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31.
To better understand the relation between coastal areas and their influence on social and economic conditions of municipalities, a set of indexes were developed to characterize coastal Mexico with an interdisciplinary approach. The composite of these bio-physical, social and economic indexes is referred to as an “integrated coastal orientation index”. Coastal characteristics should be taken into account in the coastal management policy formulation of a given region, and this index can be used to identify key areas for environmental protection or economic development at a national level. The results suggest that municipalities must manage their coastal jurisdictions, a large and diverse array of coastal space and ecosystems, medium to weak spatial demographics and settlement structures, infrastructure to improve quality of life, an overall low coastal population income, and various coastal activities. Spatial heterogeneity along the littoral zone in the coastal orientation led us to conduct a state analysis. We discuss these values and identify five highly coastal-orientated states in the extremes of the country. The development of this tool could help to pin-point different types of key areas within the regions studied and provide a tool to guide regional priorities. As an example, using a combination of extreme values of bio-physical, social and economic indexes was used to identify specific municipalities as candidates for environmental protection and others as areas where development can continue. Choices of indexes are discussed, and the relative importance given to each component of the coastal orientation (rather bio-physical, social and/or economic) will define the course of the coast's development and its sustainability.  相似文献   
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Lectin histochemistry study in the human vas deferens   总被引:1,自引:0,他引:1  
The oligosaccharide sequences of glycoconjugates in the normal human vas deferens and the nature of the saccharide linkage were studied by lectin histochemistry. The cytoplasm of all epithelial cell types (principal cells, basal cells, and mitochondria-rich cells) and luminal contents reacted positively with WGA, MAA, PNA, DSA, LTA, UEA-I, AAA, and ConA. The reaction was more intense in the stereocilia of principal cells. Cytoplasmic staining was diffuse except for PNA and DSA labeling which was limited to the apical cytoplasm and stereocilia of columnar cells. The cytoplasm of all cell types also reacted diffusely with HPA, although staining was weak and was not observed in the stereocilia. Positive reaction with SBA only was encountered in the stereocilia of principal cells. SNA, LTA, and DBA were unreactive. GNA-labeling showed a granular distribution in the supranuclear cytoplasm of columnar epithelial cells. Reactions with MAA, PNA, DSA, AAA, HPA and SBA disappeared after the -elimination reaction. Reactions with WGA and UEA-I decreased after -elimination or Endo-F digestion. Reactions with ConA and GNA were suppressed by Endo-F digestion. Reactions with PNA, HPA, and SBA increased after desialylation. Of all the lectins that label the luminal contents of the vas deferens, only UEA-I was not found in the luminal contents of seminiferous tubules and epididymis and, thus, this lectin would probably bind to glycoproteins secreted by the vas deferens. The chemical treatments used suggest that this secretion contains fucose residues located in both N- and O-linked oligosaccharides. The other lectins may label secreted proteins, but also structural proteins or proteins reabsorbed from the luminal fluid. The lectin- binding pattern of mitochondria-rich cells in the vas deferens differed from that found in the epididymis.  相似文献   
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After some 70 years of debate on density-dependent regulation of animal populations, there is still poor understanding of where spatial and temporal density dependence occurs. Clearly defining the portion of the population that shapes density-dependent patterns may help to solve some of the ambiguities that encircle density dependence and its patterns. In fact, individuals of the same species and population can show different dynamics and behaviors depending on their locations (e.g., breeding vs. dispersal areas). Considering this form of intrapopulation heterogeneity may improve our understanding of density dependence and population dynamics in general. We present the results of individual-based simulations on a metapopulation of the Spanish imperial eagle Aquila adalberti. Our results suggest that high rates of floater mortality within settlement areas can determine a shift in the classical relationship (from negative to positive) between the fecundity (i.e., fledglings per pair) and density (i.e., number of pairs) of the breeding population. Finally, we proved that different initial conditions affecting the breeder portion of the population can lead to the same values of fecundity. Our results can represent a starting point for new and more complex approaches studying the regulation of animal populations, where the forgotten and invisible component--the floater--is taken into account.  相似文献   
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Journal of Physiology and Biochemistry - Fatty acids (FAs) are known to participate in body inflammatory responses. In particular, saturated FAs such as palmitic acid (PA) induce inflammatory...  相似文献   
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This article presents the evolution of culture broth rheological properties during monoxenic cultures of Steinernema carpocapsae in cylindrical bottles agitated orbitally. Rheological properties were evaluated in simple-shear flow conditions and were well-modeled by the Ostwald-de Waele model. Rheological properties varied from slightly dilatant, n = 1.2 (-), to moderately pseudoplastic flow behavior, n = 0.6 (-). Nematode concentrations increased from 750 +/- 190 to 130 900 +/- 6900 nematodes/mL, and the apparent viscosity (eta(a)) evolved from 4.5 +/- 0.7 to 46.6 +/- 3.2 mPa.s during the fermentations. Rheological behavior did not appear to be strongly influenced by nematode number and/or its stage of development; however, the release of substances from the decomposition of nematode cadavers appeared to be of great importance. Among the different developmental stages of the nematodes, only juveniles of the first stage (J1) were highly susceptible to the shearing conditions tested (shear stress, tau(r)()(theta), from 0.9 to 3.5 Pa during periods of 80-100 min), resulting in the viability loss of 85% of J1 nematodes.  相似文献   
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The regulation of glutamine synthetase (EC 6.3.1.2) from Prochlorococcus was previously shown to exhibit unusual features: it is not upregulated by nitrogen starvation and it is not inactivated by darkness (El Alaoui et al. (2001) Appl Environ Microbiol 67: 2202-2207). These are probably caused by adaptations to oligotrophic environments, as confirmed in this work by the marked decrease in the enzymatic activity when cultures were subjected to iron or phosphorus starvation. In order to further understand the adaptive features of ammonium assimilation in this cyanobacterium, glutamine synthetase was purified from two Prochlorococcus strains: PCC 9511 (high-light adapted) and SS120 (low-light adapted). We obtained approximately 100-fold purified samples of glutamine synthetase electrophoretically homogeneous, with a yield of approximately 30%. The estimated molecular mass of the subunits was roughly the same for both strains: 48.3 kDa. The apparent Km constants for the biosynthetic activity were 0.30 mM for ammonium, 1.29 mM for glutamate and 1.35 mM for ATP; the optimum pH was 8.0. Optimal temperature was surprisingly high (55 degrees C). Phylogenetic analysis of glnA from three Prochlorococcus strains (MED4, MIT9313 and SS120) showed they group closely with marine Synechococcus isolates, in good agreement with other studies based on 16 S RNA sequences. All of our results suggest that the structure and kinetics of glutamine synthetase in Prochlorococcus have not been significantly modified during the evolution within the cyanobacterial radiation, in sharp contrast with its regulatory properties.  相似文献   
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Possibilities to create an efficient network of areas for the conservation of Iberian dung-beetle biodiversity were investigated. Data were taken from BANDASCA, a 15,740 record dung-beetle database with information for 101,996 specimens. The greatest species richness and phylogenetic diversity are found in the Iberian Central System cordilleras, while those of range-size rarity are in the southernmost corner of the Iberian Peninsula and in the coastal plains of the Guadalquivir basin. Additionally, broad regional score trends of these variables reach a maximum in a smaller northeastern, and a larger southeastern region (Baetic and sub-Baetic mountains). Major Central and Southern Spain dung-beetle hotspots contain many of the UTM grid cells which delimit the near-minimum-set of areas hosting maximum dung-beetle biodiversity scores. They are viewed as the nucleus of a potential network of reserves. A UTM grid cell (30TXK1) where Onthophagus albarracinus, an endemic and demographically rare species inhabits the Sierra of Albarracín and Montes Universales, was detected as an irreplaceable area. Because of recent land use changes and rapid human-induced habitat transformation threatening dung-beetle fauna, caution should be taken not to recommend an in memoriam network of areas no longer hosting a fauna extinct today. The abandoning of traditional herding management in Europe threatens the preservation of grasslands where dung-feeding beetles play a major ecological role in maintaining pasture quality and livestock health. A return to more traditional herding methods would require stable dung-beetle populations. Any insect conservation planning in Spain would benefit from more biogeographical information for other insect groups.  相似文献   
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