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101.
Thirty-two unimproved landraces of barley ( Hordeum vulgare L.) based on single plant selections in SE Finland were studied. Some of the lines still had ancient features, e.g., rachis brittleness in the tip of the spike. The lines showed 17 different and 16 unique hordein patterns and three lines showed more than one pattern, suggesting heterozygosity, and six different residual grain protein patterns. The three enzyme activities (-amylase, -amylase and -glucanase) of grains germinated aseptically for 120 h were determined. The average activity levels were high compared with a standard of five global barleys and with those determined previously in wild barley (H. vulgare ssp. spontaneum (Koch) Archers et Graebn.) grown in Finland. The ssp. spontaneum sample of 257 accessions showed significantly (P<0.001) less variation in -amylase and significantly (P<0.001) lower mean activity of all three enzymes. The high variation of these chemotypes indicates great potential variation of possible use by breeders has been lost by the disappearance and displacement of local barleys with commercial cultivars since 1950 in Finland before which barley cultivation and adaptation to the local environment had occurred over more than 3000 years. Selection for currently preferable plant characteristics in the descendants of the cross of HA52 (a landrace selection) × Adorra discriminated the hordein pattern of HA52 not being directly selected. The best landraces outyield the standard cultivars especially when there was no lodging. Top yield and small grains appeared to be associated characteristics under the environmental selection pressure, conflicting with the man-made regulations of the EU.  相似文献   
102.
We evaluated changes occurring in the rhizosphere microbial communities of Scots pine (Pinus sylvestris L.) due to tree-felling and decrease of the photosynthetic C flow into the soil under field conditions over one growing season. Samples were taken from tree rhizospheres, freshly felled stump rhizospheres and bulk soil. We used culture dependent (CFU counts, community level physiological profiles, CLPPs) and independent methods (fluorogenic MUF-substrates, PLFA pattern and PCR-DGGE) to monitor the microbial communities in soil samples. The numbers of cultivable bacteria and amounts of phosphatase activity in the rhizosphere of trees were significantly higher compared with those in the bulk soil. The organic C consuming community measured by CLPP was stimulated directly after the tree-felling in stump rhizospheres; utilization of the disintegration components of cellulose, hemicellulose and chitin increased. Furthermore, bacterial and fungal biomass as well as chitin decomposers (CFU) increased in the stump rhizosphere. After 11 weeks of tree-felling the stump rhizosphere soluble PO4-P and NH4-N as well as amounts of total C and N began to resemble the concentrations measured in the bulk soil. However, the stump rhizosphere community structure detected by PLFA and PCR-DGGE still resembled that of the tree rhizosphere.  相似文献   
103.
In an experiment with factorial design performed in a mature, mixed Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) stand in central Finland, we studied the effects of sod cutting (exposing the mineral soil simulating mechanical site preparation) and trenching the study plot (excluding root-mycorrhizal connections) on soil organisms, decomposition rate and pine seedling performance. During two growing seasons after sod cutting, the growth of pine seedlings was significantly enhanced compared to plots with the organic layer left intact. Some epiedaphic soil animals, such as ants, spiders and certain entomobryid collembolan, were more active (pitfall sampling) on sod-cut plots. By the end of the second growing season numbers of enchytraeids were greater in the exposed mineral soil than in the mineral soil under the forest floor. Trenching induced changes in microbial phospholipid fatty acid (PLFA) pattern and collembolan community structure with decreased numbers of collembolans and biomass of fungi in organic soil of uncut plots. In addition, N content of pine seedlings increased after trenching. Overall, the effects of trenching on the measured variables were similar in sod-cut and uncut plots. We conclude that the effects of mechanical site preparation on decomposers and decomposition processes can be explained partly by exclusion of mycorrhizal-root connections and partly by a decrease in unfavourable conditions created by the organic soil layer and ground vegetation.  相似文献   
104.
Abstract

The aim of the study was to investigate lesions in sows and their piglets kept on two flooring materials – bare concrete and concrete coated with polyurethane containing sand. In total, 13 lactations on concrete and 11 on polyurethane were evaluated. The severity of skin lesions was scored and teat and claw lesions were recorded. The sand-filled coating was rougher compared to the concrete floor. Larger litter sizes were associated with a higher proportion of wounded teats in sows. Only seven of the 230 piglets had no skin lesions. The piglet skin lesions generally healed, since the number of more severe lesions decreased (p<0.001) and the number of less severe lesions (p<0.001) increased over time. Piglet lesions were associated with daily weight gain and litter size. The number of skin lesions on sows and piglets did not differ between animals kept on concrete and polyurethane-covered flooring. However, piglets kept on the latter flooring had more frequent claw lesions. On both types of flooring the majority of the piglets had skin lesions. Piglets had more claw lesions on polyurethane coating due to its roughness. In addition to the possibility of lower weight gains in piglets due to severe lesions, pig skin lesions are themselves a severe welfare problem in this type of housing system.  相似文献   
105.
Prompted by developments in the agri-food industry and associated recent changes in European legislation, the responsibilities of veterinarians professionally active in veterinary public health (VPH), and particularly in food hygiene (FH), have increasingly shifted from the traditional end-product control toward longitudinally integrated safety assurance. This necessitates the restructuring of university training programs to provide starting competence in this area for veterinary graduates or a sub-population of them. To date, there are substantial differences in Europe in the way in which graduate programs in FH/VPH are structured and in the time allocated to this important curricular group of subjects. Having recognized this, the European Association of Establishments for Veterinary Education (EAEVE) recently instituted a working group to analyze the current situation, with a view to produce standard operating procedures allowing fair and transparent evaluations of universities/faculties constituting its membership and in concurrence with explicit European legislation on the professional qualifications deemed necessary for this veterinary discipline. This article summarizes the main conclusions and recommendations of the working group and seeks to contribute to the international efforts to optimize veterinary training in FH/VPH.  相似文献   
106.
The objective of the study was to examine the success of regeneration in gaps of variable size in pine-dominated stands in terms of seedling density. It was based on an experiment in central Lapland containing circular clear-cut gaps of 20, 40 and 80 m in diameter on typical sub-xeric and xeric pine sites with site preparation (patch scarification). The observation period covered the first five years after cutting. The average number of seedlings that had emerged after gap cutting was about 22 000?ha?1 for pine and 7 000?ha?1 for birch. The proportion of regeneration sample plots without any pine seedlings was less than 10%. The seedling density diminished constantly with greater distance from the edge stand but indicating sufficient density up to the largest gap size in the study (diameter 80 m, area ca. 0.5?ha). Site preparation promoted regeneration remarkably, and we conclude that successful regeneration would be achieved in most cases with soil scarification exposing just 10–20% of the soil surface.  相似文献   
107.
Glycemic responses to most of the conventional breads are high, including breads made of wholemeal flour. Baking technology is known to affect these responses. The aim of the present study was to investigate effects of xylanase enzyme treatment and sourdough fermentation in wholemeal wheat bread baking on postprandial glucose and insulin responses and on in vitro protein digestibility. The wheat breads were made of 100% flour from peeled kernels by a straight dough or sourdough fermentation method, and with or without using xylanase during mixing of dough. Standard white wheat bread was used as a reference. All test bread portions contained 50 g available carbohydrate and were served in random order to eleven insulin resistant subjects. Blood samples for measuring glucose and insulin concentrations were drawn over 4 h. The sourdough wholemeal wheat bread resulted in the lowest postprandial glucose and insulin responses among the four tested breads (treatment × time; p = 0.000 and p = 0.022, respectively). There were differences in solubility and depolymerisation of protein and arabinoxylan among the breads but these did not fully explain the in vivo findings. In conclusion, the health effects of wholemeal wheat bread can be further improved by using sourdough process in breadmaking.  相似文献   
108.

Background

Animal mycobacterioses are regarded as a potential zoonotic risk and cause economical losses world wide. M. avium subsp. hominissuis is a slow-growing subspecies found in mycobacterial infected humans and pigs and therefore rapid and discriminatory typing methods are needed for epidemiological studies. The genetic similarity of M. avium subsp. hominissuis from human and porcine origins using two different typing methods have not been studied earlier. The objective of this study was to compare the IS1245 RFLP pattern and MIRU-VNTR typing to study the genetic relatedness of M. avium strains isolated from slaughter pigs and humans in Finland with regard to public health aspects.

Methods

A novel PCR-based genotyping method, variable number tandem repeat (VNTR) typing of eight mycobacterial interspersed repetitive units (MIRUs), was evaluated for its ability to characterize Finnish Mycobacterium avium subsp. hominissuis strains isolated from pigs (n = 16) and humans (n = 13) and the results were compared with those obtained by the conventional IS1245 RFLP method.

Results

The MIRU-VNTR results showed a discriminatory index (DI) of 0,92 and the IS1245 RFLP resulted in DI 0,98. The combined DI for both methods was 0,98. The MIRU-VNTR test has the advantages of being simple, reproducible, non-subjective, which makes it suitable for large-scale screening of M. avium strains.

Conclusions

Both typing methods demonstrated a high degree of similarity between the strains of human and porcine origin. The parallel application of the methods adds epidemiological value to the comparison of the strains and their origins. The present approach and results support the hypothesis that there is a common source of M. avium subsp. hominissuis infection for pigs and humans or alternatively one species may be the infective source to the other.  相似文献   
109.
We studied the establishment of natural seedlings after seed tree cutting and scalping in two drained Scots pine peatland stands in northern Finland (Simo and Sievi). Approximately, 50?ha?1 of Scots pine stems were retained on both sites. During the six subsequent years, five seedling surveys were conducted. The effect of site preparation was analysed using generalized linear mixed models (GLMM). The mean density of pine seedlings increased more quickly in the scalped plots and was ca. 1.1?m?2 after six years compared to 0.87?m?2 in the non-scalped plots, on average. Scalping increased the number of pine seedlings 2-fold compared to that in non-treated plots in Simo, however, in Sievi non-treated plots had 30% higher pine seedling density after six years. Downy birch seedling density was 9–10-fold compared to that of non-treated plots in both sites. In terms of seedling density, seed tree cutting led to satisfactory pine regeneration after just two growing seasons in drained pine peatlands, even without scalping. Scalping significantly increased the number of pine seedlings, but it also enhanced the germination of birch seedlings strongly.  相似文献   
110.
In this work, empirical ring-based models were developed to predict the distribution of early wood percentage, wood density and fibre length along the stems of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) as affected by silvicultural management. The performance of the ring-based models was also compared for Scots pine and Norway spruce with corresponding disc-based (cross-sectional) models. Moreover, both models were integrated with example simulations by a process-based growth and yield model to analyze how management, such as thinning, affects the growth and wood properties of Scots pine trees over a rotation as an average for the tree stem, but also along the stem.The ring-based models built for annual early wood percentage (explained by ring width), air dry wood density (explained by early wood percentage and cambial age) and fibre length (explained by radial growth percentage and cambial age) predicted reasonably well the wood properties both at an intra-ring level, but also at a cross-sectional level. These predictions were also reasonably well in line with corresponding cross-sectional predictions by the disc-based models (which predicted the properties based on the number of annual rings and diameter at breast height and/or the cross-section being considered and temperature sum). The example simulations also demonstrated that both models predicted slightly lower wood density for dominant trees compared to dominated ones grown in thinned and unthinned Scots pine stands over a rotation. Unlike the disc-based model, the ring-based model predicted, on average, higher early wood percentage in dominant trees than in dominated ones. However, fibre length was not significantly affected when the averages of the whole stems were predicted, and this held true for both ring- and disc-based models.In summary, the incorporation of empirical ring-based wood property models into a process-based growth and yield model, offers a means to study in detail how environmental conditions, forest structure and management affect the quantity and properties of stem wood produced over a rotation. The disc-based wood property models used in this work are based on data with large geographical and genetic variation, and therefore may turn out to be more applicable for predicting future wood and fibre resources at a regional and national level. This kind of integrated use of wood property models with a process-based growth and yield model could help us to evaluate the forest resources under current and changing climate.  相似文献   
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