compound, G25, potently inhibited in vitro growth of the human malaria parasites Plasmodium falciparum and P. vivax and was 1000-fold less toxic to mammalian cell lines. A radioactive derivative specifically accumulated in infected erythrocytes to levels several hundredfold higher than in the surrounding medium, and very low dose G25 therapy completely cured monkeys infected with P. falciparum and P. cynomolgi. 相似文献
7.
Aguado E Richelme S Nuñez-Cruz S Miazek A Mura AM Richelme M Guo XJ Sainty D He HT Malissen B Malissen M 《Science (New York, N.Y.)》2002,296(5575):2036-2040
The transmembrane protein LAT (linker for activation of T cells) couples the T cell receptor (TCR) to downstream signaling effectors. Mice homozygous for a mutation of a single LAT tyrosine residue showed impeded T cell development. However, later they accumulated polyclonal helper T (TH) cells that chronically produced type 2 cytokines in large amounts. This exaggerated TH2 differentiation caused tissue eosinophilia and massive maturation of plasma cells secreting to immunoglobulins of the E and G1 isotypes. This paradoxical phenotype establishes an unanticipated inhibitory function for LAT that is critical for the differentiation and homeostasis of TH cells. 相似文献
8.
Anna Geraci Anne-Marie Chèvre Isabelle Divaret Frédérique Eber Francesco M. Raimondo 《Genetic Resources and Crop Evolution》2004,51(2):137-146
In Sicily and in the small surrounding islands the section Brassica of the genus Brassica comprises five species, B. insularis Moris, B. incana Ten., B. macrocarpa Guss., B. rupestris Raf. and B. villosa Biv. These taxa represent a genetic resource as relatives of kale crops but some populations are endangered or threatened, thus isozyme analyses were performed to assess the genetic diversity degree at population and species levels in order to assist the design of conservation management programs.Eleven loci from five enzyme systems (aconitase, leucine aminopeptidase, 6-phosphogluconate dehydrogenase, phosphoglucoisomerase phosphoglucomutase) were analyzed in sixteen natural population (fifteen from Sicily, one from Calabria). Mean within-population genetic diversity was moderate (P = 41%, A = 1.54, H = 0.16). In some cases a great number of heterozygous individuals were detected, in other cases fixation index (F) deviated significantly from Hardy-Weinberg genotypic expectations.A total of 37 alleles was recognized, six of which resulted exclusive to single populations. The among-population component of the total genetic diversity (Gst mean values) for each species was 0.30–0.37, indicating genetic differentiation among populations.Among B. villosa and B. rupestris populations genetic distance values resulted rather low and they resulted high with B. incana and B. macrocarpa populations.The results are discussed with regard to the distribution of the genetic diversity level and the genetic resources management. 相似文献
9.
Effects of garlic powders with varying alliin contents on hepatic drug metabolizing enzymes in rats 总被引:3,自引:0,他引:3
Le Bon AM Vernevaut MF Guenot L Kahane R Auger J Arnault I Haffner T Siess MH 《Journal of agricultural and food chemistry》2003,51(26):7617-7623
The anticarcinogenic effect of garlic has been demonstrated in both epidemiologic and experimental studies. In this study, possible mechanisms involved in the anticarcinogenic effect of garlic consumption were assessed by determining its capacity to alter drug metabolizing enzymes, in relation with its alliin content. Rats were fed a diet for 2 weeks containing 5% garlic powders produced from bulbs grown on soils with different levels of sulfate fertilization and therefore containing differing amounts of alliin. Activities of several hepatic enzymes, which are important in carcinogen metabolism such cytochromes P450 (CYP) and phase II enzymes, were determined. Garlic consumption slightly increased ethoxyresorufin O-deethylase and CYP 1A2 levels. In contrast, garlic consumption decreased CYP 2E1 activity and the level of the corresponding isoform. UDP glucuronosyl transferase and glutathion S-transferase activities were increased by garlic powders. The alliin content of the garlic powders was positively correlated with UGT activity although not with other activities. Effects produced by garlic consumption were qualitatively similar to that of diallyl disulfide, a sulfur compound that has been extensively studied. These data could partially explain the chemoprotective effect of garlic. 相似文献
10.
Walter J. Bruyninckx Anne-Marie B. Blancquaert 《Veterinary immunology and immunopathology》1983,4(4):493-504
Horse mononuclear cells were separated from whole blood using neutral density gradient centrifugation on Isopaque-Ficoll. The resulting cell suspension was comparable in composition with similarly prepared human and bovine mononuclear cell preparations. The relative concentration of monocytes was increased by the use of a gradient with density lower than that originally proposed by Böyum (Böyum, A. 1968. Scand. J. Clin. Lab. Investig. 21 supple. 97:77–89). Contamination by neutrophils was limited either by using a gradient medium of lower density or by replacing Isopaque-Ficoll by Percoll-0.9% NaCl. Although the density of the Isopaque-Ficoll appears to be the main determinant in the isolation method of Böyum, the mechanism of separation of the cell population is complex and a substantial variability of the results can be expected. 相似文献