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排序方式: 共有453条查询结果,搜索用时 392 毫秒
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Danny V. Colombara Bernardo Hernández Alexandra Schaefer Nicholas Zyznieuski Miranda F. Bryant Sima S. Desai Marielle C. Gagnier Casey K. Johanns Claire R. McNellan Erin B. Palmisano Diego Ríos-Zertuche Paola Zú?iga-Brenes Emma Iriarte Ali H. Mokdad 《PloS one》2016,11(4)
Indigenous women in Mesoamerica experience disproportionately high maternal mortality rates and are less likely to have institutional deliveries. Identifying correlates of institutional delivery, and satisfaction with institutional deliveries, may help improve facility utilization and health outcomes in this population. We used baseline surveys from the Salud Mesoamérica Initiative to analyze data from 10,895 indigenous and non-indigenous women in Guatemala and Mexico (Chiapas State) and indigenous women in Panama. We created multivariable Poisson regression models for indigenous (Guatemala, Mexico, Panama) and non-indigenous (Guatemala, Mexico) women to identify correlates of institutional delivery and satisfaction. Compared to their non-indigenous peers, indigenous women were substantially less likely to have an institutional delivery (15.2% vs. 41.5% in Guatemala (P<0.001), 29.1% vs. 73.9% in Mexico (P<0.001), and 70.3% among indigenous Panamanian women). Indigenous women who had at least one antenatal care visit were more than 90% more likely to have an institutional delivery (adjusted risk ratio (aRR) = 1.94, 95% confidence interval (CI): 1.44–2.61), compared to those who had no visits. Indigenous women who were advised to give birth in a health facility (aRR = 1.46, 95% CI: 1.18–1.81), primiparous (aRR = 1.44, 95% CI: 1.24–1.68), informed that she should have a Caesarean section (aRR = 1.41, 95% CI: 1.21–1.63), and had a secondary or higher level of education (aRR = 1.36, 95% CI: 1.04–1.79) also had substantially higher likelihoods of institutional delivery. Satisfaction among indigenous women was associated with being able to be accompanied by a community health worker (aRR = 1.15, 95% CI: 1.05–1.26) and facility staff speaking an indigenous language (aRR = 1.10, 95% CI: 1.02–1.19). Additional effort should be exerted to increase utilization of birthing facilities by indigenous and poor women in the region. Improving access to antenatal care and opportunities for higher-level education may increase institutional delivery rates, and providing culturally adapted services may improve satisfaction. 相似文献
95.
N López-Moratalla A J Iriarte M J López-Zabalza E Santiago 《Biochemical and biophysical research communications》1978,85(4):1610-1613
The hydrolytic activity of rat liver F1-ATPase was stimulated up to 60% by FAD concentrations as low as 10-10 M. Stimulations as high as 100% were obtained with similar concentrations of CoQ. 相似文献
96.
Santos-Jiménez José Leonardo de Barros Montebianco Caroline Vidal Andreza Henrique G. Ribeiro Simone Barreto-Bergter Eliana Vaslin Maite Freitas Silva 《BioControl》2022,67(1):75-87
BioControl - Passion fruit woodiness disease is responsible for severe losses in passion fruit production around the world. The disease is caused by Cowpea aphid-borne mosaic virus (CABMV), an... 相似文献
97.
Latasa C García B Echeverz M Toledo-Arana A Valle J Campoy S García-del Portillo F Solano C Lasa I 《Journal of bacteriology》2012,194(14):3708-3722
The Rcs phosphorelay pathway is a complex signaling pathway involved in the regulation of many cell surface structures in enteric bacteria. In response to environmental stimuli, the sensor histidine kinase (RcsC) autophosphorylates and then transfers the phosphate through intermediary steps to the response regulator (RcsB), which, once phosphorylated, regulates gene expression. Here, we show that Salmonella biofilm development depends on the phosphorylation status of RcsB. Thus, unphosphorylated RcsB, hitherto assumed to be inactive, is essential to activate the expression of the biofilm matrix compounds. The prevention of RcsB phosphorylation either by the disruption of the phosphorelay at the RcsC or RcsD level or by the production of a nonphosphorylatable RcsB allele induces biofilm development. On the contrary, the phosphorylation of RcsB by the constitutive activation of the Rcs pathway inhibits biofilm development, an effect that can be counteracted by the introduction of a nonphosphorylatable RcsB allele. The inhibition of biofilm development by phosphorylated RcsB is due to the repression of CsgD expression, through a mechanism dependent on the accumulation of the small noncoding RNA RprA. Our results indicate that unphosphorylated RcsB plays an active role for integrating environmental signals and, more broadly, that RcsB phosphorylation acts as a key switch between planktonic and sessile life-styles in Salmonella enterica serovar Typhimurium. 相似文献
98.
Carreras-Aubets M Montero FE Kostadinova A Gibson DI Carrassón M 《Systematic parasitology》2012,82(3):185-199
Two frequently reported but poorly known hemiurid digeneans, Lecithochirium musculus (Looss, 1907) (Lecithochiriinae), from the stomach of Trachinus draco and Citharus linguatula, and Ectenurus lepidus Looss, 1907 (Dinurinae), from the stomach of Spicara maena, are redescribed based on material from off the Barcelona coast of the western Mediterranean. The two species are commented upon, and Lecithochirium israelense Fischthal, 1980 is considered a synonym of L. musculus. Records of the two species in the Mediterranean Basin and North East Atlantic region are summarised. 相似文献
99.
Elías Barquero-Calvo Raquel Conde-Alvarez Carlos Chacón-Díaz Lucía Quesada-Lobo Anna Martirosyan Caterina Guzmán-Verri Maite Iriarte Mateja Mancek-Keber Roman Jerala Jean Pierre Gorvel Ignacio Moriyón Edgardo Moreno Esteban Chaves-Olarte 《PloS one》2009,4(6)
Background
During evolution, innate immunity has been tuned to recognize pathogen-associated molecular patterns. However, some α-Proteobacteria are stealthy intracellular pathogens not readily detected by this system. Brucella members follow this strategy and are highly virulent, but other Brucellaceae like Ochrobactrum are rhizosphere inhabitants and only opportunistic pathogens. To gain insight into the emergence of the stealthy strategy, we compared these two phylogenetically close but biologically divergent bacteria.Methodology/Principal Findings
In contrast to Brucella abortus, Ochrobactrum anthropi did not replicate within professional and non-professional phagocytes and, whereas neutrophils had a limited action on B. abortus, they were essential to control O. anthropi infections. O. anthropi triggered proinflammatory responses markedly lower than Salmonella enterica but higher than B. abortus. In macrophages and dendritic cells, the corresponding lipopolysaccharides reproduced these grades of activation, and binding of O. anthropi lipopolysaccharide to the TLR4 co-receptor MD-2 and NF-κB induction laid between those of B. abortus and enteric bacteria lipopolysaccharides. These differences correlate with reported variations in lipopolysaccharide core sugars, sensitivity to bactericidal peptides and outer membrane permeability.Conclusions/Significance
The results suggest that Brucellaceae ancestors carried molecules not readily recognized by innate immunity, so that non-drastic variations led to the emergence of stealthy intracellular parasites. They also suggest that some critical envelope properties, like selective permeability, are profoundly altered upon modification of pathogen-associated molecular patterns, and that this represents a further adaptation to the host. It is proposed that this adaptive trend is relevant in other intracellular α-Proteobacteria like Bartonella, Rickettsia, Anaplasma, Ehrlichia and Wolbachia. 相似文献100.
Alien plant species, such as Caulerpa racemosa var. cylindracea, that invade Mediterranean marine vegetated habitats can affect habitat structure. In turn, changes in habitat structure
may affect the associated invertebrate assemblages, either through changes in habitat selection or as a result of altered
predation efficiency. In order to test for effects of changes in habitat structure resulting from colonization by C. racemosa on prey availability for predators, the importance of amphipods as a trophic resource in natural vegetated habitat was first
assessed, and later experiments were undertaken to assess the effects of the alien alga on predation by Thalassoma pavo of two dominant amphipods: Elasmopus brasiliensis (Gammaridea) and Caprella dilatata (Caprellidea). Laboratory experiments were conducted in separate aquaria with five vegetation habitat types: Halopteris scoparia, Jania rubens, C. racemosa without detritus, C. racemosa with detritus, Cymodocea nodosa, together with controls. The vegetation was first defaunated, and then 30 amphipods were introduced to each aquarium and
exposed to a single Thalassoma pavo individual for 1 h, after which the fish’s gut contents were examined. Consumption (per fish per hour) of caprellids (11.7 ± 1.4)
was higher overall than that of gammarids (8.7 ± 1.5) and likely reflects different microhabitat use by amphipods, which affects
susceptibility to predators. Consumption of amphipods also varied by habitat type. The highest predation rate was found in
the C. nodosa habitat (12.7 ± 2.19) and the lowest in the C. racemosa habitats with detritus (4.1 ± 1.78) and without detritus (5.2 ± 0.55), which did not differ. The pattern of predation across
habitats, however, was similar for both caprellid and gammarid amphipods, indicating a more general effect of habitat on amphipod
predation. Our findings showed that invasive species such as C. racemosa can decrease feeding by predators such as T. pavo. Changes in predator–prey interactions could have consequences for food web support in the Mediterranean. 相似文献