全文获取类型
收费全文 | 432篇 |
免费 | 35篇 |
国内免费 | 1篇 |
专业分类
林业 | 42篇 |
农学 | 9篇 |
基础科学 | 4篇 |
89篇 | |
综合类 | 32篇 |
农作物 | 23篇 |
水产渔业 | 25篇 |
畜牧兽医 | 191篇 |
园艺 | 10篇 |
植物保护 | 43篇 |
出版年
2023年 | 6篇 |
2022年 | 9篇 |
2021年 | 19篇 |
2020年 | 20篇 |
2019年 | 17篇 |
2018年 | 21篇 |
2017年 | 21篇 |
2016年 | 16篇 |
2015年 | 21篇 |
2014年 | 28篇 |
2013年 | 26篇 |
2012年 | 36篇 |
2011年 | 50篇 |
2010年 | 25篇 |
2009年 | 17篇 |
2008年 | 29篇 |
2007年 | 22篇 |
2006年 | 12篇 |
2005年 | 21篇 |
2004年 | 16篇 |
2003年 | 10篇 |
2002年 | 10篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1988年 | 1篇 |
1984年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有468条查询结果,搜索用时 15 毫秒
111.
Tritrichomonas foetus and Mycoplasma felis coinfection in the upper respiratory tract of a cat with chronic purulent nasal discharge 下载免费PDF全文
Luca Pazzini Linda Mugnaini Francesca Mancianti Lorenzo Ressel 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2018,47(2):294-296
A 5‐year‐old indoor male neutered Siamese cat was presented with clinical signs of sneezing and chronic bilateral purulent nasal discharge. Multiple nasal cavity swabs were submitted for bacterial cultures, Mycoplasma felis‐DNA qPCR, and cytology. M felisqPCR was positive and cytomorphologic diagnosis was severe, acute, purulent, rhinitis with intralesional protozoal microorganisms consistent with a Trichomonas spp. Nested PCR (nPCR) confirmed the diagnosis of Tritrichomonas foetus. Systemic therapy with doxycycline for M felis and metronidazole for T foetus was started with remission of clinical signs within 2 weeks; however, symptoms relapsed shortly after therapy was discontinued. This study represents the first documented case of T foetus associated with chronic nasal discharge in a cat, which supports the hypothesis that T foetus can live in the nasal cavity. It is also the first reported case of M felis and T foetus coinfection, which indicates that with mycoplasmal feline upper respiratory tract infections, T foetus should be considered as a coinfecting agent. 相似文献
112.
Luca Ferrari Paolo Martelli Roberta Saleri Elena De Angelis Valeria Cavalli Marcello Bresaola Michele Benetti Paolo Borghetti 《Veterinary immunology and immunopathology》2013,151(3-4):193-206
The present study evaluated the lymphocyte activation in PRRSV-vaccinated pigs subsequently exposed to natural infection by in vitro stimulation of peripheral blood mononuclear cells (PBMC) with homologous vaccine and two heterologous PRRSV isolates. The responsiveness was assessed by determining IFN-γ secreting cells by ELISpot assay, lymphocyte CD8 phenotype by intracellular staining/flow cytometry, cytokine gene expression by real-time quantitative PCR and cytokine secretion by ELISA. Conventional pigs were weaned at 28 days of age and inoculated intramuscularly (IM) or needle-less intradermally (ID) with a modified-live PRRSV vaccine suspended in adjuvant, while control pigs were injected with adjuvant alone (ADJ). Blood samples were collected at vaccination, 35 days post-vaccination and after 35 days post-exposure to natural infection by a heterologous field strain. Thirty-five days post-vaccination, PRRSV vaccine induced a low but significant virus-specific IFN-γ secreting cell response upon stimulation with both the vaccine strain and the two isolates in vaccinated pigs. Conversely, after 35 days post-exposure, only the vaccine strain and the BS/114/S isolate triggered this response. Intracellular staining showed that PRRSV-specific immune cells reacting upon vaccine strain and BS/114/S stimulation were mostly CD8+ IFN-γ producing cells whereas the stimulation with BS/55 isolate induced an IFN-γ production associated to the CD8?IFN-γ+ phenotype. At 35 days post-vaccination, PBMC from vaccinated pigs showed lower IL-10 expression and release, and higher TNF-α gene expression upon stimulation with both the vaccine and viral isolates. After infection, both cytokines were not differently modulated in different groups. Immune parameters give evidence that IFN-γ secreting cells in the peripheral blood can be elicited upon PRRSV infection although vaccination itself does not stimulate high levels of these reactive cells. Moreover, the cross-reactivity against divergent PRRS viruses can show a different intensity and be differently associated with cytotoxic CD8+IFN-γ+ as well as CD8?IFN-γ+ cells. Overall, the obtained data confirmed that the immune activation against PRRSV is not dependent on the genetic divergence of the virus. Especially after infection, a different immune reactivity was evident upon stimulation with the different isolates in terms of frequency and CD8 phenotype of PRRSV-specific IFN-γ producing cells. The modulation of cytokines in vaccinated pigs appeared to be more dependent on vaccination or infection conditions than on stimulation by different isolates, and the changes of IL-10 more relevant than those of TNF-α at gene and protein levels. Moreover, under the conditions of this study, the PRRSV vaccine administered via the intradermal route by a needle-less device was confirmed to induce an immune response comparable or in some cases higher than the intramuscular route. 相似文献
113.
When compared to that of normal animals, calcium-binding protein activity of duodenal mucosa obtained from uremic rats was decreased. There was no change in this activity after vitamin D(3), therapy. In contrast, prior treatment with 25-hydroxycholecalcijerol resulted in increased transport of calcium-45 and calcium-binding protein activity in the intestine. 相似文献
114.
Meningiomas are the most common primary brain tumours in dogs and cats. There are several morphological phenotypes of this extra-axial neoplasm and they show predilections for certain anatomical locations. There have been a number of attempts to apply the current World Health Organization (WHO) classification for human meningiomas to dogs and cats and to obtain a universal classification scheme for domestic animals. Recently, certain enzymes involved in tumour growth have been recognised as biological markers and have been related to degrees of malignancy. The secondary effects of meningiomas have also been investigated, and vascular endothelial growth factor and peritumoural oedema have been reported to reduce survival rate. Breed and age predisposition are recognised in both dogs and cats and the presenting clinical signs are quite consistent. Magnetic resonance imaging and computed tomography are the techniques of choice for the presumptive diagnosis of meningiomas in domestic animals but advanced imaging techniques are constantly being developed and applied. Treatment methods for meningiomas involve a combination of de-bulking surgery, chemotherapy and radiotherapy, and detailed accounts of several treatment protocols have been reported. 相似文献
115.
116.
Jones T Ehardt CL Butynski TM Davenport TR Mpunga NE Machaga SJ De Luca DW 《Science (New York, N.Y.)》2005,308(5725):1161-1164
A distinct species of mangabey was independently found at two sites 370 kilometers apart in southern Tanzania (Mount Rungwe and Livingstone in the Southern Highlands and Ndundulu in the Udzungwa Mountains). This new species is described here and given the name "highland mangabey" Lophocebus kipunji sp. nov. We place this monkey in Lophocebus, because it possesses noncontrasting black eyelids and is arboreal. L. kipunji is distinguished from other mangabeys by the color of its pelage; long, upright crest; off-white tail and ventrum; and loud call. This find has implications for primate evolution, African biogeography, and forest conservation. 相似文献
117.
Tundis R Loizzo MR Menichini F Bonesi M Conforti F Statti G De Luca D de Cindio B Menichini F 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(3):261-269
The present study aimed to evaluate for the first time the phenols, flavonoids, carotenoids, capsaicin and dihydrocapsaicin
content and the antioxidant and hypoglycemic properties of Capsicum annuum var. acuminatum small and C. annuum var. cerasiferum air-dried fruits. The ethanol extract of C. annuum var. acuminatum small, characterized by the major content of total poliphenols, flavonoids, carotenoids and capsaicinoids, showed the highest
radical scavenging activity (IC50 of 152.9 μg/ml). On the contrary, C. annuum var. cerasiferum showed a significant antioxidant activity evaluated by the β-carotene bleaching test (IC50 of 3.1 μg/ml). The lipophilic fraction of both C. annuum var. acuminatum and C. annuum var. cerasiferum exhibited an interesting and selective inhibitory activity against α-amylase (IC50 of 6.9 and 20.1 μg/ml, respectively). 相似文献
118.
Ilaria Pertot Davide Gobbin Federica De Luca Daniele Prodorutti 《Crop Protection》2008,27(7):1061-1070
Armillaria mellea (Vahl:Fr.) P. Kumm. is the causal agent of root rots of numerous perennial woody plants, including grapevine. In grapevine, A. mellea infections cause reduced plant vigour, poor grape quality and, in the last stage of the disease, plant death. No post-infection control agents are available for use against this disease. Disease management programmes rely solely on prophylactic measures. Therefore, knowledge of the distribution pattern of the disease over time, disease incidence and actual losses due to the disease across geographical areas is crucial. We evaluated the use of aerial photographs, surveys of growers’ experiences and field assessments to estimate the incidence of Armillaria root rot in a viticultural area (140 ha) situated in the Piana Rotaliana region (Italy). Results of the 4-year assessment were that 25% of the vineyards (36 ha) were infected by Armillaria, 2% of the cultivated vines exhibited disease symptoms and 0.25% of the vines died each autumn. The causal agent was almost exclusively A. mellea but, in two cases, Armillaria gallica was also isolated. The genetic diversity of the Italian population, according to IGS sequencing and somatic incompatibility testing, was very high, suggesting multiple pathogen introduction sites and the slow, vegetative underground spread of the fungus. Fungal clones were found within individual vineyards. Even if, within a particular area, the disease is spreading very slowly and crop losses are limited (one vine out of 400 dies each year), an effective agronomic plan for the prevention of infections should be implemented. 相似文献
119.
120.
Wheat is a good source of polyphenols, plant metabolytes with beneficial effects on human health. However, little information is available on phenolic acid composition and concentration in different Triticum species, as well as on possible environmental effects. To shed some light on this issue, thirty-nine wheat accessions cropped for two years and belonging to different Triticum species (Triticum monococcum, Triticum turgidum ssp. dicoccum, turanicum and durum, Triticum aestivum ssp. spelta and aestivum) were assessed for phenolic acids (ferulic, p-coumaric, vanillic, syringic, p-hydroxybenzoic, caffeic acids and syringaldehyde), total polyphenols and antioxidant activity in soluble conjugated and insoluble bound extracts. Ferulic acid was the most abundant compound in both extracts. Insoluble bound phenolic acids represented >90% of total phenolic acids. Einkorn showed the maximum concentration of conjugated phenolic acids (50.5 mg/kg DM), while durum and bread wheats presented the highest content of bound phenolic acids (651.8 and 629.2 mg/kg DM, respectively). Cropping year influenced the concentration of conjugated but not of bound phenolic acids. A survey of phenolic acid distribution in the kernel showed that they are rare in endosperm, but abundant in germ and bran. Total polyphenols and antioxidant activity were highly correlated to phenolic acid content. 相似文献