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A group of captive chimpanzees, consisting of one adult male and three mother/infant pairs, was systematically observed over a 15-month period. Over 200 hr of data were collected, using both sequential and time sampling techniques, and compared to the available data on wild chimps. Unlike many captive groups, most behavior patterns were remarkably similar, both qualitatively and quantitatively, to that of wild chimpanzees including: play, grooming, infant sexual development, tool use, food sharing, prosocial partner preferences, and aggressive displays. 相似文献
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S. P. Kharitonov D. E. Nowak A. I. Nowak N. A. Egorova S. A. Korkina D. V. Osipov O. V. Natal’skaya 《Biology Bulletin》2009,36(5):469-478
Red-breasted goose colonies have been studied near Medusa Bay (73°21′N, 80°32′E), on the northwestern Taimyr Peninsula, and
along the Agapa River (70°11′N, 86°15′E) down to its mouth (71°26′N, 89° 13′E), in the central Taimyr Peninsula. Red-breasted
geese nesting near peregrine falcons are protected by the falcons from arctic foxes; however, they are sometimes attacked
by the falcons themselves. In the colonies near peregrine falcon nests, the vast majority of goose nests were situated no
farther than 100 m from the falcon nest. When food is abundant, falcons protect a larger area around their nest. The distance
between the falcon nest and the surrounding goose nests is inversely related to the falcon’s activity. In years of higher
falcon activity, falcons prevent red-breasted geese from nesting as close to their nest as in years of lower falcon activity.
Additional stimuli are required for red-breasted geese to form colonies near rough-legged buzzard nests. The distance between
snowy owl nests and red-breasted goose nests was smaller when arctic foxes were abundant than when they were scarce. 相似文献
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Nancy Burton Wurster George Lust 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,800(1):52-58
The content and the biosynthesis of fibronectin was examined in disease-free articular cartilage and in articular cartilage from osteoarthritic canine joints. Fibronectin content was increased in extracts of cartilage from osteoarthritic joints. Incubation of cartilage in vitro with [3H]phenylalanine and subsequent isolation of [3H]fibronectin from a gelatin affinity column and characterization by SDS-polyacrylamide gel electrophoresis and by immunoprecipitation indicated that disease-free and osteoarthritic cartilage explants synthesized fibronectin. About 50% of the [3H]fibronectin was recovered in the incubation medium. The osteoarthritic cartilage synthesized and accumulated up to 5-fold more [3H]fibronectin than disease-free cartilage. 相似文献
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Chicken gizzard tropomyosin was digested with carboxypeptidase A at the weight ratios of enzyme to substrate 1:200 and 1:50. Removal of about 16 C-terminal amino acid residues per tropomyosin molecule, at lower enzyme concentration, caused reversion of the effect on skeletal actomyosin ATPase activity from activating to inhibiting without an influence on polymerizability and actin-binding ability. Removal of about 26 C-terminal amino acid residues per molecule, at higher enzyme concentration, resulted in loss of polymerizability and actin binding ability. Digestion of gizzard tropomyosin with carboxypeptidase A has no dramatic effect on its binding to troponin T. The results show that not only the existence of head-to-tail overlapping regions but also their length is important for the functional properties of chicken gizzard tropomyosin. 相似文献
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Emily Olfson Catherine E. Cottrell Nicholas O. Davidson Christina A. Gurnett Jonathan W. Heusel Nathan O. Stitziel Li-Shiun Chen Sarah Hartz Rakesh Nagarajan Nancy L. Saccone Laura J. Bierut 《PloS one》2015,10(9)
The American College of Medical Genetics and Genomics (ACMG) recommends that clinical sequencing laboratories return secondary findings in 56 genes associated with medically actionable conditions. Our goal was to apply a systematic, stringent approach consistent with clinical standards to estimate the prevalence of pathogenic variants associated with such conditions using a diverse sequencing reference sample. Candidate variants in the 56 ACMG genes were selected from Phase 1 of the 1000 Genomes dataset, which contains sequencing information on 1,092 unrelated individuals from across the world. These variants were filtered using the Human Gene Mutation Database (HGMD) Professional version and defined parameters, appraised through literature review, and examined by a clinical laboratory specialist and expert physician. Over 70,000 genetic variants were extracted from the 56 genes, and filtering identified 237 variants annotated as disease causing by HGMD Professional. Literature review and expert evaluation determined that 7 of these variants were pathogenic or likely pathogenic. Furthermore, 5 additional truncating variants not listed as disease causing in HGMD Professional were identified as likely pathogenic. These 12 secondary findings are associated with diseases that could inform medical follow-up, including cancer predisposition syndromes, cardiac conditions, and familial hypercholesterolemia. The majority of the identified medically actionable findings were in individuals from the European (5/379) and Americas (4/181) ancestry groups, with fewer findings in Asian (2/286) and African (1/246) ancestry groups. Our results suggest that medically relevant secondary findings can be identified in approximately 1% (12/1092) of individuals in a diverse reference sample. As clinical sequencing laboratories continue to implement the ACMG recommendations, our results highlight that at least a small number of potentially important secondary findings can be selected for return. Our results also confirm that understudied populations will not reap proportionate benefits of genomic medicine, highlighting the need for continued research efforts on genetic diseases in these populations. 相似文献
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