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111.
A series of 2-(1,3-dimethyl-4-substituted-5-pyrazolyl)sulfonylimino-5,7-disubstituted-2H-1,2,4-thiadiazolo[2,3-a]pyrimidines was synthesized and tested for herbicidal effects. The compounds showed potent activity and improved selectivity to rice when compared with analogous sulfonylurea derivatives.  相似文献   
112.
To evaluate the efficiency and accuracy of estrous detection using a new pedometry system that can measure the hourly activity of cattle, pedometers were attached to the neck and the hind legs of 15 Holstein heifers. Heifers were reared in pasture for grazing, an open paddock, or in a tie-stall barn (an additional pedometer was attached to a front leg of each of these heifers). The most recent 24 h-total number of steps was compared for each 1 h-interval with the mean value of the preceding days during the reference period (RP). The neck pedometer detected all 10 instances of estrous activity (100%) for the grazing heifers at 1.3 times the thresholds value for a 5-day RP but with only 32% accuracy. The hind leg pedometer, however, obtained 100% efficiency and 83% accuracy at 1.4 times the threshold value for a 7-day RP. The efficiencies and accuracies in detecting 12 instances of estrous activity under the paddock condition were 92 and 65% (neck, 1.3-fold, 7-day RP) and 92 and 100% (hind leg, 1.6- or 1.7-fold, 7-day RP), respectively. Under the tie stall condition, the neck pedometers detected 92% of 23 instances of estrous activity with 34% accuracy (1.2-fold, 3-day RP), and the efficiencies and accuracies of the leg pedometers were 78 and 78% (hind leg, 1.4-fold, 4- or 6-day RP) and 87 and 83% (front leg, 1.4-fold, 7-day RP), respectively. Prediction of ovulation time was more precisely with the leg pedometers than with those under the tie stall conditions. Our preliminary results indicate that this new pedometer system has practical value for estrous detection in heifers under different rearing conditions, which affect the criteria required for detection. Furthermore, they also indicate that a leg pedometer can reliably detect estrus and that a neck pedometer may only be capable of detecting estrus under paddock rearing conditions.  相似文献   
113.
Acetamiprid, (NI-25; (E)-N1-[(6-chloro-3-pyridyl)methyl]-N2-cyano-N1-methylacetamidine), is a novel neonicotinoid insecticide having an N-cyanoacetamidine structure as its characteristic feature. The [1H] and [13C]-NMR spectra indicated the existence of two different structures in acetamiprid at room temperature in solution. The measurement of CH-NOE and C–C coupling constants proved the E-configuration at the cyanoimino group in both existing structures. The [13C] chemical shifts of N-CH3 and the long range C–H coupling in the formamidine analogue of acetamiprid suggested that there exist two conformers generated by the rotation of C–C single bond in the amidine moiety. Dynamic NMR spectra of acetamiprid and the computer simulation of the two-site exchange demonstrated that the two conformers change slowly to each other at room temperature. The conformational analysis by semi-empirical molecular orbital calculations using MNDO-PM3 method predicted four conformers as energy-minimum structures, among which two E-conformers were more stable than Z-conformers. One of the E-conformers in which two methyl groups are in cis configuration was superimposable onto the structure of imidacloprid, which is a known neonicotinoid insecticide having more rigid structure. This E-conformer was assumed as the active conformation of acetamiprid on the basis of the molecular similarity in terms of steric and electrostatic properties. © 1997 SCI  相似文献   
114.
Reforestation in the humid tropics and arid zones, where trees are often subject to stresses, is an effective approach for mitigating global warming. Forestation with Populus species that are tolerant to the stresses in such regions has been conducted. The selection of poplar trees with higher stress tolerance leads to more efficient reforestation. The genome-wide bioinformatics approaches of gene function have been used for revealing the mechanisms of biological processes, including such stress tolerance. The decoding of the poplar genome has been followed by the genome-wide identification of genes and then the inference of gene function for systematic understanding of biological processes. To predict gene function in poplar, we analyzed poplar gene expression data using DNA microarray datasets obtained from the Gene Expression Omnibus database and developed a database for poplar gene co-expression analysis. Using the database, we illustrate the steps to retrieve two groups of co-expressed genes that are specifically expressed in experiments of hypoxic stress response in gray poplar, a flooding-tolerant tree species. Our database allows users to extract genes involved in biological processes, such as stress reaction, and then is useful for understanding such mechanisms in tree species.  相似文献   
115.
116.
Depending on the initial stocking density, ocellate puffer larvae exhibit the cannibalism that resulted in high mortality. We aimed to clarify the relationship between stocking density of larvae, mortality, and the effect of density on cannibalism. Ocellate puffer larvae were reared at five different stocking densities between 5 and 25 larvae/L with duplicate 1‐m3 tank for each treatment. Larvae were stocked at 0 d after hatch (d.a.h.), and the experimental cultures lasted for 55 d. In larvae stocked initially at more than 10 larvae/L, cannibalism was evident from 11 to 17 d.a.h., and the survival rate at 55 d.a.h. was less than 15%. The survival rate was 25.5% at 5 larvae/L, and cannibalism was observed from 31 to 32 d.a.h. Consequently, an initial density of 5 larvae/L was the most efficient in terms of survival and the prevention of cannibalism. On the other hand, when cannibalism is still observed at 5 larvae/L, it is necessary to lower the stocking density before the onset of cannibalism.  相似文献   
117.
We examined the effect of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on the rates of abnormal morphology in juvenile brown sole Pseudopleuronectes herzensteini. Larvae during the D–E stages (15–24 days post hatching) were fed live food containing various amounts of DHA and/or EPA prepared using emulsified oils (DHA ethyl ester, EPA ethyl ester, and corn oil). Larvae during the F–I stages were fed Artemia enriched with a commercial diet supplement. We found that DHA and EPA promoted larval development and improved the incidence of morphological abnormalities in brown sole juveniles to a similar extent. However, DHA was more effective than EPA in preventing the appearance of morphological abnormalities in brown sole. The incidence of normal morphology was clearly improved by an increase of the DHA content in brown sole larvae at 25 days post-hatching. These results suggest that it is important to promote larval development and feed larvae with live food containing high levels of DHA during the D–E stages to prevent morphological abnormalities in brown sole juveniles.  相似文献   
118.
Siratro (Macroptilium atropurpureum), desmodium (Desmodium intortum), and soybean (Glycine max) were grown in pots with or without irrigation for 20 d at the vegetative growth stage in order to examine the effects of water stress on the leaf water potential, stomatal conductance, biomass production, biological nitrogen fixation, and nitrogen accumulation. Whole plant weight decreased under water stress conditions and the decrease was less pronounced in siratro than in desmodium and soybean. Decrease in total leaf area was the largest and dry matter partition to stem and petioles was the highest in siratro. Decrease in leaf water potential was lower in desmodium and soybean than in siratro. Although water stress decreased biological nitrogen fixation in all the species, the decrease was relatively less pronounced in siratro than in desmodium and soybean. Whole plant nitrogen concentration was higher in siratro than in soybean and desmodium. The results indicated that siratro is more tolerant to water stress than soybean and desmodium. This could be partially attributed to the maintenance of a higher water potential and higher biological nitrogen fixation by siratro under water stress conditions.  相似文献   
119.
Chiroptera is thought to be a vector or a natural reservoir of various pathogenic microbes. However, there are few basic studies on the subject of chiroptera immune systems. This is the first report to determine the sequence of bat CD4 cDNA. Comparison with other animals' CD4 and phylogenetic analysis have shown that bat CD4 had a higher homology to cat and dog CD4 than to human and mouse CD4. Moreover, from the analysis of the structure of the CD4 Ig-like C-type 1 region, in bat CD4 there was an insertion of 18 extra amino acids. In addition, bat CD4 lacked cystein, which suggested that the disulfide bond could not be formed. Human, monkey and mouse CD4 have the cystein and the disulfide bond, but pig, cat, whale and dog CD4, like that of the bat, lacked the cystein. We conducted the present study in order to help elucidate the infectious diseases derived from the bat as well as bat immune systems.  相似文献   
120.
Due to the long parturition period of raccoons, we assumed that age at first conception of late born females was later than that of early born females. From March 2005 to September 2008, 201 females estimated to be younger than 24 months were separated into early- and late-born groups on the basis of their estimated birth month (to the nearest 2 months), and parous status and body mass index (BMI) were examined. Age at first conception of late-born females (over 18 months old) was estimated to be later than that of early-born females (over 12 months old). The average BMI in early-born individuals at 12 months old might have affected their ability to conceive because of body fat deposition.  相似文献   
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