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11.
Little detailed evidence has previously been available regarding the uptake rate or prevalence of energy efficiency interventions among specific household groups. This study uses the Home Energy Efficiency Database (HEED) to investigate both the combination of measures that have been installed, and in which dwellings, according to key neighbourhood socio-demographic variables, including income and tenure. Analysis of 2000–07 data indicates that approximately 40% (9.3 million) dwellings in England had approximately 23.7 million efficiency measures installed, with an average of 2.5 measures per dwelling. Building fabric-related measures were the most frequent (e.g. cavity wall insulation, loft insulation and glazing) with an average of 2.1 million installed each year. Dwellings with the highest number of fabric interventions (the top 20%) were more likely to be found in areas with low income, with more owner-occupied dwellings, experiencing lower winter temperatures, having a lower proportion of flats, and having a slightly higher proportion of older adults and children. Energy efficiency installations have tended to occur among specific types of households or parts of the building stock. These findings have implications for the design of future government programmes for targeting energy efficiency measures to specific household groups or dwelling types.  相似文献   
12.
Stroke remains the fifth leading cause of mortality in the United States with an annual rate of over 128,000 deaths per year. Differences in incidence, pathogenesis, and clinical outcome have long been noted when comparing ischemic stroke among different ethnicities. The observation that racial disparities exist in clinical outcomes after stroke has resulted in genetic studies focusing on specific polymorphisms. Some studies have focused on matrix metalloproteinases (MMPs). MMPs are a ubiquitous group of proteins with extensive roles that include extracellular matrix remodeling and blood-brain barrier disruption. MMPs play an important role in ischemic stroke pathophysiology and clinical outcome. This review will evaluate the evidence for associations between polymorphisms in MMP-1, 2, 3, 9, and 12 with ischemic stroke incidence, pathophysiology, and clinical outcome. The role of polymorphisms in MMP genes may influence the presentation of ischemic stroke and be influenced by racial and ethnic background. However, contradictory evidence for the role of MMP polymorphisms does exist in the literature, and further studies will be necessary to consolidate our understanding of these multi-faceted proteins.  相似文献   
13.
The consumption of illicit drugs causes indisputable societal and economic damage. Therefore it is necessary to know their usage levels and trends for undertaking targeted actions to reduce their use. Recently, a new approach (namely sewage epidemiology) was developed for the estimation of illicit drug use based on measurements of urinary excreted illicit drugs and their metabolites in untreated wastewater. This review aims at critically evaluating the published literature and identifying research gaps of sewage epidemiology. Firstly, the existing analytical procedures for the determination of the four most used classes of illicit drugs worldwide (cannabis, cocaine, opiates and amphetamine-like stimulants) and their metabolites in wastewater are summarized and discussed. The focus lies on the sample preparation and on the analysis with chromatographic techniques coupled to mass spectrometry. Secondly, back-calculations used to transform measured concentrations in wastewater (in ng/L) into an amount of used illicit drug (in g/day per 1000 inhabitants or doses/day per 1000 inhabitants) are discussed in detail for the four groups of illicit drugs. Sewage epidemiology data from Spain, Belgium, UK, Italy, Switzerland and USA are summarized and compared with data from international organisations, such as the European Monitoring Centre for Drug and Drug Addiction (EMCDDA) and the United Nations Office on Drugs and Crime (UNODC). The results derived from wastewater analysis show in general good agreement with existing prevalence data (percentage of a population that uses illicit drugs at a given time) and demonstrate the potential of sewage epidemiology. However, this review confirms that future work should focus on further optimisation and standardisation of various important parameters (e.g. sample collection and back-calculations). In the future, sewage epidemiology could be used in routine drug monitoring campaigns as a valuable tool in addition to the classical socio-epidemiological studies for the determination of local, national and international illicit drug use.  相似文献   
14.
In a recent update of the Dutch contingency plan for controlling outbreaks of classical swine fever (CSF), emergency vaccination is preferred to large-scale pre-emptive culling. This policy change raised two questions: can emergency vaccination be as effective as pre-emptive culling, and what are the implications for showing freedom of infection? Here, we integrate quantitative information available on CSF virus transmission and vaccination effects into a stochastic mathematical model that describes the transmission dynamics at the level of animals, farms and livestock areas. This multilevel approach connects individual-level interventions to large-scale effects. Using this model, we compare the performance of five different control strategies applied to hypothetical CSF epidemics in The Netherlands and, for each of these strategies, we study the properties of three different screening scenarios to show freedom of infection. We find that vaccination in a ring of 2 km radius around a detected infection source is as effective as ring culling in a 1 km radius. Feasible screening scenarios, adapted to the use of emergency vaccination, can reduce the enhanced risks of (initially) undetected farm outbreaks by targeting vaccinated farms. Altogether, our results suggest that emergency vaccination against CSF can be equally effective and safe as pre-emptive culling.  相似文献   
15.
A prospective study was used to: (1) quantify potential risk factors for whiplash associated disorder following a rear-end motor vehicle collision; and (2) develop a simple clinical decision rule for the early identification of patients at risk for long-term whiplash associated disorder. Between 1 October 1995 and 31 March 1998, 446 adults involved in rear-end collisions presented to the only two emergency departments serving Kingston, Ontario. Eligible and consenting subjects (n = 353) were contacted by telephone soon after the collisions then at multiple occasions up to 2 years post-collision. Bivariate and multiple logistic regression analyses were used to identify potential risk factors for persistent symptoms. A software package that uses Chi-squared automatic interaction detection and classification and regression trees was used to develop a simple clinical decision rule for the identification of patients at high and low risk for persistent whiplash associated disorder. Risk factors identified by regression analyses included: increased age, number of initial physical symptoms, and early development of the following symptoms: upper back pain, upper extremity numbness or weakness, or disturbances in vision. A simple clinical decision rule that requires asking up to three basic questions of each patient was derived and would have identified the 118 cases of persistent whiplash associated disorder with a sensitivity of 91.5% (95% confidence interval: 86.5, 96.6) and a specificity of 51.4% (44.7, 58.1). This study confirmed the importance of several risk factors for whiplash associated disorder following rear-end motor vehicle collisions.  相似文献   
16.
The discovery of three individuals suspected to have contracted variant Creutzfeldt-Jakob disease (vCJD) through blood transfusions has heightened concerns that a secondary epidemic via human-to-human transmission could occur in the UK. The Department of Health responded immediately to this threat by banning those who had received blood transfusions since 1980 from donating blood. In this paper, we conduct a sensitivity analysis to explore the potential size of a blood-borne vCJD epidemic and investigate the effectiveness of public health interventions. A mathematical model was developed together with an expression for the basic reproduction number (R0). The sensitivity of model predictions to unknown parameters determining the transmission of vCJD via infected blood was assessed under pessimistic modelling assumptions. We found that the size of the epidemic (up until 2080) was bounded above by 900 cases, with self-sustaining epidemics (R0>1) also possible; but the scenarios under which such epidemics could arise were found to be biologically implausible. Under optimistic assumptions, public health interventions reduced the upper bound to 250 and further still when only biologically plausible scenarios were considered. Our results support the belief that scenarios leading to large or self-sustaining epidemics are possible but unlikely, and that public health interventions were effective.  相似文献   
17.
Epidemiology studies of recreational waters have demonstrated that swimmers exposed to faecally-contaminated recreational waters are at risk of excess gastrointestinal illness. Epidemiology studies provide valuable information on the nature and extent of health effects, the magnitude of risks, and how these risks are modified or associated with levels of faecal contamination and other measures of pollution. However, such studies have not provided information about the specific microbial agents that are responsible for the observed illnesses in swimmers. The objective of this work was to understand more fully the reported epidemiologic results from studies conducted on the Great Lakes in the US during 2003 and 2004 by identifying pathogens that could have caused the observed illnesses in those studies. We used a Quantitative Microbial Risk Assessment (QMRA) approach to estimate the likelihood of pathogen-induced adverse health effects. The reference pathogens used for this analysis were Norovirus, rotavirus, adenovirus, Cryptosporidium spp., Giardia lamblia, Campylobacter jejuni, Salmonella enterica, and Escherichia coli O157:H7. Two QMRA-based approaches were used to estimate the pathogen combinations that would be consistent with observed illness rates: in the first, swimming-associated gastrointestinal (GI) illnesses were assumed to occur in the same proportion as known illnesses in the US due to all non-foodborne sources, and in the second, pathogens were assumed to occur in the recreational waters in the same proportion as they occur in disinfected secondary effluent. The results indicate that human enteric viruses and in particular, Norovirus could have caused the vast majority of the observed swimming-associated GI illnesses during the 2003/2004 water epidemiology studies. Evaluation of the time-to-onset of illness strongly supports the principal finding and sensitivity analyses support the overall trends of the analyses even given their substantial uncertainties.  相似文献   
18.
Memorializes B. H. Fox, a research scientist internationally known for his work on the epidemiology and etiology of cancer. Fox was instrumental in establishing a new field of research best described as biopsychosocial cancer epidemiology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
19.
Recent developments in molecular sub-typing of Listeria monocytogenes   总被引:1,自引:0,他引:1  
As a vast majority of the human listeriosis cases are caused by serotypes 1/2a, 1/2b and 4b strains, it is imperative that strains from clinical as well as from food and environment are further characterised so that accurate and timely epidemiological determination of sources of the contamination can be established to minimise the disease burden. Recent developments in the field of genomics provide a great opportunity to use these tools towards the development of molecular sub-typing techniques with a greater degree of discrimination spanning the entire length of the genome. This brief review summarises a few of these DNA-based techniques with an emphasis on DNA microarray and other whole genome sequencing-based approaches and their usefulness in Listeria monocytogenes sub-typing and outbreak investigations.  相似文献   
20.
Low and not high cholesterol seems to predict high mortality in hemodialysis (HD) patients. The confirmation of this reverse epidemiology as well as its possible interconnection with the increased inflammatory activity observed in this population is being explored in the present study. A group of 136 HD patients was prospectively studied for 2 years, and cardiovascular disease (CVD) as well as all-cause mortality and morbidity were recorded. Baseline lipid profile, inflammatory status, and patients' characteristics were studied as potential survival and hospitalization predictors. During the 24-month follow-up, 21 deaths (52.4% due to CVD) and 38 hospitalizations (55.3% due to CVD) were recorded. In multivariate Cox regression analysis, decreased interleukin-10 (IL-10) and decreased total serum cholesterol (TChol) were the only independent predictors of CVD mortality while C-reactive protein and decreased TChol predicted all-cause mortality. Interleukin-10 at baseline was 11.29 ± 21.49 vs. 5.51 ± 4.57 pg/mL (P<0.018) and TChol 167.37 ± 47.84 vs.122.04 ± 26.48 mg/dL (P<0.000) in survivors vs. nonsurvivors from CVD, while C-reactive protein at baseline was 9.37 ± 11.54 vs. 23.15 ± 18.76 mg/L (P<0.000) and TChol 169.26 ± 46.42 vs. 133.26 ± 46.33 mg/dL (P<0.003) in survivors vs. nonsurvivors from any cause of death. Using the same method of statistical analysis, IL-6 and decreased soluble gp130 (sgp130)—an antagonist of IL-6 action—were found to be the only independent prognostic factors for hospitalization due to CVD while decreased soluble gp130 remained the sole predictor of hospitalization due to any cause. In conclusion, reverse epidemiology regarding cholesterol is confirmed in the present study. Furthermore, inflammatory activity also predicts, independently of or in conjunction with low-cholesterol, CVD and all-cause morbidity and mortality in HD patients.  相似文献   
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