全文获取类型
收费全文 | 528篇 |
免费 | 49篇 |
专业分类
林业 | 32篇 |
农学 | 1篇 |
基础科学 | 2篇 |
126篇 | |
综合类 | 30篇 |
农作物 | 21篇 |
水产渔业 | 35篇 |
畜牧兽医 | 269篇 |
园艺 | 14篇 |
植物保护 | 47篇 |
出版年
2023年 | 13篇 |
2022年 | 9篇 |
2021年 | 18篇 |
2020年 | 23篇 |
2019年 | 19篇 |
2018年 | 29篇 |
2017年 | 28篇 |
2016年 | 23篇 |
2015年 | 12篇 |
2014年 | 26篇 |
2013年 | 44篇 |
2012年 | 39篇 |
2011年 | 45篇 |
2010年 | 27篇 |
2009年 | 19篇 |
2008年 | 35篇 |
2007年 | 39篇 |
2006年 | 23篇 |
2005年 | 29篇 |
2004年 | 26篇 |
2003年 | 12篇 |
2002年 | 16篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1989年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1977年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有577条查询结果,搜索用时 0 毫秒
571.
Fabio Franco Stellari Sophia Lavrentiadou Francesca Ruscitti Sarah Jacca Valentina Franceschi Maurizio Civelli Chiara Carnini Gino Villetti Gaetano Donofrio 《Veterinary research》2014,45(1):8
Polymorphonuclear cells diapedesis has an important contribution to the induced Mannhemia haemolytica (M. haemolytica) infection lung inflammation and IL-8 is the primary polymorphonuclear chemoattractant. Using a bovine IL-8/luciferase transiently transgenized mouse model, the orchestration among M. haemolytica, IL-8 promoter activation and neutrophilia was followed in real time by in vivo image analysis. 相似文献
572.
Francesca Latronico Arshnee Moodley S?ren Saxmose Nielsen Luca Guardabassi 《Veterinary research》2014,45(1):70
The recent worldwide spread of methicillin-resistant Staphylococcus pseudintermedius (MRSP) in dogs is a reason for concern due to the typical multidrug resistance patterns displayed by some MRSP lineages such as sequence type (ST) 71. The objective of this study was to compare the in vitro adherence properties between MRSP and methicillin-susceptible (MSSP) strains. Four MRSP, including a human and a canine strain belonging to ST71 and two canine non-ST71 strains, and three genetically unrelated MSSP were tested on corneocytes collected from five dogs and six humans. All strains were fully characterized with respect to genetic background and cell wall-anchored protein (CWAP) gene content. Seventy-seven strain-corneocyte combinations were tested using both exponential- and stationary-phase cultures. Negative binomial regression analysis of counts of bacterial cells adhering to corneocytes revealed that adherence was significantly influenced by host and strain genotype regardless of bacterial growth phase. The two MRSP ST71 strains showed greater adherence than MRSP non-ST71 (p < 0.0001) and MSSP (p < 0.0001). This phenotypic trait was not associated to any specific CWAP gene. In general, S. pseudintermedius adherence to canine corneocytes was significantly higher compared to human corneocytes (p < 0.0001), but the MRSP ST71 strain of human origin adhered equally well to canine and human corneocytes, suggesting that MRSP ST71 may be able to adapt to human skin. The genetic basis of the enhanced in vitro adherence of ST71 needs to be elucidated as this phenotypic trait may be associated to the epidemiological success and zoonotic potential of this epidemic MRSP clone. 相似文献
573.
Veronica Piazza Ivanka Dragi? Kristina Sep?i? Marco Faimali Francesca Garaventa Tom Turk Sabina Berne 《Marine drugs》2014,12(4):1959-1976
Polymeric alkylpyridinium salts (poly-APS) isolated from the Mediterranean marine sponge, Haliclona (Rhizoniera) sarai, effectively inhibit barnacle larva settlement and natural marine biofilm formation through a non-toxic and reversible mechanism. Potential use of poly-APS-like compounds as antifouling agents led to the chemical synthesis of monomeric and oligomeric 3-alkylpyridinium analogues. However, these are less efficient in settlement assays and have greater toxicity than the natural polymers. Recently, a new chemical synthesis method enabled the production of poly-APS analogues with antibacterial, antifungal and anti-acetylcholinesterase activities. The present study examines the antifouling properties and toxicity of six of these synthetic poly-APS using the barnacle (Amphibalanus amphitrite) as a model (cyprids and II stage nauplii larvae) in settlement, acute and sub-acute toxicity assays. Two compounds, APS8 and APS12-3, show antifouling effects very similar to natural poly-APS, with an anti-settlement effective concentration that inhibits 50% of the cyprid population settlement (EC50) after 24 h of 0.32 mg/L and 0.89 mg/L, respectively. The toxicity of APS8 is negligible, while APS12-3 is three-fold more toxic (24-h LC50: nauplii, 11.60 mg/L; cyprids, 61.13 mg/L) than natural poly-APS. This toxicity of APS12-3 towards nauplii is, however, 60-fold and 1200-fold lower than that of the common co-biocides, Zn- and Cu-pyrithione, respectively. Additionally, exposure to APS12-3 for 24 and 48 h inhibits the naupliar swimming ability with respective IC50 of 4.83 and 1.86 mg/L. 相似文献
574.
Damianidis Christos Santiago-Freijanes Jose Javier den Herder Michael Burgess Paul Mosquera-Losada Maria Rosa Graves Anil Papadopoulos Andreas Pisanelli Andrea Camilli Francesca Rois-Díaz Mercedes Kay Sonja Palma Joao H. N. Pantera Anastasia 《Agroforestry Systems》2021,95(5):919-929
Agroforestry Systems - Wildfires have always been an integral part of the ecology of many terrestrial ecosystems, but their frequency is increasing in many parts of the world. Wildfires were once a... 相似文献
575.
Veronica Marchetti George Lubas Gad Baneth Mario Modenato Francesca Mancianti 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(1):121-125
Abstract: A 15‐month‐old, female mongrel dog was presented with a 6‐week history of inappetence, weight loss, and tetraparesis. Physical examination revealed weakness, poor body condition, mild fever, pale mucous membranes, and diffuse muscle atrophy. The right hind limb was painful and edematous, with large ecchymoses. The femur was irregular on palpation and moderate popliteal lymphadenopathy was evident. Results of a CBC showed severe anemia with mild regeneration, an inflammatory leukogram with 90% of neutrophils parasitized by Hepatozoon sp. gamonts, and moderate thrombocytopenia. A bone marrow aspirate had myeloid hyperplasia and contained a few extracellular Hepatozoon meronts and a few intracellular gamonts within neutrophils. Serum chemistry abnormalities included hypoalbuminemia, hyperglobulinemia, hypoglycemia, hypercalcemia, hyperphosphatemia, and elevated alkaline phosphatase activity. Radiologic findings of the right femur included periosteal bone proliferation and lesions compatible with osteomyelitis. A fine needle aspirate specimen from the bone lesion had neutrophilic inflammation; 36% of the neutrophils contained Hepatozoon gamonts. Results of cerebrospinal fluid analysis included a protein concentration of 37 mg/dL and marked mononuclear pleocytosis (243 cell/μL) with a predominance of lymphocytes. An ELISA was positive for Hepatozoon canis and PCR results with DNA sequencing confirmed infection with this organism. A diagnosis of hepatozoonosis with skeletal involvement and meningoencephalomyelitis was made. The dog recovered almost completely neurologically and had no gamonts in the blood after 60 days of therapy with imidocarb dipropionate and prednisone. This is an unusual case of canine hepatozoonosis involving neurologic signs and a periosteal reaction more typical of H. americanum infection and rarely reported in dogs infected with H. canis. 相似文献
576.
Samantha L. Eaton Mary-Jo Anderson Scott Hamilton Lorenzo Gonzlez Jill Sales Martin Jeffrey Hugh W. Reid Mara S. Rocchi Francesca Chianini 《Veterinary immunology and immunopathology》2009,131(1-2):105-109
In order to gain a better understanding of the pathogenesis of scrapie in sheep an experimental model was developed to characterise immune system cells in the minutes following inoculation with scrapie-brain homogenate. Four 1-year-old susceptible (ARQ/ARQ) sheep were inoculated via the subcutaneous route at four different peripheral lymph node (LNs) drainage sites, at specific time points, prior to euthanasia of the sheep. The LNs were removed post-mortem at 30, 90, 180 and 300 min after inoculation. Flow cytometric triple-labelling was carried out on the LN cells and indicated that inoculation of scrapie-brain homogenate adjacent to a lymph node may delay or even inhibit the number of host CD21+ B cells expressed within the first 5 h. Immunohistochemistry was used to attempt detection of the abnormal form of prion protein (PrPsc) in draining LNs adjacent to inoculation sites, with negative results at those time points. 相似文献
577.
Margherita Santoni Leonardo Verdi Shamina Imran Pathan Marco Napoli Anna Dalla Marta Francesca Romana Dani Gaio Cesare Pacini Maria Teresa Ceccherini 《Soil Use and Management》2023,39(1):588-605
The implementation of environmentally friendly agricultural policies has increased the need to compare agricultural aspects of conventional (CON) and organic farming (ORG) systems. The objective of the present work was to compare the effects of an organic and conventional long-term experiment on bacterial and fungal biomass and activity, as well as soil CO2 emission and readily available nitrogen forms in a soil cultivated with Helianthus annuus L. The microbial biomass was more active and abundant in ORG as well as soil CO2 emission. Despite being less abundant, fungi were more active than bacteria in both ORG and CON experiments. 16S rRNA gene sequencing showed that the ORG treatment had a significantly greater bacterial richness than CON. Cyanobacteria, Actinobacteria and Proteobacteria were the most abundant phyla contributing more than others to the differences between the two systems. Moreover, the soil and content was not significantly different between ORG and CON, while was less in ORG. ORG sunflower yield was significantly less compared with CON. While much remains to be discovered about the effects of these agricultural practices on soil chemical properties and microbial diversity, our findings may contribute to this type of investigation. 相似文献