Hypoxia represents one of the most extreme environmental conditions for both human beings and animals living at high al- titudes （Zhao et al., 2009）. Over the past few years, great attention has been focused on the ...Hypoxia represents one of the most extreme environmental conditions for both human beings and animals living at high al- titudes （Zhao et al., 2009）. Over the past few years, great attention has been focused on the genetic bases of adaption to high-altitude environments （Bigham et al., 2010; Simonson et al., 2010）. The domestic dog （Canisfamiliaris） is the first animal that developed an intimate relationship with human beings. Dogs migrated with human beings and have adapted to variety of ecological niches （Savolainen et al., 2002）. Our previous research revealed parallel evolution and convergent evolution in the adaptation of dogs and humans to the high-altitude environment of the Tibetan plateau （Wang et al., 2013, 2014）, suggesting that exploring the adaption of domestic dogs to high-altitude hypoxia is an interesting and important question.展开更多
The stochastic comparison and preservation of positive correlations for Levy-type processes on R^d are studied under the condition that Levy measure v satisfies f{0〈｜z｜≤1）｜z｜｜v（x, dz） - v（x, d（-z））｜ 〈 ...The stochastic comparison and preservation of positive correlations for Levy-type processes on R^d are studied under the condition that Levy measure v satisfies f{0〈｜z｜≤1）｜z｜｜v（x, dz） - v（x, d（-z））｜ 〈 ∞, x∈ R^d, while the sufficient conditions and necessary ones for them are obtained. In some cases the conditions for stochastic comparison are not only sufficient but also necessary.展开更多
Objectives: MRI is the most sensitive modality for local staging of breast cancer. Herceptin receptor over-expression is seen in 15% - 30% of breast tumours, and is associated with increased aggression, poorer prognos...Objectives: MRI is the most sensitive modality for local staging of breast cancer. Herceptin receptor over-expression is seen in 15% - 30% of breast tumours, and is associated with increased aggression, poorer prognosis, higher grade at diagnosis and increased lymphatic dissemination. This study aimed at evaluating the role of MRI in Herceptin receptor positive vs negative tumours. Methods: 193 pre-operative MRIs were performed in 2021 for staging of 162 Her-2 negative and 37 Her-2 positive tumours. Recall rates and further biopsies (ipsilateral/contralateral) were assessed in both groups, and MRI largest size was compared to pathological size of invasive cancer and DCIS. Results: 36.4% of Her-2 negative tumours were recalled;further ipsilateral malignancy was identified in 13.6%. Contralateral malignancy was identified in 1.2%. 29.7% of Her-2 positive tumours were recalled;further ipsilateral malignancy was identified in 16.2%. No contralateral malignancy was seen in Her-2 positive tumours. The OR of Her-2 positive tumours having ipsilateral foci of malignancy on MRI is 0.83 (CI 0.3, 2.2). Pathological size concordance with MRI size was seen in 70.3% of Her-2 negative, and 48.6% of Her-2 positive tumours. Discordance in both groups was due to MRI size overestimation (70.8% of Her-2 negative discordance;89.4% of Her-2 positive discordance). Conclusions: Pre-operative MRI did not detect significant increased additional foci in Her-2 positive tumours. Significant concordance with pathological size was not seen in both groups;MRI overestimation was the most frequent cause for discordance in both groups. Advances in Knowledge: This study compares MRI features of Her-2 positive and Her-2 negative tumours. It demonstrates that there is no significant increased multifocality or multicentricity of Her-2 positive tumours, but MRI over-estimates size in 30% of Her-2 negative and 51% of Her-2 positive cancers.展开更多
基金supported by the National Natural Science Foundation of China(No.91231108)the Breakthrough Project of Strategic Priority Program of the Chinese Academy of Sciences(No.XDB13000000)+1 种基金the Key Research Program of the Chinese Academy of Sciencesthe Youth Innovation Promotion Association,Chinese Academy of Sciences(to GDW)
文摘Hypoxia represents one of the most extreme environmental conditions for both human beings and animals living at high al- titudes （Zhao et al., 2009）. Over the past few years, great attention has been focused on the genetic bases of adaption to high-altitude environments （Bigham et al., 2010; Simonson et al., 2010）. The domestic dog （Canisfamiliaris） is the first animal that developed an intimate relationship with human beings. Dogs migrated with human beings and have adapted to variety of ecological niches （Savolainen et al., 2002）. Our previous research revealed parallel evolution and convergent evolution in the adaptation of dogs and humans to the high-altitude environment of the Tibetan plateau （Wang et al., 2013, 2014）, suggesting that exploring the adaption of domestic dogs to high-altitude hypoxia is an interesting and important question.
基金Supported in part by Creative Research Group Fund of the National Natural Science Foundation of China (No. 10121101)the "985" Project from the Ministry of Education in China
文摘The stochastic comparison and preservation of positive correlations for Levy-type processes on R^d are studied under the condition that Levy measure v satisfies f{0〈｜z｜≤1）｜z｜｜v（x, dz） - v（x, d（-z））｜ 〈 ∞, x∈ R^d, while the sufficient conditions and necessary ones for them are obtained. In some cases the conditions for stochastic comparison are not only sufficient but also necessary.
文摘Objectives: MRI is the most sensitive modality for local staging of breast cancer. Herceptin receptor over-expression is seen in 15% - 30% of breast tumours, and is associated with increased aggression, poorer prognosis, higher grade at diagnosis and increased lymphatic dissemination. This study aimed at evaluating the role of MRI in Herceptin receptor positive vs negative tumours. Methods: 193 pre-operative MRIs were performed in 2021 for staging of 162 Her-2 negative and 37 Her-2 positive tumours. Recall rates and further biopsies (ipsilateral/contralateral) were assessed in both groups, and MRI largest size was compared to pathological size of invasive cancer and DCIS. Results: 36.4% of Her-2 negative tumours were recalled;further ipsilateral malignancy was identified in 13.6%. Contralateral malignancy was identified in 1.2%. 29.7% of Her-2 positive tumours were recalled;further ipsilateral malignancy was identified in 16.2%. No contralateral malignancy was seen in Her-2 positive tumours. The OR of Her-2 positive tumours having ipsilateral foci of malignancy on MRI is 0.83 (CI 0.3, 2.2). Pathological size concordance with MRI size was seen in 70.3% of Her-2 negative, and 48.6% of Her-2 positive tumours. Discordance in both groups was due to MRI size overestimation (70.8% of Her-2 negative discordance;89.4% of Her-2 positive discordance). Conclusions: Pre-operative MRI did not detect significant increased additional foci in Her-2 positive tumours. Significant concordance with pathological size was not seen in both groups;MRI overestimation was the most frequent cause for discordance in both groups. Advances in Knowledge: This study compares MRI features of Her-2 positive and Her-2 negative tumours. It demonstrates that there is no significant increased multifocality or multicentricity of Her-2 positive tumours, but MRI over-estimates size in 30% of Her-2 negative and 51% of Her-2 positive cancers.
