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71.
Haplogroup X represents approximately 3% of all modern Native North American mitochondrial lineages. Using RFLP and hypervariable segment I (HVSI) sequence analyses, we identified a prehistoric individual radiocarbon dated to 1,340 +/- 40 years BP that is a member of haplogroup X, found near the Columbia River in Vantage, Washington. The presence of haplogroup X in prehistoric North America, along with recent findings of haplogroup X in southern Siberians, confirms the hypothesis that haplogroup X is a founding lineage. 相似文献
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73.
Manson SM 《Culture, medicine and psychiatry》2003,27(4):395-408
The August 2001 issuance of Mental Health: Culture, Race, and Ethnicity--A Supplement to Mental Health: A Report of the Surgeon General, represents a landmark in the dialogue--political and scientific--regarding health disparities in the United States. This paper offers a critical appraisal of the process and structure of generating these reports, paying particular attention to issues that marked serious epistemological tensions among the participants. These issues revolved around the relative emphasis placed on (1) mental illness and mental health; (2) risk, etiology, and treatment versus prevention and promotion; (3) large-scale, population-based surveys and randomized clinical trials as the standard bearers of scientific evidence; (4) variation related to gender, social class, and culture; (5) ethnicity and culture as dispositional variables or individual glosses as opposed to dynamic, collective phenomena; and (6) the historical forces that shaped the contemporary context for much of this discussion. It describes the sometimes subtle, other times stark differences in assumptions and experience that sprang from disciplinary orientations, investigative methods, institutional affiliations, and personal histories and agendas. 相似文献
74.
American Association of Tissue Banks: A Historical Reflection Upon Entering the 21st Century 总被引:1,自引:0,他引:1
Joyce MJ 《Cell and tissue banking》2000,1(1):5-8
The American Association of Tissue Banks (AATB) is a scientific, not-for-profit, peer-group organization founded in 1976 to facilitate the provision of transplantable tissues of uniform high quality in quantities sufficient to meet national needs. The Association was created well before there was governmental oversight of tissue banking. The organization consists of individuals involved in tissue banking, medical users, and scientists in the field. Current structure consists of a 13-member Board of Governors with specific subgroups including Musculoskeletal, Reproductive, Skin, Tissue Bank Councils and Council of Accredited Tissue Banks. A historical review shows the evolution from development of guidelines to publication of standards, and from an inspection conducted by peers to one conducted by an independent, trained professional inspector. Association growth and historical accomplishments are highlighted. 相似文献
75.
The American Anthropological Association's investigation of the charges in Darkness in El Dorado (Tierney 2000) found that the late James Neel and Napoleon Chagnon harmed the Yanomami in the course of their research in Venezuela and Brazil, and that Chagnon had violated the ethics code of the association. The association's inquiry contravened its own policy prohibiting ethics adjudications and was structured not by the standards of an objective investigation but by aspects of contemporary anthropology. Moralized approaches to information and postmodern rejection of objectivity mark the language and methods of the inquiry. The investigating task force did not observe reasonable standards of evidence, the targets of the investigation were not represented, and task force members were compromised by conflicts of interest. The investigation and its collateral activities reflect a culture of accusation and an anthropology uncertain of its ethical or scientific stature. 相似文献
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77.
Matt Shinderman 《Ecology and evolution》2015,5(17):3666-3676
In 2010, the American pika (Ochotona princeps fenisex) was denied federal protection based on limited evidence of persistence in low‐elevation environments. Studies in nonalpine areas have been limited to relatively few environments, and it is unclear whether patterns observed elsewhere (e.g., Bodie, CA) represent other nonalpine habitats. This study was designed to establish pika presence in a new location, determine distribution within the surveyed area, and evaluate influences of elevation, vegetation, lava complexity, and distance to habitat edge on pika site occupancy. In 2011 and 2012, we conducted surveys for American pika on four distinct subalpine lava flows of Newberry National Volcanic Monument, Oregon, USA. Field surveys were conducted at predetermined locations within lava flows via silent observation and active searching for pika sign. Site habitat characteristics were included as predictors of occupancy in multinomial regression models. Above and belowground temperatures were recorded at a subsample of pika detection sites. Pika were detected in 26% (2011) and 19% (2012) of survey plots. Seventy‐four pika were detected outside survey plot boundaries. Lava complexity was the strongest predictor of pika occurrence, where pika were up to seven times more likely to occur in the most complicated lava formations. Pika were two times more likely to occur with increasing elevation, although they were found at all elevations in the study area. This study expands the known distribution of the species and provides additional evidence for persistence in nonalpine habitats. Results partially support the predictive occupancy model developed for pika at Craters of the Moon National Monument, another lava environment. Characteristics of the lava environment clearly influence pika site occupancy, but habitat variables reported as important in other studies were inconclusive here. Further work is needed to gain a better understanding of the species’ current distribution and ability to persist under future climate conditions. 相似文献
78.
79.
Deng-Liang Wang Yan-Ling Song Zhi Zhu Xi-Lan Li Yuan Zou Hai-Tao Yang Jiang-Jie Wang Pei-Sen Yao Ru-Jun Pan Chaoyong James Yang De-Zhi Kang 《Biochemical and biophysical research communications》2014
Epidermal growth factor receptor (EGFR/HER1/c-ErbB1), is overexpressed in many solid cancers, such as epidermoid carcinomas, malignant gliomas, etc. EGFR plays roles in proliferation, invasion, angiogenesis and metastasis of malignant cancer cells and is the ideal antigen for clinical applications in cancer detection, imaging and therapy. Aptamers, the output of the systematic evolution of ligands by exponential enrichment (SELEX), are DNA/RNA oligonucleotides which can bind protein and other substances with specificity. RNA aptamers are undesirable due to their instability and high cost of production. Conversely, DNA aptamers have aroused researcher’s attention because they are easily synthesized, stable, selective, have high binding affinity and are cost-effective to produce. In this study, we have successfully identified DNA aptamers with high binding affinity and selectivity to EGFR. The aptamer named TuTu22 with Kd 56 ± 7.3 nM was chosen from the identified DNA aptamers for further study. Flow cytometry analysis results indicated that the TuTu22 aptamer was able to specifically recognize a variety of cancer cells expressing EGFR but did not bind to the EGFR-negative cells. With all of the aforementioned advantages, the DNA aptamers reported here against cancer biomarker EGFR will facilitate the development of novel targeted cancer detection, imaging and therapy. 相似文献
80.
A quantitative real-time PCR method for in planta monitoring of Phytophthora infestans growth 总被引:1,自引:0,他引:1
Llorente B Bravo-Almonacid F Cvitanich C Orlowska E Torres HN Flawiá MM Alonso GD 《Letters in applied microbiology》2010,51(6):603-610
Aim: To develop a real‐time PCR‐based strategy for the detection of Paenibacillus larvae vegetative cells and spores to improve the diagnosis and the screening of American foulbrood (AFB), the most harmful pathology of honeybee brood. Methods and Results: A real‐time PCR that allowed selective identification and quantification of P. larvae 16S rRNA sequence was developed. Using standard samples quantified by flow cytometry, detection limits of 37·5 vegetative cells ml?1 and 10 spores ml?1 were determined. Compared to spread plate method, this real‐time PCR‐based strategy allowed, in only 2 h, the detection of P. larvae in contaminated honeys. No false‐positive results were obtained. Moreover, its detection limit was 100 times lower than that of the culture method (2 vs 200 spores g?1 of honey). Conclusion: A rapid, selective, with low detection limit, sensitive and specific method to detect and quantify vegetative cells and spores of P. larvae is now available. Significance and Impact of Study: In addition to honey samples, this real‐time PCR‐based strategy may be also applied to confirm AFB diagnosis in honeybee brood and to screen other apiary supplies and products (bees, pollen, wax), thus broadening the control of AFB spreading. 相似文献