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41.
Collagen has become a key-molecule in cell culture studies and in the tissue engineering field. Industrially, the principal sources of collagen are calf skin and bones which, however, could be associated to risks of serious disease transmission. In fact, collagen derived from alternative and riskless sources is required, and marine organisms are among the safest and recently exploited ones. Sea urchins possess a circular area of soft tissue surrounding the mouth, the peristomial membrane (PM), mainly composed by mammalian-like collagen. The PM of the edible sea urchin Paracentrotus lividus therefore represents a potential unexploited collagen source, easily obtainable as a food industry waste product. Our results demonstrate that it is possible to extract native collagen fibrils from the PM and produce suitable substrates for in vitro system. The obtained matrices appear as a homogeneous fibrillar network (mean fibril diameter 30–400 nm and mesh < 2 μm) and display remarkable mechanical properties in term of stiffness (146 ± 48 MPa) and viscosity (60.98 ± 52.07 GPa·s). In vitro tests with horse pbMSC show a good biocompatibility in terms of overall cell growth. The obtained results indicate that the sea urchin P. lividus can be a valuable low-cost collagen source for mechanically resistant biomedical devices.  相似文献   
42.
43.
Furosine: a suitable marker for assessing the freshness of royal jelly   总被引:7,自引:0,他引:7  
Fifteen commercial samples of royal jelly, consisting of 10 imported samples, and 5 samples of known origin obtained freshly harvested from beekeepers, were analyzed for protein, lysine, and furosine content. In addition, a commercial sample of royal jelly, at the beginning of its commercial shelf life, was stored for 10 months both at 4 degrees C and at room temperature in order to assess the development of the Maillard reaction (furosine) and relative nutritional damage (blocked lysine). The commercial royal jelly products contained different amounts of furosine, ranging from 37.1 to 113.3 mg/100 g protein, evidence of different storage times and conditions. The average furosine content of the royal jelly samples of known origin and harvesting was significantly lower than that of the imported samples (41.7 versus 73.6 mg/100 g protein, respectively). With regard to shelf life, furosine content increased significantly from 72.0 mg/100 g protein to 500.8 mg/100 g protein after 10 months of storage at room temperature, while it increased to a much lower level (100.5 mg/100 g protein) when the royal jelly was stored at 4 degrees C. However, nutritional damage, expressed as blocked lysine (calculated indirectly from the furosine content), was minor or negligible, 11.9 and 2.3% of total lysine, in samples stored at room temperature and at 4 degrees C, respectively. Lysine was determined by an innovative procedure based on high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The results showed that furosine is a suitable index for assessing the quality and freshness of royal jelly.  相似文献   
44.
Adsorption of cyanidin-3-glucoside in aqueous batch solutions was studied at pH 3.5 and 20 degrees C using 13 commercial resins with different hydrophobicity, surface areas (SA, 330-1200 m2/g), and pore radii (PR, 20-260 A). The solute affinity toward different resins was described in terms of Langmuir and Freundlich parameters; experimental data were well-fitted to the two isotherms, which were both utilized to compare resins adsorption capacity. The styrene-divinylbenzene EXA-118 resin (SA, 1200 m2/g; PR, 90 A) showed the maximum effectiveness among the tested resins; a good efficacy for removing cyanidin 3-glucoside was shown also by EXA-90 (SA, 630 m2/g; PR, 105 A). Some experiments on a styrene-divinylbenzene resin and an acrylic one demonstrated that adsorption was not influenced by pH variations of the solution within the range of 1.0-4.5. For the 10 resins having PR < or = 105 A, correlation analysis evidenced the linear increasing dependence of Freundlich constant KF on physical characteristics of surface area and pore radius. The adsorption of cyanidin 3-glucoside at 20 degrees C was compared with that of hesperidin performed in batch runs on the same resins. Moreover, the best resin (EXA-118) was tested with a sample of pigmented orange juice to assess its performance in terms of selectivity, adsorption, and desorption capabilities on a real matrix.  相似文献   
45.
Dermal microfilariae found in a dog from Sicily, Italy, were characterized morphologically and genetically and differentiated from those of all the other blood microfilariae commonly found in dogs. In particular, the microfilariae were short (mean length of 186.7 μm), presented a body flattened dorso-ventrally and a rounded head, bearing a tiny cephalic hook. The genetic identity of microfilariae herein studied was also assessed by molecular amplification, sequencing and analyzing of multiple ribosomal ITS-2 and mitochondrial (cox1 and 12S) target genes. Both morphologic and genetic characterization as well as the molecular phylogenetic history inferred using sequences of a barcoding dataset were concordant in supporting the identification of Cercopithifilaria at the genus level. Surprisingly, microfilariae here examined were well distinct from Cercopithifilaria grassii (Noè, 1907), from northern Italy, and resembled those of a species described in Brazil, Cercopithifilaria bainae Almeida & Vicente, 1984. This paper provides evidence for the existence of a Cercopithifilaria species infesting a dog from Sicily and also presents a PCR protocol on skin samples as a tool for further epidemiological studies, which could provide evidence on the aetiology and the natural history of this filarial species.  相似文献   
46.
In this study, pathological changes caused by Anoplocephala perfoliata in the ileocecal junction were investigated in 31 regularly slaughtered mixed-breed horses of both sexes. Our results showed a significant relationship between parasite burden and grading of histopathological lesions in the mucosa and submucosa. Hypertrophy of the circular muscle layer was found in infected horses. Moreover, enteric nervous system evaluation showed a significant injury of intestinal nervous elements in the horses with moderate to high parasitism expressed as an increase of degenerative-regressive changes in neuronal cells and a decrease in the number of myenteric ganglia and neuronal cells. These findings can help to clarify the pathogenesis of intestinal motility disorders associated with A. perfoliata infection in horses.  相似文献   
47.
Barley byproducts obtained by air classification have been used to produce a different barley functional spaghetti, which were compared to different commercial whole semolina samples. Total, insoluble, and soluble fiber and β-glucan contents of the barley spaghetti were found to be greater than those of commercial samples. Furthermore, it was proved that barley spaghetti reached the FDA requirements, which could allow these pastas to deserve the health claims "good source of dietary fiber" and "may reduce the risk of heart disease". When the barley coarse fraction was used, a flavan-3-ols enrichment and an increase of antioxidant activity were reported, while commercial samples showed the absence of flavan-3-ols and a higher presence of phenolic acids and tannins. Whole semolina commercial spaghetti had a significantly higher content of phenolic acids than semolina spaghetti samples. Besides, it was observed that when vital gluten was added to the spaghetti formulation, phenolic compounds were blocked in the gluten network and were partially released during the cooking process.  相似文献   
48.
Specific dietary requirements, e.g. celiac disease, as well as increased consumer demand for products of high nutritional value, makes the production of pasta from alternative cereals interesting. Raw material characterisation showed that the utilisation of oat and teff flour is beneficial as these ingredients contain higher levels of fibre and mineral composition is superior to that of wheat. Starch properties significantly influence pasta quality and therefore damaged starch levels, amylase activity, pasting properties and gelatinisation temperatures of the flours were investigated. Fresh egg pasta based on wheat, oat and teff flour was produced. Sensory properties of oat spaghetti were found to be very close to that of wheat pasta but improvement of smoothness and aroma is necessary, while teff spaghetti showed reduced sensory quality. An in vitro enzymatic digestion was performed using a dialysis system to mimic the behaviour of pasta as eaten and make predictions on the glycemic index (GI). The predicted GI was highest for wheat pasta, followed by teff and oat. Ultra structure was studied using confocal laser scanning microscopy, allowing the visualisation of differences in starch granule size and shape as well as gelatinisation occurring during the cooking process.  相似文献   
49.
Germination can be used to improve the sensory and nutritional properties of cereal and pseudocereal grains. Oat and quinoa are rich in minerals, vitamins and fibre while quinoa also contains high amounts of protein of a high nutritional value. In this study, oat and quinoa malts were produced and incorporated in a rice and potato based gluten free formulation. Germination of oat led to a drastic increase of α-amylase activity from 0.3 to 48 U/g, and minor increases in proteolytic and lipolytic activities. Little change was observed in quinoa except a decrease in proteolytic activity from 9.6 to 6.9 U/g. Oat malt addition decreased batter viscosities at both proofing temperature and during heating. These changes led to a decrease in bread density from 0.59 to 0.5 g/ml and the formation of a more open crumb, but overdosing of oat malt deteriorated the product as a result of excessive amylolysis during baking. Quinoa malt had no significant effect on the baking properties due to low α-amylase activity. Despite showing a very different impact on the bread quality, both malts influenced the electrophoretic patterns of rice flour protein similarly. This suggests that malt induced proteolysis does not influence the technological properties of a complex gluten free formulation.  相似文献   
50.
  • ? Understanding tree mortality processes across time requires long term studies. Spatiotemporal patterns of mortality in a 200 years-old mono-layered Norway spruce stand were evaluated to determine what factors affected individual-tree mortality.
  • ? We performed an analysis on two surveys (1993 and 2005) in a 1-ha permanent plot in the Paneveggio forest (Eastern Italian Alps). Tree diameter and age distribution between surveys were compared. We examined spatial patterns of living and dead trees before 1993, in 1993 and in 2005 using univariate and bivariate Ripley’s K(d) function, and a kernel estimator of local crowding. A logistic model was used to assess the effects of diameter, age, recent growth and competitive pressure on tree mortality.
  • ? Spatial pattern analysis indicated mortality was associated to tree neighbourhood (neighbour effect at 2–5 m). An increment of regularization of tree spatial pattern occurred due to density-dependent mortality. Logistic regression showed tree diameter and recent growth were determinant on mortality risk during the monitoring period.
  • ? Even if the stand is relatively aged, mortality dynamics are those typical of stem exclusion stage. Mortality was related to competitive dynamics, and small suppressed trees with slow growth rate had higher probability to die.
  •   相似文献   
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