全文获取类型
收费全文 | 406篇 |
免费 | 23篇 |
国内免费 | 1篇 |
专业分类
林业 | 20篇 |
农学 | 26篇 |
69篇 | |
综合类 | 14篇 |
农作物 | 84篇 |
水产渔业 | 39篇 |
畜牧兽医 | 147篇 |
园艺 | 3篇 |
植物保护 | 28篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 12篇 |
2020年 | 11篇 |
2019年 | 12篇 |
2018年 | 20篇 |
2017年 | 8篇 |
2016年 | 12篇 |
2015年 | 16篇 |
2014年 | 31篇 |
2013年 | 23篇 |
2012年 | 43篇 |
2011年 | 45篇 |
2010年 | 23篇 |
2009年 | 13篇 |
2008年 | 25篇 |
2007年 | 15篇 |
2006年 | 26篇 |
2005年 | 22篇 |
2004年 | 17篇 |
2003年 | 19篇 |
2002年 | 8篇 |
2001年 | 11篇 |
2000年 | 5篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1994年 | 1篇 |
1990年 | 1篇 |
1987年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有430条查询结果,搜索用时 187 毫秒
1.
Verification by polymerase chain reaction of vertical transmission of Theileria sergenti in cows 总被引:2,自引:0,他引:2 下载免费PDF全文
Byeong K. Baek Kim B. Soo Jin H. Kim Jin Hur Bou O. Lee J. M. Jung Misao Onuma Anthony O. Oluoch Chang-Hyun Kim Ibulaimu Kakoma 《Canadian journal of veterinary research》2003,67(4):278-282
To evaluate the transplacental transfer of Theileria sergenti infection in cattle, we used DNA probes to detect T. sergenti in 6 pregnant cows and their calves. All the animals were monitored by parasitologic, serologic, and polymerase chain reaction (PCR) assays for a predicted 875-base-pair (bp) DNA product and a 684-bp amplicon detected by nested PCR in the blood and spleens of aborted fetuses. An open reading frame (ORF) starting at nucleotide 170 and terminating at position 1021 was shown to code for a polypeptide of 283 amino acid residues. All 6 dams and 5 calves were positive for T. sergenti in all tests. One calf was positive only with nested PCR. We conclude that transplacental transmission of T. sergenti is a significant problem. The relevance of the data in the programmed introduction of new (especially pregnant) animals into established clean herds needs serious consideration with regard to control of theileriosis and other tickborne diseases. 相似文献
2.
Chang‐Hoon Shin Hien Thi Dieu Bui Samad Rahimnejad Ji‐Hoon Cha Byung‐Woo Yoo Bo‐Kyeun Lee Hyung‐Jin Ahn Soo‐Il Choi Yun‐Jeong Choi Yong‐Ho Park Jeong‐Dae Kim Kyeong‐Jun Lee 《Journal of the World Aquaculture Society》2014,45(3):258-268
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets. 相似文献
3.
Carbon nanotube (CNT) films are very flexible and serve as active materials for lithium-ion batteries (LIBs). Hence, they have high potential as flexible free-standing electrodes for wearable batteries. However, nanocarbon materials such as CNTs and graphene are of limited use as electrodes because they have a large initial irreversible capacity due to the formation of a solid electrolyte interphase (SEI). Herein, we prelithiated the CNT films to make them available as electrodes for flexible batteries by reducing their irreversible capacity. The SEI is pre-formed through a direct prelithiation (DP) method that brings lithium metal into direct contact with CNT films in an electrolyte. As a result, the capacity of directly-prelithiated CNT film electrodes continues to increase to 1520 mAh/g until 350th cycle of charge/discharge and their initial irreversible capacity vanishes. The changes in the electrochemical properties of CNT film electrodes by DP treatment and their flexibility are investigated. 相似文献
4.
Yeon Soo Chung Jae Won Song Dae Ho Kim Sook Shin Young Kyung Park Soo Jin Yang Suk Kyung Lim Kun Taek Park Yong Ho Park 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(2):199-206
Limited information is available regarding horse-associated antimicrobial resistant (AR) Escherichia (E.) coli. This study was designed to evaluate the frequency and characterize the pattern of AR E. coli from healthy horse-associated samples. A total of 143 E. coli (4.6%) were isolated from 3,078 samples collected from three national racetracks and 14 private horse-riding courses in Korea. Thirty of the E. coli isolates (21%) showed antimicrobial resistance to at least one antimicrobial agent, and four of the AR E. coli (13.3%) were defined as multi-drug resistance. Most of the AR E. coli harbored AR genes corresponding to their antimicrobial resistance phenotypes. Four of the AR E. coli carried class 1 integrase gene (intI1), a gene associated with multi-drug resistance. Pulsed-field gel electrophoretic analysis showed no genetic relatedness among AR E. coli isolated from different facilities; however, cross-transmissions between horses or horses and environments were detected in two facilities. Although cross-transmission of AR E. coli in horses and their environments was generally low, our study suggests a risk of transmission of AR bacteria between horses and humans. Further studies are needed to evaluate the risk of possible transmission of horse-associated AR bacteria to human communities through horse riders and horse-care workers. 相似文献
5.
6.
Heechun Lee Seongchan Yeon Hyojong Lee Dongwoo Chang Kidong Eom Junghee Yoon Hojung Choi Youngwon Lee 《Veterinary radiology & ultrasound》2005,46(4):317-318
A 7-year-old female Maltese presented for evaluation of severe vomiting. A diagnosis of pylorogastric intussusception was made during ultrasonographic examination. The intussusception spontaneously underwent reduction by the following morning. 相似文献
7.
A retrospective study was conducted to determine the relative frequency and type of elimination problem seen in dogs at a university referral practice and to evaluate the efficacy of the suggested treatments. Cases presented to the Animal Behavior Clinic at Cornell University between 1987 and 1996 were reviewed. Of 1,173 cases, 105 (9%) were house-soiling cases. Of these cases, the authors obtained outcome information from 70. Within the diagnosis of house soiling, incomplete housebreaking (n=59; 84%) were the most frequent referral cases, of which 48 cases (81%; 95% confidence interval, 69% to 90%) improved. Separation anxiety was considered the second most common underlying cause (n=27; 39%), of which 85% (n=23; 95% confidence interval, 66% to 96%) improved. Behavior modification was the most often suggested treatment (n=58), with 48 (83%) cases improving. Behavior modification consisted of accompanying the dog to the preferred elimination area, rewarding the dog for eliminating there, and punishing the dog only when caught in the act of house soiling. These results suggest that correct house training, behavior modification involving positive reinforcement, and appropriate punishment are essential to diminish house-soiling problems in dogs. 相似文献
8.
9.
Effects of chilled drinking water on the performance of lactating sows and their litters during high ambient temperatures under farm conditions 总被引:1,自引:0,他引:1
J.H. Jeon S.C. Yeon Y.H. Choi W. Min S. Kim P.J. Kim H.H. Chang 《Livestock Science》2006,105(1-3):86-93
Heat stress has detrimental effects on lactating sows and their litters, including decreased feed intake and milk production in sows and decreased weight gain in their offspring. It also increases respiration rate, rectal temperature, and weaning to estrus interval in sows. This study was conducted to investigate the effects of chilled water (CW) on the performance of lactating sows and their litters exposed to high ambient temperatures for 21 days. Ninety multiparous sows (Yorkshire × Landrace; parity range: 2 to 5) and their litters (Yorkshire × Landrace × Duroc) were divided into 3 blocks (30 each). Sows and their litters within each block were randomly assigned to one of the three treatment groups (n = 10 each). Each group was provided with drinking water at 10, 15, or 22 °C (control) under farm conditions where ambient temperature above 25 °C was consistent during the experimental period. Sows on CW (both 10 and 15 °C) consumed more feed and water than did control (P < 0.01) and higher estimated milk production compared with control (P < 0.01), but had lower rectal temperature and respiration rate compared with control (P < 0.01). Mean weaning weight (P < 0.01) and average daily gain (P < 0.01) of litters in CW groups were higher than those in control group. There were no differences in the measured variables, with the exception of the respiration rates, between the two CW treatment groups. These results suggest that CW may improve the performance of sows and their litters exposed to high ambient temperatures and the 15 °C water, from an energy viewpoint, may be more effective. 相似文献
10.
Marie Ren Gramer Jee Hoon Lee Young Ki Choi Sagar M. Goyal Han Soo Joo 《Canadian journal of veterinary research》2007,71(3):201-206
The H3N2 subtype of influenza A viruses isolated from pigs in the United States and Canada has shown both genetic and antigenic diversity. The objective of this study was to determine the serologic and genetic characteristics of contemporary strains of these viruses. Genetic analysis of 18 reference strains and 8 selected strains demonstrated differences in 1% to 9% of the nucleotides of the hemagglutinin (HA) gene. Phylogenetic analysis of the HA gene revealed 3 genetic clusters, as well as divergence of cluster III viruses from a cluster III prototype virus (A/Swine/Illinois/21587/99). By means of 1-way cross-hemagglutination inhibition with antiserum against 5 field isolates and 3 vaccine viruses, most of 97 isolates tested could be placed in 1 of 3 serogroups. The several isolates that did not react with any antiserum were in genetic cluster III, which suggests that continuous antigenic drift in cluster III may have resulted in virus variants. The efficacy of commercial vaccines against these virus variants should be evaluated with vaccination and challenge studies. 相似文献