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51.
A 6-month-old stunted female Doberman Pinscher was found to have a 77,X0 chromosomal complement. The ovaries were small, consisting primarily of interstitial-type cells and solid epithelial cords. The dam, sire, and a male littermate had normal karyotypes.  相似文献   
52.
A standardized investigation was conducted to compare the biophysical properties of hyaluronate products used in the treatment of joint dysfunction in horses. Results showed that two of the five products, Hyvisc® and Hylartin®V, contained higher-weight molecular hyaluronate (greater than 1.5×106). Other investigations have shown that higher molecular weight hyaluronate is effective in providing physical resistance to shear, in stimulating endogenous hyaluronate synthesis, and in inhibiting excess cell proliferation which may be associated with synovial pannus formation. It is suggested that the therapeutic benefits of hyaluronate products may be dependent on the molecular size of the hyaluronate molecules. Higher molecular weight hyaluronate products would be expected to be more effective than lower molecular hyaluronate products in providing therapeutic benefits.  相似文献   
53.
The objective of the study was to determine the relationship between morphological findings of the surface of teat duct particularly the level of ceratosis and the prevalence of intramammary infections (IMI). The study was conducted on a commercial dairy herd housing about 3000 lactating dairy cows. We examined 891 quarters in the middle of lactation. Duplicate samples of quarter foremilk were collected monthly. The bacteriological status of quarters was determined according to the recommendations of IDF. At the same time teats were evaluated by clinical examinations. The appearance of teat skin lesions and the status of the teat duct especially the existence of hyperceratosis (HC) was documented. Four classes of teat duct hyperceratosis were defined: without, slight, medium and severe HC. The rate of IMI in different classes of hyperceratosis of teat duct was compared by Chi-square analysis. Prevalences of intramammary infections were determined three times (P1, P2 and P3) during the study period. Prevalence of infection was high for S. aureus (P1: 5.6% vs. P2: 4.5% vs. P3: 4.3%), Sc. agalactiae (P1: 2.7% vs. P2: 2.6% vs. P3: 2.8%) and CNS (P1: 10.7% vs. P2: 8.8% vs. P3: 9.6%). Furthermore we detected IMI caused by other streptococci, yeast, E. coli and mixed infections. A positive correlation between status of HC and prevalence of IMI for Sc. agalactiae was found. At the second and third sampling time the rate of intramammary infection with Sc. agalactiae in quarters with medium HC (P2: 9.21% and P3: 13.73%) differed significantly (p < 0.05) compared to groups without (P2: 1.56% and P3: 1.91%) and slight hyperceratosis (P2: 2.33% and P3: 2.56%). The results of our study indicate a correlation between morphology of teat duct surface, especially regarding to Sc. agalactiae. On one hand HC can cause high intramammary infection rate with Sc. agalactiae. On the other hand it is possible that HC is the consequence of a quarter infection with Sc. agalactiae. Further research is required.  相似文献   
54.
The objective of this study was to compare the clinical and laboratory consequences of left and right displacement of the abomasum (LDA and RDA), short- and long-term survival after surgery and the findings in cows, that could not be cured by omentopexy. Data from 564 cases of displaced abomasum (466 LDA, 98 RDA) were analysed retrospectively. Clinical and laboratory findings were compared between the two manifestations of DA. Survival was assessed after 10 days and after 15 months. Necropsy was carried out on cows that died or were killed. On arrival at the clinic, left displacement of the abomasum (LDA) cows had been recognized as diseased for longer. LDA occurred earlier in lactation, and more cows with right displacement of the abomasum (RDA) were pregnant. Overall clinical symptoms were more severe in RDA than in LDA cows. Heart rate was higher, body temperature was lower, inanition, abnormal faeces and ruminal stasis were more frequent in RDA cows. Leucocyte counts were higher, and potassium and chloride levels were lower in RDA cows. Acetonuria was more frequent in LDA cows. More LDA than RDA cows were released from the clinic as cured (82.0% versus 74.5%). However, survival after the early post-surgical period was similar for RDA and LDA cows. At necropsy, diseases of the gastrointestinal system were the predominant finding in RDA cows, while in LDA cows, diseases of the liver and other concurrent diseases were more important.  相似文献   
55.
Fasciola gigantica and Stilesia hepatica constrain ruminant productivity. The prevalence and economic losses caused by F. gigantica and S. hepatica in the ruminant production systems of Taveta division of Kenya were estimated in a retrospective appraisal of the slaughter records on the total number of animals slaughtered and livers condemned over the period 1989 to 2004. Only liver condemnations based on infestation by F. gigantica and S. hepatica were considered for purposes of this study. Liver condemnation rates differed significantly between bovines, caprines and ovines (p≤ 0.05) for F. gigantica (26%, 6.6% and 5.2%, respectively) and for S. hepatica (0.4%, 22% and 28%, respectively). The total loss through condemnation of both F. gigantica and S. hepatica infested livers was 4 408 272 KES (Kenyan shillings) (US$ 72 272). The proportion of loss in bovines, caprines and ovines, was 76%, 17% and 7%, respectively. Fasciolosis contributed 3 505 410 KES (79.5%) and S. hepatica infestation 903 210 KES (20.5%) to the total losses due to liver condemnations. The authors feel strongly that there is a need for more work on the two parasites using live animals to determine the prevalence in animals of various ages, species and breeds and the economics of disease control at farm level.  相似文献   
56.
【目的】建立羊踯躅嫩叶离体培养及植株高效再生体系。【方法】以羊踯躅新生嫩叶为外植体,筛选嫩叶愈伤组织诱导、再分化及生根培养基,并以再生植株茎节为试材,建立高效植株再生体系。【结果】最适合羊踯躅嫩叶愈伤组织诱导的培养基为1/2 DR+2.40 mg/L 2ip+0.80 mg/L NAA,诱导率为99.5%;愈伤组织再分化的最佳培养基为1/2 DR+2.90 mg/L 2ip+0.01 mg/L NAA+1.75 mg/L KT,分化率为99.7%;适宜生根的培养基为1/4 DR+0.06 mg/L ZT+0.02 mg/L NAA,生根率达99.0%。利用再生植株茎节的快繁结果表明,在28 d的培养周期内,每节段平均增殖达5倍以上。【结论】成功建立了羊踯躅嫩叶愈伤组织诱导、再分化芽苗和植株高效再生体系,可以满足羊踯躅工厂化育苗的需要。  相似文献   
57.
杨茹薇  巴合旦  秦勇  申耀荣 《种子》2012,31(6):100-102
用一定浓度的赤霉素(GA3)、生长素(IAA)、过氧化氢(H2O2)、硝酸钾(KNO3)、萘乙酸(NAA)溶液处理可显著提高辣椒砧木品种肩车种子的发芽率,并对其发芽势、发芽指数有一定的促进作用。比较几种药剂对辣椒种子发芽的影响发现,GA3和IAA对辣椒种子的发芽影响效果最佳,最适宜浓度分别为200 mg/L和1.5 mg/L。  相似文献   
58.
铜、镉污染对小麦种子萌发及幼苗生长的影响   总被引:1,自引:0,他引:1  
吕笃康  巴音山  赵玉 《种子》2012,31(9):108-111
以小麦种子为试材,通过水培试验研究了铜、镉污染对小麦种子萌发及幼苗生长的影响。结果表明,在实验所选的胁迫浓度范围内,单一铜污染时,对小麦种子萌发初期有短暂的促进作用,小麦种子发芽率随着Cu2+浓度的升高,呈先升后降。在20 mg/L Cu2+处理时出现了毒性兴奋效应现象。铜、镉污染对小麦幼苗的苗长和根长的抑制作用较为显著。根据综合效应指标,铜、镉复合污染对小麦种子萌发的影响表现形式为铜、镉的协同作用。  相似文献   
59.
冬枣树皮疱斑病Phoma persicae是近年在冬枣上新发生的一种重要病害,2009~2011年对其开展了室内抑菌测定和田间防效试验。结果表明,室内抑菌效果较好的药剂为苯醚甲环唑、丙环唑、氟硅唑、苯醚甲环唑.丙环唑、恶唑菌酮.氟硅唑,抑菌率分别为98.7%、96.2%、94.9%、93.6%、92.3%;田间防治效果较好的药剂有苯醚甲环唑、嘧菌酯、氟硅唑、中生菌素,防治效果分别为90.2%、87.1%、80.4%、69.1%,可以在防治冬枣树皮疱斑病生产中推广使用。  相似文献   
60.
采用荷斯坦奶牛X性控冻精和超数排卵技术结合生产奶牛性控胚胎,以建立高效、低成本的体内性控胚胎生产方法。研究发现,使用CIDR和Cue-Mate进行奶牛同期发情处理,发情率分别为90.9%和100%(P<0.05),且Cue-Mate的发情时间更加集中;加拿大的FOLLTROPIN-V和中国科学院动物研究所的FSH对奶牛超排效果影响不显著,分别为头均胚胎数10.08枚±8.08枚、头均可用胚胎数2.38枚±3.07枚和头均胚胎数6.57枚±4.31枚、头均可用胚胎数2.00枚±1.88枚,无显著差异(P>0.05);奶牛发情后12h~14h和16h~19h人工授精,分别获得头均胚胎数10.25枚±5.53枚、头均可用胚胎数5.33枚±4.52枚和头均胚胎数10.13枚±6.93枚、头均可用胚胎数5.88枚±6.26枚,无显著差异(P>0.05)。但是未受精胚胎数差异显著(27对7,P<0.05)。  相似文献   
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