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41.
Melanoma is one of the most frequently metastasizing malignant neoplasias. This study examines an experimental model of pulmonary metastasis and the B16F10 cell subline, highly metastatic in the lung. Antimetastatic effects of the flavonoids tangeretin, rutin, and diosmin were analyzed, and at the same time an analysis of the metastatic activity of ethanol was performed, considered to be necessary because it is used as a vehicle for administering the flavonoids. Lentini's model, which complements the macroscopic evaluation of nodule numbers by using a stereoscopic microscope and image analysis at the microscopic level, was used. The greatest reduction in the number of metastatic nodules (52%) was obtained with diosmin; similarly, the percentages of implantation, growth index, and invasion index (79.40, 67.44, and 45.23%, respectively), were all compared with those of the ethanol group, considered to be an effective control group. Rutin- and tangeretin-treated groups also showed reductions of the same index compared with the ethanol group. It would seem that structural factors would better explain these results and the antimetastatic activity of each flavonoid and the respective metabolites.  相似文献   
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In this study, the mitochondrial DNA diversity of six Spanish donkey breeds and two African donkey populations (one from Morocco and the other from Zimbabwe) was analysed. A total of 79 animals were sequenced for 313 bp of the cytochrome b gene, and 91 individuals for 383 bp of the D‐loop region or control‐region. Sequence comparisons and phylogenetic analyses of both Spanish and African populations revealed low diversity. Only six and seven haplotypes respectively were found in cytochrome b and the D‐loop region. Relatively low nucleotide diversity (π) values were detected in these populations. The π values, from the D‐loop region, ranged from 0.0006 to 0.0169 for the Catalana and Andaluza breeds, respectively. The obtained results seem to confirm the existence of two divergent maternal lineages of African origin (Equus asinus africanus and E. a. somaliensis). In this paper the genetic relationships between these breeds are analysed and compared with those obtained in other European populations. Also, the data on the genetic relationships between the populations, obtained from nuclear DNA (microsatellites) and mitochondrial DNA (cytochrome b and D‐loop region) is argued and interpreted.  相似文献   
44.
The Catalonian donkey is one of the most endangered donkey breeds in the world. At present, five main subpopulations exist: AFRAC, which consists of many genetically connected Catalonian localities; Berga, which consists of a single herd located also in Catalunya but under private management; and three minor non‐Catalonian subpopulations (Huesca, Sevilla and Toledo). In this study, we analysed the pedigree information of the Catalonian donkey herdbook to assess the genetic diversity and population structure of the breed. We found that the Catalonian donkey has suffered an important loss of genetic diversity and moderate to high increases of inbreeding because of the abuse of a few individuals in matings. This scenario is mainly characterized by the fact that both the effective number of founders and ancestors for the whole population was 70.6 and 27, respectively, while the equivalent number of founders was 146.5 and the number of ancestors explaining overall genetic variability was 93. In addition, only 14% of animals born between the 1960s and 1970s were significantly represented in the pedigree. Our results also show that subpopulations where breeders exchanged reproductive individuals had low levels of inbreeding and average relatedness. One subpopulation, Berga, was reproductively isolated and showed high levels of inbreeding (F = 7.22%), with average relatedness (AR = 6.61%) playing an important role in increasing the values of these coefficients in the whole pedigree. Using genealogical F‐statistics we have found little evidence of population structuring (FST = 0.0083) with major genetic differences among non‐Catalonian subpopulations.  相似文献   
45.
A 5-year-old National Hunt Thoroughbred mare presented with sudden onset left hindlimb lameness after race training on the gallops. Clinical examination revealed a marked painful reaction over the proximal metatarsal region but no other obvious abnormalities were detected. Survey radiographs at the yard did not reveal any abnormalities. Nuclear scintigraphic examination 3 days after injury revealed focal marked increased radiopharmaceutical uptake in the proximal metatarsal region. Subsequent radiography revealed an incomplete, articular fracture of the proximal left third metatarsal bone. Repair of the fracture using 3 × 4.5 mm cortical screws placed in lag fashion was performed under standing sedation following perineural analgesia. Follow-up radiographs demonstrated progressive healing of the fracture. The mare returned to race training 8 months after the fracture was repaired and raced successfully 12 months post injury.  相似文献   
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