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101.
SMG-9 is a component of the NMD complex, a heterotetramer that also includes SMG-1 and SMG-8 in the complex. SMG-9 was also originally identified as a tyrosine-phosphorylated protein but the role of the phosphorylation is not yet known. In this study, we determined that IQGAP protein, an actin cytoskeleton modifier acts as a binding partner with SMG-9 and this binding is regulated by phosphorylation of SMG-9 at Tyr-41. SMG-9 is co-localized with IQGAP1 as a part of the process of actin enrichment in non-stimulated cells, but not in the EGF-stimulated cells. Furthermore, an increase in the ability of SMG-9 to bind to SMG-8 occurs in response to EGF stimulation. These results suggest that tyrosine phosphorylation of SMG-9 may play a role in the formation of the NMD complex in the cells stimulated by the growth factor.  相似文献   
102.
A real-time surveillance method is developed with emphasis on rapid and accurate detection of emerging outbreaks. We develop a model with relatively weak assumptions regarding the latent processes generating the observed data, ensuring a robust prediction of the spatiotemporal incidence surface. Estimation occurs via a local linear fitting combined with day-of-week effects, where spatial smoothing is handled by a novel distance metric that adjusts for population density. Detection of emerging outbreaks is carried out via residual analysis. Both daily residuals and AR model-based detrended residuals are used for detecting abnormalities in the data given that either a large daily residual or an increasing temporal trend in the residuals signals a potential outbreak, with the threshold for statistical significance determined using a resampling approach.  相似文献   
103.
Capture–recapture techniques have been used for considerable time to predict population size. Estimators usually rely on frequency counts for numbers of trappings; however, it may be the case that these are not available for a particular problem, for example if the original data set has been lost and only a summary table is available. Here, we investigate techniques for specific examples; the motivating example is an epidemiology study by Mosley et al., which focussed on a cholera outbreak in East Pakistan. To demonstrate the wider range of the technique, we also look at a study for predicting the long-term outlook of the AIDS epidemic using information on number of sexual partners. A new estimator is developed here which uses the EM algorithm to impute unobserved values and then uses these values in a similar way to the existing estimators. The results show that a truncated approach – mimicking the Chao lower bound approach – gives an improved estimate when population homogeneity is violated.  相似文献   
104.
Data from wildlife disease surveillance programs are used to inform implementation of disease control (e.g., vaccination, population reduction) in space and time. We developed an approach to increase detection of raccoon rabies in raccoons (Procyon lotor) and skunks (Mephitis mephitis) of Québec, Canada, and we examined the implications of using this approach for targeted surveillance. First we modeled the probability of a rabid animal relative to environmental characteristics of sampling locations. Rabid animals were more likely to be found in low-lying flat landscapes that had higher proportions of corn-forest edge habitat and hay agriculture, and that were within 20 km of one or more known rabies cases. From the model, we created 2 complementary risk maps to identify areas where rabid animals were most likely to be sampled. One map accounted for habitat and known rabies case locations, and can be used to define an infection zone from which surveillance can be targeted along the periphery to determine if disease is continuing to spread. The other map only accounted for habitat and can be used to locate areas most likely to contain rabid animals when the disease is present. In a further analysis we compared the 2 most successful methods for detecting raccoon rabies in Québec, given the disease was present. Government trapping operations (active surveillance) detected more cases in the short-term, but citizen notification (passive and enhanced) was more effective after 12 trapping days from which the initial rabies case was found. Our approach can benefit wildlife and public health agencies wanting to assess the disease status of regions by targeting surveillance to habitats most likely to contain infected animals and by defining the duration over which sampling methods are effective. © 2011 The Wildlife Society.  相似文献   
105.
Microsporidia are believed to play little or no role in outbreaks of the jack pine budworm, Choristoneura pinuspinus Freeman (Lepidoptrera: Tortricidae), because the short duration (2–4 years) of those outbreaks may not permit significant build-up of the pathogen. We conducted the first survey of Nosema sp. (Microsporidia: Nosematidae) over the course of a recent jack pine budworm outbreak in Ontario. Between 2004 and 2010 the outbreak defoliated a cumulative total of 1.78 million ha. Microscopic examination of ∼15,000 overwintering larvae collected over 6 years in sites with densities of 3 larvae per branch or more revealed widespread occurrence of Nosema at generally high infection intensities. The pathogen was present in 69.5% of the 518 plots that were monitored. Prevalence of infection was generally low (below 40% in 84% of plots with infected larvae) but reached high levels (80–95%) locally and increased rapidly in most infestations within 1–2 years of onset. We hypothesize that the habit of early-instar larvae to feed on developing male flowers (pollen cones) after spring emergence is critical in allowing rapid build-up of Nosema by increasing efficiency of horizontal transmission (higher density of both infected larvae and egested spores). Nosema infection may contribute to the complexity of jack pine budworm outbreak patterns by affecting egg recruitment and early-instar survival at the stand level in concert with known effects of budworm-induced reductions in pollen cone production on those processes.  相似文献   
106.
DICE     
The conventional view of CD95 (Fas/APO-1) is that it is a dedicated apoptosis-inducing receptor with important functions in immune cell homeostasis and in viral and tumor defense. There is an emerging recognition, however, that CD95 also has multiple non-apoptotic activities. In the context of cancer, CD95 was shown to have tumor-promoting activities, and the concept of this new function of CD95 in cancer is gaining traction. Recently, we showed that not only is CD95 a growth promoter for cancer cells, but, paradoxically, when either CD95 or CD95 ligand (CD95L) is removed, that virtually all cancer cells die through a process we have named DICE (death induced by CD95R/L elimination). In this perspective, I outline a hypothesis regarding the physiological function of DICE, and why it may be possible to use induction of DICE to treat many, if not most, cancers.  相似文献   
107.
正Dear Editor,With the intense crowding in mass gatherings such as Hajj,there is a high risk of acquisition of airborne in-fections with the potential for its transmission in the pilgrims’country of origin(Memish Z A,et al.,2014).The risk of importing serious infections from Hajj has escalated since the emergence of the Middle East respiratory syndrome coronavirus(MERS-CoV)in Saudi Arabia and other neighbouring countries from September2012.Active surveillance of Hajj pilgrims in 2012 and 2013  相似文献   
108.
We investigated spatial autocorrelation of female Aedes aegypti L. mosquito abundance from BG‐Sentinel trap and sticky ovitrap collections in Cairns, north Queensland, Australia. BG‐Sentinel trap collections in 2010 show a significant spatial autocorrelation across the study site and over a smaller spatial extent, while sticky ovitrap collections only indicate a non‐significant, weak spatial autocorrelation. The BG‐Sentinel trap collections were suitable for spatial interpolation using ordinary kriging and cokriging techniques. The uses of Premise Condition Index and potential breeding container data have helped improve our prediction of vector abundance. Semiovariograms and prediction maps indicate that the spatial autocorrelation of mosquito abundance determined by BG‐Sentinel traps extends farther compared to sticky ovitrap collections. Based on our data, fewer BG‐Sentinel traps are required to represent vector abundance at a series of houses compared to sticky ovitraps. A lack of spatial structure was observed following vector control treatment in the area. This finding has implications for the design and costs of dengue vector surveillance programs.  相似文献   
109.
Malaria, a globally significant mosquito-borne infectious disease, re-emerged in the Republic of Korea, and manifested annually in regions close to the demilitarized zone. Notably, Incheon Metropolitan City has witnessed an alarming upswing in malaria infections in recent years, drawing attention to this public health issue. This research was conducted to catch spatio-temporal and ecological landscape encompassing malaria patients and mosquito vectors in Incheon over the past decade. The top two incidences of malaria cases were found in Ganghwa-gun and Seo-gu, an occurrence potentially attributed to their geographic proximity to North Korea. Furthermore, the incidence of malaria infections displayed a seasonal pattern commencing in March, reaching its peak between June and August, and decreasing to a minimum in November. A correlation was noted between prevalence of malaria cases and number of mosquito breeding sites, such as ponds and rice fields within the region. Collectively, these research outcomes underlined the importance of systematically and holistically advocating mosquito elimination measures to enhance the efficacy of malaria eradication policies. These measures encompass the establishment of a robust mosquito outbreak surveillance system, targeted control of vector mosquitoes, residual pesticide spray, management of mosquito breeding sites, and adoption of repellents during outdoor activities.  相似文献   
110.
文礼章  张友军  朱亮  王少丽  肖强  杨中侠 《生态学报》2011,31(11):2978-2989
[摘要] 为进一步了解我国甜菜夜蛾Spodoptera exigua ( Hbner)间歇性暴发成灾的规律,作者应用时间序列分析技术研究了我国甜菜夜蛾间歇性暴发的时间序列波动规律。结果表明,在1949—2008年的60a中,我国甜菜夜蛾大尺度暴发总年频次为120次,各年度暴发次数(年频次)存在着非均衡性循环波动特征,并且在其波动过程中呈明显的上升趋势。按“年频次”强度,可将我国1949—2008年60a中甜菜夜蛾发生过程,划分成两个明显不同的阶段。第一阶段(1949—1984年)为平稳低发阶段,36a总年频次量为4次,年平均仅0.11次;第二阶段(1985—2008年)则为波浪式上升性高发阶段,24a总年频次为116次,年平均4.83次(为第一阶段的43.91倍))。按第二阶段24a(1985—2008)数据进行自相关系数和频谱图分析,结果表明,我国甜菜夜蛾大尺度暴发存在2.8a和11.2a2种不同长度的循环周期,其暴发趋势指数对滞后1a和滞后4a的影响为正相关,而对滞后5a和滞后6a的影响则为负相关。本文根据甜菜夜蛾暴发指数的非均衡周期性特征,建立了以时间序列为自变量的甜菜夜蛾暴发指数非均衡周期性预测模型,经回代结果检验,理论值与实测值之间无显著差异。  相似文献   
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