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181.
Nine genic SSR loci were used to evaluate the genetic diversity and identify accessions in wild Italian Humulus lupulus L., in comparison with widely cultivated European and U.S. commercial cultivars. A collection of 80 wild hop samples from Italy and 43 hop cultivars from Europe and U.S., were characterized. Allelic frequency analysis revealed 65 distinct Italian genotypes and differentiated all the commercial cultivars; moreover, specific alleles were observed for wild and cultivated hops. The number of alleles identified in the wild population were 104 and 123 within all the accessions. The maximum polymorphic information content was evidenced for locus HlGA23 in the Italian wild population and in the whole set of accessions (0.905 and 0.902 respectively). The dendrogram constructed from Euclidean distance with the UPGMA method showed two main clusters, one including commercial American and European accessions and one mostly composed by wild Italian accessions. Model-based clustering (Bayesian method) placed the accessions into five germplasm groups, one of which was characterized by Italian genotypes only. The study showed for the first time the great biodiversity present in Italy, and the remarkable differences with European and American hops. It was also found that within the population of north-central Italy a large genetic variability is present, suited to be studied and exploited; this genetic wealth could be used in future breeding programs in order to develop new hop varieties carrying characteristics useful for brewers.  相似文献   
182.
In this study changes in hematochemical parameters, milk composition and yield were investigated in buffaloes during the transition period. A total of 93 buffaloes 113.9 ± 8.03 months old and 535 ± 50 kg average body weight were used. Parity was recorded, blood samples were collected from 80 days pre‐partum until 70 days post‐partum; milk samples were collected from 5 days to 70 days post‐partum. On serum samples, the values of non‐esterified fatty acids, β‐hydroxybutyrate, glucose, cholesterol, triglycerides, aspartate aminotransferase, alanine aminotransferase, gamma‐glutamyltransferase, urea, total proteins were evaluated. On milk, percentage of fat, protein and lactose, along with the somatic cell count (SCC), milk yield and daily milk production (DMP) were assessed. The peripartum period significantly (P ≤ 0.01) influenced all studied parameters with the exception of glucose. Milk fat percentage showed decreasing trend from 10 until 40 days post‐partum; DMP significantly (P ≤ 0.01) increased from 1 day post‐partum until 40 days post‐partum. Milk yield significantly (P ≤ 0.01) decreased in animals over the sixth lactation. Our results confirmed the importance of transit period in buffaloes. Blood parameters and milk composition alterations are crucial to predict the energy balance status of buffaloes in order to improve their management and feed intake during the transition period.  相似文献   
183.
Limited information is available on suitable height of transport crates for turkeys. We compared behaviors and physiological indicators of four groups of 10 female turkeys each confined in either conventional (38.5 cm height) or experimental (77 cm height) crates during six commercial pre‐slaughter transportations for 86 km (76 ± 4 min) along two tracts with one‐lane streets, crossroads, bends, roundabouts (S1 and S2) and a highway tract (H) between S1 and S2. Only 36% of birds in the higher crates maintained a standing position. In conventional versus experimental crates, the frequency of rising attempts was five/bird/hour versus less than one/bird/hour, while wing flapping was seven/bird/hour versus 20/bird/hour, and balance loss was one versus four/bird/hour. The behaviors of both groups differed significantly according to the route tract, with a lower frequency of stress‐related behaviors at H. No scratches, fractures or hematomas were detected in any birds after transportation. Crate height had no significant effect on hemato‐biochemical markers. These results suggest that crates enabling a standing position may increase potentially dangerous behaviors. Moreover, busy and curvy routes should be avoided, as they may contribute to increasing the frequency of stress‐related behaviors.  相似文献   
184.
185.
The role of deadwood on biodiversity conservation of forest ecosystems is widely recognised. Interest on deadwood has increased in the last years, and forest management policy regards deadwood as indicator of sustainable forest management.  相似文献   
186.
Rapid glacier retreat often results in extensive areas of deglaciated terrain where primary successional processes occur. We studied biotic and abiotic factors underlying the invasion of larch (Larix decidua Mill.) on a glacier foreland and tested the hypothesis that the pattern of its establishment was controlled primarily by terrain age.  相似文献   
187.
OBJECTIVE: To document effects of cisplatin on regenerate bone formation during the distraction and consolidation phases of bone transport osteogenesis. ANIMALS: 10 skeletally mature hounds. PROCEDURES: Bone transport osteogenesis was performed to reconstruct a 3-cm defect in the radius of each dog. Five dogs were randomly selected to receive cisplatin (70 mg/m2, IV, q 21 d for 4 cycles), and 5 were administered saline (0.9% NaCl) solution. Bone mineral density was measured by use of dual-energy x-ray absorptiometry (DEXA) on days 24, 55, and 90 after surgery. Dogs were euthanatized 90 days after surgery. Histomorphometry was performed on nondecalcified sections of regenerate bone. Bone mineral density and histomorphometric indices of newly formed bone were compared between groups. RESULTS: Densitometric differences in regenerate bone mineral density were not detected between groups at any time period. Cisplatin-treated dogs had decreased mineralized bone volume, decreased percentage of woven bone volume, decreased percentage of osteoblast-covered bone, increased porosity, and increased percentage of osteoblast-covered surfaces, compared with values for control dogs. Lamellar bone volume and osteoid volume did not differ significantly between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Regenerate bone will form and remodel during administration of cisplatin. Results of histomorphometric analysis suggest that bone formation and resorption may be uncoupled in cisplatin-treated regenerate bone as a result of increased osteoclast activity or delayed secondary bone formation during remodeling. These histomorphometric differences were modest in magnitude and did not result in clinically observable complications or decreased bone mineral density as measured by use of DEXA.  相似文献   
188.

Large and severe disturbances may erode the resilience of temperate forest ecosystems and alter their recovery dynamics, especially under global change. We investigated mid-term recovery in mixed mountain forests in Slovenia after three independent severe windstorms in 2008 created large disturbed patches. Across a network of 102 permanent plots and three inventories over the 11-year post-disturbance period, we monitored trends in density, composition, and structure of regeneration, which are key indicators of forest resilience. Ecological drivers of regeneration, including topography, microsites, and biotic interactions, were analysed using linear mixed models. We quantitatively assessed physiognomic recovery by comparing regeneration densities with the restocking target used in forest practice, and compositional recovery by comparison with pre-disturbance stand composition. Regeneration densities and structure tended to converge among post-disturbance treatments (planting vs. natural regeneration) 11 years post-disturbance, as density of natural regeneration substantially dropped between the second and third inventory. Some drivers of recovery (i.e. ground vegetation and distance to the forest edge) varied over time, while the effect of elevation on regeneration density was consistently negative. The results indicate that the forest sites generally show adequate resilience to large-scale wind disturbances, in terms of physiognomic recovery, but not in terms of rapid compositional recovery, as pioneer and light-demanding tree species increased in share compared to the pre-disturbance stands.

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189.
The canine placenta is an underexamined organ. Placental abnormalities can affect foetus development and may be responsible for a low weight of the infant at birth; however, knowledge on their clinical significance in the canine species is limited. We aimed to describe macroscopic and microscopic findings in the canine placenta and amnion at term in clinically uncomplicated pregnancies and to evaluate their relationship with birth weight of healthy puppies. During natural delivery or C-section, the birth weight of 82 puppies was recorded, 72 placentas and 66 amnions were recovered. The foetal and maternal surfaces of the placental girdle, marginal haematoma and amnion were evaluated. Each gross finding was recorded, morphometrically assessed and sampled for histological diagnosis. Furthermore, specimens of placenta and amnion were collected from representative areas and microscopic deviations from normal structure were evaluated in haematoxylin and eosin sections. Gross examination revealed ‘abnormalities’ in the 75.4% of the collected placentas. Necrosis was the gross change most commonly observed in the placental girdle (72.5%). Congestion (17.4%) and clotted blood/fibrinoid material (2.9%) were also observed. No gross changes of either the marginal haematoma or the amnion were recorded. Histologically, placental girdle showed necrosis (62.3%), mineralization (52.2%), congestion (36.2%) and neutrophilic infiltration (27.5%). Marginal haematoma exhibited mineralization (11.6%) and neutrophils (29%), while necrotic foci were rarely observed (4.3%). In the amnion, the most frequent alteration observed was hypertrophy of the epithelium (35.9%) followed by oedema (31.2%), mineralized foci (28.1%), fibrosis (23.4%), congestion (15.6%) and more rarely neutrophils (12.5%). Puppies’ birth weight was not statistically affected by either gross or histological abnormalities. Our study revealed that macroscopic and microscopic ‘abnormalities’ of the placenta and amnion may be common in uncomplicated pregnancies at term; however, no implications on puppies’ birth weight were observed. Deviations from ‘normal’ morphology of canine foetal adnexa warrant further investigation to assess their clinical implications if present.  相似文献   
190.
Landscape Ecology - Spatially explicit correlates of foliar elemental, stoichiometric, and phytochemical (ESP) traits represent links to landscape patterns of resource quality. We investigate...  相似文献   
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