全文获取类型
收费全文 | 92篇 |
免费 | 4篇 |
国内免费 | 2篇 |
专业分类
林业 | 7篇 |
农学 | 1篇 |
基础科学 | 8篇 |
7篇 | |
综合类 | 10篇 |
农作物 | 10篇 |
水产渔业 | 10篇 |
畜牧兽医 | 41篇 |
植物保护 | 4篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 5篇 |
2014年 | 1篇 |
2013年 | 7篇 |
2012年 | 7篇 |
2011年 | 9篇 |
2010年 | 1篇 |
2009年 | 3篇 |
2008年 | 4篇 |
2007年 | 11篇 |
2006年 | 6篇 |
2005年 | 1篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1993年 | 1篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有98条查询结果,搜索用时 15 毫秒
71.
An ovarian enlargement (diameter, 8 cm) was identified and surgically excised from a 5-year-old female dog. Microscopic examination of the multinodular neoplasm revealed sheets of polygonal neoplastic cells with large nuclei, frequent mitosis, necrosis and haemorrhage. Immunohistochemically, the neoplastic cells were positive for vimentin and alkaline phosphatase but were negative for CD3, CD79a, cytokeratin, alpha-fetoprotein, inhibin-α and S-100. The histopathological diagnosis of the mass was unilateral ovarian dysgerminoma. 相似文献
72.
Hanji (Korean traditional paper) yarn displays excellent humidity control, air permeability, and absorbency as well as pleasantness to the touch due to its structural characteristics, and thus, it has been developed as a new eco-friendly fibrous materials. In this study, Hanji, having a basis weight of 8 and 10 g/m2, was prepared using mulberry fibers. The prepared Hanji was cut into Hanji tape of 5–10 mm in width using a rotary slitter and then the tape was twisted to manufacture Hanji yarn. To ensure a uniform twist of Hanji yarn and a smooth twisting process, a water supply system was designed to provide water directly at the twisting zone. At a fixed spindle speed, the feeding speed of the delivery roller was varied to provide different twist numbers for the Hanji yarn. The Hanji yarn manufactured with water treatment has higher tensile properties and a softer touch than the Hanji yarn prepared without water treatment. The Hanji yarns have count numbers of 7–11 Ne and tensile strengths of 1.0–1.2 gf/d. Moreover, the fabric from Hanji yarn shows an excellent color fastness of 4.0 grade, staining of 4–5 to washing, and 4–5 grade to dry cleaning. 相似文献
73.
基于CBERS-02B卫星影像光谱信息的水稻种植面积提取方法——以南京市溧水县为例 总被引:2,自引:0,他引:2
利用水稻成熟期的影像,在进行光谱信息的统计和分析的基础上,对比水稻与其他植被在各波段DN(digital number)值以及NDVI(normalized difference vegetable index)值的数值差异,总结出水稻与其他植被反射光谱特征,认为成熟期的水稻在红光、绿光、蓝光波段DN值以及NDVI值上具有异于其他植被的特征,并通过波段运算扩大其数值差异,建立水稻像元提取模型,确定阈值,从而进行水稻种植面积的提取,精度可达91.95%。该方法能满足小区域的水稻种植面积提取和制图,并能够满足一定的精度要求。 相似文献
74.
Bhuiyan MM Cho J Jang G Park E Kang S Lee B Hwang W 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(3):257-261
The objective of this study was to determine if the transfection of human prourokinase (ProU) gene and passage number of transfected ear fibroblasts affected in vitro development of bovine transgenic nuclear transfer (NT) embryos. An expression plasmid for human ProU was constructed by inserting a bovine beta-casein promoter, a green fluorescent protein (GFP) marker and human ProU gene into a pcDNA3 plasmid and transfected into bovine ear fibroblasts using a lipid mediated method. Abattoir derived oocytes were enucleated at 18-20 hr post maturation and a single donor cell was transferred into the perivitelline space of a recipient oocyte. After fusion and activation, the couplets were cultured in modified synthetic oviductal fluid (mSOF) medium for 168 hr. In Experiment 1, significantly lower rate in blastocysts formation (10.3%) was observed in transfected donor cells at early passage than that in nontransfected counterparts (22.1%, P<0.05). In Experiment 2, development to blastocysts and GFP expression in blastocysts were not significantly different between early (3-7) and late (8-12) passage donor cells (10.3 vs. 11.3% and 54.5 vs. 41.7%, respectively). This study indicates that in vitro development of bovine transgenic NT embryos is negatively influenced by transfection of human ProU gene into donor fibroblasts. However, passage number of transfected ear fibroblasts does not affect in vitro development of bovine transgenic NT embryos. 相似文献
75.
Hwan Goo Kang Sang Hee Jeong Myung Haing Cho Joon Hyoung Cho 《Journal of veterinary science (Suw?n-si, Korea)》2007,8(4):361-368
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants present in air and food. Among PAHs, benzo(a)pyrene(BaP), phenanthrene (PH) and pyrene (PY) are considered to be important for their toxicity or abundance. To investigate the changes of biomarkers after PAH exposure, rats were treated with BaP (150 µg/kg) alone or with PH (4,300 µg/kg) and PY (2,700 µg/kg) (BPP group) by oral gavage once per day for 30 days. 7-ethoxyresorufin-O-deethylase activity in liver microsomal fraction was increased in only BaP groups. The highest concentration (34.5 ng/g) of BaP, was found in muscle of rats treated with BaP alone at 20 days of treatment; it was 23.6 ng/g in BPP treated rats at 30 days of treatment. The highest PH concentration was 47.1 ng/g in muscle and 118.8 ng/g in fat, and for PY it was 29.7 ng/g in muscle and 219.9 ng/g in fat, in BPP groups. In urine, 114-161 ng/ml 3-OH-PH was found, while PH was 41-69 ng/ml during treatment. 201-263 ng/ml 1-OH-PY was found, while PH was 9-17 ng/ml in urine. The level of PY, PH and their metabolites in urine was rapidly decreased after withdrawal of treatment. This study suggest that 1-OH-PY in urine is a sensitive biomarker for PAHs; it was the most highly detected marker among the three PAHs and their metabolites evaluated during the exposure period and for 14 days after withdrawal. 相似文献
76.
Konishi K Sakata Y Miyazaki N Jia H Goo YK Xuan X Inokuma H 《Veterinary parasitology》2008,155(3-4):204-208
A nationwide epidemiological survey of Babesia gibsoni infection in non-fighting dogs was conducted using an improved ELISA with recombinant B. gibsoni thrombospondin-related adhesive protein (BgTRAP). A total of 1206 dogs from 27 prefectures were examined and 128 (10.6%) tested positive. In the eastern part of Japan, 39 dogs out of the 559 (7.0%) examined were positive, while 89 dogs out of 647 (13.8%) tested positive in the western part of Japan. Although the percentage of dogs that tested positive was significantly (p=0.0001) lower in the eastern part compared to the western part of Japan, overall these results indicate that B. gibsoni infection of dogs has a widespread geographic distribution throughout the country. A history of tick infestation was identified as a significant risk factor for B. gibsoni infection (p=0.0091), while sex (p=0.9411), age (p=0.0920) and breed (p=0.0549) of dogs were not statistically significant risk factors. These results indicate that tick infestation is the most dominant risk factor for B. gibsoni infection of non-fighting dogs in Japan and suggest that other B. gibsoni transmission routes, such as fighting and transplacental transmission, may be less important. 相似文献
77.
78.
Ji-Yei CHOI Jung-Taek KANG Sol-Ji PARK Su-Jin KIM Joon-Ho MOON Islam M. SAADELDIN Goo JANG Byeong-Chun LEE 《The Journal of reproduction and development》2013,59(5):450-456
One of the factors that impairs in vitro produced porcine embryosis the oxidative stress that is mainly caused by the imbalance between reactiveoxygen species (ROS) generation and antioxidants activity, especially that ofglutathione (GSH). Here, we examined the effect of 7,8-dihydroxyflavone (7,8-DHF), akind of flavonoid antioxidant, on porcine oocyte maturation and its developmentalcompetence. Porcine oocytes were cultured in media supplemented with 0, 1, 5 and 10μM 7,8-DHF during both in vitro maturation (IVM) and invitro culture (IVC) after parthenogenetic activation. Maturation ofoocytes was evaluated based on first polar body (PB) extrusion and intracellular GSHlevel, and developmental competence was assessed through observing cleavage andblastocyst formation. In each step, the levels of intracellular GSH and ROS wereassessed by fluorescence intensity, and the apoptosis-related gene expression wasexamined using semiquantitative RT-PCR. The group treated with 1 μM 7,8-DHF duringIVM and IVC showed increased cytoplasmic maturation and reached the blastocysts stage(36.1%) at a higher rate than the other groups (24.7, 16.0 and 10.3% for 0, 5 and 10μM, P<0.05). In that group, the intracellular GSH level was significantlyincreased while ROS generation was significantly decreased after IVM and IVC(P<0.05). Moreover, it showed high expression of an anti-apoptotic gene(BCL2L1) and low expression of a pro-apoptotic gene(BAK1) (P<0.05). In conclusion, treatment with 1 μM 7,8-DHFduring IVM and IVC showed an anti-apoptotic effect by increasing intracellular GSHsynthesis and scavenging ROS and therefore improved the developmental competence ofporcine embryos. 相似文献
79.
Cho J Bhuiyan MM Shin S Park E Jang G Kang S Lee B Hwang W 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(12):1567-1573
The present study was conducted to establish an efficient production system for bovine transgenic somatic cell nuclear transfer (SCNT) embryos, the effect of various conditions of donor cells including cell type, size, and passage number on the developmental competence of transgenic SCNT embryos were examined with their expression rates of a marker gene. An expression plasmid for human prourokinase was constructed by inserting a bovine beta-casein promoter, a green fluorescent protein (GFP) marker gene, and a human prourokinase target gene into a pcDNA3 plasmid. Three types of bovine somatic cells including two adult cells (cumulus cells and ear fibroblasts) and fetal fibroblasts were prepared and transfected with the expression plasmid using a liposomal transfection reagent, Fugene6, as a carrier. In Experiment 1, three types of bovine cells were transfected at passages 2 to 4, and then trypsinized and GFP-expressing cells were randomly selected and used for SCNT. Developmental competence and rates of GFP expression in bovine transgenic SCNT embryos reconstructed with cumulus cells were significantly higher than those from fetal and ear fibroblasts. In all cell types used, GFP expression rates of SCNT embryos gradually decreased with the progression of embryo development. In Experiment 2, the effect of passage number of cumulus cells in early (2 to 4) and late (8 to 12) passages was investigated. No significant differences in the development of transgenic SCNT embryos were observed, but significantly higher GFP expression was shown in blastocysts reconstructed with cumulus cells at early passage. In Experiment 3, different sizes of GFP-expressing transfected cumulus cells [large (>30 microm) or small cell (<30 microm)] at passages 2 to 4 were used for SCNT. A significant improvement in embryo development and GFP expression was observed when small cumulus cells were used for SCNT. Taken together, these results demonstrate that (1) adult somatic cells as well as fetal cells could serve as donor cells in transgenic SCNT embryo production and cumulus cells with small size at early passage were the optimal cell type, and (2) transgenic SCNT embryos derived from adult somatic cells have embryonic development potential. 相似文献
80.
鱼类对常用水产药物的行为反应 总被引:3,自引:0,他引:3
以鲢鲫为实验材料,采用TL型鱼类回避槽,对28种常用水产药物作鱼类回避指数的测定;按测定结果分类(灭虫药、灭菌药、清塘药)列出鲢鲫对这些药物的敏感性顺序,可供鱼病防治中合理选用药物参考。作者还通过组织学方法观察鲫鱼的味蕾组织在药物渗透下的结构变化,证实鱼类的味蕾具有对外界化学物质的感受功能,与回避反应有关。 相似文献