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341.
Summary The uptake of labelled and unlabelled N by wheat was measured in a field experiment using 15N-labelled ammonium nitrate fertilizer. The dry matter yield and N yields were significantly increased with fertilizer N application compared to those from unfertilized soil. The uptake of applied N by wheat ranged between 25 and 34%. Fertilizer N application increased the uptake of unlabelled soil N which was attributed to a positive priming effect or added N interaction. The added N interaction observed by applying 20, 60, and 120 kg fertilizer N was 11.4, 19.1, and 27.9 kg, corresponding to 26, 44 and 64%, respectively of the N taken up from unfertilized soil. The A values did not alter with the increase in fertilizer N application. The observed added N interaction may have been the result of pool substitution whereby added labelled fertilizer N stood proxy for unlabelled soil N. A significant correlation coefficient (r=0.996**) between the uptake of soil N and the dry matter yield showed that soil N was more important than fertilizer N in wheat production.  相似文献   
342.
The effect of different types of processing such as boiling, pressure cooking, puffing, frying, germination, and germination followed by cooking on the protein and carbohydrate digestibility of chickpea, horsegram and cowpea were studied in in vitro systems. In the case of chickpea, the protein digestibility was not significantly improved by any of the treatments. However, for horsegram and cowpea, improvement in protein digestibility was observed after some of the different processing treatments. Frying decreased the protein digestibility in all of the pulses. All of the treatments, except germination, caused a marked increase in in vitro carbohydrate digestibility.  相似文献   
343.
Background: Various frequencies of sperm aneuploidy are reported in sperms of subfertile patients compared to normal individuals. Moreover, sperm DNA damage is shown to be associated with male infertility. In this study, the rate of DNA damage and frequencies of aneuploidy in sperms of subfertile patients was investigated. Methods: Semen samples were obtained from healthy normal and subfertile (oligozoospermia, asthenozoospermia, and oligoasthenozoospermia) men. The frequency of aneuploidy was assessed using primed in situ labeling (PRINS) analysis with specific primers for chromosomes 18, 21, X, and Y. Sperm DNA damage was assessed using alkaline comet assay. Results: The mean frequencies of disomy for the patients were significantly higher than normal for all chromosomes (P<0.01). The extent of DNA damage in sperms of subfertiles was significantly higher than in normal individuals (P<0.001). The obtained results indicated that higher rate of DNA damages led to higher frequency of chromosomal disomy except for asthenozoospermia samples which exhibited higher rate of DNA damage and lower frequency of chromosomal disomy. Conclusions: These results demonstrate that men with oligozoospermia and oligoasthenozoospermia have an elevated risk for chromosome abnormalities in their sperm, particularly sex chromosomes. DNA damage might be involved in the process of malsegregation of chromosomes.Asthenozoospermia, DNA damage, Primed in situ labeling (PRINS), Comet assay  相似文献   
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346.
Journal of Crop Science and Biotechnology - Salinity stress is one of the most important abiotic stresses which reduce crop production worldwide. In this study, 17 morphological and agronomic...  相似文献   
347.
This study was carried out in 2014 at Isfahan University of Technology, Iran, to evaluate the responses of four rice varieties(Neda, Deylamani, Shiroudi and Domsorkh) to ambient(360 ± 50 μmol/mol) and elevated(700 ± 50 μmol/mol) air carbon dioxide(CO_2) concentrations under four salinity levels(0, 30, 60 and 90 mmol/L Na Cl). There was significant variation among rice varieties in response to elevated CO_2 concentration under the four salinity levels. Under non-saline condition, elevated CO_2 increased the dry weight of Neda, Deylamani and Domsorkh by 8%, 50% and 8%, respectively, but reversely decreased that of Shiroudi by 34%. Increasing CO_2 concentration significantly reduced the negative effects of salinity on Shiroudi, but these effects were even increased in Deylamani and Domsorkh under all the salinity levels and in Neda only under 30 and 60 mmol/L Na Cl. Significant correlations were established between plant dry weight, SPAD value and leaf area under both CO_2 levels. However, this trend was observed only at ambient CO_2 concentration in the presence of soluble carbohydrates. The results revealed the genotype and salinity dependence of the effects of CO_2 concentrations on the rice traits investigated.  相似文献   
348.
Two Fusarium strains, isolated from Asparagus in Italy and Musa in Vietnam respectively, proved to be members of an undescribed clade within the Fusarium solani species complex based on phylogenetic species recognition on ITS, partial RPB2 and EF-1α gene fragments. Macro- and micro-morphological investigations followed with physiological studies done on this new species: Fusarium ershadii sp. nov can be distinguished by its conidial morphology. Both isolates of Fusarium ershadii were shown to be pathogenic to the monocot Asparagus officinalis when inoculated on roots and induced hollow root symptoms within two weeks in Asparagus officinalis seedlings. In comparison mild disease symptoms were observed by the same strains on Musa acuminata seedlings.  相似文献   
349.
The status of woody plants in dry-land systems is a fundamental determinant of key ecosystem processes. Monitoring of this status plays an important role in understanding the dynamics of woody plants in arid and semi-arid ecosystems. The present study determined the dynamism of the Zagros forests in Iran using Remote Sensing and Geographic Information System techniques and statistical science. The results show that the density of trees varied from 10 to 53 % according to the physiographic and climatic conditions of semi-arid regions. The best and lowest correlation between vegetation indices and forest density were obtained for the global environmental monitoring index (GEMI; R 2 = 0.94) and soil adjust vegetation index (R 2 = 0.81), respectively. GEMI is used to monitor land use changes over a 10-year period. Results show that 2720 ha2 of forest have been destroyed by human interference and tillage on steep slopes during this period which also resulted in the loss of the fertile soil layer. GEMI determined the areas with a biomass of trees and could normally separate border regions with low biomass density of trees from regions without canopy cover. The results revealed that assessment of forest and vegetation cover in arid and semi-arid arduous forest regions using satellite digital numbers and ordinary sampling is subject to uncertainty. A stratified grouping procedure should be established to increase the accuracy of assessment.  相似文献   
350.
Phosphorus (P) sufficiency during seed formation and development can affect the quality of seeds production. For increasing P content of black seed (Nigella sativa) in a calcareous soil, series of experiments were conducted in completely randomized factorial design with 4 replications at the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2012 and 2013. The combinations of vermicompost (V), sulfur (S), and Thiobacillus bacteria (T) were mixed with a calcareous soil fertilized with 0, 30 and 60 kg P ha?1 in pots and incubated for 63 days. At the end of incubation period, black seeds were sown in the pots and plants were grown to maturity. Results showed that S+T and V treatments were significantly increased soil available P, emergence, plant P content, seed yield and vigor of the seeds production. There were positive relationship between soil and plant P concentration with the quality of seeds production.  相似文献   
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