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221.
Two models of the human infant's caretaking requirements—the continuous care and contact model and the caretaker-child strategy model—are discussed in terms of the caretaking practices observed among the Efe (Pygmies) of northeastern Zaire. The Efe1 engage in a system of multiple care which begins at birth and continues through at least the first 18 weeks of life. An important aspect of this care includes being suckled by lactating and nonlactating women. The data suggest that the continuous care and contact model is too rigid a formulation of the infant's caretaking environment, and lend support to the strategic model. Efe caretaking practices are discussed in terms of the cultural, ecological, and physiological constraints acting on these people. 相似文献
222.
Mógor Atila Francisco Amatussi Juliana Oliveira Mógor Gilda Gemin Luiz Gabriel 《Journal of applied phycology》2021,33(3):1905-1913
Journal of Applied Phycology - The development of new natural biostimulant sources for a sustainable agriculture is a strategic issue aiming to improve the healthy food production. In this sense,... 相似文献
223.
John A. Lawson Edward T. Uyeno John Nienow Gilda H. Loew Lawrence Toll 《Life sciences》1984,34(21):2007-2013
A number of β-carboline analogs have been obtained or synthesized, and their receptor affinities and antagonist activities determined. The choice of analogs was made in order to explore the importance of the N9-H, the aromatic nitrogen and the C3-ester moiety for high-receptor affinity and antagonist activity of this class of benzodiazepine antagonist. Among the analogs investigated, we describe the properties of 3-cyano-β-carboline (), the first potent β-carboline antagonist without a carbonyl at the C3-position.The results obtained indicate: (1) Specific interactions of the C3-substituent with key cationic receptor sites rather than electron-withdrawing properties are important for high-receptor affinity and antagonist activity. (2) Specific in-plane interactions of the atomatic nitrogen with a cationic receptor site, rather than stacking with neutral aromatic residues of the receptor are also important for high affinity and antagonist activity. (3) While the presence of an N9H enhances receptor affinity, interaction with an anionic receptor site does not appear essential for antagonist activity. 相似文献
224.
Daniela Montorio Gilda Cennamo Feliciana Menna Piero Donna Pasquale Napolitano Maria Angelica Breve Ugo Fiore Giovanni Cennamo Nicola Rosa 《Journal of biophotonics》2020,13(10)
The aim of this study is to evaluate corneal epithelial thickness (CET), corneal densitometry (CD) in 84 myopic eyes (57 patients) more than 22 years after photorefractive keratectomy, using anterior segment‐optical coherence tomography (AS‐OCT) and Scheimpflug imaging system. The CET was significantly higher in all operated eyes than in unoperated eyes in central sector. A statistically significant increase in CD in corneal anterior layer of central sector was shown in groups of operated eyes with greater ablation depth respect to unoperated eyes. While there was no significant difference in CD between the operated eyes groups with lower ablation depth and unoperated eyes. A significant trend toward higher values in anterior CD with deeper ablations in central sector was found. These noninvasive imaging techniques allow to better understand the corneal remodeling process after photoablation and to monitor the patients over time. 相似文献
225.
Alfredo Rodríguez Kaiyang Zhang Anniina Färkkilä Jessica Filiatrault Chunyu Yang Martha Velázquez Elissa Furutani Devorah C. Goldman Benilde García de Teresa Gilda Garza-Mayén Kelsey McQueen Larissa A. Sambel Bertha Molina Leda Torres Marisol González Eduardo Vadillo Rosana Pelayo William H. Fleming Alan D. D’Andrea 《Cell Stem Cell》2021,28(1):33-47.e8
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226.
In the context of the bay region, K-region and radical cation hypotheses for polycyclic aromatic carcinogens, molecular properties were calculated for fourteen methyl derivatives of benz[a]anthracene (BA) related to (1) intrinsic substrate reactivities towards activating and detoxifying metabolism and (2)-the stabilities of the putative carbocation ultimate carcinogens. Allvalence electron methods were used, avoiding the inherent difficulties found in the π-electron methods. The calculated substrate reactivities were found to predict major metabolites sucessfully, supporting the validity of their use in attempted correlations with observed carcinogenic potencies. Positive correlations were found between observed carcinogenic potencies and (1) the reactivities of the parent polycyclic aromatic hydrocarbons (PAH) towards the initial distal bay region epoxidation and (2) the stabilities of the diol epoxide carbocations. This latter correlation holds when both the methyl derivatives of BA and previously studied unsubstituted PAH are considered together, indicating its potential usefulness as a screening parameter for carcinogenic activity. 相似文献
227.
Eliza Bliss-Moreau Jacob H. Theil Gilda Moadab 《Journal of applied animal welfare science : JAAWS》2013,16(2):98-117
It is sometimes necessary for nonhuman primates to be restrained during biomedical and psychosocial research. Such restraint is often accomplished using a “primate chair.” This article details a method for training adult rhesus macaques to cooperate with a chair restraint procedure using positive and negative reinforcement. Successful training was accomplished rapidly in approximately 14 training days. The success of this training technique suggests that this method represents a refinement to traditional techniques. Further, this method worked effectively for animals previously deemed unfit for traditional pole-and-collar training. 相似文献
228.
João N. de Almeida Júnior Karim Y. Ibrahim Gilda M. B. Del Negro Evandro D. Bezerra Amaro N. Duarte Neto Marjorie V. Batista Rinaldo F. Siciliano Mauro C. Giudice Adriana L. Motta Flávia Rossi Ligia C. Pierrotti Maristela P. Freire Marcelo Bellesso Juliana Pereira Edson Abdala Gil Benard 《Mycopathologia》2016,181(1-2):125-129
229.
Jason Bosch Gilda Varliero John E. Hallsworth Tiffany D. Dallas David Hopkins Beat Frey Weidong Kong Pedro Lebre Thulani P. Makhalanyane Don A. Cowan 《Environmental microbiology》2021,23(11):6377-6390
The loss of cellular water (desiccation) and the resulting low cytosolic water activity are major stress factors for life. Numerous prokaryotic and eukaryotic taxa have evolved molecular and physiological adaptions to periods of low water availability or water-limited environments that occur across the terrestrial Earth. The changes within cells during the processes of desiccation and rehydration, from the activation (and inactivation) of biosynthetic pathways to the accumulation of compatible solutes, have been studied in considerable detail. However, relatively little is known on the metabolic status of organisms in the desiccated state; that is, in the sometimes extended periods between the drying and rewetting phases. During these periods, which can extend beyond decades and which we term ‘anhydrobiosis’, organismal survival could be dependent on a continued supply of energy to maintain the basal metabolic processes necessary for critical functions such as macromolecular repair. Here, we review the state of knowledge relating to the function of microorganisms during the anhydrobiotic state, highlighting substantial gaps in our understanding of qualitative and quantitative aspects of molecular and biochemical processes in desiccated cells. 相似文献
230.
Maria G E Albuquerque Gilda Carvalho Caroline Kragelund Ana F Silva Maria T Barreto Crespo Maria A M Reis Per H Nielsen 《The ISME journal》2013,7(1):1-12
The microbial community of a fermented molasses-fed sequencing batch reactor (SBR) operated under feast and famine conditions for production of polyhydroxyalkanoates (PHAs) was identified and quantified through a 16 S rRNA gene clone library and fluorescence in situ hybridization (FISH). The microbial enrichment was found to be composed of PHA-storing populations (84% of the microbial community), comprising members of the genera Azoarcus, Thauera and Paracoccus. The dominant PHA-storing populations ensured the high functional stability of the system (characterized by high PHA-storage efficiency, up to 60% PHA content). The fermented molasses contained primarily acetate, propionate, butyrate and valerate. The substrate preferences were determined by microautoradiography-FISH and differences in the substrate-uptake capabilities for the various probe-defined populations were found. The results showed that in the presence of multiple substrates, microbial populations specialized in different substrates were selected, thereby co-existing in the SBR by adapting to different niches. Azoarcus and Thauera, primarily consumed acetate and butyrate, respectively. Paracoccus consumed a broader range of substrates and had a higher cell-specific substrate uptake. The relative species composition and their substrate specialization were reflected in the substrate removal rates of different volatile fatty acids in the SBR reactor. 相似文献