全文获取类型
收费全文 | 513篇 |
免费 | 60篇 |
专业分类
林业 | 29篇 |
农学 | 4篇 |
基础科学 | 1篇 |
77篇 | |
综合类 | 46篇 |
农作物 | 24篇 |
水产渔业 | 30篇 |
畜牧兽医 | 329篇 |
园艺 | 10篇 |
植物保护 | 23篇 |
出版年
2024年 | 3篇 |
2023年 | 14篇 |
2022年 | 6篇 |
2021年 | 27篇 |
2020年 | 28篇 |
2019年 | 34篇 |
2018年 | 25篇 |
2017年 | 24篇 |
2016年 | 27篇 |
2015年 | 17篇 |
2014年 | 19篇 |
2013年 | 25篇 |
2012年 | 33篇 |
2011年 | 23篇 |
2010年 | 24篇 |
2009年 | 21篇 |
2008年 | 28篇 |
2007年 | 25篇 |
2006年 | 30篇 |
2005年 | 20篇 |
2004年 | 13篇 |
2003年 | 13篇 |
2002年 | 17篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1996年 | 4篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1972年 | 1篇 |
1971年 | 7篇 |
1970年 | 1篇 |
1969年 | 3篇 |
1967年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有573条查询结果,搜索用时 15 毫秒
101.
Cutaneous pythiosis in beef calves 总被引:3,自引:0,他引:3
R I Miller B M Olcott M Archer 《Journal of the American Veterinary Medical Association》1985,186(9):984-986
Six Brahman and Brahman-cross calves less than or equal to 9 months old were examined because of ulcerative swellings of the fetlocks (5 calves) or numerous focal ulcerated cutaneous lesions (1 calf). Biopsies revealed focal cutaneous granulomas around regular, thick-walled branching hyphae, 4 to 9 micron in diameter. In all cases, portions of the hyphae were surrounded by granular encrustations, which ultrastructurally were composed of amorphous material comparable to antigen-antibody complexes. The protist Pythium sp was isolated from 2 calves. 相似文献
102.
Caitlin Riggs Lakshmi Narayanan Charlee Mulligan Robert Wills Andrew Mackin Claire Fellman John Thomason Todd Archer 《Journal of veterinary pharmacology and therapeutics》2019,42(4):385-391
Cyclosporine is a powerful T‐cell inhibitor used in the treatment of immune‐mediated and inflammatory diseases in the dog. There is limited information on how to best monitor patients on cyclosporine therapy. Currently, pharmacokinetic and pharmacodynamic assays are available. Pharmacokinetic assays that measure the concentration of cyclosporine in the blood are used to assess if an appropriate drug concentration has been achieved; however, target blood drug concentrations have not been shown to reliably correlate with suppression of T‐cell function in the dog. In human transplant recipients, therapeutic drug monitoring has shifted to include pharmacodynamic‐based monitoring. Our laboratory has validated a RT‐qPCR assay to measure the pharmacodynamic effects of cyclosporine in the dog. In this study, activated T‐cell expression of IL‐2 and IFN‐γ was measured using RT‐qPCR daily for 7 consecutive days in 8 healthy Walker hounds receiving oral cyclosporine at a dosage of 10 mg/kg every 12 hr. Cytokine production was found to be markedly decreased within 24 hr after the initiation of cyclosporine and remained significantly decreased for the duration of the project. Based on these results, cyclosporine causes a rapid drop in T‐cell cytokine production that is sustained with continued dosing in healthy dogs. Although performed in healthy dogs, this study demonstrated a marked decrease in cytokine suppression within 24 hr of drug administration, suggesting that pharmacodynamic monitoring of cyclosporine's effects on T cells could be considered within several days of commencing therapy in dogs suffering from life‐threatening immune‐mediated disorders. 相似文献
103.
104.
Emma L. Houck Eli B. Cohen Mandy Womble Gregory A. Lewbart Olivia A. Petritz 《Veterinary radiology & ultrasound》2019,60(5):473-484
Gastrointestinal disorders are an important cause of morbidity in box turtles (Terrapene carolina Carolina), however published information is currently lacking on the normal radiographic anatomy, transit, and emptying times of the gastrointestinal tract. A total of 15 healthy box turtles were recruited for this prospective, anatomic, reference interval study. Three‐view radiographic series (vertical beam dorsoventral, horizontal beam latero‐lateral, and horizontal beam rostrocaudal views) were acquired prior to contrast administration, and following contrast administration at 0, 20, 40, 60, and 90 min, 2, 4, 8, 12, and 24 h post administration, and every 24 h thereafter until all contrast was eliminated (15 mL/kg barium sulfate diluted to 30% weight per volume was administered via orogastric gavage). Vertical beam dorsoventral and horizontal beam latero‐lateral views were of excellent quality to identify gastrointestinal structures. The horizontal beam rostrocaudal view immediately postcontrast administration provided gastric and pyloric identification but had lesser diagnostic use at later time points due to anatomical superimposition. The gastrointestinal tract was composed of a tubular stomach, a pyloric sphincter near midline, a duodenum with a cranial flexure in the right cranial coelomic cavity, small intestines within the right coelom, a small cecal bulb, and a transverse and descending colon. Contrast media entered the large intestine by 24 h in all turtles, and a pyloro‐colic indentation was noted at the proximal descending colon. The large intestinal emptying was highly variable due to the interindividual variability of contrast sequestration within the cecal bulb. Findings from the current study serve as a reference on the gastrointestinal anatomy, transit, and emptying times in healthy eastern box turtles; and introduce a novel, horizontal beam, rostrocaudal view for gastrointestinal contrast studies in chelonians. 相似文献
105.
106.
Context
An increasing number of studies have investigated the impact of environmental heterogeneity on faunal assemblages when measured at multiple spatial scales. Few studies, however, have considered how the effects of heterogeneity on fauna vary with the spatial scale at which the response variable is characterised.Objectives
We investigated the relationship between landscape properties in a region characterised by diverse fire mosaics, and the structure and composition of avian assemblages measured at both the site- (1 ha) and landscape-scale (100 ha).Methods
We surveyed birds and calculated spatial landscape properties in sub-tropical woodlands of central Queensland, Australia.Results
Environmental heterogeneity, as measured by topographic complexity, was consistently important for bird species richness and composition. However, the explanatory power of topographic complexity varied depending on the spatial scale and the component of diversity under investigation. We found different correlates of richness within particular foraging guilds depending on the scale at which richness was measured. Extent of long-unburnt habitat (>10 years since fire) was the most important variable for the landscape-scale richness of frugivores, insectivores and canopy feeders, whereas environmental heterogeneity in the surrounding landscape was more important for site-scale richness of these foraging guilds.Conclusions
The response of species richness to landscape characteristics varies among scales, and among components of diversity. Thus, depending on the scale at which a biodiversity conservation goal is conceptualised—maximising richness at a site, or across a landscape—different landscape management approaches may be preferred.107.
108.
Prevention of post operative complications following surgical treatment of equine colic: Current evidence
下载免费PDF全文
![点击此处可从《Equine veterinary journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Changes in management of the surgical colic patient over the last 30 years have resulted in considerable improvement in post operative survival rates. However, post operative complications remain common and these impact negatively on horse welfare, probability of survival, return to previous use and the costs of treatment. Multiple studies have investigated risk factors for post operative complications following surgical management of colic and interventions that might be effective in reducing the likelihood of these occurring. The findings from these studies are frequently contradictory and the evidence for many interventions is lacking or inconclusive. This review discusses the current available evidence and identifies areas where further studies are necessary and factors that should be taken into consideration in study design. 相似文献
109.
Patrick J Pollock Ronan Doyle Emma Tobin Kate Davison John Bainbridge 《Journal of zoo and wildlife medicine》2008,39(3):476-479
A 9-yr-old female Bornean orangutan (Pongo pygmaeus pygmaeus) presented with a 48-hr history of depression, lethargy, anorexia, and mucoid discharge from the rectum. Clinical, radiographic, and ultrasonographic examination demonstrated the presence of multiple distended loops of intestine, intestinal adhesions, and free gas within the abdomen. During exploratory laparotomy, fibrinopurulent diffuse peritonitis as a result of a ruptured intrapelvic abscess with associated large bowel adhesions was evident. The abdomen was thoroughly lavaged, necrotic debris and abscess wall removed, and fibrinous adhesions disrupted. The orangutan was kept sedated for 48 hr to allow for intensive care. Six months later, when the orangutan presented with similar clinical signs, ultrasonographic examination demonstrated the presence of a pelvic abscess. The previous procedure was repeated with the addition of a hysterectomy. This report is the first documentation of long-term management following surgical intervention for internal abdominal abscessation and septic peritonitis in a great ape. 相似文献
110.