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1.
Acrylamide exposure was investigated in subgroups of the EPIC study population (510 subjects from 9 European countries, randomly selected and stratified by age, gender, and smoking status) using hemoglobin adducts of acrylamide (HbAA) and its primary metabolite glycidamide (HbGA). Blood samples were analyzed for HbAA and HbGA by HPLC/MS/MS. Statistical models for HbAA and HbGA were developed including body mass index (BMI), educational level, and physical activity. A large variability in acrylamide exposure and metabolism between individuals and country groups was observed with HbAA and HbGA values ranging between 15-623 and 8-377 pmol/g of Hb, respectively. Both adducts differed significantly by country, sex, and smoking status. HbGA values were significantly lower in high alcohol consumers than in moderate consumers. With increasing BMI, HbGA in nonsmokers and HbAA in smokers decreased significantly. In the assessment of potential health effects related to acrylamide exposure, country of origin, BMI, alcohol consumption, sex, and smoking status should be considered.  相似文献   
2.
Growth and carcass quality of European rainbow trout populations were compared in a full sib family test over five experimental periods. In total, 131 full-sib families of 17 different populations, (i.e. 19 500 fish), were included. A special system for family testing in trout was developed. This consisted of separate hatching of single pair matings, separate rearing of families up to marketable size and common fattening under two stocking densities. Thus, growth was studied separately for the rearing and the fattening period. The observed differences in rearing and fattening weight between and within populations were quite distinct and of significance for production and breeding efficiency. Similar ranking of populations after fattening in different years and under different stocking densities indicated that the final weight was highly genetically controlled. Carcass characteristics determined at marketable size showed somewhat smaller differences between populations. Populations with the highest fattening weight did not generally produce the most valuable carcasses. The results are discussed with respect to their impact on breeding strategies.  相似文献   
3.
The objective of the joint project between the two universities of Bonn and Sarajevo was to study the effects of climate change associated with warmer winter and spring temperatures on fruit tree phenology. Changes in flowering date of apple and cherry were correlated with local weather data obtained concomitantly on-site at four locations in the Balkan countries Slovenia, Serbia, B & H and at Bonn, Germany.Phenological data of flower opening (F1; BBCH 61) of apple cv. ‘Golden Delicious’ originated from 55 years at Cacak (44?°N, Serbia) and at Klein-Altendorf, University of Bonn (50?°N), cv. ‘Bobovec’ from the University of Ljubljana (46?°N, Slovenia) and cherry cv. ‘Burlat’ (35 years at Klein-Altendorf, 50?°N) and 20–30 years at Tuzla (44?°N, B & H) and Mostar (43?°N, Bosnia & Herzegovina; B & H).The annual precipitation showed a negligible change in the last 55 years of ±5% in the Balkan countries (e.?g. Cacak, 699?mm), but only ±1.8% at Klein-Altendorf (605?mm) with a slight shift to more winter rainfall.Regression analysis showed an increase in mean temperature of 1.7?°C (annual) and 1.45?°C for the vegetation period at Klein-Altendorf (last 55 years), Germany. In the evaluated Balkan stations, the greatest increase in annual air temperature between two climate phases (until 1987 versus from 1988 until now) was at Ljubljana (1.4?°C) and Cacak (1.2?°C) in contrast to the least increase (0.3?°C) at Tuzla (annual average 10?°C) and an intermediate value (0.9?°C) in the warmer Mostar (annual average 14.5?°C).This recent temperature increase advanced flower opening by 10–14 days for apple such as cv. ‘Golden Delicious’ at Cacak and 7–10 days (last 55 years) at Bonn and 4–5 days (last 35 years) for the early cherry cv. ‘Burlat’ at Klein-Altendorf/Bonn; at Mostar and Tuzla, the effect of climate change was greater with the early cherry cv. ‘Burlat’ (26 days) compared with the difference of the late cherry cultivar (16 days). Before recent climate change (1973–1987), cherry flower was advanced by 10 days in the warmer med climate at Mostar but delayed by 16 days in the cooler Tuzla. The results, i.?e. the flower advancement in the Continental climate but flower delay in the med climate, are discussed with respect to the risk of late frost and countermeasures to combat climate change effects.  相似文献   
4.
Leonelli S 《Science (New York, N.Y.)》2010,330(6002):317; author reply 318-317; author reply 320
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5.
The inhibitory effect of the herbicide diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] on microbial activity in red Latosol soil was followed using microcalorimetry. The activity of the micro-organisms in 1.50 g of soil sample was stimulated by addition of 6.0 mg of glucose and 6.0 mg of ammonium sulfate under 35% controlled humidity at 298.15 (+/- 0.02) K. This activity was determined by power-time curves that were recorded for increasing amounts of diuron, varying from zero to 333.33 micrograms g-1 soil. An increase in the amount of diuron in soil caused a decrease of the original thermal effect, to reach a null value above 333.33 micrograms g-1 of herbicide. The power-time curve showed that the lag-phase period and peak time increased with added herbicide. The decrease of the thermal effect evolved by micro-organisms and the increase of the lag-phase period are associated with the death of microbial populations caused by diuron, which strongly affects soil microbial communities.  相似文献   
6.
Biodegradability of chlorhexidine (CH), triclosan (TC), and benzalkonium chloride (CBA) has been tested in 18 surface water sampling points in the urban area of Buenos Aires. Sampling points were located in both the Reconquista and the Matanza-Riachuelo basins as well as in the La Plata River. High tolerance to the three disinfectants was found and indigenous strains capable of degrading CBA and TC were isolated. Neither tolerance nor biodegradation were correlated with sewage pollution. A strain that degrades CBA was identified as belonging to the genus Pseudomonas using the API20NE system and 16SRNA sequencing. In batch assays, the strain was capable of degrading 100, 200, and up to 500 mg L?1 of CBA in 10, 25, and 46 h respectively with specific growth rates (μ) of 0.56, 0.30, and 0.14 h?1. The efficiency of the process was between 99.5–98.0% in terms of compound removal and between 93.8–89.1% in terms of chemical oxygen demand (COD). The detoxification of the compound as a result of the biodegradation was assessed using Pseudokirchneriella subcapitata, Vibrio fischeri, and Lactuca sativa as test organisms.  相似文献   
7.
The soil fungal diversity and community partitioning between the bulk soil and stone compartments was investigated using PCR based approaches targeting the barcoding internal transcribed spacer (ITS) of rDNA and the laccase encoding functional gene as genetic markers. Soil samples were collected from the B-horizon of spruce and beech forests at the Hainich Biodiversity Exploratory, central Germany. The targeted markers were amplified from the respective DNA extracts using general fungal primers and basidiomycete laccase gene specific primers, cloned and sequenced. Differences in the fungal community composition between the two forest types and the soil compartments were indicated by both markers. When the effects of ecological factors were considered, the two markers produced different patterns of results. The ITS rDNA marker revealed communities principally influenced by forest type, while those detected with the functional marker were mainly affected by soil pH. The fungal communities detected by the functional marker in particular, differed significantly between soils and stones, indicating that laccase-producing fungi are specifically adapted to degrade organic matter in soils rather than weathering of stones. The study underlines the fact that coherent and complementary results may be obtained with both genetic markers used.  相似文献   
8.
9.
To improve phosphorus (P) fertilization and environmental assessments, a better understanding of release kinetics of solid-phase P to soil solution is needed. In this study, Fe (hydr)oxide-coated filter papers (Fh papers), isotopic exchange kinetics (IEK) and chemical extractions were used to assess the sizes of fast and slowly desorbing P pools in the soils of six long-term Swedish field experiments. The P desorption data from the Fh-paper extraction of soil (20 days of continual P removal) were fitted with the Lookman two-compartment desorption model, which estimates the pools of fast (Q1) and slowly (Q2) desorbing P, and their desorption rates k1 and k2. The amounts of isotope-exchangeable P (E) were calculated (E1min to E>3 months) and compared with Q1 and Q2. The strongest relationship was found between E1 min and Q1 (r2 = .87, p < .01). There was also an inverse relationship between the IEK parameter n (the rate of exchange) and k1 (r2 = .52, p < .01) and k2 (r2 = .52, p < .01), suggesting that a soil with a high value of n desorbs less P per time unit. The relationships between these results show that they deliver similar information, but both methods are hard to implement in routine analysis. However, Olsen-extractable P was similar in magnitude to Q1 (P-Olsen = 1.1 × Q1 + 2.3, r2 = .96), n and k1 were related to P-Olsen/P-CaCl2, while k2 was related to P-oxalate/P-Olsen. Therefore, these extractions can be used to estimate the sizes and desorption rates of the different P pools, which could be important for assessments of plant availability and leaching.  相似文献   
10.
Based on data from the National Lynx Census, carried out in Poland in 2000-2001, and using Geographic Information System, we analysed nine habitat characteristics in 56 circular sample plots (113 km2 each), where lynx (Lynx lynx) have been recorded, and 118 plots with no signs of their presence. In plots with lynx the forest cover (on average 68%) was two times higher and the forest fragmentation lower than in plots with no lynx records. The plots with and without lynx differed significantly also in the number of villages and towns, length of main motorways and railways. Lynx occurrence was negatively associated to human settlements and transportation infrastructure. Logistic regression analysis showed that sufficient forest cover (>40%) and the short straight-line distance to the eastern or southern border of Poland (as a proxy of the distance to a more contiguous range of lynx in Europe) are the two most important variables explaining lynx distribution. We conclude that, in Poland, increase of forest fragmentation and transportation infrastructure may become important threats to lynx populations.  相似文献   
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