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611.
Susan M. Haig Jeffrey R. Walters Jonathan H. Plissner 《Behavioral ecology and sociobiology》1994,34(4):295-303
We examined the genetic relationship among putative parents, offspring, and helpers in 224 red-cock-aded woodpeckers (Picoides borealis) from the Sandhills of North Carolina. Comparison of DNA similarity with a pedigree constructed from 3,823 individually-marked birds observed from 1979 to 1992 provided verification of observed relatedness in the sampled population (R
2 = 0.87, df = 14, P < 0.001). In this population, breeding pairs may or may not have helpers, most of which are males that remain on their natal territory. Our sample included helpers assisting their parents, helpers assisting a related male and an unrelated female, and helpers assisting an unrelated pair. Band by band comparison and examination of similarity among DNA profiles indicated that all offspring from non-helped nests were sired by their putative parents (n = 28 families). Similarly, all but one offspring in helped nests were also sired by their putative parents (n = 16 families). In the exceptional case, the offspring evidently was sired by a male external to the group. Analysis of similarity values supported the conclusion that matings by helpers or extra-group males are rare or non-existent. Our results indicate that in this species advantages gained by individuals remaining on their natal territories as helpers do not generally include siring offspring.
Correspondence to: S. Haig 相似文献
612.
DNA加合物8-氢基脱氧鸟苷特性研究 总被引:4,自引:0,他引:4
作为DNA氧化损伤的生物学标志物,8-羟基脱氧鸟苷(8-OH-dG)的特性研究,对稳定、灵敏、准确地定量8-OH-dG,进而研究有毒化学物质对生物体内的氧化损伤很重要,该文研究了氧化损伤DNA中8-OH-dG的分析、水解、储存、稳定性等方面的问题,采用Fenton型产羟自由基系统如螯合剂Fe^2 -H2O2为氧化源,与脱氧鸟苷和小牛胸腺DNA反应,生成的8-OH-dG用高压液相色谱-电化学法检测,并对8-OH-dG的分析条件进行优化,该法最低检出限为32fmol,比光学吸收法高2~3个数量级,线性范围可高达4个数量级,从0.32pmol到3.2nmol,相关系数0.9996。并对酶水解DNA的条件、储存酸度、中性偏酸的缓冲液中损失较少,其形成与所处介质环境有关,在氧化源存在或有氧环境中一定时间内有积累作用,添加抗氧化剂等干预措施后,能灵敏而稳定地对DNA中的8-OH-dG进行测定。 相似文献
613.
Maria Paola Iampieri Rita Mingarelli Eric Le Guern Giuseppe Novelli Professor Bruno Dallapiccola 《黑龙江环境通报》1994,14(4):285-289
Five pregnancies at risk for X-linked retinitis pigmentosa (RP) have been monitored by first-trimester prenatal diagnosis using DNA markers flanking the RP2 and RP3 loci. Three affected and two unaffected fetuses, including a female carrying a wild-type genotype, were predicted on the basis of marker segregation and estimation of the recombination fraction. 相似文献
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Tobias J. Legler Zhong Liu Ariadni Mavrou Kirstin Finning Ilona Hromadnikova Silvia Galbiati Cathy Meaney Maj A. Hultén Francesco Crea Martin L. Olsson Deborah G. Maddocks Dorothy Huang Sylvia Armstrong Fisher Markus Sprenger-Haussels Aicha Ait Soussan C. Ellen van der Schoot 《黑龙江环境通报》2007,27(9):824-829
Objective Cell free foetal DNA (cff DNA) extracted from maternal plasma is now recognized as a potential source for prenatal diagnosis but the methodology is currently not well standardized. To evaluate different manual and automated DNA extraction methods with a view to developing standards, an International Workshop was performed. Methods Three plasma pools from RhD-negative pregnant women, a DNA standard, real-time-PCR protocol, primers and probes for RHD were sent to 12 laboratories and also to one company (Qiagen, Hilden, Germany). In pre-tests, pool 3 showed a low cff DNA concentration, pool 1 showed a higher concentration and pool 2 an intermediate concentration. Results The QIAamp DSP Virus Kit, the High Pure PCR Template Preparation Kit, an in-house protocol using the QIAamp DNA Blood Mini Kit, the CST genomic DNA purification kit, the Magna Pure LC, the MDx, the M48, the EZ1 and an in-house protocol using magnetic beads for manual and automated extraction were the methods that were able to reliably detect foetal RHD. The best results were obtained with the QIAamp DSP Virus Kit. The QIAamp DNA Blood Mini Kit showed very comparable results in laboratories that followed the manufacturer's protocol and started with ≥ 500 µL plasma. One participant using the QIAamp DNA Blood Midi Kit failed to detect reliably RHD in pool 3. Conclusions This workshop initiated a standardization process for extraction of cff DNA in maternal plasma. The highest yield was obtained by the QIAamp DSP Virus Kit, a result that will be evaluated in more detail in future studies. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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The mating frequency of queens was estimated for eight attine ant species, Myrmicocrypta ednaella, Apterostigma mayri, Cyphomyrmex costatus, C. rimosus (four lower attines), Trachymyrmex isthmicus, Serico-myrmex amabalis, Acromyrmex octospinosus and Atta colombica (four higher attines), and correlated to colony size, worker polyethism, and sex ratio. Mating frequency was calculated from
within-colony relatedness estimated by CAP-PCR DNA fingerprinting. Most queens of lower attines and T. isthmicus mated with only one male, while those of the three higher attines mated with multiple males. Mating frequency was positively
correlated with colony size. Polyethism among workers was dependent on worker age in lower attines but on body size in higher
attines, suggesting some correlation between mating frequency (i.e., within-colony gene diversity) and caste complexity. The
sex ratio was biased toward females in species where the mating frequency equaled one, but toward males in species where the
mating frequency was greater than two. Changing in nest site from ground surface to deep underground may have facilitated
the evolution of large colony size in Attini, and this may have resulted in the evolution of polyandry (a queen mates with
multiple males). With the evolution of polyandry in higher attines, Atta and Acromyrmex in particular have generated high genetic diversity within their colonies and complex social structures.
Received: 26 October 1999 / Revised: 25 May 2000 / Accepted: 24 June 2000 相似文献