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91.
Characterizing the complexity of landscape boundaries by remote sensing   总被引:9,自引:0,他引:9  
This paper presents a method for characterizing the complexity of landscape boundaries by remote sensing. This characterization is supported by a new boundary typology, that takes into account points where three or more landcovers converge (i.e., convergency points or coverts). Landscape boundary richness and diversity indices were proposed and calculated over 19 landscapes in South-East Brazil. Results showed that landscape boundaries, especially convergency points, provided an enrichment in landscape pattern analysis. Landcover boundary diversities were significantly related to landcover shape: elongated riparian units had the highest values for boundary diversity and coverts proportion indices. On the other hand, landscape analysis showed that indices of shape, richness, diversity and coverts proportion provided an additional evaluation of landcover spatial distribution within the landscape.  相似文献   
92.
The clinical and radiographical features of hip dysplasia in a Persian cat are described. Pectineus myotendonectomy produced only a temporary improvement and coxofemoral excision arthroplasty was performed. This resulted in complete remission of the signs and symptoms.  相似文献   
93.
94.
The efficacy of an oral formulation of ivermectin plus praziquantel in the reduction of nematode and cestode egg counts in horses was assessed in 273 horses under field conditions at 15 sites in North America (n = 6) and Europe (n = 9). Horses were confirmed by fecal examination to have natural infections of strongyles (100%) and tapeworms (76%). Replicates of four horses were formed at each site, and in each replicate three animals received ivermectin (0.2 mg/kg body weight) plus praziquantel (1 mg/kg body weight) oral paste and one animal remained untreated or received vehicle paste. Fecal samples were collected for fecal nematode and cestode egg counting before and 7, 8, 9, 14, 15, and 16 days after treatment. Horses treated with ivermectin plus praziquantel oral paste had significantly (P <.01) lower posttreatment strongylid and cestode egg counts (reductions of 98% or more) than controls. Combined site analyses revealed that 95% or 96% of the horses positive for cestode eggs before treatment that were treated with ivermectin plus praziquantel were negative for cestode eggs at each posttreatment fecal examination. No adverse reactions attributable to ivermectin plus praziquantel oral paste treatments were observed. The results of the studies demonstrated that ivermectin plus praziquantel paste was highly effective in reducing egg shedding by gastrointestinal nematodes and cestodes, and no adverse reactions were observed in horses treated under field conditions.  相似文献   
95.
96.
OBJECTIVE: To investigate age-related variations in results of hematologic and plasma biochemical tests performed on dogs of 2 common breeds. DESIGN: Prospective cohort study. ANIMALS: 34 Beagles and 44 Labrador Retrievers. PROCEDURE: Blood samples were collected throughout the dogs' lives; 589 samples were collected from the Beagles and 964 samples were collected from the Labrador Retrievers (age at the time of sample collection ranged from 22 days to 15 years). White blood cell and RBC counts; hemoglobin concentration; Hct; mean cell volume; mean cell hemoglobin concentration; alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase activities; and calcium, phosphorus, cholesterol, urea, protein, and albumin concentrations were measured. RESULTS: For all tests, there were significant effects of age on test results. There was a significant interaction between age and breed for all tests except hemoglobin, albumin, and phosphorus concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that there were age-related changes in hematologic and plasma biochemical test results in these 2 breeds of dogs. Changes were most evident during the first year of life, reflecting growth and maturation of the puppies. In some instances, values for puppies diverged markedly from those for adults, necessitating the use of age-specific reference ranges for the interpretation of clinical data.  相似文献   
97.
98.
Biological weapons are considered as mass destruction and terror weapons. Terrorism including bioterrorism is the major threat in the future conflicts for our nations. The aim of bioterrorism is more related to the potential disorganisation of the society than to the lethal effects of the agents used. The dramatic consequences cannot be discarded, especially if contagious agents such viral are used. The preparation of specific defence measures is a major challenge for our countries.

The knowledge acquired from the struggle against natural infectious diseases and recent events are essential to improve behaviours to face the biological weapon threats. The defence attitude is based on the anticipation of the threat, the management of the victims, and the restoration of the operational capabilities. This global defence attitude implies six important functions: (i) alert, (ii) detection and diagnosis, (iii) availability of pharmaceutical countermeasures such as vaccine, sera and anti-infectious medicine and products, (iv) medical management of victims, (v) training and information, (vi) research and development.

Passive and active immunoprevention and immuntherapy belong to the approaches discussed in the context of bioterrorism countermeasures. Further researches might be focused on these topics.  相似文献   

99.
A serological survey for bovine viral diarrhoea virus (BVDV) antibodies on a collection of 1295 serum samples obtained from 6-12 months old cattle originating from 45 farms in Slovakia was carried out. On 13 farms more than 90% of the examined animals were seropositive, on 14 farms 71-90% seroprevalence was observed, on 13 farms only 50-70% animals were found to be positive for BVDV antibodies, while the remaining 5 farms showed fewer than 50% seropositive animals. The average incidence of BVDV antibodies (around 70%) was similar as determined 30 years ago. Of 84 serum samples from seronegative animals originating from 14 farms in which 70-98% seropositivity was observed, six were positive in Ag-BVDV ELISA indicating persistently infected (PI) cattle. On a farm to which animals were imported from abroad, a BVD outbreak was observed. Of 110 animals tested, four were positive in Ag-ELISA indicating the presence of PI cattle on this farm. Genetic typing of two isolates from imported animals performed by RT-PCR (324/326 primers from 5'-UTR), sequencing of PCR products and computer-assisted phylogenetic analysis revealed that they belong to BVDV-1 h group.  相似文献   
100.
The thiobarbituric acid reactive substances (TBARS) assay is a commonly used method for the detection of lipid peroxidation. Malondialdehyde is formed as a result of lipid peroxidation and reacts with thiobarbituric acid to form a pink pigment that has an absorption maximum at 532 nm. Other compounds also react with thiobarbituric acid to form colored species that can interfere with this assay, but little is known about these interfering species. This is the first investigation using LC-MS and MS-MS to study the structures of the pink adduct as well as a common unstable yellow interference compound, which absorbs at 455 nm. Also, the presence of barbituric acid impurities in the thiobarbituric acid reagent was found to produce 1:1:1 thiobarbituric acid/malondialdehyde/barbituric acid and 2:1 barbituric acid/malondialdehyde adducts that absorbed at 513 and 490 nm, respectively, indicating that thiobarbituric acid should be purified before use.  相似文献   
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