全文获取类型
收费全文 | 211篇 |
免费 | 8篇 |
专业分类
林业 | 12篇 |
基础科学 | 1篇 |
13篇 | |
综合类 | 32篇 |
农作物 | 1篇 |
水产渔业 | 9篇 |
畜牧兽医 | 147篇 |
园艺 | 2篇 |
植物保护 | 2篇 |
出版年
2022年 | 4篇 |
2021年 | 3篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 10篇 |
2011年 | 15篇 |
2010年 | 10篇 |
2009年 | 6篇 |
2008年 | 11篇 |
2007年 | 5篇 |
2006年 | 10篇 |
2005年 | 14篇 |
2004年 | 12篇 |
2003年 | 11篇 |
2002年 | 10篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1990年 | 3篇 |
1989年 | 5篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 5篇 |
1971年 | 4篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1963年 | 1篇 |
1947年 | 1篇 |
1943年 | 2篇 |
1942年 | 2篇 |
1941年 | 1篇 |
1940年 | 1篇 |
1906年 | 1篇 |
1901年 | 1篇 |
排序方式: 共有219条查询结果,搜索用时 3 毫秒
1.
2.
3.
Samples and observations under 420 meters of ice and 430 kilometers from the open sea on the Ross Ice Shelf at a water depth of 597 meters revealed an unusual assemblage of benthic organisms. Scavenging amphipods, an isopod, and fish were present but a living infauna was absent. The observations may be accounted for by sampling or spatial bias, or by extremely low or fluctuating trophic resources. 相似文献
4.
Mehinagic E Royer G Symoneaux R Jourjon F Prost C 《Journal of agricultural and food chemistry》2006,54(7):2678-2687
The aroma and texture of three different apple cultivars, harvested at three maturity stages, were analyzed by sensory and instrumental analysis. The emphasis was on the identification of the most potent odorant volatiles, and the challenge was to separate the few most important flavor compounds, which may be trace chemicals, from the vast number of nonodorant compounds present in apple aroma extracts. Thirty-six odorant compounds were detected, 24 of which were common to all extracts. A significant correlation coefficient was found between the aroma intensity scores and overall quantity of the odorant volatiles, which shows that the development of sensory aroma is similar to that of odorant volatiles. This study also showed that the parameters measured by penetrometry and compression were highly correlated with sensory textural attributes. The determination of the optimal maturity stage for different apple cultivars by the usual parameters, such as color, diameter, total soluble solids, and titrable acidity, may not be sufficient to determine the optimal sensory quality for consumers. Moreover, the sensory quality of fruits changes during maturation in a different way from one cultivar to another, and this should be taken into account. 相似文献
5.
Ethylene glycol toxicosis in a free-ranging raccoon (Procyon lotor) from Prince Edward Island 下载免费PDF全文
Foley P McBurney S 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(4):291-292
A juvenile free-ranging raccoon (Procyon lotor) was presented for acute onset of abnormal mentation and seizures. Ethylene glycol toxicosis was diagnosed on postmortem examination. This report highlights the importance of including ethylene glycol toxicosis on the list of differential diagnoses for abnormal mentation and seizures in free-ranging raccoons. 相似文献
6.
"Kennel cough" in dogs in animal shelters is readily transmissible, reduces adoption rates, and commonly leads to the euthanasia of affected dogs. In cats, tracheobronchitis, conjunctivitis, and pneumonia have been associated with Bordetella bronchiseptica infection-but most cases of upper-respiratory infection (URI) probably are caused by herpesvirus and calicivirus, and many B. bronchiseptica culture-positive cats are clinically normal. Our prospective observational study was undertaken to document the contribution of B. bronchiseptica to disease in cats and dogs from two animal shelters undergoing outbreaks of canine kennel cough, to evaluate whether cross-species transmission might have occurred, and to determine if the presence of infected cats represented a risk to dogs. Clinically defined cases of kennel cough in dogs and URI in cats were investigated in two shelters by calculating clinical-disease incidence, alveolar-lavage cytological examination, bacterial and viral cultures, antibiotic-susceptibility testing, and molecular fingerprinting by pulsed-field gel electrophoresis.In a 40-cat and 40-dog "no-kill" shelter, the prevalences of culture positivity were 47% for B. bronchiseptica and 36% for calicivirus at the same time as two resident dogs demonstrated clinical cough. When no dogs had kennel cough 3 months later, 10% of cats were B. bronchiseptica-culture-positive and 63% calicivirus positive. In a large traditional shelter, the incidence of kennel cough in dogs increased over 12 weeks to a maximum of 19 cases/week/120 dogs, during which time the culture prevalence was 23% for B. bronchiseptica in dogs and 47% in cats. Three to 6 months before the kennel-cough epidemic, no dogs or cats were B. bronchiseptica positive. Very little genetic variability was detected in isolates from these shelters; all isolates except one corresponded to a single strain type which was identical to the pattern in a vaccine used in these shelters. Isolates from other cats, a horse, a llama, and a sea otter were genetically distinct from the shelter isolates. There was widespread resistance to cephalosporins and ampicillin, but low or no resistance to amoxicillin/clavulanate, trimethoprim-sulfamethoxazole, tetracycline, and enrofloxacin. Greater percent resistance was observed in the traditional shelter than in the no-kill shelter and feline isolates were more likely to be resistant than canine isolates. 相似文献
7.
8.
9.
10.
Spatial analysis of the exposure of dogs in rural north-coastal California to vectorborne pathogens 总被引:1,自引:0,他引:1
Foley JE Brown RN Gabriel MW Henn J Drazenovich N Kasten R Green SL Chomel BB 《The Veterinary record》2007,161(19):653-657
Between 0 and 50 per cent of the dogs in eight rural villages in far northern California with a high risk of tickborne diseases were seropositive for Anaplasma phagocytophilum and Bartonella vinsonii subspecies berkhoffii, and between 0 and 10 per cent were seropositive for Borrelia burgdorferi. The odds ratio for the co-exposure of individual dogs to B vinsonii berkhoffii and A phagocytophilum was 18.2. None of the diseases was associated with the sex of the dogs, whether they slept out of doors, or whether tick-preventive measures were taken. When the villages were assessed for landscape risk factors, a particularly high seroprevalence for B vinsonii berkhoffii and A phagocytophilum was observed in a village at a relatively high altitude and greater distance from the Pacific coast, and montane hardwood conifer woodland was most associated with a high seroprevalence for these two pathogens. 相似文献