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31.
The study of the development of the mesonephros in the camel (Camelus dromedarius) was carried out on 16 embryos ranging from 0.9 to 8.6 cm crown vertebral rump length (CVRL). At 0.9 cm CVRL, the mesonephros is represented by a narrow strip along the roof of the thoracolumbar part of the vertebral column. At 1.4 cm CVRL, some of the mesonephric tubules are canalized but others are still solid. The mesonephric corpuscles are well developed at 1.9 cm CVRL and occupy almost the entire abdominal cavity in between the liver and the gut. Histologically, the glomeruli occupy the ventromedial aspect of the mesonephros while the mesonephric tubules become numerous, larger and more coiled. At 3 cm CVRL, the metanephros is invaginated in the caudal pole of the mesonephros, and the mesonephric tubules in some areas are differentiated into secretory and collecting tubules. At 3.5 cm CVRL the mesonephros is related dorsally to the postcardinal vein and ventrally to the subcardinal vein. At 4.7 cm CVRL continuous regression of the mesonephros from cranialwards to caudalwards is observed. At 5.3-5.5 cm CVRL, the cranial part of the mesonephros is divided into medial and lateral regions, and later the medial region completely disappears and is replaced by the primordium of the adrenal gland. At 8.6 cm CVRL, the caudal part of the mesonephros completely disappears.  相似文献   
32.
Development of multifunctional textile and clothing products with improved environmental profiles has been demanded both by textile industry and by consumer. Herein, dialdehyde sodium alginate (DASA) and dialdehyde carboxymethyl cellulose (DACMC) have been prepared, characterized and utilized, as an eco-friendly binding/ macromolecular crosslinking/hand building agents, in functional finishing of cellulose-containing fabrics. Fabric samples were treated with the nominated dialdehyde polysaccharide (DAPS, 10 g/l) along with the reactant resin (DMDHEU, 50 g/l), Ag- or TiO2-NPs as active ingredients (20 g/l) and ammonium persulfate catalyst (5 g/l) using the padding method. After functional finishing, the finished fabrics demonstrated a remarkable improvement in their antibacterial efficacy, UV-blocking ability, self-cleaning capacity, and surface roughness functionality without adversely affecting fabrics resiliency. The variation in these functional properties is affected by kind of DAPS, type of added nanoparticles as well as the treated substrate. Additionally, FTIR, SEM, EDS, and durability to wash measurements for selected samples were performed. Moreover, pre-oxidation of DAPS, functionalization reactions/interactions among the nominated reactants and the textile materials were also suggested.  相似文献   
33.
家禽病毒性肿瘤病是最常见的自发性肿瘤病,包括疱疹病毒病、马立克氏病、反转录病毒病、白血病、网状内皮组织增生症和淋巴细胞增生症.商业鸡群中不明病因的肿瘤病发生几率很低,这是因为商业鸡群的生活时间通常都很短(少于肿瘤发生所需的时间).但是,多中心组织细胞增生症和扁平真皮癌(家禽角化棘皮瘤)是商业肉鸡经常发生的2种不明病因的肿瘤病[1~3].  相似文献   
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<正>病毒性肿瘤病是家禽最为常见的自发性疾病,可致肿瘤性死亡和生产性能下降,造成重大经济损失。这类疾病包括由反转录病毒引起的禽白血病、禽网状内皮组织增生症、火鸡淋巴细  相似文献   
36.
Diagnostic strategies to detect contagious mastitis caused by Mycoplasma bovis, Staphylococcus aureus, and Streptococcus agalactiae in dairy herds during an outbreak have been minimally studied with regard to cost and diagnostic sensitivity. The objective of this cross-sectional study was to compare the cost-effectiveness of diagnostic strategies for identification of infected cows in two California dairy herds during contagious mastitis outbreaks.  相似文献   
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The purpose of this study was to examine the effect of some immunostimulants and probiotics on the survival rate, final weight, and disease resistance of overwintered tilapia fry. There were five treatments: T1 (control) fed a balanced diet (35% protein) without additives. Treatments 2 to 5 were fed diets supplemented with 4% garlic, 4 g/kg Echinacea, 4 g/kg Organic Green or 4 g/kg Vet-Yeast, respectively. Growth and resistance to disease challenge with Aeromonas hydrophila and Pseudomonas flourescens were not different among treatments, but survival of overwintered fry increased in treatments fed probiotics or immunostimulents. The use of garlic in overwintering feeds could allow hatchery operators to increase their prices for fry and fish farmers to stock production ponds earlier, increasing hatchery revenues by 74% and improving land use efficiency and productivity for the Egyptian aquaculture industry.  相似文献   
39.
An outdoor pot experiment was conducted in 2014/2015 growing season at Giza Agricultural Research Station to evaluate powdery mildew (PM) severity on 18 flax lines. The tested lines were divided into two distinct groups. The first group included 12 highly resistant lines (HRLs). Disease severity on these lines ranged from 1 to 10%. The second group included 6 highly susceptible lines (HSLs) where disease severity ranged from 90–100%. Levels and activities of phenols, alkaloids, proteins, proline, polyphenol oxidase and peroxidase significantly increased in the infected leaves of the HRLs, compared with the HSLs. Of these components, phenols and peroxidase showed the highest increases in the HRLs (102.34 and 199.33%, respectively). These results indicate that the tested biochemical components have roles to play in flax defense against PM through a variety of mechanisms. The results also suggest that phenols or peroxidase in infected leaves could be used in breeding programs to select resistant lines at early stage of PM development.  相似文献   
40.
A greenhouse experiment was conducted to investigate the impact of water and salt stress in Quinoa plants (Chenopodium quinoa Willd.). Irrigation treatments using saline solutions of 0 (control), 50(T1), 200(T2), 400(T3), 600(T4), and 800(T5) mM sodium chloride (NaCl) were adopted. The results indicated that quinoa plants can tolerate water stress (50%FC) when irrigated with moderately saline water (T1 and T2, respectively). Salinity stress increases quinoa drought tolerance in terms of biomass production. Neither osmotic stress nor ions deficiency/toxicity seems to be determinant under T1 and 100%FC. Salinity induced a significant increase of sodium (Na+) and chloride (Cl?), while reduced magnesium (Mg2+) and calcium (Ca2+) in stems, leaves, seed’s coating, and seeds. The potassium (K+)/Na+ ratio never fell below 1 with T1; yet, fell to 0.78 and 0.89 with T2 for 100% and 50%FC, respectively. The seed coat limited the passage of possibly toxic concentrations of Na+ and Cl? to seed interior, as high Na+ and Cl? was found in the seed coat.  相似文献   
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