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181.
The enzyme rhodanese (EC 2.8.1.1) is an ubiquitous enzyme which is present in all living organisms, from bacteria to man. It is speculated that this enzyme plays a central role in cyanide detoxification. However, its wide tissue distribution suggests this enzyme might perform other functions beside cyanide detoxification. Although the distribution of rhodanese in different tissues of human and domestic animals has been studied, little is known about the pattern of distribution and physiological roles of this enzyme in the cat. The purpose of this investigation was to determine the enzyme levels and compare the distribution of this enzyme in different tissues of the cat. A selection of tissue samples was assayed for rhodanese activity. The protein content of tissue extracts and enzymatic activities were calculated as units per gram tissue and units per milligram protein of the tissue. Results showed that in terms of units per milligram protein of the tissue (specific activity of the enzyme), colon and rectum mucosal layers and testis were the richest sources of the enzyme followed by ovary, mucosal layer of jejunum and liver. With respect to units/gram tissue, liver followed by testis, colon and rectum mucosal layers, ovary and mucosa of jejunum exhibited highest activities. The results of this study will allow one to speculate on the involvement of rhodanese in several biochemical and physiological functions in different tissues and organs of this species.  相似文献   
182.
Treatment of AIDS (HIV) and hepatitis C virus needs protease inhibitors (PI) to prevent viral replication. Uses of PI in therapy are usually associated with a decrease in body weight and dyslipidemia. Acylation stimulating protein (ASP) is a protein synthesized in adipocytes to increase triglycerides biosynthesis, for that the relation of PI and ASP to adipogenesis is tested in this work. ASP expression was increased during 3T3-L1 differentiation and reached a peak at day 8 with cell maturation. Addition of PI during adipocytes differentiation dose dependently and significantly (p < 0.5) inhibited the degree of triglycerides (TG) accumulation. Moreover, presence of ASP (450 ng/mL) in media significantly (p < 0.5) stimulated the degree of TG accumulation and there was additive stimulation for ASP when added with insulin (10 µg/mL). Finally, when ASP in different doses (Low, 16.7; Medium, 45 and High, 450 ng/mL) incubated with a dose of ×150 PI, ASP partially inhibited the PI-inhibited adipogenesis and TG accumulation. The results in this study show that PI inhibit lipids accumulation and confirm role of ASP in TG biosynthesis and adipogenesis.  相似文献   
183.
184.
The effect of brassinosteroids (BRs) was tested, in order to assess the possibility of alleviation of the adverse effects of high temperature stress on snap bean plants during delayed summer cultivation. Therefore, two field experiments were carried out in successive seasons, 2010 and 2011, with two bean cultivars ‘Paulesta’ and ‘Oxzira’, spraying with BRs of the following concentrations 0 (control), 25, 50 and 100 ppm. Plant growth, yield and pods quality of beans were studied. Spraying bean plants with BRs at a concentration of 25 and 50 ppm increased vegetative growth, total yield and quality of pods with no significant difference between both treatments. Using BRs at 25 ppm increased the total free amino acids (FAA) in leaves and total phenolic acids in the pod in comparison to control-treatment. ‘Oxzira’ cultivar resulted in the highest number of leaves, number of branches, dry weight of whole plant, total yield, total FAA in leaves and total phenolic acids in pod. Whereas, ‘Paulesta’ cultivar had the highest of plant length and total FAA in pods.  相似文献   
185.
The Government of Egypt is mandated toplan, construct, operate, manage, andmaintain the water system. However, withthe growing water demands over supplies inthe country, water management became a verydifficult task. This has led Egypt toreform policies, technologies,institutions, and development strategies tomanage water more effectively. One of thesestrategies is the irrigation managementtransfer (IMT) that has been a majorstrategy adopted to encourage farmers toplay a more important role in irrigationmanagement and related water services andalso share the cost of O&M of irrigationand drainage systems. IMT policy islaunched in Egypt as a pilot phase toexpand water users' participation atsecondary levels of the irrigation anddrainage systems. Four pilot areas (5,000–8,000 acre) representing all categories andgeographical locations of agriculturallands of Egypt were selected to implementthis policy.This study was conducted in these pilotareas prior to the start of any IMTactivities to describe, analyze, andexplain farmers' attitudes towardirrigation maintenance and implementationof IMT process. Socio-economicquestionnaires were designed and used asthe main tool for data collection. Afterthe field pre-test of the surveyinstrument, a sample of 240 farmers, 60from each pilot area, was selected usingthe sampling frame of multi-tiered process,and the statistical data analysis was doneusing SpssWin software.The major result of this study is that,without proper education and interface withfarmers, there is widespread resistance tothe idea farmers assuming management andmaintenance responsibilities beyond theon-farm level. It would have to proceedvery cautiously, and yield responsiveresults if it were to survive in the faceof the attitudes the farmers have shown,with their strong belief in the necessityof the role of the government. Meanwhile,farmers expressed great confidence in theIMT process and its objectives.  相似文献   
186.
The steady-state drainage equation ofHooghoudt (1940) has adrawback that tables for the determination of the so-calledequivalentlayer, de are needed. These calculations arecumbersome as de is dependenton the unknown spacing. Moreover, additional head islost due to theconvergence of stream lines towards the finite numberof perforations withinthe pipe wall. Therefore, corrections are required byreplacing the actualdrain radius by its effective radius. The designers inEgypt assume that thedepth of impermeable layer is infinity which resultsin an over estimationof drain spacing that will affect the ability of thedrainage system.Van der Molen and Wesseling (1991) have developed aseries solution toreplace the Hooghoudts approximation method for theequivalent depth by anexact solution. A comparison between this solution andthose of Lovell andYoungs (1984) and Hooghoudt (1940) showed that theexact solution proved tobe very accurate and efficient solution. The mainobjective of this study isto verify an accurate depth of the impermeable barrierand an effectiveradius of drain pipes which should be used in thedesign process using theexact solution.A field investigation was conducted in a study area of33,138 ha in theNorthern Delta of Egypt within Daqahliya Governorate.The results indicatethat a 5 m depth instead of infinity for theimpermeable layer in Nile Deltaand an effective radius of 90 mm should be used in thedesign process. Theuse of the exact solution for equivalent depth is acrucial issue especiallywith the high rate of on-going drainage projects inEgypt.  相似文献   
187.
Phytoextraction is a remediation technology that uses plants to remove heavy metals from soil. The success of a phytoextraction process depends on adequate plant yield (aerial parts) and high metal concentrations in plant shoots. A pot experiment was conducted to investigate the combination effects of plants [sunflower (Helianthus annuus) and canola (Brassica napus)] with soil treatments (manure, sulfuric acid and DTPA). Treatments, including two plants and seven soil treatments, which applied according to completely randomized factorial design with three replications. The largest shoot dry weight biomass production occurred in manure treatments for both plants. The maximum shoot concentrations of Pb and Zn were 234.6 and 1364.4 mg kg?1 respectively in three mmoles DTPA kg?1 treatment of sunflower. Furthermore the results showed that sunflower had a higher extracting potential for removal of Pb and Zn from polluted soil.  相似文献   
188.
The application of urea phosphate, urea nitrate and thoiurea to a silty clay soil from Nile Delta (pH 7.4, 1,9% CaCO3) inhibited soil urease activity if compared to urea. The nitrification process of ammonia formed from urea hydrolysis was retarded. The use of these urea derivatives eliminated nitrite accumulation and greatly retarded nitrate formation with increased recovery of urea-N throughout the experimental period. Gaseous losses of urea-N as ammonia or by denitrification were reduced. These derivatives may be much more advantageous than urea if fertilizer effeciency is to be increased.  相似文献   
189.
Soy isoflavones have been associated with several beneficial effects of soy in human diets. However, most soy is consumed by livestock in the Western countries. It is possible that isoflavones could be transferred and/or accumulated into animal products, which could become additional sources of dietary isoflavones for humans. Our objectives were to determine whether dietary isoflavone genistein could be transferred and/or accumulated into the eggs of Japanese quail (Coturnix japonica) and how the supplementation dosage and glycosylation of the isoflavone would affect this transfer. Adult reproductive female Japanese quail were randomly assigned to treatment groups that received encapsulated 50 or 100 mg genistein or 80 mg genistin per day (four quail per treatment) for 5 days. A control group (two quail) received placebo capsules. Eggs were collected prior to treatment and then daily for 15 days. The egg, separated into yolk and white, and pulverized quail diet were extracted in 80% methanol for 2 h and either centrifuged or filtered before evaporation of the solvent. The extracts were redissolved in 16% acetonitrile for high-performance liquid chromatography (HPLC) analyses. Genistein and genistein metabolites were detected in the egg yolks of treated quail. Trace concentrations of genistein were detected in the control group, due to the presence of genistein derivatives in the diet. Neither genistein nor its metabolites were found in egg white. Levels of genistein in the eggs increased significantly from the 3rd day of supplementation and reached the maximum about 2 days after the supplementation stopped. The higher dose of genistein supplementation resulted in higher genistein concentrations in egg yolks. Glycosylation decreased the transfer and accumulation of genistein into the egg yolks.  相似文献   
190.
The brain is the most essential part of the central nervous system which regulates and coordinates all body activities. Based on its phylogenetic development from the neural tube, the brain is divided into rhombencephalon (hindbrain), mesencephalon (midbrain) and prosencephalon (forebrain). The present study is achieved to describe the morphological characteristics of the normal forebrain in the donkey using the matched magnetic resonance imaging (MRI) and cross-sectional anatomy. Ten cadaveric heads of healthy adult donkeys of both sexes were used. Two heads were examined using a 1.5 Tesla MRI scanner, and the brains of the other heads were gently extracted; six brains were sectioned into transverse, dorsal and sagittal slices, and two brains were grossly inspected. MR images were selected in correlation to their closely corresponding gross sections. Both cross-sectional anatomy and MRI scans showed extensive gyration of the neocortex. The forebrain structures appeared with variable intensities on three sequences, Flair, T1-weighted and T2-weighted MRI, enabling comprehensive evaluation of the relevant neuroanatomical structures. The present study provided a precise neuroanatomical atlas of the forebrain in the donkey which could help in the quick and efficient interpretation of clinical diseases of the forebrain, localization of the forebrain functions and evolutionary neurobiology.  相似文献   
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