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131.
Brian A Stacy Mario Santoro Juan Alberto Morales Louis M Huzella Victor F Kalasinsky Allen Foley Nancy Mettee Elliott R Jacobson 《Diseases of aquatic organisms》2008,80(1):45-49
Eighteen green turtles Chelonia mydas recovered from the Atlantic and Gulf coasts of Florida and Tortuguero National Park, Costa Rica, were diagnosed with renal oxalosis by histopathological examination. Affected sea turtles included 14 adults and 4 immature animals, which comprised 26% (18/69) of green turtle necropsy cases available for review. Calcium oxalate deposition ranged from small to moderate amounts and was associated with granuloma formation and destruction of renal tubules. All affected turtles died from traumatic events or health problems unrelated to renal oxalosis; however, 1 immature turtle had notable associated renal injury. Crystal composition was confirmed by infrared and scanning electron microscopy and energy dispersive X-ray analysis. The source of calcium oxalate is unknown and is presumed to be of dietary origin. 相似文献
132.
Beaster-Jones L Kaltenbach SL Koop D Yuan S Chastain R Holland LZ 《Development genes and evolution》2008,218(11-12):599-611
In the basal chordate amphioxus (Branchiostoma), somites extend the full length of the body. The anteriormost somites segment during the gastrula and neurula stages from dorsolateral grooves of the archenteron. The remaining ones pinch off, one at a time, from the tail bud. These posterior somites appear to be homologous to those of vertebrates, even though the latter pinch off from the anterior end of bands of presomitic mesoderm rather than directly from the tail bud. To gain insights into the evolution of mesodermal segmentation in chordates, we determined the expression of ten genes in nascent amphioxus somites. Five (Uncx4.1, NeuroD/atonal-related, IrxA, Pcdhdelta2-17/18, and Hey1) are expressed in stripes in the dorsolateral mesoderm at the gastrula stage and in the tail bud while three (Paraxis, Lcx, and Axin) are expressed in the posterior mesendoderm at the gastrula and neurula stages and in the tail bud at later stages. Expression of two genes (Pbx and OligA) suggests roles in the anterior somites that may be unrelated to initial segmentation. Together with previous data, our results indicate that, with the exception that Engrailed is only segmentally expressed in the anterior somites, the genetic mechanisms controlling formation of both the anterior and posterior somites are probably largely identical. Thus, the fundamental pathways for mesodermal segmentation involving Notch-Delta, Wnt/beta-catenin, and Fgf signaling were already in place in the common ancestor of amphioxus and vertebrates although budding of somites from bands of presomitic mesoderm exhibiting waves of expression of Notch, Wnt, and Fgf target genes was likely a vertebrate novelty. Given the conservation of segmentation gene expression between amphioxus and vertebrate somites, we propose that the clock mechanism may have been established in the basal chordate, while the wavefront evolved later in the vertebrate lineage. 相似文献
133.
Thermodynamic parameters are reported for duplex formation of 40 self-complementary RNA duplexes containing wobble terminal base pairs with all possible 3′ single and double-nucleotide overhangs, mimicking the structures of short interfering RNAs (siRNA) and microRNAs (miRNA). Based on nearest neighbor analysis, the addition of a single 3′ dangling nucleotide increases the stability of duplex formation up to 1 kcal/mol in a sequence-dependent manner. The addition of a second dangling nucleotide increases the stability of duplexes closed with wobble base pairs in an idiosyncratic manner. The results allow for the development of a nearest neighbor model, which improves the predication of free energy and melting temperature for duplexes closed by wobble base pairs with 3′ single or double-nucleotide overhangs. Phylogenetic analysis of naturally occurring miRNAs was performed. Selection of the effector miR strand of the mature miRNA duplex appears to be dependent on the orientation of the GU closing base pair rather than the identity of the 3′ double-nucleotide overhang. Thermodynamic parameters for the 5′ single terminal overhangs adjacent to wobble closing base pairs are also presented. 相似文献
134.
Biodiversity conservation,yield, and alternative products in coffee agroecosystems in Sumatra,Indonesia 总被引:1,自引:0,他引:1
Stacy?M.?PhilpottEmail author Peter?Bichier Robert?A.?Rice Russell?Greenberg 《Biodiversity and Conservation》2008,17(8):1805-1820
Agroecology and conservation must overlap to protect biodiversity and farmer livelihoods. Coffee agroecosystems with complex
shade canopies protect biodiversity. Yet, few have examined biodiversity in coffee agroecosystems in Asia relative to the
Americas and many question whether coffee agroecosystems can play a similar role for conservation. We examined vegetation,
ant and bird diversity, coffee yields and revenues, and harvest of alternative products in coffee farms and forests in SW
Sumatra, Indonesia near Bukit Barisan Selatan National Park (BBS). BBS is among the last habitats for large mammals in Sumatra
and >15,000 families illegally cultivate coffee inside of BBS. As a basis for informing management recommendations, we compared
the conservation potential and economic outputs from farms inside and outside of BBS. Forests had higher canopy cover, canopy
depth, tree height, epiphyte loads, and more emergent trees than coffee farms. Coffee farms inside BBS had more epiphytes
and trees and fewer coffee plants than farms outside BBS. Tree, ant, and bird richness was significantly greater in forests
than in coffee farms, and richness did not differ in coffee farms inside and outside of BBS. Species similarity of forest
and coffee trees, ants, and birds was generally low (<50%). Surprisingly, farms inside the park were significantly older,
but farm size, coffee yields, and revenues from coffee did not depend on farm location. Farmers outside BBS received higher
prices for their coffee and also more often produced other crops in their coffee fields such that incentives could be created
to draw illegal farmers out of the park. We also discuss these results with reference to similar work in Chiapas, Mexico to
compare the relative contribution of coffee fields to conservation in the two continents, and discuss implications for working
with farmers in Sumatra towards conservation plans incorporating sustainable coffee production. 相似文献
135.
Development and Optimization of a Novel Immunomagnetic Separation- Bacteriophage Assay for Detection of Salmonella enterica Serovar Enteritidis in Broth 总被引:1,自引:0,他引:1 下载免费PDF全文
Salmonella is the second-leading cause of food-borne illness in most developed countries, causing diarrhea, cramps, vomiting, and often fever. Many rapid methods are available for detection of Salmonella in foods, but these methods are often insensitive or expensive or require a high degree of technical ability to perform. In this paper we describe development and characterization of a novel assay that utilizes the normal infection cycle of bacteriophage SJ2 for detection of Salmonella enterica serovar Enteritidis in broth. The assay consists of four main stages: (i) capture and concentration of target cells by using immunomagnetic separation (IMS); (ii) infection of the target bacterium with phage; (iii) amplification and recovery of progeny phage; and (iv) assay of progeny phage on the basis of their effect on a healthy population of host cells (signal-amplifying cells). The end point of the assay can be determined by using either fluorescence or optical density measurements. The detection limit of the assay in broth is less than 104 CFU/ml, and the assay can be performed in 4 to 5 h. The results of this study demonstrate that the IMS-bacteriophage assay is a rapid, simple, and sensitive technique for detection of Salmonella serovar Enteritidis in broth cultures which can be applied to preenriched food samples. 相似文献
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139.
Josh A. Honig Christine Kubik Martin Majewski Christine Poulsen Eric Weibel Keenan Amundsen Scott E. Warnke William A. Meyer Stacy A. Bonos 《Molecular breeding : new strategies in plant improvement》2014,34(1):185-203
Creeping bentgrass (Agrostis stolonifera L.) is the most widely utilized cool-season turf species for intensively managed sports playing surfaces, including bowling greens and golf course putting greens, tees, and fairways. One of the biggest disease problems affecting creeping bentgrass is dollar spot disease caused by Sclerotinia homoeocarpa F.T. Bennett. Relative to traditional food crops, little attention has been paid to applying molecular technology to traditional creeping bentgrass breeding programs. The objective of this study was to develop a PCR-based linkage map of creeping bentgrass and identify quantitative trait loci (QTLs) associated with dollar spot resistance. Mapping populations segregating for dollar spot resistance were created, phenotyped for disease resistance, and genotyped for simple sequence repeat, conserved intron scanning primer, intron length polymorphism, and amplified fragment length polymorphism markers. As expected, 14 linkage groups (LGs) were detected for each parental map, covering a total of 1,424 and 1,374 cM for the 7418-3 and the L93-10 parental maps, respectively. A total of eight QTL regions (23 markers) for dollar spot resistance were observed for three isolates (Crenshaw, PRG, and UMass1) in our creeping bentgrass mapping populations. LGs 1, 4, and 5 contained at least two overlapping QTL regions to different isolates, indicating that these regions may play a significant role in dollar spot resistance. Identification of QTLs associated with disease resistance will help to facilitate marker-assisted selection in traditional creeping bentgrass breeding programs. 相似文献
140.
Establishing different types of conservation zones is becoming commonplace. However, spatial prioritization methods that can accommodate multiple zones are poorly understood in theory and application. It is typically assumed that management regulations across zones have differential levels of effectiveness (“zone effectiveness”) for biodiversity protection, but the influence of zone effectiveness on achieving conservation targets has not yet been explored. Here, we consider the zone effectiveness of three zones: permanent closure, partial protection, and open, for planning for the protection of five different marine habitats in the Vatu-i-Ra Seascape, Fiji. We explore the impact of differential zone effectiveness on the location and costs of conservation priorities. We assume that permanent closure zones are fully effective at protecting all habitats, open zones do not contribute towards the conservation targets and partial protection zones lie between these two extremes. We use four different estimates for zone effectiveness and three different estimates for zone cost of the partial protection zone. To enhance the practical utility of the approach, we also explore how much of each traditional fishing ground can remain open for fishing while still achieving conservation targets. Our results show that all of the high priority areas for permanent closure zones would not be a high priority when the zone effectiveness of the partial protection zone is equal to that of permanent closure zones. When differential zone effectiveness and costs are considered, the resulting marine protected area network consequently increases in size, with more area allocated to permanent closure zones to meet conservation targets. By distributing the loss of fishing opportunity equitably among local communities, we find that 84–88% of each traditional fishing ground can be left open while still meeting conservation targets. Finally, we summarize the steps for developing marine zoning that accounts for zone effectiveness. 相似文献