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DNA replication is a fundamental process of the cell that ensures accurate duplication of the genetic information and subsequent transfer to daughter cells. Various pertubations, originating from endogenous or exogenous sources, can interfere with proper progression and completion of the replication process, thus threatening genome integrity. Coordinated regulation of replication and the DNA damage response is therefore fundamental to counteract these challenges and ensure accurate synthesis of the genetic material under conditions of replication stress. In this review, we summarize the main sources of replication stress and the DNA damage signaling pathways that are activated in order to preserve genome integrity during DNA replication. We also discuss the association of replication stress and DNA damage in human disease and future perspectives in the field.  相似文献   
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Efforts to develop molecular tools for genetic analysis and breeding of common bean in the tropics are still limited. The number of microsatellite markers available for the crop is small compared to other crops of similar social and economic importance. As part of a project to broaden the use of molecular tools in bean breeding, a genomic library enriched for AG/TC repeat sequences was constructed for Phaseolus vulgaris. Twenty microsatellite markers were initially developed and 10 were characterized using a panel of 85 representative accessions of the bean gene bank. The number of alleles per marker ranged from three to 10. The polymorphism information content (PIC) varied from 0.23 to 0.80. The results indicate that the new markers can be readily used in genetically analysis of common bean.  相似文献   
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Regime shifts of climatic and environmental conditions potentially affect the productivity of fishery resources, posing challenges in stock management. The stocks of the Japanese flying squid (Todarodes pacificus) are suspected to suffer from regime shifts, but detecting the occurrence of regime shifts in this species is generally difficult and unreliable because the short-lived nature of this species inherently confounds the effect of regime shifts with observation and process errors. Here we developed a new state-space assessment model to evaluate the influence of regime shifts on the spawner-recruit relationship of the Japanese flying squid. The model simultaneously estimates the population dynamics of multiple stocks that could share some life history parameters, thereby stabilizing parameter inference. We demonstrate that two regime shifts in productivity around 1991 and 2015 caused two- to threefold changes of maximum sustainable yields. The model with regime shifts clarifies the relationship between fishing pressure and spawner abundance that is difficult to detect in a model with no regime shift. The state-space approach is a promising tool for accurately assessing stock status by separating the recruitment process from observation errors and is expected to contribute to the effective management of marine biological resources sensitive to regime shifts.  相似文献   
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《Chronobiology international》2013,30(5-6):467-469
The aim of this study was to demonstrate that a possible recurrence may pertain to migraine attacks (MAs). The study was carried out by checking the personal diaries of 30 migraine sufferers (“migraineurs”) who carefully annotated the date of their MA over twelve consecutive months. The group was composed of 15 males and 15 females, ranging in age from 17 to 37 years. The individual MAs were summarized in order to obtain the time-qualified frequency per each time period of recurrence. The periodicity in time data series was analysed by means of the Single Cosinor method. The rhythmometric analysis was found to be highly statistically significant; the circaseptan (P = 0.007) and circadian (P =0.004) recurrence of MA showing critical incidence on Sunday and in January, respectively. No circatrigintan periodicity was validated in relation to the solar and lunar months or menstrual cycle. These findings suggest to us a possible linkage of MA to environmental factors which entrain the routine of our lives. Because of the circaseptan and circannual repetitivities, common migraine syndrome was defined as a “weekly and seasonal headache”.  相似文献   
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Attention is increasingly being given to genetic resources in the deep seabed beyond the limits of national jurisdiction owing to their considerable potential scientific and economic value. At the same time, there are concerns that the increased demand for these genetic resources may result in their unsustainable collection or even in the extinction of species in the deep seabed. At present there is no specific legal framework governing these resources in international law. Thus, this article explores the relevant rules of international law applicable to the conservation and sustainable use of genetic resources in the deep seabed.  相似文献   
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Aim Species capable of vigorous growth under a wide range of environmental conditions should have a higher chance of becoming invasive after introduction into new regions. High performance across environments can be achieved either by constitutively expressed traits that allow for high resource uptake under different environmental conditions or by adaptive plasticity of traits. Here we test whether invasive and non‐invasive species differ in presumably adaptive plasticity. Location Europe (for native species); the rest of the world and North America in particular (for alien species). Methods We selected 14 congeneric pairs of European herbaceous species that have all been introduced elsewhere. One species of each pair is highly invasive elsewhere in the world, particularly so in North America, whereas the other species has not become invasive or has spread only to a limited degree. We grew native plant material of the 28 species under shaded and non‐shaded conditions in a common garden experiment, and measured biomass production and morphological traits that are frequently related to shade tolerance and avoidance. Results Invasive species had higher shoot–root ratios, tended to have longer leaf‐blades, and produced more biomass than congeneric non‐invasive species both under shaded and non‐shaded conditions. Plants responded to shading by increasing shoot–root ratios and specific leaf area. Surprisingly, these shade‐induced responses, which are widely considered to be adaptive, did not differ between invasive and non‐invasive species. Main conclusions We conclude that high biomass production across different light environments pre‐adapts species to become invasive, and that this is not mediated by plasticities of the morphological traits that we measured.  相似文献   
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