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41.
Keloids are skin fibroproliferative disorders, resulting from abnormal healing of deep cutaneous injuries. Cryosurgery, the most common treatment for keloids, causes skin traumas. Even though the clinical practice of cryosurgery has increased, effective wound healing therapy is still lacking. In this investigation, nonwoven nanofibrous patches composed of ulvan, a marine sulfated polysaccharide exhibiting anti-inflammatory and antioxidant activities, and polyethylene oxide (PEO) were fabricated through electrospinning and characterized. Their wound healing efficacy on skin traumas resulting from cryosurgical treatment of keloids was clinically tested and evaluated in comparison to a reference product. Twenty-four volunteer patients undergoing cryosurgery as a treatment of keloids were selected to apply either the ulvan/PEO patch or the reference product for 21 days. The ulvan/PEO patch, 21 days after cryosurgery, showed significant wound healing, elimination of skin inflammation, restoration of biophysical parameters similar to normal values and significant decrease in haemoglobin concentration, skin texture and volume, while no discomfort or adverse reaction was observed. In contrast, the reference product showed inferior performance in all evaluated parameters. The designed ulvan/PEO patch represents the first wound dressing to effectively heal skin trauma after cryosurgical treatment of keloids.  相似文献   
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The characteristics (natural, socioeconomic and administrative/institutional) of Alfeios River basin, in Greece, are identified and presented, incorporating and critically reviewing all possibly found literature. The Alfeios River is a water resources system of great natural, ecological, social and economic importance for Western Greece, since it has the longest and highest flow rate watercourse in the Peloponnisos region. Moreover, the river basin was exposed in the last decades to a plethora of environmental stresses (such as hydrogeological alterations, intensively irrigated agriculture, surface and groundwater overexploitation and infrastructure developments), resulting in the degradation of its quantitative and qualitative characteristics. It is therefore necessary for the development of an integrated river basin management plan for this basin, to study and analyse the interplay between the river components and the exerted environmental stresses, taking into account the puzzle of various and conflicting water uses, including water supply, irrigation, hydropower generation, lignite thermal power production and recreation. Mitigative, preventive and control measures for the analysed environmental stresses are epigrammatically depicted. Focusing on the problematic features, the present work provides a concrete foundation for the determination and conceptualisation of management objectives and possible sustainable alternatives.  相似文献   
44.
Limited information is available about the impact of grazing on soil and plant nutrient contents in Mediterranean deciduous oak forests grazed by both livestock and wild life. Thus, the main objective of this study was to investigate the effect of wild boar and small ruminants grazing in a coppice oak forest in N Greece. Eight even‐aged stands of similar canopy cover and site quality were selected: four stands with long‐time grazing mainly by wild boar and four stands with long‐time grazing by sheep and goats. A plot of 150 m2 in each of the stands was fenced in order to be protected from grazing. A similarly sized plot open to grazing was assigned next to the fenced plot. Species composition was recorded in fenced and grazed plots. Soil samples and individual plants of the dominant palatable grass species Dactylis glomerata and Brachypodium sylvaticum were collected in every fenced and grazed plot. These samples were analysed for contents of nutrients. The results indicated that grazing increased organic matter, C, and total N, P and Ca, while it had no effect on the plant nutrients Mg, Na, K and all micronutrients, and pH as well. Wild boar grazing had a significantly negative impact on the concentrations of Na, Fe, Zn, and Mn in the soil. Beside a decrease in K and Mn, grazing had minimal effects on the contents of plant nutrients. Conversely, wild boar grazing increased the contents of several nutrients such as N, Na, Cu and Fe in plant tissue. It seems that species composition was more affected by the topography and management than by the soil features as revealed by RDA analysis. The results of this study indicate that it is important to maintain moderate small ruminant grazing intensity for the sustainable multi‐disciplinary management of coppice oak forests. It is also important to control wild boar population in order to facilitate ecosystem process, soil preservation and forage quality.  相似文献   
45.
OBJECTIVE: To evaluate postsurgical outcome in dairy cows with left-displaced abomasum (LDA) with regard to severity of fatty liver and assess the usefulness of preoperative determination of serum ornithine carbamoyl transferase (OCT) activity, bile acids concentration, and other variables for evaluating liver function during the postsurgical convalescence period. DESIGN: Prospective study. ANIMALS: 68 Holstein cows. PROCEDURES: Blood and liver biopsy specimens were obtained during standing LDA surgery. Liver tissue was examined histologically and classified by severity of fatty change. Serum activities of liver-derived enzymes and concentrations of total lipids, triglycerides, bile acids, glucose, beta-hydroxybutyric acid, bilirubin, and nonesterified fatty acids were determined. RESULTS: Most cows with LDA and cows with severe fatty liver were detected within the first month after calving. Postsurgical outcome was related to severity of fatty liver. All cows that died had severe fatty liver. Serum activities of OCT, aspartate aminotransferase, and glutamate dehydrogenase and serum total bilirubin concentration were sensitive indicators of fatty liver. Serum bile acids concentration was not an accurate indicator of fatty liver. CONCLUSIONS AND CLINICAL RELEVANCE: Postsurgical outcome of cows undergoing surgery to correct LDA was related to fatty liver severity. Assessment of serum activities of OCT, aspartate aminotransferase, and glutamate dehydrogenase and serum total bilirubin concentration is recommended for diagnosis of fatty liver in dairy cows with LDA, whereas determination of bile acids concentration is not. The strong correlation between OCT activity and degree of hepatocellular damage supports use of this enzyme for assessing severity of fatty liver and predicting postsurgical outcome in cows with LDA.  相似文献   
46.
Red leaf lettuce (Lollo Rosso) was grown under three types of plastic films that varied in transparency to UV radiation (designated as UV block, UV low, and UV window). Flavonoid composition was determined by high-performance liquid chromatography (HPLC), total phenolics by the Folin-Ciocalteu assay, and antioxidant capacity by the oxygen radical absorbance capacity (ORAC) assay. Exposure to increased levels of UV radiation during cultivation caused the leaves to redden and increased concentrations of total phenols and the main flavonoids, quercetin and cyanidin glycosides, as well as luteolin conjugates and phenolic acids. The total phenol content increased from 1.6 mg of gallic acid equivalents (GAE)/g of fresh weight (FW) for lettuce grown under UV block film to 2.9 and 3.5 mg of GAE/g of FW for lettuce grown under the UV low and UV window films. The antioxidant activity was also higher in lettuce exposed to higher levels of UV radiation with ORAC values of 25.4 and 55.1 micromol of Trolox equivalents/g of FW for lettuce grown under the UV block and UV window films, respectively. The content of phenolic acids, quantified as caffeic acid, was also different, ranging from 6.2 to 11.1 micromol/g of FW for lettuce cultivated under the lowest and highest UV exposure plastic films, respectively. Higher concentrations of the flavonoid glycosides were observed with increased exposure to UV radiation, as demonstrated by the concentrations of aglycones after hydrolysis, which were cyanidin (ranging from 165 to 793 microg/g), quercetin (ranging from 196 to 880 microg/g), and luteolin (ranging from 19 to 152 microg/g). The results demonstrate the potential of the use of UV-transparent plastic as a means of increasing beneficial flavonoid content of red leaf lettuce when the crop is grown in polytunnels.  相似文献   
47.
Twenty-five compounds were identified from the dichloromethane and methanol extracts of royal jelly from Greece. Among them, 16 compounds are reported for the first time as royal jelly constituents, whereas 7 of them are isolated for the first time as natural products. The 7 new compounds were fatty acid derivatives: 10-acetoxydecanoic acid (1), trans-10-acetoxydec-2-enoic acid (2), 11-oxododecanoic acid (3), (11S)-hydroxydodecanoic acid (4), (10R,11R)-dihydroxydodecanoic acid (5), 3,11-dihydroxydodecanoic acid (6), and (11S),12-dihydroxydodecanoic acid (7). The structures of the isolated compounds were determined by spectroscopic methods, mainly by the concerted application of 1D and 2D NMR techniques (HMQC, HMBC) and mass spectrometry. The studied sample and the isolated compounds were tested for their antimicrobial activity against Gram-positive and Gram-negative bacteria and fungi and exhibited interesting activities.  相似文献   
48.
Possible associations between certain physical properties of cervical mucus (CM) and ovulation rate were studied in 21 superovulated Holstein cows. In CM samples collected at the beginning of estrus (0 h) and in 4 h intervals for the following 24 h, the pH, the spinnbarkeit (spinability), and the crystallization value were measured. Blood samples, collected at the same time points with CM samples, were assessed for progesterone and estradiol concentrations. At 48 h the number of ovulated follicles was counted by transrectal ultrasonography and the animals were allotted into 2 groups according to the occurrence of at least one (group A, n = 16) or no (group B, n = 5) ovulations. The pH was lower (P < 0.05) at 8 h (7.00 + 0.24) in group A compared with group B (7.55 + 0.12). In group A, spinnbarkeit was significantly lower at 0 h and 20 h, and higher at 8 h and 16 h compared with group B (0 h: 2.50 + 0.82 versus 6.95 + 0.41; 20 h: 3.00 + 1.89 versus 5.38 + 0.94; 8 h: 7.00 + 0.87 versus 2.75 + 0.43; 16 h: 7.00 + 1.41 versus 4.30 + 0.71, for groups A versus B, respectively). Crystallization was significantly lower at 4 h (2.00 + 0.63) and 20 h (1.50 + 0.82) in group A compared with group B (3.13 + 0.32 at 4 h and 3.00 + 0.41 at 20 h). Progesterone at all time points, and estradiol at 16 h, 20 h, and 24 h were lower (P < 0.05) in group A than in group B. The pH, crystallization, estradiol, and progesterone differed (P < 0.05) within one group, while sbk differed within both groups.Our results imply that during the periovulatory period, steadily low progesterone concentrations trigger alterations of certain CM characteristics, while extremely high estradiol concentration could prevent the occurrence of these alterations.  相似文献   
49.
Interest is increasing in establishing renewable sources for squalene, a functional lipid, as the conventional ones are limited. In the present study, squalene production was achieved in a wild-type laboratory Saccharomyces cerevisiae strain by two safe chemical means using terbinafine (0.05-0.55 mM) and methyl jasmonate (MJ) (0-1.00 mM). Bioprocess kinetics optimized by response surface methodology and monitored by high-performance liquid chromatography revealed a clear dependence of growth and squalene content (SQC) and yield (SQY) on the above regulators. Maximum SQC (10.02±0.53 mg/g dry biomass) and SQY (20.70±1.00 mg/L) were achieved using 0.442 mM terbinafine plus 0.044 mM MJ after 28 h and 0.300 mM terbinafine after 30 h, respectively. A 10-fold increase in SQY was achieved in comparison to that in the absence of regulator. The ruggedness of optimum conditions for SQY was verified for five industrial strains. The cellular lipid fraction (~12% of dry biomass) was rich in squalene (12-13%). Results are encouraging toward bioprocess scale up.  相似文献   
50.
The detailed phenolic composition (anthocyanins, flavonols, hydroxycinnamic acid derivatives, stilbenes, and flavan-3-ols) in the skin and flesh of the new BRS Clara and BRS Morena seedless table grapes has been studied using HPLC-DAD-ESI-MS/MS. The two grapes, especially BRS Morena, contained high amounts of phenolic compounds, mainly located in their skins and qualitatively not different from those found in Vitis vinifera grapes. In addition, BRS Morena (a teinturier variety) showed qualitatively different phenolic compositions in its skin and flesh, mainly affecting the anthocyanin and flavonol profiles. Consistent with high phenolic contents, high antioxidant capacity values were registered for both grape varieties, especially for BRS Morena. Proanthocyanidins and hydroxycinnamoyl-tartaric acids were the major phenolic compounds found in BRS Clara and were also important in BRS Morena, although anthocyanins were the main phenolic compounds in the latter case. These results suggest that the entire grapes, including the skin, may potentially possess properties that are beneficial to human health. In this context, the BRS Morena grape can be considered as a high resveratrol producer.  相似文献   
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