目的:初步建立腮腺CT影像报告与数据系统(Parotid Imaging Reporting and Data System,PI-RADS),并探讨其临床应用价值。方法:纳入2013年1月至2016年12月间因腮腺肿物就诊于北京大学口腔医院并进行手术治疗的病例,回顾性评估所有病例的...目的:初步建立腮腺CT影像报告与数据系统(Parotid Imaging Reporting and Data System,PI-RADS),并探讨其临床应用价值。方法:纳入2013年1月至2016年12月间因腮腺肿物就诊于北京大学口腔医院并进行手术治疗的病例,回顾性评估所有病例的影像资料,获取相关影像特征,评估肿瘤恶性风险概率,并分为6个等级(1级,正常腮腺;2级,基本确定为良性病变或肿瘤;3级,无明确恶性病变证据但不能确定为良性病变;4级,怀疑为恶性肿瘤病变但证据不充分;5级,恶性肿瘤影像征象较充分;6级,有恶性肿瘤病理学证据)。结果:共纳入腮腺肿物病例897例次,其中良性病变905例次、恶性肿瘤98例次,影像诊断为2级、3级、4级和5级的病变中,恶性肿瘤的构成比分别为0.4%、5.7%、35.5%和96.7%,随PI-RADS分级呈逐渐增高趋势(Z=-15.579,P<0.001)。相邻等级[2级与3级(χ^2=12.048,P=0.001)、3级与4级(χ^2=75.231,P<0.001)、4级与5级(χ^2=32.266,P<0.001)]之间的恶性构成比差异有统计学意义。Cohen’s Kappa检验表明两位研究者分级诊断具有中度一致性(κ=0.614,P<0.001,95%CI:0.569~0.695)。结论:应用影像诊断分级方法对腮腺肿瘤性疾病的诊断和临床治疗有一定的帮助。展开更多
Western grassland is the main source of living and means of production of western inhabitants. For many years, desertification and poisonous-weeds growth in grassland were resulted from over-grazing, over-reclaiming, ...Western grassland is the main source of living and means of production of western inhabitants. For many years, desertification and poisonous-weeds growth in grassland were resulted from over-grazing, over-reclaiming, over-spading and population growth. Western natural ecological environment is destroyed severly. Meanwhile, it has restricted the sustainable development of animal husbandry. The fast spreading poisonous-weeds, which caused grassland ecology unbalance, is one of the considerable bioecology problems and an important index of grassland degeneration. Based on analysis and induction of previous data, this article introduced the situation of poisonous-weeds disaster of western grassland in recent decades, category and distribution of poisonous-weeds, integrated control and reasonable utilization.展开更多
Locoweed is a poisonous plant wildly distributed in most area of the world and can cause livestock poisoning or death with significant economic loss. The principal responsible for its toxicity is indolizidine alkaloid...Locoweed is a poisonous plant wildly distributed in most area of the world and can cause livestock poisoning or death with significant economic loss. The principal responsible for its toxicity is indolizidine alkaloid swainsonine, a new potential anticancer and antiviral drug. Astragalus strictus is mainly distributed in Tibet of China and is a serious hazard to the local livestock industry. To analyze its main toxic ingredients and supply more structural information and more accurate data, swainsonine has been isolated from this plant by D101 macroporous resin and the ^1H and ^13C chemical shifts of the compound has been assigned by 1D-NMR and 2D-NMR techniques. At the same time, complete assignments of swainsonine's ^13C spectral signals are reported.展开更多
文摘目的:初步建立腮腺CT影像报告与数据系统(Parotid Imaging Reporting and Data System,PI-RADS),并探讨其临床应用价值。方法:纳入2013年1月至2016年12月间因腮腺肿物就诊于北京大学口腔医院并进行手术治疗的病例,回顾性评估所有病例的影像资料,获取相关影像特征,评估肿瘤恶性风险概率,并分为6个等级(1级,正常腮腺;2级,基本确定为良性病变或肿瘤;3级,无明确恶性病变证据但不能确定为良性病变;4级,怀疑为恶性肿瘤病变但证据不充分;5级,恶性肿瘤影像征象较充分;6级,有恶性肿瘤病理学证据)。结果:共纳入腮腺肿物病例897例次,其中良性病变905例次、恶性肿瘤98例次,影像诊断为2级、3级、4级和5级的病变中,恶性肿瘤的构成比分别为0.4%、5.7%、35.5%和96.7%,随PI-RADS分级呈逐渐增高趋势(Z=-15.579,P<0.001)。相邻等级[2级与3级(χ^2=12.048,P=0.001)、3级与4级(χ^2=75.231,P<0.001)、4级与5级(χ^2=32.266,P<0.001)]之间的恶性构成比差异有统计学意义。Cohen’s Kappa检验表明两位研究者分级诊断具有中度一致性(κ=0.614,P<0.001,95%CI:0.569~0.695)。结论:应用影像诊断分级方法对腮腺肿瘤性疾病的诊断和临床治疗有一定的帮助。
基金funded by National Nature Science Foundation of China(31072175)Tibet Project Supported by Ministry of Agriculture of the People's Republic of China(20071010)
文摘Western grassland is the main source of living and means of production of western inhabitants. For many years, desertification and poisonous-weeds growth in grassland were resulted from over-grazing, over-reclaiming, over-spading and population growth. Western natural ecological environment is destroyed severly. Meanwhile, it has restricted the sustainable development of animal husbandry. The fast spreading poisonous-weeds, which caused grassland ecology unbalance, is one of the considerable bioecology problems and an important index of grassland degeneration. Based on analysis and induction of previous data, this article introduced the situation of poisonous-weeds disaster of western grassland in recent decades, category and distribution of poisonous-weeds, integrated control and reasonable utilization.
基金the National Natural Science Foundation of China (39770571)
文摘Locoweed is a poisonous plant wildly distributed in most area of the world and can cause livestock poisoning or death with significant economic loss. The principal responsible for its toxicity is indolizidine alkaloid swainsonine, a new potential anticancer and antiviral drug. Astragalus strictus is mainly distributed in Tibet of China and is a serious hazard to the local livestock industry. To analyze its main toxic ingredients and supply more structural information and more accurate data, swainsonine has been isolated from this plant by D101 macroporous resin and the ^1H and ^13C chemical shifts of the compound has been assigned by 1D-NMR and 2D-NMR techniques. At the same time, complete assignments of swainsonine's ^13C spectral signals are reported.