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121.
Emotional signals are perceived whether or not we are aware of it. The evidence so far mostly came from studies with facial expressions. Here, we investigated whether the pattern of non-conscious face expression perception is found for whole body expressions. Continuous flash suppression (CFS) was used to measure the time for neutral, fearful, and angry facial or bodily expressions to break from suppression. We observed different suppression time patterns for emotions depending on whether the stimuli were faces or bodies. The suppression time for anger was shortest for bodily expressions, but longest for the facial expressions. This pattern indicates different processing and detection mechanisms for faces and bodies outside awareness, and suggests that awareness mechanisms associated with dorsal structures might play a role in becoming conscious of angry bodily expressions. 相似文献
122.
Simon M. Langer Kristina Hopfensperger Shilpa S. Iyer Edward F. Kreider Gerald H. Learn Lan-Hui Lee Beatrice H. Hahn Daniel Sauter 《PloS one》2015,10(11)
Background
Pandemic strains of HIV-1 (group M) encode a total of nine structural (gag, pol, env), regulatory (rev, tat) and accessory (vif, vpr, vpu, nef) genes. However, some subtype A and C viruses exhibit an unusual gene arrangement in which the first exon of rev (rev1) and the vpu gene are placed in the same open reading frame. Although this rev1-vpu gene fusion is present in a considerable fraction of HIV-1 strains, its functional significance is unknown.Results
Examining infectious molecular clones (IMCs) of HIV-1 that encode the rev1-vpu polymorphism, we show that a fusion protein is expressed in infected cells. Due to the splicing pattern of viral mRNA, however, these same IMCs also express a regular Vpu protein, which is produced at much higher levels. To investigate the function of the fusion gene, we characterized isogenic IMC pairs differing only in their ability to express a Rev1-Vpu protein. Analysis in transfected HEK293T and infected CD4+ T cells showed that all of these viruses were equally active in known Vpu functions, such as down-modulation of CD4 or counteraction of tetherin. Furthermore, the polymorphism did not affect Vpu-mediated inhibition of NF-кB activation or Rev-dependent nuclear export of incompletely spliced viral mRNAs. There was also no evidence for enhanced replication of Rev1-Vpu expressing viruses in primary PBMCs or ex vivo infected human lymphoid tissues. Finally, the frequency of HIV-1 quasispecies members that encoded a rev1-vpu fusion gene did not change in HIV-1 infected individuals over time.Conclusions
Expression of a rev1-vpu fusion gene does not affect regular Rev and Vpu functions or alter HIV-1 replication in primary target cells. Since there is no evidence for increased replication fitness of rev1-vpu encoding viruses, this polymorphism likely emerged in the context of other mutations within and/or outside the rev1-vpu intergenic region, and may have a neutral phenotype. 相似文献123.
Vincent Kayina Samuel Kyobe Fred A. Katabazi Edgar Kigozi Moses Okee Beatrice Odongkara Harriet M. Babikako Christopher C. Whalen Moses L. Joloba Philippa M. Musoke Ezekiel Mupere 《PloS one》2015,10(4)
Background
We determined prevalence of pertussis infection and its associated host and environmental factors to generate information that would guide strategies for disease control.Methods
In a cross-sectional study, 449 children aged 3 months to 12 years with persistent cough lasting ≥14 days were enrolled and evaluated for pertussis using DNA polymerase chain reaction (PCR) and ELISA serology tests.Results
Pertussis prevalence was 67 (15% (95% Confidence Interval (CI): 12–18)) and 81 (20% (95% CI: 16–24)) by PCR and ELISA, respectively among 449 participating children. The prevalence was highest in children with >59 months of age despite high vaccination coverage of 94% in this age group. Study demographic and clinical characteristics were similar between pertussis and non-pertussis cases. Of the 449 children, 133 (30%) had a coughing household member and 316 (70%) did not. Among 133 children that had a coughing household member, sex of child, sharing bed with a coughing household member and having a coughing individual in the neighborhood were factors associated with pertussis. Children that had shared a bed with a coughing household individual had seven-fold likelihood of having pertussis compared to children that did not (odds ratio (OR) 7.16 (95% CI: 1.24–41.44)). Among the 316 children that did not have a coughing household member, age <23 months, having or contact with a coughing individual in neighborhood, a residence with one room, and having a caretaker with >40 years of age were the factors associated with pertussis. Age <23months was three times more likely to be associated with pertussis compared to age 24–59 months (OR 2.97 (95% CI: 1.07–8.28)).Conclusion
Findings suggest high prevalence of pertussis among children with persistent cough at a health facility and it was marked in children >59 months of age, suggesting the possibility of waning immunity. The factors associated with pertussis varied by presence or absence of a coughing household member. 相似文献124.
Melanie Brügger Thomas Dmoulins G. Tuba Barut Beatrice Zumkehr Blandina I. Oliveira Esteves Kemal Mehinagic Quentin Haas Aline Schgler Marie-Anne Rameix-Welti Jean-Franois Elouët Ueli Moehrlen Thomas M. Marti Ralph A. Schmid Artur Summerfield Horst Posthaus Nicolas Ruggli Sean R. R. Hall Marco P. Alves 《PLoS pathogens》2021,17(7)
125.
Species with a wide distribution over latitudinal gradients often exhibit increasing growth and development rates towards
higher latitudes. Ecological theory predicts that these fast-growing genotypes are, in the absence of trade-offs with fast
growth, better competitors than low-latitude conspecifics. While knowledge on key ecological traits along latitudinal clines
is important for understanding how these clines are maintained, the relative competitive ability of high latitude individuals
against low latitude conspecifics has not been tested. Growth and development rates of the common frog Rana temporaria increase along the latitudinal gradient across Scandinavia. Here we investigated larval competition over food resources within
and between two R. temporaria populations originating from southern and northern Sweden in an outdoor common garden experiment. We used a factorial design,
where southern and northern tadpoles were reared either as single populations or as mixes of the two populations at two densities
and predator treatments (absence and non-lethal presence of Aeshna dragonfly larvae). Tadpoles from the high latitude population grew and developed faster and in the beginning of the experiment
they hid less and were more active than tadpoles from the low latitude population. When raised together with high latitude
tadpoles the southern tadpoles had a longer larval period, however, the response of high latitude tadpoles to the competition
by low latitude tadpoles did not differ from their response to intra-population competition. This result was not significantly
affected by density or predator treatments. Our results support the hypothesis that high latitude populations are better competitors
than their low latitude conspecifics, and suggest that in R. temporaria fast growth and development trade off with other fitness components along the latitudinal gradient across Scandinavia. 相似文献
126.
Sven Heiling Meredith C. Schuman Matthias Schoettner Purba Mukerjee Beatrice Berger Bernd Schneider Amir R. Jassbi Ian T. Baldwin 《The Plant cell》2010,22(1):273-292
We identified 11 17-hydroxygeranyllinalool diterpene glycosides (HGL-DTGs) that occur in concentrations equivalent to starch (mg/g fresh mass) in aboveground tissues of coyote tobacco (Nicotiana attenuata) and differ in their sugar moieties and malonyl sugar esters (0-2). Concentrations of HGL-DTGs, particularly malonylated compounds, are highest in young and reproductive tissues. Within a tissue, herbivore elicitation changes concentrations and biosynthetic kinetics of individual compounds. Using stably transformed N. attenuata plants silenced in jasmonate production and perception, or production of N. attenuata Hyp-rich glycopeptide systemin precursor by RNA interference, we identified malonylation as the key biosynthetic step regulated by herbivory and jasmonate signaling. We stably silenced N. attenuata geranylgeranyl diphosphate synthase (ggpps) to reduce precursors for the HGL-DTG skeleton, resulting in reduced total HGL-DTGs and greater vulnerability to native herbivores in the field. Larvae of the specialist tobacco hornworm (Manduca sexta) grew up to 10 times as large on ggpps silenced plants, and silenced plants suffered significantly more damage from herbivores in N. attenuata''s native habitat than did wild-type plants. We propose that high concentrations of HGL-DTGs effectively defend valuable tissues against herbivores and that malonylation may play an important role in regulating the distribution and storage of HGL-DTGs in plants. 相似文献
127.
Feliciana Real-Fernández Francesca Nuti M. Angeles Bonache Marco Boccalini Stefano Chimichi Mario Chelli Anna Maria Papini 《Amino acids》2010,39(2):599-604
The synthesis of N-protected glycosyl amino acids from amines has been investigated and it was found that, under microwave conditions, glycosylamines
could be hydrolyzed leading to new products containing a glycosyl ester linkage. The efficiency of the microwave-induced glycosylation
of aspartic acid was studied comparing the microwave activity between amide and ester bond formation. Different sugar moieties
have been employed to demonstrate the simple and reproducible coupling methodology. New glycosyl ester compounds were further
characterized by NMR spectroscopy. 相似文献
128.
Thewlis KM Aldegheri L Harries MH Mookherjee C Oliosi B Ward SE 《Bioorganic & medicinal chemistry letters》2010,20(23):7116-7119
A series of novel AMPA receptor positive modulators displaying CNS penetration have been discovered with sub-micromolar activity and good selectivity over the cardiac channel receptor, hERG. We describe here the synthesis of these compounds which are biaryl pyrrolidine and tetrahydrofuran sulfonamides and disclose their activities against the human GluA2 flip isoform homotetrameric receptor. 相似文献
129.
Bruey JM Bruey-Sedano N Luciano F Zhai D Balpai R Xu C Kress CL Bailly-Maitre B Li X Osterman A Matsuzawa S Terskikh AV Faustin B Reed JC 《Cell》2007,129(1):45-56
Caspases are intracellular proteases that cleave substrates involved in apoptosis or inflammation. In C. elegans, a paradigm for caspase regulation exists in which caspase CED-3 is activated by nucleotide-binding protein CED-4, which is suppressed by Bcl-2-family protein CED-9. We have identified a mammalian analog of this caspase-regulatory system in the NLR-family protein NALP1, a nucleotide-dependent activator of cytokine-processing protease caspase-1, which responds to bacterial ligand muramyl-dipeptide (MDP). Antiapoptotic proteins Bcl-2 and Bcl-X(L) bind and suppress NALP1, reducing caspase-1 activation and interleukin-1beta (IL-1beta) production. When exposed to MDP, Bcl-2-deficient macrophages exhibit more caspase-1 processing and IL-1beta production, whereas Bcl-2-overexpressing macrophages demonstrate less caspase-1 processing and IL-1beta production. The findings reveal an interaction of host defense and apoptosis machinery. 相似文献
130.
Gle Corine; Del Amo Yolanda; Bec Beatrice; Sautour Benoit; Froidefond Jean-Marie; Gohin Francis; Maurer Daniele; Plus Martin; Laborde Pierre; Chardy Pierre 《Journal of plankton research》2007,29(11):999-1014
Phytoplankton dynamics were assessed in the macrotidal ecosystemof Arcachon Bay through high-frequency surveys over a 5-yearperiod in order to characterize typology of environmental conditionsat the onset of the productive period. Temporal variations ofhydrological and biological parameters were examined in externaland internal waters of the lagoon, during the winter–springperiods from 1999 to 2003. An additional survey was performedduring winter–spring 2005 in order to study the verticalstructure of the water column. The occurrence of winter phytoplanktonblooms between January and March emerged as a recurrent event.The early onset of the productive period is influenced by thebiological functioning of adjacent Bay of Biscay oceanic waters.It is hypothesized that under a propitious hydrodynamic regime,phytoplankton inocula from the Bay of Biscay enter in the ArcachonBay where cells presumably find favourable conditions for theirfast development. The timing of the onset of those winter bloomsin Arcachon Bay seems to be mainly influenced by the presenceof anticyclonic weather conditions (associated with an increasein incident irradiance) during late winter (i.e. by February),while the water column does not show any particular stabilizationnor stratification liable to facilitate the onset of these blooms.Moreover, these winter blooms dominated by diatoms led to anearly nutrient depletion which could have inevitable consequenceson the structuration of the food web during spring and summer. 相似文献