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331.
332.
Efremova KO Volodin IA Volodina EV Frey R Lapshina EN Soldatova NV 《Die Naturwissenschaften》2011,98(11):919-931
In goitred gazelles (Gazella subgutturosa), sexual dimorphism of larynx size and position is reminiscent of the case in humans, suggesting shared features of vocal
ontogenesis in both species. This study investigates the ontogeny of nasal and oral calls in 23 (10 male and 13 female) individually
identified goitred gazelles from shortly after birth up to adolescence. The fundamental frequency (f0) and formants were measured
as the acoustic correlates of the developing sexual dimorphism. Settings for LPC analysis of formants were based on anatomical
dissections of 5 specimens. Along ontogenesis, compared to females, male f0 was consistently lower both in oral and nasal
calls and male formants were lower in oral calls, whereas the first two formants of nasal calls did not differ between sexes.
In goitred gazelles, significant sex differences in f0 and formants appeared as early as the second week of life, while in
humans they emerge only before puberty. This result suggests different pathways of vocal ontogenesis in the goitred gazelles
and in humans. 相似文献
333.
Ivonne Bedei Tascha Gehrke Karl-Philipp Gloning Matthias Meyer-Wittkopf Daria Willner Martin Krapp Alexander Scharf Jan Degenhardt Kai-Sven Heling Peter Kozlowski Kathrin Trautmann Kai M. Jahns Annegret Geipel Jan-Erik Baumüller Lucas Wilhelm Ingo Gottschalk Andreas Schröer Alexander Graf Aline Wolter Johanna Schenk Axel Weber Ignatia B. Van den Veyver Roland Axt-Fliedner 《黑龙江环境通报》2023,43(2):192-206
Objective
We aimed to investigate how the presence of fetal anomalies and different X chromosome variants influences Cell-free DNA (cfDNA) screening results for monosomy X.Methods
From a multicenter retrospective survey on 673 pregnancies with prenatally suspected or confirmed Turner syndrome, we analyzed the subgroup for which prenatal cfDNA screening and karyotype results were available. A cfDNA screening result was defined as true positive (TP) when confirmatory testing showed 45,X or an X-chromosome variant.Results
We had cfDNA results, karyotype, and phenotype data for 55 pregnancies. cfDNA results were high risk for monosomy X in 48/55, of which 23 were TP and 25 were false positive (FP). 32/48 high-risk cfDNA cases did not show fetal anomalies. Of these, 7 were TP. All were X-chromosome variants. All 16 fetuses with high-risk cfDNA result and ultrasound anomalies were TP. Of fetuses with abnormalities, those with 45,X more often had fetal hydrops/cystic hygroma, whereas those with “variant” karyotypes had different anomalies.Conclusion
Both, 45,X or X-chromosome variants can be detected after a high-risk cfDNA result for monosomy X. When there are fetal anomalies, the result is more likely a TP. In the absence of fetal anomalies, it is most often an FP or X-chromosome variant. 相似文献334.
Schmidt G Pesch R Schröder W Conrad A Kolossa-Gehring M Feigenspan S Dobler L Wiesmüller GA Birke M Utermann J 《Environmental geochemistry and health》2011,33(4):399-408
This study aimed at statistically investigating the association between the internal exposure of children and young adults
to uranium (U) and epidemiologically relevant external determinants of exposure. The investigation was performed with data
from two studies within the framework of the German health-related environmental monitoring program: The German Environmental Survey for Children (GerES IV) conducted by the Federal Environment Agency (Umweltbundesamt) with data on 1,780 children 3–14 years of age and their home environment and the German Environmental Specimen Bank (ESB, section: human specimens) with data on 2,253 students 20–29 years of age. Both studies provided data on the U levels in human urine for all probands.
GerES IV furthermore provided an extensive environmental and demographic database on, e.g., U levels in drinking water. The
data from GerES IV and ESB were linked by GIS to spatially relevant exposure information, including background values of U
in stream sediments and in upper and lower soils, U levels in mosses and particulate matter in the lower atmosphere, precipitation
and elevation as well as forest density. Bivariate correlation analysis and two decision tree models showed moderate but significant
associations between U in human urine and U levels in drinking water, stream sediments and upper and lower soils. Future investigations
considering additional epidemiologically relevant data sets may differentiate the results. Furthermore, the sample design
of future environmental epidemiology studies should take the spatial evaluation of the data into greater account. 相似文献
335.
Ali Aasim M. Higgins Christopher P. Alarif Walied M. Al-Lihaibi Sultan S. Ghandourah Mohammed Kallenborn Roland 《Environmental science and pollution research international》2021,28(3):2791-2803
Environmental Science and Pollution Research - Per- and polyfluoroalkyl substances (PFASs) are today considered important constituents of the continuously growing substance group of persistent... 相似文献
336.
Rachowicz LJ Knapp RA Morgan JA Stice MJ Vredenburg VT Parker JM Briggs CJ 《Ecology》2006,87(7):1671-1683
A newly discovered infectious disease of amphibians, chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis, is implicated in population declines and possible extinctions throughout the world. The purpose of our study was to examine the effects of B. dendrobatidis on the mountain yellow-legged frog (Rana muscosa) in the Sierra Nevada of California (USA). We (1) quantified the prevalence and incidence of B. dendrobatidis through repeat surveys of several hundred R. muscosa populations in the southern Sierra Nevada; (2) described the population-level effects of B. dendrobatidis on R. muscosa population abundance; and (3) compared the mortality rates of infected and uninfected R. muscosa individuals from pre- through post-metamorphosis using both laboratory and field experiments. Mouthpart inspections conducted in 144 and 132 R. muscosa populations in 2003 and 2004, respectively, indicated that 19% of R. muscosa populations in both years showed indications of chytridiomycosis. Sixteen percent of populations that were uninfected in 2003 became infected by 2004. Rana muscosa population sizes were reduced by an average of 88% following B. dendrobatidis outbreaks at six sites, but at seven B. dendrobatidis-negative sites, R. muscosa population sizes increased by an average of 45% over the same time period. In the laboratory, all infected R. muscosa developed fatal chytridiomycosis after metamorphosis, while all uninfected individuals remained healthy. In the field experiment in which R. muscosa tadpoles were caged at infected and uninfected sites, 96% of the individuals that metamorphosed at infected sites died vs. 5% at the uninfected sites. These studies indicate that chytridiomycosis causes high mortality in post-metamorphic R. muscosa, that this emerging disease is the proximate cause of numerous observed R. muscosa population declines, and that the disease threatens this species with extirpation at numerous sites in California's Sierra Nevada. 相似文献
337.
In recent years, pyrolysis processes have become technologies developed to industrial scale and discussed as alternatives to the existing waste combustion technology. However, little information is published regarding PCDD/F formation characteristics during pyrolysis processes. Two common shredder fractions – industrial light shredder (ILS) and refrigerators (REF) – both with high chlorine and copper content were pyrolysed for this pyrolysis study using a pilot plant with a capacity of 100 kg/h. At oxygen concentrations below 2% and temperatures between 430°C and 470°C, considerable amounts of PCDD/F were formed during the pyrolysis. More than 90% of total TEQ was found in the oil fraction (gas phase). The PCDD/PCDF ratio and the homologue pattern differed significantly from those formed during waste incineration. Considering mono- to octachlorinated congeners, up to 400 times more PCDF were formed compared to PCDD. For the investigated pyrolysis conditions, the formation of low chlorinated congeners was highly favoured. The distribution of TEQ within the individual congeners were very similar in all investigated runs. More than 80% of total TEQ stem from 2,3,7,8-substituted T4CDF and P5CDF. The isomer pattern, however, did not show significant differences compared to the common waste incineration pattern suggesting that the basic formation routes are similar. 相似文献
338.
Winfried Schröder Hubert Bast Roland Pesch Gunther Schmidt Ellen Kiel 《Environmental Sciences Europe》2007,19(2):115-122