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61.
62.
In unwounded soybean hypocotyls, pulse labelled with [14C]phenylalanine and inoculated with Phytophthora megasperma f.sp. glycinea, rates of [14C]-incorporation and glyceollin I accumulation were higher in resistant than in susceptible responses throughout the time-course of the experiment. This distinction was masked in hypocotyls that were wounded and inoculated. In such hypocotyls, high rates of [14C]-incorporation developed that were similar for the first 11 h in resistant and susceptible responses, although much more glyceollin I accumulated in the former. High rates of [14C]-incorporation also developed in uninoculated wounded hypocotyls but only small amounts of glyceollin I of high specific radioactivity were detected. Estimates of phenylalanine ammonia-lyase activity indicated that the metabolic flux through phenylalanine was limited in wounded controls but potentially very high in resistant responses. Differences in rates of [14C]-incorporation and in specific radioactivity of accumulated glyceollin I presumably indicate differences in the relative contributions of mobile internal pools and externally applied phenylalanine, in addition to rates of biosynthesis. Rapid decline in [14C]-glyceollin I was demonstrated in wounded controls in pulse-ch0ase experiments with phenylalanine as chase, but not in inoculated hypocotyls, due to continued [14C]-incorporation during the chase period. Rapid metabolism was demonstrated in all interactions and in wounds when cinnamic acid was used as the chase, but there was no evidence that differences in glyceollin I accumulation were due to differential rates of metabolism. Additional evidence for metabolic activity was provided by pulse feeding with [14C]glyceollin I. It is concluded that the stimulus of wounding or infection induces a metabolic pathway in which glyceollin I is not an end product. The accumulation of higher levels of glyceollin I in resistant than in susceptible responses appears to be due to earlier initiation and subsequently higher rates of biosynthesis in the former.  相似文献   
63.
Hazra B  Sarkar R  Bhattacharyya S  Roy P 《Fitoterapia》2002,73(7-8):730-733
The tumour-inhibitory effect of an ethanolic extract of chicory root was studied against Ehrlich ascites carcinoma in mice; significant results were obtained at doses from 300 to 700 mg/kg.  相似文献   
64.
Conservation tillage systems generally improve soil organic C (SOC), plant available water capacity (PAWC), aggregation and soil water transmission. A field experiment was conducted for 4 years (2001-2002 to 2004-2005) to study tillage (conventional tillage (CT) and zero tillage (ZT)) systems. The selected irrigation treatments were at four levels (I1: pre-sowing (PS), I2: PS + active tillering (AT)/crown root initiation (CRI), I3: PS + AT/CRI + panicle initiation (PI)/flowering (FL), and I4: PS + AT/CRI + PI/FL + grain filling (GF)), applied at the critical growth stages on rice (Oryza sativa L.) and wheat (Triticum aestivum L.). Their effects on direct seeded rice productivity and soil properties (SOC and selected physical properties) after rice and wheat harvest were investigated. Soil organic C contents after rice and wheat harvest in the 0-15 cm soil depth were higher under ZT than under CT. Soil organic C increased significantly with I2 over I1 for both crops and with I4 over I2 for the wheat crop. The PAWC was significantly higher with ZT than CT. Zero tilled and frequently irrigated plots showed enhanced infiltration characteristics (infiltration rate, cumulative infiltration and sorptivity) and saturated hydraulic conductivity. Both direct seeded rice and wheat yields were not significantly different in the plots under ZT and CT. There was a significant increase in both rice and wheat yields in the plots under I2 over I1. However, water use efficiency between irrigation treatments was not significantly different. Hence, under direct seeded rice-wheat system in a sandy clay loam soil of the sub-temperate Indian Himalayas, farmers may adopt ZT with two irrigations in each crop for optimum resource conservation.  相似文献   
65.
The photodegradation of aqueous alcoholic solutions of fenarimol at λ ≥ 250 nm has been examined. UV irradiation of an aqueous methanolic solution for 24 h yielded two photoproducts, identified as 2,4′‐dichlorobenzil and p‐chlorobenzoic acid, while irradiation of a solution in aqueous isopropanol yielded p‐chlorobenzoic acid and two additional products identified as 2,4′‐dichlorobenzophenone and o‐chlorobenzoic acid. A mechanism for the formation of the photoproducts is suggested. © 2000 Society of Chemical Industry  相似文献   
66.
The current study investigated the possibility of using the AMH concentration as a predictor of the ability of Korean Hanwoo cows to produce cumulus‐oocyte complexes, embryos that survive after transfer as well as the pregnancy outcome of surrogates. Eight sessions of ovum pick‐up (OPU) were performed with 19 donor cows at an interval of 3–4 days. Antral follicle count (AFC), oocyte quality and in vitro embryo development were recorded for each cow. Embryos produced from cows with different AMH profiles were transferred into recipients (n = 96). Cows in the high (≥0.25 ng/ml) and intermediate (0.1≥ to <0.25 ng/ml) AMH groups had a significantly higher AFC per OPU session (20.40 ± 1.36 and 16.91 ± 1.52, respectively; mean ± standard deviation) than cows in the low AMH group (<0.1 ng/ml; 12.19 ± 2.14). In addition, more cumulus‐oocyte complexes per donor were recovered in the high (11.46 ± 1.22) and intermediate (7.38 ± 0.83) AMH groups than in the low AMH group (4.77 ± 0.44). The percentage of oocytes reached blastocyst stage was significantly higher in the intermediate (47.0%) and high (38.5%) AMH groups than in the low AMH group (32.3%). The number of embryos produced per cow was higher in the high (3.9 ± 0.2) and intermediate (6.9 ± 0.6) AMH groups than in the low AMH group (2.2 ± 0.3). The percentage of embryos that gave birth to viable calves when transferred into recipients was higher for those derived from cows in the intermediate AMH group (50.7%) than for those derived from cows in the low (35.7%) and high (36.4%) AMH groups. In conclusion, a single measurement of AMH concentration predicted the in vitro embryo production potential of donor Korean native cows before OPU and is linked with embryo viability after transfer into recipients.  相似文献   
67.
Studies were conducted to examine the effect of flue gas carbon dioxide (CO2) on solubility and availability of different metals in fly ash of Powder River Basin (PRB) coal, Wyoming, USA. Initial fly ash (control) was alkaline and contains large amounts of water-soluble and exchangeable metals. Reaction of flue gas CO2 with alkaline fly ash resulted in the formation of carbonates which minimized the solubility of metals. Results for metal fractionation studies also supported this fact. The present study also suggested that most of the water-soluble and exchangeable metals present in the control (untreated) fly ash samples decreased in the flue gas-treated samples. This may be due to the transfer of the above two forms to more resistant forms like carbonate bound (CBD), oxide bound (OXD), and residual (RS). Geochemical modeling (Visual MINTEQ) of water solubility data suggested that the saturation index (SI) values of dolomite (CaMg(CO3)2) and calcite (CaCO3) were oversaturated, which has potential to mineralize atmospheric CO2 and thereby reduce leaching of toxic metals from fly ash. Results from this study also showed that the reaction of flue gas CO2 with alkaline fly ash not only control the solubility of toxic metals but also form carbonate minerals which have the potential to fix CO2.  相似文献   
68.
On 7 June 1972 the third , Jovian satellite Ganymede occulted the eighth-magnitude star SAO 186800. Successful photoelectric observations obtained at Lembang, Java (Indonesia), and Kavalur, India, show nonabrupt immersions and emersions, indicating the presence of an atmosphere whose surface pressure is greater than about 10(-3) millibar. By fitting the two occultation durations as chords to a model disk, the diameter is found to be 5270 (+30, - approximately 200) kilometers, the major error contribution arising from the uncertain atmospheric thickness below the occultation layer. The derived mean density is 2.0 (-0.03, + approximately 0.2) grams per cubic centimeter.  相似文献   
69.
70.
The potential of municipal solid waste compost (MSWC) was evaluated for rice cultivar, IET- 1444, during the wet seasons of 1997-99. Field experiments were conducted at the Agriculture Experimental Farm of Calcutta University, West Bengal, India using MSWC and cow dung manure (CDM), with or without urea (U), and fertilizers (F). Dry matter accumulation was highest with CDM + U, followed, in a descending order, by MSWC + U and F. Panicle length was largest and thousand–grain-weight were highest for F. Application of CDM alone gave 30% higher grain yield over MSWC but the latter, along with urea, increased grain yield by 49% over MSWC alone. Uptake of N by straw and grain was significantly higher with CDM as compared to MSWC. Percent N recovery was higher when fertilizer in the form of urea was applied with either CDM or MSWC. Uptake of heavy metals (Zn, Cu, and Pb) by straw and grain of rice was lower with the application of MSWC alone than with the other treatments except control. Uptake of Cd was below detection limit. There was no significant variation between the physico-chemical properties of soil due to the application of these treatments. Results indicated that MSWC application to rice was effective and safe to be used as an alternative organic supplement.  相似文献   
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