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131.
Temperatures in two mature Polybia nests were measured to study the thermal conditions of nests. Temperatures in a Polybia paulista nest were measured when it had adult wasps (trial 1) and after the adult wasps were removed (trial 2), and temperatures in a P. occidentalis nest were measured when inhabited by adult wasps (trial 3). In each trial, C–C thermocouples were set at four points in the nest and at two points outside to discover the ambient and substratum temperatures. In trial 1, nest temperatures basically followed the ambient temperature, but during the day the nest temperatures were lower than the ambient temperature and this relationship was reversed during the night. The temperature fluctuation of the inner substratum points was smaller than that of the outer points. The trend of trial 2 was closely similar to that of trial 1, showing a virtual lack of thermal effects from the presence of adult wasps. In trial 3, the changing pattern in the P. occidentalis nest showed a trend similar to that in the P. paulista nest, but the inside temperatures rose quickly when the nest received direct sunlight in the morning. From these results, thermal characteristics in the Polybia nests are discussed in relation to the nest architecture and their geographical distribution.  相似文献   
132.
We present a detailed investigation of unfolded and partially folded states of a mutant apomyoglobin (apoMb) where the distal histidine has been replaced by phenylalanine (H64F). Previous studies have shown that substitution of His64, located in the E helix of the native protein, stabilizes the equilibrium molten globule and native states and leads to an increase in folding rate and a change in the folding pathway. Analysis of changes in chemical shift and in backbone flexibility, detected via [1H]-15N heteronuclear nuclear Overhauser effect measurements, indicates that the phenylalanine substitution has only minor effects on the conformational ensemble in the acid- and urea-unfolded states, but has a substantial effect on the structure, dynamics, and stability of the equilibrium molten globule intermediate formed near pH 4. In H64F apomyoglobin, additional regions of the polypeptide chain are recruited into the compact core of the molten globule. Since the phenylalanine substitution has negligible effect on the unfolded ensemble, its influence on folding rate and stability comes entirely from interactions within the compact folded or partly folded states. Replacement of His64 with Phe leads to favorable hydrophobic packing between the helix E region and the molten globule core and leads to stabilization of helix E secondary structure and overall thermodynamic stabilization of the molten globule. The secondary structure of the equilibrium molten globule parallels that of the burst phase kinetic intermediate; both intermediates contain significant helical structure in regions of the polypeptide that comprise the A, B, E, G, and H helices of the fully folded protein.  相似文献   
133.
The Mauritia flexuosa L.f. tree is of immense socioeconomic significance in the Brazilian Middle North Region for its manifold benefits, but mainly for its fruit. However, the potential of this species has still not been extensively studied. The objectives of this work were to study the phenotypic and genotypic correlations between the characteristics of the M. flexuosa fruits and to establish the direct and indirect effects of the secondary characteristics of the fruit on the pulp yield. Samples of ten fruits per genotype were gathered from four natural populations, from 240 different genotypes. These samples were assessed in terms of the fruit, almond and hull weights, equatorial and polar fruit diameters, and the fruit, almond and pulp, volumes, as well as the pulp yield. The genotypic correlations showed greater magnitude, higher than the phenotypic correlations, and both were significant and revealed equal signs. The indirect selection of the M. flexuosa genotypes with greater fruit weight and almond volume favored the increase in the pulp yield in this fruit species.  相似文献   
134.
Bamboos play an important role in forest dynamics, but management strategies are needed to avoid monodominance. Understanding how climate change would influence the geographic distribution of bamboos could provide management tools for habitat conservation, as well as prevent the expansion of this group. We investigated the distribution patterns of Merostachys species that are endemic to the Brazilian Atlantic Forest, under current and future climate scenarios. We obtained occurrence records based on field collection, herbaria data and online databases. We used the Maxent algorithm to model potential distribution. Future scenarios considered the IPCC forecasted climate for 2070. Our models showed that a reduction in suitable areas for Merostachys species will likely occur, but the existence of suitable areas under climate changes in the Brazilian Atlantic Forest indicates climatic stability in some areas of occurrence of these species in their richness center. Since the fact that in places with local dominance of woody bamboos there is a decrease in the diversity of other plant species, the occurrence of Merostachys throughout the suitable areas may represent risks to biodiversity conservation. Investigations of the synergistic effects of climate change and the local dominance of woody bamboos are required. Therefore, management measures may be very important to control the occurrence of woody bamboos in the Brazilian Atlantic Forest, mainly in climatically stable areas.  相似文献   
135.
BackgroundGuyana is one of four countries in the Latin American Region where lymphatic filariasis (LF) remains endemic. In preparation for the introduction of a new triple drug therapy regimen (ivermectin, diethylcarbamazine, and albendazole (IDA)) in 2019, an acceptability study was embedded within sentinel site mapping in four regions to assess mass drug administration (MDA) coverage and compliance, acceptability, and perceptions about treatment and disease. The results from this survey would inform the rollout of IDA in Guyana in 2019.MethodsData collection for the study occurred in August 2019, using a validated questionnaire administered by trained enumerators. Across all regions, a total of 1,248 participants were sampled by the Filarial Mapping team. Four-hundred and fifty-one participants aged over 18 years were randomly selected for participation in an expanded acceptability questionnaire. All data were captured in Secure Data Kit (SDK).ResultsAcceptability was measured using a mean acceptability score. Unadjusted mean scores ranged from 24.6 to 29.3, with 22.5 as the threshold of acceptability. Regional variation occurred across many indicators of interest: self-rated understanding about LF, mechanisms of LF transmission, LF drug safety and history of treatment during MDA. Region IV (Georgetown) recorded higher knowledge about LF, but lower compliance and acceptability. Number of pills was not perceived as a concern.ConclusionAcceptability of MDA was good across all four regions under study. Results from this study set a baseline level for key indicators and acceptability, from which the acceptability of IDA can be measured. Regional variations across indicators suggest that localized approaches should be considered for social mobilization and MDA delivery to capture these contextual differences.  相似文献   
136.
The understanding of molecular mechanisms underlying host–pathogen interactions in plant diseases is of crucial importance to gain insights on different virulence strategies of pathogens and unravel their role in plant immunity. Among plant pathogens, Phytophthora species are eliciting a growing interest for their considerable economical and environmental impact. Plant infection by Phytophthora phytopathogens is a complex process coordinated by a plethora of extracellular signals secreted by both host plants and pathogens. The characterization of the repertoire of effectors secreted by oomycetes has become an active area of research for deciphering molecular mechanisms responsible for host plants colonization and infection. Putative secreted proteins by Phytophthora species have been catalogued by applying high-throughput genome-based strategies and bioinformatic approaches. However, a comprehensive analysis of the effective secretome profile of Phytophthora is still lacking. Here, we report the first large-scale profiling of P. plurivora secretome using a shotgun LC-MS/MS strategy. To gain insight on the molecular signals underlying the cross-talk between plant pathogenic oomycetes and their host plants, we also investigate the quantitative changes of secreted protein following interaction of P. plurivora with the root exudate of Fagus sylvatica which is highly susceptible to the root pathogen. We show that besides known effectors, the expression and/or secretion levels of cell-wall-degrading enzymes were altered following the interaction with the host plant root exudate. In addition, a characterization of the F. sylvatica root exudate was performed by NMR and amino acid analysis, allowing the identification of the main released low-molecular weight components, including organic acids and free amino acids. This study provides important insights for deciphering the extracellular network involved in the highly susceptible P. plurivora-F. sylvatica interaction.  相似文献   
137.
We previously showed that patients with temporal lobe epilepsy (TLE) present an increased expression of angiotensin II (AngII) AT1 and AT2 receptors in the hippocampus, supporting the idea of an upregulation of renin-angiotensin system (RAS) in this disease. This study aimed to verify the relationship between the RAS and TLE during epileptogenesis. Levels of the peptides angiotensin I (AngI), angiotensin II (AngII) and angiotensin 1-7 (Ang 1-7), were detected by HPLC assay. Angiotensin AT1 and AT2 receptors, Mas mRNA receptors and angiotensin converting enzyme (ACE), tonin and neutral endopeptidase (NEP) mRNA were also quantified at the hippocampus of Wistar rats by real time PCR, during acute (n=10), silent (n=10) and chronic (n=10) phases of pilocarpine-induced epilepsy. We observed an increased peptide level of Ang1-7 into acute and silent phases, decreasing importantly (p≤0.05) in the chronic phase, suggesting that AngI may be converted into Ang 1-7 by NEP, which is present in high levels in these periods. Our results also showed increased peptide level of AngII in the chronic phase of this model. In contraposition, the ACE expression is reduced in all periods. These data suggest that angiotensinogen or AngI may be cleaved to AngII by tonin, which showed increased expression in all phases. We found changes in AT1, AT2 and Mas mRNA receptors levels suggesting that Ang1-7 could act at Mas receptor during the silent period. Herein, we demonstrated for the first time, changes in angiotensin-related peptides, their receptors as well as the releasing enzymes in the hippocampus of rats during pilocarpine-induced epilepsy.  相似文献   
138.
The biodistribution of radiopharmaceuticals used in diagnostic imaging can be altered by a wide variety of factors. We studied the effect of murine B16F10 melanoma on the biodistribution in mice of 99mTechnetium-methylenediphosphonic acid (99mTc-MDP). Viable B16-F10 cell lines (1 x 10(5)) were inoculated subcutaneously in the dorsal region of 8-12 week-old male isogenic C57BV/6j mice. 14-16 days after inoculation, 99mTc-MDP was injected in the ocular plexus and after 0.5 hr the animals were rapidly sacrificed. The organs and tumor were isolated, the mass determined and the percentage per gram of injected activity (%ATI/g) calculated. The results shown that the %ATI/g:i/ has not been altered in inguinal lymph nodes, prostate, pancreas, testis, seminal vesicle, bladder, kidney, stomach, small intestine, spleen, thymus, heart, lung, brain and muscle; but ii/ significantly decreased in thyroid, bone, blood and liver. In conclusion, the B16F10 melanoma can alter the 99mTc-MDP uptakes in some organs.  相似文献   
139.
Brazil is the leading global exporter of soccer players, with approximately 2,000 international transfers to different clubs per year. Although Brazilian players compete in the most prestigious soccer leagues worldwide, the habitual training methods, strategies, and routines of Brazilian soccer strength and conditioning coaches (SCCs) are undocumented. This study used a standard online survey to collect and characterize the strength and conditioning practices of Brazilian soccer SCCs. Forty-nine SCCs (age: 40.4 ± 7.5 years; professional experience: 15.3 ± 7.5 years) working in Brazilian professional soccer teams participated in this study. The survey consisted of eight sections: 1) background information; 2) muscular strength-power development; 3) speed training; 4) plyometrics; 5) flexibility training; 6) physical testing; 7) technology use; and 8) programing. Results indicated that training and testing practices of Brazilian SCCs are strongly affected by the congested fixture schedules, extensive traveling distances, and socio-economic disparities between different regions of the country. We describe all these different strategies and methods in detail, providing a comprehensive view and a critical examination of Brazilian soccer strength and conditioning practices. Brazilian SCCs and professional soccer organizations can use the findings from this study to develop training strategies and customize education programs. Practitioners from other countries can use this information to design training programs closely tailored to the background of Brazilian athletes, which may support their adaptation to different competitive scenarios and game demands, such as those found in the most important soccer leagues worldwide.  相似文献   
140.
Abstract A study was carried out to evaluate the potential intestinal toxicity of 188 samples of Vibrio cholerae non-01 isolated from seawater found along the beaches of Rio de Janeiro city. Three different assays were carried out involving: (a) detection of vascular permeability factor (PF) in guinea pigs (together with assessment of two culture media for production of the toxin); (b) intestinal fluid accumulation (FA) in suckling mice; and (c) detection of haemolysin. The results demonstrated that both culture media gave a similar level of performance. In the animal assays, 43% of the samples induced PF in guinea pigs, 28.7% caused intestinal fluid accumulation in suckling mice, and 63.28% contained haemolysin. Only 4.25% of the samples gave positive results in all three tests.  相似文献   
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