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71.
Eliecer Eidelman Aubrey Chosack Kurt A. Rosenzweig 《American journal of physical anthropology》1973,39(1):129-133
The teeth of 10,371 male and 11,013 female Israel Jews were examined. Prevalence of all hypodontia was 4.60% with no significant difference between the sexes; 2.11% lacked upper lateral incisors, the females having a significantly higher prevalence than males. Second premolars were missing in 1.87% of the population, with no significant differences between the sexes. Missing lower incisors was diagnosed in 0.68% of the children, with a higher prevalence in males. Prevalence of missing lower incisors was similar in the Ashkenazi and in the non-Ashkenazi. The teeth most frequently missing in descending order were the upper lateral incisors and the lower second premolars. 相似文献
72.
Summary Bean and marigold plants were grown to maturity under several kinds of fluorescent lamps to evaluate the effects of spectral differences on development and reproduction. Six kinds of lamps were tested including five lamps that were used in closely related experiments on tomato seedling growth (Thomas and Dunn, 1967). Evaluation was by fresh- and dry-weight yields of immature and mature pods, and of vegetative tops of plants for bean; and by flowering and fresh-and dry-weight yields for marigold.Bean plants grown under two experimental lamps, Com I and IR III produced significantly higher fresh- and dry-weight yields of both mature and total pods than under Warm-white lamps. This effect could be attributed largely to the considerable energy emitted by the experimental lamps in the red and far-red, as compared to a larger emission in the green and blue for the Warm-white lamps. The differences in the yields for immature pods and vegetative portions of the mature tops were not significant.In a comparison of the effects of three experimental lamps with those of three commercial lamps on growth response of bean plants, the yields were in general higher for the experimental lamps, except for immature pods. The yields of vegetative tops were significantly greater for the 78/22 lamp over the yields for all other lamps. The larger proportion of red and far-red light emitted by the experimental lamps is again the probable cause of the higher yields with these lamps.Two sets of experiments on growth and flowering of marigold under various experimental and commercial lamps were largely inconclusive although there was some indication of beneficial effects by the experimental lamps.In general, the results with bean agree with those for tomato (Thomas and Dunn, 1967), in that best growth was obtained with a lamp high in red light emission, a moderate amount in the far-red, and very little in the blue part of the spectrum.This research was submitted by the senior author in partial fulfillment of the requirements for the M.S. degree in Botany at the University of New Hampshire.Published with the approval of the director of the New Hampshire Agricultural Experiment Station as Scientific Contribution No. 398. This study was part of the Northeast Regional Project, NE-35, Analysis of Northeastern Climatic Variables and Their Relationships to Plant Response. 相似文献
73.
Recognition that breast cancer is a heterogeneous disease in which each patient's tumor has specific characteristics has led to a search for biomarkers and combinations of markers (signatures) to improve the diagnosis, prognostic classification and prediction of therapeutic benefit versus toxicity for individual tumors and patients. Many microRNAs (miRNAs) are aberrantly expressed in cancer and seem to influence tumor behavior and progression. miRNAs have great potential to evolve into effective biomarkers in the clinic because of their extreme stability and ease of detection. However, there are several major technical challenges as well as numerous discrepancies among currently reported miRNA signatures. In this review, we discuss the use of miRNA signatures for breast cancer treatment and discuss the challenges in the field. 相似文献
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Aubrey Leacock 《BMJ (Clinical research ed.)》1952,1(4772):1347-1349
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Brandon A. Fricker Ashley W. Seifert Aubrey M. Kelly 《Ethology : formerly Zeitschrift fur Tierpsychologie》2022,128(1):26-40
While there are many species that are commonly used for the study of mammalian social behavior, there remains a need for lab-suitable organisms that are appropriate for examining sociality specifically in non-reproductive contexts (i.e., social behavior not in the context of mating or parenting). The spiny mouse, Acomys cahirinus, is a cooperatively breeding rodent that lives in large groups and is a species that holds great potential for studying a wide range of social behaviors in reproductive and non-reproductive contexts. Here, we characterize the basic social behaviors in male and female A. cahirinus to obtain a foundation for future study. We tested adult A. cahirinus in social approach, social preference, social interaction, social recognition, and group size preference paradigms. Regardless of sex, novelty, or familiarity, we found that both males and females rapidly approach conspecifics demonstrating high social boldness. Additionally, both sexes are significantly more prosocial than aggressive when freely interacting with conspecifics. However, we observed effects of sex on social preferences, such that males exhibit a preference to affiliate with same-sex conspecifics, whereas females exhibit a preference for affiliating with opposite-sex conspecifics. We discuss how this preference may relate to the cooperative breeding system of spiny mice. Lastly, both sexes show a robust preference for affiliating with large over small groups, indicating they may be an ideal species for the study of mammalian gregariousness. These data lay a basic foundation for future studies that seek to assess complex group dynamics and the mechanisms underlying reproductive and non-reproductive social behaviors in a highly social mammal. 相似文献