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51.
Summary The study of the structural organization of the eukaryotic genome is one of the most important tools for disclosing the evolutionary relationships between species.Artemia (Crustacea, Phyllopoda) offers a very interesting model for speciation studies. The genus, distributed all over the world, comprises both bisexual sibling species and parthenogenetic populations, exhibiting different chromosome numbers (diploidy, polyploidy, and heteroploidy).Digestion of genomic DNA of the parthenogeneticArtemia sp. from Tsing-Tao (China) with the restriction enzymes Eco RI and Alu I reveals that a highly repetitive sequence of 133 bp is present. The Eco RI fragment has been cloned and characterized by genomic organization. The distribution of the Eco RI family of repeats was also studied in several bisexual and parthenogeneticArtemia populations and compared with an Alu I repetitive fragment previously identified inArtemia franciscana.  相似文献   
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The development of specific and individualized training programs is a possible way to improve athletic performance and minimize injuries in professional athletes. The information regarding the sport's physical demands and the athletes’ physical profile have been, so far, considered as exhaustive for the design of effective training programs. However, it is currently emerging that the genetic profile has to be also taken into consideration. By merging medical and genetic data, it is thus possible to identify the athlete's specific attitude to respond to training, diet, and physical stress. In this context, we performed a study in which 30 professional soccer players, subjected to standard sport medical evaluation and practices, were also screened for genetic polymorphism in five key genes (ACTN3, COL5A1, MCT1, VEGF, and HFE). This genetic analysis represents the central point of a multidisciplinary method that can be adopted by elite soccer teams to obtain an improvement in athletic performance and a concomitant reduction of injuries by tailoring training and nutritional programs. The genetic fingerprinting of single athletes led to the identification of two performance-enhancing polymorphisms (ACTN3 18705C>T, VEGF-634C>G) significantly enriched. Moreover, we derived a genetic model based on the gene set analyzed, which was tentatively used to reduce athletes’ predisposition to injuries, by dictating a personalized nutrition and training program. The potential usefulness of this approach is concordant with data showing that this team has been classified as the healthiest and least injured team in Europe while covering the highest distance/match with the highest number of high-intensity actions/match.  相似文献   
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Psychological distress is a common consequence of breast cancer diagnosis and treatment and could further exacerbate therapy side effects. Interventions increasing treatment tolerance are crucial to improve both patients' quality of life and adherence to therapies. Virtual reality (VR) has emerged as an effective distraction tool for different medical procedures. Here, we assessed the efficacy of immersive and interactive VR in alleviating chemotherapy-related psychological distress in a cohort of Italian breast cancer patients, also comparing its effects with those of music therapy (MT). Thirty patients were included in the VR group, 30 in the MT group, and 34 in the control group, consisting of patients receiving standard care during chemotherapy. Our data suggest that both VR and MT are useful interventions for alleviating anxiety and for improving mood states in breast cancer patients during chemotherapy. Moreover, VR seems more effective than MT in relieving anxiety, depression, and fatigue.  相似文献   
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We present a new global method for the identification of hotspots in conservation and ecology. The method is based on the identification of spatial structure properties through cumulative relative frequency distributions curves, and is tested with two case studies, the identification of fish density hotspots and terrestrial vertebrate species diversity hotspots. Results from the frequency distribution method are compared with those from standard techniques among local, partially local and global methods. Our approach offers the main advantage to be independent from the selection of any threshold, neighborhood, or other parameter that affect most of the currently available methods for hotspot analysis. The two case studies show how such elements of arbitrariness of the traditional methods influence both size and location of the identified hotspots, and how this new global method can be used for a more objective selection of hotspots.  相似文献   
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Two experimental longline surveys were carried out in the Santa Maria di Leuca (SML) cold-water coral province (Mediterranean Sea) during May–June and September–October 2010 to investigate the effect of corals on fish assemblages. Two types of “megahabitat” characterized by the virtual absence of fishing were explored. One was characterized by complex topography including mesohabitats with carbonate mounds and corals. The other type of megahabitat, although characterized by complex topographic features, lacks carbonate mounds and corals. The fishing vessel was equipped with a 3,000 m monofilament longline with 500 hooks and snoods of 2.5 m in length. A total of 9 hauls, using about 4,500 hooks, were carried out both in the coral megahabitat and in the non-coral megahabitat during each survey. The fish Leucoraja fullonica and Pteroplatytrygon violacea represent new records for the SML coral province. The coral by-catch was only obtained in the coral megahabitat in about 55% of the stations investigated in both surveys. The total catches and the abundance indices of several species were comparable between the two habitat typologies. The species contributing most to the dissimilarity between the two megahabitat fish assemblages were Pagellus bogaraveo, Galeus melastomus, Etmopterus spinax and Helicolenus dactylopterus for density and P. bogaraveo, Conger conger, Polyprion americanus and G. melastomus for biomass. P. bogaraveo was exclusively collected in the coral megahabitat, whereas C. conger, H. dactylopterus and P. americanus were found with greater abundance in the coral than in the non-coral megahabitat. Differences in the sizes between the two megahabitats were detected in E. spinax, G. melastomus, C. conger and H. dactylopterus. Although these differences most probably related to the presence-absence of corals, both megahabitats investigated play the role of attraction-refuge for deep-sea fish fauna, confirming the important role of the whole SML coral province as a refuge area from fishing.  相似文献   
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This paper reviews the existing literature on the age and growth of grenadiers in the Mediterranean Sea and provides new data on ageing of Trachyrincus scabrus in the North-western Ionian Sea (Central Mediterranean). Most studies have been carried out through otolith readings. Seasonal otolith formation also appears to be a general trend in grenadier fish in the Mediterranean even though it seems to be related to fluctuations in feeding and activity patterns. From examined literature age ranges of macrourids in the Mediterranean Sea varied from young-of-the-year (age 0) to a maximum ages of 23 years. There is a general agreement on the growth pattern of the species in the different geographic areas. T. scabrus was collected in the North-western Ionian Sea at depths between 400 and 1200 m during four seasonal trawl surveys. The minimum and maximum sizes of the whole sampled population were between 58 and 217 mm PAL. Otoliths were removed from 216 specimens. Backcalculation was performed and a maximum age of 10 years was determined. The following von Bertalanffy growth parameters were estimated for the whole sampled population: L ?? = 247.44 ± 8.39 mm PAL; k = 0.125 ± 0.010/year; t 0 = ?1.921 ± 0.127.  相似文献   
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