全文获取类型
收费全文 | 75篇 |
免费 | 23篇 |
专业分类
农学 | 1篇 |
基础科学 | 1篇 |
1篇 | |
综合类 | 4篇 |
农作物 | 3篇 |
畜牧兽医 | 86篇 |
植物保护 | 2篇 |
出版年
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 2篇 |
2017年 | 6篇 |
2016年 | 9篇 |
2015年 | 8篇 |
2014年 | 5篇 |
2013年 | 3篇 |
2012年 | 2篇 |
2011年 | 3篇 |
2010年 | 2篇 |
2009年 | 6篇 |
2008年 | 3篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 4篇 |
2003年 | 2篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1989年 | 3篇 |
1988年 | 2篇 |
排序方式: 共有98条查询结果,搜索用时 15 毫秒
91.
IA Zervos SN Lavrentiadou MP Tsantarliotou MP Georgiadis NA Kokolis IA Taitzoglou 《Reproduction in domestic animals》2010,45(6):e440-e446
Plasminogen activators (PA) are proteolytic enzymes present in the spermatozoa and seminal plasma of various species. They play a role in the binding of the spermatozoon and its penetration through the layers surrounding the oocyte. Plasminogen activator activity (PAA) is modulated by hormones that have a seasonal variation, such as testosterone and melatonin. The present study investigates the seasonal variation of PA activity in sperm extracts and seminal plasma of four farm animal species: boar, buck, bull and stallion. Semen samples were collected every second week during a 12‐month period and PAA was determined. With respect to sperm enzyme activity, the boar showed a peak from late January until the beginning of April, whereas the activity in the bull was at the highest levels from April until October and gradually declined during autumn and winter period. Plasminogen activator activity of stallion spermatozoa peaked during March and April, and remained low throughout the rest of the year, whereas in the buck sperm, PAA increased from late October until the end of January. No biologically significant variation was detected regarding the seminal PAA activity in any of the species studied. While seasonality of reproduction is typically studied from the female perspective, the present data provide compelling information about a factor that may affect the reproductive ability of the male. 相似文献
92.
93.
94.
Effects of Serum Deprivation and Cycloheximide on Cell Cycle of Low and High Passage Porcine Fetal Fibroblasts 总被引:1,自引:0,他引:1
MD Goissis HVA Caetano MG Marques FRO de Barros WB Feitosa MP Milazzotto M Binelli MEOA Assumpção JA Visintin 《Reproduction in domestic animals》2007,42(6):660-663
Arrest of cells in G0/G1 cell cycle phase is desired for nuclear transfer procedures. Serum starvation and cell cycle inhibitors are different ways to induce synchronization of the cell cycle. This study investigated the effects of serum starvation and cycloheximide (CHX) on the cell cycle of low (5th) and high (15th) passages fetal porcine fibroblasts. Cell cycle phases were determined using fluorescent activated cell sorting. Fifth passage fibroblast cultures had higher (p < 0.05) proportion of cells in G0/G1 only after 72 h of serum starvation (77.60 ± 0.65) when compared with non‐starved cells (71.44 ± 1.88). Serum starvation for all periods tested induced an increase (p < 0.05) on proportion of cells in G0/G1 on the 15th passage. No significant differences were observed on the 5th passage cultures exposed to CHX, although, on the 15th passage an increase on proportion of cells was observed after all periods of exposure (p < 0.05). These data indicates that high passage cells in vitro are more susceptible to serum starvation and CHX G0/G1 synchronization. 相似文献
95.
M Rodriguez F Marco-Jiménez JS Vicente MP Viudes-de-Castro 《Reproduction in domestic animals》2006,41(S2):105-105
In extensive systems, beef cows should be continuously with their calves to optimise pasture use but this practice can lengthen post-partum interval (PPI). A study was conducted to determine the influence of suckling frequency on Parda de Montaña cow-calf performance when cows are fed 70% energy requirements during lactation (outdoor winter conditions simulation). Thirty-six autumn-calving cows with similar body condition at calving (2.57) were assigned to three suckling systems [ ad libitum (AL), twice (2D) or once daily (1D) for 30 min]. Blood samples were collected twice a week to analyse progesterone concentrations by RIA. Cows lost similar weight until start of mating period (day 52 post-partum; −0.583, –0.513, –0.520 kg/day in AL, 2D and 1D). Standard milk yield was higher in AL than the rest (8.9, 6.2, 7.0 kg; p < 0.05), which was reflected on greater calf gain (0.895, 0.752, 0.676 kg/day; p < 0.05) and larger cow weight loss within 90 days post-partum in this treatment (–0.345, –0.188, –0.083 kg/day; p < 0.05). Suckling system did not affect either PPI (69.6, 89.1, 65.5 days) or cows cycling within 90 days post-partum (55, 46, 58%), which may compromise the target calving interval. In Parda de Montaña breed fed moderately pre-calving and undernourished during lactation, restricted suckling did not favour ovarian activity resumption, but post-partum subnutrition delayed about 40 days PPI observed in similar body condition at calving and calf management (Sanz et al., 2003; Anim Reprod Sci 79: 57–69) 相似文献
96.
Canine distemper virus (CDV) can cause mortality in domestic dogs, which is easily prevented by the consistent application of vaccination protocols. The aim of this study was to determine if the dog populations of three strategically located islands in the Torres Strait of Australia, adjacent to Papua New Guinea, are infected by CDV. Eighty-four serum samples were collected from 70 dogs resident on Saibai, Dauan and Boigu Islands during 2017–2018. Sera were tested for CDV antibodies by a virus neutralization test (VNT). Overall, 7 (8.3%) sera from 6 (8.6%) dogs resident on all three islands were test positive. VNT titres ranged from 20 to >1280. Male adult dogs were more commonly seropositive than female and juvenile dogs. Considering the origin and age of test positive dogs, and veterinary visits to these islands, it was concluded that there is evidence of exposure to a field strain of CDV – rather than previous vaccination – in 4 of the 70 dogs (5.7%) tested in this study. Given the strategic location of these islands in a zone of high biosecurity risk, ongoing surveillance of pathogens such as CDV could inform on potential disease spread pathways in this region. In addition, the presence of high serological titres in the apparent absence of clinical disease requires further investigation. 相似文献
97.
Canine parvovirus (CPV) has been reported throughout the world since the late 1970s. Published information was reviewed to draw insights into the epidemiology, pathogenesis, diagnosis, treatment and outcomes of CPV disease in Australia and the role of scientific research on CPV occurrence, with key research discoveries and knowledge gaps identified. Australian researchers contributed substantially to early findings, including the first reported cases of parvoviral myocarditis, investigations into disease aetiopathogenesis, host and environmental risk factors and links between CPV and feline panleukopenia. Two of the world's first CPV serological surveys were conducted in Australia and a 1980 national veterinary survey of Australian and New Zealand dogs revealed 6824 suspected CPV cases and 1058 deaths. In 2010, an Australian national disease surveillance system was launched; 4940 CPV cases were reported between 2009 and 2014, although underreporting was likely. A 2017 study estimated national incidence to be 4.12 cases per 1000 dogs, and an annual case load of 20,110 based on 4219 CPV case reports in a survey of all Australian veterinary clinics, with a 23.5% response rate. CPV disease risk factors identified included socioeconomic disadvantage, geographical location (rural/remote), season (summer) and rainfall (recent rain and longer dry periods both increasing risk). Age <16 weeks was identified as a risk factor for vaccination failure. Important knowledge gaps exist regarding national canine and feline demographic and CPV case data, vaccination coverage and population immunity, CPV transmission between owned dogs and other carnivore populations in Australia and the most effective methods to control epizootics. 相似文献
98.
HM Mutembei MP Kowalewski B Ugele G Schuler B Hoffmann 《Reproduction in domestic animals》2009,44(1):17-23
Oestrogens are essential for male fertility targeting the testicular-epididymal compartment. However, the underlying mechanisms are only vaguely known and species specificities must be considered. The boar has a remarkably high testicular-oestrogen output, with the biologically inactive oestrone-sulphate being the major oestrogen occurring in the testicular vein. In the boar testis and epididymis, activity of steroid sulphatase (StS) and oestrogen sulphotransferase has been demonstrated. Thus apart from their synthesis in Leydig cells, provision of biologically active free oestrone seems also to depend on the activity and localization of these enzymes. Our aim was to establish expression patterns and activity of StS in boar testis. Testes were randomly collected from healthy boars and allotted to five age groups, five animals in each, aged 50, 100, 150, 200 and 250 days. Three extra boars aged over 250 days were castrated to obtain fresh tissue for enzyme activity tests. Immunohistochemistry detected StS only in the cytoplasm of Leydig cells and – except for day-50 group in which 65.1 ± 4.9% (X ± SD) of the cells were positive – expression was constant with virtually all the cells staining positive. RT-PCR and in situ hybridization confirmed expression and localization of StS mRNA. The V max and K m value (X ± SD) for StS was 24.05 ± 0.3 fmol/s/μg protein and 2.15 ± 0.12 μ m . These data suggest that StS within the Leydig cells of the boar is involved in modulation of testicular oestrogen bioavailability and that the site of sulpho-conjugation is not the testis but a different compartment of the testes–epididymidis complex. 相似文献