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71.
Two‐year‐old seedlings of Pinus brutia, P. brutia var. eldarica, Pinus pinea and 3‐year‐old seedlings of Pinus radiata, Pinus sylvestris, Pinus nigra and Cedrus libani were inoculated on the lower stem with isolates of Heterobasidion annosum s.s. collected from the Black Sea and Mediterranean regions of Turkey. In total, 315 seedlings were inoculated in April 2014 and incubated in a growth chamber for 7 weeks at 18–20°C. All isolates were pathogenic on the seven different hosts and had the ability to grow in living sapwood. The isolates had a greater growth on C. libani, P. sylvestris and P. radiata seedlings compared to plants of the other species tested. The least affected species were P. brutia and P. nigra. The isolates originating from the Black Sea region caused longer lesions on the hosts. Overall mortality during 7 weeks of incubation was 4%.  相似文献   
72.
The nutritional quality of acid‐modified poultry manure biochar is unclear, so a better understanding of its properties and agronomic potential is needed. The biochar was modified with phosphoric acid (H3PO4) and nitric acid (HNO3) and a combination of the two, before and after pyrolysis. After characterization of biochar samples and determination of total and water‐soluble mineral element concentrations, biochars were applied to a calcareous soil at a rate of 0.5% (w/w) to find out their effects on the mineral nutrition and growth of maize. Treatment with H3PO4+ HNO3 enriches the biochar with phosphate, nitro groups and nitrate. The experimental results suggested that biochar modified with HNO3 and/or HNO3+H3PO4 after pyrolysis increased the water‐soluble phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu) and manganese (Mn) concentrations and increased plant‐available nutrients and plant growth by positively affecting the absorption of plant nutrients. The highest plant dry weight was obtained from biochar post‐treated with HNO3+H3PO4, and this was followed by HNO3‐ and H3PO4‐modified biochars. Premodification with HNO3+H3PO4 also significantly increased plant dry weights. The results of this study revealed that poultry manure biochar modified with HNO3 and H3PO4 can be used effectively in calcareous soil for the improvement of plant mineral nutrition.  相似文献   
73.
To test how efficiently plantations and seed orchards captured genetic diversity from natural Anatolian black pine (Pinus nigra Arnold subspecies pallasiana Holmboe) seed stands, seed sources were chosen from 3 different categories (seed stands (SS), seed orchards (SO) and plantations (P)) comprising 4 different breeding zones of the species in Turkey. Twenty-five trees (mother trees) were selected from each SS, SO and P seed sources and were screened with 11 Random Amplified Polymorphic DNA (RAPD) markers. Estimated genetic diversity parameters were found to be generally high in all Anatolian black pine seed sources and the majority of genetic diversity is contained within seed sources (94%). No significant difference in genetic diversity parameters (numbers of effective alleles, % of polymorphic loci and heterozygosity) among seed source categories was found, except for a slight increase in observed heterozygosities in seed orchards. For all seed source categories, observed heterozygosity values were higher (Ho = 0.49 for SS, 0.55 for SO and 0.49 for P) than expected ones (He = 0.40 for SS, 0.39 for SO and 0.38 for P) indicating the excess of heterozygotes. In general, genetic diversity in seed stands has been transferred successfully into seed orchards and plantations. However, the use of seeds from seed orchards can increase the amount of genetic diversity in plantations further. The study also demonstrated that number of plus-tree clones (25–38) used in the establishment of seed orchards was adequate to capture the high level of diversity from natural stands.  相似文献   
74.
In the present study, 13 clinical cases of canine mammary adenocarcinoma were evaluated in order to understand the effect of Tarantula cubensis extract (TCE) on tumor tissue. Punch biopsies were taken from the tumors before treatment with TCE. Subcutaneous injections of TCE were administered three times at weekly intervals (3 mL per dog). Between days 7 and 10 after the third injection, the tumor masses were extirpated by complete unilateral mastectomy. Pre- and post-treatment tumor tissues were immunohistochemically assessed. The expression of B-cell lymphoma 2 (Bcl-2) was found to be higher in pre-treatment compared to post-treatment tissues (p < 0.01) whereas Ki-67 expression was lower in post-treatment tissues (p < 0.01). No significant differences in fibroblast growth factor or vascular endothelial growth factor expression were observed between pre- and post-treatment tissues (p > 0.05). The apoptotic index was determined to be low before treatment and increased during treatment. These results suggest that TCE may be effective for controlling the local growth of canine mammary adenocarcinoma by regulating apoptosis.  相似文献   
75.
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   
76.
We studied the oxidative stress and osmoregulatory damage as well as the accumulation of lead in Mozambique Tilapia Oreochromis mossambicus exposed to different sublethal concentrations—low, medium, and high (0.5, 2.5, and 5.0 mg/L)—of waterborne lead for 14 d in a semistatic condition. The accumulated levels of Na+,K+-ATPase, glutathione (GSH), and thiobarbituric acid reactive substances (TBARS) were determined from samples of gill, liver, intestine, brain, kidney, and muscle tissues. At the end of the experiment, the GSH levels of most tissues were higher in the treated group than in the control group (especially in the liver and kidney) but lower in the intestine. The levels of TBARS in the gill and brain tissues of the fish exposed to high lead doses were significantly higher than those of fish in the control group. Na+,K+-ATPase activity seemed to be significantly inhibited in the gill, intestine, and brain tissues across all treatment groups. At the end of the study, the total amount of lead that had accumulated within the various tissues ranked as follows: intestines > kidney > brain > gill > liver > muscle. Our findings suggest that sublethal concentrations of lead can disrupt the health of Mozambique Tilapia and cause oxidative stress and osmoregulatory damage.

Received March 30, 2014; accepted November 28, 2014  相似文献   

77.
The specification and maintenance of growth sites are tightly regulated during cell morphogenesis in all organisms. ROOT HAIR DEFECTIVE 2 reduced nicotinamide adenine dinucleotide phosphate (RHD2 NADPH) oxidase-derived reactive oxygen species (ROS) stimulate a Ca2+ influx into the cytoplasm that is required for root hair growth in Arabidopsis thaliana. We found that Ca2+, in turn, activated the RHD2 NADPH oxidase to produce ROS at the growing point in the root hair. Together, these components could establish a means of positive feedback regulation that maintains an active growth site in expanding root hair cells. Because the location and stability of growth sites predict the ultimate form of a plant cell, our findings demonstrate how a positive feedback mechanism involving RHD2, ROS, and Ca2+ can determine cell shape.  相似文献   
78.
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   
79.
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   
80.
Direct use of poultry manure on agricultural lands may cause environmental concerns, so there is a need to establish the suitability of the application of biochar derived from poultry manure for calcareous soil chemical properties and plant growth. The purpose of this study was to evaluate the effects of processed poultry manure (0, 5, 10 and 20 g/kg) and its biochar (0, 2.5, 5, 10 and 20 g/kg) on soil chemical properties of a calcareous soil and growth of bean (Phaseolus vulgaris) and maize (Zea mays) plants. In the incubation experiment, both processed poultry manure (PPM) and biochar decreased pH and the concentration of plant‐available Fe of soil but increased plant‐available P, Zn, Cu and Mn concentrations. PPM and biochar increased the concentrations of exchangeable cations (K, Ca and Mg) in soil. PPM and biochar applications increased the growth of maize and bean plants. PPM and biochar resulted in increased concentrations of N, P, K, Ca, Fe, Zn, Cu and Mn in bean plants. In maize plants, PPM and biochar applications increased the N, P, K, Zn, Cu and Mn but decreased the Ca and Mg concentrations. Results of this study reveal that poultry manure biochar can be used effectively for agricultural purposes.  相似文献   
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