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1.
The assay was aimed to explore the effects of Ca2+ or K+ on dog cardiac function, and the role of Ca2+ and/or K+ on treating canine electrolyte disorders. 20 Chinese rural dogs at the age of 24 to 48 months were divided into two groups by age, gender and weight. Hyperkalemia (group Ⅰ) model was created by intravenous injection with 5% KCl at flow velocity of 1.5 mL/min, and then relieved the symptoms of hyperkalemia by intravenous injection with CaCl2 at flow velocity of 1 mL/min; hypercalcemia (group Ⅱ) model was created by intravenous injection with 5% CaCl2 at flow velocity of 1 mL/min, and then relieved the symptoms of hypercalcemia by intravenous injection with KCl at flow velocity of 1.5 mL/min.The blood was collected before and after the models built, and at the time of CaCl2 (KCl) was injected to the models.The sera were separated and used to detect the concentrations of K+, Ca2+, Na+, Cl-. Simultaneously, blood pressure, heart rates and electrocardiogram (ECG) were monitored at the same collecting points. The results showed that hyperkalemia model was established by intravenous injection with 5% KCl to the dog at flow velocity of 1.5 mL/min.At this time the serum concentration of K+ was significantly increased (P<0.05),heart rate extremely significantly decreased (P<0.01),SBP significantly decreased (P<0.05). The ECG showed that the model dogs were arrhythmia, P wave became flat or even disappeared, T wave was tall as mantle.While CaCl2 was injected to the hyperkalemia model by intravenous injection, the concentration of K+ was significantly decreased (P<0.05),the heart rate significantly increased (P<0.05), The ECG showed that P wave reappeared,mantle-like T wave disappeared.Hypercalcemia model was established by intravenous injection with 5% CaCl2 to the dog at flow velocity of 1 mL/min.At this time the serum concentration of Ca2+ was extremely significantly increased (P<0.01), the concentration of Na+ decreased (P<0.05),the heart rate significantly increased (P<0.05),pulse pressure extremely significantly decreased(P<0.01). The ECG showed that T wave was widened,ST segment was shortened or even disappeared,QT interval was shortened,U wave was appeared.While KCl was injected to the model dogs by intravenous injection, the serum concentration of Ca2+ decreased (P>0.05), the heart rate significantly decreased (P<0.05) and returned to normal, but pulse pressure continued to decline.The ECG showed that T wave was apparently elevated.The time limit of ST segment increased.U wave was disappeared. The conclusions were that hyperkalemia (hypercalcemia) model could established after 5% KCl (5% CaCl2) injected to the healthy dogs. The heart fuction recovered obviously when CaCl2 was injected to the hyperkalemia dogs, therefore, CaCl2 had a better therapeutic effect for hyperkalemia. However, it had no good therapeutic effect when KCl injected to the hypercalcemia dogs.  相似文献   
2.
鸡源致病性奇异变形杆菌的分离鉴定与遗传进化分析   总被引:2,自引:2,他引:0  
徐睿  李颜桃 《中国畜牧兽医》2018,45(9):2550-2558
为了解鸡源奇异变形杆菌的耐药情况、致病力和遗传特征,本试验从凉山地区分离得到2株细菌(YLF1、WS),通过培养特征、镜检特征和16S rRNA序列测定对分离菌进行鉴定及致病性试验;采用(K-B)法检测分离菌对14种常用抗生素(包括β-内酰胺类、头孢烯类、氨基糖苷类、四环素类、氟喹诺酮类、大环内酯类)的敏感性;并与GenBank中公布的21种不同来源的变形杆菌16S rRNA基因序列进行遗传进化分析。结果表明,YLF1、WS菌株均具有迁徙性和β-溶血生长特征,镜检为革兰氏阴性长短不一的杆菌或球菌,经16S rRNA基因鉴定与GenBank中奇异变形杆菌同源性均在99%以上,YLF1、WS菌株确定为奇异变形杆菌,均表现为多重耐药,耐药率分别为78.6%(11/14)和71.4%(10/14);雏鸡致死率均为80%;YLF1、WS菌株与日本人体分离株、中国新疆黄牛分离株和中国广东土壤分离株同源性最高,达99.9%;与来自中国河南、中国新疆及印度的鸡源奇异变形杆菌同源性较高(98.9%~99.3%),遗传关系密切。表明凉山地区鸡群中存在奇异变形杆菌感染,分离株有较高的致病力和较强的耐药性,也提示分离菌可能来源于环境、感染鸡或其他动物,同时存在人畜共患的潜在危险。  相似文献   
3.
利用A-PAGE(Acid-polyacrylamide gel electrophoresis)对来源于7个国家的76份栽培荞麦(苦荞54份,甜荞22份)醇溶蛋白遗传多样性进行评价。结果表明,荞麦醇溶蛋白位点存在丰富的等位变异,共分离出18条迁移率不同的谱带,每份材料具有6~12条不等,平均9.5条,多态性带占88.89%。材料间平均遗传相似系数(GS)为0.777,变幅为0.389~1.000。在GS为0.63的水平上供试材料可聚为苦荞和甜荞两大类,绝大部分来自于相同或相似生态地理环境的材料聚成一类,表明荞麦醇溶蛋白所揭示的遗传关系与地理来源有较高的相关性。  相似文献   
4.
本文叙述了2010年中国农业科学院农业生物资源考察队对四川及藏东南荞麦资源的详细调查结果.考察队共调查了40个乡镇的120个村,360余个村小组,共获得荞麦资源88份,其中苦荞资源64份,甜荞资源20份,野生荞麦资源4份.当地少数民族认知有价值的荞麦资源分别是长锥大粒型资源、短锥皮薄型资源、抗病资源、抗虫资源、抗旱资源和抗寒资源等.  相似文献   
5.
江文世  陈雯雯 《湖北农业科学》2011,50(12):2526-2528
研究三角梅色素的提取工艺,结果表明,以去离子水及葡萄糖为浸提液的最大吸收波长均为540nm,采用0.03 g/mL的葡萄糖溶液作为浸提液浸提效果好,对应的浸提时间是9~10h,pH值为6~8为宜.  相似文献   
6.
曹向杰 《湖北农业科学》2011,(17):3640-3642
四川省凉山州拥有丰富的可再生能源,资源富饶与农村贫困并存.可再生能源开发利用项目对缓解农村能源贫困、促进农民脱贫致富有着现实的意义.凉山州在开发利用可再生能源过程中,应该包容和承担扶贫任务.在一些地方的某些项目,甚至应该围绕扶贫工作来展开.  相似文献   
7.
To study the genetic variations of Ascaridia galli (A. galli) and the phylogentic relationships with other Ascaridata, fragment of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene and complete sequence of NADH dehydrogenase subunit 4 (nad4) gene of 15 adult A. galli isolated from Xichang city in Sichuan province were amplified by PCR, then analyzed the sequences. NJ trees and Bayes trees based on pcox1 and pnad4 genes were reconstructed. The partial sequences of cox1 gene and complete sequence of nad4 gene were 1 152 and 1 236 bp, respectively. There were 33 and 40 variable sites in the pcox1 and nad4 gene sequences, the intraspecific sequence variations within A. galli were 0 to 2.1% for pcox1 gene, 0 to 2.3% for nad4 gene. 8 and 11 haplotypes were detected in pcox1 and nad4 genes, the global haplotype diversity were 0.733±0.124 and 0.933±0.054, the nucleotide diversities were 0.00433±0.00153 and 0.00541±0.00157, and the average genetic distances were 0.004 and 0.005, respectively. Phylogenetic trees based on pcox1 and pnad4 genes with Neighbour-Joining and Bayesian analysis method revealed that all A. galli were clustered in one clade, and they were more closely related to A. columbae than any other members of Ascaridata. These findings indicated that 15 isolates of A. galli from Xichang city kept low genetic variation, nad4 gene was more suitable and effective than cox1 gene as molecular marker for detecting genetic variation of A. galli.  相似文献   
8.
大豆与烤烟不同套作年限对根际土壤微生物数量的影响   总被引:5,自引:0,他引:5  
为克服烟田连作障碍、提高烤烟产量和质量,以大豆套作烤烟为种植模式,调查大豆与烤烟不同套作年限下根际土壤三大类群微生物和与氮代谢相关的功能性微生物群落的数量变化及其与烤烟主要土传病害的发生情况之间的相互关系。结果表明,烤烟-大豆带状套作显著增加作物根际土壤的细菌(B)、放线菌(A)数量、B/F和A/F值,减少真菌(F)数量;也提高与土壤氮素代谢相关的氨化细菌、硝酸细菌、亚硝酸细菌、自生固氮菌等功能性微生物数量;烟豆套作能降低烤烟主要土传病害的发生,其发生程度与烤烟根际土壤细菌及放线菌数量显著负相关,而与真菌数量极显著正相关。随着套作年限的延长,根际土壤的细菌(B)、放线菌(A)、B/F和A/F值以及氨化细菌、硝酸细菌、亚硝酸细菌、自生固氮菌等有益菌群数量大幅度增加,真菌(F)及反硝化细菌的数量显著减少,对烟草土传病害的相对防治效果明显提高,以上效应表现为烤烟-大豆带状套作3年(A3)烤烟-大豆带状套作2年(A2)烤烟-大豆带状套作1年(A1)。  相似文献   
9.
以苦养麸皮为原料,用白酒浸泡,探究苦荞麸皮中黄酮溶入白酒的最佳条件和感官评价。通过不同固液比、酒度和时间进行单因素试验,确定各单因素在苦荞麸皮泡酒中黄酮溶入的较适宜范围,再通过正交试验确定出黄酮溶入的最佳条件,并对各产品进行感官评价。结果表明,影响黄酮溶入的主次关系为酒度>时间>固液比;当酒度为60%,时间为5 h,固液比为1:25时,白酒中溶入黄酮含量最高为3%;其产品感官评价均良好。  相似文献   
10.
为了解和掌握邛海湿地观赏昆虫资源现状,2010年6月至2011年9月对邛海湿地观赏昆虫进行了调查和采集,共采得观赏昆虫9目44科91种,以鞘翅目、鳞翅目、直翅目等3目为优势目,斑腿蝗科、蜻科、蛱蝶科等7科为优势科,中华稻蝗(Oxya chinensis)、红蜻(Crocothemis servilia servil)、菜粉蝶(Picris rapae)等13种为优势种。就观赏价值来看,该区域观赏昆虫以形态类观赏昆虫为主。从功能群来看,该区域观赏昆虫以植食类昆虫为主。结合调查结果与文献资料,提出了关于邛海湿地观赏昆虫资源市场开发建议。  相似文献   
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