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81.
A hospital‐based case study was conducted at the University of Veterinary Medicine Vienna for a 1‐year period. The purpose of this study was to determine possible alterable and non‐alterable risk factors of equine colic in Austria. The investigated parameters were obtained from hospital medical records (individual factors, duty of the horse, deworming, change in diet and water intake), from questionnaires (feed intake, watering types, housing and pasture practices) and from http://www.orf.at (weather‐related factors). Moreover, 221 collected feed samples were investigated through hygienic quality sensory evaluation and mould, yeast and bacteria presumptive samples were confirmed by microbiological investigation. Variables that were observed from the hospital medical records and found to be significantly associated with colic in a univariate analysis were included in multivariate analysis and the only remaining risk factor was decreased water consumption (p < 0.001, OR = 5.025). Consequently, a total of 2743 horses and 366 cases of colic were observed during the study period. The risk factors for colic in Austria were identified for the first time in this study and these increased risk factors were decreased water consumption, high amount of concentrate intake (p = 0.037), low hygienic quality of hay (p = 0.027) and high temperature on the arrival date (p = 0.003). Results suggest that the occurence of colic may not stop, but may decrease with better feed management practices in Austria.  相似文献   
82.
Uterine tissue from pregnant bitches was investigated by qualitative RT-PCR for the gene expression of local factors potentially important for the implantation of canine embryos. For this purpose, 10 bitches identified as being at the time of implantation or early placentation by means of ultrasonography before ovariohysterectomy (days 20–35, n = 10) provided tissues for comparison to tissue collected in a previous study and identified as early pregnant (n = 10) or non-pregnant (n = 4) by embryo flushing after ovariohysterectomy (days 10–12 after mating; Schäfer-Somi et al. 2008 ). Uterine tissue was excised from the middle of the left horn from early pregnant and non-pregnant animals, including from interplacental and placentation sites. The following genes were investigated: CD-4, -8; cyclooxygenase (COX)-1, -2; granulocyte macrophage-colony stimulating factor (GM-CSF); hepatocyte growth factor (HGF); insulin-like growth factor (IGF)-1, -2; transforming growth factor (TGF) and tumour necrosis factor (TNF)-α; interferon (IFN)-γ; interleukin (IL)-1β, -2, -4, -6, -8, -10, -12; leukaemia inhibitory factor (LIF) and leptin. Gene expression for CD-8, COX-1, TGF-β, HGF, IGF-1, IL-2, -4,-10, IFN-γ and LIF were detected in the pre-implantation uterus, and all except IL-2 and -10 were still detectable during the implantation and placentation stage. During implantation, mRNA for IGF-2 and GM-CSF were additionally detected. The dioestrous uterus differed from the pregnant uterus because of the absence of CD-8, IL-4 and IFN-γ and the expression of CD-4, TNF-α and IL-6. The results suggest that IL-4, IFN-γ, CD-8, GM-CSF and IGF-2 are regulated in a pregnancy-specific manner and that GM-CSF and IGF-2 probably have growth supporting and immune modulating functions during implantation of the canine embryo.  相似文献   
83.
Interactive effects of silicon (Si) and high boron (B) on growth and yield of tomato (Lycopercison esculentum cv. ‘191 F1’) plants were studied. Treatments were: 1) control (B1), normal nutrient solution including 0.5 mg L?1 B (boron), 2) B1 +Si treatment: 0.5 mg L?1 boron plus 2 mM Si, 3) B2 treatment: 3.5 mg L?1 B, 4) B2 +Si treatment: 3.5 mg L?1 B plus 2 mM Si, 5) B3 treatment: 6.5 mg L?1 B, and 6) B3 +Si: 6.5 mg L?1 B plus 2 mM Si. High B reduced dry matter, fruit yield and chlorophyll (Chl) in tomato plants compared to the control treatment, but increased the proline accumulation. Supplementary Si overcame the deleterious effects of high B on plant dry matter, fruit yield and chlorophyll concentrations. High B treatments increased the activities of superoxide dismutase (SOD; EC 1.15.1.1), peroxidase (POD; EC. 1.11.1.7) and polyphenol oxidase (PPO; EC 1.10.3.1). However, supplementary Si in the nutrient solution containing high B reduced SOD and PPO activities in leaves, but POD activity remained unchanged. These data suggest that excess B-induced oxidative stress and alterations in the antioxidant enzymes. Boron (B) concentrations increased in leaves and roots in the elevated B treatment as compared to the control treatment. Concentrations of calcium (Ca) and potassium (K) were significantly lower in the leaves of plants grown at high B than those in the control plants. Supplementing the nutrient solution containing high B with 2 mM Si increased both nutrients in the leaves. These results indicate that supplementary Si can mitigate the adverse effects of high B on fruit yield and whole plant biomass in tomato plants.  相似文献   
84.
Cucumber (Cucumis sativus) was field grown from April 2001–July 2001 to determine the effects of mulch, irrigation regime, and potassium (K) rates on yield and related traits (i.e., leaf relative water content, water-use efficiency, and macronutrition). This was a factorial experiment with two irrigation levels (125% A pan daily versus 75% A pan every three days), two mulch levels (mulched versus unmulched), and three K2O levels (20, 40, or 60 g/m2). Plants receiving reduced water application (75% A pan every 3 days) showed significant reductions in all parameters when compared with well-watered plants (125% A pan daily). The use of black polyethylene mulch (BPM) covers improved the plant dry matter, chlorophyll concentrations, fruit yield, and relative water content in leaves of well-watered plants and also improved K availability to the plants by keeping soil moisture higher than that of stressed plants without mulch. Using BPM increased plant water-use efficiency compared with that under the reduced water (RW) treatment. Reduced water application enhanced electrolyte leakage compared with that recorded under the well-watered (WW) treatment. Mulching decreased electrolyte leakage under the RW treatment. Increased K rates significantly enhanced leaf K in the mulched and WW plants. However, increased K rates did not increase leaf K in the RW plants. Reduced water application reduced leaf concentrations of all nutrients tested, i.e., nitrogen (N), phosphorus (P), K, calcium (Ca), and magnesium (Mg). However, mulching enhanced the concentrations of these elements, although their concentrations were still lower than those under the WW treatment. These results clearly indicate that field-grown number plants under mulched treatments were less stressed under semi-arid conditions and also that mulched treatments increased K availability to the plants.  相似文献   
85.
The effect of silicon (Si) on physiological attributes and nutritional status of maize (Zea mays cv. DK 647 F1) under water stress was studied in a pot experiment. Treatments were (1) well watered (WW): 100% of FC (soil field capacity), (2) WW + Si1: 100% of FC + 1 mM Si, (3) WW + Si2: 100% of FC + 2 mM Si, (4) water stress (WS): 50% of FC, (5) WS + Si1: 50% of FC + 1 mM Si and (6) WS + Si2: 50% of FC + 2 mM Si. In the control treatment, plants were irrigated to field capacity (100% FC). Water stress was imposed by maintaining a moisture level equivalent to 50% of field capacity, whereas the well-watered pots (control) were maintained at full field capacity. Water stress was found to reduce the total dry matter (DM), chlorophyll content, and relative water content (RWC), but to increase proline accumulation and electrolyte leakage in maize plants. Both Si treatments largely improved the above physiological parameters, but levels remained significantly lower than the control (WW) values except for electrolyte leakage and root:shoot ratios, which were higher. Only root DM appeared to show very little variation in any of the treatments. The concentration of Si in the plants was increased by Si addition into the nutrient solution. Water stress reduced leaf calcium (Ca) and potassium (K) of maize plants, but addition of Si increased these nutrient levels; Ca levels were similar to WW under the high-Si treatment, but K was lower. Root Ca and K were both increased by WS; root Ca was further increased by high Si (WS + Si2 treatment). Addition of Si to the WS treatments did not change root K. Results indicate that while application of Si may be one approach to improve growth of this crop and increase its production in arid or semi-arid areas where water is at a premium, this technique would not fully substitute for an adequate water supply.  相似文献   
86.
Among domestic animals, teat order is only observed in the pig. In order to achieve the healthy growth and weaning of piglets, it is important to elucidate if volume of colostrum secretion and immunoglobulin A (IgA) and IgG concentrations differ among the teats of a sow. Nine sows were used to evaluate the difference in colostrum secretion volume (CSV) and four of these sows were assessed for IgA and IgG concentrations from each teat. Samples were collected five times during 21 h following parturition. Teats were assigned anatomical locations of teat (1 to 7) from anterior to posterior. The CSV of anterior (locations 1 and 2) and middle teats (locations 3–5) was significantly higher than those of posterior teats (locations 6 and 7) throughout the experiment except for 18 h post‐parturition (P < 0.05). The CSV of the teats at location 1 was significantly higher at most collection times than those at locations 6 and 7. A positive correlation of CSV was observed with IgA and IgG concentrations from 12 h and 6 h post‐parturition, respectively (P < 0.05). The results suggest that anterior teats secrete greater volumes of colostrum and that these tend to contain higher IgA and IgG than posteriors teats.  相似文献   
87.
Lipoprotein aggregation is generated by hydrophobic nature of lipoproteins that is known to be one of the causes of atherosclerosis. Low density lipoproteins (LDL) has been extensively studied in this respect but not chylomicrons. There is strong evidence that post‐prandial triacylglycerol‐rich lipoproteins are atherogenic. Because biophysical properties of lipoproteins are largely determined by their lipid compositions, hydrophobic nature of thoracic lymph duct chylomicrons obtained from rats given different fats or oils by gavage was investigated by vortexing‐induced aggregation and hydrophobic interaction chromatography. Contrary to LDL, vortexing did not cause aggregation in chylomicrons. Vortexing of fish oil and butter chylomicrons resulted in more prominent reduction in absorbances compared with chylomicrons from other sources that might indicate less micelle stability. Hydrophobic interaction chromatography of fish oil, palm oil and olive oil chylomicrons yielded three fractions, whereas that of sunflower, margarine and butter chylomicrons gave rise to two fractions. These results suggest that surface hydrophobicity of chylomicrons might be heterogenous. Our results also demonstrate that fish oil chylomicrons have less hydrophobicity and lower stability against vortexing compared with chylomicrons from other sources. Considering beneficial effects of fish oil in cardiovascular health, less hydrophobicity together with lower stability might provide an additional atherogeneicity index for lipoproteins.  相似文献   
88.
The effects of zinc and vitamin A supplementation to the diet on some blood metabolites were evaluated in Hisex brown laying hens from 56 weeks to 68 weeks of age. A total of 130 birds were divided into two main groups according to vitamin A treatment (0 and 3.44 mg retinyl acetate kg(-1) feed, respectively), each consisting of 65 hens. Hens in both of the main groups were then divided into five zinc treatment groups (0, 25, 50, 100 and 200 mg zinc kg diet(-1) respectively) of 13 hens each. It was observed that plasma T4, T3 and total cholesterol levels were affected by only zinc supplementation. While 100 and 200 mg Zn kg(-1) decreased plasma T4 level compared to control value, plasma T3 level was reduced by 100 mg Zn kg(-1) compared to groups fed less Zn. Adding 50 and 200 mg Zn kg(-1) to the diet increased plasma total cholesterol level in the birds compared to other groups. Vitamin A, zinc, and their interaction did not influence the concentration of plasma high-density lipoprotein (HDL)-cholesterol, glucose and egg yolk cholesterol in laying hens.  相似文献   
89.
The aim of this study was to investigate effects of an organophosphate insecticide, diazinon (DI), on pancreas, and possible ameliorating role of vitamins E and C. We examined both in vivo and in vitro effects of DI on serum activities of alkaline phosphatase (ALP), γ-glutamyltransferase (GGT), amylase, and lipase enzymes. We also evaluated possible ameliorating effects of vitamins E and C combination against DI toxicity and blood levels of thiobarbituric acid reactive substances (TBARS) only in vivo. In vivo experimental groups were: control group, DI-treated group, and DI + vitamins E plus C-treated group. In vitro study groups were: control group and DI-treated group. The biochemical analyses were determined in in vitro experiments at both hour 0 and 24 while in in vivo experiments were determined only at hour 24. Lipase activity and TBARS level were found increased by DI in in vivo experiments while lipase activity was found decreased in in vitro experiments. Amylase and ALP activities were found decreased by DI in both in vivo and in vitro experiments. Also, the combination of vitamins E and C was found to partially improve these disorders. These results suggest that DI treatment causes pancreas damage via increasing oxidative stress in rats, and a combination vitamins E and C can reduce this lipoperoxidative effect.  相似文献   
90.
The aim of the current study was to determine whether a rumen protected palm oil based diet affect malondialdehyde (MDA), glutathione peroxidase (GSH-Px), reduced glutathione (rGSH) and vitamin A levels in the tissues of cornu uteri, corpus uteri and corpus luteum over the barley based isoenergetic and isonitrogenous diet, and whether the response is different between ewes and ewe-lambs. During the breeding season, half of Morkaraman ewes (2-4-year-old, n = 10) and ewe-lambs (7-8-months-old, n = 10) was offered a barley based diet and the other half was offered a protected palm oil based diet for 42 +/- 0.7 days. At the end of the experiment all animals were slaughtered and measurements carried out in the tissues collected. In all animals tested, cornu uteri had the highest MDA levels followed by corpus uteri and corpus luteum (P < 0.01) but no differences were between the tissues observed in GSH-Px and rGSH levels (P > 0.05). Vitamin A levels were, however, higher in corpus luteum than in cornu uteri and corpus uteri (P < 0.05). Corpus uteri MDA levels were not different (P > 0.05) but rGSH levels were higher for the palm oil fed groups (P < 0.05). GSH-Px and rGSH levels were higher for ewe-lambs than ewes (P < 0.05). In conclusion, it appears that MDA, rGSH, GSH-Px, and vitamin A work in a different fashion for corpus uteri, cornu uteri and corpus luteum, and for ewes and ewe-lambs. Dietary palm oil did not significantly affect the parameters studied except higher rGSH levels in corpus uteri. Levels of antioxidatively active substances, such as rGSH and GSH-Px were lower in ewes compared with those in ewe-lambs.  相似文献   
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