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61.
Ekué Marius RM Sinsin Brice Eyog-Matig Oscar Finkeldey Reiner 《Journal of ethnobiology and ethnomedicine》2010,6(1):1-14
Background
Changing lifestyles have recently caused a severe reduction of the gathering of wild food plants. Knowledge about wild food plants and the local environment becomes lost when plants are no longer gathered. In Central Europe popular scientific publications have tried to counter this trend. However, detailed and systematic scientific investigations in distinct regions are needed to understand and preserve wild food uses. This study aims to contribute to these investigations.Methods
Research was conducted in the hill country east of Graz, Styria, in Austria. Fifteen farmers, most using organic methods, were interviewed in two distinct field research periods between July and November 2008. Data gathering was realized through freelisting and subsequent semi-structured interviews. The culinary use value (CUV) was developed to quantify the culinary importance of plant species. Hierarchical cluster analysis was performed on gathering and use variables to identify culture-specific logical entities of plants. The study presented was conducted within the framework of the master's thesis about wild plant gathering of the first author. Solely data on gathered wild food species is presented here.Results
Thirty-nine wild food plant and mushroom species were identified as being gathered, whereas 11 species were mentioned by at least 40 percent of the respondents. Fruits and mushrooms are listed frequently, while wild leafy vegetables are gathered rarely. Wild foods are mainly eaten boiled, fried or raw. Three main clusters of wild gathered food species were identified: leaves (used in salads and soups), mushrooms (used in diverse ways) and fruits (eaten raw, with milk (products) or as a jam).Conclusions
Knowledge about gathering and use of some wild food species is common among farmers in the hill country east of Graz. However, most uses are known by few farmers only. The CUV facilitates the evaluation of the culinary importance of species and makes comparisons between regions and over time possible. The classification following gathering and use variables can be used to better understand how people classify the elements of their environment. The findings of this study add to discussions about food heritage, popularized by organizations like Slow Food, and bear significant potential for organic farmers. 相似文献62.
Understanding stopover decisions of long-distance migratory birds is crucial for conservation and management of these species along their migratory flyway. Recently, an increasing number of Barnacle geese breeding in the Russian Arctic have delayed their departure from their wintering site in the Netherlands by approximately one month and have reduced their staging duration at stopover sites in the Baltic accordingly. Consequently, this extended stay increases agricultural damage in the Netherlands. Using a dynamic state variable approach we explored three hypotheses about the underlying causes of these changes in migratory behavior, possibly related to changes in (i) onset of spring, (ii) potential intake rates and (iii) predation danger at wintering and stopover sites. Our simulations showed that the observed advance in onset of spring contradicts the observed delay of departure, whereas both increased predation danger and decreased intake rates in the Baltic can explain the delay. Decreased intake rates are expected as a result of increased competition for food in the growing Barnacle goose population. However, the effect of predation danger in the model was particularly strong, and we hypothesize that Barnacle geese avoid Baltic stopover sites as a response to the rapidly increasing number of avian predators in the area. Therefore, danger should be considered as an important factor influencing Barnacle goose migratory behavior, and receive more attention in empirical studies. 相似文献
63.
M F Wilkins L Boddy C W Morris R R Jonker 《Applied and environmental microbiology》1999,65(10):4404-4410
We describe here the application of a type of artificial neural network, the Gaussian radial basis function (RBF) network, in the identification of a large number of phytoplankton strains from their 11-dimensional flow cytometric characteristics measured by the European Optical Plankton Analyser instrument. The effect of network parameters on optimization is examined. Optimized RBF networks recognized 34 species of marine and freshwater phytoplankton with 91. 5% success overall. The relative importance of each measured parameter in discriminating these data and the behavior of RBF networks in response to data from "novel" species (species not present in the training data) were analyzed. 相似文献
64.
Johannes P. F. G. Helsper C. H. Ric de Vos Frank M. Maas Harry H. Jonker Hetty C. van den Broeck Wilco Jordi C. Sander Pot L. C. Paul Keizer Ad H. C. M. Schapendonk 《Physiologia plantarum》2003,117(2):171-178
The effect of supplemental UV-A (320–400 nm) radiation on tissue absorption at 355 nm, levels of various antioxidants (ascorbate, glutathione, carotenoids and flavonoids) and of antioxidant scavenging capacity were investigated with leaves and petals of Rosa hybrida , cv. Honesty and with leaves, petals and sepals of Fuchsia hybrida , cv. Dollarprinzessin. Supplemental UV-A did not result in visible changes in plant morphology of either species. In leaves it induced small increases in levels of chlorophylls a and b , the carotenoids antheraxanthin, lutein and β-carotene, and high increases in the flavonols quercetin and kaempferol. Petals hardly responded, while the coloured sepals of fuchsia showed an increase in quercetin derivatives. HPLC of unhydrolysed flavonoids showed that individual quercetin derivatives in leaves of both species and kaempferol derivatives in rose leaves increased 2-fold. Some kaempferol derivatives in fuchsia leaves were more than 2-fold enhanced or were newly induced by supplemental UV-A. Increases in l-ascorbic acid levels in fuchsia leaves, and decreases in rose leaves as result of supplemental UV-A were observed, but differences appeared statistically not significant, while l-ascorbate levels remained unchanged in the other tissues investigated. Anthocyanins and reduced glutathione levels were unaffected in all tissues. The combined UV-A induced increases in concentrations of these antioxidant species, did not lead to significant increases in antioxidant capacity of tissues, measured as Trolox equivalents in 50%-ethanol extracts. Light absorption at 355 nm of leaf extracts was significantly increased upon UV-A exposure. Our results indicate that the major protection towards UV-A exposure, in particular in the leaves, will originate from absorption of irradiation, and not from scavenging reactive oxygen species. 相似文献
65.
Bradley RD; Adkins RM; Honeycutt RL; McDonald JH 《Molecular biology and evolution》1998,15(6):709-717
Using the strictly neutral model as a null hypothesis, we tested for
deviations from expected levels of nucleotide polymorphism at the alcohol
dehydrogenase locus (Adh-1) within and among four species of pocket gophers
(Geomys bursarius major, G. knoxjonesi, G. texensis llanensis, and G.
attwateri). The complete protein-encoding region was examined, and 10
unique alleles, representing both electromorphic and cryptic alleles, were
used to test hypotheses (e.g., the neutral model) concerning the
maintenance of genetic variation. Nineteen variable sites were identified
among the 10 alleles examined, including 9 segregating sites occurring in
synonymous positions and 10 that were nonsynonymous. Several statistical
methods, including those that test for within-species variation as well as
those that examine variation within and among species, failed to reject the
null hypothesis that variation (both within and between species of Geomys)
at the Adh locus is consistent with the neutral theory. However, there was
significant heterogeneity in the ratio of polymorphism to divergence across
the gene, with polymorphisms clustered in the first half of the coding
region and fixed differences clustered in the second half of the gene. Two
alternative hypotheses are discussed as possible explanations for this
heterogeneity: an old balanced polymorphism in the first half of the gene
or a recent selective sweep in the second half of the gene.
相似文献
66.
Fructan: fructan fructosyl transferase (FFT), one of the enzymesinvolved in the synthesis of ß-2,1 linked fructosepolymers has been purified 205-fold from tubers of Helianthustuberosus harvested in the accumulation phase. The molecularweight of the native as well as the SDS-denatured protein isapproximately 70 kDa. On IEF, the protein was separated intofive molecular species with pl values between pH 4.55.0.The optimum pH for fructosyl transfer activity was between 5.57.0.Temperature optimum was in the range of 25-35° C; the Q10value between 25 and 5° C was 1.14. FTT catalysed the self-transferof fructosyl groups with GF2, GF3, GF4 or GF5 as substrate andacceptor. The rate of elf-transfer with both GF2 and GF3 increasedlinearly with substrate concentration up to 100 mol m3and was still not saturated at 600 and 300 mol m3, respectively.FFT was unable to hydrolyse GF or to catalyse the self-transferwith GF but could mediate the transfer of fructosyl units frominulin on to GF. Key words: Fructan: fructan fructosyl transferase, Helianthus tuberosus, Jerusalem artichoke, purification, kinetics 相似文献
67.
Evidence that biosynthesis of phosphatidylethanolamine, phosphatidylcholine, and triacylglycerol occurs on the cytoplasmic side of microsomal vesicles 总被引:13,自引:4,他引:9
Experiments were performed to localize the hepatic microsomal enzymes of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol biosynthesis to the cytoplasmic or lumenal surface of microsomal vesicles. Greater than 90 percent of the activities of fatty acid-CoA ligase (EC 6.2.1.3), sn-glycerol 3-phosphate acyltransferase (EC 2.3.1.15), lysophosphatidic acid acyltransferase, diacylglycerol acyltransferase (EC 2.3.1.20), diacylglycerol cholinephosphotransferase (EC 2.7.8.2), and diacylglycerol ethanolaminephosphotransferase (EC 2.7.8.1) was inactivated by proteolysis of intact microsomal vesicles. The phosphatidic acid phosphatase (EC 3.1.3.4) was not inactivated by any of the protease tested. Under conditions employed, <5 percent of the luminal mannose-6-phosphatase (EC 3.1.3.9) activity was lost. After microsomal integrity was disrupted with detergents, protease treatment resulted in a loss of >74 percent of the mannose-6-phosphatase activity. The latency of the mannose-6-phosphatase activity was not affected by protease treatment. Mannose-6-phosphatase latency was not decreased by the presence of the assay components of several of the lipid biosynthetic activities, indicating that those components did not disrupt the microsomal vesicles. None of the lipid biosynthetic activities appeared latent. The presence of a protease-sensitive component of these biosynthetic activities on the cytoplasmic surface of microsomal vesicles, and the absence of latency for any of these biosynthetic activities suggest that the biosynthesis of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol occurs asymmetrically on the cytoplasmic surface of the endoplasmic reticulum. The location of biosynthetic activities within the transverse plane of the endoplasmic reticulum is of particular interest for enzymes whose products may be either secreted or retained within the cell. Phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol account for the vast majority of hepatic glycerolipid biosynthesis. The phospholipids are utilized for hepatic membrane biogenesis and for the formation of lipoproteins, and the triacylglycerols are incorporated into lipoproteins or accumulate within the hepatocyte in certain disease states (14). The enzymes responsible for the biosynthesis of these glycerolipids (Scheme I) from fatty acids and glycerol-3P have all been localized to the microsomal subcellular fraction (12, 16, 29, 30). Microsomes are derived from the endoplasmic reticulum and are sealed vesicles which maintain proper sidedness. (11, 22). The external surface of these vesicles corresponds to the cytoplasmic surface of the endoplasmic reticulum. Macromolecules destined for secretion must pass into the lumen of the endoplasmic reticulum (5, 23). Uncharged molecules of up to approximately 600 daltons are able to enter the lumen of rat liver microsomes, but macromolecules and charged molecules of low molecular weight do not cross the vesicle membrane (10, 11). Because proteases neither cross the microsomal membrane nor destroy the permeability barrier of the microsomal vesicles, only the enzymes and proteins located on the cytoplasmic surface of microsomal vesicles are susceptible to proteolysis unless membrane integrity is disrupted (10, 11). By use of this approach, several enzymes and proteins have been localized in the transverse plane of microsomal membranes (11). With the possible exception of cytochrome P 450, all of the enzymes and proteins investigated were localized asymmetrically by the proteolysis technique (11). By studies of this type, as well as by product localization, glucose-6-phosphate (EC 3.1.3.9) has been localized to the luminal surface of microsomal vesicles (11) and of the endoplasmic reticulum (18, 19). All microsomal vesicles contain glucose-6-phosphatase (18, 19) which can effectively utilize mannose-6-P as a substrate, provided the permeability barrier of the vesicles has been disrupted to allow the substrate access to the active site located on the lumenal surface (4). An exact correspondence between mannose- 6-phosphate activity and membrane permeability to EDTA has been established (4). The latency of mannose-6-phosphatase activity provides a quantitative index of microsomal integrity (4.) Few of the microsomal enzymes in the synthesis of phosphatidylcholine, phosphatidylethanolamine, and triacylglycerol have been solubilized and/or purified, and little is known about the topography of these enzymes in the transverse or lateral planes of the endoplasmic reticulum. An asymmetric location of these biosynthetic enzymes on the cytoplasmic or lumenal surface of microsomal vesicles may provide a mechanism for regulation of the glycerolipids to be retained or secreted by the cell, and for the biogenesis of asymmetric phospholipid bilayers. In this paper, we report investigations on the localization of all seven microsomal enzymes (Scheme I) in the biosynthesis of triacylglycerol, phosphatidylcholine, and phosphatidylethanolamine, using the protease technique with mannose-6-phosphatase serving as luminal control activity. The latency of these lipid biosynthetic enzymes was also investigated, using the latency of mannose-6-phosphatase as an index of microsomal integrity. 相似文献
68.
69.
Tanya Marchant Ritgak Dimka Tilley-Gyado Tsegahun Tessema Kultar Singh Meenakshi Gautham Nasir Umar Della Berhanu Simon Cousens Joanna RM Armstrong Schellenberg 《PloS one》2015,10(5)
BackgroundFamilies in high mortality settings need regular contact with high quality services, but existing population-based measurements of contacts do not reflect quality. To address this, in 2012, we designed linked household and frontline worker surveys for Gombe State, Nigeria, Ethiopia, and Uttar Pradesh, India. Using reported frequency and content of contacts, we present a method for estimating the population level coverage of high quality contacts.ConclusionsMeasuring content of care to reflect the quality of contacts can reveal missed opportunities to deliver best possible health care. 相似文献
70.
Defective paracrine signalling by TGFbeta in yolk sac vasculature of endoglin mutant mice: a paradigm for hereditary haemorrhagic telangiectasia 总被引:3,自引:0,他引:3
Carvalho RL Jonker L Goumans MJ Larsson J Bouwman P Karlsson S Dijke PT Arthur HM Mummery CL 《Development (Cambridge, England)》2004,131(24):6237-6247
Hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant disorder in humans that is characterised by multisystemic vascular dyplasia and recurrent haemorrhage. Germline mutations in one of two different genes, endoglin or ALK1 can cause HHT. Both are members of the transforming growth factor (TGF) beta receptor family of proteins, and are expressed primarily on the surface of endothelial cells (ECs). Mice that lack endoglin or activin receptor like kinase (ALK) 1 die at mid-gestation as a result of defects in the yolk sac vasculature. Here, we have analyzed TGFbeta signalling in yolk sacs from endoglin knockout mice and from mice with endothelial-specific deletion of the TGFbeta type II receptor (TbetaRII) or ALK5. We show that TGFbeta/ALK5 signalling from endothelial cells to adjacent mesothelial cells is defective in these mice, as evidenced by reduced phosphorylation of Smad2. This results in the failure of vascular smooth muscle cells to differentiate and associate with endothelial cells so that blood vessels remain fragile and become dilated. Phosphorylation of Smad2 and differentiation of smooth muscle can be rescued by culture of the yolk sac with exogenous TGFbeta1. Our data show that disruption of TGFbeta signalling in vascular endothelial cells results in reduced availability of TGFbeta1 protein to promote recruitment and differentiation of smooth muscle cells, and provide a possible explanation for weak vessel walls associated with HHT. 相似文献