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Inhibitors of cyclin‐dependent kinases, as roscovitine, have been used to prevent the spontaneous resumption of meiosis in vitro and to improve the oocyte developmental competence. In this study, the interference of oil overlay on the reversible arrest capacity of roscovitine in sheep oocytes as well as its effects on cumulus expansion was evaluated. For this, cumulus‐oocyte complexes (COCs) were cultured for 20 h in TCM 199 with 10% foetal bovine serum (Control) containing 75 μm roscovitine (Rosco). Subsequently, they were in vitro matured (IVM) for further 18 h in inhibitor‐free medium with LH and FSH. The culture was performed in Petri dishes under mineral oil (+) or in 96 well plates without oil overlay (?) at 38.5°C and 5% CO2. At 20 and 38 h, the cumulus expansion and nuclear maturation were evaluated under stereomicroscope and by Hoechst 33342 staining, respectively. No group presented cumulus expansion at 20 h. After additional culture with gonadotrophins, a significant rate of COCs from both Control groups (+/?) exhibited total expansion while in both Rosco groups (+/?) the partial expansion prevailed. Among the oocytes treated with roscovitine, 65.2% were kept at GV in the absence of oil overlay while 40.6% of them reached MII under oil cover (p < 0.05). This meiotic arrest was reversible, and proper meiosis progression also occurred in the Control groups (+/?). So, the culture system without oil overlay improved the meiotic inhibition promoted by roscovitine without affecting the cumulus expansion rate or the subsequent meiosis progression.  相似文献   
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Formation of a Schiff base between the ethylamine residue of serotonin and an appropriate carbonyl residue at the receptor site may be among the forces holding serotonin onto the receptor. Reduction of this imine may provide a means of permanently labeling receptors as a preliminary to their isolation.  相似文献   
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An 8-year-old male Labrador retriever presented with a rear limb lameness cased by an osteolytic lesion of the left acetabulum and femoral head and neck. Initial bone biopsy study was nondiagnostic. Histopathologic study and culture of the subsequently excised femoral head and neck revealed a Staphyloccocus intermedial arthritis and osteomyelitis. Neoplash was ruled out on the basis of histopathologic analysis.  相似文献   
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OBJECTIVES: To develop and validate a short food-frequency questionnaire to assess habitual dietary salt intake in South Africans and to allow classification of individuals according to intakes above or below the maximum recommended intake of 6 g salt day-1. DESIGN: Cross-sectional validation study in 324 conveniently sampled men and women. METHODS: Repeated 24-hour urinary Na values and 24-hour dietary recalls were obtained on three occasions. Food items consumed by >5% of the sample and which contributed > or =50 mg Na serving-1 were included in the questionnaire in 42 categories. A scoring system was devised, based on Na content of one index food per category and frequency of consumption. RESULTS: Positive correlations were found between Na content of 35 of the 42 food categories in the questionnaire and total Na intake, calculated from 24-hour recall data. Total Na content of the questionnaire was associated with Na estimations from 24-hour recall data (r = 0.750; P < 0.0001; n = 328) and urinary Na (r = 0.152; P = 0.0105; n = 284). Urinary Na was higher for subjects in tertile 3 than tertile 1 of questionnaire Na content (P < 0.05). Questionnaire Na content of <2400 and > or =2400 mg day-1 equated to a reference cut-off score of 48 and corresponded to mean (standard deviation) urinary Na values of 145 (68) and 176 (99) mmol day-1, respectively (P < 0.05). Sensitivity and specificity against urinary Na > or =100 and <100 mmol day-1 was 12.4% and 93.9%, respectively. CONCLUSION: A 42-item food-frequency questionnaire has been shown to have content-, construct- and criterion-related validity, as well as internal consistency, with regard to categorising individuals according to their habitual salt intake; however, the devised scoring system needs to show improved sensitivity.  相似文献   
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Primary intraosseous fibrosarcoma in a cat   总被引:1,自引:0,他引:1  
A primary intraosseous fibrosarcoma was diagnosed in a 1.5-year-old cat. Clinical signs included nonweight-bearing lameness of the right forelimb and signs of pain on palpation of the right elbow. Radiography of the right elbow revealed a well-circumscribed osteolytic lesion of the olecranon. The right fore-limb was amputated, and histologic examination revealed tumor invasion into local veins and metastasis to the axillary lymph nodes. The cat had no signs of tumor redevelopment or pulmonary metastatic disease one year after amputation.  相似文献   
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Background  

Terabyte-scale collections of string-encoded data are expected from consortia efforts such as the Human Microbiome Project . Intra- and inter-project data similarity searches are enabled by rapid k-mer matching strategies. Software applications for sequence database partitioning, guide tree estimation, molecular classification and alignment acceleration have benefited from embedded k-mer searches as sub-routines. However, a rapid, general-purpose, open-source, flexible, stand-alone k-mer tool has not been available.  相似文献   
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