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991.
María Paz-Zulueta Javier Llorca Raquel Sarabia-Lavín Francisco Bolumar Luis Rioja Abraham Delgado Miguel Santibá?ez 《PloS one》2015,10(3)
Background and Aim
Literature evaluating association between neonatal morbidity and immigrant status presents contradictory results. Poorer compliance with prenatal care and greater social risk factors among immigrants could play roles as major confounding variables, thus explaining contradictions. We examined whether prenatal care and social risk factors are confounding variables in the relationship between immigrant status and neonatal morbidity.Methods
Retrospective cohort study: 231 pregnant African immigrant women were recruited from 2007–2010 in northern Spain. A Spanish population sample was obtained by simple random sampling at 1:3 ratio. Immigrant status (Spanish, Sub-Saharan and Northern African), prenatal care (Kessner Index adequate, intermediate or inadequate), and social risk factors were treated as independent variables. Low birth weight (LBW < 2500 grams) and preterm birth (< 37 weeks) were collected as neonatal morbidity variables. Crude and adjusted odds ratios (OR) were estimated by unconditional logistic regression with 95% confidence intervals (95% CI).Results
Positive associations between immigrant women and higher risk of neonatal morbidity were obtained. Crude OR for preterm births in Northern Africans with respect to nonimmigrants was 2.28 (95% CI: 1.04–5.00), and crude OR for LBW was 1.77 (95% CI: 0.74–4.22). However, after adjusting for prenatal care and social risk factors, associations became protective: adjusted OR for preterm birth = 0.42 (95% CI: 0.14–1.32); LBW = 0.48 (95% CI: 0.15–1.52). Poor compliance with prenatal care was the main independent risk factor associated with both preterm birth (adjusted OR inadequate care = 17.05; 95% CI: 3.92–74.24) and LBW (adjusted OR inadequate care = 6.25; 95% CI: 1.28–30.46). Social risk was an important independent risk factor associated with LBW (adjusted OR = 5.42; 95% CI: 1.58–18.62).Conclusions
Prenatal care and social risk factors were major confounding variables in the relationship between immigrant status and neonatal morbidity. 相似文献992.
Carreira RS Miyamoto S Di Mascio P Gonçalves LM Monteiro P Providência LA Kowaltowski AJ 《Journal of bioenergetics and biomembranes》2007,39(4):313-320
This study tests the hypothesis that ischemic preconditioning (IP) changes fatty acid (FA)-dependent uncoupling between mitochondrial
respiration and oxidative phosphorylation. We found that IP does not alter mitochondrial membrane integrity or FA levels,
but enhances membrane potential decreases when FA are present, in an ATP-sensitive manner. FA hydroperoxides had equal effects
in control and preconditioned mitochondria, and GTP did not abrogate the IP effect, suggesting uncoupling proteins were not
involved. Conversely, thiol reductants and atractyloside, which inhibits the adenine nucleotide translocator, eliminated the
differences in responses to FA. Together, our results suggest that IP leads to thiol oxidation and activation of the adenine
nucleotide translocator, resulting in enhanced FA transport and mild mitochondrial uncoupling. 相似文献
993.
Jordi Viñas Ana Gordoa Raquel Fernández-Cebrián Carles Pla Ünal Vahdet Rosa M. Araguas 《Reviews in Fish Biology and Fisheries》2011,21(3):527-541
The Atlantic bluefin tuna (Thunnus thynnus) is an extraordinary fish that has amazed humanity since ancient times. However, the continuous overexploitation of this
fishery, particularly in the Mediterranean Sea, could result in a total collapse of this resource. Currently, this species
is managed as two stocks: Western Atlantic and Mediterranean-Eastern Atlantic, with a recognized genetic differentiation between
them. On the other hand, the population structure within the Mediterranean Sea is still unclear. The biological data supports
the idea of two separate populations in the eastern and western Mediterranean basins. However, nuclear microsatellite and
mitochondrial DNA (mtDNA) analyses of two samples representative of these two basins result in a lack of heterogeneity. A
comparison of these results with previously published studies reveals some discrepancies. We have compared 59 genetic differentiation
tests that include samples within the Mediterranean. Of these, about 60% gave significant differentiation while the remaining
40% were non-significant. But, when only nuclear-based loci were considered, genetic differentiation was detected in up to
73% of the cases with an average significant F
ST
of only 0.018, whereas the average significant F
ST
of the mtDNA-based studies was significantly higher (0.029). However, in some cases, it is difficult to reconcile the biology
of the species with the results suggesting genetic differentiation. In conclusion, although it is not yet possible to reach
a definitive conclusion about the population structure, but considering all biological and genetic data, we suggest an independent
management approach for each basin to avoid the impact of a type II error that could lead to the possible loss of the regional
subpopulations. 相似文献
994.
Eleonora Regueira María Florencia Scaia María Clara Volonteri Nora Raquel Ceballos 《Journal of morphology》2013,274(3):331-343
The interrenal gland of anurans synthesizes the steroids aldosterone and corticosterone, but it is unknown whether these hormones are synthesized by the same cell type. In this work, we aim to elucidate whether there are different steroidogenic cell types and whether they have specific regionalization in the interrenal gland of the male toad Rhinella arenarum. We characterized all cell types using histological, immuhistochemical, and histochemical methods as well as transmission electron microscopy. Furthermore, we evaluated the organization of the cell types in the gland and anteroposterior variations in the synthesis of the steroids. We found evidence of five cell types: two morphologically different steroidogenic cells, type 1: polyhedral cells tightly attached to each other that have spherical euchromatic nuclei and type 2: retracted cells loosely attached to each other that have oval heterochromatic nuclei. Cell type 2 is mainly observed in the inner zone of the gland. In addition, we observed two types of chromaffin cells, called type 3 and 4 cells, randomly distributed throughout the interrenal gland, as well as type 5 cells, recognized as summer cells. Morphometric analyses of the cell types in the anterior and posterior zones of the interrenal showed that the ratio “area of type 2 cells/total interrenal area” is significantly lower in the posterior zone. In vitro incubations showed that the posterior portion of the gland produces significantly higher amounts of both corticosterone and aldosterone. Overall, our results suggest that the type 2 cells are less active to synthesize both aldosterone and corticosterone, compared to type 1 cells. Unlike most previous reports on the interrenal gland of anurans, in R. arenarum there is a zonation of the steroidogenic cell types, which implies that the organ is not anteroposterior or dorsoventrally homogeneous. © J. Morphol., 2013. © 2012 Wiley Periodicals, Inc. 相似文献
995.
Soili Stenroos Raquel Pino-Bodas Teuvo Ahti 《Cladistics : the international journal of the Willi Hennig Society》2019,35(5):603-603
A new generic name, Rexiella, is published to replace the recently published name Rexia S. Stenroos, Pino-Bodas and Ahti, which turned out to be an illegitimate later homonym of the cyanobacterial genus Rexia D. A. Casamatta, S. R. Gomez and J. R. Johansen. 相似文献
996.
Silvia Sayuri Mandai Raquel Corrêa Buranelli Christoph D. Schubart 《Marine Biology Research》2018,14(6):565-580
The hermit crab Calcinus tibicen has an extensive distribution along the coasts of the western Atlantic Ocean, from the USA to southern Brazil. The present study aimed to test the hypothesis of the presence of phylogeographic structure of C. tibicen throughout its distribution, evaluating the genetic and morphological variabilities of the species. The molecular data, genetic diversity and demographic history were inferred from 16 different localities for the mitochondrial genes cytochrome oxidase subunit I (COI) (75 specimens) and 16S rRNA (20). The morphological information was based on 99 individuals from the same 16 localities. Results were obtained by the construction of haplotype networks and a phylogenetic tree, an Analysis of Molecular Variance (AMOVA), Tajima’s D and Fu’s Fs tests, pairwise mismatch distributions under the sudden expansion model, and by estimating divergence times. The haplotype networks show the existence of two genetically well-defined groups that do not share haplotypes. The phylogenetic tree and the matrix of genetic distances suggest lack of gene between North and South Atlantic groups, also corroborated by AMOVA for the COI gene. The genetic distance can be attributed to at least two ecological factors: the existence of a physiological barrier caused by the Amazon River freshwater plume, and the effect of the bifurcation of the westerly flowing South Atlantic oceanic currents creating a gap along the Brazilian coastline. Demographic history analyses suggest that C. tibicen experienced population expansion, probably after the Amazon River changed its direction. Despite the molecular evidence for the existence of a phylogeographic structure, no morphological pattern for each genetic group was observed. Therefore, based on the described molecular differences and the ecological and historical factors suggested, the question arises whether a cryptic species should be recognized for some of the populations of C. tibicen. 相似文献
997.
Lindomar A. Lerin Raquel A. Loss Daniela Remonatto Mara Cristina Zenevicz Manuela Balen Vendelino Oenning Netto Jorge L. Ninow Cláudia M. Trentin J. Vladimir Oliveira Débora de Oliveira 《Bioprocess and biosystems engineering》2014,37(12):2381-2394
The named “green chemistry” has been receiving increasing prominence due to its environmentally friendly characteristics. The use of enzymes as catalysts in processes of synthesis to replace the traditional use of chemical catalysts present as main advantage the fact of following the principles of the green chemistry. However, processes of enzymatic nature generally provide lower yields when compared to the conventional chemical processes. Therefore, in the last years, the ultrasound has been extensively used in enzymatic processes, such as the production of esters with desirable characteristics for the pharmaceutical, cosmetics, and food industry, for the hydrolysis and glycerolysis of vegetable oils, production of biodiesel, etc. Several works found in the open literature suggest that the energy released by the ultrasound during the cavitation phenomena can be used to enhance mass transfer (substrate/enzyme), hence increasing the rate of products formation, and also contributing to enhance the enzyme catalytic activity. Furthermore, the ultrasound is considered a “green” technology due to its high efficiency, low instrumental requirement and significant reduction of the processing time in comparison to other techniques. The main goal of this review was to summarize studies available to date regarding the application of ultrasound in enzyme-catalyzed esterification, hydrolysis, glycerolysis and transesterification reactions. 相似文献
998.
The developing forelimb is patterned along the proximal–distal and anterior–posterior axes by opposing gradients of retinoic acid and fibroblast growth factors and by graded sonic hedgehog signaling, respectively. However, how coordinated patterning along both axes is accomplished with temporal precision remains unknown. The limb molecular oscillator hairy2 was recently shown to be a direct readout of the combined signaling activities of retinoic acid, fibroblast growth factor and sonic hedgehog in the limb mesenchyme. Herein, an integrated time-space model is presented to conciliate the progress zone and two-signal models for limb patterning. We propose that the limb clock may allow temporal information to be decoded into positional information when the distance between opposing signaling gradients is no longer sufficient to provide distinct cell fate specification. 相似文献
999.
The material of Rotundomys (Rodentia, Cricetinae) from the Late Miocene fossiliferous complex of Cerro de los Batallones (Madrid, Spain) is described and compared with all species currently placed in the genera Rotundomys and Cricetulodon. Both the morphology and size variation encompassed in the collection of specimens from Batallones suggest they belong to a single taxon different from the other known species of these genera. A new species Rotundomys intimus sp. nov. is, therefore, named for it. A cladistic analysis, which is the first ever published concernig these taxa, has been conducted to clear up the phylogenetic position of the new species. Our results suggest that Rotundomys intimus sp. nov. inserts between R. mundi and R. sabatieri as a relatively primitive taxon inside the clade Rotundomys. The new taxon is more derived than R. mundi in having a transversal connection between the metalophulid and the anterolophulid on some m1 but more primitive than R. sabatieri and the most evolved species of Rotundomys (R. montisrotuni +R.bressanus) in its less developed lophodonty showing distinct cusps, shallower valleys, and the presence of a subdivided anteroloph on the M1. The species of Cricetulodon do not form a monophyletic group. As a member of Rotundomys, Rotundomys intimus sp. nov. is more derived than all of these taxa in its greater lophodonty and the complete loss of the anterior protolophule, mesolophs, and mesolophids. 相似文献
1000.