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461.
A sacrococcygeal teratoma was suspected by ultrasound examination at 24 weeks gestation. The amniotic fluid alphafetoprotein was markedly elevated, as was maternal serum AFP. Gel electrophoresis of amniotic fluid showed an acetylcholinesterase band. Labour began at 25 weeks gestation and the chromosomally normal male fetus was found to have a sacrococcygeal teratoma equal to three-quarters of the weight of the fetus.  相似文献   
462.
Trail, Canada has been the site of a large lead/zinc smelting facility since 1916. In mid 1990, the Trail Community Lead Task Force was established and given responsibility for developing a strategy to reduce children's blood lead levels. With funding from the provincial government, the smelting company and the municipal government, the Task Force has carried out blood lead screening, case management, community education, exposure pathways modelling and remediation trials. The decline in children's blood lead levels appeared to accelerate following the implementation of these programmes. The average blood lead in Trail children aged 6–72 months fell 14% from the autumn of 1991 to autumn of 1992, whereas for the previous 16 years, the average annual decline had been about 4%. In subsequent years, blood lead levels have appeared to plateau. Throughout the 5-year history of the Task Force, its members have demonstrated a strong sense of common purpose and have worked co-operatively to reach consensus on most issues.  相似文献   
463.
High levels of fluoride (beyond 1.5 ppm) in ground water as source of drinking water are common in many parts of Andhra Pradesh, India, causing fluorosis. The study carried out in endemic Nalgonda District, Andhra Pradesh, has indicated that the fluoride-rich ground water present in the wells located down stream and close to the surface water bodies is getting diluted by the low-fluoride surface water. Encouraged by this result, check dams were constructed upstream of the identified marginally high fluoride bearing ground water zones in Anantapur District to reduce fluoride levels as an alternate solution for safe drinking water.In this paper, an attempt is made to study the utility and effect of these check dams in dilution of fluoride concentration in drinking water and its resultant impact on the health aspects of certain villagers of Anantapur District through the analysis of their blood serum and urine. Ground water samples from three fluoride-affected villages, blood and urine of males and females from the same villages were collected and analyzed for fluoride using ion selective electrode method. The results indicated that the fluoride levels in blood serum and urine of males in the age group of 5–11 years are found to be the highest. The concentration of fluoride in ground water is directly proportional to the concentration of fluoride in blood serum and urine. The concentration of fluoride in ground water with depth of the aquifer is a function of lithology, amount and duration of rainfall, rate of infiltration, level of ground water exploitation in the area etc. The construction of check dams upstream of the identified marginally high fluoride waters will not only cause additional recharge of ground water but also reduces the fluoride concentration eventually improving the health of the villagers.  相似文献   
464.
Enrichment of lead in respirable suspended particulate matter (RSPM) and exposure of human blood to particulate lead in traffic environment were investigated. Samples of RSPM, non-respirable suspended particulate matter (NRSPM) and total suspended particulate matter (TSPM) were collected in 10 sampling sites located on National Highway No. 6, Durg–Bhilai section of Chhattisgarh State of India. Forty blood samples, out of which 20 of highway traffic personnel with chronic exposure and other 20 of general population who were residing more than 10 km away from the National Highway, were collected. Samples of particulate matter were weighed and analysed for particulate lead. Results have shown a higher concentration of average RSPM and TSPM in all the sampling sites compared to the Indian permissible limits. Geometric mean of lead levels was found in the range of 0.880–1.414 µg/m3 (TSPM) in the study sites. Concentrations of lead in RSPM have shown a higher enrichment (range 2.645–3.171) relative to NRSPM. Blood lead levels in traffic personnel and general population were found in the range of 56.70–101.17 µg/dL and 7.92–31.22 µg/dL, respectively.  相似文献   
465.
The background levels of lead in Jamaica in soils and sediments, estimated at 37 mg kg–1, are relatively high compared with world averages. Several areas have values in excess of this due to mineralisation and pollution. One such is the residential Hope Flats/Kintyre area in which levels of lead up to 2.5% are found in the soils and up to 8 g kg–1 in the water of the nearby Hope River. The blood lead levels of a sample of children were in the range 5.7–57 g dl–1. The high lead levels suggest a potential health risk, particularly for the children. This can be minimised by programmes which include community education, case management and abatement to reduce the lead exposure.  相似文献   
466.
本试验研究了添加糖萜素对早期断奶仔猪血液生化指标及免疫机能的影响.选用21日龄左右健康无病、体重基本一致的杜长大猪进行饲喂试验,随机分为5组,每组3个重复,每重复8头猪,自由采食和自由饮水.试验设计为:第Ⅰ组为对照组,第Ⅱ、Ⅲ组在每公斤基础日粮中分别加入250rag、500rag糖萜素,第Ⅳ、Ⅴ组在每公斤基础日粮中分别加入250mg糖萜素+4mg黄霉素、4mg黄霉素,结果表明:①糖萜素与黄霉素单用及联用均能提高仔猪血清中’IP、GLO和G/A的值。而以第Ⅲ组的效果最好.②糖萜素与黄霉素单用及联用均能显著提高血清IgA(P〈0.01),与对照组相比分别提高43.21%、104.89%、73.21%、27.74%,IgG(P〈0.05)而对IgM无显著影响(P〉0.05),CD3均有一定程度的提高(P〉0.05).③血清中BUN试验组比对照组分别提高2.67%、2.96%、2.8l%、2.52%,各试验组间差异不显著(P〉0.05),对血清中GLU影响不大.④血清中GOT、GPT、ALK(均有所提高,但差异不显著(P〉0.05),而LDH活性与对照组相比分别下降2.7l%、4.02%、2.96%、1.65%,糖萜素与黄霉素的联合应用表现一定的协同作用,但效果不显著.  相似文献   
467.
杜仲叶.粉对肉鸡生产性能及血液生化指标的影响   总被引:3,自引:0,他引:3  
为探明杜仲叶粉对肉鸡生产性能及血液生化指标的影响,按0.5%、1%、1.5%、2%的比例在肉鸡的基础日粮中添加杜仲叶粉,以不添加杜仲叶粉作为对照,经60天饲养试验期后,对各组鸡的日增重、饲料报酬(增重与耗料之比)、胴体品质及血液生化指标进行检测,结果表明:杜仲叶粉能提高肉鸡饲料报酬,改善胴体品质,改善血液生化指标.  相似文献   
468.
Cytogenetic data from the United States NICHD collaborative study of chorionic villus sampling (CVS) were used to evaluate the clinical significance of chorionic mosaicism. The 10 754 patients with normal cytogenetic results were compared wtih 108 patients (1.0 per cent) with placental mosaicism and 181 patients (1.6 per cent) with pseudomosaicism. Of the pregnancies intended to continue, the pregnancy loss rate was significantly greater in patients with placental mosaicism than in the cytogenetically normal cohort (8.6 vs. 3.4 per cent, p <0.05). However, there was no difference in the frequencies of abruptio placenta, preterm labour or delivery, small-for-gestational-age newborns, pregnancy-induced hypertension, or neonates with Apgar scores less than 7.  相似文献   
469.
In 2103 consecutive diagnostic chorionic villus samples, examined in a 4-year period in our clinical genetics unit, 26 samples (1.2 per cent) presented chromosomal mosaicism in the direct and/or long-term culture preparations. Only once (46,XX/47,XX,+9) was the mosaicism confirmed in the fetus. In the cytogenetic follow-up studies of the remaining 25 pregnancies, in no cases could the aberration be confirmed in amniotic fluid or fetal tissue. One patient requested a termination after the CVS result. Of the remaining 24 pregnancies, four (16.7 per cent) ended in a spontaneous abortion. These findings suggest an association between placental mosaicism and fetal loss.  相似文献   
470.
Fetal supraventricular tachycardia (SVT) can be successfully treated transplacentally, but in cases where fetal hydrops develops there is considerable morbidity and mortality. The present study was carried out to establish whether the introduction of flecainide altered obstetric management and fetal outcome. A retrospective analysis took place of 51 singleton pregnancies which were referred to the division of prenatal diagnosis because of fetal tachycardia between 1982 and 1993. SVT was documented in 50 out of 51 fetuses, one of which displayed a combination of extensive rhabdomyomas and severe hydrops and died shortly after referral. In the other fetus ventricular tachycardia was diagnosed. Of the remaining 49 fetuses, 14 did not receive any prenatal treatment, but nine needed postnatal treatment. Transplacental treatment of SVT took place in 35 fetuses, of which 22 presented without hydrops and 13 with hydrops. These subsets differed significantly with respect to restoration of normal sinus rhythm (73% vs. 30%; p<0.001) and mortality (0% vs. 46%; p<0.001). Digoxin was effective in restoring sinus rhythm in 55 per cent of the non-hydropic fetuses but in only eight per cent of the hydropic fetuses. Flecainide was effective in restoring sinus rhythm in all non-hydropic fetuses where digoxin treatment failed, and in 43 per cent of hydropic fetuses. Administration of flecainide resulted in a significantly reduced mortality (p<0.001) compared with digoxin treatment. No adverse effects were seen. Postnatal anti-arrhythmic treatment was necessary in 23 infants. Treatment could be withdrawn within one year in all cases but one.  相似文献   
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