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61.
Dipladenia sanderi Hemsl. ‘Rosea’ (syn.: Mandevilla sanderi (Hemsl.) Woodson ‘Rosea’) was grown in a glasshouse at 12, 15, 18 and 21°C, daylengths of 8 or 20 h, natural daylight, and natural daylight supplemented with cool-white fluorescent lamps (10 W m?2).Time from propagation to unfolded flower decreased with increasing temperature, and at 12°C there were relatively few flowers in the inflorescences. The time to flower opening was not influenced by daylength, but with 20 h there were more buds in the first developed inflorescence and the petals were larger than with 8 h. In addition, the vegetative growth was favoured by 20 h. Supplementary lighting shortened the developmental time to unfolded flower, but the flowers were smaller than in natural light only.The growth and development varied according to the time of year. Dipladenia was able to bloom all year round, except in January and February. The low light intensity in November and December probably made it impossible for the buds to develop into flowers in January and February.  相似文献   
62.
This study comprised the results of three different seawater trials using unique combination of techniques to study protease digestive efficiency and growth performance quality to illustrate the effects of light regimes and vaccine types in Atlantic salmon (Salmo salar L.). Fish with higher growth had higher trypsin (T) and chymotrypsin (C) specific activities with higher T/C ratio or slope T/C ratio [calculated from the regression between trypsin (y) and chymotrypsin (x) specific activities] in the pyloric caeca. The T/C ratios indicated fish growth rates over a period of 1–2 months, while the slope T/C ratios indicated fish growth rates at sampling. Adaptation period for adjustment to the new environment of continuous light was 70 days, indicated by the differences in trypsin specific activities and the crossing of slope T/C ratio regressions following with the changes in growth rate directions between the control and the treated group. Vaccine types affected fish vertebral growth, and additional continuous light enhanced the impact of vaccines on fish growth during springtime, indicated by differences in slope T/C ratios. Continuous light stimulated fish growth during winter to spring, when the natural day length was short, without significantly changing white muscle and oocyte qualities in the fish of about 500 g, except for significantly increased white muscle RNA concentration. Continuous light also reduced fish growth rate later during summer, when the natural day length was long, by precedently decreasing the T/C ratio in late spring. Interestingly, plasma levels of free lysine related to tryptic digestion were correlated with trypsin specific activity levels. Continuous light caused higher levels of most free amino acids (FAA) involved in nitrogen metabolism, higher incorporation of essential FAA for protein synthesis, and higher protein turnover rate (free hydroxyproline levels) in both plasma and white muscle. However, continuous light did not affect higher protein content, intracellular buffering capacity and RNA levels in the white muscle of the fish of about 1 kg, probably due to limitation of FAA available for protein synthesis. It is therefore suggested that enhancing fish growth by continuous light stimulation should be accompanied by increasing availability or content of dietary protein (and probably minerals), which in turn would improve the quality of fish growth performance through increasing fillet protein concentration, strengthening vertebral growth, and delaying oocyte development.  相似文献   
63.
Values and beliefs regarding communityfood security were investigated among participants in2–3 day participatory planning events related to thelocal food system in six rural counties from oneregion of upstate New York. The results of Qmethodology reveal three distinct viewpoints: a) theSocial Justice viewpoint, which is primarily concernedwith hunger and the potential harm caused by welfarereform; b) the Pragmatist viewpoint, which values thecontributions agriculture makes to local communitiesand is not concerned about environmental or socialexternalities of the dominant food system; and c) theVisionary viewpoint, which also values agriculture inthe community but is very concerned aboutenvironmental and social externalities. After theplanning events, the Pragmatist viewpoint experiencedan 88% increase in members and the other twoviewpoints became less salient. Various categories ofprofessionals (e.g., nutrition, social welfare,agriculture, environmental) tend to express theviewpoints associated with their professions and/orthe client groups they serve. Despite thesedifferences among participants, the planning events inall six counties resulted in a wide range of goals andobjectives centered on a theme of re-localizing avariety of food system activities. These results arediscussed in relation to the desirability ofdeveloping an explicit philosophy of food andagriculture and the ideal processes required to doso.  相似文献   
64.
Low molecular mass organic acids (LMMOAs) and hydroxamate siderophores (HS) are molecules secreted by microbes and have previously been found in soil solution and in cultures. Mycorrhizal fungi are suggested to be involved in the nutrient uptake processes of trees and weathering of minerals. In this study soil samples taken from the O and E horizons of a podzol were extracted with 10 mM potassium phosphate buffer at pH 7.2. Variable parameters included addition of methanol to the extraction buffer and the use of ultrasonication or rotary shaking during extraction. LMMOAs and HS content of the soil extracts were determined. Analysis of soil extracts were carried out by liquid chromatography mass spectrometry (LC–MS) and the extraction results compared to results for soil solution samples obtained by centrifugation of the soils sampled. The extraction yields were significantly increased by addition of methanol to the extraction buffer, especially for the O horizon samples. Rotary shaking of the samples for 90 min gave slightly higher yields than ultrasonication for 15 min but the reduction in extraction time makes ultrasonication an attractive option. Of the HSs determined, ferricrocin was found in all samples. Optimal extraction conditions showed citric acid and isocitric acid to be the most abundant organic acids in the O and E horizons, respectively.  相似文献   
65.
Plasma growth hormone (GH), insulin-like growth factor-I (IGF-I), and insulin were measured in two groups of Salmo salar L. during a one-year study. The fish were reared under either a simulated natural photoperiod (SNP) from January to December or a regime of continuous light from January to June, followed by SNP until December (LL/SNP). Plasma GH levels during spring were low, and lower in the LL/SNP fish (< 0.9 ng ml− 1) than in the SNP fish (> 1.9 ng ml− 1), although the LL/SNP grew better (0.8% per day) than the SNP fish (0.5% per day). Plasma IGF-I levels increased transiently from January (64.7 ng ml− 1) to maximum in late September in the LL/SNP (85.8 ng ml− 1) and in November in the SNP group (87.3 ng ml− 1). The ratio GH:IGF-I was lower in the LL/SNP group during spring when this group grew better than the SNP group.  相似文献   
66.
This study investigated the individual variation in vertebral morphology and mineral content (as % of bone dry weight) in rapid growing underyearling smolt (n = 33) twelve weeks after transfer to seawater. The smolt, which were reared in triplicate tanks, had a large individual variation in vertebral bone mineral content (Tank A: 36.2% min, 45.2% max, 39.6% mean. Tank B: 32.6% min, 46.6% max, 40.0% mean. Tank C: 38.5% min, 47.9% max, 42.4% mean), and were subdivided into two groups based on mean within each tank: high mineral content (HMC, above tank mean, n = 15) and low mineral content (LMC, below tank mean, n = 18). Vertebrae of smolt with a low mineral content were more compressed in the anterior–posterior direction (HMC vertebral length/dorso-ventral diameter ratio 0.83, LMC 0.80). This was related to a change in the growth direction of the vertebral cone. This change occurred around transfer to seawater and was characterised by an increased angle between the wall of the cone of the vertebrae and the cranial–caudal axis, and gave the vertebrae a compressed appearance. Smolt with a high mineral content were significantly longer (HMC 28.1 cm, LMC 26.5 cm) and heavier (HMC 270 g, LMC 210 g) twelve weeks after transfer to seawater.  相似文献   
67.
Due to increased whole-tree harvesting in Swedish forestry, concern has been raised that a depletion of nutrients in forest soil will arise. The Swedish Forest Agency recommends compensation fertilization with wood ash to ensure that unwanted effects are avoided in the nutrient balance of the forest soil and in the quality of surface water. In this investigation, the chemistry of two first-order streams, of which one was subjected to a catchment scale treatment with 3 tonnes of self-hardened wood ash/ha in the fall of 2004, was monitored during 2003?C2006. Large seasonal variations in stream water chemistry made changes due to ash application difficult to detect, but evaluating the ash treatment effects through comparison of the stream water of the treated catchment with the reference was possible via statistical tools such as randomized intervention analysis in combination with cumulative sum charts. The wood ash application did not yield any significant effect on the pH in the stream water and hence did not affect the bicarbonate system. However, dissolved organic carbon increased, a previously unreported effect of WAA, bringing about an increase of organic anions in the stream water. The wood ash application also induced significant increases for Ca, Mg, K, Si, Cl and malonate, of which K was most prominent. Although significant, the changes induced by the wood ash application were all small compared to the seasonal variations. As a tool to counteract acidification of surface waters, WAA seems to have limited initial effects.  相似文献   
68.
Effects of a Trichoderma reesei tyrosinase (TYR) and a Trametes hirsuta laccase (LAC) on breadmaking performance of gluten-free oat flour were investigated by SDS-PAGE analysis of oat protein fractions, large deformation rheology, and microscopy of the doughs, as well as on the basis of specific volume and firmness of the gluten-free breads. TYR induced the formation of higher molecular weight proteins in the SDS-PAGE assay. Microscopical analysis showed more intensive protein aggregation in the TYR-treated dough than in the dough without TYR. TYR also increased the firmness of the dough, which was assumed to be because of the cross-linking of oat globulins. LAC did not affect the oat globulins. TYR alone, or together with a commercial Thermomyces lanuginosus xylanase (XYL), increased significantly the specific volume of the gluten-free oat bread. A combination of TYR and XYL also increased the softness of the bread, whereas a combination of LAC and XYL improved the specific volume but did not affect the softness of oat bread. The results thus indicate that cross-linking of oat globulins by TYR, especially with the addition of XYL, was beneficial for improving the texture of gluten-free oat bread.  相似文献   
69.
70.
Several studies have shown that healthy individuals with fasting plasma glucose (FPG) levels at the high end of the normal range have an increased risk of mortality. To identify genetic determinants that contribute to interindividual variation in FPG, we tested 392,935 single-nucleotide polymorphisms (SNPs) in 654 normoglycemic participants for association with FPG, and we replicated the most strongly associated SNP (rs560887, P = 4 x 10(-7)) in 9353 participants. SNP rs560887 maps to intron 3 of the G6PC2 gene, which encodes glucose-6-phosphatase catalytic subunit-related protein (also known as IGRP), a protein selectively expressed in pancreatic islets. This SNP was associated with FPG (linear regression coefficient beta = -0.06 millimoles per liter per A allele, combined P = 4 x 10(-23)) and with pancreatic beta cell function (Homa-B model, combined P = 3 x 10(-13)) in three populations; however, it was not associated with type 2 diabetes risk. We speculate that G6PC2 regulates FPG by modulating the set point for glucose-stimulated insulin secretion in pancreatic beta cells.  相似文献   
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