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471.
We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs), and non-dioxin-like PCBs in paired samples of blood and breast milk collected from 67 secundiparas in Sapporo City, Japan, and combined this data with those of the 30 secundiparas previously measured. The arithmetic mean total toxic equivalents (TEQ-WHO) concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk of the 97 secundiparous subjects were 3.0-23 (mean: 13, median: 14) and 2.7-20 (mean: 8.6, median: 8.5) pg TEQ g−1 lipid, respectively. The sums of the concentrations of 56 non-dioxin-like PCB congeners that were measured in the subjects’ blood and breast milk were 16-326 (mean: 107, median: 100) and 12-252 (mean: 73, median: 67) ng g−1 lipid, respectively. The partitioning ratios of individual congeners of PCDDs, PCDFs, dioxin-like PCBs, and non-dioxin-like PCBs from blood to breast milk in secundiparas were almost the same as those of primiparas that have been recently reported, suggesting that the partitioning ratios of these compounds from maternal blood to breast milk in women is little affected by delivery. Furthermore, the partition of PCB congeners with chlorine at the 2-, 3-, 4′-, and 5-positions or the 2-, 4-, 4′-, and 5-positions of the biphenyl ring from the blood to the breast milk tended to occur at a higher level than that of other congeners. In particular, the levels of tetraCB-74 and hexaCB-146 in the breast milk for both primiparous and secundiparous mothers were slightly higher than those in the blood.  相似文献   
472.
473.
Over a five-year period in the West Midlands there were 34 pregnancies to women who were possible carriers for Duchenne muscular dystrophy and who were known to the Department of Clinical Genetics. Fetal sexing was performed in only ten of 26 pregnancies to women of high or moderate risk, and of the five male fetuses discovered, only two were aborted. Overall, the 34 pregnancies resulted in one miscarriage, 14 males (of whom two were aborted and two were affected) and 19 females. Information was also obtained on five further possible carriers who were ascertained solely because they had an amniocentesis. These five pregnancies led to the birth of one affected male and to the termination of one male fetus.  相似文献   
474.
通过对乌鲁木齐市大气中CO含量以及居民血液中HbCO的调查,并对其二者的相关性研究认为人体中HbCO含量随大气中CO浓度升高而增加,吸烟引起的人体中HbCO水平比暴露于大气中的CO所引起的HbCO水平更高得多,吸烟污染更为严重。  相似文献   
475.
A direct and simple method for the clinic muti-element determination of human blood sample by Zeeman graphite furnace atomic absorption spectropho-tometry is reported. No pretreatment of the sample is necessary other than simple dilution of the sample with aqueous solution of Triton X-100. The detection limits of the elements investigated fall in the range of 0.1- 4.4 μg/L with a relative standard deviation ranging from 1.6 for zinc to 3.73% for lead. Micro liters of samples are sufficient for the determination of each element.  相似文献   
476.
477.
正Imagine if a group of toxic substances that increase oxidative stress and disrupt glucose and lipid metabolism have been broadly used worldwide for applications such as repellent,food packaging,and non-stick frying pan coatings.Now imagine if some of these substances have half-lives as long as 3-8 years.This is an environmental reality that has come to light with perfluoroalkyl and polyfluoroalkyl substances(PFASs)–high  相似文献   
478.
Fetal death occurs in 15% of clinically recognized pregnancies. Cytogenetic abnormalities are present in 50% of spontaneous abortions (fetal deaths < 20 weeks) whereas the rate is 6% to 13% for stillbirths (fetal deaths ≥ 20 weeks). Microarray has been demonstrated to increase the diagnosis of genetic abnormalities by providing coverage of the entire genome at a higher density, detecting as small as 50 to 100 kb deletions or duplications, known as copy number changes. Microarray is particularly suited for evaluation of fetal death because DNA can still be analyzed in macerated fetuses and nonviable tissue, two situations where culturing and karyotyping is known to have low yield. Microarray has already proven successful in providing additional genetic information beyond karyotype in spontaneous abortion. The few studies on the use of microarray in stillbirth evaluation have been promising, demonstrating an increase in the diagnosis of clinically relevant genetic abnormalities when compared with karyotype. As the cost and technology improve, microarray may ultimately become the first line screen for genetic abnormalities in stillbirth. The accurate diagnosis of a genetic abnormality as the cause for fetal death may provide closure for families, prevent unnecessary treatments, and enable clinicians to more accurately counsel and manage subsequent pregnancies. © 2012 John Wiley & Sons, Ltd.  相似文献   
479.
It is widely known that human exposure to mercury vapor can cause neurological and neuropsychological deterioration. We have investigated if a population of Chilean artisanal gold-mining workers heavily exposed to elemental mercury (Hg0) display neurological and neuropsychological impairment. Male volunteers occupationally exposed to Hg0 (“gold miners”, n = 35) were recruited and compared with a group of unexposed workers (n = 40). Blood specimens were obtained from both groups for total mercury quantification. Upon neurological examination, 71% of the “gold miners” group showed abnormalities expressed as frontal impairment, tremor, or simultaneously frontal impairment, parkinsonism, and pyramidal syndrome. In contrast, only 16% of the individuals in the control group displayed neurological abnormalities. The “gold miners” group also showed impairment of the neuropsychological performance and the distribution of abnormal scores for almost all the neuropsychological tests applied was significantly higher in this group compared to the control group. Educational level, alcohol intake, and smoking habits did not influence the outcome of the neurological or neuropsychological examinations. Finally, despite that the higher blood mercury concentrations were found in the “gold miners” group, they were not significantly different from the values obtained in the control group.  相似文献   
480.
目的 探讨扼子黄色素对高脂膳食小鼠血脂水平的影响.方法 将30只小白鼠随机分为三个组:对照组,高脂模型+扼子黄色素组、高脂模型+柠檬黄组(0.2、0.5 mg/g体重),喂养180 d后,眼球采血测定血清TC、TG、MDA含量.结果 扼子黄色素组血清MDA、TC、TG升高幅度较高脂模型+柠檬黄组明显减少.结论 扼子黄色素对高脂膳食致血脂升高有阻抑作用.表2,参6.  相似文献   
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