全文获取类型
收费全文 | 610篇 |
免费 | 51篇 |
国内免费 | 3篇 |
专业分类
林业 | 42篇 |
农学 | 11篇 |
基础科学 | 1篇 |
141篇 | |
综合类 | 112篇 |
农作物 | 15篇 |
水产渔业 | 43篇 |
畜牧兽医 | 261篇 |
园艺 | 19篇 |
植物保护 | 19篇 |
出版年
2024年 | 2篇 |
2023年 | 11篇 |
2022年 | 13篇 |
2021年 | 20篇 |
2020年 | 20篇 |
2019年 | 25篇 |
2018年 | 25篇 |
2017年 | 29篇 |
2016年 | 15篇 |
2015年 | 24篇 |
2014年 | 21篇 |
2013年 | 32篇 |
2012年 | 51篇 |
2011年 | 68篇 |
2010年 | 25篇 |
2009年 | 19篇 |
2008年 | 33篇 |
2007年 | 30篇 |
2006年 | 27篇 |
2005年 | 34篇 |
2004年 | 21篇 |
2003年 | 28篇 |
2002年 | 17篇 |
2001年 | 7篇 |
2000年 | 8篇 |
1999年 | 5篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1972年 | 1篇 |
1971年 | 4篇 |
1970年 | 3篇 |
1969年 | 1篇 |
1967年 | 3篇 |
1965年 | 2篇 |
1964年 | 1篇 |
1960年 | 1篇 |
1957年 | 1篇 |
1948年 | 1篇 |
1941年 | 1篇 |
1918年 | 1篇 |
排序方式: 共有664条查询结果,搜索用时 15 毫秒
11.
Li SQ Zhang HQ Balasubramaniam VM Lee YZ Bomser JA Schwartz SJ Dunne CP 《Journal of agricultural and food chemistry》2006,54(3):739-746
Immunoglobulin-rich foods may provide health benefits to consumers. To extend the refrigerated shelf life of functional foods enriched with bovine immunoglobulin G (IgG), nonthermal alternatives such as high-pressure processing (HPP) may offer advantages to thermal processing for microbial reduction. To evaluate the effects of HPP on the immunoactivity of bovine IgG, a soymilk product enriched with milk protein concentrates, derived from dairy cows that were hyperimmunized with 26 human pathogens, was subjected to HPP or heat treatment. To achieve a 5 log reduction in inoculated Escherichia coli 8739, the HPP or heat treatment requirements were 345 MPa for 4 min at 30 degrees C or for 20 s at 70 degrees C, respectively. To achieve a 5 log reduction in natural flora in the enriched soymilk, the HPP or heat treatments needed were 552 MPa for 4 min at 30 degrees C or for 120 s at 78.2 degrees C, respectively. At equivalent levels for a 5 log reduction in E. coli, HPP and heat treatment caused 25% and no detectable loss in bovine IgG activity, respectively. However, at equivalent levels for a 5 log reduction in natural flora, HPP and heat resulted in 65 and 85% loss of bovine IgG activity, respectively. Results of combined pressure-thermal kinetic studies of bovine milk IgG activity were provided to determine the optimal process conditions to preserve product function. 相似文献
12.
Did incentives help municipalities recover from the Great Recession? Evidence from Midwestern cities
This study assesses the impacts of local business incentives in the largest urban areas of Illinois, Michigan, and Wisconsin, three Midwestern states that share similar histories and settings. We assembled a unique dataset combining information on two types of incentives, tax increment financing districts and tax abatements, together with socio‐economic, geographic, fiscal, and spatial competitive characteristics for all of the municipalities in six metropolitan areas. The outcome measures include employment growth, establishment formation, and business relocation. The analysis extends knowledge of the effects of economic development incentives in two ways. First, we improve upon previous research by incorporating key factors in municipal decisions to offer incentives. Second, we add to limited empirical evidence concerning local incentives following the Great Recession. Variation in the use of incentives reflects not only local decision‐making but also differing fiscal capacities and situations of adaptation to adverse economic conditions, with some governments pulling back on incentives and others initiating new approaches to retain or lure businesses. 相似文献
13.
14.
15.
16.
An adult Bengal tiger (Panthera tigris tigris) housed in an outdoor sanctuary in Florida exhibited vomiting, diarrhea, and weight loss. A clinical workup did not reveal the source of the clinical signs and antibiotic therapy was unrewarding. Radiographs revealed the presence of an abdominal mass. The tiger died during an immobilization for a follow-up clinical examination. A necropsy was performed and tissue samples of intestine and mesenteric lymph nodes were submitted for histopathologic diagnosis. A pyogranulomatous panenteritis and lymphadenitis with intralesional hyphae led to a presumptive etiologic diagnosis of intestinal/abdominal pythiosis. The diagnosis of pythiosis was confirmed by serology and immunoblotting. 相似文献
17.
R A Joshua 《Veterinary parasitology》1990,36(3-4):303-309
Quantitative methods were adopted to study the course of Trypanosoma congolense infection in mice and goats. The ease of initiating infection with a single organism (clone) was found to show a smooth correlation with the virulence of 24 isolates. Virulence of T. congolense was found to be directly related to the degree of viability of the parasite but inversely proportional to the capacity of the host to limit parasitaemia. Isolates obtained from the goat in the early stage of the infection were found to be highly infective but moderately virulent; subsequent isolates were of low infectivity and low virulence. Organisms obtained at the terminal stage of the infection were highly virulent. Generally, the highly virulent clones produced rapidly high parasitaemia and mortality in the host. The low virulence clones were characterised by low parasitaemia but very pronounced remission of trypanosomaemia. 相似文献
18.
19.
20.