全文获取类型
收费全文 | 129篇 |
免费 | 4篇 |
国内免费 | 1篇 |
专业分类
林业 | 4篇 |
农学 | 6篇 |
1篇 | |
综合类 | 28篇 |
农作物 | 1篇 |
畜牧兽医 | 89篇 |
园艺 | 1篇 |
植物保护 | 4篇 |
出版年
2021年 | 1篇 |
2019年 | 3篇 |
2018年 | 1篇 |
2016年 | 7篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 8篇 |
2012年 | 3篇 |
2011年 | 1篇 |
2010年 | 4篇 |
2009年 | 3篇 |
2008年 | 6篇 |
2007年 | 2篇 |
2006年 | 11篇 |
2005年 | 10篇 |
2004年 | 7篇 |
2003年 | 5篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1969年 | 1篇 |
1966年 | 1篇 |
1964年 | 1篇 |
1954年 | 1篇 |
1922年 | 1篇 |
1911年 | 1篇 |
排序方式: 共有134条查询结果,搜索用时 15 毫秒
31.
32.
During autumnal leaf senescence, leaf nitrogen in deciduous trees is translocated to storage sites, especially bark and xylem tissues. Proteins that accumulate in large amounts in bark and xylem in winter and are absent from these organs in summer are called storage proteins, and are believed to be vehicles for storing nitrogen reserves. These reserves are important for spring growth and help trees tolerate or recover from both abiotic and biotic stresses. Based on seasonal patterns of accumulation, we previously identified three storage proteins with molecular masses of 60, 19 and 16 kDa in bark tissues of 'Loring' peach (Prunus persica (L.) Batsch). To characterize the distribution of these proteins in different-aged tissues and to determine if they have any function other than nitrogen storage, we examined their seasonal distribution in bark tissues of current-year and 1-year-old shoots, scaffold branches, main trunks and 4-5-year-old roots of 'Loring' peach. Verification of protein identity was based on molecular mass and reactions with antibodies directed against each specific protein. Protein distribution was variable. For all three proteins, the greatest amount was present in mid-winter in current-year and 1-year-old shoots. These tissues also showed the greatest seasonal variation in the amount of protein present. The 16 kDa protein was present only in the youngest shoots, whereas the 19 kDa protein was present in all tissues examined. The 60 kDa protein was absent in root tissue. The amino acid composition and sequence of each protein were determined. The 60 kDa protein was identified as a dehydrin, and the 19 kDa protein appeared to be related to a family of allergen proteins in Rosaceous plants, some members of which are associated with pathogenesis-related proteins. The amino acid sequence of the 16 kDa protein appeared to have no homology with any proteins in the SwissProt database. Therefore, it is likely that the 16 kDa protein, in a strict sense, is a bark storage protein. Defining storage proteins solely by their pattern of accumulation and the extent to which they accumulate may not be a good functional definition. It is possible that storage proteins have functional roles in addition to nitrogen storage. 相似文献
33.
Amanda C. Schmidt Lauchlan H. Fraser Cameron N. Carlyle Eleanor R.L. Bassett 《Strength and Conditioning Journal》2012,65(3):292-298
Half of the world's land base is grazed by domesticated livestock. Because of the important functional role of ants in grasslands, it is important to understand the effect of livestock grazing on ant abundance and diversity. The objectives of this study were to examine the effect of cattle grazing and site productivity on the abundance, species richness, and species diversity of ants in Lac du Bois Grasslands Provincial Park, British Columbia, Canada. We hypothesized that the measured ant variables would be lowest in grazed areas and at low site productivity. Pitfall trapping was conducted at four sites: two at each low and high site productivity levels. At each site an ungrazed (fenced exclosure) and grazed transect was sampled during May, July, and August of 2008. Captured ants were preserved in ethanol and identified. Eight genuses of ants were collected: Tapinoma, Camponotus, Formica, Lasius, Aphaenogaster, Myrmica, Solinopsis, and Temnotharox. The mean number of ants per pitfall was higher at high site productivity sites that were grazed (15.10 ± SE) compared to high productivity sites ungrazed (3.28 ± SE); grazing at low productivity reduced numbers of ants from 5.07 (± 0.70 SE) to 2.20 (± 0.39 SE) (F = 21.806; P [ 0.001). Tapinoma sessile and A. occidentalis had the greatest numbers in the pitfall traps. Species richness (F = 23.330, P [ 0.001) and diversity (F = 11.764, P = 0.001) followed a similar trend. Because productivity and cattle grazing affect ant diversity and abundance, and ants impact ecosystem functioning, these factors should be considered in management of grasslands. 相似文献
34.
35.
An 8-month-old, crossbred dog, presented with a painful, swollen face. The problem was of 4 weeks duration and had not responded to antibiotics. A diagnosis of canine juvenile cellulitis was based on the clinical presentation and supportive cytological and histopathological changes. Attempts to identify canine distemper virus were not successful. Complete resolution occurred with glucocorticoid therapy. This is the first report of canine juvenile cellulitis in a dog of this age. 相似文献
36.
Efficacy of cyclosporin in the treatment of atopic dermatitis in dogs--combined results from two veterinary dermatology referral centres 总被引:1,自引:0,他引:1
Burton G Burrows A Walker R Robson D Bassett R Bryden S Hill A 《Australian veterinary journal》2004,82(11):681-685
OBJECTIVE: To evaluate the efficacy of cyclosporin in controlling the clinical signs associated with atopic dermatitis in dogs under Australian field conditions. DESIGN: A multicentre prospective clinical investigation of the use of cyclosporin in 41 dogs with atopic dermatitis. PROCEDURE: Dogs were treated with cyclosporin (5 mg/kg orally once daily with food) for 6 weeks. Four clinical parameters of severity of atopic dermatitis were measured on Day 0 and on Day 42 using a 0 to 4 scoring system. Individual variables were then combined to form a Global Score. Both client and clinician observed pruritus scores were combined to form a Pruritus Score. Pre- and post-treatment scores were statistically analysed. The difference in results between the two investigators was also recorded and analysed. RESULTS: All dogs showed a marked reduction in pruritus and erythema during the 6-week treatment period. All dogs showed a significant (P < 0.001) improvement in clinical lesion scores and Global Score (P < 0.001). The mean percentage improvement in Global Score from Day 0 to Day 42 was 83.9%. The mean percentage improvement in Pruritus Score from Day 0 to Day 42 was 83%. The medication was well tolerated. Side effects such as vomiting, diarrhoea and soft stools were observed in four dogs. Another four dogs developed bacterial pyoderma during the trial period. There was no significant difference in results between the two centres. CONCLUSION: Cyclosporin was well tolerated and efficacious in the symptomatic treatment of atopic dermatitis in dogs attending two veterinary dermatology referral centres in Australia, under Australian field conditions, when administered at 5 mg/kg/day for 6 weeks. 相似文献
37.
38.
Twenty-one cows from eight herds affected by Johne's disease were assigned to four groups: seven were not thriving and had persistent diarrhoea, six were not thriving and had intermittent diarrhoea, four were not thriving but did not have diarrhoea, and four were clinically normal. Postmortem, macroscopic lesions consistent with Johne's disease were identified in 17 of the cows and Mycobacterium avium subspecies paratuberculosis (MAP) was isolated from all of them. However, except for the fact that diarrhoea was correlated with the presence of lesions in the large intestine there was little correlation between the presence or absence of clinical signs and the lesions associated with Johne's disease. The tissue distribution of MAP was also poorly correlated with either the clinical signs or the lesions. The organism was widely distributed in 17 of the 21 cows, including three of the clinically normal animals, and was present in the mammary tissues of seven cows including two of the clinically normal animals. Three distinct histopathological patterns were observed in the affected intestines: infiltration of the lamina propria with giant cells, tuberculoid lesions, and lepromatous lesions; the lepromatous lesions were associated with extensive pathological changes. 相似文献
39.
J Christensen-Dalsgaard W Dappen SV Ajukov ER Anderson HM Antia S Basu VA Baturin G Berthomieu B Chaboyer SM Chitre AN Cox P Demarque J Donatowicz WA Dziembowski M Gabriel DO Gough DB Guenther JA Guzik JW Harvey F Hill G Houdek CA Iglesias AG Kosovichev JW Leibacher P Morel CR Proffitt J Provost J Reiter EJ Rhodes FJ Rogers IW Roxburgh MJ Thompson RK Ulrich 《Science (New York, N.Y.)》1996,272(5266):1286-1292
Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations. 相似文献
40.
: Infection with Angiostrongylus vasorum was diagnosed at necropsy on a dog that died from acute pulmonary haemorrhage, and on recovery of L1 larvae by Baermann examination of faeces from two dogs, one of which had abdominal pain and retroperitoneal haemorrhage, while the other had right-sided heart failure due to cor pulmonale. The presenting signs included syncope (one dog), exercise intolerance (two dogs), cough (two dogs), abdominal pain (one dog) and depression (one dog). One-stage prothrombin time and activated partial thromboplastin time were prolonged in two dogs, buccal mucosal bleeding time was prolonged in one dog and globulin was elevated in all three dogs. Two dogs were treated with fenbendazole and recovered. 相似文献