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51.
《Ergonomics》2012,55(6):649-657
The purpose of this study was to establish a basis for the use of a device for measuring vibrotactile perception thresholds for epidemiological purposes on a series of non-exposed populations. Vibrotactile perception thresholds (VPTs) were measured with a vibrometer in 218 men and 160 women belonging to two non-exposed male blue collar populations, one white-collar population and one age and gender stratified sample of the general population. VPTs were measured on the middle and the little finger of the dominant hand at 31.5 and 125 Hz. The VPTs were expressed in dB and the effect of a series of factors including the population, age, gender and digital temperature was assessed in a regression analysis weighted by the inverse variance of the measurements. Adjusted for age, no significant difference between the VPTs in the four male populations was observed. At frequency 125 Hz, the effect of age (0.3 dB per year) was more important than at frequency 31.5 Hz (0.2 dB per year). In the two female populations, the results were less stable than among males and the VPTs were higher than among males. However, the age-dependence was similar among males and females. The within-test variance is a valuable indicator of the quality of the VPT measurements. Weighting by its inverse improved the fit of the regression models. Normal values for VPTs in non-exposed populations were obtained, which were reproducible in four separate populations.  相似文献   
52.
Corpet DE 《Meat science》2011,89(3):310-316
The effect of meat consumption on cancer risk is a controversial issue. However, recent meta-analyses show that high consumers of cured meats and red meat are at increased risk of colorectal cancer. This increase is significant but modest (20-30%). Current WCRF-AICR recommendations are to eat no more than 500 g per week of red meat, and to avoid processed meat. Moreover, our studies show that beef meat and cured pork meat promote colon carcinogenesis in rats. The major promoter in meat is heme iron, via N-nitrosation or fat peroxidation. Dietary additives can suppress the toxic effects of heme iron. For instance, promotion of colon carcinogenesis in rats by cooked, nitrite-treated and oxidized high-heme cured meat was suppressed by dietary calcium and by α-tocopherol, and a study in volunteers supported these protective effects in humans. These additives, and others still under study, could provide an acceptable way to prevent colorectal cancer.  相似文献   
53.
Thoroughbred jumps racing jockeys have a fall rate greater than their flat racing counterparts. Previous studies have focused on factors that contribute to falls by horses but, to date, there has not been a study of risk factors for falls to jockeys in jumps races. Data on race-day falls were extracted from stipendiary stewards reports lodged with Principal Racing Authorities following each race meeting. Denominator data were provided by Racing Information Services Australia on races conducted from August 2002 until July 2009. Univariable and multivariable analyses, estimating incidence rate ratios, were conducted using Poisson regression. In multivariable analysis in hurdle racing, important predictors of falls were higher club level, larger field size, greater prize money, provisionally licenced jockeys and older jockeys. There were significant interactions between jockey licence and prize money; jockey age and previous rides this meeting; race grade and race distance; horse age and field size; and club level and field size. In steeplechase racing, important predictors were type of jump with lowest fall rates in races over Mark III jumps compared to standard fences, provisionally licenced jockeys, jockeys having had previous rides at a meeting, and larger field size. There were significant interactions between the number of previous starts by the horse and field size; race distance and prize money; and race distance and previous rides this meeting. This study has identified factors for falls in jumps racing that could form the basis for targeted strategies to improve occupational health and safety standards.  相似文献   
54.
2000年~2003年广西细菌性食物中毒流行病学分析   总被引:8,自引:1,他引:8       下载免费PDF全文
为掌握广西细菌性食物中毒流行病学特点及其流行原因,为采取针对性防治对策提供科学依据,对2000年~2003年广西各地食物中毒报表与专题调查报告进行统计分析。2000年~2003年发生细菌性食物中毒105起,进食17915人,中毒3557人,中毒发病率19.85%,死亡34人,分别占同期广西各类食物中毒起数的22.83%,中毒人数的38.29%和死亡人数的27.64%;4~10月份是中毒高发月份;66.71%的中毒和100.00%的死亡人数集中在西北部的河池、百色以及中心城市南宁、柳州、桂林市;中毒原因主要是农村家庭聚餐、饮食服务单位、集体食堂制作的食物因原料(重点为肉类、谷类及制品)污染或加工不当、生熟交叉污染等所致;病原体构成第一位是沙门菌,其它依次为蜡样芽胞杆菌、金黄色葡萄球菌、变形杆菌、副溶血弧菌、椰毒假单胞菌、致病性大肠杆菌等;而进食人数发病率最高的是椰毒假单胞菌(98.61%),其次是沙门菌(38.58%)、金黄色葡萄球菌肠毒素(34.48%),最低的是由蜡样芽胞杆菌引起的食物中毒为10.65%;死亡病例全部系椰毒假单胞菌所产生的毒素污染酵米面所致。细菌性食物中毒是广西食物中毒的重要组成部分;不同食源性致病菌(毒素)引起的进食人员中毒发病率差异有显著性(P<0.01);广西西北部农村、饮食业和学校集体食堂等是细菌性食物中毒防制  相似文献   
55.
A case of listeriosis was associated with the consumption of a soft cheese produced in England. Goats cheese and other products from the same food manufacturer were examined for the presence of Listeria over the following 11 months. Listeria monocytogenes was isolated from 16 of 25 cheese samples on retail sale, 12 of 24 cheese samples obtained directly from the factory, and from shelving within the plant. Phage-typing of 68 isolates of L. monocytogenes from cheese samples and the factory showed that 66 (97%) were indistinguishable from the strain isolated from the patient's cerebrospinal fluid and stool. L. monocytogenes was not isolated from seven goats milk or two yoghurt samples. Listeria innocua was isolated from 10 cheese samples, two of which contained no other species of Listeria. Levels of L. monocytogenes shortly after production were low (<10/g), but were higher (105–107 cfu/g) in six of the 16 cheese samples obtained from retail outlets. Multiplication of L. monocytogenes was demonstrated in cheeses contaminated at the factory and held at 4°C in the laboratory.  相似文献   
56.
This retrospective study explores the association between occupational noise exposure at the time of hearing tests, permanent noise-induced hearing loss and work-related accident risk. Log-binomial analysis was used to first ascertain the association between study variables according to activity sector (North American Industry Classification System, NAICS) and accident context while controlling for age. Second part of the paper estimates the overall number of accidents attributable to occupational noise or the associated hearing loss (excess fraction). Study was carried on a sample of 52,982 male workers exposed to a minimum of 80dBA on a daily basis and whose hearing was examined at least once between 1983 and 1996 by public health authorities of Quebec. These participants evidenced bilateral average hearing threshold levels at 3, 4 and 6kHz ranging from normal (/=90dBA) and noise-induced hearing loss.  相似文献   
57.
Fossil fuel energy use in heating and cooling buildings is considered to be a major contributor to observed climate change effects, so there is an environmental imperative to reduce energy use in buildings. We should also improve buildings’ energy efficiency on health grounds. Climate change is predicted to produce more frequent extreme weather events, while epidemiological evidence indicates relationships between ambient temperature and ill health. This points to the need for addressing both climate change itself and the way buildings mediate outdoor conditions, for the sake of vulnerable occupants. The UK government requires evidence in support of policy-making concerning energy use in buildings and consequences for health. This paper reviews epidemiological research to illustrate problems associated with measuring the direct health impact of indoor temperatures, for which evidence remains limited. Conventionally, temperature-related health effects are discussed in terms of seasonal excess deaths. The paper goes on to describe a population-based study in London that considers morbidity rather than mortality. A new methodology is developed that links the risk of cold homes with excess winter hospital episodes, demonstrating its potential for identifying small areas for priority action on improving domestic energy efficiency in terms of health as well as the environment.  相似文献   
58.
The amount of lead in the superficial enamel of deciduous teeth from 4- and 5-year-old children was determined by means of an enamel biopsy followed by lead analysis by graphite furnace atomic absorption spectrometry. Children examined in this study (n=329) attended public preschools in the city of Piracicaba, SP, Brazil. The selection of preschools was based on geographical location: some were located in an industrial area of the city, whereas others were located in an area devoid of industries. The objectives of this study were (1) to test whether enamel biopsies were an appropriate method for lead content population screening in young children; (2) to verify the lead content of superficial enamel of preschool children's deciduous teeth and to compare the results obtained from children exposed to different environments; (3) to analyze how biopsy depth correlated with lead content and affected comparisons between groups. An adhesive tape with a central hole (diameter=1.6 mm) was placed on one of the upper central incisors. Five microliters of 1.6 mol l−1 HCl in 70% glycerol (v/v) were applied to this area for 20 s, followed by a rinse with 5-μl ultrapurified water for 10 s. It was shown that the technique was feasible for population studies on young children. The lead concentration in enamel biopsies from the industrial area children (median: 169 ppm Pb) was significantly higher than that from the children living far from industries (118.1 ppm Pb) (P<0.0001). Analysis of the data showed that biopsies deeper than 3.9 μm gave more reliable results for comparisons between groups. To our knowledge, this study is the first to use an enamel microbiopsy to characterize a large sample of young children in vivo for lead monitoring in teeth.  相似文献   
59.
目的: 初步了解中国皖南地区恶性淋巴瘤的构成情况,探讨本地区恶性淋巴瘤的流行病学特点。方法: 收集皖南医学院附属弋矶山医院病理科2003.03-2012.03间诊断明确的淋巴瘤标本,全部病例经重新HE切片染色、免疫组化(Envision二步)法辅助检测,部分病例采用EBER原位杂交法(EBER-ISH)协助诊断,并参照2008版WHO关于淋巴造血组织肿瘤的分类进行组织学诊断和分型。结果: 728例中霍奇金淋巴瘤(HL)占 9.34%(68/728),非霍奇金淋巴瘤(NHL)占 90.66%(660/728),NHL中B细胞来源占 77.42%(511/660)。T/NK细胞来源占 22.58%(149/660),此外,在收集的淋巴瘤标本中,弥漫性大B细胞淋巴瘤(DLBCL)占 49.73%(362/728),其余较多见的六大类型依次为结外NK/T细胞淋巴瘤61例占 8.37%,黏膜相关淋巴组织结外边缘区淋巴瘤(MALT)56例占 7.69%,外周T细胞淋巴瘤50例占 6.87%,套细胞淋巴瘤36例占 4.95%,经典霍奇金淋巴瘤(结节硬化型)32例占 4.40%,经典霍奇金淋巴瘤(混合细胞型)31例占 4.26%。男性433例,女性295例,男女性别比为 1.47∶1,年龄最小5岁,最大90岁,中位年龄61岁;血管免疫母细胞性T细胞淋巴瘤男性发病率为 86.6%(13/15)。最好发的部位依次为淋巴结、胃、肠、鼻咽部、扁桃体、涎腺、甲状腺、眼眶、骨和脾等。结论: 中国皖南地区HL以结节硬化型和混合型居多,未见"双峰性",且以原发于左颈淋巴结多见。NHL中还是DLBCL为最多见,淋巴瘤血管免疫母细胞性T细胞淋巴瘤男性、67岁以上发病率较高,提示恶性淋巴瘤在亚类和分类上具有明显地域性的差异。  相似文献   
60.
Bicycles are a common mode of transportation and injured bicyclists cause a substantial burden on the medical sector. In Sweden, about half of fatally injured bicyclists are 65 years or older. This study analyzes the injury mechanisms, injuries, and consequences among bicyclists 65 years or older and compare with younger bicyclists (≤64) and older adults as passenger car drivers, to give a basis for an injury preventive discussion for this age group. Umeå University Hospital's primary catchments area had 142,000 inhabitants in 2006. Nearly all injured road users in the well-defined geographic area are treated at this hospital and a 10-year data set (N = 456) of injured bicyclists aged 65+ from the hospital's continuous injury registration (1997-2006) was analyzed. The results show that the annual injury incidence was 2.4 and 2.2 per 1000 men and women, respectively, aged 65 or older. For men the incidence rate was constant in the three age groups 65-74, 75-84 and 85+, while it decreased strongly for women. The incidence rate for old adults as passenger car drivers and younger bicyclists was 1.0 and 4.6, respectively. Most frequent injury mechanisms were falls when getting on or off a bicycle (20%) and by potholes or irregularities on the ground, edge of a sidewalk, or similar (13%). Only 6% were hit by cars, trucks, or buses. Half of the injured suffered fractures or dislocations, and 10% suffered concussion or more serious intracranial injuries. Getting on or off the bicycle caused most fractures (especially a high fraction of the hip and femur fractures) and resulted in 27% of all inpatient days in hospital. Three individuals died. One-third of the injured were treated as inpatients for a total of 1413 days (on average 9 days), with 69% of the days being caused by fractures. The cost for out- and inpatient acute treatment was approximately USD 4700 (SEK 33,000) per injured. The results merit an interest for this target group; bicycle injuries among older adults are costly both for the individual and the medical sector. Injury mitigation strategies focused on the needs of this group are probably as well motivated as those focused on older car drivers.  相似文献   
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