全文获取类型
收费全文 | 170篇 |
免费 | 15篇 |
专业分类
林业 | 9篇 |
37篇 | |
综合类 | 9篇 |
农作物 | 7篇 |
水产渔业 | 9篇 |
畜牧兽医 | 101篇 |
园艺 | 1篇 |
植物保护 | 12篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 6篇 |
2019年 | 10篇 |
2018年 | 3篇 |
2017年 | 6篇 |
2016年 | 6篇 |
2015年 | 4篇 |
2014年 | 1篇 |
2013年 | 12篇 |
2012年 | 5篇 |
2011年 | 15篇 |
2010年 | 14篇 |
2009年 | 2篇 |
2008年 | 10篇 |
2007年 | 6篇 |
2006年 | 8篇 |
2005年 | 3篇 |
2004年 | 6篇 |
2003年 | 6篇 |
2002年 | 8篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 7篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有185条查询结果,搜索用时 17 毫秒
111.
Paul D. Carranco Armando Hernández Fermín Rivera Irma Rosas 《Water, air, and soil pollution》1984,23(3):249-256
Twenty fungal strains were isolated from a small waste-stabilization pond system near Santo Tomás Atzingo, Mexico, using a number of plating and enrichment culture techniques. Among isolates, only Pythium sp. was aquatic. Eight fungi of interest to the plant-pathologist were recovered. Seven strains hydrolyzed casein and four amylum. All isolates, with the exception of Phoma sp., formed colonies in culture media with surfactant levels of 10 mg L?1. Eleven strains proved to be acid-formers. 相似文献
112.
Butler Eric P. Bliss-Ketchum Leslie L. de Rivera Catherine E. Dissanayake Sahan T. M. Hardy Carole L. Horn Dorothy A. Huffine Ben Temple Amanda M. Vermeulen Michael E. Wallace Hailey 《Landscape Ecology》2022,37(1):1-29
Landscape Ecology - Connections among ecosystems and their components are critical to maintaining ecological functions and benefits in human-modified landscapes, including urban areas. However, the... 相似文献
113.
Seasonal distribution of air-borne pathogenic and free-living amoebae in Mexico City and its suburbs
Dr. Fermin Rivera Patricia Bonilla Elizabeth Ramirez Arturo Calderon Elvia Gallegos Salvador Rodriguez Ricardo Ortiz Dolores Hernandez Victor Rivera 《Water, air, and soil pollution》1994,74(1-2):65-87
A survey was carried out over a one-year period to isolate amoebae suspended in the air of Mexico City and its suburbs. Sampling stations were placed at the four cardinal points of the metropolitan area. Selective media were used to culture the amoebae isolated. Specialized taxonomic keys and physical and physiological tests were used for identification, and a statistical analysis was performed to determine the correlations between physico-chemical and biological parameters. 108 strains were isolated, of which 19 were pathogenic via intracerebral inoculation and 9 via intranasal inoculation. Species of the generaAcanthamoeba, Vahlkampfia andHartmannella were most abundant.Acanthamoeba polyphaga showed the highest abundance. Several times during the period of the study SO2 O3, CO, NO and NO2 exceeded the permissible levels established by the Mexican government. The ability of amoebae to form cysts and cyst size were important factors for their presence, survival, abundance and diversity in the atmosphere. The main source of air-borne amoebae was the soil. Factors that favored the incidence and diversity of the isolates were wind speed and direction, low relative humidity, generation of frequent dust-storms, resuspension of amoebae by vehicular traffic, proximity to garbage dumps and large extensions of bare soil. Soil cover was a factor associated with a reduction in the incidence and diversity of the aerial amoebae. This study demonstrates that there are viable cysts of amoebae in the atmosphere of Mexico City, that may have potential importance in the case of certain kinds of human allergies and diseases. Further research is needed to find out the aerial presence of viable cysts of obligatory, amphizoic or opportunistic amoebic parasites, and to clarify the qualitative and quantitative effects of the local meteorological and physico-chemical environment on the free-living amoebae present in the atmosphere. 相似文献
114.
Cristina?InocencioEmail author Robyn?S.?Cowan Francisco?Alcaraz Diego?Rivera Mike?F.?Fay 《Genetic Resources and Crop Evolution》2005,52(2):137-144
A genetic fingerprinting technique (AFLP) was used to determine the relationships among Capparis spp. Genetic distances, based on AFLP data were estimated for 45 accessions of Capparis species, from Spain, Morocco and Syria. The results of this analysis support the differentiation of four of the five taxa involved. The group of plants recognised as C. spinosa on the basis of morphological characters, includes several cultivars and appears in an intermediate position between C. orientalis and C. sicula and overlaps with C. orientalis. The other two species C. aegyptia and C. ovata are separate from the rest. Capparis spinosa had a low number of unique bands in comparison with the other species. Although these results cannot confirm the hybrid origin of C. spinosa, the distribution of the bands supports this hypothesis, the most likely parental species being C. orientalis and C. sicula. 相似文献
115.
Daniel D Benetti Mehmet R Orhun Bruno Sardenberg Brian O'Hanlon Aaron Welch Ronald Hoenig Ian Zink José A Rivera Bristol Denlinger Donald Bacoat Kevin Palmer & Fernando Cavalin 《Aquaculture Research》2008,39(7):701-711
This paper describes advances in hatchery and grow‐out technology of cobia (Rachycentron canadum, Linnaeus). In 2007, methods for capture, transport, acclimation, sampling, conditioned spawning, larval rearing, fingerling production, nursery, shipping and grow‐out have been perfected. Survival rates ranging from 17.5% to 35% were achieved from egg to shipping size fingerlings (1.0 g) in 2007 at the University of Miami Experimental Fish Hatchery, with production of approximately 20 000 fingerlings per 12 000 L tank. Wild and F1 broodstock cobia have been conditioned to spawn through temperature manipulation producing viable eggs for experimental and production level larval rearing trials in several hatcheries. Brood fish have also been induced to spawn using hormones. Cobia appear to be susceptible to infestations by parasitic protozoa such as Amyloodinium ocellatum and to infections caused by deleterious bacteria such as Photobacterium spp. and Vibrio spp. Prophylactic methods used to prevent and control epizootic diseases at the hatchery are summarized. Improved techniques for cage management were implemented, and both novel designs of submerged cages deployed in exposed areas and traditional gravity cages in protected areas have been used for commercial ongrowing of cobia in the Americas and the Caribbean region. 相似文献
116.
C Rehbinder E Gimeno K Belák S Belák M Stéen E Rivera T Nikkil? 《The Veterinary record》1991,129(25-26):552-554
A disease of unknown aetiology has been observed in moose. The animals showed signs of a bovine viral diarrhoea/mucosal disease-like syndrome, and central nervous disturbances. Brains from adult female moose were investigated by means of histology, immunohistochemistry, electron microscopy, virology, and bacteriology. The results indicate that the nervous signs were not associated with a spongiform encephalopathy. The lesions suggest a viral aetiology, although all the virological investigations have so far proved negative. 相似文献
117.
Rivera S Divers SJ Knafo SE Martinez P Cayot LJ Tapia-Aguilera W Flanagan J 《The Veterinary record》2011,168(3):78
Lidocaine intrathecal anaesthesia was used to perform phallectomies in 15 hybrid Galapagos tortoises (Geochelone nigra) in a field setting as part of a conservation and ecosystem restoration project in the Galapagos Islands. The intrathecal injection was performed in the dorsal intercoccygeal region of the tail. Once the tail and hindlimbs were relaxed and the phallus was easily exteriorised, phallectomy was performed in a routine manner. All the animals recovered well from the procedure and were walking 30 to 60 minutes after surgery. No adverse effects were noted as a result of lidocaine intrathecal anaesthesia. One of the larger animals had evidence of haemorrhage from the surgical site 48 hours postoperatively. All tortoises continued to make full recoveries and were released on to the island of Pinta in May 2010. 相似文献
118.
Herrera E Rivera A Palomares EG Hernández-Castro R Díaz-Aparicio E 《Tropical animal health and production》2011,43(6):1069-1070
The purpose of this study is to determine the etiology of abortions presented in a goat herd declared as free of brucellosis
and vaccinated with RB51 located in Mexico. The serological diagnosis of brucellosis in 33 animals was performed. The study
included three goats that aborted in the last third of gestation and 15 goats that gave birth normally; samples of milk and
vaginal exudate were subjected to bacteriological study. All animals were negative for serological diagnosis, and isolation
of Brucella melitensis was achieved in a single goat from vaginal exudate. However, the particularity is that this goat was negative to the card,
indirect ELISA, and radial immunodiffusion tests. Isolation of a field strain was confirmed by biochemical test resistance
to rifampicin and PCR. It is concluded that a goat which aborted in the last third of gestation was found spreading B. melitensis through vaginal discharge despite being vaccinated with RB51 and seronegative for brucellosis. 相似文献
119.
Fermín Rivera Alfonso Lugo Jesús Ponce Fernando Lares Ricardo Ortiz 《Water, air, and soil pollution》1986,27(1-2):199-214
A protozoological survey was performed on waste stabilization lagoons to isolate, identify, and determine the incidence of zooflagellates present in these waters. A correlation between the species found and the physicochemical parameters determined was also done. Fifteen samplings were analyzed from June 1981 to April 1982. Free-living zooflagellates included: Bodo edax Klebs: Bodo caudatus Dujardin;Trepomonas agilis Dujardin;Pleuromonas jaculans Perty (all of them polisaprobic indicators);Bodo saltans Ehrenberg (a mesosaprobic indicator); and Bodomorpha minima Hollande. A human commensal species Enteromonas hominis Da — Fonseca, was also isolated. The performance of the lagoons was predominantly anaerobic. The temperature seemed to be the most influential factor on the incidence of the zooflagellates isolated, especially in winter time. 相似文献
120.