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21.
Microparticles continue to receive widespread attention from food professionals because of their potential use as carriers of bioactive substances. This study demonstrates a novel method to prepare casein microparticles, which co-assemble with α-tocopherol (αT) into emulsion droplets. When the particles were extracted from the pectin matrix via enzymatic degradation, they remained stable in a buffer solution for at least 3 weeks. Optical microscopy showed that the size distribution of the microparticles is between 5 μm and 50 μm, which is in accordance with previous observations in blend films. High-performance liquid chromatography revealed that the amounts of αS1- and κ-casein in the microparticles are significantly higher than those in native casein micelles. Confocal Raman microscopy showed that in the presence of α-tocopherol, the microparticles assemble into emulsion droplets, with phenol in the core and casein in the shell. Herein, we demonstrate a new method to form casein-based emulsion droplets for potential use as carriers of bioactive substances.  相似文献   
22.
The incidence of mycobacterial infections was monitored in brown bears (Ursus arctos) in the National Park Low Tatras in the central European Carpathians in Slovakia. Tissue samples of 20 brown bears were examined microscopically and by culture for the presence of mycobacteria. Acid-fast rods were detected by Ziehl-Neelsen staining in a smear from the kidney of one brown bear, although the culture was negative for mycobacteria. Mycobacterium avium subsp. paratuberculosis, the causative agent of paratuberculosis in ruminants, was isolated from the intestinal mucosa of another two brown bears. The isolates were identified by polymerase chain reaction for the specific insertion sequence IS900. Using standardized IS900 restriction fragment length polymorphism (RFLP) analysis, the M. a. paratuberculosis isolates were classified as RFLP type B-C1, which also were detected in the infected cattle in surrounding area. This study describes the first isolation of M. a. paratuberculosis from a brown bear. Our results confirm that animal species other than ruminants can become infected with M. a. paratuberculosis and can act as potential vectors and/or reservoirs of the infection.  相似文献   
23.
Glacial relicts have been regionally more common in glacial than in recent times. A rigorous assessment of which species are indeed glacial relicts is extremely difficult because direct evidence is untraceable or equivocal for many species. We aimed to identify species of the Western Carpathian flora (vascular plants, bryophytes and terrestrial lichens) that display apparent biogeographical and ecological symptoms, suggesting a wider regional or supra-regional distribution during glacial times, or at least before the middle-Holocene climate optimum. We worked with the premise that exemplary relict species should tolerate continental and/or arctic climates, should have large distribution ranges with disjunctions, being regionally rare and ecologically conservative nowadays, should be associated with habitats that occurred during glacial times (tundra, steppe, peatland, open coniferous forest) and should display a restriction of ecological niches in the study region. The assessed species were primarily those with boreo-continental or artcic-alpine distribution. We demonstrated a conspicuous gradient of glacial-relict symptoms, with Carex vaginata, Betula nana, Trichophorum pumilum, Nephroma arcticum, Saxifraga hirculus and Cladonia stellaris topping the ranking. Based on the arbitrary ranking, 289 taxa can be considered high-probability relicts. For only a minority of them, there are any phylogeographical and/or palaeoecological data available from the study area. Biogeographical and ecological symptoms of 144 taxa suggest that they retreated rapidly after the Last Glacial Maximum whereas other species probably retreated later. The first principal component of biogeographical symptoms sorted species from circumpolar arctic-alpine species of acidic peatlands and wet tundra to strongly continental species of steppe, steppe-tundra and mineral-rich fens. This differentiation may mirror the altitudinal zonation of glacial vegetation in the Western Carpathians.  相似文献   
24.
Species of the genus Karwinskia are medicinal woody plants producing secondary metabolites (anthracenones, peroxisomicine A1) with antitumour effects. We investigated the photosynthetic and growth characteristics of Karwinskia parvifolia Zucc. and Karwinskia humboldtiana Rose plants grown at two rates of nitrogen supply. There were significant differences in growth, CO2 exchange (photosynthesis, respiration), chlorophyll and nitrogen concentration between plants grown at high nitrogen supply (HN) and low nitrogen supply (LN). At HN, the plants of both species grew faster than those cultivated at LN. Rates of photosynthesis, leaf respiration and root respiration, quantum yield, the concentration of chlorophylls ( a, b, a + b ), specific leaf area, leaf mass ratio and peroxisomicine A1 concentration were higher in plants grown at HN. The species-specific difference in the daily carbon budget was mainly due to variation in rates of carbon fixation. K. parvifolia responded more strongly to the nitrogen treatment than K. humboldtiana , in terms of growth, as well as with respect to photosynthesis and peroxisomicine A1 concentration.  相似文献   
25.
The propensity of a recombinant protein produced in bacteria to aggregate has been assumed to be unpredictable, and inclusion bodies have been thought of as wasted cell material. However, a target protein can be purposely driven to inclusion bodies, which demonstrate full cell tolerable activity. Sialic acid aldolase, N-terminally fused with the cellulose-binding module of Clostridium cellulovorans, was almost quantitatively physiologically aggregated into active inclusion bodies. These inclusion bodies were entrapped in alginate beads and crosslinked by glutaraldehyde. The immobilized biocatalyst generated by this crosslinked inclusion bodies (CLIB) technology was used in a repetitive batch protocol for sialic acid production that was monitored on-line by flow calorimetry. The required substrate, N-acetyl-D-mannosamine, was obtained by partially improved alkaline epimerization.  相似文献   
26.
Methane production by intestinal methanogenic Archaea and their community structure were compared among phylogenetic lineages of millipedes. Tropical and temperate millipedes of 35 species and 17 families were investigated. Species that emitted methane were mostly in the juliform orders Julida, Spirobolida, and Spirostreptida. The irregular phylogenetic distribution of methane production correlated with the presence of the methanogen-specific mcrA gene. The study brings the first detailed survey of methanogens’ diversity in the digestive tract of millipedes. Sequences related to Methanosarcinales, Methanobacteriales, Methanomicrobiales and some unclassified Archaea were detected using molecular profiling (DGGE). The differences in substrate preferences of the main lineages of methanogenic Archaea found in different millipede orders indicate that the composition of methanogen communities may reflect the differences in available substrates for methanogenesis or the presence of symbiotic protozoa in the digestive tract. We conclude that differences in methane production in the millipede gut reflect differences in the activity and proliferation of intestinal methanogens rather than an absolute inability of some millipede taxa to host methanogens. This inference was supported by the general presence of methanogenic activity in millipede faecal pellets and the presence of the 16S rRNA gene of methanogens in all tested taxa in the two main groups of millipedes, the Helminthophora and the Pentazonia.  相似文献   
27.
The interrelationship of dietary calcium (Ca) intake, alcohol consumption, blood lead (BPb), blood cadmium (BCd), age, and body mass index (BMI) to blood pressure was examined in 267 peasant women 40-85 years of age. They were residents of two rural areas in Croatia and differed with regard to dietary Ca intake: 100 women with low Ca intake (approximately 450 mg/day) and 167 women with relatively high Ca intake (approximately 940 mg/day). All of the women were nonsmokers and consumed very little or no alcohol. Median and range BPb values were 74 (29-251) microg/L in women with low Ca intake and 59 (21-263) microg/L in women with high Ca intake (p < 0.0002), whereas corresponding BCd values were 0.6 (0.2-3.6) microg/L and 0.6 (0.3-4.5) microg/L (p > 0.10). Results of multiple regression showed a significant (p < 0.05) increase in systolic blood pressure with age, BMI, and BCd, and marginally with alcohol consumption (multiple r = 0.48, p < 10(- 6)). An increase in diastolic blood pressure was significantly (p < 0.05) associated with BMI, age, and residence area (i.e., it was higher in women with low Ca intake), and marginally with BCd, and alcohol consumption (multiple r = 0.38, p < 10(-6)) When the two groups of women with different Ca intake were subdivided into consumers and nonconsumers of alcohol, BPb was related positively to alcohol consumption and inversely to Ca intake. The highest BPb was found in the subgroup of alcohol consumers with low Ca intake, and the lowest BPb in the subgroup of nonconsumers with high Ca intake: 78 (42-251) microg/L and 51 (22-192) microg/L, respectively (p < 10(-8)). Diastolic blood pressure was significantly higher in the former subgroup as compared to the latter: 95 (72-130) mm Hg and 90 (60-120) mm Hg, respectively (p < 0.05). This cannot be explained by age, BMI, or BCd, which were comparable in the two subgroups. The results indicate that alcohol consumption and low Ca intake can increase BPb, which may significantly contribute to an increase in diastolic blood pressure in female nonsmokers even at relatively low-level Pb exposure.  相似文献   
28.
In six sites in the Ko?ice Basin we collected 17,520 larvae of 15 mosquito species during the seasons (April–August) of 2010 and 2011. They were: Aedes vexans (Meigen, 1830), Ae. cinereus (Meigen, 1818) [or Ae. rossicus (Dolbeskin, Gorickaja & Mitrofanova, 1930], Ochlerotatus geniculatus (Olivier, 1791), Oc. refiki (Medschid, 1928), Oc. rusticus (Rossi, 1790), Oc. sticticus (Meigen, 1838), Oc. punctor (Kirby, 1837), Oc. cataphylla (Dyar, 1916), Oc. cantans (Meigen, 1818)[or Oc. annulipes (Meigen, 1830)], Oc. communis (De Geer, 1776), Oc. flavescens (Müller, 1764), Oc. leucomelas (Meigen, 1804), Culiseta annulata (Schrank, 1776), Culex pipiens (L., 1758) [or Cx. torrentium (Martini, 1925)] and Anopheles maculipennis s.l. The objective of the present research was to identify the mosquito larvae species diversity and compare their distribution and density in urban and suburban localities of the monitored territory.  相似文献   
29.
30.
The morphologies of 15 rare chlorococcalean algae, i.e. three species of the Characiaceae [Hydrianum crassiapex Korshikov, H. viride (Scherffel) H. Ettl, Characiellopsis skujae (Fott) Komárek], four taxa of the genus Pediastrum Meyen [Pediastrum privum (Printz) E. Hegewald, P. duplex Meyen var. rugulosum Raciborski, P. angulosum (Ehrenberg) ex Meneghini, Pediastrum biradiatum Meyen], a radiococcalean alga Phacomyxa sphagnicola Skuja, Pseudodictyosphaerium fluviatile (Hindák) Hindák from the Dictyosphaeriaceae, three representatives of the family Oocystaceae (Amphikrikos minutissimus Korshikov, Gloeotaenium loitlesbergianum Hansgirg, Chlorolobion obtusum Korshikov) and three species of the genus Scenedesmus Meyen (S. ginzbergeri Kammerer, S. incrassatulus Bohlin, S. parisiensis Deflandre), are documented by drawings and micrographs and their taxonomy is discussed. Of these, Hydrianum viride, Pediastrum duplex var. rugulosum, Scenedesmus ginzbergeri and S. parisiensis are recorded for the first time in Slovakia. Presented at the International Symposium Biology and Taxonomy of Green Algae V, Smolenice, June 26–29, 2007, Slovakia.  相似文献   
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