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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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R M Sweeting B A McKeown 《Comparative biochemistry and physiology. A, Comparative physiology》1987,88(1):147-151
1. Effects of growth hormone (GH) were examined on short-term aspects of seawater adaptation in coho salmon smolts. 2. Injection of somatostatin (SRIF) immediately prior to seawater entry suppressed plasma GH levels, but did not have any significant effects at 6 or 12 hr on hematocrits, plasma glucose or plasma Na+ levels. 3. Plasma GH levels increased 250% within 36 hr after seawater exposure. 4. Plasma glucose levels, in contrast, were significantly lower in the seawater fish after 36 hr post-exposure. 5. Plasma Na+ levels increased to 190 mEq/1 by 24 hr but subsequently returned to freshwater levels while hematocrits showed no significant changes over the 72 hr of exposure. 6. The significance of these results is discussed in terms of successful seawater adaptation in coho salmon. 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
7.
Theodore Page Charles Sherwood James D. Connor Thomas Tarnowski 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,675(2):342
A fast, simple, and cost-effective HPLC method for the quantitation of the antiviral drug ganciclovir is described. The serum samples are extracted with perchloric acid and neutralized with potassium phosphate buffer, and urine samples are diluted with distilled water. A reversed-phase column with isocratic elution by 15 mM potassium phosphate buffer (pH 2.5) containing 0.25% acetonitrile is used to separate ganciclovir; quantitation is by UV absorbance at 254 nm. Total turnaround time is 22 min; more than 3000 samples can be run on a single column without loss of peak quality. The limit of quantitation is 0.05 μg/ml. Recoveries varied from 91 to 10% with coefficients of variation ranging from 0.387 to 7.95%. 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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Douglas G. Gilmour Walter M. Collins Tom L. Fredericksen Willard E. Urban Jr. Paul F. Ward Nancy L. DiFronzo 《Immunogenetics》1986,23(1):1-6
Chickens of Regional Poultry Research Laboratory (RPRL) inbred line 63 regress sarcomas induced by Bryan high-titer Rous sarcoma virus to a greater extent than chickens of line RPRL 100, although these lines are identical for the major histocompatibility B complex. They differ, however, at three independent autosomal loci: Ly-4 and Th-1 determine the surface alloantigens of partly overlapping subsets of T lymphocytes, and Bu-1 determines a surface alloantigen of B lymphocytes. The association of genotypes at these loci with quantitative variation in their ability to regress Rous sarcomas was tested in segregating F4 generation progeny derived from crosses of lines 100 and 63. The Ly-4 and Bu-1 genotypes showed association with Rous sarcoma regression, but the Th-1 genotype did not. Chickens of the Ly-4
a/Ly-4
a, Bu-1
b/Bu-1
b and Ly-4
b/Ly-4
b, Bu-1
a/Bu-1
a genotypes had a significantly higher regressor ability than the other two double homozygous genotypes. These results indicate that higher regression is associated with (1) interaction between the Ly-4 and Bu-1 loci, and (2) complementation between either the line 6 Ly-4
a allele and the line 100 Bu-1
b allele, or the line 100 Ly-4
b allele and the line 6 Bu-1
a allele. 相似文献