全文获取类型
收费全文 | 144篇 |
免费 | 4篇 |
专业分类
林业 | 6篇 |
28篇 | |
综合类 | 18篇 |
农作物 | 1篇 |
水产渔业 | 5篇 |
畜牧兽医 | 78篇 |
植物保护 | 12篇 |
出版年
2024年 | 2篇 |
2013年 | 2篇 |
2012年 | 4篇 |
2011年 | 3篇 |
2009年 | 2篇 |
2008年 | 3篇 |
2007年 | 4篇 |
2006年 | 6篇 |
2005年 | 9篇 |
2004年 | 7篇 |
2003年 | 5篇 |
2002年 | 4篇 |
2001年 | 6篇 |
2000年 | 5篇 |
1995年 | 7篇 |
1994年 | 3篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 6篇 |
1985年 | 2篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1980年 | 4篇 |
1978年 | 3篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1971年 | 1篇 |
1970年 | 3篇 |
1966年 | 1篇 |
1961年 | 2篇 |
1958年 | 1篇 |
1957年 | 1篇 |
1955年 | 1篇 |
1945年 | 1篇 |
1943年 | 1篇 |
1941年 | 1篇 |
1940年 | 1篇 |
1936年 | 2篇 |
1935年 | 1篇 |
1933年 | 2篇 |
1931年 | 1篇 |
1927年 | 1篇 |
1926年 | 1篇 |
1921年 | 2篇 |
1919年 | 1篇 |
1899年 | 1篇 |
排序方式: 共有148条查询结果,搜索用时 15 毫秒
141.
Primary kidney cell cultures were prepared from 68 three-day-old calves. Complete monolayers of these cultures were infected separately with viral diarrhea, infectious bovine rhinotracheitis, parainfluenza, and adenovirus 7 viruses. The yield of virus from all infected cultures was calculated by plaque titer assay after 2 to 4 days' incubation. The variation of virus yield was substantial between individual cultures. 相似文献
142.
Tulipani S Urpi-Sarda M Garcı́a-Villalba R Rabassa M López-Uriarte P Bulló M Jáuregui O Tomás-Barberán F Salas-Salvadó J Espı́n JC Andrés-Lacueva C 《Journal of agricultural and food chemistry》2012,60(36):8930-8940
Walnuts ( Juglans regia L.), hazelnuts ( Corylus avellana L.), and almonds ( Prunus dulcis Mill.) are rich sources of ellagitannins and proanthocyanidins. Gut microbiota plays a crucial role in modulating the bioavailability of these high molecular weight polyphenols. However, to date there are no studies evaluating the capacity to produce nut phenolic metabolites in subjects with metabolic syndrome (MetS), a pathology associated with an altered gut bacterial diversity. This study applied a LC-MS targeted approach to analyze the urinary excretion of nut phenolic metabolites in MetS subjects following 12 weeks of nut consumption, compared to sex- and age-matched individuals given a nut-free control diet. Metabolites were targeted in both hydrolyzed and nonhydrolyzed urine by LC-PDA-QqQ-MS/MS analysis, and identification of metabolites lacking available standards was confirmed by LC-ESI-ITD-FT-MS. Ellagitannin-derived urolithins A and B significantly increased after the nut-enriched-diet, urolithins C and D were also detected, and a complex combination of urolithin-conjugated forms was observed in nonhydrolyzed urine, confirming an extensive phase II metabolism after absorption. In contrast, no significant increases in proanthocyanidin microbial metabolites were observed in urine following nut consumption. Because the intestinal microbiota of the subjects in this study could catabolize ellagitannins into a wide range of urolithins, further research is strongly warranted on the in vivo potential of these microbial metabolites in reducing cardiometabolic risk. 相似文献
143.
Immunity to colon cancer assessed by antigen-induced inhibition of mixed mononuclear cell migration 总被引:2,自引:0,他引:2
A purified preparation of mixed human peripheral blood lymphocytes and monocytes was used in an inhibition-of-migration assay for cell-mediated immunity to cancer of the colon. This preparation was reproducibly antigen-responsive and migrated with greater reliability than did a more complex cell mixture. Of 27 patients with this disease, cells from 24 showed inhibited migratio in response to colon carcinoma antigen. Uninhibited migration patterns were found in each of the 52 cancer-free controls, including eight patients with nonmalignant disease initially diagnosed as cancer of the colon, and in nine patients with surgically cured adenocarcinoma of the colon. 相似文献
144.
145.
Larvae of the black swallowtail butterfly, Papilio polyxenes Stoll, forage successfully on plants that contain high levels of photosensitizing psoralens. These insects rapidly detoxify psoralens, particularly in the midgut tissue prior to absorption, with the result that appreciable levels of unmetabolized phototoxin do not enter the body circulation where deleterious light-induced interactions with dermal or subdermal tissues would occur. 相似文献
146.
147.
J. Ellis-Iversen F. Jorgensen S. Bull L. Powell A.J. Cook T.J. Humphrey 《Preventive veterinary medicine》2009,89(3-4):178-184
We investigated the associations between Campylobacter colonisation and management practices and farm characteristics in 603 housed broiler batches originating from 137 farms in Great Britain. All study batches were the initial batch slaughtered from the selected house on enrolled farms. Between 1 and 15 batches were sampled from each farm throughout the study. A total of 34.2% of the batches was Campylobacter positive and multivariable multilevel logistic regression revealed that the risk of Campylobacter colonisation was highest in July (OR = 3.4, CI95%:1.8; 6.4), August (OR = 3.4, CI95%:1.9; 6.2) and September (OR = 3.7, CI95%:1.9; 7.1). Cattle on or adjacent to the farm increased the risk (OR = 1.7, CI95%:1.1; 2.7), whereas chlorinated drinking water reduced it (OR = 0.5, CI95%:0.2; 0.9). If the first removed batch from the previous flock in the house had been Campylobacter positive, the first batch of the following flock was also more likely to be colonised (OR = 3.2, CI95%:2.1; 4.9). This association was more likely due to a persistent risk practice or source of Campylobacter on the farm than a direct carry-over from previous flock. 相似文献
148.
Olaf Schwab Thomas Maness Gary Bull Clive Welham Brad Seely Juan Blanco 《Forest Policy and Economics》2011,13(1):61-68
Assessing the impacts of cumulative, non-lethal damages to forests poses a particular challenge to forest management planning since cumulative merchantable volume losses are not known until the time of harvest. This paper introduces a model that scales stand-level processes to their large-scale implications by combining elements of growth and yield modeling, insect infestation modeling, and large-scale spatial harvest simulation. The model is described and tested using the proposed large-scale introduction of weevil-resistant spruce in British Columbia, Canada as a case study. While spruce weevil damages were found to be significant, only a relatively small percentage of losses can be avoided by planting resistant stock. The model introduced in this paper can serve as an important decision support tool for policy makers and researchers in assessing the large-scale effects of proposed policy and management interventions. 相似文献