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131.
132.
Fifteen close up pregnant Murrah buffaloes of mean body weight (668.3 ± 24.03) kg, lactation number (2.8 ± 0.17) and expected producing ability (EPA) (2125.7 ± 46.34) were randomly distributed into three groups each of five animals to investigate the performance at different levels of metabolizable energy and protein. Control group was fed as per ICAR Nutrient requirements of animals (2013) recommendation whereas treatment group (1) high metabolizable energy and high metabolizable protein (HMEMP) and group (2) low metabolizable energy and low metabolizable protein (LMEMP) were offered with ration containing 15% more and 15% less ME and MP, respectively. The feeding trial was carried out for the period of 40 days before parturition and continued for 120 days after parturition. Intake of dry matter (DM) (%BW) was similar among experimental groups. Metabolizable energy (ME) (MJ/100 kg BW) and metabolizable protein (MP) (g/100 kg BW) intake was highest in HMEMP followed by control and LMEMP group, respectively. Digestibility trial of 7 days was conducted at 60 days post-partum and it was observed that apparent digestibility coefficients (%) of DM, organic matter (OM), crude protein (CP), ether extracts (EE), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were similar among the experimental groups. Milk yield (kg/kg DMI) was similar among treatment groups whereas 6% fat corrected milk (FCM) was lower in LMEMP group as compared to HMEMP and control. No significant effect of dietary MP and ME levels on milk composition was observed among experimental groups. There were no significant difference in non esterified fatty acid (NEFA), blood urea nitrogen(BUN), growth hormone (GH) and insulin like growth factor-1(IGF-1) concentration among different experimental groups whereas concentration of immunoglobulin G (IgG) (μg/ml) was found to be lower in LMEMP. The study results indicate that nutrient digestibility and lactation performance was not affected with 15% variation in intakes of ME and MP in lactating Murrah buffaloes.  相似文献   
133.
A study was conducted to determine the effects of stage of maturity on ensiling characteristics and ruminal nutrient degradability of oat silage. Oat was field grown and forage was harvested at the boot or soft dough stage and ensiled in mini-silos for 0, 2, 4, 8, 16 and 45 days. Two lactating Holstein cows fitted with ruminal fistulas were used determine ruminal nutrient degradability. Regardless of the stage of maturity, ensiled forages went through a rapid fermentation with a sharp decline in pH during the first 2 days of ensiling. Extensive proteolysis took place between 0 and 2 days as indicated by a reduction in true protein and neutral detergent insoluble protein (NDICP) and an increase in non-protein nitrogen (NPN). Chemical analysis of the 45 days silage showed that stage of maturity had no effect on neutral detergent fibre (NDF) and acid detergent fibre (ADF) of oat silage. However, oat harvested at the boot stage contained more crude protein (CP) and less starch than that harvested at the soft dough stage. Distribution of protein fractions showed that oat harvested at the boot stage contained lower NPN, NDICP and acid detergent insoluble protein than oat harvested at the soft dough stage. Results of the in situ incubation experiment indicated that oat harvested at the soft dough stage had lower ruminal dry matter (60.6 vs. 66.4%). CP (81.3 vs. 88.7%) and NDF (35.4 vs. 42.2%) degradabilities than oat harvested at the boot stage. It was concluded that chemical composition and ruminal nutrient degradability of oat silage are significantly influenced by stage of maturity.  相似文献   
134.
Grazing at high stocking rates may increase sediment and nutrient loading of pasture streams through transport in precipitation runoff and bank erosion. A 3-yr (2007–2009) grazing study was conducted on 13 cool-season grass pastures to quantify effects of stocking rate and botanical composition on forage sward height, proportions of bare and manure-covered ground, and bank erosion adjacent to streams. Pastures ranged from 2 ha to 107 ha with stream reaches of 306 m to 1 778 m that drained watersheds of 253 ha to 5 660 ha. Bare and manure-covered ground were measured at a 15.2-m distance perpendicular to the stream at 30.5-m intervals at up to 30 locations on each side of the stream by the line transect method in May, July, September, and November of each year. At the midpoint of the 15.2-m line, forage sward height was measured with a falling plate meter (4.8 kg · m-2) and plant species identified. In November 2006, fiberglass pins (1.6 × 76.2 cm) were driven 73.7 cm into the stream bank at 1-m intervals from the streambed to the top of the bank along 10 equidistant transect locations on each side of the stream to measure bank erosion during spring, summer, and fall of each year. Increasing pasture stocking rates increased manure-covered ground and decreased sward height, but did not affect proportions of bare ground. The greatest, intermediate, and least net soil erosion rates occurred during the winter/early spring, late spring/early summer, and late summer/fall seasons. Stocking rates between measurements, expressed as cow-days · m-1 stream, were not related to bank erosion. Increasing stocking rates per unit of stream length will increase manure cover and decrease forage sward height, but not affect proportions of bare ground or bank erosion rates adjacent to pasture streams. Therefore, managing stocking rates may reduce nutrient loading of pasture streams.  相似文献   
135.
This study investigated the protective effects of 1 mM Vitamin C and 1 mM Trolox on kinematic and oxidative stresses in rainbow trout (Oncorhynchus mykiss) sperm cells against flower‐like zinc oxide nanoparticles (ZnO‐NP, 1 mg/L) in vitro, during 2 hr. Trolox showed protective effects on all kinematic parameters measured for sperm cells against ZnO‐NPs, whereas Vitamin C only affected angular path velocity (VAP), linearity (LIN) and amplitude of lateral displacement of the sperm cell head (ALH). Although ZnO‐NPs reduced total glutathione (TGSH) and catalase (CAT) compared with the control, there were positive treatment effects for both Trolox and Vitamin C on antioxidant capacity. Conversely, while ZnO‐NP increased the rate of malondialdehyde (MDA) lipid peroxidation, it decreased following antioxidant therapy. This research suggests that Trolox and Vitamin C play a protective role for rainbow trout sperm exposed to ZnO‐NP.  相似文献   
136.
137.
The seeds of Samh (Mesembryanthemum forsskalei) are Ostensibly Campylatropous as they seem externally anatropous but internally they have a curved embryo and both the seed body and the funicle exchange shapes. The embryo occupies a cylindrical seed body and is surrounded by a thin layer of endosperm; the major part of the endosperm occupies an ovoid bulge resembling a seed body.  相似文献   
138.
Abstract

Rapid clonal propagation potential of banana was investigated by using excised shoot tips of Musa spp. Shoot tips isolated from young suckers of ‘Anamur 2’, ‘Dwarf Cavendish’, and ‘Gazipasa 6'genotypes were used. Excised shoot tips were transferred immediately to Murashige and Skoog (MS) medium with different concentrations of 6-benzylaminopurine (BAP) and thidiazuron (TDZ) either alone or with indoleacetic acid (IAA). Rooting was achieved with indole-3-butyric acid (IBA) and α-naphthaleneacetic acid (NAA) in the presence or absence of activated charcoal (AC). The results showed that shoot proliferation rate was statistically affected by cytokinin types and their concentration. The responses to TDZ were better than to BAP. BAP or TDZ with IAA increased shoot elongation compared with BAP or TDZ alone. An increase in plant height, root numbers and average number of roots per explant was obtained using AC. Hence, for multiplication of ‘Dwarf Cavendish’, the use of MS medium with 2.5 µM TDZ with 1 µM IAA followed by rooting with AC only is recommended. For multiplication of banana genotypes ‘Anamur 2’ and ‘Gazipasa 6’, the use of MS medium with 1 µM TDZ and 1 µM IAA followed by rooting with AC only is recommended.  相似文献   
139.
The optical sensor for "tea catechins" was built by immobilizing 2,2'-(1,4-phenylenedivinylene)bis-8-hydroxyquinoline (PBHQ) on TiO? nanoparticles (NPs). The sensor worked by "indophenol blue" dye formation on PBHQ-immobilized TiO? NPs as a result of p-aminophenol (PAP) autoxidation with dissolved O? at pH 10. Among quercetin, rutin, naringenin, naringin, gallic acid, caffeic acid, ferulic acid, p-coumaric acid, catechin, epicatechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate, and trolox, only catechin group antioxidants delayed the color formation on NPs, as measured by the reflectance signal at 710 nm. For quantitative analysis, reflectance signal versus time was recorded, and the difference between the areas under curve (ΔAUC) in the presence and absence of catechin was correlated (r = 0.98) to catechin concentration. The selectivity of the sensor for catechins was shown in tea infusions compared to other plant extracts and was ascribed to the nonplanar structure of catechin interfering with the formation of perfectly conjugated indophenol blue on TiO? surface.  相似文献   
140.
Doepel  L  Cox  A  Hayirli  A  张树金 《饲料博览》2009,(9):43-43
试验旨在研究探讨日粮小麦对荷斯坦奶牛泌乳性能、瘤胃发酵和总营养物质消化率的影响。试验采用拉丁方设计,选择奶牛12头,随机分为3个处理组,分别添加蒸汽压片小麦0、10%、20%。奶牛每天饲喂和挤奶2次。选择6头奶牛安装瘤胃瘘管,瘤胃液样来自每个时期前2d的瘤胃液。试验结果表明,干物质采食量为20.9kg·d^-1,产奶量为36.1kg·d^-1,乳脂肪、乳蛋白、乳糖分别为1.25、1.10和1.67kg·d^-1,对其无显著影响。各处理间的乳脂率无显著差异,乳蛋白含量减少,10%组乳蛋白较20%组少(6.36,6.44)。与对照组相比,  相似文献   
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