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51.
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The captive bolt device has been used for stunning cattle at abattoirs for more than 100 years and is now one of the stunning devices used most widely. The aim of this review article was to assess the effects that are decisive during cattle slaughter on the quality of stunning with the use of a captive bolt stunning device. The basis of effective stunning is the use of a suitable type of device, with the speed of the bolt and the kinetic energy corresponding to the anatomical parameters of the slaughtered animal. The importance of the regular cleaning and maintenance of stunning devices and monitoring of the effectiveness of stunning goes without saying. The immediate loss of sensibility in the animal must occur after the first shot. The effectiveness of the stunning process can be quantified by regular monitoring of the behavior of animals after stunning with an emphasis on the loss of reflexes (corneal reflex, regular breathing, attempts to regain physiological posture) and checks on the shot location on the skulls of slaughtered animals.  相似文献   
53.
The interaction of folpet with the glutathione-dependent enzyme demethylation of fenitrothion was studied. In a reaction catalyzed by methyltransferase from rat liver in the presence of 0.3 μmol of glutathione, 0.21 μmol of folpet caused a 100% inhibition of the demethylation of 0.2 μmol of fenitrothion. A parallel study was made on the qualitative and quantitative course of the reaction between folpet and glutathione. Phthalimide was formed as the main degradation product of folpet, but the composition of the degradation products of glutathione was dependent on the molar ratio of the reactants. Compounds absorbing at 267 nm (probably derivatives of 2-thiazolidinethiones) were formed when the ratio of glutathione to folpet was 4.5:1. When this ratio was reversed, oxidized glutathione was the main product. From observations on the course of the enzymatic demethylation of fenitrothion and on the degradation of folpet by glutathione, it appears that in the enzyme demethylation system, the reaction between fungicide and glutathione predominates.  相似文献   
54.
The study evaluated dietary supplementation with live yeast (LY) Saccharomyces cerevisiae (CNCM I‐4407, 1010 CFU/g, Actisaf; Phileo Lesaffre Animal Care, France) on rumen fermentation and serum metabolic profile in lactating dairy cows. Fifty Holstein cows received a total mixed ration with (Live Yeast Diet, LYD, n = 25) or without (Control Diet, CD, n = 25) 5 × 1010 CFU/cow/day of LY from 3 to 19 weeks of lactation. Rumen fermentation and serum metabolic profile were measured in eight cows per treatment at 3, 7, 11, 15, 19 weeks post‐partum. LYD showed an increased daily milk yield (+4%) over CD (p < 0.05). Mean rumen pH at 4 hr after morning meal was higher in LYD (6.59) than CD (6.32) (p < 0.01). Total volatile fatty acids (VFA) and acetate molar proportion were higher in LYD (114.24 mM; 25.04%) than CD (106.47 mM; 24.73%) (p < 0.05). Propionate and butyrate molar proportions, acetate to propionate ratio, ammonia levels did not differ between LYD and CD. Ruminal lactate was lower in LYD than CD (9.3 vs. 16.4 mM) (p < 0.001), with a 53% decrease in LYD. During peak lactation, LYD had lower serum NEFA (p < 0.05, 0.40 vs. 0.48 mM) and BHBA (p < 0.01, 0.47 vs. 0.58 mM) than CD, lower liver enzyme activities (AST 1.39 vs. 1.54 ukat/L) (p < 0.05). Serum glucose was higher in LYD at peak lactation (3.22 vs. 3.12 mM, and 3.32 vs. 3.16 mM respectively) (p < 0.05). The results confirmed a reducing effect of LY on lactate accumulation in rumen fluid, associated with an increase in rumen pH. Lower serum levels of lipomobilization markers, liver enzyme activities and higher glucose levels may suggest that live yeast slightly mitigated negative energy balance and had a certain liver protective effect.  相似文献   
55.
Summary The development and localization of phenolic compounds in sapwood and heartwood of Abies alba Mill. have been studied using cytological and UV-microspectrophotometric methods. The synthesis of phenolic substances was apparently initiated in vesicles developing from rough ER of the ray parenchyma cells in sapwood. They are different from the phenolic material in the pit membrane and cell wall of heartwood. There was no indication to suggest that the polyphenols in the cell wall of heartwood were either derived from or identical with the phenolic substances in the lumina of ray cells.Dedicated to Prof. Dr. H. von Pechmann on the occasion of his 70th birthdayWe are thankful to Professor Dr. Walter Liese for his support and to Mrs. R. Schultze and Miss R. Endeward for technical assistance.  相似文献   
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The homogeneity of analytical samples and the stability of pesticides during the sample processing of oranges and tomatoes were evaluated. The mean concentrations of 14C-labeled chlorpyrifos in analytical portions (subsamples) after processing show that homogeneity is dependent on sample type as well as the processing procedure. The homogeneity of analytical samples of tomatoes processed cryogenically was much better than those processed at ambient temperature. For tomatoes, the minimum analytical portion masses required for between-analytical portion variation of < 0.3 Ho were 110 and 5 g for processing at ambient and cryogenic temperatures, respectively. Results for orange showed that analytical portion sizes of 5 g provided sufficient homogeneity from both sample processing procedures. Assessments of pesticide stability demonstrated that most were relatively stable during processing at either ambient or cryogenic temperatures. However, some pesticides, including dichlofluanid, chlorothalonil, tolylfluanid, and dicloran, appeared to suffer much greater losses (>20%) during processing at ambient temperature. For these analytes, loss is interpreted as chemical degradation.  相似文献   
58.
Model projections suggest that although increased temperature and decreased soil moisture will act to reduce global crop yields by 2050, the direct fertilization effect of rising carbon dioxide concentration ([CO2]) will offset these losses. The CO2 fertilization factors used in models to project future yields were derived from enclosure studies conducted approximately 20 years ago. Free-air concentration enrichment (FACE) technology has now facilitated large-scale trials of the major grain crops at elevated [CO2] under fully open-air field conditions. In those trials, elevated [CO2] enhanced yield by approximately 50% less than in enclosure studies. This casts serious doubt on projections that rising [CO2] will fully offset losses due to climate change.  相似文献   
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Forest liming is a common measure to counteract soil acidification. In forest practice, lime is applied to the forest floor where it changes the chemical properties. However, little is known about the depth impact of liming and the depth translocation of lime components. To investigate the long-term impact of forest liming, several study plots have been established in the 1980s in Germany in stands with different site conditions. We analysed soil chemical data obtained during the last 28?years from 45 of the study plots. We examined the depth impact of liming and predicted the main factors responsible for the increase in Calcium (Ca) and Magnesium (Mg) stocks after liming in the mineral soil using multiple linear regression analyses (MLR). Stocks of Ca and Mg as well as base saturation (BS) showed a strong depth gradient with significant differences between limed and control plots down to 40?cm of the mineral soil. About 65–70?% of applied Ca and Mg were recovered in the forest floor and the upper 40?cm of the mineral soil. BS in 0–40?cm increased by a mean of 11?%. MLR models could explain 48–74?% of the variation in mean changes of Ca and Mg in 0–10, 10–20 and 20–40?cm soil depth when soil and climate variables, amount of applied lime and years after liming are included in the model. After testing the model robustness with a cross-validating procedure, we concluded that these models might be applied to many regions in Central Europe with comparable soil and climate conditions and thus, have widespread application.  相似文献   
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