为开发高腰海胆Mespilia globulus人工繁育技术,对高腰海胆进行了人工催产、授精、孵化和幼体培育,在显微镜下观察了高腰海胆从受精卵到稚胆的发育过程,并测量了受精卵、各期胚胎和幼体的大小。结果表明:利用注射KCl溶液法催产,可以顺...为开发高腰海胆Mespilia globulus人工繁育技术,对高腰海胆进行了人工催产、授精、孵化和幼体培育,在显微镜下观察了高腰海胆从受精卵到稚胆的发育过程,并测量了受精卵、各期胚胎和幼体的大小。结果表明:利用注射KCl溶液法催产,可以顺利促使高腰海胆排放精卵,排出的精卵受精率为92.3%±1.4%;高腰海胆胚胎和幼体发育过程包括受精卵、卵裂期、囊胚期、旋转囊胚期、原肠期、棱柱幼体、二腕幼体、四腕幼体、六腕幼体、八腕幼体和稚胆等阶段;在水温为25~26℃条件下,受精卵在50 min后开始卵裂,10 h后进入旋转囊胚期,15 h后进入原肠期,23 h后进入棱柱幼体期,1 d 14 h进入二腕幼体阶段,2 d 10 h进入四腕幼体阶段,7 d 13 h后进入六腕幼体阶段,9 d 18 h后进入八腕幼体阶段,11 d后变态为稚胆。研究表明,高腰海胆各期浮游幼体尺寸与其他海胆种类相近,但浮游期相对较短,人工育苗难度相对较低。展开更多
目的:分析接受再次手术的复发性库欣病患者的缓解率及其影响因素。方法:回顾性分析2003年1月至2018年12月行第2次经蝶手术的22例复发性库欣病患者(随访超过6个月)的临床资料。分析患者第2次术前生化指标、双侧岩下窦静脉采血结果、MRI...目的:分析接受再次手术的复发性库欣病患者的缓解率及其影响因素。方法:回顾性分析2003年1月至2018年12月行第2次经蝶手术的22例复发性库欣病患者(随访超过6个月)的临床资料。分析患者第2次术前生化指标、双侧岩下窦静脉采血结果、MRI结果。同时评估术后血清皮质醇、24 h尿游离皮质醇(urinary free cortisol,UFC)和病理结果。术后缓解定义为术后血皮质醇小于50μg/L或者24 h UFC值处于正常范围。分析两次术前MRI结果、促肾上腺皮质激素(ACTH)水平、24 h UFC、肿瘤大小等因素与第2次术后缓解的相关性。结果:16例(72.7%)患者在第2次术后获得缓解,平均随访时间为64.5个月。22例患者初次术前均有明显库欣病影像学证据,其中有8例(36.4%)再次手术前无复发的明显影像学证据。MRI显示存在垂体占位的14例患者中10例(71.4%)再手术后缓解;8例MRI未显示明显肿瘤的患者中6例于再次手术后缓解。微腺瘤患者(75.0%,15/20)的再手术后缓解率略优于大腺瘤患者(50.0%,1/2),但差异无统计学意义。缓解患者二次术前ACTH和UFC水平均低于术后未缓解组,但差异无统计学意义。二次术后,病理结果显示有ACTH阳性腺瘤证据的患者有更高的缓解率(86.7%vs 42.9%,P<0.05),而复发时的年龄较大非手术结果的不利因素。结论:二次手术对于初次手术后复发的库欣病患者是一个较好的选择,而其远期效果须延长随访时间进一步验证,缓解相关因素须增加病例进一步筛选。展开更多
An industrial trial was conducted on a billet-casting machine at Atlas Steel, Canada, during which a mould was instrumented with 52 thermocouples. The measured data of ten heats were collected to determine mould wall ...An industrial trial was conducted on a billet-casting machine at Atlas Steel, Canada, during which a mould was instrumented with 52 thermocouples. The measured data of ten heats were collected to determine mould wall temperature profiles for different steel grades at different casting speeds. Based on these data, heat fluxes were calculated with inverse heat conduction model. Heat fluxes for different operating parameters were compared and analyzed.展开更多
With the aid of ANSYS software, the effect of different mould external part materials on magnetic flux density and electromagnetic body force in the liquid aluminum was investigated. Calculated results showed that mag...With the aid of ANSYS software, the effect of different mould external part materials on magnetic flux density and electromagnetic body force in the liquid aluminum was investigated. Calculated results showed that magnetic flux density and electromagnetic body force in the aluminum melt are greatly increased when the external part of mould is made from A3 steel. A low-frequency electromagnetic casting 6063 aluminum alloy experiment was conducted in the laboratory with the current value of 120 A and frequency value of 15 Hz. The experiment showed that the microstructure and surface quality of ingots with mould outer part made from A3 steel under low-frequency electromagnetic field are better than that of ingots with mould outer part made from austenitic stainless steel. The surface of the ingots with mould outer part made from A3 steel is smooth and free from exudations and cold shut defects. The as-cast microstructure consists of fine, uniformly distributed equiaxed grains.展开更多
文摘为开发高腰海胆Mespilia globulus人工繁育技术,对高腰海胆进行了人工催产、授精、孵化和幼体培育,在显微镜下观察了高腰海胆从受精卵到稚胆的发育过程,并测量了受精卵、各期胚胎和幼体的大小。结果表明:利用注射KCl溶液法催产,可以顺利促使高腰海胆排放精卵,排出的精卵受精率为92.3%±1.4%;高腰海胆胚胎和幼体发育过程包括受精卵、卵裂期、囊胚期、旋转囊胚期、原肠期、棱柱幼体、二腕幼体、四腕幼体、六腕幼体、八腕幼体和稚胆等阶段;在水温为25~26℃条件下,受精卵在50 min后开始卵裂,10 h后进入旋转囊胚期,15 h后进入原肠期,23 h后进入棱柱幼体期,1 d 14 h进入二腕幼体阶段,2 d 10 h进入四腕幼体阶段,7 d 13 h后进入六腕幼体阶段,9 d 18 h后进入八腕幼体阶段,11 d后变态为稚胆。研究表明,高腰海胆各期浮游幼体尺寸与其他海胆种类相近,但浮游期相对较短,人工育苗难度相对较低。
文摘目的:分析接受再次手术的复发性库欣病患者的缓解率及其影响因素。方法:回顾性分析2003年1月至2018年12月行第2次经蝶手术的22例复发性库欣病患者(随访超过6个月)的临床资料。分析患者第2次术前生化指标、双侧岩下窦静脉采血结果、MRI结果。同时评估术后血清皮质醇、24 h尿游离皮质醇(urinary free cortisol,UFC)和病理结果。术后缓解定义为术后血皮质醇小于50μg/L或者24 h UFC值处于正常范围。分析两次术前MRI结果、促肾上腺皮质激素(ACTH)水平、24 h UFC、肿瘤大小等因素与第2次术后缓解的相关性。结果:16例(72.7%)患者在第2次术后获得缓解,平均随访时间为64.5个月。22例患者初次术前均有明显库欣病影像学证据,其中有8例(36.4%)再次手术前无复发的明显影像学证据。MRI显示存在垂体占位的14例患者中10例(71.4%)再手术后缓解;8例MRI未显示明显肿瘤的患者中6例于再次手术后缓解。微腺瘤患者(75.0%,15/20)的再手术后缓解率略优于大腺瘤患者(50.0%,1/2),但差异无统计学意义。缓解患者二次术前ACTH和UFC水平均低于术后未缓解组,但差异无统计学意义。二次术后,病理结果显示有ACTH阳性腺瘤证据的患者有更高的缓解率(86.7%vs 42.9%,P<0.05),而复发时的年龄较大非手术结果的不利因素。结论:二次手术对于初次手术后复发的库欣病患者是一个较好的选择,而其远期效果须延长随访时间进一步验证,缓解相关因素须增加病例进一步筛选。
基金The project was supported by the Foundation of NSFC-Shanxi Coal-based Low Carbon Joint Fund(U1610254)Natural Science Foundation of Shanxi Province(201901D111006).
文摘An industrial trial was conducted on a billet-casting machine at Atlas Steel, Canada, during which a mould was instrumented with 52 thermocouples. The measured data of ten heats were collected to determine mould wall temperature profiles for different steel grades at different casting speeds. Based on these data, heat fluxes were calculated with inverse heat conduction model. Heat fluxes for different operating parameters were compared and analyzed.
基金The project (G199906490501) was supported by the National Key Fundamental Research and Development Program of China
文摘With the aid of ANSYS software, the effect of different mould external part materials on magnetic flux density and electromagnetic body force in the liquid aluminum was investigated. Calculated results showed that magnetic flux density and electromagnetic body force in the aluminum melt are greatly increased when the external part of mould is made from A3 steel. A low-frequency electromagnetic casting 6063 aluminum alloy experiment was conducted in the laboratory with the current value of 120 A and frequency value of 15 Hz. The experiment showed that the microstructure and surface quality of ingots with mould outer part made from A3 steel under low-frequency electromagnetic field are better than that of ingots with mould outer part made from austenitic stainless steel. The surface of the ingots with mould outer part made from A3 steel is smooth and free from exudations and cold shut defects. The as-cast microstructure consists of fine, uniformly distributed equiaxed grains.
