全文获取类型
收费全文 | 232篇 |
免费 | 6篇 |
国内免费 | 6篇 |
专业分类
林业 | 9篇 |
农学 | 10篇 |
基础科学 | 6篇 |
17篇 | |
综合类 | 22篇 |
农作物 | 10篇 |
水产渔业 | 17篇 |
畜牧兽医 | 127篇 |
园艺 | 4篇 |
植物保护 | 22篇 |
出版年
2023年 | 4篇 |
2022年 | 8篇 |
2021年 | 20篇 |
2020年 | 7篇 |
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 23篇 |
2014年 | 21篇 |
2013年 | 16篇 |
2012年 | 11篇 |
2011年 | 10篇 |
2010年 | 14篇 |
2009年 | 13篇 |
2008年 | 17篇 |
2007年 | 7篇 |
2006年 | 14篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2003年 | 7篇 |
2002年 | 6篇 |
2001年 | 2篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1993年 | 3篇 |
1990年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1968年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有244条查询结果,搜索用时 0 毫秒
41.
BYEONG-TECK KANG KI-JIN KO DONG-PYO JANG JAE-YONG HAN CHAE-YOUNG LIM CHUL PARK JONG-HYUN YOO JU-WON KIM DONG-IN JUNG YOUNG-BO KIM EUNG-JE WOO ZANG-HEE CHO HEE-MYUNG PARK 《Veterinary radiology & ultrasound》2009,50(6):615-621
The purpose of this study was to describe relevant canine brain structures as seen on T2-weighted images following magnetic resonance (MR) imaging at 7 T and to compare the results with imaging at 1.5 T. Imaging was performed on five healthy laboratory beagle dogs using 1.5 and 7 T clinical scanners. At 1.5 T, spin echo images were acquired, while gradient echo images were acquired at 3 T. Image quality and conspicuity of anatomic structures were evaluated qualitatively by direct comparison of the images obtained from the two different magnetic fields. The signal-to-nose ratio (SNR) and contrast-to-noise ratio (CNR) were calculated and compared between 1.5 and 7 T. The T2-weighted images at 7 T provided good spatial and contrast resolution for the identification of clinically relevant brain anatomy; these images provided better delineation and conspicuity of the brain stem and cerebellar structures, which were difficult to unequivocally identify at 1.5 T. However, frontal and parietal lobe and the trigeminal nerve were difficult to identify at 7 T due to susceptibility artifact. The SNR and CNR of the images at 7 T were significantly increased up to 318% and 715% compared with the 1.5 T images. If some disadvantages of 7 T imaging, such as susceptibility artifacts, technical difficulties, and high cost, can be improved, 7 T clinical MR imaging could provide a good experimental and diagnostic tool for the evaluation of canine brain disorders. 相似文献
42.
AIM:To investigate the effects of Xijiao Dihuang and Yinqiao San decoction (XDY) on the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in mouse lung tissues and rat pulmonary microvascular endothelial cells (RPMVECs) infected with influenza virus, and to explore its mechanism for treatment of viral pneumonia. METHODS:Fifty-four male BALB/c mice were randomly divided into normal group, model group and XDY group (n=18 in each group). The viral pneumonia model was established by intranasally dripping influenza A (H1N1) virus into the mice. The mice in XDY group were treated with XDY 1 h after dripping the virus. The expression of ICAM-1 and VCAM-1 in lung tissues was examined by immunohistochemical staining 2, 4 and 6 d after infection. On the other hand, RPMVECs were obtained from male Wistar rats and primarily cultured. The cells were randomly divided into control group, virus group, virus+XDY group, tumor necrosis factor α (TNF-α) group and TNF-α+XDY group. The mRNA and protein expression of ICAM-1 and VCAM-1 was evaluated by real-time PCR and flow cytometry 24 h after infection. RESULTS:Virus exposure increased ICAM-1 and VCAM-1 expression in mouse lung tissues (P<0.01), and XDY treatment attenuated this effect (P<0.01). Virus and TNF-α both led to the increases in mRNA and protein expression of ICAM-1 and VCAM-1 in RPMVECs (P<0.01), which were also reduced by treatment with XDY (P<0.01). CONCLUSION:Treatment with XDY decreases virus-induced ICAM-1 and VCAM-1 expression, suggesting an important role of XDY in treatment of viral pneumonia. 相似文献
43.
Shuai ZHANG Xin WU Dandan HAN Yong HOU Jianzhuang TAN Sung Woo KIM Defa LI Yulong YIN Junjun WANG 《农业科学与工程前沿(英文版)》2021,8(1):15
44.
45.
The effect of dietary substitution of casein with fishmeal, soybean meal and crustacean meal on the growth of the abalone Haliotis discus hannai Ino was determined. A 350 g casein per kilogram diet was included into the CS diet. The whole casein was then substituted by: (1) 300 g fishmeal and 200 g soybean meal per kilogram diet (FS), (2) 200 g fishmeal, 200 g soybean meal and 130 g krill meal per kilogram diet (FSK), (3) 200 g fishmeal, 200 g soybean meal and 280 g red crab meal per kilogram diet (FSC) or (4) 200 g fishmeal, 200 g soybean meal and 130 g shrimp head meal per kilogram diet (FSS). In addition, a 50‐g by‐product of green tea per kilogram diet was included in the FS diet to form the FSG diet. Sea tangle (ST)diet was supplied to abalone as a control feed. Weight gain, final shell length and final shell width of abalone fed with the various substitution feeds (FS, FSK, FSC, FSS and FSG) were not different from those obtained with the CS diet. All the formulated feeds, however, produced higher weight gain and final shell width values than the ST diet. The results of this study show that casein can be replaced with a combination of fishmeal, soybean meal, krill meal, crab meal and/or shrimp head meal in the diet without a retardation of growth of abalone. 相似文献
46.
大豆蛋白-多糖复合物结构与性能及其稳定性研究 总被引:1,自引:0,他引:1
以大豆分离蛋白(SPI)、阿拉伯树胶(GA)及卡拉胶(CA)为原料,经物理混合成功制备不同多糖与SPI复合物,考察不同添加量(SPI与GA/CA质量比为20、15、10、5)对蛋白-多糖复合物结构、性能变化趋势及其乳液稳定性的影响规律,最终探明蛋白与不同多糖复合物的相互作用机制;运用红外光谱、荧光光谱及电子显微镜解析不同复合物的结构特征,采用乳化特性、粒径、Zeta-电位、表面疏水性等指标明确不同复合物的理化特性,并通过探讨不同复合物乳液的乳化活性、乳化稳定性、表观粘度及乳析指数明晰其稳定特性。结果表明,两种多糖在酸性条件下可与SPI生成复合物,并且当SPI与CA质量比为20时,复合物的Zeta-电位最高,为(20.47±0.82) mV,平均粒径最小,为(1.37±0.01)μm,分布均匀,乳化活性指数最高,为(106.46±4.75) m2/g,乳化稳定性指数为(145.33±8.53) min,此时复合乳液的稳定性较好,CA的加入显著降低SPI内源荧光强度并改变SPI的二级结构,SPI与CA结合形成了稳定的复合物。 相似文献
47.
48.
K. LEANN KUEBELBECK DVM DONNIE E. SLONE DVM MS Diplomate ACVS KIM A. MAY DVM 《Veterinary surgery : VS》1998,27(2):132-137
Objective —To determine if omentectomy would decrease the frequency of postoperative intraabdominal adhesions. Study Design —Retrospective study. Animals or Sample Population—44 horses that had either two ventral median celiotomies or a ventral median celiotomy and a necropsy more than 4 days later; 19 of these horses had their omentum removed at the initial surgery. Methods —Data retrieved from the records included location and type of intraabdominal adhesions; location of the surgical lesion; relationship of adhesions to the surgical lesion; surgical procedures; duration of initial surgery; time interval between procedures; age, gender, and breed of the horse; and clinical outcome. Fisher's exact test was used to evaluate the association between categorical explanatory and outcome variables. The effect of potential risk factors on the incidence rate of adhesion formation was estimated using a proportional hazards regression model. Results —Of 25 horses in the nonomentectomy group, 15 (60%) had postoperative adhesions that resulted in the need for a second surgical intervention, whereas of 19 horses that had omentectomy initially, only 4 (21%) had postoperative adhesions that required a second procedure. Rate of adhesion formation was higher in horses that did not have omentectomy initially (incidence ratio rate [IRR], 0.46; 90% confidence interval [CI], 0.18 to 1.19). At initial surgery, 24 horses had a small intestinal lesion, and 20 horses had a large intestinal lesion. Fifteen horses (63%) with small intestinal lesions subsequently developed adhesions compared with four horses (20%) with an initial large intestinal lesion (P= .006). At the second procedure, small intestine lesions were identified in 32 horses and large intestine lesions in 12 horses (1 horse had both small and large intestine lesions), and 1 horse had a gastric lesion. Adhesions were identified as the cause of colic signs in 19 (61%) horses with small intestinal lesions and in none of the horses with large intestine lesions. The frequency of adhesion development leading to colic associated with only the small intestine at the second surgery or necropsy was significantly greater (P= .001) than the frequency only in the large intestine. Conclusions —Omentectomy reduced the rate of postoperative adhesion formation. Adhesions are more likely to occur after small intestinal surgery and if they do occur likely involve the small intestine. Clinical Relevance —Omentectomy is a safe procedure and should be considered prophylactically for reduction of adhesion formation after abdominal surgery in horses. 相似文献
49.
中韩古典园林是传统文化的结晶,并且是东方园林的两枝奇葩。中国园林与韩国园林属于本源和分支的关系,韩国园林很多方面传承了中国园林的造园手法及艺术特征;然而不同的自然人文环境也使两种园林风格迥异,在园林中起着十分重要构景作用的置石也不例外。本文试从置石的形态与应用手法对中韩园林的不同作一些分析。 相似文献
50.
Hyeryoung JEONG Hanbin LEE Jaihyun JUNG Hyunryung KIM Jin YU Hyounglok YOON Youngjae LEE Jinhwa CHANG Dongwoo CHANG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):581
Unlike echocardiography, cardiac magnetic resonance imaging (cardiac MRI) results in a near-exact assessment of cardiac structures and function. However, most veterinary studies have focused on dogs with normal cardiac function. We hypothesized that there would be significant differences in cardiac measurements between cardiac MRI and echocardiography when left ventricular (LV) function was abnormal. This study was undertaken to compare measurements of LV function produced by cardiac MRI and echocardiography in dogs whose LV function was altered by pharmacological agents. This study was conducted with six healthy beagle dogs. We increased left ventricular contractility by administration of dobutamine; we decreased cardiac contractility with esmolol. Stroke volume measurements were made by using both cardiac MRI and echocardiography under seven different conditions with general anesthesia: control, three doses of esmolol (100, 200, and 500 µg/kg/min), and three doses of dobutamine (10, 20, and 50 µg/kg/min). Experiments involving each condition were conducted at least 1 week apart. When LV contractility was normal, ejection fraction (EF) and stroke volume (SV), as measured by echocardiography and cardiac MRI, were not significantly different. However, when contractility was changed by pharmacological agents, EF and SV were overestimated by echocardiography, compared to MRI. Evaluation of cardiac function in patients treated with pharmacological agents should be conducted carefully because EF and SV measured by echocardiography can be overestimated, compared with EF and SV obtained by cardiac MRI. 相似文献