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21.
ABSTRACT: One hundred and four scrapie positive and 77 negative goats from 34 Greek mixed flocks were analysed by prion protein gene sequencing and 17 caprine scrapie isolates from 11 flocks were submitted to molecular isolate typing. For the first time, the protective S146 variant was reported in Greece, while the protective K222 variant was detected in negative but also in five scrapie positive goats from heavily infected flocks. By immunoblotting six isolates, including two goat flockmates carrying the K222 variant, showed molecular features slightly different from all other Greek and Italian isolates co-analysed, possibly suggesting the presence of different scrapie strains in Greece.  相似文献   
22.
Neurons with similar morphology and neurotransmitter content located at a specific brain region may be part of the same or functionally separate networks. To address the question whether morphologically similar neurons have similar structural architecture at the chromosomal level, we studied Purkinje neurons in the cerebellum. Previous studies have shown that in Purkinje neurons centromeres of several chromosomes form clusters and that the number and size of these clusters remain stable in the adult brain. We examined whether the same set of centromeres form clusters in all the Purkinje neurons. Fluorescent in situ hybridization (FISH) with chromosome-specific para-centromeric probes provided an indirect evidence for a trend towards varying contributions from different chromosomes forming the centromeric clusters in adjacent Purkinje neurons. The results of the study indicate that the individual Purkinje neurons are likely unique in inter-chromosomal spatial associations.  相似文献   
23.
Sesame seeds are an excellent food and non-food raw material, for which there is a consolidated deficit in Italy and in other European Union countries. For this reason, a 2-years experiment was conducted in Sicily to compare the agronomic performance (phenology, morphological and productive traits) and grain quality (oil and its main constituents, protein of defatted flour, fibre) of three landraces, one of Turkish origin and two Sicilian (“Ispica” and “Modica”), and two improved varieties (‘Pachequino’ and ‘Yori 77’). The landraces evidenced earliness (115 days) and the greater height of insertion of first capsule (0.52 m), whereas the variety ‘Pachequino’ was the most productive (3.5 t ha?1). Turkish and “Ispica” landraces and ‘Yori 77’ variety provided seeds with greater lipid (54 %, on average) and protein contents (44 % on defatted flour, on average). ‘Pachequino’ and both Sicilian landraces produced seeds richer in fibre fractions. As regard to oil quality, the oleic acid/linoleic acid was found balanced (about 1) for Turkish landrace, and it decreased for the other cultivars reaching the lowest value for ‘Pachequino’. “Modica” had higher quantity of unsaponifiable matter (1.98 %) in the oil, whereas ‘Yori 77’ had the maximum concentration of phytosterols (5532.8 mg kg?1). Policosanol fraction prevailed in oil of “Ispica” (205.8 mg kg?1). Moreover, there was variability in the fatty acid, sterol and policosanol compositions with differences among the cultivars. Research provide information to exploit sesame within agrosystems under Mediterranean climates, and may be a starting point for breeding activity to enhance crop productivity and grain quality.  相似文献   
24.
Evidence from research in the Pripyat catchment, reviewed here, indicates that under the ecological conditions prevalent in this area, radiocaesium (137Cs) is highly mobile in both river water and poorly drained organic soils. Data collected at three different spatial and temporal scales demonstrate the effects of hydrological events on 137Cs mobility. During the period 1988–1994, 137Cs contamination in some poorly drained organic soils in the Pripyat catchment and in the milk from cows grazing on these soils are generally declining much faster than the radioactive half life. However, sharp increases in levels of 137Cs in both floodplain soils and milk to 2–3 times that observed immediately after the initial deposition have been measured immediately after summer floods. The processes causing these observed changes have not yet been fully explained but the sites where enhanced 137Cs mobility has been detected are clearly associated with the spatial patterns of organic soils and river flooding.  相似文献   
25.
Conservation of apex predators is a key challenge both in marine and terrestrial ecosystems. The white shark is a rare but persistent inhabitant of the Mediterranean Sea and it is currently assessed as “critically endangered” in the region. However, the population trends and dynamics of this species in the area are still unknown. Little is known about white shark distribution, habitat use and population abundance trends, aspects that are critical for conservation and management. In this study, we built the most comprehensive database of white shark occurrence records in the region. We collected 773 different records from different sources and used them to characterize the spatial and temporal patterns of abundance of Mediterranean white sharks between 1860 and 2016. We analysed these data by using generalized additive models and used spatially disaggregated information on human population abundance as a proxy of observation effort. Our results suggest a complex trajectory of population change characterized by a historical increase and a more recent reduction (61%, range 58%–72%) since the second half of the 20th century. In particular, analyses reveal a 52% (range 37%–88%) to 96% (range 92%–100%) overall decline in different Mediterranean sectors and a contraction in spatial distribution. Here, we provide the first reconstruction of abundance trends and offer new hypotheses regarding the drivers of change of white sharks in the Mediterranean. Our approach can be broadly applied to data‐poor contexts to reconstruct change and inform the conservation of endangered top predators in the Mediterranean Sea and other intensely used marine regions.  相似文献   
26.
Mitochondrial DNA (mtDNA) sequences from 686 wild and domestic pig specimens place the origin of wild boar in island Southeast Asia (ISEA), where they dispersed across Eurasia. Previous morphological and genetic evidence suggested pig domestication took place in a limited number of locations (principally the Near East and Far East). In contrast, new genetic data reveal multiple centers of domestication across Eurasia and that European, rather than Near Eastern, wild boar are the principal source of modern European domestic pigs.  相似文献   
27.
A 25-year-old gelding sport horse was referred for the treatment of recurring bilateral anal amelanotic melanoma. On physical examination, the horse presented bilateral poorly delimited perianal masses that recurred 2 months after surgical excision. The owner elected the lesions to be treated with surgery combined with electrochemotherapy using the drug cisplatin. The two masses were removed, and the surgical bed was treated with electrochemotherapy. A second session was performed 3 weeks later. The horse remained disease-free for 5 months and then experienced a marginal recurrence in one side. The nodule was re-treated, and the horse remained disease-free for 2 additional months, when it died of abdominal metastases. Electrochemotherapy can be added to the current strategies to palliate recurrent melanomas in horses.  相似文献   
28.
OBJECTIVE: To determine survival rate, complications, and short-term fertility rate after fetotomy in mares. DESIGN: Retrospective study. ANIMALS: 72 mares with severe dystocia. PROCEDURES: Records from 1991 to 2005 were searched for mares with dystocia in which a fetotomy was performed. Data relating to presentation and position of foals; survival rate, complications, and short-term fertility rate in mares; and 45-day pregnancy rate in mares bred 2 to 3 months after fetotomy were recorded. RESULTS: Anterior fetal presentation was detected for 54 of 72 (75%) mares, posterior presentation was detected for 13 (18.1%), and transverse presentation was detected for 5 (6.9%). One fetus in anterior presentation was hydrocephalic. Survival rate after fetotomy was 95.8%. Complications included retained fetal membranes (5.5%), laminitis (6.9%), vaginal and cervical lacerations (2.8%), and delayed uterine involution (2.8%). Mares bred 2 to 3 months after fetotomy had good short-term fertility, with a mean pregnancy rate of 79.4% at 45 days after breeding. CONCLUSIONS AND CLINICAL RELEVANCE: The survival rate was high, compared with rates reported after cesarean section, and short-term fertility rate was similar to those reported for mares that had a controlled vaginal delivery or cesarean section. Fetotomy performed by a skilled veterinarian on a nonviable fetus should be considered as a means of quick and safe correction of dystocia that does not necessarily impair short-term fertility in affected mares.  相似文献   
29.
Water, Air, & Soil Pollution - Mobilization of arsenic (As) in the subsurface environment can result in elevated concentrations of As in groundwater and potential human exposure and adverse...  相似文献   
30.
Summary The influence of strong alkaline attack on the elastic modulus of beech wood was investigated from a physico-chemical point of view. It was shown that by treating rather large samples with 24% caustic potash solution, part of the hemicelluloses and lignin is removed; also wood shrinks more that three times as much as normally. This has no effect on the net cell wall elastic properties of the wood in spite of statements by other authors on milder treatment. It is supposed that such a treatment triggers a dissolution of the so-called sparingly-soluble hemicelluloses up to an extent by which wood is densified without loosing its structure. Further investigations will be carried out on the general properties of wood subjected to this kind of treatment.  相似文献   
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