首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   112篇
  免费   0篇
林业   3篇
农学   3篇
基础科学   1篇
  20篇
综合类   5篇
农作物   1篇
水产渔业   17篇
畜牧兽医   59篇
植物保护   3篇
  2023年   1篇
  2022年   2篇
  2021年   6篇
  2020年   4篇
  2019年   5篇
  2017年   1篇
  2016年   3篇
  2015年   6篇
  2014年   8篇
  2013年   5篇
  2012年   5篇
  2011年   14篇
  2010年   2篇
  2009年   2篇
  2008年   6篇
  2007年   8篇
  2006年   5篇
  2005年   5篇
  2004年   6篇
  2003年   9篇
  2002年   4篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1998年   1篇
  1983年   1篇
排序方式: 共有112条查询结果,搜索用时 10 毫秒
61.
A total of 57 Taylorella equigenitalis (n=22) and Taylorella asinigenitalis (n=35) isolates was shown not to carry any intervening sequences (IVSs) within 16S rRNA gene sequences. By contrast, we have already shown the genus Taylorella group to carry several kinds of IVSs within the 23S rRNA gene sequences.  相似文献   
62.
The fully ripened fruit of Katsura-uri Japanese pickling melon ( Cucumis melo var. conomon) has rarely been used for food because the midripened fruit is utilized for making pickles, but the fully ripened fruit is no longer valuable for pickles due to the fruit body being too soft. We have considered the utilization of the fully ripened Katsura-uri fruit that may be used for nonpickling products, particularly if the fully ripened fruit demonstrated health benefits such as anticarcinogenic properties. The phytochemical extract from the fully ripened fruit of Katsura-uri Japanese pickling melon was purified via a bioassay-guided fractionation scheme, which was based on the induction of differentiation in a RCM-1 human colon cancer cell line. On the criteria of two differentiation markers (duct formation and alkaline phosphatase activity), the most potent fraction contained a compound identified as 3-methylthiopropionic acid ethyl ester, based on GC retention time, EI-MS, (1)H NMR, and (13)C NMR spectra. Previously, the role of 3-methylthiopropionic acid ethyl ester was considered as an odor producing compound in many fruits, but this study indicates potential medical benefits of this compound.  相似文献   
63.
64.
Monomeric Plum (Plum), a far-red fluorescent protein with photostability and photopermeability, is potentially suitable for in vivo imaging and detection of fluorescence in body tissues. The aim of this study was to generate transgenic cloned pigs exhibiting systemic expression of Plum using somatic cell nuclear transfer (SCNT) technology. Nuclear donor cells for SCNT were obtained by introducing a Plum-expression vector driven by a combination of the cytomegalovirus early enhancer and chicken beta-actin promoter into porcine fetal fibroblasts (PFFs). The cleavage and blastocyst formation rates of reconstructed SCNT embryos were 81.0% (34/42) and 78.6% (33/42), respectively. At 36–37 days of gestation, three fetuses systemically expressing Plum were obtained from one recipient to which 103 SCNT embryos were transferred (3/103, 2.9%). For generation of offspring expressing Plum, rejuvenated PFFs were established from one cloned fetus and used as nuclear donor cells. Four cloned offspring and one stillborn cloned offspring were produced from one recipient to which 117 SCNT embryos were transferred (5/117, 4.3%). All offspring exhibited high levels of Plum fluorescence in blood cells, such as lymphocytes, monocytes and granulocytes. In addition, the skin, heart, kidney, pancreas, liver and spleen also exhibited Plum expression. These observations demonstrated that transfer of the Plum gene did not interfere with the development of porcine SCNT embryos and resulted in the successful generation of transgenic cloned pigs that systemically expressed Plum. This is the first report of the generation and characterization of transgenic cloned pigs expressing the far-red fluorescent protein Plum.  相似文献   
65.
An adult dairy cow fatally affected with winter dysentery was investigated pathologically and virologically. The cow had severe anemia and diarrhea with massive blood. Pathologically, the loss of surface epithelial cells and necrosis of crypt epithelial cells in the large intestine were observed. Bovine coronavirus (BCV) antigen was observed in necrotic crypt epithelial cells of the large intestine. Virus particles were found in the necrotic epithelial cells of the large intestine. Virologically, BCV was isolated from the feces of the dead cow. The dead cow had no serum antibody against BCV although the co-habitants did. These suggest that severe infection of BCV in the cow without the BCV antibody accompanied by severe hemorrhagic anemia resulted in the cow's death.  相似文献   
66.
Malachite green (MG) has been focused on as a biotreatment target and its biological properties have also been an issue in food fish aquaculture. An MG-removing bacterium was isolated from aquaculture fish pond sediment samples in Thailand. The isolate, strain T-5-2, is a Gram-negative, aerobic rod-shaped bacterium, and has been identified as a member of the Pseudomonas putida group. Proton nuclear magnetic resonance spectroscopy (1H-NMR) analysis of a broth culture medium containing MG showed that the concentration of MG decreased markedly and that other molecules, including leucomalachite green (LMG), were generated. Moreover, liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis showed that the MG concentration in the broth culture medium continuously decreased. This analysis also demonstrated that the concentration of LMG initially increased and then gradually decreased. Furthermore, gas chromatography–mass spectrometry (GC–MS) analysis showed 4-(dimethylamino)benzophenone (4DABP) as a degradation component of MG, which was confirmed by 1H-NMR and LC–MS/MS analysis. These findings suggest that this bacterial strain can remove MG in broth culture and degrade it to certain metabolites, including LMG and 4DABP. This study is the first detailed evaluation by the combination of LC–MS/MS, GC–MS, and 1H-NMR analyses of an MG-removing bacterium isolated from Thai aquaculture fish ponds.  相似文献   
67.
The present study examined the effects of high-concentration ascorbic acid (AsA) supplementation over a long period on growth, plasma components, nonspecific immune responses, and thermal tolerance in rainbow trout Oncorhynchus mykiss. Four commercial diets supplemented with 0, 100, 1000, and 5000 mg AsA per kg of diet (designated AsA0, AsA100, AsA1000, and AsA5000, respectively) were fed to rainbow trout (initial weight 1.85 g) for 100 days. AsA contents in liver increased with increasing dietary AsA levels. Feeding period, growth performance, and plasma components did not differ significantly between the AsA groups. On the other hand, the phagocytic assay [nitro-blue tetrazolium (NBT) assay] was significantly higher in fish fed AsA1000 and AsA5000 than those fed a diet without AsA (AsA0) at the end of feeding trial. Superoxide dismutase (SOD) activity in the intestines of fish fed AsA5000 was also significantly higher than that of fish fed AsA0. In the thermal tolerance test, fish fed AsA5000 only showed significantly lower cumulative mortality compared with the AsA0 group. In conclusion, high-concentration AsA supplementation such as AsA5000 over a long period does not induce any adverse effects and can enhance disease and stress resistance in rainbow trout.  相似文献   
68.
The Japanese eight-barbel loach Lefua echigonia, which is a freshwater fish native to Japan, is distributed from the Tohoku to Kinki districts and is divided into six regional populations according to mtDNA analysis. In this study, we investigated L. echigonia collected from several locations in Yamagata Prefecture and neighboring prefectures using mtDNA control region sequences and confirmed the spatial distribution pattern among the new regional population (Yamagata population). The new population was limited to the Mogami river system in the inland area of Yamagata Prefecture and is distinguished from other regional populations by high sequence divergences.  相似文献   
69.
A. Hitomi    H. Amagai  H. Ezura 《Plant Breeding》1998,117(4):379-383
Somaclonal variation is a possible source of variation in plant breeding. To apply this approach to eggplant breeding, somaclonal variations were observed among plants regenerated through somatic embryogenesis induced by 1-naphthaleneacetic acid (NAA) or 2,4-dichlorophenoxyacetic acid (2,4-D). Variations including leaf shape, plant height, flower number per cluster, fruit shape, anther number per flower and pollen fertility were compared among ? 300 plants (R0). Although these variations were confirmed among plants regenerated using both auxins, the frequencies of somaclonal variations in leaf shape, plant height, fruit shape and pollen fertility in the NAA experiment were higher than those in the 2,4-D experiment. Variations in flower number and anther number were also confirmed among plants from both experiments, although no significant differences in their frequency were observed. Subsequently, the inheritance of variations (leaf shape, fruit shape, and flower number) observed in R0 was investigated from generation to generation (R1). Variations in leaf shape and fruit shape were inherited while those in flower number were not. From these results we concluded that, although a high frequency of somaclonal variations were observed among plants from both methods, embryogenesis with NAA was more efficient than 2,4-D in eggplant.  相似文献   
70.
Isono  Chiaki  Maruta  Hitomi  Ma  Yun  Ganeko  Natsuki  Miyake  Tsuyoshi  Yamashita  Hiromi 《Fisheries Science》2020,86(6):1087-1099
Fisheries Science - The proximate composition and nutritional content of oysters define their quality and commercial value. Cultivation site and harvest date may impact these characteristics. We...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号