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1.
Silviculture heading for structural heterogeneity creates many single trees standing at stand margins, inner edges or in remnant tree groups. As they played just a minor role in the age class forest, the growth behaviour of strongly released trees is rather unexplored. Here we show how retention cutting, presently spreading in the boreal of Québec province, affects stem and coarse root growth of remained single black spruce [Picea mariana (Mill.) Britton]. Increment cores from roots and stems of 125 trees show that retention cutting triggers coarse root growth of the remaining trees. Compared with reference trees retention trees accelerate root in relation to stem growth. Mean and variability of the root–stem allometry significantly rise after retention cutting. The found acceleration of root in relation to stem growth means mechanical stabilisation of the retention trees and corroborates the retention cutting method. Evaluation of silvicultural treatments can be incomplete and misleading as long as they are just based on aboveground reactions and neglect root growth.  相似文献   
2.
The isolation of broadly neutralizing antibodies against influenza A viruses has been a long-sought goal for therapeutic approaches and vaccine design. Using a single-cell culture method for screening large numbers of human plasma cells, we isolated a neutralizing monoclonal antibody that recognized the hemagglutinin (HA) glycoprotein of all 16 subtypes and neutralized both group 1 and group 2 influenza A viruses. Passive transfer of this antibody conferred protection to mice and ferrets. Complexes with HAs from the group 1 H1 and the group 2 H3 subtypes analyzed by x-ray crystallography showed that the antibody bound to a conserved epitope in the F subdomain. This antibody may be used for passive protection and to inform vaccine design because of its broad specificity and neutralization potency.  相似文献   
3.
The fungicide fenhexamid [N-(2,3-dichloro-4-hydroxyphenyl)-1-methylcyclohexanecarboxamide] degraded rapidly by UV or sunlight irradiation, yielding 7-chloro-6-hydroxy-2-(1-methylcyclohexyl)-1,3-benzoxazole (CHB) as a main photoproduct. CHB was isolated, and its effect on alcoholic fermentation of Saccharomyces cerevisiae was studied. The results indicate that the presence of CHB does not affect the extent of alcohol production. After 12 days, the amount of CHB in the fermentation medium decreased by ca. 65%. Only 25% of the missing CHB was recovered unchanged from yeasts, most likely because it was adsorbed on the yeast wall cell. The remaining part degraded during the fermentation process. Glucan and chitin, two potential adsorbents, which constitute yeast cell walls, exhibited affinity for CHB.  相似文献   
4.
A crossbreed dog was presented with non-weight bearing on the right hindlimb and a semi-flexed stifle. Clinical examination and radiographic investigation showed a grade 3 medial patellar luxation, characterised by hypoplasia of the medial trochlear ridge. No other significant skeletal abnormalities were detected. A 180 degrees rotation of the femoral trochlea was the surgical technique chosen to treat the trochlear dysplasia, the aim being to move the normal lateral ridge to the medial side and thereby prevent patellar luxation. This technique was able to restore correct conformation of the femoral trochlea and preserve the integrity of the trochlear groove cartilage, thus potentially retarding the progression of degenerative joint disease. The dog recovered fully and postoperative radiographic examinations showed healing of the rotated trochlea with only mild signs of degenerative joint disease.  相似文献   
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Foot health represents an issue in wild avifauna breeding practices. In particular, prevalence of digital ulceration (DU ) and foot pad dermatitis (FPD ) are valid indicators of welfare in wildlife conservation centres and may be interpreted as to fitness for bird's reintroduction into the wild. This study meant to test the effects of raising practices on foot pad health in captive Sardinian partridges (Alectoris barbara barbara Bonnaterre, 1790) reared for biodiversity conservation, to assess welfare and fitness to reintroduction into nature. A total of 22 couples were allotted into two experimental groups. In one group, 10 couples were housed in 10 cages for breeding partridges, consisting of two animals each, with metal wire flooring system, above trays where droppings were collected. The remaining 12 couples were housed in six aviaries, consisting of four animals each, on natural (earth and stones) ground. In both groups, partridges were fed identical diets. No significant differences of food pad scoring were found between birds housed in cages (2.3 ± 0.4) and those reared in aviaries on natural ground (2.5 ± 0.6). Moreover, scores of male foot pads for both groups (2.4 ± 0.6) had no significant differences in comparison with female foot pads, independently on housing (2.5 ± 0.4). Body mass (BM ) was higher (+4.36%) than average BM reported for wild Sardinian partridges. Digital ulceration was found in the 20% of females, exclusively from the cage group. Body mass of females in cages with metal wire flooring appeared to be significantly (p  < .001) and negatively correlated (r  = ?.528) with DU prevalence. These results suggest that housing conditions impacts differently on behaviour of females and males in one same couple, and this relates to foot health, in particular as to DU prevalence.  相似文献   
8.
A modified technique is presented for surgical and diagnostic arthroscopy of the shoulder joint in the dog. The technique involves access to the joint through two points only; one was created in place of the drainage needle-cannula, which was replaced with a portal, while the second was located more caudally compared with previous techniques. Using a changing guide rod system the two portals are completely interchangeable in order to perform easier arthroscopic surgery either in the cranial or caudal aspect of the joint. The presence of only one portal caudal to the lateral collateral ligament allows more freedom of movement and avoids interference between the arthroscope and the instruments. The modified procedure was performed on 33 joints affected by osteochondritis dissecans or tenoligament diseases and facilitated straightforward diagnostic examinations, and simple and rapid surgical procedures.  相似文献   
9.
Clinical and Laboratory Findings in Equine Piroplasmosis   总被引:1,自引:0,他引:1  
The objective of this study was to evaluate equine piroplasmosis (EP) as a cause of morbidity in horses in Sardinia (Italy), describe the clinical signs and altered hematologic and biochemical parameters, and illustrate response to different treatments. Among 44 horses suspected of tick-borne disease, 38 were polymerase chain reaction (PCR) positive for Theileria equi (n = 27) or Babesia caballi (n = 6), whereas five were positive for both protozoans. Typical clinical features of piroplasmosis were seen in some of the horses, whereas others had nonspecific mild symptoms. Hematologic findings revealed involvement of the three blood cell lineages (anemia, leukopenia or leukocytosis, thrombocytopenia), and biochemical variations were related to increased bilirubin, alteration of serum phosphorus, and hypoalbuminemia. We suggest that the two protozoans are the most important causative agents of equine tick-borne disease in this geographic area, and we observe that different clinical features are associated with the disease; in addition to the typical aspects of piroplasmosis, characterized by fever, pale mucous membranes, and icterus, we can signal other nonspecific mild signs such as weight loss, weight loss associated with an insignificant leukopenia, or weight loss associated with depression, anorexia, and mild hyperbilirubin. The study is intended as a practical contribution for veterinary practitioners because it describes different clinical presentations and laboratory findings of EP, suggests diagnostic and therapeutic approaches to the disease, and shows diffusion of the disease in a Mediterranean region.  相似文献   
10.
Leptospirosis is a zoonotic disease of global importance and has a worldwide distribution. This infection displays clear seasonal nature in some regions of the tropics, where the rainy season is marked by high temperatures. Household and wild animals carry leptospires and contribute to their dissemination in nature. Transmission mainly occurs by contact with water contaminated with the urine of infected animals, and consequently, it is quite widespread especially in times of rain, since many areas are subject to flooding and have poor sanitation. Serological tests demonstrate that Leptospira sp. infection in horses occurs worldwide and that the predominant serovar may vary depending on the region or infection sources. Besides systemic and ocular manifestations, leptospirosis in horses has been recognized as an important disease of the reproductive system, since it leads to the birth of weak foals, stillbirths or neonatal mortality, and mainly to abortion, usually after the sixth month of pregnancy. In this context, this review aims to gather and discuss information about the role of leptospirosis in reproductive disorders in horses.  相似文献   
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