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1.
Metastasis is a defining feature of malignant tumors and is the most common cause of cancer-related death, yet the genetics of metastasis are poorly understood. We used exome capture coupled with massively parallel sequencing to search for metastasis-related mutations in highly metastatic uveal melanomas of the eye. Inactivating somatic mutations were identified in the gene encoding BRCA1-associated protein 1 (BAP1) on chromosome 3p21.1 in 26 of 31 (84%) metastasizing tumors, including 15 mutations causing premature protein termination and 5 affecting its ubiquitin carboxyl-terminal hydrolase domain. One tumor harbored a frameshift mutation that was germline in origin, thus representing a susceptibility allele. These findings implicate loss of BAP1 in uveal melanoma metastasis and suggest that the BAP1 pathway may be a valuable therapeutic target.  相似文献   
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Stages of gonadal development, in association with plasma concentrations of the sex steroids 17β‐estradiol (E2), progesterone (P4), testosterone (T), and 11‐ketotestosterone (11‐KT), were investigated for a single time point during a natural breeding season in 7‐yr‐old Siberian sturgeon, Acipenser baeri Brandt, exposed lifelong to a warmwater environment. Among females, examination of gonadal tissue showed variation in ovarian stage, with 12.5, 47.5, 22.5, and 17.5% of females found at Stages 2 (previtellogenic), 3 (early vitellogenic), 4 (mid‐vitellogenic), and 5 (migratory nucleus), respectively. Although patterns varied among the hormones, plasma concentrations of E2, T, and 11‐KT became increasingly elevated in females as maturation progressed. On the basis of histological criteria, males were classified as either premeiotic (quiescent) or meiotic and 50% of the males sampled were found at each stage. Significant elevations in circulating concentrations of plasma E2 and T were observed in meiotic versus premeiotic males, and there was a rise in plasma 11‐KT concentration that approached significance (P = 0.056).  相似文献   
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A method was developed for the analysis of salmon volatiles using solid-phase microextraction and gas chromatography-mass spectrometry. This method was used to monitor the volatiles of fresh king salmon (Oncorhynchus tshawytscha) stored in ambient air or in a 40:60 (v/v) mixture of CO2:N2 over time. The levels of several of the volatile compounds were found to change during storage, with some showing a clear difference between storage in air and storage in CO2:N2. Of these, several alcohols (cyclopentanol, Z-2-penten-1-ol, 1-penten-3-ol, and 1-octen-3-ol) and aldehydes (hexanal, octanal, E-2-pentenal, and E-2-hexenal) were identified as potential markers for salmon freshness. Several other volatiles (acetoin, ethyl benzene, propyl benzene, styrene, 3-methyl butanoic acid, and acetic acid) were identified as potential markers for salmon spoilage. A comparison of salmon harvested with and without the "rested harvesting" technique showed that E- and Z-isoeugenol levels were increased by the use of the isoeugenol based anesthetic. The use of the anesthetic did not affect the levels of any of the other compounds identified.  相似文献   
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A male, neutered cat was presented for lethargy, reluctance to walk, and mammary enlargement after recent treatment with megestrol acetate. Mammary fibroadenomatous hyperplasia was diagnosed on the basis of history, clinical signs, and histopathological findings. Pathogenesis, clinical signs, and treatment options for mammary fibroadenomatous hyperplasia attributed to megestrol acetate treatment are discussed.  相似文献   
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OBJECTIVE: To identify factors in dry diets associated with the occurrence of calcium oxalate (CaOx) uroliths in dogs. ANIMALS: 600 dogs with CaOx uroliths and 898 dogs without urinary tract diseases. PROCEDURE: Univariate and multivariate logistic regression were performed. RESULTS: Compared with diets with the highest concentrations of sodium, dry diets with the lowest concentrations of sodium, phosphorus, calcium, chloride, protein, magnesium, or potassium were linearly associated with increased risk of CaOx urolith formation. Significant nonlinear associations between increased occurrence of CaOx uroliths and urine acidifying potential and low moisture content were observed. Significant nonlinear associations between decreased occurrence of CaOx uroliths and carbohydrate and fiber contents were observed. A significant association between the occurrence of CaOx uroliths and dietary fat was not observed. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dry diets formulated to contain high concentrations of protein, calcium, phosphorus, magnesium, sodium, potassium, and chloride may minimize formation of CaOx uroliths. In addition, comparison of risk and protective factors of various diet ingredients fed to dogs with CaOx uroliths suggests that although similar findings were observed in canned and dry formulations, in general, greater risk is associated with dry formulations. However, before these hypotheses about dietary modifications are adopted by food manufacturers, they must be investigated by use of appropriately designed clinical studies of dogs with CaOx urolithiasis.  相似文献   
6.
OBJECTIVE: To identify dietary factors in commercially available canned foods associated with the development of calcium oxalate (CaOx) uroliths in dogs. ANIMALS: 117 dogs with CaOx uroliths and 174 dogs without urinary tract disease. PROCEDURE: Case dogs were those that developed CaOx uroliths submitted to the Minnesota Urolith Center for quantitative analysis between 1990 and 1992 while fed a commercially available canned diet. Control dogs were those without urinary tract disease evaluated at the same veterinary hospital just prior to or immediately after each case dog. A content-validated multiple-choice questionnaire was mailed to each owner of case and control dogs with the permission of the primary care veterinarian. Univariate and multivariate logistic regressions for each dietary component were performed to test the hypothesis that a given factor was associated with CaOx urolith formation. RESULTS: Canned foods with the highest amount of protein, fat, calcium, phosphorus, magnesium, sodium, potassium, chloride, or moisture were associated with a decreased risk of CaOx urolith formation, compared with diets with the lowest amounts. In contrast, canned diets with the highest amount of carbohydrate were associated with an increased risk of CaOx urolith formation. CONCLUSIONS AND CLINICAL RELEVANCE: Feeding canned diets formulated to contain high amounts of protein, fat, calcium, phosphorus, magnesium, sodium, potassium, chloride, and moisture and a low amount of carbohydrate may minimize the risk of CaOx urolith formation in dogs.  相似文献   
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Practical Molt Staging of Penaeus setiferus and Penaeus stylirostris   总被引:1,自引:0,他引:1  
Molt staging has many applications in penaeid aquaculture as a routine procedure. Using criteria developed for various crustaceans, a method of rapid molt staging was applied to Penaeus stylirostris and Penaeus setiferus adults. The most useful characters were the degree of epidermal retraction from the setal bases and epidermal retraction from the cuticle coupled with the development of new setae. The duration of the molt cycle of P. stylirostris was 11.5 ± 1.0 days ( N = 5) at 27–29 C. The early postmolt, late postmolt, intermolt, early premolt and late premolt stages were readily determined. For P. stylirostris , the duration of postmolt was 27% of the cycle; intermolt, 17%; and premolt, 56%. The length of the molt cycle of P. setiferus at 27–29 C was 13.6 ± 1.0 days ( N = 21) with postmolt occupying 22% of the cycle; intermolt, 19%; and premolt, 59%. Unilaterally eyestalk enucleated P. setiferus had a significantly shorter molt cycle than intact P. setiferus (11.7 ± 1.21 days vs. 13.6 ± 1.02 days, P < 0.05). There were no differences in molt cycle duration between the sexes, whether enucleated or intact ( P > 0.05). A series of illustrations identifies the key characteristics for determining stage of molt in these penaeids.  相似文献   
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