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Aflatoxin (AF) contamination was determined in 40 chili samples, representing 3 varieties from Punjab, Pakistan, by HPLC with fluorescence detection. Total AF were determined in varieties Longi (n = 15), Wonder hot (n = 12), and Skyline 1 (n = 13), and the concentrations were high in some samples. AF were detected in 9 (60%), 8 (67%), and 7 (54%) of Longi, Wonder hot, and Skyline 1 samples, respectively; concentration ranged from 4.7 to 34.6, 1.0 to 14.3, and 7.8 to 15.6 μg/kg, respectively. The percentage of samples greater than the European Union statutory limit for AFB1 and total AF in spices were 53% and 53%, 53% and 8%, and 53% and 38% for Longi, Wonder hot, and Skyline 1, respectively. Significant differences at α < 0.05 between mean concentration of AF in Longi (15.9 ± 0.6 μg/kg) and Wonder hot (5.8 ± 0.3 μg/kg) were determined. In conclusion, choosing the variety demonstrating the lowest AF concentration from various chili samples will assist in improving product quality. This preferred variety is Wonder Hot as described herein.  相似文献   
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A significantly increased water regime can lead to inundation of rivers, creeks and surrounding floodplains- and thus impact on the temporal dynamics of both the extant vegetation and the dormant, but viable soil-seed bank of riparian corridors. The study documented changes in the soil seed-bank along riparian corridors before and after a major flood event in January 2011 in southeast Queensland, Australia. The study site was a major river (the Mooleyember creek) near Roma, Central Queensland impacted by the extreme flood event and where baseline ecological data on riparian seed-bank populations have previously been collected in 2007, 2008 and 2009. After the major flood event, we collected further soil samples from the same locations in spring/summer (November–December 2011) and in early autumn (March 2012). Thereafter, the soils were exposed to adequate warmth and moisture under glasshouse conditions, and emerged seedlings identified taxonomically. Flooding increased seed-bank abundance but decreased its species richness and diversity. However, flood impact was less than that of yearly effect but greater than that of seasonal variation. Seeds of trees and shrubs were few in the soil, and were negatively affected by the flood; those of herbaceous and graminoids were numerous and proliferate after the flood. Seed-banks of weedy and/or exotic species were no more affected by the flood than those of native and/or non-invasive species. Overall, the studied riparian zone showed evidence of a quick recovery of its seed-bank over time, and can be considered to be resilient to an extreme flood event.  相似文献   
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ABSTRACT

Experiments were carried out with various salts and their combinations to ascertain the impact of these salts on seedling traits of fodder species and to identify tolerant species. Length-based traits showed a repressed effect, whereas weight-based traits were increased under salt stress. Furthermore, accumulation of Na+, Ca2+, and Cl? ions and metals (Cu2+, Fe2+, and Al3+) increased in various organs of seedlings due to various salt treatments. Contrastingly, K+, K+/Na+, and Ca2+/Cl? decreased, showing priority for specific salts. Seedling traits, such as shoot length sensitivity and shoot biomass, provide an effective mean of selection for tolerant or susceptible genotypes. Diverse types of tolerance mechanisms were present in cultivars to detoxify the effect of ions and metals. Cultivars that showed low susceptibility index, high shoot biomass, and high metal concentration were salt includers and could be utilized for bioremediation of the affected areas, whereas tolerant cultivars that showed low susceptibility index, metals concentration, and comparable shoot biomass to that of the control were salt excluders and could be utilized for fodder purposes.  相似文献   
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Though recovery of consciousness after drug overdose may occur within a day or two, the drug itself may not finally leave the brain for another one to three weeks, and at this late time a withdrawal syndrome can occur, with insomnia, restlessness, raised paradoxical (R.E.M.) sleep, epileptic phenomena, and even delirium. It is proposed that a high degree of drug-tolerance and dependence can be rapidly acquired after overdose.Abnormal sleep features of 10 patients resolved only slowly over a period of up to two months after overdose. The data support the view that R.E.M. sleep is concerned with processes of brain repair.  相似文献   
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It has been known for more than a century that rhizobia can promote the growth of legumes through the formation of nitrogen-fixing nodules, but the interaction of rhizobia with non-legumes has been neglected as an experimental system. During the last couple of decades, work on rhizobial interaction with non-legumes has been done progressively and it has been demonstrated that rhizobia can associate with roots of non-legumes also, without forming true nodules, and can promote their growth by using one or more of the direct or indirect mechanisms of actions. Phytohormone production, secretion of other chemicals like lipo-chito-oligosaccharides (LCOs) and lumichrome, solubilization of precipitated phosphorus and mineralization of organic P, improvement in uptake of plant nutrients by altering root morphology, production of siderophores to meet the iron requirements of the plant under iron-stressed conditions and lowering of ethylene level through ACC deaminase enzyme, are some examples of the rhizobial mechanisms with direct positive effects on non-leguminous plant growth. Indirectly, rhizobia improve the growth of non-legumes through biocontrol of pathogens via antibiosis, parasitism or competition with pathogens for nutrients and space, by inducing systemic resistance in the host plant and through increasing root adhering soil by releasing exopolysaccarides which regulate the water movement and facilitate the root growth. However, no influence or even inhibitory effects of rhizobial inoculation on non-legumes has also been demonstrated in some cases. Plant growth promoting mechanisms of rhizobia and its practical application in non-legumes are the major focus of this review.  相似文献   
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BackgroundUnderstanding how knowledge, attitudes and practices regarding leprosy differ in endemic countries can help us develop targeted educational and behavioural change interventions. This study aimed to examine the differences and commonalities in and determinants of knowledge, attitudes, practices and fears regarding leprosy in endemic districts in India and Indonesia.Principle findingsA cross-sectional mixed-methods design was used. Persons affected by leprosy, their close contacts, community members and health workers were included. Through interview-administered questionnaires we assessed knowledge, attitudes, practices and fears with the KAP measure, EMIC-CSS and SDS. In addition, semi-structured interviews and focus group discussions were conducted. The quantitative data were analysed using stepwise multivariate regression. Determinants of knowledge and stigma that were examined included age, gender, participant type, education, occupation, knowing someone affected by leprosy and district. The qualitative data were analysed using open, inductive coding and content analysis.We administered questionnaires to 2344 participants (46% from India, 54% from Indonesia) as an interview. In addition, 110 participants were interviewed in-depth and 60 participants were included in focus group discussions. Knowledge levels were low in both countries: 88% of the participants in India and 90% of the participants in Indonesia had inadequate knowledge of leprosy. In both countries, cause, mode of transmission, early symptoms and contagiousness of leprosy was least known, and treatment and treatability of leprosy was best known. In both countries, health workers had the highest leprosy knowledge levels and community members the highest stigma levels (a mean score of up to 17.4 on the EMIC-CSS and 9.1 on the SDS). Data from the interviews indicated that people were afraid of being infected by leprosy. Local beliefs and misconceptions differed, for instance that leprosy is in the family for seven generations (Indonesia) or that leprosy is a result of karma (India). The determinants of leprosy knowledge and stigma explained 10–29% of the variability in level of knowledge and 3–10% of the variability in level of stigma.ConclusionOur findings show the importance of investigating the perceptions regarding leprosy prior to educational interventions in communities: even though knowledge levels were similar, local beliefs and misconceptions differed per setting. The potential determinants we included in our study explained very little of the variability in level of knowledge and stigma and should be explored further. Detailed knowledge of local knowledge gaps, beliefs and fears can help tailor health education to local circumstances.  相似文献   
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