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951.
宁夏是我国最重要的枸杞Lycium chinense Miller生产基地,蚜虫是危害枸杞的重要害虫。多年来枸杞蚜虫一直作为一个未定名物种使用Aphis sp.。2015年作者对宁夏危害枸杞的蚜虫进行了标本采集,经中国科学院动物研究所乔格侠研究员鉴定确认是常见的3种蚜虫,分别是棉蚜Aphis gossypii Glover、桃蚜Myzus persicae(Sulzer)和豆蚜Aphis craccivora Koch。本文提供了它们的鉴定检索表和简要形态特征描述、寄主植物和分布情况。 相似文献
952.
A mass stranding of seven Longman's beaked whales (Indopacetus pacificus) in New Caledonia,South Pacific
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Claire Garrigue Marc Oremus Rémi Dodémont Paco Bustamante Olivier Kwiatek Geneviève Libeau Christina Lockyer Jean Christophe Vivier Merel L. Dalebout 《Marine Mammal Science》2016,32(3):884-910
Seven Longman's beaked whales (Indopacetus pacificus) stranded together in southern New Caledonia on 16 November 2013 (one adult male, two adult females, two subadult females, one calf, and one unknown). At this time, we have no evidence to suggest that this event was an “atypical” mass stranding associated with active naval sonar or other anthropogenic activities. The adult females were slightly larger (618–640 cm) than the adult male (590 cm). The length of the calf (ca. 300 cm) suggests it was less than a year old. Five of the whales were sampled for mitochondrial (mt) DNA analysis to confirm species identification. All shared the same haplotype over 680 bp of the mtDNA control region. High concentrations of Hg, Fe, Se, Zn (all in the liver), and Cd (in the kidneys) were detected. Necropsies revealed plastic debris in the stomach of two of the whales. One of these same whales had chronic gastritis while the other had acute pleurisy and also tested positive for morbillivirus. This infection may have been a major factor behind this mass stranding event. 相似文献
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954.
Andrea Barco Michael J. Raupach Silke Laakmann Hermann Neumann Thomas Knebelsberger 《Molecular ecology resources》2016,16(1):288-297
Sequence‐based specimen identification, known as DNA barcoding, is a common method complementing traditional morphology‐based taxonomic assignments. The fundamental resource in DNA barcoding is the availability of a taxonomically reliable sequence database to use as a reference for sequence comparisons. Here, we provide a reference library including 579 sequences of the mitochondrial cytochrome c oxidase subunit I for 113 North Sea mollusc species. We tested the efficacy of this library by simulating a sequence‐based specimen identification scenario using Best Match, Best Close Match (BCM) and All Species Barcode (ASB) criteria with three different threshold values. Each identification result was compared with our prior morphology‐based taxonomic assignments. Our simulation resulted in 87.7% congruent identifications (93.8% when excluding singletons). The highest number of congruent identifications was obtained with BCM and ASB and a 0.05 threshold. We also compared identifications with genetic clustering (Barcode Index Numbers, BINs) computed by the Barcode of Life Datasystem (BOLD). About 68% of our morphological identifications were congruent with BINs created by BOLD. Forty‐nine sequences were clustered in 16 discordant BINs, and these were divided in two classes: sequences from different species clustered in a single BIN and conspecific sequences divided in more BINs. Whereas former incongruences were probably caused by BOLD entries in need of a taxonomic update, the latter incongruences regarded taxa requiring further investigations. These include species with amphi‐Atlantic distribution, whose genetic structure should be evaluated over their entire range to produce a reliable sequence‐based identification system. 相似文献
955.
Akifumi S. Tanabe Satoshi Nagai Kohsuke Hida Motoshige Yasuike Atushi Fujiwara Yoji Nakamura Yoshihito Takano Seiji Katakura 《Molecular ecology resources》2016,16(2):402-414
The nuclear 18S‐rRNA gene has been used as a metabarcoding marker in massively parallel sequencing (MPS)‐based environmental surveys for plankton biodiversity research. However, different hypervariable regions have been used in different studies, and their utility has been debated among researchers. In this study, detailed investigations into 18S‐rRNA were carried out; we investigated the effective number of sequences deposited in international nucleotide sequence databases (INSDs), the amplification bias, and the amplicon sequence variability among the three variable regions, V1–3, V4–5 and V7–9, using in silico polymerase chain reaction (PCR) amplification based on INSDs. We also examined the primer universality and the taxonomic identification power, using MPS‐based environmental surveys in the Sea of Okhotsk, to determine which region is more useful for MPS‐based monitoring. The primer universality was not significantly different among the three regions, but the number of sequences deposited in INSDs was markedly larger for the V4–5 region than for the other two regions. The sequence variability was significantly different, with the highest variability in the V1–3 region, followed by the V7–9 region, and the lowest variability in the V4–5 region. The results of the MPS‐based environmental surveys showed significantly higher identification power in the V1–3 and V7–9 regions than in the V4–5 region, but no significant difference was detected between the V1–3 and V7–9 regions. We therefore conclude that the V1–3 region will be the most suitable for future MPS‐based monitoring of natural eukaryote communities, as the number of sequences deposited in INSDs increases. 相似文献
956.
William G. Pitt Mahsa Alizadeh Ghaleb A. Husseini Daniel S. McClellan Clara M. Buchanan Colin G. Bledsoe Richard A. Robison Rae Blanco Beverly L. Roeder Madison Melville Alex K. Hunter 《Biotechnology progress》2016,32(4):823-839
The high morbidity and mortality rate of bloodstream infections involving antibiotic‐resistant bacteria necessitate a rapid identification of the infectious organism and its resistance profile. Traditional methods based on culturing the blood typically require at least 24 h, and genetic amplification by PCR in the presence of blood components has been problematic. The rapid separation of bacteria from blood would facilitate their genetic identification by PCR or other methods so that the proper antibiotic regimen can quickly be selected for the septic patient. Microfluidic systems that separate bacteria from whole blood have been developed, but these are designed to process only microliter quantities of whole blood or only highly diluted blood. However, symptoms of clinical blood infections can be manifest with bacterial burdens perhaps as low as 10 CFU/mL, and thus milliliter quantities of blood must be processed to collect enough bacteria for reliable genetic analysis. This review considers the advantages and shortcomings of various methods to separate bacteria from blood, with emphasis on techniques that can be done in less than 10 min on milliliter‐quantities of whole blood. These techniques include filtration, screening, centrifugation, sedimentation, hydrodynamic focusing, chemical capture on surfaces or beads, field‐flow fractionation, and dielectrophoresis. Techniques with the most promise include screening, sedimentation, and magnetic bead capture, as they allow large quantities of blood to be processed quickly. Some microfluidic techniques can be scaled up. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:823–839, 2016 相似文献
957.
The spin trap 5,5-dimethyl-l-pyrroline-l-oxide (DMPO) has been applied to monitor the generation of free oxy-radicals in samples derived from isolated hearts and heart cells. · OH was trapped in the effluent of isolated hearts in the early phase of reperfusion following an ischemia time of only 10min. Radical detection was possible even when the cardioactive DMPO was added to the effluent after draining off the heart, demonstrating that the short-lived · OH was generated by components released from the affected heart. These results support the hypothesis that radicals are of relevance for reperfusion injury.
By omitting antioxidants commonly used for incubation media of cultured cells, it was possible for the first time to demonstrate the formation of · OH in the incubation solution of cardiac cells. 相似文献
By omitting antioxidants commonly used for incubation media of cultured cells, it was possible for the first time to demonstrate the formation of · OH in the incubation solution of cardiac cells. 相似文献
958.
959.
C. Gebhardt C. Blomendahl U. Schachtschabel T. Debener F. Salamini E. Ritter 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,78(1):16-22
Summary The possibility of genotype identification with RFLP fingerprints was examined with 20 tetraploid potato varieties and 38 diploid potato lines. By using a sensitive detection system for small restriction fragment length differences and highly variable potato sequences as probes, all genotypes (diploids and tetraploids) were distinguished by a minimum of two probe/enzyme combinations. The best single probe/enzyme combination distinguished 19 out of 20 4n varieties and 33 out of 38 2n lines. Intravarietal variability was very small compared to the intervarietal variability, and patterns obtained with different DNA sources of the same genotype were identical. 相似文献
960.
In 3- and 14-day-old seedlings and in the leaves of Calendula officinalis the following sterols were identified: cholestanol, campestanol, stigmastanol, cholest-7-en-3-β-ol, 24-methylcholest-7-en-3β-ol, stigmast-7-en-3β-ol, cholesterol, campesterol, sitosterol, 24-methylcholesta-5,22-dien-3β-ol, 24-methylenecholesterol, stigmasterol and clerosterol. Sitosterol was predominant in young and stigmasterol in old tissues. Young tissues contained relatively more campesterol but in old tissues a C28Δ5,22 diene was present suggesting transformation of campesterol to its Δ5,22 analog, similar to that of sitosterol to stigmasterol. All the identified sterols were present as free compounds and also in the steryl esters, glucosides, acylated glucosides and water-soluble complexes. The variations in the amounts of these fractions in the embryo axes and cotyledons of 3- and 14-day-old seedlings and the distribution of individual sterols among the fractions are discussed. 相似文献