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101.
There is growing interest in the development and optimization of bioremediation processes to deal with environments with high salinity that are contaminated with aromatic compounds. To estimate the diversity of moderately halophilic bacteria that could be used in such processes, enrichments were performed based on growth with a variety of aromatic compounds including phenol as a model pollutant. A group of bacteria that were able to grow over a wide range of salt concentrations were isolated, with the majority of these assigned to the genus Halomonas using phenotypic features and 16S rRNA sequences comparison. PCR amplification with degenerate primers revealed the presence in these isolates of genes encoding ring-cleaving enzymes in the beta-ketoadipate pathway for aromatic catabolism: catechol 1,2-dioxygenase and protocatechuate 3,4-dioxygenase. Furthermore, the activity of these two enzymes was detected in the newly described species Halomonas organivorans. Together, these studies indicate that moderately halophilic bacteria have the potential to catabolize aromatic compounds in environments with high salinity. 相似文献
102.
103.
Heymann Eckhard W. Encarnación C. Filomeno Canaquin Y. José E. 《International journal of primatology》2002,23(1):191-201
We conducted a short survey of primates along the Río Curaray in the northern Peruvian Amazon, emphazing rare, threatened or little known species. Contrary to Thorington, (Thorington, R. W., Jr., 1988, Am. J. Primatol. 15:367–371), we found no evidence for sympatry between Saguinus tripartitus and Saguinus fuscicollis, with the former being restricted to the north bank and the latter to the south bank of the Río Curaray. The Curaray also separates two species of Pithecia. The height above ground at which species were encountered increased with body size, providing evidence for vertical stratification within the primate community. The Curaray area still has rich primate diversity compared to other areas in the northern Peruvian Amazon, even though larger species, such as the spider monkeys, are hunted. 相似文献
104.
Sheida Azizi Mohammad Ali Nematollahi Bagher Mojazi Amiri Emilio J. Vélez Esmail Lutfi Isabel Navarro Encarnación Capilla Joaquim Gutiérrez 《PloS one》2016,11(1)
Optimizing aquaculture production requires better knowledge of growth regulation and improvement in diet formulation. A great effort has been made to replace fish meal for plant protein sources in aquafeeds, making necessary the supplementation of such diets with crystalline amino acids (AA) to cover the nutritional requirements of each species. Lysine and Leucine are limiting essential AA in fish, and it has been demonstrated that supplementation with them improves growth in different species. However, the specific effects of AA deficiencies in myogenesis are completely unknown and have only been studied at the level of hepatic metabolism. It is well-known that the TOR pathway integrates the nutritional and hormonal signals to regulate protein synthesis and cell proliferation, to finally control muscle growth, a process also coordinated by the expression of myogenic regulatory factors (MRFs). This study aimed to provide new information on the impact of Lysine and Leucine deficiencies in gilthead sea bream cultured myocytes examining their development and the response of insulin-like growth factors (IGFs), MRFs, as well as key molecules involved in muscle growth regulation like TOR. Leucine deficiency did not cause significant differences in most of the molecules analyzed, whereas Lysine deficiency appeared crucial in IGFs regulation, decreasing significantly IGF-I, IGF-II and IGF-IRb mRNA levels. This treatment also down-regulated the gene expression of different MRFs, including Myf5, Myogenin and MyoD2. These changes were also corroborated by a significant decrease in proliferation and differentiation markers in the Lysine-deficient treatment. Moreover, both Lysine and Leucine limitation induced a significant down-regulation in FOXO3 gene expression, which deserves further investigation. We believe that these results will be relevant for the production of a species as appreciated for human consumption as it is gilthead sea bream and demonstrates the importance of an adequate level of Lysine in fishmeal diet formulation for optimum growth. 相似文献
105.
UV responses of Lolium perenne raised along a latitudinal gradient across Europe: a filtration study
Comont D Martinez Abaigar J Albert A Aphalo P Causton DR Figueroa FL Gaberscik A Llorens L Hauser MT Jansen MA Kardefelt M de la Coba Luque P Neubert S Núñez-Olivera E Olsen J Robson M Schreiner M Sommaruga R Strid A Torre S Turunen M Veljovic-Jovanovic S Verdaguer D Vidovic M Wagner J Winkler JB Zipoli G Gwynn-Jones D 《Physiologia plantarum》2012,145(4):604-618
Lolium perenne (cv. AberDart) was grown at 14 locations along a latitudinal gradient across Europe (37-68°N) to study the impact of ultraviolet radiation (UV) and climate on aboveground growth and foliar UV-B absorbing compounds. At each location, plants were grown outdoors for 5 weeks in a replicated UV-B filtration experiment consisting of open, UV-B transparent (cellulose diacetate) and UV-B opaque (polyester) environments. Fourier transform-infrared spectroscopy was used to compare plant metabolite profiles in relation to treatment and location. UV radiation and climatic parameters were determined for each location from online sources and the data were assessed using a combination of anova and multiple regression analyses. Most of the variation in growth between the locations was attributable to the combination of climatic parameters, with minimum temperature identified as an important growth constraint. However, no single environmental parameter could consistently account for the variability in plant growth. Concentrations of foliar UV-B absorbing compounds showed a positive trend with solar UV across the latitudinal gradient; however, this relationship was not consistent in all treatments. The most striking experimental outcome from this study was the effect of presence or absence of filtration frames on UV-absorbing compounds. Overall, the study demonstrates the value of an European approach in studying the impacts of natural UV across a large latitudinal gradient. We have shown the feasibility of coordinated UV filtration at multiple sites but have also highlighted the need for open controls and careful interpretation of plant responses. 相似文献
106.
Background
Caviidae is a diverse group of caviomorph rodents that is broadly distributed in South America and is divided into three highly divergent extant lineages: Caviinae (cavies), Dolichotinae (maras), and Hydrochoerinae (capybaras). The fossil record of Caviidae is only abundant and diverse since the late Miocene. Caviids belongs to Cavioidea sensu stricto (Cavioidea s.s.) that also includes a diverse assemblage of extinct taxa recorded from the late Oligocene to the middle Miocene of South America (“eocardiids”).Results
A phylogenetic analysis combining morphological and molecular data is presented here, evaluating the time of diversification of selected nodes based on the calibration of phylogenetic trees with fossil taxa and the use of relaxed molecular clocks. This analysis reveals three major phases of diversification in the evolutionary history of Cavioidea s.s. The first two phases involve two successive radiations of extinct lineages that occurred during the late Oligocene and the early Miocene. The third phase consists of the diversification of Caviidae. The initial split of caviids is dated as middle Miocene by the fossil record. This date falls within the 95% higher probability distribution estimated by the relaxed Bayesian molecular clock, although the mean age estimate ages are 3.5 to 7 Myr older. The initial split of caviids is followed by an obscure period of poor fossil record (refered here as the Mayoan gap) and then by the appearance of highly differentiated modern lineages of caviids, which evidentially occurred at the late Miocene as indicated by both the fossil record and molecular clock estimates.Conclusions
The integrated approach used here allowed us identifying the agreements and discrepancies of the fossil record and molecular clock estimates on the timing of the major events in cavioid evolution, revealing evolutionary patterns that would not have been possible to gather using only molecular or paleontological data alone. 相似文献107.
Anthony B. Rylands Christian Matauschek Rolando Aquino Filomeno Encarnación Eckhard W. Heymann Stella de la Torre Russell A. Mittermeier 《Primates; journal of primatology》2011,52(1):41-39
A detailed understanding of the range of the golden-mantle tamarin, Saguinus tripartitus (Milne Edwards, 1878), in Amazonian Peru and Ecuador is of particular relevance, not only because it is poorly known but
also because it was on the basis of its supposed sympatry with the saddleback tamarin (S. fuscicollis lagonotus) that Thorington (Am J Primatol 15:367–371, 1988) argued that it is a distinct species rather than a saddleback tamarin subspecies, as was believed by Hershkovitz (Living
new world monkeys, vol I. The University of Chicago Press, Chicago, 1977). A number of surveys have been carried out since 1988 in the supposed range of S. tripartitus, in both Ecuador and Peru. Here we summarize and discuss these issues and provide a new suggestion for the geographic range
of this species; that is, between the ríos Napo and Curaray in Peru and extending east into Ecuador. We also review current
evidence for the distributions of Spix’s black-mantle tamarin (S. nigricollis nigricollis), Graells’ black-mantle tamarin (S. n. graellsi), and the saddleback tamarin (S. fuscicollis lagonotus), which are also poorly known, and examine the evidence regarding sympatry between them. We conclude that despite the existence
of a number of specimens with collecting localities that indicate overlap in their geographic ranges, the fact that the four
tamarin species are of similar size and undoubtedly very similar in their feeding habits militates strongly against the occurrence
of sympatry among them. 相似文献
108.
Frutos Carlos Marhuenda-Egea Rub��n Gons��lvez-��lvarez Encarnaci��n Mart��nez-Sabater Bel��n Lled�� Jorge Ten Rafael Bernabeu 《Metabolomics : Official journal of the Metabolomic Society》2011,7(2):247-256
We present here a new metabolomic methodology to predict embryo implantation ability in in vitro fertilization (IVF). In the
present study we have included a total of 23 patients scheduled for IVF. Embryos were selected to be transferred by using
morphological criteria on day 3 of in vitro culture. The relative amino acid concentrations in the embryo culture media were
analyzed by HPLC–MS and HPLC–MS/MS. 1H NMR metabolomic profiles were also obtained for the embryo culture media. Chemometric models were performed with SIMCA (soft
independent modeling of class analogy) for samples from both, non-pregnancy and pregnancy cycles. The metabolic differences
between the embryos, with pregnancy and non-pregnancy outcome, can be correlated with the relative amino acid concentrations
and with 1H NMR profiles. We used interval partial least square (iPLS) in order to identify the higher correlation between regions in
the 1H NMR spectra and the embryo implantation capability. The 1H NMR regions with higher correlation are between 1.2 and 0.5 ppm, that included the signals for cholesterol backbone –C(18)H3, –CH3 and CH2 groups of triglycerides, cholesterol compounds and phospholipids. Our results can allow building a quick, non invasive, useful
and feasible chemometric models in order to identify embryos with a high pregnancy rate and embryos unable to achieve successful
pregnancies. 相似文献
109.
Ines M. Barrio-Cantalejo Pablo Simón-Lorda Adoración Molina-Ruiz Fátima Herrera-Ramos Encarnación Martínez-Cruz Rosa Maria Bailon-Gómez Antonio López-Rico Patricia Peinado Gorlat 《Journal of bioethical inquiry》2013,10(1):103-114
Objective: To measure the stability of life-sustaining treatment preferences amongst older people and analyse the factors that influence stability. Design: Longitudinal cohort study. Setting: Primary care centres, Granada (Spain). Eighty-five persons age 65 years or older. Participants filled out a questionnaire with six contexts of illness (LSPQ-e). They had to decide whether or not to receive treatment. Participants completed the questionnaire at baseline and 18 months later. Results: 86 percent of the patients did not change preferences. Sex, age, marital status, hospitalisation, and self-perception of health and pain did not affect preferences. Morbidity and the death of a relative did. Conclusion: Stability of preferences of older persons in relation to end-of-life decisions seems to be more probable than instability. Some factors, such as the death of a relative or the increase in morbidity, can change preferences. These findings have implications for advance directives (ADs) and advance care planning. 相似文献
110.
Belén de la Hera Jezabel Varadé Marta García-Montojo José Ramón Lamas Ana de la Encarnación Rafael Arroyo Benjamín Fernández-Gutiérrez Roberto álvarez-Lafuente Elena Urcelay 《PloS one》2013,8(4)