首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   24篇
  免费   1篇
林业   2篇
畜牧兽医   11篇
植物保护   12篇
  2020年   1篇
  2019年   2篇
  2017年   1篇
  2016年   4篇
  2015年   2篇
  2014年   1篇
  2012年   1篇
  2011年   1篇
  2010年   1篇
  2008年   5篇
  2007年   2篇
  2006年   1篇
  2005年   2篇
  2003年   1篇
排序方式: 共有25条查询结果,搜索用时 93 毫秒
1.
2.
Microcyclic conidiogenesis (MC), a process defined as the production of conidia on a spore without any, or only a minimal, involvement of hyphal growth, has recently been reported in a little known powdery mildew species, Oidium longipes. To investigate whether this was an isolated case or it is a more general phenomenon in powdery mildew fungi, germinating conidia of eight species of the Erysiphales were examined using light microscopy. The following species were included in this work: Erysiphe necator on grapevine, Blumeria graminis f. sp. hordei on barley, Podosphaera xanthii on cucumber, Erysiphe sp. on Ligustrum vulgare, O. longipes on Petunia x grandiflora, O. neolycopersici on tomato, Golovinomyces cichoracearum on Rudbeckia laciniata and Sawadaea sp. on Acer negundo. In all these species, up to 4% of the germinated conidia exhibited MC. Moreover, when colonies of E. necator and O. neolycopersici, on detached grapevine and tomato leaves, respectively, were treated with a conidial suspension of Ampelomyces, the intracellular pycnidia of these mycoparasites appeared in microcyclic conidiophores. This represents a yet undescribed method of accelerating asexual reproduction in this mycoparasite. In the life cycle of powdery mildews, the importance of MC is still not clear but it should be taken into consideration when conidial germination is studied on the host surface for purposes such as epidemiology or species identification.  相似文献   
3.
4.
In this study, the utility of a commercial intravaginal thermometer was evaluated as an automated method for the prediction of calving in a total of 257 healthy pregnant Holstein–Friesian female cattle. The accuracy and the sensitivity of predicting calving within 48 hr before calving were also evaluated. The intravaginal temperature changes from 72 hr before and up to calving were significantly (p ≤ .001) affected by parity, season (summer vs. autumn), the time of day (8 a.m. or 8 p.m.) and the 6-hr time intervals (38.19°C: first interval 0 to 6 hr before calving vs. 38.78°C: twelfth interval 66 to 72 hr before calving), while the gender (p = .943), and the weight of the calf (p = .610), twinning (p = .300), gestation length (p = .186), foetal presentation (p = .123), dystocia (p = .197) and retention of foetal membranes (p = .253) did not affect it significantly. The sensitivity of the SMS of expecting calving within 48 hr and the positive predictive value were 62.4% and 75%, respectively, while the sensitivity and the positive predictive value for the SMS of expulsion reached 100%. It can be concluded that the investigated thermometer is not able to predict calving within 48 hr accurately; however, imminent calving can be accurately alerted.  相似文献   
5.
There are approximately 40 fungal species that have so far been reported as natural antagonists of powdery mildews or have been tested as their potential biocontrol agents. This review summarizes the published data on their identification, taxonomy, ecology, modes of action and biocontrol efficacy. The results obtained with the two products already registered, AQ10 Biofungicide and Sporodex, are also discussed.  相似文献   
6.
Cases of equine abortion and perinatal foal losses were investigated in Hungary during a three-year period (1998-2000). Samples from aborted equine fetuses and newborn foals (total n = 96) were examined using bacteriological, virological, pathological, immunohistochemical (IHC), molecular biological and serological methods. The cause of abortion and perinatal foal loss was identified in 67/96 cases (70%); viral infection was found in 22 (23%), viral and bacterial coinfection in 1 (1%), bacterial infection in 23 (24%), protozoan infection in 1 (1%) and fungal infection in 2 cases (2%). Morphological lesions suggestive of infection were recorded in 2 (2%) and non-infectious causes in 16 cases (17%).  相似文献   
7.
Klebsiella (K.) oxytoca infection induced the abortion of a female equine fetus in the 10th month of pregnancy. Bacteria were cultured from the liver, lung and stomach content. They were labelled with an anti-Mycobacterium bovis antibody in the thymus, liver and lungs and were stained with Giemsa and Brown-Brenn staining in the thymus and lung. The diffusely consolidated lungs contained numerous grey-whitish foci 2-4 mm in diameter, which corresponded to severe pyogranulomatous pneumonia characterised by numerous intraalveolar neutrophils and macrophages and multinucleated Langhans' giant cells. K. oxytoca was located in the cytoplasm of these cells, and extracellularly in the lumen of alveoli, bronchioles and bronchi, in the capsule of thymus and in the sinusoids of the liver. The results indicate that K. oxytoca can cause sporadic equine abortion.  相似文献   
8.
9.
10.
The nano‐sized (100–500 nm) selenium has higher bioavailability and relatively lower toxicity compared to other selenium forms. The objective of the present study was to compare liver proteome profiles of broiler chicken fed with control diet without Se supplementation and diet supplemented with nano‐Se with 4.25 mg/kg DM. Differential proteome analyses were performed by two‐dimensional gel electrophoresis (2D‐PAGE) followed by tryptic digestion and protein identification by liquid chromatography–mass spectrometry (LC‐MS). Seven hundred and eight spots were detected, and 18 protein spots showed significant difference in their intensity (p < 0.05) between the two groups. In response to nano‐Se supplementation, the expression of 8 proteins was higher, and 5 proteins were lower in nano‐Se supplemented group compared to control group. The functions of the differentially expressed proteins indicate that the high dose of selenium supplementation induced a dietary stress. Selenium supplementation may influence the metabolism of fatty acids and carbohydrates and antioxidant system, and increase the quantity of cytoskeletal actin and the expression of actin regulatory protein as well.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号