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排序方式: 共有416条查询结果,搜索用时 293 毫秒
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62.
Jorgelia Castro Caio Magnotti Morgana Angelo Fabio Sterzelecki Fabiola Pedrotti Maria Fernanda Oliveira Thiago Soligo Dbora Fracalossi Vinicius Ronzani Cerqueira 《Aquaculture Research》2019,50(11):3267-3274
The feed provided to breeding fish is one of the main factors influencing the quality of fish gametes. This study was carried out to evaluate the influence of ascorbic acid on growth, haematological parameters and sperm quality of Lebranche mullet males (Mugil liza). Six diets with different levels of ascorbic acid (0; 53; 107; 216; 482 and 708 mg/kg) were tested in triplicate for 75 days. During spermiation (first gonadal maturation), 144 individuals (205.7 ± 11.5 g and 25.7 ± 0.4 cm) were randomly distributed in 18 experimental tanks. Growth parameters were evaluated at the beginning and end of the experiment. Fish blood was collected to analyse glucose, total protein and erythrocyte count (EC) (n = 9). Fish (n = 12) from each treatment were euthanized to determine hepatosomatic index (HSI) and gonadosomatic index (GSI). Semen was collected to evaluate spermatic density, cell membrane integrity and sperm motility. No difference (p > .05) was found on growth parameters, GSI, HSI and total protein. However, EC was lower in fish fed without ascorbic acid (the control group). Ascorbic acid supplementation provided positive effects on sperm characteristics. Fish from treatments with 53 and 107 mg/kg presented the best results for motility time (133.30 ± 4.25 and 135.00 ± 2.77 respectively). Treatments with 107, 216 and 708 mg/kg provided the best results for motility rate (92.0 ± 2.9%, 93.0 ± 5.8% and 93.0 ± 5.8% respectively). Supplementation with 107 and 216 mg/kg provided the best results for plasma membrane integrity (70.12 ± 9.10% and 76.3 ± 3.1% respectively). Lower spermatic density was observed in fish without ascorbic acid supplementation, although no difference was found in sperm density among the treatments with ascorbic acid (p < .05). Considering these results, supplementation of dietary ascorbic acid between 107 and 216 mg/kg optimizes the spermatic quality in males of lebranche mullet. 相似文献
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65.
Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study
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Angela Boggero Alberto Basset Martina Austoni Enrico Barbone Luca Bartolozzi Isabella Bertani Alessandro Campanaro Antonella Cattaneo Fabio Cianferoni Giuseppe Corriero Ambrosius Martin Dörr A. Concetta Elia Gentile Francesco Ficetola Lyudmila Kamburska Gianandrea La Porta Sara Lauceri Alessandro Ludovisi Elda Gaino Enzo Goretti Massimo Lorenzoni Marina Manca Aldo Marchetto Giuseppe Morabito Francesco Nonnis Marzano Alessandro Oggioni Cataldo Pierri Nicoletta Riccardi Giampaolo Rossetti Nicola Ungaro Pietro Volta Silvia Zaupa Diego Fontaneto 《水产资源保护:海洋与淡水生态系统》2014,24(6):841-852
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66.
Gaetano Laghetti Girolamo Fiorentino Karl Hammer Domenico Pignone 《Genetic Resources and Crop Evolution》2009,56(8):1163-1170
In 1970s it was thought that two species of ‘farro’, namely emmer (Triticum dicoccon Schrank) and einkorn (T. monococcum L.), were no longer present in Italy, but in 1981, some populations were discovered in a mountain area of the Appennino Sannita
(central southern Italy). In 2006/2007 three monitoring missions were carried out to check the current situation of these
ancient hulled wheats, specifically in the same areas where they were formerly collected. The same zones were also investigated
by both paleo-ethnobotany and agrobiodiversity points of view. The results of this research have shown that nowadays einkorn
is completely extinct while emmer is still cultivated in very few traditional farms, mainly as a fodder crop. A strong genetic
erosion was detected also for emmer and several nowadays samples were contaminated by seeds of modern spelt (T. spelta L.) varieties. In the present study the causes of this genetic erosion and which safeguarding actions to be undertaken are
discussed. 相似文献
67.
Edith K. Hüttner Fabio Dal Bello Emanuele Zannini Jean Titze Steffen Beuch Elke K. Arendt 《Cereal Chemistry》2011,88(6):602-608
The breadmaking potential of six oat varieties was compared with and related to their physicochemical properties. The most significant differences in the bread characteristics were found in the crumb structure. The varieties Buggy, Energie, and Zorro resulted in good bread quality with an even gas‐cell distribution characterized by a high number of relatively small pores. In contrast, Typhon, Ivory, and Nord 08/311 each had a large hole in the center of the crumb and accordingly poor quality. Breads differed little in specific volume, bake loss, and density. Rheological analysis revealed positive effects of low batter resistance to deformation on oat bread quality. On the basis of the physicochemical characterization, protein and fat contents were identified as key factors responsible for differences observed in bread quality, provided that starch damage and water‐hydration capacity were low. Additionally, high setback and final viscosity, as determined by Rapid Visco Analyser (RVA) analysis, positively affected oat bread quality. High α‐amylase activity was found to influence negatively the breadmaking performance of oats. Overall, protein, fat, dietary fiber content, starch pasting properties, and α‐amylase activity were responsible for the breadmaking properties of oat varieties. 相似文献
68.
Cefarelli G D'Abrosca B Fiorentino A Izzo A Mastellone C Pacifico S Piscopo V 《Journal of agricultural and food chemistry》2006,54(3):803-809
Forty-three secondary metabolites were isolated and characterized from cv. Annurca apple fruit, an apple variety cultivated in the south of Italy. This apple cultivar undergoes a typical reddening treatment after collection. All of the compounds were characterized on the basis of their spectroscopic data. The compounds were tested for their radical-scavenging and antioxidant activities by measuring their capacity to scavenge DPPH* (2,2'-diphenyl-1-picrylhydrazyl radical), H2O2, and NO (nitric oxide) and to inhibit the formation of methyl linoleate conjugated diene hydroperoxides or TBARS (thiobarbituric acid reactive species). 相似文献
69.
Alessandra Roncarati Mariasilvia D'Andrea Fabio Pilla Alberto Felici Paolo Melotti 《Aquaculture Research》2013,44(7):1140-1151
A trial was conducted to evaluate the growth performance and survival of Chelidonichthys lucerna. A total of 13 352 180‐days old juveniles (5.5 ± 2 g; 5 ± 1 cm) were reared at two different densities (A‐EXP = 68 fish m?3; B‐FFA = 15 fish m?3) in eight tanks (four tanks per group) for 360 days. The welfare status and meat quality of fish were evaluated for the A‐EXP and B‐FFA groups in comparison with wild‐caught fishery gurnard (C‐WID). The survival rate was high for both A‐EXP (79%) and B‐FFA (93.5%). B‐FFA fish had the highest specific growth rate (1.16 vs. 1.07; P < 0.05), and were heavier than A‐EXP fish (321 ± 40 g vs .239 ± 44 g; P < 0.01). Rearing conditions did not affect blood metabolites, except for glucose concentrations, which were higher in C‐WID (P < 0.05). The meat quality traits showed that reared groups were fatter (2.8–3.2%) than C‐WID (0.94%); total n‐3 fatty acids (19.02–19.26%) were lower in reared groups than C‐WID (29.99%); and EPA + DHA were similar in all groups (15.1–16.61% vs. 27.99%). Despite the good growth and survival, the final mean weight was below that requested by the market (400–500 g). Future research efforts should focus on reducing the feed conversion rate (3:1). 相似文献
70.
Fabio Minervini Daniela PintoRaffaella Di Cagno Maria De AngelisMarco Gobbetti 《Journal of Cereal Science》2011,54(3):296-304
The use of sourdough, even in combination with cryoprotectant (skim milk, sucrose and trehalose), conventional additives (guar gum, diacetyl tartaric acid esters of monoglycerides, ascorbic acid), honey or fructose and glucose, in frozen dough technology was investigated. After frozen storage, the leavening performance of doughs, and the hardness and texture of breads were compared to those of an unfrozen dough, and to those of a conventional frozen dough. All frozen doughs showed a longer fermentation time and a lower volume increase, with respect to unfrozen dough. When sourdough was combined with cryoprotectant, honey or both, the leavening performance improved compared to the use of sourdough alone. Compared to the conventional frozen dough, higher leavening performance was reached combining sourdough with cryoprotectant alone or together with honey. Sourdough combined with honey, fructose and glucose, honey and cryoprotectant, or conventional additives decreased bread hardness compared to the unfrozen dough bread and to the conventional frozen dough bread. Independently from the use of sourdough, conventional additives allowed to reach a specific volume not significantly different from that of unfrozen dough bread, and breads containing honey were characterized by low values of hardness and by high values of red index. 相似文献