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1.
Introduction   总被引:1,自引:0,他引:1  
Pedroli  Bas  Harms  Bert 《Landscape Ecology》2002,17(1):1-12
The realization of strategies for sustainable land use assumes specificresearch concepts from the local to the global scale (micro-, meso- andmacroscale). Therefore, landscape ecological science has to provideinvestigation methods for all these different scales. By combiningtop-down and bottom-up approaches in addition tocoupled GIS-model applications and traditional methods, the investigation oflandscape ecological structures and processes seems to be possible. Thepresented studies show this approach on examples of two study areas in EasternGermany: A watershed of 400 km2 and an administrativedistrict of about 4000 km2. The scale-specificapplicability of several models and methods were tested for theseinvestigations, and the validation of the calculated results are presented. Animportant outcome of the project should be the prevention of conflicts betweenagriculture, water management and soil, and water and nature conservation;based onrecommendations for land use variants with decreased pollutant loading withinagricultural areas. The scale specific investigations can be considered as abase for establishing sustainable land use.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   
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A new method was developed to identify regions in proteins from which peptides are derived with specific functional properties. This method is applicable for systems in which peptides of a hydrolyzed protein possess specific functional properties, but are too large to be sequenced directly and/or the peptide mixture is too complex to purify and characterize each peptide individually. In the present work, aggregating peptides obtained by proteolytic hydrolysis of soy glycinin were used as a case study. The aggregating peptides are isolated and subsequently further degraded with trypsin to result in peptides with a mass <5000 Da to enable sequence identification using RP-HPLC-MS in combination with MS/MS. Prior to RP-HPLC the peptides are fractionated using anion and cation exchange chromatography. The fractions obtained are analyzed with RP-HPLC-MS. The peptides, with identified sequences, were quantified using the peak areas of the RP-HPLC chromatograms measured at 214 nm. Next, the peak areas were corrected for the molar extinction coefficient of the individual peptides, followed by accumulative-quantitative peptide mapping. The results show that in complex systems, based on the method described, the regions in the parental protein from which the functional peptides originate can be properly identified.  相似文献   
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Journal of Pest Science - In Peninsular Malaysia, barn owls (Tyto javanica javanica) have been utilized as biological control of rats since the 1960s. In this study, the impact of introduced barn...  相似文献   
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This research work reports new electrically conductive paper made of pineapple leaf fiber and polyaniline (PALF/PANI). The conductive paper shows remarkable preservation of mechanical properties while achieving its conductive state. Also it was found that, the amount of PANI needed to achieve the conductivity transformation is as low as 5 wt.%.  相似文献   
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Genetic Resources and Crop Evolution - Mangosteen (Garcinia mangostana var. mangostana) is an obligate apomictic species which does not require a fertilization process to produce seeds. The absence...  相似文献   
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The term bioeconomy and closely related notions like bio-based economy or knowledge-based bioeconomy (KBBE) are increasingly used by scientists and politicians in the last years. It does therefore have the potential of becoming an influential global discourse. Its role is however so far unclear. The general assumption that guides this paper is that discourses, resulting ideas and arguments are generally said to have performative power. They shape actors' views, influence their behaviour, impact on their beliefs and interests and can cause institutional change in a given society. Thus, the aim of this paper is twofold: first, it aims to analyse whether the ideas used in a bioeconomy discourse differs from those in other global meta-discourses of the last decades affecting forest discourses, such as the ecological modernization discourse or the sustainable development discourse. Second, this paper aims to analyse whether and how the bioeconomy discourse has started (or not) to reshape or overshadow the “classical” forest discourses, such as sustainable forest management, forest biodiversity or forest and climate change.  相似文献   
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Pharmacokinetics and bioavailability of enrofloxacin were determined after single intravenous (IV) and intramuscular (IM) administrations of 5 mg/kg body weight (BW) to 5 healthy adult Angora goats. Plasma enrofloxacin concentrations were measured by high performance liquid chromatography. Pharmacokinetics were best described by a 2-compartment open model. The elimination half-life and volume of distribution after IV and IM administrations were similar (t1/2beta, 4.0 to 4.7 h and Vd(ss),1.2 to 1.5 L/kg, respectively). Enrofloxacin was rapidly (t1/2a, 0.25 h) and almost completely absorbed (F, 90%) after IM administration. Mean plasma concentrations of enrofloxacin at 24 h after IV and IM administration (0.07 and 0.09 microg/mL, respectively) were higher than the minimal inhibitory concentration (MIC) values for most pathogens. In conclusion, once-daily IV and IM administration of enrofloxacin (5 mg/kg BW) in Angora goats may be useful in treatment of infectious diseases caused by sensitive pathogens.  相似文献   
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The objectives of this study were to assess how functional properties of proteins in whole meal wheat (Triticum aestivum L.) flour vary across different growth environments. Grain from three commercial Australian Hard milling wheat cultivars was analyzed from four growth locations in 2008 and from two of the corresponding cultivars and locations in 2009. The protein content of the grain, soluble and insoluble extractable protein fractions, swelling index of glutenin (SIG), glutenin‐to‐gliadin ratio (Glu:Gli), percent unextractable polymeric protein (%UPP), and dough properties including force at maximum resistance (Rmax) and extensibility were measured. Based on analysis of variance of aggregated data for the cultivars, growth locations, and seasons, growth environment factors made significant contributions to variability in the total grain protein, Glu:Gli ratio, %UPP, SIG, Rmax, and extensibility of the wheat flour. Variability of protein content of the soluble and insoluble extractable protein fractions was mostly owing to genotype.  相似文献   
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The effects of anabolic agents (5 mg of estradiol-17 beta + 30 mg of trenbolone acetate) on body characteristics and chemical composition of gain were studied in 58 intact male goat kids fed milk replacer. Four kids were slaughtered at 7 d of age to constitute the initial group. The other kids were allotted in a 2 x 3 factorial arrangement with slaughter age (41, 49, and 56 d of age) and treatment (control and implanted at 21 d old) as factors. Energy intake decreased during the first 4 wk after treatment; implanted kids had the same ADG as controls but a better energy efficiency (P < .05). During the last week of the trial, energy intake was the same; treated kids tended (P < .10) to have a higher empty body gain (EBG). Anabolic agents increased carcass (P < .10) and hide proportions (P < .01) in empty BW and in EBG for all groups (except for carcass at 56 d old). Anabolic agents reduced the contribution of adipose tissues (P < .05), empty digestive tract (P < .05), and other organs (P < .01) to EBG. At all slaughter ages, the chemical composition of carcass and hide wet tissues, all dissectible adipose tissues, and EBG were altered by treatment. In these tissues (except for mesenteric fat tissue), water content increased and lipid content decreased (P < .05), but these effects diminished with age. Expressed on a DM basis, the CP content of the treated carcasses was increased in all groups (P < .05). Implanting high doses of steroids altered nutrient partitioning, which reduced fat and increased water and protein in the body.  相似文献   
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