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91.
92.
Butorphanol tartrate (BT) was injected into mice before injection with acetylcholine in a murine model infected latently with pseudorabies virus. The analgesic effect and its influence on virus reactivation were observed. Mice preinjected with BT showed suppression of screaming, moving and excitation and the same level of movement after excitation as mice injected with PBS. In the group injected with BT i.p., one mouse died and another developed diarrhea with increased virus excretion. These results showed that BT has analgesic effects by both injection routes, s.c. and i.p.; however, BT induced death as a side effect, especially with i.p. injection. The injection route for BT should therefore be investigated further.  相似文献   
93.
Liming is a most fundamental agricultural practice for acid soils. Calcium and magnesium are necessary elements for plant growth. Strong acid soils, in addition to possible magnesium and/or calcium deficiency, may supply toxic amounts of trace elements to the plant. Soil testing has become an important factor for it indicates the need of lime and fertilizers. With advances in soil chemistry, many testing methods have been suggested and are being used. Advances have been made in the measurement of soil acidity, for instance, the “lime potential” theory of Schofield and Taylor (1,2) may provide basic information on that problem. In recent years there have been radical changes in the concept of exchangeable aluminum associated with the problem of soil acidity (3,5,5).  相似文献   
94.
The results of humus composition analysis of each fraction separated physically from each horizon of the five forest soils used in the last paper (3) were presented.

Regular changes in humus composition were observed with the gradation of horizons and With the decrease in particle size. Most of the humic acids from plant residual fractions belonged to the Rp type; hurnic acids from the L layers showed a tannin-like character which disappeared with the progress of decomposition, and humic acids from the smaller particle fractions of the layers contained a Pg fraction.

As for humic acids from the A horizon, they all belonged to the P or B type and contained a Pg fraction. In addition, it was concluded that the humification process in the mineral layer Was clearly different from that in the organic layer.  相似文献   
95.
Abstract

We devised a method to detect regions of phytosiderophore release from barley (Hordeum vulgare cv. Minorimugi) roots. Plants were grown in Fe-sufficient (+Fe) or Fe-deficient (?-Fe) water cultures for 14 d in a phytotron. Intact or excised roots were sampled and put between two sheets of filter papers just after the onset of the light period. The filter papers with roots were wrapped with vinyl film to avoid drying out and covered with aluminum foil to shade. The roots between the filter paper were kept in the phytotron for 4 h and phytosiderophores (PS) released from roots were absorbed by the filter paper. Then, the shape of the roots was preserved by photocopy and PS released on the filter paper were visualized by the method employed for detecting PS on thin layer chromatography (TLC). Gelatinous Fe solubilizing activity was employed for detecting PS on the filter paper. Released PS were detected as white spots on the orange-colored background and the regions of PS release from the roots were visible on the filter paper. It was evident that the apical zones of roots were the main regions of PS release. It was apparent that a distinct primary root newly formed on the basal parts had higher activity to release PS than the other roots of ?Fe plants. It was also shown that apical root zones of +Fe plants released PS.  相似文献   
96.
The serum carotenoid level gradually increased during the spawning migration of chum salmon (Oncorhynchus keta). Zeaxanthin, a yellowish carotenoid, was detected in the serum of spent males, while astaxanthin was a main carotenoid in the serum of males and females at other developmental stages. A high bilirubin level was found in the serum of spent males; the serum of spent male was yellow in colour due to the presence of zeaxanthin and bilirubin, although the serum of the other fish was bright orange.Three types of carotenoid-carrying lipoprotein such as low density lipoprotein, high density lipoprotein (HDL) and very high density lipoprotein fractions were present in the serum. Carotenoid-carrying lipoprotein from the HDL fraction became a main component during spawning migration. The serum bilirubin from the spent male salmon was distributed in the HDL fraction. Because bilirubin, as well as carotenoids, were present in the HDL fraction, the carotenoid-carrying lipoprotein from the HDL fraction was identical with bilirubin-binding protein in the serum of spent males. This carrier lipoprotein had two subunits (molecular weight 24,000 and 12,000); no disulfide bond was detected between the two subunits.  相似文献   
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Various sensors and analytic tools have been developed to assist with the collection and analysis of data regarding the activities of animals at pasture. We tested an accelerometry-based activity monitor, the Kenz Lifecorder EX (LCEX; Suzuken Co Ltd, Nagoya, Japan), to differentiate between foraging and other activities of beef cows in a steeply sloping pasture. Logistic regression (LR) and linear discriminant analysis (LDA), two of the most widely used techniques for distinguishing animal activities based on sensing device information, were employed in the analysis. An LCEX device was worn on a collar by each of four cattle over the course of 4 d, during which time the activity (foraging, resting, ruminating, walking, and grooming) of each cow was recorded by trained observers at 1-min intervals for a total of 15 h. LR and LDA were applied to the LCEX and observer data to distinguish between foraging and other activities. Overall, a more accurate measure was obtained by LDA (90.6% to 94.6% correct discrimination among cows) than by LR (80.8% to 91.8% correct discrimination). The threshold LCEX value for distinguishing between foraging and other activities varied among cows, and the correct discrimination rate for the pooled data set was 92.4% for LDA and 85.6% for LR. Based on individual cow LDA, the time spent foraging averaged between 443 and 475 min · d?1. Our results indicated that LCEX can be used to identify the foraging activity of cattle.  相似文献   
100.
Seasonal and spatial variability of litterfall and NO3 and NH4+ leaching from the litter layer and 5-cm soil depth were investigated along a slope in a tropical dry evergreen forest in northeastern Thailand. Using ion exchange resin and buried bag methods, the vertical flux and transformation of inorganic nitrogen (N) were observed during four periods (dry, early wet, middle wet, and late wet seasons) at 15 subplots in a 180-m × 40-m rectangular plot on the slope. Annual N input via litterfall and inorganic N leached from the litter layer and from 5-cm depth soil were 12.5, 6.9, and 3.7 g N m−2 year−1, respectively, whereas net mineralization and the inorganic N pool in 0–5-cm soil were 7.1 g N m−2 year−1 and 1.4 g N m−2, respectively. During the early wet season (90 days), we observed 82% and 74% of annual NO3 leaching from the litter layer and 5-cm soil depth, respectively. Higher N input via leaf litterfall in the dry season and via precipitation in the early wet season may have led to higher NO3 leaching rate from litter and surface soil layers during the early wet season. Large spatial variability in both NO3 vertical flux and litterfall was also observed within stands. Small-scale spatial patterns of total N input via litterfall were significantly correlated with NO3 leaching rate from the surface soil layer. In tropical dry evergreen forests, litterfall variability may be crucial to the remarkable seasonal changes and spatial variation in annual NO3 vertical flux in surface soil layers.  相似文献   
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