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1.
Landscape Ecology - Forest landscapes at the boreal–temperate ecotone have been extensively altered. Reducing the gap between current and presettlement forest conditions through...  相似文献   
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Clinical, radiological and ultrasonographic findings from 22 cats with gastrointestinal lymphosarcoma were reviewed. The most common clinical findings were anorexia, weight loss, vomiting, lethargy, depression, fever, anemia and a palpable abdominal mass. Abdominal radiographs of 12 cats revealed a mass associated with the gastrointestinal tract and/or mesentery, and decreased serosal detail, suggestive of peritoneal effusion. The most common ultrasonographic finding was transmural gastric or intestinal thickening associated with loss of normal wall layering, reduced wall echogenicity and localized hypomotility. As is noted in people, other patterns such as transmural-segmental, transmural-nodular, transmural-bulky and mucosal infiltration were represented. In 3 cats, mesenteric lymph-adenopathy was responsible for most of the mass-effect. Fine-needle aspiration biopsy, automated microcore biopsy, endoscopic biopsy or necropsy confirmed the diagnosis of lymphosarcoma in all cats. Chemotherapy was instituted in 19 cats. Only 6 cats had a complete response to treatment. The results of this study indicate that ultrasonography is a valuable tool for the diagnosis of feline alimentary lymphosarcoma and that biopsies can be obtained under ultrasonographic guidance.  相似文献   
3.
The purpose of this study was to evaluate the usefulness of ultrasound-guided fine-needle aspiration biopsy and core biopsy in the diagnosis of infiltrative gastrointestinal diseases. Six dogs and seven cats with clinical signs of gastrointestinal disease underwent ultrasonography and intestinal lesions were identified. One or more ultrasound-guided fine-needle aspiration biopsy and/or core biopsy procedures were performed in each patient. Each patient also underwent one of the following additional procedures for comparison of results: 1) surgery (n=4), 2) endoscopy (n=2), 3) post mortem exam (n=3), and, 4) for lymphoma diagnosed with ultrasound-guided procedures, response to chemotherapy (n=4). Correct diagnoses were obtained in nine of the 13 patients, incorrect diagnoses in two of the 13 patients, and inconclusive diagnoses in two of the thirteen patients. Of the 16 total ultrasound-guided procedures performed, ten were confirmed as correct, three as incorrect, and three were non-diagnostic. Intestinal lesions with bowel wall thickness greater than 2.0 cm had a higher percentage of correct diagnoses than lesions of lesser wall thickness. Gastric lesions had a higher percentage of correct diagnoses than small and large intestinal lesions. Malignant lesions had a higher percentage of correct diagnoses than benign lesions. There were no complications. Ultrasound-guided gastrointestinal fine-needle aspiration biopsy and core biopsy appears to be a safe, accurate, and rapid procedure for use in the diagnosis of infiltrative gastrointestinal disease.  相似文献   
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Fusarium circinatum is the causal agent of pitch canker, a destructive disease that threatens natural and planted pine forests around the world. Although pitch canker has caused problems in Spain and Portugal, concerning Europe as a whole, the fungus is not established across the pine distribution area. Its dispersion by wind and/or insect vectors could nevertheless play a role in the colonization of currently uninfected stands. It is therefore crucial to develop monitoring tools for its detection. To this end, we assessed the molecular detection of the pathogen in environmental samples of bark beetles and passive spore traps, collected in two infected Pinus radiata plantations in Basque country, Spain. The spread pattern of F. circinatum was assessed by an experimental design that included insect and spore traps installed at the centre, at the edge and outside the plots. Our results showed that F. circinatum was detected in both types of samples, at almost all collection dates. In both type of samples, positive detections were mainly found at the centre of the plots, a lower proportion at the edge, and very few outside. This suggests that long‐distance dispersion of Fusarium circinatum does not rely on wind spore dispersal neither on insect flight. Our study also shows that molecular methods are a powerful tool to monitor the pathogen in environmental samples.  相似文献   
6.
This study investigates how age at first maturity of two tropical amphidromous species Sicyopterus lagocephalus (Pallas, 1770) and Cotylopus acutipinnis (Guichenot, 1863) varies in relation to their larval and juvenile life history. Reproductive stage was estimated based on histological observation of ovaries of more than 200 females of each species caught monthly over 1 year. The age of fish was estimated by interpreting the daily increments deposited on otoliths during the oceanic larval phase, and the juvenile phase in the river. The age at first maturity was approximately 9 months for S. lagocephalus and 7 months for C. acutipinnis, corresponding to approximately 70–130 and 90–130 days after they returned to freshwater respectively. For both species, the time spent in freshwater before maturity was significantly influenced by the duration of the pelagic larval stage at sea (PLD) and the season of return in freshwater. Individuals with a long PLD, or returning in freshwater during the warmer season, maturated faster once in freshwater. This reproductive advantage may minimise the risk of extirpation due to catastrophic events at each generation and thus probably benefits amphidromous species living in very unpredictable tropical rivers.  相似文献   
7.
The mutation T3811 → G3811 (TG3811) discovered in the myostatin gene of the Blonde d’Aquitaine breed is suspected of contributing to the outstanding muscularity of this breed. An experiment was designed to estimate the effect of this mutation in an F2 and back-cross Blonde d’Aquitaine × Holstein population. By genotyping all known mutations in the myostatin gene, it was ensured that the TG3811 mutation was indeed the only known mutation segregating in this population. Fifty-six calves (43 F2, 13 back-cross) were intensively fattened and slaughtered at 24.0 ± 1.4 wk of age. The effects of the mutation were estimated by comparing the calves with the [T/T] (n = 18), [T/G] (n = 30), and [G/G] (n = 8) genotypes. Highly significant substitution effects (P < 0.001), above + 1.2 phenotypic SD, were shown on carcass yield and muscularity scores. Birth weight (P < 0.001) was positively affected by the mutation (+0.8 SD) but not growth rate (P = 0.97), while carcass length (P = 0.03), and fatness (P ≤ 0.03) were negatively affected (–0.5 to –0.7 SD). The characteristics of the Triceps brachii muscle were affected by the mutation (P < 0.001), with lower ICDH activity (oxidative) and a higher proportion of myosin type 2X muscle fibers (fast twitch). The effects of the TG3811 mutation were similar to those of other known myostatin mutations, although the Blonde d’Aquitaine animals, which are predominantly [G/G] homozygous, do not exhibit extreme double muscling.  相似文献   
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Hair follicle neoplasms occur in many different species, including humans. In domestic animals, they are most common in dogs. Most hair follicle tumors are benign, but malignant neoplasms can also occur. To diagnose hair follicle neoplasms, a thorough knowledge of follicular anatomy is important, given that follicular tumors are classified according to the differentiation pattern seen in the corresponding part of the normal hair follicle. This review focuses on the key diagnostic features of hair follicle tumors and follicular cysts in dogs and cats.  相似文献   
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