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排序方式: 共有218条查询结果,搜索用时 406 毫秒
71.
Ilaria Marotti Alessandra Bonetti Maurizio Minelli Pietro Catizone Giovenni Dinelli 《Genetic Resources and Crop Evolution》2007,54(1):175-188
Randomly amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR) and a semi-random PCR system were used to analyze
the genetic diversity of 16 Italian common bean landraces and their relationship to four commercial cultivars. Of the primers
tested, 8 ISSR, 6 RAPD and 7 semi-random primers produced polymorphic and reproducible DNA fragments. A higher proportion
of polymorphic bands were observed using ISSR (85%) and semi-random (90%) primers than RAPD (69%) method. The combination
of any two semi-random markers allowed the identification of all 20 bean genotypes. In contrast ISSR (except for primer (CAC)3GC) and RAPD markers appeared to be less informative as more than two markers were necessary to achieve the same diagnostic
level. Moreover, 7 ISSR, 2 RAPD and 8 semi-random exclusive bands were identified as putative population-specific markers.
Semi-random and ISSR derived dendrograms showed similar tendencies in terms of genetic relatedness, whereas clustering of
genotypes within groups was not similar when compared with the RAPD technique. Despite the different ability to resolve genetic
variation among the investigated landraces, two major clusters with less than 60% (ISSR) and 40% (RAPD and semi-random) genetic
similarity were formed with all three marker systems. The two groups were correlated with the phaseolin patterns and seed
size of the landraces. The analysis showed that the cultivar ȁ8Lingua di Fuocoȁ9 and most of the landraces (13 out of 16)
collected in Italy belong to the Andean gene pool, whereas only the three populations from Pratomagno belong to the Middle
American gene pool. 相似文献
72.
Ferlazzo AM Bruschetta G Di Pietro P Medica P Notti A Rotondo E 《Veterinary research communications》2011,35(8):521-530
The aim of this study was to provide basal values of phospholipid (PL) composition in different animal species by 31P NMR analysis using detergents. This fast and accurate method allowed a quantitative analysis of PLs without any previous separation. Plasma and erythrocyte membrane PLs were investigated in mammals (pig, cow, horse). Moreover, for the first time, the composition of plasma PLs in avian (chicken and ostrich) was performed by 31P NMR. Significant qualitative and quantitative interspecies differences in plasma PL levels were found. Phosphatidilcholine (PC) and sphingomyelin (SPH) levels were significantly higher (P < 0.001) in chicken plasma than all the other species tested. In erythrocytes, cow PC and phosphatidylcholine diarachidoyl were significantly lower (P < 0.001) than for pigs and horses, whereas pig PC presented intermediate values among cows and horses. Inorganic phosphate and 2,3-diphosphoglycerate levels were also significantly different between the species under investigation. The [SPH/total PLs] molar ratios in erythrocytes confirmed interspecies differences in phospholipid composition while the PC/SPH molar ratios could be related to a distinct erythrocyte flexibility and aggregability. Diet and nutrition may contribute primarily to the interspecies differences in plasma PL amounts detected. Significant differences between chicken plasma PC and SPH levels and those of the other animal species could be ascribed to a fat metabolism specific to egg production. 相似文献
73.
Rocculi P Sacchetti G Venturi L Cremonini M Dalla Rosa M Pittia P 《Journal of agricultural and food chemistry》2011,59(15):8265-8271
The effect of water on "antiplasticization" and plasticization of green and roasted coffee was studied by textural analysis, sorption isotherms, differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). From BET monolayer value to a(w) = 0.61 and 0.75 for green and roasted coffee, respectively, the solid matrix hydration occurred and water induced hardening. Very short NMR T(2) values and the concomitant absence of any DSC endothermic peak assignable to water freezing were observed at these a(w) values. When solid matrix hydration was completed, water started to act as a plasticizing agent, the compressive modulus started to decrease, and NMR revealed the appearance of a new proton pool with increased mobility. According to DSC, only when the plasticizing effect became important did water present enough mobility to freeze. Above this moisture value (a(w) = 0.78 and 0.86 for green and roasted coffee, respectively), water determined a decrease of bean hardness and a further decrease of the elastic modulus. 相似文献
74.
Massimini G Mastellone V Britti D Lombardi P Avallone L 《Journal of the American Veterinary Medical Association》2007,231(12):1873-1877
OBJECTIVE: To evaluate the effect of passive transfer status (determined from measurements of serum IgG concentration at 24 hours after parturition [sIgG-24]) on preweaning growth performance in dairy goat kids. DESIGN: Prospective observational study. ANIMALS: 20 healthy nursing dairy doe kids in a natural nonintensive breeding environment. PROCEDURES: For each kid, sIgG-24 was measured. Body weight was measured at birth and at the time of weaning 30 days (ie, 29 to 31 days) after birth; average daily gain from birth to day 30 and weight at day 30 were used as measures of preweaning growth performance. Regression analysis was used to evaluate associations between sIgG-24 and measures of preweaning growth performance. RESULTS: Mean +/- SD sIgG-24 was 31.7 +/- 10.3 mg/mL. Mean body weights at birth and weaning were 4.105 +/- 0.981 kg (9.031 +/- 2.158 lb) and 9.310 +/- 2.554 kg (20.482 +/- 5.619 lb), respectively; average daily gain was 0.174 +/- 0.072 kg/d (0.383 +/- 0.158 lb/d). No significant association was detected between sIgG-24 and birth weight. However, sIgG-24 was significantly associated with average daily gain (R(2) = 0.48) and weight at day 30 (R(2) = 0.56). Each increase in sIgG-24 of 1 mg/mL was associated with an increase in average daily gain of 0.005 kg/d (0.011 lb/d) and an increase in weight at day 30 of 0.185 kg (0.407 lb). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that passive transfer status (determined as sIgG-24) was a significant source of variation in preweaning growth performance in dairy doe kids reared in this nonintensive breeding environment. 相似文献
75.
Márcio de Oliveira Marques Fábio Morotti Camila Bizarro da Silva Mario Ribeiro Júnior Rubens César Pinto da Silva Pietro Sampaio Baruselli Marcelo Marcondes Seneda 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(3):367-371
This study was conducted to evaluate the influence of category (heifers, primiparous or multiparous cows) on pregnancy rates in a large scale resynchronization ovulation program. Nelore heifers (n = 903), primiparous lactating cows (n = 338) and multiparous lactating cows (n = 1,223) were synchronized using a conventional protocol of estradiol/P4-based fixed-time artificial insemination (FTAI). Thirty days after ultrasonography, females who failed the first FTAI were resynchronized with the same hormonal protocol prior to a second FTAI. The pregnancy status of each cohort was evaluated by ultrasonography 30 days after each FTAI. The average conception rate after the first FTAI and resynchronization was 80.5%. Heifers had a higher conception rate (85%) than primiparous (76%) or multiparous cows (78%; p = 0.0001). The conception rate after the first FTAI was similar among heifers (57%), primiparous cows (51%) and multiparous cows (56%; p = 0.193). After the second FTAI, heifers exhibited a higher conception rate (66%) than primiparous or multiparous cows (51%; p = 0.0001). These results demonstrate the feasibility of resynchronization in large beef herds for providing consistent pregnancy rates in a short period of time. We also demonstrated that ovulation resynchronization 30 days after FTAI is particularly effective for heifers, providing a conception rate of up to 66%. 相似文献
76.
Cuomo CA Güldener U Xu JR Trail F Turgeon BG Di Pietro A Walton JD Ma LJ Baker SE Rep M Adam G Antoniw J Baldwin T Calvo S Chang YL Decaprio D Gale LR Gnerre S Goswami RS Hammond-Kosack K Harris LJ Hilburn K Kennell JC Kroken S Magnuson JK Mannhaupt G Mauceli E Mewes HW Mitterbauer R Muehlbauer G Münsterkötter M Nelson D O'donnell K Ouellet T Qi W Quesneville H Roncero MI Seong KY Tetko IV Urban M Waalwijk C Ward TJ Yao J Birren BW Kistler HC 《Science (New York, N.Y.)》2007,317(5843):1400-1402
We sequenced and annotated the genome of the filamentous fungus Fusarium graminearum, a major pathogen of cultivated cereals. Very few repetitive sequences were detected, and the process of repeat-induced point mutation, in which duplicated sequences are subject to extensive mutation, may partially account for the reduced repeat content and apparent low number of paralogous (ancestrally duplicated) genes. A second strain of F. graminearum contained more than 10,000 single-nucleotide polymorphisms, which were frequently located near telomeres and within other discrete chromosomal segments. Many highly polymorphic regions contained sets of genes implicated in plant-fungus interactions and were unusually divergent, with higher rates of recombination. These regions of genome innovation may result from selection due to interactions of F. graminearum with its plant hosts. 相似文献
77.
78.
Summary Ten collecting missions in South Italy together with an intensive study of literature sources allowed the compilation of a checklist of the cultivated plant species of south Italy. This checklist contains 540 taxa belonging to 520 different species. The alphabetically ordered articles for the taxa contain the botanical name, the plant family, Italian folk names, information about the distribution in the area referring to the regions, data on collections during our missions indicating the regions, too, details of plant uses and references to relevant, mostly Italian literature sources, including reports from our own explorations and papers based on the material collected. Three appendices provide indexes of synonyms and folk names, respectively, with reference to the accepted botanical names, and an index of families and genera. The information given in this checklist was extracted from a database of the cultivated plants of South Italy, a microcomputer-based system. The checklist is a useful tool for further plant genetic resources exploration in Italy, but may be also of interest for ethnobotanists and other researchers engaged in cultivated plants.
Liste der Kulturpflanzen Süditaliens
Zusammenfassung Zehn Sammelreisen in Süditalien und ein intensives Literaturstudium ermöglichten die Zusammenstellung einer Liste der Kulturpflanzen Süditaliens. Diese Liste enthält 540 Taxa, die 520 verschiedenen Arten angehören. Die alphabetisch geordneten Artikel über die einzelnen Taxa enthalten den botanischen Namen, die Pflanzenfamilie, italienische Volksnamen, Verbreitung im Gebiet nach Regionen aufgeführt, Aufsammlungen während unserer Sammelreisen ebenfalls auf die Regionen bezogen, Angaben über die Nutzung der Pflanzen und Verweise auf wichtige, meist italienische Literaturquellen, einschließlich der Berichte über unsere eigenen Sammelreisen und von Arbeiten, die sich auf unserem Sammelmaterial begründen. Drei Register gestatten das Aufsuchen von Informationen in der Liste nach Synonymen bzw. nach Volksnamen, mit Verweis auf den akzeptierten Namen, und nach Familien und Gattungen. Die in der Liste enthaltene Information wurde aus einer Datenbank der Kulturpflanzen Süditaliens, einem mikrocomputer-gestützten System, ausgewählt. Die Liste kann für die weitere Erfassung pflanzlicher genetischer Ressourcen in Italien nützlich, aber auch für Ethnobotaniker und andere Wissenschaftler, die sich mit Kulturpflanzen befassen, interessant sein.
. 540 , 520 . , , , , , , , , , , . , , . . , , .相似文献
79.
Vrhovsek U Masuero D Gasperotti M Franceschi P Caputi L Viola R Mattivi F 《Journal of agricultural and food chemistry》2012,60(36):8831-8840
Compelling evidence of the health benefits of phenolic compounds and their impact on food quality have stimulated the development of analytical methods for the identification and quantification of these compounds in different matrices in recent years. A targeted metabolomics method has been developed for the quantification of 135 phenolics, such as benzoates, phenylpropanoids, coumarins, stilbenes, dihydrochalcones, and flavonoids, in fruit and tea extracts and wine using UPLC/QqQ-MS/MS. Chromatography was optimized to achieve separation of the compounds over a period of 15 min, and MRM transitions were selected for accurate quantification. The method was validated by studying the detection and quantification limits, the linearity ranges, and the intraday and interday repeatability of the analysis. The validated method was applied to the analysis of apples, berries, green tea, and red wine, providing a valuable tool for food quality evaluation and breeding studies. 相似文献
80.
Controlled reproduction in Anguilla anguilla (L.): comparison between spontaneous spawning and stripping‐insemination approaches 下载免费PDF全文
Andrea Di Biase Antonio Casalini Pietro Emmanuele Michaela Mandelli Pieter Mark Lokman Oliviero Mordenti 《Aquaculture Research》2016,47(10):3052-3060
This study aimed to compare the fertility of eggs between artificially matured female silver eels that spawned spontaneously and those that were spawned by manual stripping. The effects of the two methods of spawning on ovulation and fertilization rate were also investigated. For this purpose, 18 wild female European eels captured in Bonello lagoon (North Adriatic Sea) were carp pituitary extract‐injected to undergo sexual maturation and ovulation; a final injection of 17,20β‐dihydroxy‐4‐pregnen‐3‐one (DHP) was administered when at least 30% of the oocytes were fully transparent. After the DHP‐injection, nine eels were transferred to a new closed recirculating aquaculture system, where they were housed with spermiating males (sex ratio 4/1) to allow spontaneous spawning (SPT‐group); the remaining nine eels were transferred to a 250 L tank and ovulation was checked at four‐hourly intervals by manual stripping (STR‐group). The number of eggs per female in the SPT‐group was significantly greater than that in the STR‐group. Furthermore, fertilization rates in the SPT‐group were notably higher than those observed in the STR‐group. Significantly, the best performances were obtained among eels in which at least 50% of oocytes were fully transparent at the time DHP was administered. We conclude that the fertility of eggs from spontaneously spawning eels is superior to that of eggs acquired by strip‐spawning and artificial fertilization. 相似文献