全文获取类型
收费全文 | 134篇 |
免费 | 9篇 |
专业分类
林业 | 8篇 |
农学 | 12篇 |
24篇 | |
综合类 | 6篇 |
农作物 | 4篇 |
水产渔业 | 10篇 |
畜牧兽医 | 59篇 |
园艺 | 7篇 |
植物保护 | 13篇 |
出版年
2023年 | 4篇 |
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 5篇 |
2015年 | 1篇 |
2014年 | 6篇 |
2013年 | 4篇 |
2012年 | 11篇 |
2011年 | 15篇 |
2010年 | 3篇 |
2009年 | 4篇 |
2008年 | 8篇 |
2007年 | 7篇 |
2006年 | 4篇 |
2005年 | 7篇 |
2004年 | 4篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有143条查询结果,搜索用时 31 毫秒
71.
Andi Flory Lisa McLennan Betsy Peet Marissa Kroll Deirdre Stuart Devon Brown Kathy Stuebner Brenda Phillips Brenda L. Coomber J. Paul Woods Mairin Miller Chelsea D. Tripp Amber Wolf-Ringwall Kristina M. Kruglyak Angela L. McCleary-Wheeler Ashley Phelps-Dunn Lilian K. Wong Chelsea D. Warren Gina Brandstetter Michelle C. Rosentel Lauren R. DiMarzio Allison L. O'Kell Todd A. Cohen Daniel S. Grosu Jason Chibuk Dana W. Y. Tsui Ilya Chorny Jill M. Rafalko 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2023,37(1):258-267
72.
Lemos LS Siqueira de O dos Santos A Vieira-da-Motta O Texeira GN Queiroz de Carvalho EC 《Veterinary microbiology》2007,125(3-4):350-354
Cryptococcosis is considered a zoonosis but is rare in stock animals. In humans it is imputed to be a mortality cause in immunocompromised patients. This case study reports the anatomopathology of respiratory cryptococcosis in ovine and the recuperation and identification of Cryptococcus neoformans var. neoformans from 1-year frozen lung tissue sample. The findings from haematoxylin/eosin staining microscopy and special staining showed the destruction of the columnar respiratory epithelium architecture associated to suppuration, and the growth of spherical yeast buddings sometimes involved by clear halo produced by unstained capsular substance. The agent was identified by miniApi ID32C, while variety neoformans was further identified by culture in CGB agar. The diagnosis in stock animal suggests the involvement of an exogenous source of the agent as an alert to public health and contributes for epidemiological investigations. 相似文献
73.
Vandeweerd JM Davies JC Pinchbeck GL Cotton JC 《Journal of veterinary medical education》2007,34(2):160-167
Case-based e-learning may allow effective teaching of veterinary radiology in the field of equine orthopedics. The objective of this study was to investigate the effectiveness of a new case-based e-learning tool, compared with a standard structured tutorial, in altering students' knowledge and skills about interpretation of radiographs of the digit in the horse. It was also designed to assess students' attitudes toward the two educational interventions. A randomized, single-blinded, controlled trial of 96 fourth-year undergraduate veterinary students, involving an educational intervention of either structured tutorial or case-based e-learning, was performed. A multiple-choice examination based on six learning outcomes was carried out in each group after the session, followed by an evaluation of students' attitudes toward their session on a seven-point scale. Text blanks were available to students to allow them to comment on the educational interventions and on their learning outcomes. Students also rated, on a Likert scale from 1 to 7, their performance for each specific learning outcome and their general ability to use a systematic approach in interpreting radiographs. Data were analyzed using the Mann-Whitney test, the t-test, and the equivalence test. There was no significant difference in student achievement on course tests. The results of the survey suggest positive student attitudes toward the e-learning tool and illustrate the difference between objective ratings and subjective assessments by students in testing a new educational intervention. 相似文献
74.
Fry MM Walker NJ Blevins GM Magdesian KG Tablin F 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(3):359-362
A2-year-old Thoroughbred filly presented to the Veterinary Medical Teaching Hospital (VMTH) at the University of California, Davis, for evaluation of a bleeding disorder. The bleeding tendency was 1st noted 3 weeks before presentation on the morning after the horse was pin fired. Prolonged bleeding was noted after intramuscular injection of procaine penicillin G, and the trainer noted blood from the horse's right nostril 2 days before presentation. The filly had been seen by a referral practice, which found a prolonged prothrombin time but no other problems. The horse received an injection of vitamin K intravenously the day before presentation. The current owners purchased the horse ˜1 year before the initial bleeding episode, during which time she had not injured herself or had any intramuscular injections. The filly had received 1 dose PO of a dexamethasone (5 mg) and trichlormethiazide (200 mg) combinationa and 1 or 2 doses of phenylbutazone (unknown amount) but had not received aspirin. The exact dates of administration of these drugs were not known, but they were not within the week before presentation. She had never bled from venipuncture sites 相似文献
75.
Kerst Stelwagen Vicki C. Farr Gina D. Nicholas Stephen R. Davis Colin G. Prosser 《Livestock Science》2008,114(2-3):176-180
Forty mid-lactation, pasture-fed dairy cows were used to study the effects of milking interval on milk yield and quality and whether effects could be reversed during a short period of subsequent frequent milking. Following a 2-day pre-experimental period of normal twice-daily milking (TDM), cows were milked again after 6, 12, 18, 24 or 30 h, with each milking interval followed by 24 h of frequent milking (i.e., every 6 h). Milk yield increased linearly until 18 h and then started to plateau. Similarly, milk quality (serum albumin and proteolytic enzyme activity) became adversely affected after 18 h. These changes coincided with increased permeability of mammary tight junctions (TJ), starting after a milking interval of 18 h. A brief period of frequent milking helped restore milk yields to pre-experiment levels, even after the longest milking interval. 相似文献
76.
Survey of Fungicide Sensitivity in Colletotrichum gloeosporioides from Different Avocado and Mango Production Areas in South Africa 总被引:4,自引:0,他引:4
Gina M. Sanders L. Korsten F.C. Wehner 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(8):745-752
Pre-harvest fungicidal treatments aimed at reducing inoculum levels in the field include copper oxychloride and benomyl. Pre-harvest applications of benomyl are currently restricted if used on fruit destined for certain export markets. Isolates of Colletotrichum gloeosporioides collected during a three-year market survey were used to determine the incidence of resistance to benomyl, thiabendazole and prochloraz using an in vitro assay. A total of 17.7% of all isolates tested were resistant to benomyl, of which 8.5% were highly and 9.2% moderately resistant. Isolates from certain production areas were less sensitive to benomyl and thiabendazole, and mango isolates were generally more sensitive than avocado isolates. No isolates were resistant to thiabendazole or prochloraz. 相似文献
77.
78.
Many natural vegetation species have been shown to be negatively affected by ozone. This study has investigated how the presence of competing species in a community affects two common responses to ozone: visible injury and senescence. Monocultures and mixtures of Trifolium repens and Lolium perenne were grown in large containers and were exposed in solardomes to either a rural episodic ozone profile (AOT40 of 12.86 ppm h) or control conditions (AOT40 of 0.02 ppm h) for 12 weeks. The proportion of ozone-injured or senesced leaves was different in the different regions of the canopy. The highest proportions of injured/senesced leaves were in the plant material growing at the edge of the canopy and the upper canopy, with a significantly lower proportion of injured leaves in the inner canopy. The presence of L. perenne increased the proportion of ozone-injured leaves in T. repens at the final harvest, whilst the presence of T. repens decreased the proportion of senesced leaves in L. perenne. In L. perenne, the proportion of injured leaves at the edge and inner canopy decreased significantly when grown in competition, whilst for T. repens the reverse effect occurred in the inner canopy only. Different mechanisms appeared to influence the interaction between response to ozone and competitors in these two species. In L. perenne the response to ozone may have been related to nitrogen supply, whereas in T. repens canopy structure was more important. 相似文献
79.
Interleukin (IL)-8 and its receptors, CXCR1 and CXCR2, are key regulators of inflammation. However, knowledge of these receptors at the genomic level is limiting or absent in cattle. Therefore, our objective was to identify bovine orthologs of human CXCR1 and CXCR2. Alignment of bovine CXCR2 reference mRNA to the bovine genome revealed two regions of similarity on BTA2 approximately 20 kb apart and on opposite strands. Comparison with the human genome suggested the more centromeric region to be CXCR2 and the more telomeric region to be CXCR1 which contradicts the current annotation of the bovine CXCR2 reference mRNA. This observation was verified by sequencing RT-PCR products of specific regions within each predicted IL-8 receptor and comparing with human sequences using ClustalW. Further examination of coding and non-coding regions within the IL-8 receptor genome complex revealed that both bovine and canine CXCR1 and CXCR2 genes had more conserved sequences in common with the human genes than either mouse or rat, and may offer more suitable animal models for certain applications. This molecular information provides a stepping stone for greater understanding of the role each IL-8 receptor plays in inflammation and will enhance our ability to develop strategies against inflammatory based diseases. 相似文献
80.
Andres M. Agostinelli Anthony J. Clark Gina Brown-Guedira David A. Van Sanford 《Euphytica》2012,186(1):115-126
Fusarium head blight (FHB), or head scab, is an economically important disease of wheat (Triticum aestivum L.). In developing FHB-resistant soft winter wheat cultivars, breeders have relied on phenotypic selection, marker assisted
selection (MAS), or a combination of the two. The objectives of this study were to estimate heritability of resistance in
a resistant × susceptible cross and to simulate selection in order to determine the optimal combination of phenotypic and
genotypic selection. F2 derived lines from the cross of KY93C-1238-17-2 (high yielding, susceptible) × VA01W-476 (resistant line with two exotic
quantitative trait loci (QTL) and additional resistance) were grown under artificial inoculation in scab nurseries at Lexington
(2007 and 2008) and Princeton (2008), KY. Visual symptoms were estimated on a 1–3 scale; percentage Fusarium damaged kernels
(FDK), and deoxynivalenol (DON) concentration were measured. VA01W-476 contributed resistance alleles at two major QTL: Fhb1 and a QTL on chromosome 2DL, QFhs.nau-2DL. In this genetic background, the effect of QFhs.nau-2DL was more pronounced than that of Fhb1: 55 vs. 25% DON reduction and 40 vs. 32% FDK reduction. Genotypic selection based on both QTL was equivalent to phenotypic
selection of the most resistant 28% of the population for DON and the most resistant 24% of the population for FDK. We propose
that an initial round of phenotypic selection at moderate selection intensity will enrich the population with major QTL resistance
alleles while maintaining variation at minor scab resistance loci and for other traits in general. Genotyping can then be
used to extract lines whose phenotypic worth has been demonstrated and which are homozygous for resistance alleles at the
major QTL. 相似文献