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1.
This paper introduces the vectorial Kappa (κv) that one can utilize to assess congruence between two vectorial mosaics. The vectorial Kappa extends for vectorial mosaics the approach of the so-called Cohen's Kappa index, commonly used to compare raster mosaics. By comparing both approaches, we aim to demonstrate how efficient and convenient a vector-based congruence may be when working on vectorial mosaics.  相似文献   
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U. Kutschera 《Planta》1991,184(1):61-66
The relationship between growth, change in cell osmotic pressure and accumulation of osmotic solutes was investigated in hypocotyls of sunflower (Helianthus annum L.) seedlings. During growth in darkness the osmotic pressure decreased by 50% between days 2 and 6 after sowing. After irradiation of dark-grown seedlings with continuous white light (WL) an inhibition of hypocotyl growth was measured, but the osmotic pressure of the growing cells was not lower than in the dark-grown control. Growth in darkness and after WL irradiation was accompanied by an increase in the amount of osmotic substances (soluble sugars) which was proportional to the increase in length of the organ. During growth in continuous WL the cell osmotic pressure decreased by 45 % between days 2 and 6 after sowing. The transfer of WL-grown seedlings to darkness (“re-etiolation”) resulted in a rapid acceleration of hypocotyl growth, but the cell osmotic pressure was the same as that of the WL grown control. Growth in continuous WL was accompanied by a corresponding accumulation of osmotic substances (soluble sugars). The transition from WL to darkness resulted in an enhanced accumulation of osmotica and an increase in cell-wall extensibility. The results indicate that the relative maintenance of cell osmotic pressure during rapid hypocotyl growth in darkness is caused by an enhanced accumulation of soluble sugars into the growing cells of the organ.  相似文献   
4.
Abstract The gene-protein database was used to obtain the two-dimensional polyacrylamide gel coordinates of proteins phosphorylated in extracts of Escherichia coli including those phosphorylated by eukaryotic-like kinase activities. These suggest that the phosphoproteins correspond to, or co-migrate with, the product of an open reading frame at 1.3 min (Orf80), Enzyme 1 of the phosphoenolpyruvate-dependent phosphotransferase system (Ptsl), the tRNA synthetase for histidine (HisS), and proteins involved in the response to carbon starvation and quinone treatment.  相似文献   
5.
From a literature review of five wildlife ecology journals since 1937, we document how using indices to monitor ungulate body condition is common practice, with the kidney fat index (KFI = weight of fat around the kidneys/weight of kidneys without fat × 100) as the favoured tool (82% of studies). In this context, we highlight the problems of using indices when underlying statistical assumptions are not met (isometry, parallel slopes between treatments). We show, with real and simulated data for two cervids with contrasting fat storage strategies, how results from analysis of variance of KFI values differ from analysis of covariance (ANCOVA) of raw data. We conclude that the KFI is affected by the restrictions typically associated with derived index values, and as a consequence, statistical analysis of the KFI could generate spurious results leading to erroneous interpretations concerning variation in body condition of ungulate populations. Thus, we recommend analysing fat weight as an untransformed variable in ANCOVA (kidney weight as covariate) to describe body condition variation in ungulates. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
6.
Coronary Artery Disease (CAD) is a major killer disease throughout the world. Dyslipidemia is a major contributor to the risk of CAD. Several dietary articles traditionally used in India and other South Asian countries reduced dyslipidemia. The present study was undertaken to evaluate the combined effect of Mung bean (Vigna radiata) and Elephant foot yam (Amorphophallus paeoniifolius) on serum lipids and atherogenic indices in albino rats and to compare it with a standard drug Cholestyramine. Thirty healthy albino rats of both sexes (150–200 g) were randomized to 5 groups of 6 animals each. The grouping were done based on the following criteria: Group I: Normal Control Group, Group II: (Standard Group): Cholestyramine resin 5 mg/kg bw, Group III: (Half Dose Group): Drug powder at 540 mg/kg bw, Group IV: (Effective Dose Group): Drug powder at 1080 mg/kg bw, and Group V: (Double Dose Group): Drug powder at 2160 mg/kg bw. Lipid profile was estimated at the beginning and after 30 days of treatment. The Effective and Double doses of the drug reduced Total cholesterol along with levels of Triglycerides, Low density lipoprotein and Very low density lipoprotein levels significantly (p < 0.01) along with a significant (p < 0.01) increase in high density lipoproteins (HDL) in rats. There was also significant (p < 0.01) improvement in atherogenic indices like Castelli Risk Index I, Non HDL C/HDL, Castelli risk Index II, TG/HDL, Atherogenic coefficient and Atherogenic Index of Plasma. The combination of powdered sprouted mung bean and yam powder have excellent lipid lowering potential.  相似文献   
7.
Major knowledge gaps exist with respect to light-quality regimes in the coastal-zone Strandzha Quercus frainetto (Q.f.) forest region adjoining the southern Bulgarian Black Sea. This paper presents preliminary results that help narrow these gaps. In conjunction with leaf area index (LAI) field campaigns we undertook measurements with an array of 7 broad-band (ca 40 nm) sensors covering the range 0.40–0.94 μm, plus 1 sensor for UVB (0.297 μm peak) and 1 for photosynthetically active radiation (PAR). Measurements focused on inside-forest shade conditions at sites 0 to ca 15 km from the Black Sea and at altitudes up to ca 120 m above sea level. Some of the sites were also studied using a high-resolution spectroradiometer. A sequential measuring strategy was necessary. This involves potentially large uncertainties, here addressed through estimations of the variability around the sinusoidal course of daylight. Light-quality regimes were found to be in general support of earlier studies of deciduous forests. Our data from the broad-band sensors and from the spectroradiometer are mutually supportive. They indicate a stronger red-shift below Q.f. canopies than below canopies in enclaves dominated by Fagus orientalis and Pinus sylvestris. Transmission in the range 0.50–0.55 μm increases beneath the three types of canopies, most pronounced in the Q.f. case. Analysis of relationships between the inside-forest to open-field irradiance ratio and LAI supports the use of Beer’s Law. We found a fairly strong relationship between the red (0.66 μm) to far-red (0.73 μm) irradiance ratios (R/FR) and LAI for the Q.f. forest. In quantitative terms, the result is new for this Q.f. region, and suggests further research to explore whether a two-sensor approach (0.66 and 0.73 μm) might offer possibilities for further low-cost mapping of the spatio-temporal patterns of R/FR and LAI in Strandzha. Such mapping would assist in further studies of the region’s forest biogeochemistry and vitality.  相似文献   
8.
Native and high pressure-treated (water suspensions, 650 MPa) waxy maize starch, containing mainly amylopectin, and Hylon VII, rich in amylose, were studied for their ability to generate free radicals upon thermal treatment at 180–230 °C. The electron paramagnetic resonance (EPR) spectroscopy was used to characterize the nature, number and stability of radicals. Various stable and short living (stabilized by N-tert-butyl-α-phenylnitrone (PBN) spin trap) radical species were formed. It was found, that at given conditions the waxy maize starch reveals higher ability to generate radicals, than Hylon VII. The presence of water and high pressure pretreatment of starches, both resulted in the reduction of the amount of thermally generated radicals. The decrease in crystallinity of waxy maize starch and of Hylon VII, occurring upon high pressure treatment, leads to the increase of the relative amount of fast rotating component in the EPR spectrum of both types of starches.  相似文献   
9.
Alterations in the hydrologic regime downstream from hydroelectric dams create a high invasibility to non-native species. This study aims to analyze the establishment of non-native Metynnis lippincottianus downstream of the Xingó Dam, lower São Francisco River, Brazil. Adults in reproduction were found throughout the study. Gonadosomatic index was higher in the reproductive phases and the species produces a large number of small oocytes. Hydrometric level and water flow data after the construction of Xingó Dam showed decrease in both parameters, facilitating the establishment of M. lippincottianus. Management actions are suggested to reduce the threat on the native biota.  相似文献   
10.
Summary Exclusive selection for yield raises, the harvest index of self-pollinated crops with little or no gain in total bipmass. In addition to selection for yield, it is suggested that efficient breeding for higher yield requires simultaneous selection for yield's three major, genetically controlled physiological components. The following are needed: (1) a superior rate of biomass accumulation. (2) a superior rate of actual yield accumulation in order to acquire a high harvest index, and (3) a time to harvest maturity that is neither shorter nor longer than the duration of the growing season. That duration is provided by the environment, which is the fourth major determinant of yield. Simultaneous selection is required because genetically established interconnections among the three major physiological components cause: (a) a correlation between the harvest index and days to maturity that is usually negative; (b) a correlation between the harvest index and total biomass that is often negative, and (c) a correlation between biomass and days to maturity that is usually positive. All three physiological components and the correlations among them can be quantified by yield system analysis (YSA) of yield trials. An additive main effects and multiplicative interaction (AMMI) statistical analysis can separate and quantify the genotype × environment interaction (G × E) effect on yield and on each physiological component that is caused by each genotype and by the different environment of each yield trial. The use of yield trials to select parents which have the highest rates of accumulation of both biomass and yield, in addition to selecting for the G × E that is specifically adapted to the site can accelerate advance toward the highest potential yield at each geographical site. Higher yield for many sites will raise average regional yield. Higher yield for multiple regions and continents will raise average yield on a world-wide basis. Genetic and physiological bases for lack of indirect selection for biomass from exclusive selection for yield are explained.  相似文献   
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