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31.
We present a case of esophageal and ileal duplications at 18 weeks of gestation. Transabdominal ultrasonography of the fetus showed multiple cystic masses of 12 to 17 mm in diameter and continuity with each other in the abdomen and a unilocular cystic mass of 15 mm in diameter in the posterior mediastinum. The cystic mass filled the abdominal cavity with signs of intestinal obstruction. The thoracic cystic mass was tubular, sausage-shaped and behind the heart, which was displaced to the antero-lateral wall of the chest. Amniocentesis revealed a normal fetal karyotype 46,XY. Peristaltic movements in the abdominal cystic structure at 30 weeks of gestation suggested dilated intestinal loops. Follow-up ultrasound examinations showed polyhydramnios with amniotic fluid index of 30 cm and gradual enlargement of the cystic structures to 50 mm in the abdomen and 30 mm in the posterior mediastinum at 38 weeks of gestation. A male infant weighing 3900 g was delivered. Postnatal ultrasonographic examination and the findings of magnetic resonance imaging also suggested enteric duplication cysts. Prenatal diagnosis allowed prompt neonatal evaluation and surgical treatment of the esophageal and the ileal duplications, which was confirmed by pathological examination. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
32.
Environmental Science and Pollution Research - In this study, the performance of the Sequential Gaussian Simulation (SGS) approach was studied with the aim of accurately determining local health...  相似文献   
33.
Environmental Science and Pollution Research - In the present study, the concentration levels of heavy metals such as Mn, Fe, Ni, Cu, Zn, Cr, and Pb in sediment samples collected from 16 sampling...  相似文献   
34.
Picloram (4-amino-3,5,6-trichloropicolinic acid) is a liquid auxinic herbicide used to control broad-leaved weeds. Picloram is representing a possible hazard to ecosystems and human health. Therefore, in this study, DNA methylation changes and DNA damage levels in Phaseolus vulgaris exposed to picloram, as well as whether humic acid (HA) has preventive effects on these changes were investigated. Random amplified polymorphic DNA (RAPD) techniques were used for identification of DNA damage and coupled restriction enzyme digestion-random amplification (CRED-RA) techniques were used to detect the changed pattern of DNA methylation. According to the obtained results, picloram (5, 10, 20, and 40 mg/l) caused DNA damage profile changes (RAPDs) increasing, DNA hypomethylation and genomic template stability (GTS) decreasing. On the other hand, different concentrations of applied HA (2, 4, 6, 8, and 10%) reduced hazardous effects of picloram. The results of the experiment have explicitly indicated that HAs could be an alternative for reducing genetic damage in plants. In addition to the alleviate effects of humic acid on genetic damage, its epigenetic effect is hypomethylation.  相似文献   
35.

This study involves the monitoring of organic pollutants using transplanted mussels (Mytilus galloprovincialis) as bioindicator organisms and semipermeable membrane devices (SPMDs) as passive samplers. Mussels and SPMDs were deployed to marinas, shipyards and shipbreaking yards on the coastal area of Turkey and retrieved after 60 days. Polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and organochlorine pesticide (OCP) compounds were analysed with high-resolution GC-MS. Total PAH concentrations in SPMDs and mussels ranged from 200 to 4740 ng g sampler?1 and from 7.0 to 1130 ng g?1 in wet weight (ww). PCB and OCP concentrations in SPMDs changed between 0.04–200 and 4.0–26 ng g sampler?1, respectively. The highest PCB (190 ng g?1 ww) and OCP (200 ng g?1 ww) concentrations in mussels were measured at shipyard stations. A strong correlation was observed between the PAH and PCB concentrations in SPMDs and mussels. Enzyme assays (acetylcholinesterase, ethoxyresorufin-O-deethylase, glutathione S-transferase, glutathion reductase and carboxylesterase activities) were performed as biomarkers to reveal the effects of pollution on the mussels. There was no clear relationship found between the enzyme levels and the pollutant concentrations in mussels. Integrated biomarker responses were calculated to interpret the overall effect of pollutants.

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36.
Grabens are formed under the influence of extensional forces in a normal fault system. The Gulf of Gökova is an active graben located in SW Turkey. Active grabens such as the Gökova enclose highly faulted rocky coasts. Despite the existence of these rocky coasts, examination of google earth images, field studies, DEM analysis and previous studies in the Gulf of Gökova graben revealed that there could be different types of coasts in the region. In this study the factors causing the occurrence and potential environmental effects of the diverse coast types are evaluated. By using the Fairbridge (2004) coastal classification system, the coast types identified in the Gulf of Gökova graben can be classified as; A. Soft-less consolidated-erodible; A1: relatively Insoluble: detrital and loose beach, A2: soluble: beachrock and eolinite B. hard-cliffed-rocky, B1: longevity of hard-rock coast and B2: fault controlled cliffs. The percentages of these classes generally decreased from B1 (79%), A1 (12.4%), B2 (8.3%) and A2 (0.3%) in the study area. As a result of longshore currents, A1-type coasts usually develop as large plain adjacent streams and also in pocket beaches as narrow-long strips near rocky coasts. A2 type is observed in one location within the Gökova region, possibly due to local environmental conditions. However, B1 type developed in peridotites, cherty limestone and cliffs probably because of the active fault system and where the fault plane cut the coast, B2 type occurred. Possible threats to the Gökova region can be attributed to sea level rise owing to tectonism and global warming. It is anticipated that inundation, coastal erosion and salt water intrusion may also affect it.  相似文献   
37.
Red sea breams were kept at 20°C without food at 3 salinities (full sea water, 950 mOsm kg-1; 2/3 sea water, 640 mOsm kg-1; 1/3 sea water, 330 mOsm kg-1). In fish adapted to all 3 salinities, starvation resulted in marked decline of plasma FFA and -hydroxybutyrate and liver glycogen levels but plasma glucose and lactate concentrations were maintained. These findings suggest that with the onset of starvation, enhanced hepatic glycogenolysis and decreased fat utilization occurred. Fish, adapted to full and 2/3 sea water, could not survive for more than 19 d without food. However, fish adapted to 1/3 sea water could tolerate 27 d of starvation. Enhanced survival during starvation in 1/3 sea water was observed to be associated with maintenance of plasma protein and elevation of hepatic glucose-6-phosphate dehydrogenase activity. It is suggested that sea breams be transferred to an iso-osmotic medium whenever the threat of starvation prevails, but this suggestion has yet to be evaluated in economic terms.Please communicate with Dr. Norman Y. S. Woo  相似文献   
38.
In this study, some heavy metal concentrations (Pb, Zn, Fe, Cr, Cu), suspended sediment, chemical oxygen demand (COD), biological oxygen demand (BOD), cyanide, phenol, fecal coliform and total coliform water parameters were determined in the streams (Kucuk Melen, Asarsuyu, Ugursuyu, Buyuk Melen and Aksu) of Buyuk Melen Watershed that provides drinking water to Istanbul in Western Black Sea Region of Turkey. Measurements of water quality parameters were done monthly in eleven separate stations (4 in Kucuk Melen Stream, 1 in Asarsuyu Stream, 1 in Ugur Stream, 1 in Aksu Stream and 4 in Buyuk Melen Stream) from August 2001 to August 2002. The seasonal changes in water quality parameters were evaluated statistically. The results, the parameters, COD, BOD, Pb, Zn, Fe, Cr, Cu, cyanide, fecal coliform, total coliform and suspended sediment showed significant differences among seasons and streams (ANOVA; P <0.05). According to Turkish Standarts (TS) 266, European Union (EU) and World Health Organization (WHO) criteria, the maximum values of each parameter in streams within the Buyuk Melen watershed are recorded and evaluated in this study.  相似文献   
39.
Abstract

An olive tree was treated twice in the field with 14C‐dimethoate (237.7 (μCi, 2.4 g) and 14C residues were determined in the olive fruits at harvest. The fruits were crushed and pressed to extract the crude oil, then refined by neutralization, bleaching and deodorization. The crude oil contained 14.1% of the total 14C in the olive fruits. Neutralization resulted in a reduction of 14C by about 50% of the total 14C residues in oil. Bleaching and deodorization processes further reduced the 14C residues and the refined oil contained 31.6% (which corresponds to 4.4% of I4C residues of the total 14C in olive fruits) of the total 14C in the crude oil. Industrially extracted crude oil was fortified with 14C‐dimethoate at 1.8 mg kg‐1 (0.02 μCi) level and subjected to the same refining process. A sharp decrease in the amount of 14C was observed by neutralization and the amount of 14C remaining in the refined oil was about 7.3% of the total l4C in the crude fortified oil. The data suggest that the 14C residues in the aged and the fortified oil amples were not of the same nature. The terminal 14C residue in the refined oil obtained from the field experiment did not contain dimethoate and/or its oxon.  相似文献   
40.
In recent years, a number of studies have clearly pointed out the nutritional benefits of fish consumption. However, some concerns about potential health risks derived from contaminants found in fish have also been raised. Therefore, balancing adequately the risks and benefits of fish consumption is currently a health key issue. As tuna fish represents a large part of the traditional food in some countries, the possible impact of tuna fish consumption on public health was investigated. Hepatic damages following consumption of tuna fish white (ordinary) or red (dark) muscle were evaluated in rat. Under our experimental conditions, feeding the animals for 60?days with white or, more markedly, red tuna meat resulted in 1) an elevated uric acid level in blood, 2) an accumulation of lead in liver, 3) an atrophy of liver, 4) an increase in plasma aspartate aminotransferase and alanine aminotransferase activities, and 5) an oxidative stress in liver including an increased level of lipids peroxidation and enhanced activities of superoxide dismutase, catalase and glutathione peroxidase. In addition, liver histology revealed several abnormalities. These alterations could be attributed to both lead accumulation and high purine levels in tuna meat. We conclude that attention should be paid to a possible health impact of frequent and important consumption of tuna fish meat, especially the dark one.  相似文献   
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