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71.
Flávio B Barros Susana AM Varela Henrique M Pereira Luís Vicente 《Journal of ethnobiology and ethnomedicine》2012,8(1):1-20
Background
Zootherapy inventories are important as they contribute to the world documentation of the prevalence, importance and diversity of the medicinal use of animals in traditional human communities. The present study aims to contribute with a more valuable example of the zootherapy practices of a traditional community in the Brazilian Amazonia ?C the ??Riozinho do Anfrísio?? Extractive Reserve, in Northern Brazil.Methods
We used the methods of participant observation and semi-structured interviews, applied to 25 informants. We employed the combined properties of two indices to measure the medicinal importance of each cited species to the studied community, as well as their versatility in the treatment of diseases: the well known Use Value (UV) and the Medicinal Applications Value (MAV) that we developed.Results
We recorded 31 species of medicinal animals from six taxonomic categories, seven of which are new to science. The species are used for the treatment of 28 diseases and one species is used as an amulet against snakebites. The five species with the highest UV indices are the most popular and valued by the studied community. Their contrasting MAV indices indicate that they have different therapeutic properties: specific (used for the treatment of few diseases; low versatility) and all-purpose (several diseases; high versatility). Similarly, the most cited diseases were also those that could be treated with a larger number of animal species. Ten species are listed in the CITES appendices and 21 are present in the IUCN Red List. The knowledge about the medicinal use of the local fauna is distributed evenly among the different age groups of the informants.Conclusions
This study shows that the local fauna represents an important medicinal resource for the inhabitants of the protected area. The combined use of the UV and MAV indices allowed identifying the species with the highest therapeutic potential. This type of information about a species may be of interest to pharmacological research, and is crucial to its conservation, since it helps signaling the species that may undergo higher hunting pressures. Data on zootherapy can also be of interesting to ecologists by contributing to indicators of local biodiversity richness. 相似文献72.
Various methods of suberin extraction have been used in order to identify monomers of this complex polymer. Pre-extraction of waxes has allowed us to identify for the first time 3-friedelanol as a terpen from cork. Moreover, the wax chemical composition found here varied from previous results since cerin was not identified while friedelin and betulin were. Three fractions were obtained: a polymeric, a monomeric and a low molecular weight fraction, the last of which has never before been described. 2,6-heptanediol was found to be the main compound of this fraction. Furthermore, depolymerisation at room temperature gives the same yields as those obtained at reflux, defining an easier and cheaper methodology. 相似文献
73.
Seventy-three patients were studied after ingesting a liquid glucose meal, tagged with 113Indium. Nineteen of these patients were awaiting surgery for their duodenal ulcer, while 54 were studied postoperatively, 25 of whom experienced troublesome postprandial (dumping) symptoms in their daily lives. The radioactive marker emptied significantly faster in the symptomatic patients than in the symptomfree, pre and post-operative groups (initial emptying rate 3.45 ± 0.23, compared with 1.16 ± 0.19 and 1.27 ± 0.15% fall in counts/min respectively; p < 0.01). Initial (20 min) rises in the plasma concentrations of neurotensin-like immunoreactivity measured during the test correlated significantly with the rate of gastric emptying in all patients, being greatest in patients with dumping symptoms. Physiological concentrations of neurotensin have been shown to delay gastric emptying. The excessive rise in plasma neurotensin-like immunoreactivity in patients with dumping symptoms, presumably occuring as a result of the rapid passage of nutrients to the neurotensin-rich ileum, may possibly have a compensatory role in slowing further emptying from the stomach. 相似文献
74.
Soil microbial activities in a reed-bed used for effluent purification of a small cheese-dairy farm under a Mediterranean climate were described and studied. This work aims to demonstrate (i) whether certain enzyme activities used as bioindicators of dairy waste degradation (beta-galactosidase and protease) vary over time, which might influence organic matter degradation and (ii) whether specific microbial communities are selected through contact with the discarded effluent using community level catabolic profiles (CLCPs). beta-galactosidase and protease activities were followed in a 14-month monitoring experiment. These enzyme activities were strongly expressed during the whey-discarding period from February to May. CLCPs using Biolog Ecoplate showed great microbial diversity, as described by Shannon-Weaver index, and no difference was observed in microbial diversity between areas at the receiving end of the reed-bed (where effluent was discarded) and those at the opposite end. This may be explained by successive environmental factors which made enzyme activities vary: whey discarded from February to May and Mediterranean climate conditions (drying-rewetting effects on summer). Microbial enumeration using epifluorescence microscopy also showed a pattern linked to Mediterranean conditions with a drastic decrease in biomass during summer drought. These results on functional biodiversity were correlated with high purification yields: the minimum decrease in Biological Demand in Oxygen was 84% and that in suspended solids was 75%. 相似文献
75.
Marsupials and monotremes sort genome treasures from junk 总被引:1,自引:0,他引:1
A recent landmark paper demonstrates the unique contribution of marsupials and monotremes to comparative genome analysis, filling an evolutionary gap between the eutherian mammals (including humans) and more distant vertebrate species. 相似文献
76.
77.
Catimel B; Scott AM; Lee FT; Hanai N; Ritter G; Welt S; Old LJ; Burgess AW; Nice EC 《Glycobiology》1998,8(9):927-938
We describe a novel immobilization technique to investigate interactions
between immobilized gangliosides (GD3, GM1, and GM2) and their respective
antibodies, antibody fragments, or binding partners using an optical
biosensor. Immobilization was performed by direct injection onto a
carboxymethyldextran sensor chip and did not require derivatization of the
sensor surface or the ganglioside. The ganglioside appeared to bind to the
sensor surface by hydrophobic interaction, leaving the carbohydrate epitope
available for antibody or, in the case of GM1, cholera toxin binding. The
carboxyl group of the dextran chains on the sensor surface did not appear
to be involved in the immobilization as evidenced by equivalent levels of
immobilization following conversion of the carboxyl groups into acyl amino
esters, but rather the dextran layer provided a hydrophilic coverage of the
sensor chip which was essential to prevent nonspecific binding. This
technique gave better reactivity and specificity for anti- ganglioside
monoclonal antibodies (anti-GD3: KM871, KM641, R24; and anti-GM2: KM966)
than immobilization by hydrophobic interaction onto a gold sensor surface
or photoactivated cross-linking onto carboxymethydextran. This rapid
immobilization procedure has facilitated detailed kinetic analysis of
ganglioside/antibody interactions, with the surface remaining viable for a
large number of cycles (>125). Kinetic constants were determined from
the biosensor data using linear regression, nonlinear least squares and
equilibrium analysis. The values of kd, ka, and KAobtained by nonlinear
analysis (KAKM871 = 1.05, KM641 = 1.66, R24 = 0.14, and KM966 = 0.65 x
10(7) M- 1) were essentially independent of concentration and showed good
agreement with data obtained by other analytical methods.
相似文献
78.
Assessing population density is crucial for studying the ecology and evolutionary biology of species as well as for conservation purposes. Here we used point count methods to infer population density in a single-island endemic passerine bird, the Réunion Grey White-eye Zosterops borbonicus, that displays striking evidence of differentiation at a small spatial scale. Population density was estimated at 5.17 birds ha?1 (CL 4.85–5.50), a value somewhat higher than previously believed. This estimation provides the first detailed estimation of bird population density in the vulnerable summit ecosystems of Réunion and will possibly allow a better understanding of the evolutionary causes of this plumage colour variation. 相似文献
79.
Two isozymes of laccase were obtained from an induced liquid culture of Marasmius quercophilus with p-hydroxybenzoic acid as the inducer. Both the constitutive and the induced isozyme have a molecular mass of 60 kDa as determined by polyacrylamide gel electrophoresis. Using isoelectric focusing, we found three isozymes with the constitutive enzyme (pI 4, 4.2, 4.4) and four of the induced form (pI 4.75, 4.85, 4.95, 5.1). We observed certain differences between these two isozymes; the specific activity of the induced isozyme was twice as high, and two optimum pH levels (5 and 6) were observed with the induced isozyme (only one, pH 5, for the constitutive isozyme). However, both of these enzymes have the same thermal stability and the same temperature for their highest activity (80 degrees C). Furthermore, the reactivity of both these enzymes with aromatic compounds was similar. The use of mediators extended the oxidized substrate range of the laccases studied. Various products of degradation were observed, depending on the mediator used. When laccase was used alone, the decrease of the signal corresponding to the aromatic cycle, without any formations of other peaks at different wavelengths, suggested polymerisation of aromatic compounds. 相似文献
80.
Influence of a natural and a synthetic inhibitor of factor XIIIa on fibrin clot rheology 总被引:2,自引:0,他引:2 下载免费PDF全文
We investigated the origins of greater clot rigidity associated with FXIIIa-dependent cross-linking. Fibrin clots were examined in which cross-linking was controlled through the use of two inhibitors: a highly specific active-center-directed synthetic inhibitor of FXIIIa, 1,3-dimethyl-4,5-diphenyl-2[2(oxopropyl)thio]imidazolium trifluoromethylsulfonate, and a patient-derived immunoglobulin directed mainly against the thrombin-activated catalytic A subunits of thrombin-activated FXIII. Cross-linked fibrin chains were identified and quantified by one- and two-dimensional gel electrophoresis and immunostaining with antibodies specific for the alpha- and gamma-chains of fibrin. Gamma-dimers, gamma-multimers, alpha(n)-polymers, and alpha(p)gamma(q)-hybrids were detected. The synthetic inhibitor was highly effective in preventing the production of all cross-linked species. In contrast, the autoimmune antibody of the patient caused primarily an inhibition of alpha-chain cross-linking. Clot rigidities (storage moduli, G') were measured with a cone and plate rheometer and correlated with the distributions of the various cross-linked species found in the clots. Our findings indicate that the FXIIIa-induced dimeric cross-linking of gamma-chains by itself is not sufficient to stiffen the fibrin networks. Instead, the augmentation of clot rigidity was more strongly correlated with the formation of gamma-multimers, alpha(n)-polymers, and alpha(p)gamma(q)-hybrid cross-links. A mechanism is proposed to explain how these cross-linked species may enhance clot rigidity. 相似文献