Effect of deep cryogenic treatment on carbon segregation in Cr8Mo2SiV tool steel during tempering

Carbon segregation in Cr8Mo2SiV tool steel after common heat treatment (CHT) and deep cryogenic treatment (DCT) has been investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM) extraction replica and three-dimensional atom probe (3DAP) tests. The XRD results show that most of the retained austenite transformed to martensite after DCT. The TEM results confirm the transformation of blocky retained austenite to twin martensite during DCT. The 3DAP results reveal the segregation of carbon atoms and the maximum carbon fraction in carbon-rich regions increases after DCT. The peak carbon concentration in carbon-rich regions of SDC99 steel after CHT and DCT are 8 at. % and 15 at. %, respectively. The segregated carbon atoms grew into nuclei for nanoscale carbides precipitation on subsequent tempering.     

CysC在肾移植后急性排斥反应诊断中的价值

探讨CysC在肾移植术后诊断急性排斥反应中的价值。63例肾移植患者分为肾功能稳定组（49例）和排斥组（14例）,选10例单纯感染患者为对照组,检测CysC值,并与正常对照组（60例）比较。术后监测稳定组和排斥组CysC、BUN、SCr及CCr,对排斥组排斥前后CysC浓度变化以及CysC与SCr、CCr关系进行分析。结果为排斥组排斥前与排斥时CysC浓度差异有统计学意义（P〈0.01）;CCr在稳定组和排斥组与SCr、CysC均呈直线相关;感染组CysC与正常对照组差异无统计学意义（P〉0.05）。说明CysC可以用于肾移植术后急性排斥反应的早期诊断及与单纯感染鉴别诊断。     

非ST段抬高急性冠脉综合征药物治疗规范化分析

回顾性分析我院收治的129例非ST段抬高急性冠脉综合征患者的临床资料.对比在非ST段抬高急性冠脉综合征诊治上与最新指南的差距,找出改进措施.结果表明我院的临床实践与最新指南存在较大差距,在强化抗栓,调脂治疗,β受体阻滞剂及血管紧张素转换酶抑制剂类药物使用上均有待提高.今后应采取更加积极的措施,规范用药,以达到更好的预后和转归效果.     

ALI/ARDS患者糖皮质激素的治疗效果和时机

急性肺损伤/急性呼吸窘迫综合征(ALI/ARDS)是临床各科经常遇到的急症,其发病机制主要是中性粒细胞向炎症部位的移动,释放出大量的炎性介质和细胞因子,引起肺泡毛细血管膜通透性增高,弥漫性肺损伤和蛋白性肺泡水肿液聚集等病理生理改变。临床表现为呼吸困难、呼吸窘迫、顽固的低氧血症,虽然使用机械通气和呼气末正压通气(PEEP)后,其病死率有所下降,但仍然维持在50%左右。就糖皮质激素的作用机制,对不同原因引起的ALI/ARDS治疗效果,使用时机作一综述,期望对ALI/ARDS治疗过程中糖皮质激素的使用予以规范。     

急性肺损伤与急性呼吸窘迫综合征的诊断与治疗策略

急性肺损伤（ALI）和急性呼吸窘迫综合征（ARDS）是多个危险因素直接或间接引起肺部损伤的连续病理过程,以表现低氧血症为特征,ARDS是ALI严重末期的表现。低流量、呼气末正压（PEEP）保护性通气的措施可明显改善氧和,减轻机械通气肺损伤,降低病死率,明显优于传统通气方式。     

急性应激对工作记忆的影响受工作记忆负荷调节:来自电生理的证据

急性应激如何影响工作记忆还不清楚。采用电影片断诱发被试的急性应激或中性状态后,让其完成数字N-back任务并同时记录脑电。结果发现,低负荷工作记忆诱发的P3显著大于高负荷工作记忆;在0-back任务中,急性应激组诱发的P3显著大于控制组;而在2-back任务中,这种差异不显著。这些结果表明急性应激对工作记忆的影响受工作记忆负荷调节,支持了双竞争理论模型。     

Effects of morphine hydrochloride on social encounters between male mice

The effects of a single injection of morphine hydrochloride (0.3, 0.6, or 1.25 mg/kg) or physiological saline (0.9% NaCI) on the agonistic behaviour elicited by isolation in male mice were examined. Individually housed mice were exposed to anosmic “standard opponents” 30 minutes after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. Morphine (at 0.6 and 1.25 mg/kg) significantly and dose-dependently decreased time spent in offensive (“threat” and “attack”) and “digging” behaviours but markedly increased “non-social exploration” without a significant increase of “immobility.” The lowest dose was completely ineffective in producing changes in any of the behaviours studied. It is concluded that these results present a specific ethopharmacological profile characterized by suppression of aggressive behaviour, increase in non-social explotation, and no evident impairment of motor activity. © 1993 Wiley-Liss, Inc.     

Scaling Up the Self,Scaling Down the World: Self-objectification and the Politics of Carbon Offsets and Personalised Genomics

Two global initiatives, the Genographic Project and the Carbon Lottery, share an ambition to make abstract, global processes—human evolution and climate change—comprehensible and engaging to non-specialists. Despite their differences, they both do so by means of self-objectifications that scale up the selves of participants and scale down complex, spatio-temporal models of human–world relations. The author’s auto-ethnographic experiences in both initiatives illustrate how carbon calculators and personalised genomics involve a pragmatics of scale that evaluates and compares users on the basis of their relative expression of, or deviation from, a standard. Furthermore, this is not based on actual resources that participants do or do not possess, but on forms of capitalist exchange that underwrite carbon trading and population genomics, as experts and corporations make intellectual property derived from purportedly rare DNA and sustainable practices, which are typically indigenous and non-western. In fact, the global inequalities that make possible transactions in carbon offsets and genetic ancestry are obscured from view. As a result, though initiatives like the Genographic Project and Carbon Lottery may provide comprehensible self-objectifications, they potentially make the world more unequal in the process.     

Bond modulus and stability of covalent solids

The chemical stabilities of molecules are determined by their LUMO–HOMO energy gaps. For solids, the analogues of these are their energy band gaps. However, solids are aggregates of molecules, so an energy alone cannot characterize their stabilities. An intensive parameter is needed. Such a parameter is the gap energy per molecular volume. The author has coined the name ‘bond modulus’ for this parameter because it tends to be proportional to elastic moduli and it has the same dimensions. It applies primarily to covalent solids with localized bonding. It is proportional to chemical hardnesses and bulk moduli, as well as octahedral shear moduli and inverse polarizabilities.