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81.
82.
动物骨骼油脂的开发和利用是史前人类生存活动的重要组成部分。西方学者的研究表明,这一过程可能包含了敲骨取髓和骨脂提取两种不同的人类行为。相较于敲骨取髓,骨脂提取更为复杂,不仅要将骨骼砸碎成较小尺寸,还要加水煮沸骨骼碎片,过程中不断添冷水使水保持温和沸腾的状态,才能获得浮于水面的骨脂。目前,国内学者在此领域的研究多关注于前一行为而对后者鲜有论述。本文通过对相关科学文献的全面梳理,系统介绍了史前人类骨脂提取行为的鉴定分析手段和方法,进而探讨了这一行为在古人类资源利用程度、流动性、用火方式和烹饪技术等方面的指示意义与价值。  相似文献   
83.
《L'Anthropologie》2021,125(2):102865
The huge asiatic area does not show clear cut traditions but only fundamental tendencies proper to the human mind considered in its whole evolution mechanism. These tendencies are both clear and powerful: lightness of the skulls, technical blanks lighter, bone tools, pendants, and high mobility. The cultural European categories cannot be applied as such since the anthropological units were fuzzy, just like the huge steppes where they have developed. Europe just represents marginal caricatures and fixed of these general movements acting like waves perpetual and powerful.  相似文献   
84.
摘要 目的:探讨艾拉莫德对难治性类风湿关节炎患者骨密度和血清骨碱性磷酸酶(B-ALP)、I型胶原交联羧基末端肽(CTX-I)的机制。方法:选择2019年1月至2020年12月我院接诊的134例难治性类风湿关节炎患者,通过随机数表法分为观察组和对照组,每组67例。对照组给予甲氨蝶呤联合依那西普治疗,观察组给予艾拉莫德片联合依那西普治疗,均连续治疗12周。比较两组临床缓解率、实验室指标、类风湿关节炎患者病情评价(DAS28评分)、骨密度、血清B-ALP、CTX-I的变化和不良反应。结果:治疗后,观察组临床缓解率为90.00%,明显高于对照组72.50%(P<0.05);观察组红细胞沉降率(ESR)、C反应蛋白(CRP)、类风湿因子(RF)、抗环挂氨酸肽抗体(抗-CCP)表达和DAS28评分分别为(23.53±2.77)mm/h、(11.73±2.30)mg/L、(17.45±3.08)U/L、(43.22±7.17)RU/mL、(2.74±0.34)分,均明显低于对照组的(31.27±5.04)mm/h、(19.11±2.12)mg/L、(24.47±2.59)U/L、(55.23±7.44)RU/mL、(3.21±0.50)分,差异有统计学意义(P<0.05);观察组骨密度、血清B-ALP分别为(0.83±0.05)g/cm3、(117.02±15.65)U/L,均明显高于对照组(0.77±0.04)g/cm3、(101.19±9.59)U/L,观察组CTX-I为(0.36±0.04)μg/L,明显低于对照组(0.47±0.04)μg/L,差异有统计学意义(P<0.05);两组不良反应总发生率分别为4.44%和2.22%,差异无统计学意义(P>0.05)。结论:艾拉莫德联合依那西普治疗难治性类风湿关节炎效果显著,可明显改善骨密度、血清B-ALP、CTX-I的表达,提高临床缓解率,安全性好,值得应用推广。  相似文献   
85.
摘要 目的:探讨六味地黄丸联合小剂量雌孕激素替代疗法对围绝经期综合征(PMS)患者性激素、骨密度和血脂的影响。方法:研究对象选取2018年12月~2020年5月期间我院接收的PMS患者93例,根据乱数表法将患者随机分为对照组(n=46)和研究组(n=47),对照组给予小剂量雌孕激素替代疗法,研究组给予六味地黄丸联合小剂量雌孕激素替代疗法,28d为一个治疗周期,对比两组患者治疗3个周期后的疗效、性激素、腰椎L2~L4骨密度、血脂、子宫内膜厚度及不良反应。结果:治疗3个周期后,研究组的总有效率为91.49%(43/47),高于对照组的76.09%(35/46)(P<0.05)。治疗3个周期后,研究组改良Kupperman评分表(KMI)、总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、促卵泡刺激素(FSH)、促黄体生成素(LH)低于对照组,高密度脂蛋白胆固醇(HDL-C)、子宫内膜厚度、腰椎L2~L4骨密度、雌二醇(E2)高于对照组(P<0.05)。两组不良反应总发生率对比差异无统计学意义(P>0.05)。结论:六味地黄丸联合小剂量雌孕激素替代疗法治疗PMS患者,可有效缓解临床症状,提高骨密度,改善PMS患者的性激素及血脂水平,疗效确切。  相似文献   
86.
摘要 目的:探讨和总结使用网袋强化椎体成形术在骨质疏松椎体骨折围手术期的注意事项及相关对策。方法:回顾性分析2017年6月到2020年6月3年时间内,使用网袋强化椎体成形术治疗骨质疏松性椎体骨折患者共计112例。统计和比较患者在围手术期的各项指标,分析穿刺失败的原因及相关危险因素。结果:112例患者共涉及138个椎体。其中一期穿刺失败率(骨水泥分布不佳)为47个,占34.0%。骨水泥注入3 mL以下者为19个,占13.8%。骨水泥渗漏为36个,占26.1%。所有患者在术后3天及3月复查, VAS评分和ODI评分较前均有显著改善(P<0.05)。所有患者均未出现严重并发症(P>0.05)。结论:网袋强化椎体成形术在骨质疏松性椎体骨折的治疗中是一种理想的治疗方式,但在具体过程中仍有相关的经验和教训需要整理和总结。  相似文献   
87.
摘要 目的:观察椎间融合复位联合骨水泥强化椎弓根螺钉治疗老年重度腰椎滑脱的临床效果。方法:回顾性分析我院于2016年3月~2019年3月期间收治的老年重度腰椎滑脱患者92例,根据治疗方案的不同可将患者分为A组(n=44)和B组(n=48),A组给予椎弓根螺钉联合椎间融合复位治疗,B组给予骨水泥强化椎弓根螺钉联合椎间融合复位治疗,对比两组视觉疼痛模拟评分(VAS)、Oswestry功能障碍指数(ODI)及日本骨科协会(JOA)腰腿痛评分、临床指标、滑脱距离、滑脱率、椎间隙高度、椎间融合率、椎间孔高度、并发症及螺钉松动情况。结果:术后12个月,两组VAS、ODI、JOA评分均下降,且B组低于A组(P<0.05)。两组术中出血量对比组间无统计学差异(P>0.05),B组手术时间长于A组,住院时间短于A组,椎间融合率高于A组(P<0.05)。术后12个月,两组滑脱距离、滑脱率均下降,且B组小于A组(P<0.05)。术后12个月,两组椎间隙高度、椎间孔高度均升高,且B组高于A组(P<0.05)。两组并发症发生率组间对比无差异(P>0.05)。结论:老年重度腰椎滑脱患者椎间融合复位联合骨水泥强化椎弓根螺钉治疗,虽一定程度上延长了手术时间,但可促进临床症状,改善椎间高度及腰椎滑脱程度,缩短住院时间,且不增加并发症发生率。  相似文献   
88.
Commercial broiler premixes provide trace minerals (TMs) such as Zinc (Zn), Manganese (Mn) and Copper (Cu) above the birds' requirements to maximise broiler performance. High inclusion levels of TM and their low absorption in the broiler's gastrointestinal tract have led to increased TM levels in their litter, raising concerns about TM's accumulation in the environment from poultry litter. A 35-day broiler trial was conducted at a broiler facility with 2 880-day-old Cobb 500 broiler males. The objective was to evaluate whether decreasing inorganic Zn, Mn and Cu levels in broiler diets would have a negative effect on broiler growth parameters such as BW, average daily gain, cumulative feed intake (FI) and feed conversion ratio (FCR). Consequently, these minerals were supplemented at 100%, 50%, 25%, and 0% of the Cobb standards. No significant difference in FI and FCR was observed between the treatments for the first 21 days, and there were no significant differences in BW between the positive control, negative control (NC), and 50% of Cobb recommended levels at day 35. However, BW for the NC was significantly higher than the 25% level. These results show that reducing TM levels in broiler diets below commercially recommended levels had no negative effect on broiler performance, with the subsequent economic benefits for producers.  相似文献   
89.

Transgenic and knockout animal models are widely used to investigate the role of receptors, signaling pathways, and other peptides and proteins. Varying results are often published on the same model from different groups, and much effort has been put into understanding the underlying causes of these sometimes conflicting results. Recently, it has been shown that a P2X4R knockout model carries a so-called passenger mutation in the P2X7R gene, potentially affecting the interpretation of results from studies using this animal model. We therefore report this case to raise awareness about the potential pitfalls using genetically modified animal models, especially within P2 receptor research. Although purinergic signaling has been recognized as an important contributor to the regulation of bone remodeling, the process that maintains the bone quality during life, little is known about the role of the P2X4 receptor (P2X4R) in regulation of bone remodeling in health and disease. To address this, we analyzed the bone phenotype of P2rx4tm1Rass (C57BL/6J) knockout mice and corresponding wildtype using microCT and biomechanical testing. Overall, we found that the P2X4R knockout mice displayed improved bone microstructure and stronger bones in an age- and gender-dependent manner. While cortical BMD, trabecular BMD, and bone volume were higher in the 6-month-old females and 3-month-old males, this was not the case for the 3-month-old females and the 6-month-old males. Bone strength was only affected in the females. Moreover, we found that P2X4R KO mice carried the P2X7 receptor 451P wildtype allele, whereas the wildtype mice carried the 451L mutant allele. In conclusion, this study suggests that P2X4R could play a role in bone remodeling, but more importantly, it underlines the potential pitfalls when using knockout models and highlights the importance of interpreting results with great caution. Further studies are needed to verify any specific effects of P2X4R on bone metabolism.

  相似文献   
90.
The interphase region at the base of the growth plate includes blood vessels, cells and mineralized tissues. In this region, cartilage is mineralized and replaced with bone. Blood vessel extremities permeate this space providing nutrients, oxygen and signaling factors. All these different components form a complex intertwined 3D structure. Here we use cryo-FIB SEM to elaborate this 3D structure without removing the water. As it is challenging to image mineralized and unmineralized tissues in a hydrated state, we provide technical details of the parameters used. We obtained two FIB SEM image stacks that show that the blood vessels are in intimate contact not only with cells, but in some locations also with mineralized tissues. There are abundant red blood cells at the extremities of the vessels. We also documented large multinucleated cells in contact with mineralized cartilage and possibly also with bone. We observed membrane bound mineralized particles in these cells, as well as in blood serum, but not in the hypertrophic chondrocytes. We confirm that there is an open pathway from the blood vessel extremities to the mineralizing cartilage. Based on the sparsity of the mineralized particles, we conclude that mainly ions in solution are used for mineralizing cartilage and bone, but these are augmented by the supply of mineralized particles.  相似文献   
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