超声骨密度仪高精度测量技术的研究

目的对市售的韩国超声骨密度仪（型号为OsteoProUBD2002A）进行改进,设计以现场可编程门阵列（fieldprogrammablegatearray,FPGA）作为控制芯片的高精度超声骨密度仪,克服其准确度不高及检测速率低等问题。方法该系统以FPGA芯片XC3S250E-4为核心,采用MAX1449芯片进行模数转换,使用K6T4016V3C—TF70进行数据存储,通过USB芯片FT232H进行数据传输。最后对系统的传输速度和整体性能进行了测试。结果实验结果证实该系统采样率高,数据传输速度快。结论该高精度测量系统是超声骨密度仪性能提升的核心。     

Development of calcium phosphate/sulfate biphasic cement for vital pulp therapy

ObjectivesBioactive calcium phosphate cement (CPC) has been used widely to repair bone defects because of its excellent biocompatibility and bioactivity. However, the poor handling properties, low initial mechanical strength, and long setting time of CPC limit its application in vital pulp therapy (VPT). The aim of this study was to synthesize biphasic calcium phosphate/sulfate cements and evaluate the feasibility of applying these cements in VPT.MethodsThe physical, chemical, and mechanical properties of CPC were improved by mixing the cement with various amounts of α-calcium sulfate hemihydrate (CSH). The hydration products and crystalline phases of the materials were characterized using scanning electron microscopy and X-ray diffraction analysis. In addition, the physical properties, such as the setting time, compressive strength, viscosity, and pH were determined. Water-soluble tetrazolium salt-1 and lactase dehydrogenase were used to evaluate cell viability and cytotoxicity.ResultsThe developed CPC (CPC/CSH cement), which contains 50 wt% CSH cement, exhibited no obvious temperature increase or pH change during setting when it was used as a paste. The initial setting time of the CPC/CSH biphasic cement was substantially shorter than that of CPC, and the initial mechanical strength was 23.7 ± 5.6 MPa. The CPC/CSH cement exhibited higher viscosity than CPC and, thus, featured acceptable handling properties. X-ray diffraction analysis revealed that the relative peak intensity for hydroxyapatite increased, and the intensity for calcium sulfate dehydrate decreased as the amount of CPC was increased. The cell viability and cytotoxicity test results indicated that the CPC/CSH cement did not harm dental pulp cells.SignificanceThe developed CPC/CSH biphasic cement exhibits substantial potential for application in VPT.     

Upregulation of neuregulin-1 reverses signs of neuropathic pain in rats

Background: Peripheral nerve injury can result in neuropathic pain, a chronic condition of unclear cause often poorly responsive to current treatments. One possibility is that nerve injury disrupts large A-fiber-mediated inhibition of C-fiber-evoked responses in spinal dorsal horn neurons, leading to central sensitization. A recent study provided a potential molecular mechanism; large dorsal root ganglion (DRG) neurons secrete neuregulin-1 (NRG1), which binds to erbB4 receptors on interneurons and promotes GABA release to inhibit C-fiber-evoked nociceptive transmission. Thus, reduced NRG1 expression following nerve injury could induce chronic pain by disinhibition. We examined if DRG expression of NRG1 is in fact reduced in a rat model of neuropathic pain and if exogenous NRG1 alleviates behavioral signs of this condition. Methods: Three neuropathic pain models were established in rats: spared nerve injury of the tibial and common peroneal nerves (SNI model), intraplantar injection of complete Freund’s adjuvant (CFA model), and subcutaneous formalin injection. NRG1 expression was assessed by immunofluorescent staining, hyperalgesia by paw withdrawal threshold to von Frey filament stimulation, and pain-like behavior by spontaneous flinching. Results: NRG1 protein immunoreactivity was reduced in the rat DRG after SNI. Intrathecal administration of neuregulin-1beta 1 (NRG1-1), a 62 amino acid NRG1 mimetic, transiently increased paw withdrawal threshold in SNI model and reduced flinching in the formalin injection model. Conclusion: Our results are consistent with a model of neuropathic pain whereby peripheral nerve injury reduces NRG1-mediated inhibition of nociceptive signaling. Modulating NRG1 may have therapeutic potential for treating neuropathic pain.     

在人工气道纤维支气管镜检查中使用不同氧疗模式的对比研究

目的探讨带有人工气道的患者在行纤维支气管镜检查治疗中使用不同氧疗模式的效果。方法采用便利抽样法,选择联勤保障部队第九八三医院重症医学科2018年3月—2019年3月收治的带有人工气道并需进行支气管镜检查的104例重症肺炎的患者为研究对象,随机分为对照组(52例)和试验组(52例)。比较两组患者干预前后生命体征变化。结果干预前,两组患者血压、心率比较,差异无统计学意义(P>0.05);干预中、干预后,对照组血压﹑心率均高于试验组,两组比较差异有统计学意义(P<0.05)。干预后,试验组患者低氧血症、心律失常发生例数均低于对照组,但两组比较差异无统计学意义(P>0.05)。结论高流量湿化氧疗仪在人工气道患者纤维支气管镜检查治疗中可降低患者术中的缺氧量,提高患者的舒适度,稳定生命体征,降低不良反应。     

The association of gender, age, body mass index, and vital signs in healthy plateletapheresis donors

In order to determine the association between gender, age, body mass index and vital signs among healthy plateletapheresis donors, the mean and median values from the most recent donations of 236 plateletapheresis donors were calculated for age, body mass index (BMI), oral temperature, blood pressure (BP), and pulse. Values of these parameters were compared after stratification by gender, age, and BMI and multiple regression analysis between parameters performed. Gender, age, and BMI were associated with significant differences in vital signs of healthy plateletapheresis donors.     

Event management for large scale event-driven digital hardware spiking neural networks

The interest in brain-like computation has led to the design of a plethora of innovative neuromorphic systems. Individually, spiking neural networks (SNNs), event-driven simulation and digital hardware neuromorphic systems get a lot of attention. Despite the popularity of event-driven SNNs in software, very few digital hardware architectures are found. This is because existing hardware solutions for event management scale badly with the number of events. This paper introduces the structured heap queue, a pipelined digital hardware data structure, and demonstrates its suitability for event management. The structured heap queue scales gracefully with the number of events, allowing the efficient implementation of large scale digital hardware event-driven SNNs. The scaling is linear for memory, logarithmic for logic resources and constant for processing time. The use of the structured heap queue is demonstrated on a field-programmable gate array (FPGA) with an image segmentation experiment and a SNN of 65 536 neurons and 513 184 synapses. Events can be processed at the rate of 1 every 7 clock cycles and a 406×158 pixel image is segmented in 200 ms.     

硬膜外分娩镇痛对妊高征患者分娩前后生命体征及分娩结局的分析

目的 分析硬膜外分娩镇痛对妊高征产妇分娩的生命体征及分娩结局的影响。方法对比98例布比卡因持续硬膜外麻醉和120例未实施无痛措施的妊高征患者分娩前后生命体征及分娩结局的差异。结果 持续硬膜外麻醉与未实施无痛措施的患者比较产程时间，催产素及产后出血差异无统计学意义（P〈0．05）；显著缓解疼痛（P〈0．01）；显著减少产钳协助和剖宫手术（P〈0．05）；显著减少胎儿宫内缺氧及新生儿窒息的比例（P〈0．05）；各阶段过程中，MAP（mmHg），HR（次／min）差异有统计学意义（P〈0．01）。结论 持续硬膜外分娩镇痛有效缓解疼痛，减少胎儿缺氧，有助于分娩过程。     

The demography of maternal mortality--seven Swedish parishes in the 19th century

Complications of childbirth is a leading death cause for women of reproductive ages in the developing countries today. The unique Swedish population statistics from the 19th century permit comparable historical studies. In seven Swedish parishes 170 maternal deaths were observed - 595 per 100,000 live births. Eclampsia, obstructed labor and hemorrhage were responsible for 92 deaths, and puerperal sepsis for only 15 deaths. Indirect obstetrical deaths, like pneumonia, tuberculosis, dysentery and heart diseases, accounted for 30.8% (41/133) of the specified death causes. With a time limit of 1 year instead of 42 days following delivery, maternal mortality was increased by 17%. Out of 14 married women 1 died from childbirth. Maternal deaths accounted for 40-50% of all deaths in the central ages of reproduction, leaving the motherless children with a highly increased death risk. Of the live born, 3% survived 5 years after the mothers' death. Of children aged 1-5 only 13% survived 5 years after the mothers death.     

从嗓音疾病调查结果看"歌唱伤气"理论

目的:为探讨“歌唱伤气”理论的正确性。方法:采用整群随机抽样方法,对比调查了502名歌唱学生和200名非歌唱学生嗓音疾病、气虚证和气滞证、肺活量、声时及歌唱学生发病诱因等情况。结果:歌唱学生气虚和气滞证发生率明显高于非歌唱学生(P<0.01),且歌唱学生嗓音疾病患者气虚和气滞证、肺活量值、声时值均与歌唱学生无嗓音疾病者及非歌唱学生嗓音疾病患者有非常显著差异(P<0.01)。歌唱学生气虚和气滞证人数比例随练声时间增加而增多,超过60分钟以上者高于60分钟以下者,高音歌唱者高于中音及低音歌唱者,惯用硬起音者高于不惯用者,胸腹式联合呼吸者低于单纯胸式或腹式呼吸者(P<0.01)。结论:“歌唱”引起的“伤气”是嗓音疾病产生的主要原因,“歌唱伤气”理论具有正确性和科学性。     

中医证候规范化理论基础初探

中医证候长期不能规范的根本原因是规范的基础不一致 ,邪正斗争贯穿于一切疾病过程中 ,正虚邪实是疾病和证候的本质。用脏腑定病位 ,审察邪正斗争态势 ,确定病性、病势 ;以病统证 ,以症定证 ,这是规范的基本方法。