酸碱失衡的简易判断及代偿公式的编制

目的　提出酸碱失衡的简易判断方法及代偿公式的编制。方法　选择动脉血气指标 PH、Pa CO2 和HCO3-三项指标 ,以 Pa CO2 × 0 .6和 HCO3-的正常低高值 2 1～ 2 7作为酸碱平衡共同中性区 ,并以 Pa CO2 和HCO3- 为对象 ,编制酸碱失衡预计代偿公式 ,为单纯、复杂酸硷失衡的判断提供依据。结果　对大量临床病例及国内文献病例采用改进后的方法判断酸碱失衡 ,证实判断准确。结论　改进后的方法可准确判断酸碱失衡 ,易于掌握。     

Usefulness of measuring electrically evoked auditory brainstem responses in children with inner ear malformations during cochlear implantation

Conclusions: EABR is a reliable and effective way of objectively confirming device function and implant-responsiveness of the peripheral auditory neurons up to the level of the brainstem in cases of inner ear malformation. Objective: To investigate the usefulness of measuring the intra-operative electrically evoked compound action potential (ECAP) and electrically evoked auditory brainstem response (EABR) in patients with and without congenital inner ear anomalies during cochlear implantation. Method: Thirty-eight consecutive children (40 ears) aged 5 or younger with congenital profound hearing loss. Twenty-four (25 ears) lacked congenital inner ear anomalies. The 14 patients (15 ears) with a malformation had common cavities (four ears), incomplete partition type I (three ears), cochlea hypoplasia type III (three ears), enlarged vestibular aqueduct (four ears), and cochlear nerve canal stenosis (one ear). Main outcome measures are ECAP and EABR responses. Results: Of the 25 ears lacking any malformation, 21, three, and one showed ‘Good’, ‘Variable’, and ‘No’ ECAP responses, respectively, and 24 and one showed ‘Good’ and ‘Variable’ intra-cochlear responses, respectively. Of the 15 ears with a malformation, two showed ‘Good’ ECAP responses, nine had ‘Variable’ ECAP responses, and four showed ‘No’ ECAP responses. Moreover, five showed ‘Good’ EABR responses and 10 showed ‘Variable’ EABR responses.     

Molecular Evolution of Peste des Petits Ruminants Virus

Despite safe and efficacious vaccines against peste des petits ruminants virus (PPRV), this virus has emerged as the cause of a highly contagious disease with serious economic consequences for small ruminant agriculture across Asia, the Middle East, and Africa. We used complete and partial genome sequences of all 4 lineages of the virus to investigate evolutionary and epidemiologic dynamics of PPRV. A Bayesian phylogenetic analysis of all PPRV lineages mapped the time to most recent common ancestor and initial divergence of PPRV to a lineage III isolate at the beginning of 20th century. A phylogeographic approach estimated the probability for root location of an ancestral PPRV and individual lineages as being Nigeria for PPRV, Senegal for lineage I, Nigeria/Ghana for lineage II, Sudan for lineage III, and India for lineage IV. Substitution rates are critical parameters for understanding virus evolution because restrictions in genetic variation can lead to lower adaptability and pathogenicity.     

紫苏籽油对实验性牙槽骨骨质疏松的作用研究

目的：探讨紫苏籽油对去卵巢大鼠牙槽骨丢失的影响研究。方法：SD大鼠随机分为3组：对照组、去卵巢组和紫苏籽油治疗组。实验90d后取大鼠牙槽骨,测量牙槽骨组织形态计量学参数。结果：与去卵巢组相比：紫苏籽油治疗组牙槽骨骨量明显增多,%Tb.Ar升高34.47%（P〈0.05）,Tb.Th增加36.99%（P〈0.01）。结论：紫苏籽油能抑制去卵巢大鼠牙槽骨丢失。     

DNA single strand conformation polymorphism identifies five defined strains of hepatitis B virus (HBV) during an outbreak of HBV infection in an oncology unit

An outbreak of hepatitis B virus (HBV) infection in a children's oncology unit was identified in which 61 children were shown to have been infected, 59 of them asyptomatically. In order to establish whether intra-unit cross infection had occurred, we used the single strand conformational polymorphism (SSCP) technique to analyse viral isolates from 57 of the infected children and 40 unrelated controls. HBV-specific primers were designed to amplify a 189 bp fragment of DNA encompassing part of the hypervariable pre-S1 region of the HBV genome. Denatured PCR products were compared after electrophoresis through polyacrylamide gels and staining with silver. By SSCP analysis, the unrelated infections each yielded a unique electrophoretic banding pattern, indicative of a variety of distinct virus strains. In contrast, most of the oncology patients had been infected with one of only five different strains. Three major groups comprising 19, 16, and 9 patients, respectively, and two minor groups of 5 and 3 patients were identified. Results indicate the occurrence of multiple episodes of cross infection, and demonstrate the sensitivity and value of SSCP as a technique to establish common sources of infection. © 1996 Wiley-Liss, Inc.     

Rank-ordered regulation of motor units

Myoelectric signals were detected from the tibialis anterior muscle of 5 subjects with a quadrifilar needle electrode while the subjects generated isometric forces that increased linearly with time (10% of maximal voluntary contraction/s) up to maximal voluntary level. Motor unit firing rates were studied as a function of force throughout the full range of muscle force output. The relationship between force and firing rate was found to contain three distinct regions. At recruitment and near maximal force levels, firing rates increased more rapidly with force than in the intermediate region. Furthermore, in the regions with rapid increases, the rate of change of firing rate was correlated to the recruitment threshold, with higher recruitment threshold motor units displaying greater rates of change. In the intermediate region, all motor units had similar rates of change of firing rate. A weak positive correlation was found between initial firing rate and recruitment threshold. Firing rates of motor units at any instant were found to be ordered according to the recruitment order: at any given time in the contraction motor units with lower recruitment thresholds had higher firing rates than units with higher recruitment thresholds. Firing rates of all motor units were observed to converge to the same value at maximal forces. Mechanisms underlying motor unit recruitment and firing rate modulation are discussed in the context of a conceptual model. © 1996 John Wiley & Sons, Inc.     

新型冠状病毒感染核酸转阴后常见症的中医阐释

新型冠状病毒感染在中医上属于“疫病”,中国自古便有对疫病的记载。新型冠状病毒感染核酸转阴后,疫邪性质以湿为主,基本病机为正气未复,余邪未尽,主要病位在肺脾,本文将新型冠状病毒感染核酸转阴后常见症从生理到病理进行阐释,指导中医临床论治。     

警惕容易被误诊的遗传代谢病

遗传代谢病种类繁多,临床表现多样,缺乏特异性,个体差异较大,容易与常见疾病混淆,引起误诊和漏诊。遗传代谢病涉及多个器官系统,可以表现为神经精神损害、心血管疾病、肾脏疾病、肝脏疾病、血液系统疾病、皮肤病以及骨病等,临床诊断困难,需要依靠特殊生化检测和基因分析。因此,对于一些常见疾病、治疗效果不佳或有难以解释的临床症状和实验室检查时,需要进一步分析病因,减少误诊,才能精准治疗,改善预后。