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81.
Tempo of trophic evolution and its impact on mammalian diversification   总被引:1,自引:0,他引:1  
Mammals are characterized by the complex adaptations of their dentition, which are an indication that diet has played a critical role in their evolutionary history. Although much attention has focused on diet and the adaptations of specific taxa, the role of diet in large-scale diversification patterns remains unresolved. Contradictory hypotheses have been proposed, making prediction of the expected relationship difficult. We show that net diversification rate (the cumulative effect of speciation and extinction), differs significantly among living mammals, depending upon trophic strategy. Herbivores diversify fastest, carnivores are intermediate, and omnivores are slowest. The tempo of transitions between the trophic strategies is also highly biased: the fastest rates occur into omnivory from herbivory and carnivory and the lowest transition rates are between herbivory and carnivory. Extant herbivore and carnivore diversity arose primarily through diversification within lineages, whereas omnivore diversity evolved by transitions into the strategy. The ability to specialize and subdivide the trophic niche allowed herbivores and carnivores to evolve greater diversity than omnivores.  相似文献   
82.
83.
目的 探寻医学影像存储与传输系统(PACS)集中打印中提升胶片信息识别率的有效方法.方法 分析各成像设备胶片布局中四角信息布局对识别率的影响因素;针对不同的影响因素,通过修改设备的四角信息格式、调整胶片格式、优化选片布局、修改放射信息系统存取号(RIS ACCESSION NUMBER)、引入正则表达式的正确性校验以及多次识别等优化方法识别胶片信息.结果 应用此方法对普放检查集中打印系统进行测试,在信息识别的准确性和有效性方面得到了显著的改进.结论 信息识别优化方法提高了胶片的信息识别率,为数字影像和通信标准(DICOM)电子胶片集中打印模式的实施提供了关键技术保障.  相似文献   
84.
The objective of this study was to describe the temperament dimension profiles assessed by the Temperament and Character Inventory (TCI) among young adults with the DSM-III-R personality disorder (PD). Our hypothesis was that PD clusters and separate PDs can be distinguished from one another by their specific temperament profiles. As a part of the 31-year follow-up survey of the prospective Northern Finland 1966 Birth Cohort, the cohort members living in the city of Oulu at the age of 31 years (n=1609) were invited to participate in a two-phase field study. The Structured Clinical Interview for DSM-III-R for PDs (SCID–II) was used as diagnostic instrument. The final study sample consisted of the 1311 subjects who had completed the Hopkins Symptom Check List-25 questionnaire for screening and had given a written informed consent. Of the 321 SCID interviewed subjects, 74 met the criteria for at least one PD and had completed the TCI. The mean TCI scores of subjects with PD and control subjects without PD (n=910) were compared. Low Novelty Seeking, high Harm Avoidance and low Reward Dependence characterized cluster A and C PDs. Subjects with a cluster B PD did not differ from controls, except for Novelty Seeking, which was high. The temperament dimensions could not distinguish different PDs very well, with the only exception of persons with obsessive–compulsive PD. PD clusters were associated with different profiles of temperament, lending some support for Cloninger's typology.  相似文献   
85.
The main aim of the present study was to investigate whether or not temperament dimensions are stable over time. Twenty-six patients (21 women and five men) filled in the Karolinska Scales of Personality (KSP) both at admission after a suicide attempt (index) and at follow-up 5 years later. KSP changes were significantly associated with low severity of psychiatric symptoms and no reported reattempts at follow up. There were significant changes of all five groups of KSP, most prominently in anxiety-related scales. At index, KSP scores did not differ between those who later would repeat a suicide attempt (repeaters) and not, but repeaters more often tended to have a personality disorder and their 24-h urinary cortisol tended to be lower. In this limited sample, repeaters seem to have a protracted high anxiety level as mirrored by high and stable KSP scores over time.  相似文献   
86.
ObjectiveTo study, whether temperament and character remain stable over time and whether they differ between patients with and without personality disorder (PD) and between patients with specific PDs.MethodsPatients with (n = 225) or without (n = 285) PD from Jorvi Bipolar Study, Vantaa Depression Study (VDS) and Vantaa Primary Care Depression Study were interviewed at baseline and at 18 months, and in the VDS also at 5 years. A general population comparison group (n = 264) was surveyed by mail.ResultsCompared with non-PD patients, PD patients scored lower on self-directedness and cooperativeness. Cluster B and C PDs associated with high Novelty Seeking and Harm Avoidance, respectively. In logistic regression models, sensitivity and specificity of Temperament and Character Inventory (TCI) dimensions for presence of any PD were 53% and 75%, and for specific PDs from 11% to 41% and from 92% to 100%, respectively. The 18-month test-retest correlations of TCI-R dimensions ranged from 0.58 to 0.82.ConclusionsMedium-term temporal stability of TCI in a clinical population appears good. Character scores differ markedly between PD and non-PD patients, whereas temperament scores differ only somewhat between the specific PDs. However, the TCI dimensions capture only a portion of the differences between PD and non-PD patients.  相似文献   
87.
马颖娴  李泳锋  李小蝶  蒙倩  崔亚君 《中草药》2019,50(16):3955-3961
目的对芫青科昆虫南方大斑蝥Mylabris phalerata和黄黑小斑蝥Mylabri scichorii中药材性状、微性状、粉末显微及微量升华结晶物显微特征进行研究,为其鉴定工作以及《中国药典》2020年版的制定工作提供科学依据。方法采用性状鉴别法、微性状鉴别法、常规显微鉴别法、偏振光显微鉴别法及微量升华法,对6批南方大斑蝥和4批黄黑小斑蝥进行系统的生药学研究。结果首次获取了南方大斑蝥和黄黑小斑蝥微性状鉴别特征(体长、触角、鞘翅、内翅等)、粉末显微鉴别特征(刚毛、体壁碎片、鞘翅碎片、内翅碎片、肌纤维、气管壁组织、未消化的植物组织)及其微量升华结晶物特征的全息彩色影像数据。结论微性状鉴别研究结果补充完善了传统宏观性状鉴别的细微构造特征,显微及微量升华鉴别研究结果可作为中药材及中成药中斑蝥鉴定的专属性标志物。  相似文献   
88.
Objective: Determine the extent to which pre-fitting acceptable noise level (ANL), with or without other predictors such as hearing-aid experience, can predict real-world hearing-aid outcomes at three and 12 months post-fitting. Design: ANLs were measured before hearing-aid fitting. Post-fitting outcome was assessed using the international outcome inventory for hearing aids (IOI-HA) and a hearing-aid use questionnaire. Models that predicted outcomes (successful vs. unsuccessful) were built using logistic regression and several machine learning algorithms, and were evaluated using the cross-validation technique. Study sample: A total of 132 adults with hearing impairment. Results: The prediction accuracy of the models ranged from 61% to 68% (IOI-HA) and from 55% to 61% (hearing-aid use questionnaire). The models performed more poorly in predicting 12-month than three-month outcomes. The ANL cutoff between successful and unsuccessful users was higher for experienced (~18 dB) than first-time hearing-aid users (~10 dB), indicating that most experienced users will be predicted as successful users regardless of their ANLs. Conclusions: Pre-fitting ANL is more useful in predicting short-term (three months) hearing-aid outcomes for first-time users, as measured by the IOI-HA. The prediction accuracy was lower than the accuracy reported by some previous research that used a cross-sectional design.  相似文献   
89.
Is suffering associated with melancholia and "madness" necessary for artistic creativity and eminence? Or do creativity and leadership have something to do with the temperaments associated with affective disease? We integrate concepts dating back to Greek psychological medicine and philosophy--especially work attributed to Aristotle--with modern data-based examination of the role of cyclothymic and related temperaments in the interface between mixity, the bipolar spectrum and normality. We place our query within the general framework of evolutionary biology and human nature. In doing so, we propose that affective disease--including mania and associated psychotic states--exist because they serve as the genetic reservoir for adaptive temperaments and the genes for genius. Affective disorder can therefore be regarded as the price of exceptional greatness. Thus, creative and eminent individuals, by virtue of their being exceptional, occupy a somewhat unstable terrain between temperament and affective disease.  相似文献   
90.
OBJECTIVE: Associations between eminent creativity and bipolar disorders have been reported, but there are few data relating non-eminent creativity to bipolar disorders in clinical samples. We assessed non-eminent creativity in euthymic bipolar (BP) and unipolar major depressive disorder (MDD) patients, creative discipline controls (CC), and healthy controls (HC). METHODS: 49 BP, 25 MDD, 32 CC, and 47 HC (all euthymic) completed four creativity measures yielding six parameters: the Barron-Welsh Art Scale (BWAS-Total, and two subscales, BWAS-Dislike and BWAS-Like), the Adjective Check List Creative Personality Scale (ACL-CPS), and the Torrance Tests of Creative Thinking--Figural (TTCT-F) and Verbal (TTCT-V) versions. Mean scores on these instruments were compared across groups. RESULTS: BP and CC (but not MDD) compared to HC scored significantly higher on BWAS-Total (45% and 48% higher, respectively) and BWAS-Dislike (90% and 88% higher, respectively), but not on BWAS-Like. CC compared to MDD scored significantly higher (12% higher) on TTCT-F. For all other comparisons, creativity scores did not differ significantly between groups. CONCLUSIONS: We found BP and CC (but not MDD) had similarly enhanced creativity on the BWAS-Total (driven by an increase on the BWAS-Dislike) compared to HC. Further studies are needed to determine the mechanisms of enhanced creativity and how it relates to clinical (e.g. temperament, mood, and medication status) and preclinical (e.g. visual and affective processing substrates) parameters.  相似文献   
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