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991.
Tracy Van Holt Wendy R. Townsend Peter Cronkleton 《Human ecology: an interdisciplinary journal》2010,38(6):791-801
We used cultural consensus models to test whether hunters shared perceptions of wildlife abundance and the relative importance
of hunting and fishing in a Guarayo indigenous community in the Bolivian Amazon. Results show that highly prized animals that
were considered rare are either those with lower reproductive rates and more sensitivity to land use changes and harvest (white-lipped
peccary and spider monkey) or those with marked seasonal distribution patterns (barred sorubim and tiger-fish). Rapidly reproducing
and resilient species (agouti and armored catfish) were perceived as abundant. More tapirs and red brocket deer were present
than predicted by scientific models possibly because hunters were harvesting these species in new forest management areas.
Residents identified hunting and fishing among their most important livelihood activities, recognized bush meat and fish as
basic food resources, and expected wildlife harvests to be part of their future livelihoods, although market-based livelihoods
and domestic replacements for bush meat were reported. 相似文献
992.
993.
Benjamin J. Thompson David A. Widdick Matthew G. Hicks Govind Chandra Iain C. Sutcliffe Tracy Palmer Matthew I. Hutchings 《Molecular microbiology》2010,77(4):943-957
Lipoproteins are a distinct class of bacterial membrane proteins that are translocated across the cytoplasmic membrane primarily by the Sec general secretory pathway and then lipidated on a conserved cysteine by the enzyme lipoprotein diacylglycerol transferase (Lgt). The signal peptide is cleaved by lipoprotein signal peptidase (Lsp) to leave the lipid‐modified cysteine at the N‐terminus of the mature lipoprotein. In all Gram‐positive bacteria tested to date this pathway is non‐essential and the lipid attaches the protein to the outer leaflet of the cytoplasmic membrane. Here we identify lipoproteins in the model Gram‐positive bacterium Streptomyces coelicolor using bioinformatics coupled with proteomic and downstream analysis. We report that Streptomyces species translocate large numbers of lipoproteins out via the Tat (twin arginine translocase) pathway and we present evidence that lipoprotein biogenesis might be an essential pathway in S. coelicolor. This is the first analysis of lipoproteins and lipoprotein biogenesis in Streptomyces and provides the first evidence that lipoprotein biogenesis could be essential in a Gram‐positive bacterium. This report also provides the first experimental evidence that Tat plays a major role in the translocation of lipoproteins in a specific bacterium. 相似文献
994.
995.
Sriram Tyagarajan Prasun K. Chakravarty Bishan Zhou Michael H. Fisher Mathew J. Wyvratt Kathy Lyons Tracy Klatt Xiaohua Li Sanjeev Kumar Brande Williams John Felix Birgit T. Priest Richard M. Brochu Vivien Warren McHardy Smith Maria Garcia Gregory J. Kaczorowski William J. Martin Catherine Abbadie Erin McGowan William H. Parsons 《Bioorganic & medicinal chemistry letters》2010,20(18):5536-5540
Voltage-gated sodium channels have been shown to play a critical role in neuropathic pain. With a goal to develop potent peripherally active sodium channel blockers, a series of low molecular weight biaryl substituted imidazoles, oxazoles, and thiazole carboxamides were identified with good in vitro and in vivo potency. 相似文献
996.
Kumar GD Chavarria GE Charlton-Sevcik AK Yoo GK Song J Strecker TE Siim BG Chaplin DJ Trawick ML Pinney KG 《Bioorganic & medicinal chemistry letters》2010,20(22):6610-6615
A series of thiosemicarbazone analogs based on the benzophenone, thiophene, pyridine, and fluorene molecular frameworks has been prepared by chemical synthesis and evaluated as small-molecule inhibitors of the cysteine proteases cathepsin L and cathepsin B. The two most potent inhibitors of cathepsin L in this series (IC(50)<135 nM) are brominated-benzophenone thiosemicarbazone analogs that are further functionalized with a phenolic moiety (2 and 6). In addition, a bromo-benzophenone thiosemicarbazone acetyl derivative (3) is also strongly inhibitory against cathepsin L (IC(50)=150.8 nM). Bromine substitution in the thiophene series results in compounds that demonstrate only moderate inhibition of cathepsin L. The two most active analogs in the benzophenone thiosemicarbazone series are highly selective for their inhibition of cathepsin L versus cathepsin B. 相似文献
997.
Abstract. 1. The effects of human presence on the behavioural response and productivity of a native wasp species of North America ( Polistes fuscatus ) and an invasive wasp species ( Polistes dominulus ) were examined in a field experiment. Over a 3-month period, colonies of each species were exposed to human presence at either low (biweekly) or high (daily) levels. At 2-week intervals, wasp response to human presence was recorded for all colonies via an index, ranging from no response (0) to an attack (4).
2. The levels of human presence had no effect on wasp response or colony productivity but foundresses of both species increased their response level the closer a human was to the nest. In addition, foundresses of P. fuscatus became more aggressive over time, corresponding to after adult offspring emerged, whereas foundresses of P. dominulus did not change their response level after the emergence of offspring.
3. The adult offspring of P. dominulus responded to human presence at a level similar to that of the foundress, whereas adult offspring of P. fuscatus exhibited a lower response to human presence than that of the foundress. The more distinctive aposematic coloration of P. dominulus may play a role in the behavioural differences between species; it may be more effective in deterring predators, and with the result that leaving the nest to defend it is less often necessary. Accordingly, the less aggressive response to human presence by P. dominulus may contribute to its success as an introduced species in North America. 相似文献
2. The levels of human presence had no effect on wasp response or colony productivity but foundresses of both species increased their response level the closer a human was to the nest. In addition, foundresses of P. fuscatus became more aggressive over time, corresponding to after adult offspring emerged, whereas foundresses of P. dominulus did not change their response level after the emergence of offspring.
3. The adult offspring of P. dominulus responded to human presence at a level similar to that of the foundress, whereas adult offspring of P. fuscatus exhibited a lower response to human presence than that of the foundress. The more distinctive aposematic coloration of P. dominulus may play a role in the behavioural differences between species; it may be more effective in deterring predators, and with the result that leaving the nest to defend it is less often necessary. Accordingly, the less aggressive response to human presence by P. dominulus may contribute to its success as an introduced species in North America. 相似文献
998.
David G. Jenkins† Camille R. Brescacin Craig V. Duxbury Jennifer A. Elliott Jennafer A. Evans Katherine R. Grablow Melissa Hillegass Boyd N. Lyon‡ Genevieve A. Metzger Michelle L. Olandese Diana Pepe Greg A. Silvers Hiliary N. Suresch Tracy N. Thompson Christina M. Trexler Graham E. Williams Natalie C. Williams Sara E. Williams 《Global Ecology and Biogeography》2007,16(4):415-425
Aim The aim of this study is to answer the questions: (1) do small organisms disperse farther than large, or vice versa; and (2) does the observed pattern differ for passive and active dispersers? These questions are central to several themes in biogeography (including microbial biogeography), macroecology, metacommunity ecology and conservation biology. Location The meta‐analysis was conducted using published data collected worldwide. Methods We collected and analysed 795 data values in the peer‐reviewed literature for direct observations of both maximal dispersal distance and mass of the dispersing organisms (e.g. seeds, not trees). Analysed taxa ranged in size from bacteria to whales. We applied macroecology analyses based on null models (using Monte Carlo randomizations) to test patterns relative to specific hypotheses. Results Collected dispersal distance and mass data spanned 9 and 21 orders of magnitude, respectively. Active dispersers dispersed significantly farther (P < 0.001) and were significantly greater in mass (P < 0.001) than passive dispersers. Overall, size matters: larger active dispersers attained greater maximum observed dispersal distances than smaller active dispersers. In contrast, passive‐disperser distances were random with respect to propagule mass, but not uniformly random, in part due to sparse data available for tiny propagules. Conclusions Size is important to maximal dispersal distance for active dispersers, but not for passive dispersers. Claims that microbes disperse widely cannot be tested by current data based on direct observations of dispersal: indirect approaches will need to be applied. Distance–mass relationships should contribute to a resolution of neutral and niche‐based metacommunity theories by helping scale expectations for dispersal limitation. Also, distance–mass relationships should inform analyses of latitudinal species richness and conservation biology topics such as fragmentation, umbrella species and taxonomic homogenization. 相似文献
999.
Models of macrophage subtypes require molecular characterization to reliably facilitate their differentiation. Although CD16+ (Fc-gamma III receptor) monocytes that express CD163 (a hemoglobin/haptoglobin receptor) have been implicated in a variety of disease states, the conditions necessary to establish lineages of these cell subtypes remains unknown. The current investigations utilize a cell line derived from acute myelogenous leukemia lineage, MonoMac-1, to interrogate the factors that promote the development of CD16+ macrophages that express CD163. Results implicate the glucocorticoid pathway as well as c-fms signaling based on the action of dexamethasone and macrophage colony-stimulating factor-1 in promoting CD16+ expression, in addition to phorbol myristate acetate and lipopolysaccharides treatment. The ability of glucocorticoid and c-fms receptor antagonists to inhibit CD16+ cell formation further establishes the role of these pathways in CD16 expression in this cell line. In view of the inherent difficulty in working with primary cells as well as donor variation, cell lines may be preferable to primary cells for their consistency. We envision that the process we use to induce CD16 expression in this cell type will be useful for screening and identification of drug candidates potentially useful for the treatment of diseases where the etiology involves the expansion of the CD16+ monocytes subset or the accumulation of CD163+ tissue macrophages. 相似文献
1000.
Charlon A. Ligson Tracy D. Tabalanza Ronald D. Villanueva Patrick C. Cabaitan 《Restoration Ecology》2020,28(1):244-251
Over the last 20 years, coral sexual propagation techniques for reef restoration have been steadily developed and improved. However, these techniques involve considerable time and costs to grow coral propagules. There is a need to examine the optimal size of juvenile corals for outplantation. Here, we outplanted sexually propagated small (3–5 mm diameter) and large (10–15 mm diameter) Acropora verweyi corals at 4 months after fertilization at two sites in northwestern Philippines, and compared their survival and radial growth rate after a year. A. verweyi coral juveniles (n = 240) exhibited an overall mean survival of 29.5% and growth rate of 11.12 ± 6.2 mm/year (mean ± SD). Large colonies had a significantly higher growth rate than smaller colonies. Although survivorship of large juveniles was significantly better than that of the smaller ones at one site, it did not differ significantly at the other. Each 4‐month‐old coral cost US$1.52 to produce, while the cost of each of the outplanted juveniles (n = 240) was about US$2.67, whereas the cost of each survivor about a year after outplantation was US$11.47. Results suggest that A. verweyi reared in ex situ nurseries for only 4 months can survive reasonably well when outplanted onto coral reefs. 相似文献