全文获取类型
收费全文 | 147篇 |
免费 | 15篇 |
专业分类
林业 | 22篇 |
农学 | 13篇 |
33篇 | |
综合类 | 10篇 |
农作物 | 7篇 |
水产渔业 | 7篇 |
畜牧兽医 | 57篇 |
园艺 | 5篇 |
植物保护 | 8篇 |
出版年
2023年 | 2篇 |
2022年 | 7篇 |
2021年 | 10篇 |
2020年 | 7篇 |
2019年 | 19篇 |
2018年 | 16篇 |
2017年 | 9篇 |
2016年 | 9篇 |
2015年 | 12篇 |
2014年 | 8篇 |
2013年 | 9篇 |
2012年 | 6篇 |
2011年 | 8篇 |
2010年 | 7篇 |
2009年 | 5篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 4篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1997年 | 1篇 |
1990年 | 1篇 |
排序方式: 共有162条查询结果,搜索用时 12 毫秒
151.
Sliwa E Adaszek Ł Tatara M Dobrowolski P 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(9-10):397-405
The aim of this study was to investigate short-term 4 and 14 weeks after fundectomy) and long-term (at the age of 8 months) postoperative effects of 3-hydroxy-3-methylbutyrate and/or alpha-ketoglutarate on selected serum biochemical markers in fundectomized pigs. Experimental fundectomy was performed in 30 castrated male pigs of the Pu?awska breed who received placebo or 3-hydroxy-3-methylbutyrate and/or alpha-ketoglutarate up to the age of 8 months. Plasma amino acid concentrations and selected blood parameters were analyzed. Main vital organs were weighed. Our study showed that the supplementations with alpha-ketoglutarate and/or 3-hydroxy-3-methylbutyrate to fundectomized pigs significantly prevented the reduction of stomach, liver and spleen weights. However, results of this study, either positive or negative, cannot categorically establish a beneficial effect of AKG and HMB nutritional support after fundectomy in pigs. 相似文献
152.
Joanna Paczuska Zdzis?aw Kie?bowicz Marcin Nowak Agnieszka Antończyk Rafa? Ciaputa Jakub Nicpoń 《Acta veterinaria Scandinavica》2014,56(1):1
Background
Tumors of the skin and subcutaneous tissue are the largest group of canine neoplasms. Total excision is still the most effective method for treatment of these skin tumors. For its universal properties the carbon dioxide (CO2) laser appears to be an excellent surgical instrument in veterinary surgery. Laser techniques are alternatives to traditional methods for the surgical management of tumors. The aim of this study was to compare various types of laser techniques in skin oncologic surgery: excision, ablation and mixed technique and to suggest which technique of CO2 laser procedure is the most useful in particular case of tumors in dogs.Findings
The study was performed on 38 privately-owned dogs with total number of 40 skin tumors of different type removed by various CO2 laser operation techniques from 2010–2013. The treatment effect was based on the surgical wound evaluation, the relative time of healing and possible local recurrence of the tumor after 3 months post surgery. Local recurrence was observed in two cases. The study showed that in 30 cases time needed for complete resection of lesions was less than 10 minutes. Time of healing was longer than 12 days in 6 cases (42.8%) with tumor excision and in 14 cases (87.5%) where excision with ablation technique was performed.Conclusions
The advantages of the CO2 laser surgery were better hemostasis, precision of working, non-contact dissection, less instruments at the site of operation and minimum traumatization of the surrounding tissues. 相似文献153.
Developmental competence of eggs produced by rainbow trout Doubled Haploids (DHs) and generation of the clonal lines 下载免费PDF全文
Krzysztof Jagiełło Stefan Dobosz Tomasz Zalewski Marcin Polonis Konrad Ocalewicz 《Reproduction in domestic animals》2018,53(5):1176-1183
Poor quality eggs produced by the fully homozygous doubled haploids (DHs) may impair generation of clonal lines in fish species. In the present research, gynogenetic development of rainbow trout (Oncorhynchus mykiss) was induced in eggs originated from the DH females. Eggs were activated with the UV‐irradiated grayling (Thymallus thymallus) spermatozoa and subjected to the high hydrostatic pressure (HHP) shock to provide diploid clonal individuals. Only two of four DH females produced eggs that were successfully activated by the irradiated spermatozoa and subsequently developed into the gynogenetic embryos. Survival rates of rainbow trout from the clonal lines equalled 21.5% and 19.8% during embryogenesis and decreased after hatching to 18.6% and 14.9%, respectively. Some of the dead rainbow trout clones collected between hatching and swim‐up stage were emaciated and exhibited spinal deformities including scoliosis. Provided results confirmed limited developmental competences of eggs produced by rainbow trout DH females. Clonal rainbow trout developing in such eggs exhibited reduced survival and increased frequency of the body abnormalities. 相似文献
154.
Robert Jankowiak Beata Strzałka Piotr Bilański Magdalena Kacprzyk Karolina Lukášová Riikka Linnakoski Sebastian Matwiejczuk Marcin Misztela Robert Rossa 《European Journal of Forest Research》2017,136(5-6):939-956
Bark beetles (Coleoptera: Curculionidae, Scolytinae) are commonly recognised as important agents of tree mortality in coniferous forests of the Western Carpathians. They, together with weevils, are consistently associated with ophiostomatoid fungi. Information regarding conifer beetle-associated fungi in the Western Carpathians remains incomplete and unreliable, particularly with respect to fir-infesting bark beetles. This study aims to clarify associations between fungi in the genera Graphilbum, Leptographium, Ophiostoma and Sporothrix (Ophiostomatales) and their beetle vectors in Norway spruce (Picea abies), European larch (Larix decidua) and silver fir (Abies alba). Samples associated with 20 bark beetle species and weevils were collected from nine stands in Poland and the Czech Republic. Fungi were isolated from adult beetles and galleries. Isolates were identified based on morphology, DNA sequence comparisons for four gene regions (ITS, LSU, ß-tubulin, TEF 1-α) and phylogenetic analyses. In total, 46 distinct taxa were identified, including 25 known and 21 currently unknown species. Several associations between fungi and subcortical insects were recorded for the first time. In addition, O. borealis and O. quercus were detected from A. alba for the first time. The composition of the fungal communities varied among the studied tree species and to a lesser degree among the beetle species. The spruce-infesting bark beetles were commonly associated with species of Leptographium s. l. and Ophiostoma s. str.; the larch-infesting bark beetles were often associated with Ophiostoma s. str. and Sporothrix, while the fir-infesting bark beetles were commonly associated with Ophiostoma s. str. and Graphilbum. The most commonly encountered fungal associates of the examined insects were (a) Grosmannia cucullata, G. piceiperda, Grosmannia sp. 1, Ophiostoma macroclavatum and O. piceae with the spruce-infesting bark beetles; (b) O. pseudocatenulatum and Sporothrix sp. 1 with the larch-infesting bark beetles; and (c) O. piceae, Ophiostoma sp. 2 and Graphilbum sp. 2 with the fir-infesting bark beetles. The differences in fungal associates among the bark beetle species occurring on P. abies, L. decidua and A. alba could be linked to the different habitats that these beetles occupy. 相似文献
155.
156.
Sylwia Prochowska Wojciech Nizanski Agnieszka Partyka Joanna Kochan Wiesawa Modawska Agnieszka Nowak Jzef Skotnicki Teresa Grega Marcin Pays 《Reproduction in domestic animals》2019,54(4):719-726
The aim of this study was to examine the suitability of commercial media designed for humans and cattle for oocyte maturation and embryo culture in the domestic cat. In Exp. I, feline oocytes collected ex vivo were subjected to in vitro maturation in a laboratory‐made culture medium (based on M199) or a commercial medium designed for cattle cells (BO‐IVM®). In Exp. II, ICSI‐derived feline embryos were cultured for 7 days in a commercial human (Continuous Single Culture®) or bovine (BO‐EC®) cell medium. The rates of cleavage, morula and blastocyst formation were evaluated at 24 hr, 6 days and 7 days after ICSI, respectively, and compared between experimental groups. At the end of culture, embryos were assessed for viability and apoptotic changes. In Exp. I, no statistically significant difference in oocyte maturation outcome between laboratory‐made (52.7%) and commercial media (58.9%) was observed. However, the use of a commercial medium prepared for use with bovine cells resulted in a significantly lower variance of the maturation rate. In Exp. II, no statistically significant differences between two commercial media were observed for cleavage (67.5% and 64.5%), morula (39.3% and 47.1%) and blastocyst rates (25.0% and 19.6%), as well as for the percentage of late apoptotic blastomeres. Morulae cultured in medium marketed for humans exhibited significantly more early apoptotic (43.2 ± 31.2% vs. 23.4 ± 23.2%) and necrotic (60.6 ± 47.6% vs. 29.4 ± 22.6%) blastomeres. In conclusion, both commercial media tested are suitable for in vitro oocyte maturation and embryo culture procedures in cats. It is remarkable that a culture medium designed for use in cattle for in vitro maturation of cat oocytes provides more reproducible results. 相似文献
157.
158.
Liv Østrem Marcin Rapacz Marit Jørgensen Mats Höglind 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):153-163
Abstract Changes in non-structural carbohydrates before and during winter are one of the major plant responses to winter stress. However, the observed pattern of changes is variable, not only between grass species but also between different experiments. This study examined the effect of developmental stage on carbohydrate reserves during winter in two grass species differing in winter hardiness. Timothy (Phleum pratense L.) and perennial ryegrass (Lolium perenne L.), sown early or late in the growing season, were sampled for total non-structural carbohydrates (TNC) in late October (end of main growing season), and then in late January, early March and late April. Quantitative and qualitative patterns of carbohydrate accumulation in crown segments were influenced both by plant genotype and developmental stage of the plants prior to winter. TNC increased from October to March, demonstrating considerable cell activity during winter, and declined to their lowest level in April. Sucrose proved to be the major reserve carbohydrate, followed by fructans. The highest content of TNC was found in the most winter-hardy cultivars, particularly in January and March. Early-sown plants accumulated higher levels of fructans than of sucrose, whereas late-sown plants mainly accumulated sucrose. These differences persisted during the winter. It can be concluded that the pattern of carbohydrate accumulation during winter differed between the two species studied and it was strongly affected by both cultivar and plant-developmental stage. 相似文献
159.
Hiroyuki Sato Makoto Miura Takeshi Fujieda Marcin Taciak Motoi Kikusato Kan Sato Masaaki Toyomizu 《Animal Science Journal》2021,92(1):e13605
Seventy-five individually fed barrows averaging 35 kg were used in a series of three experiments for 6-week growth assays (25 barrows each) to determine the effects of l -tryptophan (Trp) supplementation on growth performance and to establish the lower limits of dietary crude protein (CP) levels. Corn and soybean meal (SBM)-based diets containing 9% (Experiment 1), 10% (Experiment 2), and 11% CP (Experiment 3) fortified with deficient essential amino acids (AAs) except Trp were used as basal diets for each experiment. The experimental diets were supplemented with 0.00%, 0.02%, 0.04%, or 0.06% Trp. A 16% CP corn–SBM-based diet was set as a positive control in each experiment, and feed and water were provided ad libitum. Average daily gain and gain-to-feed ratio improved quadratically (P < 0.05) as supplemented Trp increased in the 9% and 10% CP group, although these positive effects were not observed in the 11% CP group. Because the maximum performance parameters in 9%, 10%, and 11% CP groups were not different from that of the 16% CP positive control group, the marginally reduced level of dietary CP without growth performance being affected appears to be around 9% at most. A potential reduction of nitrogen intake was clearly indicated. 相似文献
160.
Michał Czopowicz Olga Szaluś‐Jordanow Marcin Mickiewicz Agata Moroz Lucjan Witkowski Iwona Markowska‐Daniel Daria Reczyńska Emilia Bagnicka Jarosław Kaba 《Animal Science Journal》2018,89(9):1364-1370
We carried out this study to determine for how long small ruminant lentivirus (SRLV)‐specific antibodies can be detected by three commercial ELISA kits in goat kids after suckling infected does in field conditions. Forty‐one kids born to SRLV‐seropositive asymptomatic does were blood sampled prior to colostrum consumption, and then weekly for 6 months in total. The sera were screened with three commercial ELISA kits: whole‐virus ELISA (wELISA), recombinant transmembrane and capsid antigen ELISA (TM/CA‐ELISA), and surface antigen ELISA (SU‐ELISA). All but one kid were seronegative in all three ELISAs right after birth. At the age of 1 week all kids turned seropositive in wELISA, 39 kids (95%) in TM/CA‐ELISA, and 35 kids (85%) in SU‐ELISA. All seropositive kids turned seronegative in wELISA by the 15th week, and in SU‐ELISA by the 19th week (median of 8 weeks in both ELISA), whereas in TM/CA‐ELISA five kids (13% of 39 initially seropositive) were still seropositive at the age of 6 months (median of 11 weeks). Antibody levels at the age of 1 week proved significantly linked to the duration of maternal antibodies in all three ELISAs and could be employed to predict for how long maternal antibodies would remain detectable. 相似文献