Posterior C1-C2 transarticular screw fixation in the treatment of displaced type II odontoid fractures in the geriatric population—review of seven cases

BACKGROUND

Seven geriatric patients presented with displaced Type II odontoid fractures. All patients underwent a posterior C1-C2 transarticular fixation between November 1994 and December 1996. Ages ranged between 63 and 88 years.

METHODS

Fractures were treated with placement of bilateral transarticular screws, allowing immediate fixation, except in one patient, for whom only a unilateral screw was used. An autograft interspinous strut was also placed, allowing three-point fixation. Mean follow-up was 10.6 months.

RESULTS

Six patients received rigid fixation and developed a stable union. One patient died before any follow-up could be obtained. Two other patients died within 1 year of unrelated causes. The remaining four patients remain active and independent. One intraoperative vertebral artery injury was identified. No clinical sequalae were noted.

CONCLUSION

Posterior transarticular screw fixation is a reasonable option in treating these controversial fractures. Seven geriatric patients tolerated this surgery well, and were mobilized early, avoiding complications related to external immobilization.     

Systematic spatiotemporal mapping reveals divergent cell death pathways in three mouse models of hereditary retinal degeneration

Calcium (Ca²⁺) dysregulation has been linked to neuronal cell death, including in hereditary retinal degeneration. Ca²⁺ dysregulation is thought to cause rod and cone photoreceptor cell death. Spatial and temporal heterogeneities in retinal disease models have hampered validation of this hypothesis. We examined the role of Ca²⁺ in photoreceptor degeneration, assessing the activation pattern of Ca²⁺-dependent calpain proteases, generating spatiotemporal maps of the entire retina in the cpfl1 mouse model for primary cone degeneration, and in the rd1 and rd10 models for primary rod degeneration. We used Gaussian process models to distinguish the temporal sequences of degenerative molecular processes from other variability sources.In the rd1 and rd10 models, spatiotemporal pattern of increased calpain activity matched the progression of primary rod degeneration. High calpain activity coincided with activation of the calpain-2 isoform but not with calpain-1, suggesting differential roles for both calpain isoforms. Primary rod loss was linked to upregulation of apoptosis-inducing factor, although only a minute fraction of cells showed activity of the apoptotic marker caspase-3. After primary rod degeneration concluded, caspase-3 activation appeared in cones, suggesting apoptosis as the dominant mechanism for secondary cone loss. Gaussian process models highlighted calpain activity as a key event during primary rod photoreceptor cell death. Our data suggest a causal link between Ca²⁺ dysregulation and primary, nonapoptotic degeneration of photoreceptors and a role for apoptosis in secondary degeneration of cones, highlighting the importance of the spatial and temporal location of key molecular events, which may guide the evaluation of new therapies.     

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三黄泻心汤煎煮过程中13种指标成分动态变化与分布规律研究

目的 建立经典名方三黄泻心汤（Sanhuang Xiexin Decoction,SXD）中13种指标成分（表小檗碱、黄连碱、巴马汀、小檗碱、黄芩苷、汉黄芩苷、黄芩素、汉黄芩素、大黄酸、芦荟大黄素、大黄素、大黄酚、大黄素甲醚）的含量同时测定方法,探索SXD煎煮过程中成分动态变化和分布规律,揭示SXD复合分散体系的制剂特征。方法 按照SXD传统煎煮方法制备煎液,建立样品中13种指标成分的含量同时测定方法,检测各指标成分在汤剂、离心上清液、离心沉积物中的含量;进一步地,分别制备浸泡结束、刚沸腾以及煎煮不同时间后的样品进行测定,绘制SXD煎煮过程中13种指标成分动态变化和分布规律图,分析煎煮过程中各成分在汤剂、离心上清液和离心沉积物中的含量变化情况。结果 SXD煎液中,含量最高的指标成分为黄芩苷（15.496 mg/g）,其次为小檗碱（3.048 mg/g）,含量最低的指标成分为大黄素甲醚（0.046 mg/g）;离心沉积物中黄连碱、小檗碱含量分别为离心上清液的4.13、3.44倍,离心上清液中黄芩苷、汉黄芩苷、芦荟大黄素含量分别为离心沉积物的2.04、2.76、1.33倍;煎煮过程中,自浸...     

反相高效液相色谱法优选黄芩中黄芩苷的提取工艺

目的:研究黄芩中黄芩苷的最佳提取工艺.方法:采用L9(34)正交试验法考察黄芩中黄芩苷提取的各影响因素(A乙醇浓度、B提取时间、C容积量),以黄芩苷含量为指标进行直观分析及方差分析,确定最佳提取工艺.结果:黄芩中黄芩苷的最佳提取工艺条件为A1B3C3,即50%乙醇、热回流提取3 h、12倍药材量的乙醇.结论:此提取工艺简单易行,稳定可行,适于黄芩的大规模提取.     

Mapping the musician brain

The understanding of the relationships between music and the brain is a legitimate goal of neuroscientific research. In spite of an already large body of experimental investigation, however, the outcome has not been as satisfactory as expected, to the point that some have voiced their incredulity at the feasibility of mapping musical functions onto cerebral structures. There are indeed considerable inconsistencies in the literature bearing on the neurobiological substrates of musical functions. Before giving in to skepticism, though, it is appropriate to examine whether such inconsistencies are unavoidable and a necessary outcome of neuroscientific investigation into musical functions. This paper, therefore, examines some of the reasons that may be responsible for the inconsistencies. Beyond the superficial similarities between language and music, these two domains are functionally distinct, yet neuropsychological research in music and its neurobiological substrates has been modeled after that in verbal language, borrowing concepts and methods that were not entirely suited to the study of musical functions. An examination of the diverse factors inherent in any study of music-brain relationships reveals a variety of potential sources of difficulties, which, if properly controlled, would guarantee higher consistency and enhance the reliability of experimental findings. It is thus suggested that progress in understanding music-brain relationships may result from (1) explicitly outlining the structural cognitive architecture of musical functions; (2) formulating the problems in terms of underlying operations rather than in terms of vague and unspecified dichotomic views of hemisphere processing; (3) designing experiments that are musically valid and coherent, and that do not lend themselves to multiple strategies; (4) setting up appropriate controls to ensure that subjects are performing as expected; (5) restricting the investigation to musically literate individuals; (6) selecting, among such individuals, a homogeneous set of subjects sharing common musical abilities; and (7) using investigatory techniques that yield reliable evidence of local cerebral involvement in realizing the tasks under study. © 1993 Wiley-Liss, Inc.     

利用碱法草浆造纸固体废弃物生产有机-无机复混肥的农田试验

利用碱法草浆造纸产生的固体废弃物:白泥、木质素、生化污泥及废草渣,经堆肥处理后与无机肥复配、造粒,生产有机-无机复混肥,并进行了农田试验.结果表明,该有机-无机复混肥可有效提高作物产量,改善作物品质,并对土壤具有显著的改良作用.该研究对防止碱法草浆造纸的固体废弃物对环境的污染具有重要意义.     

试验设计类型之无法考察交互作用的多因素设计:嵌套设计

本文目的是介绍一种无法考察交互作用的多因素设计类型,即嵌套设计。通过介绍四个具体实例,总结出两种不同的嵌套设计:(1)试验因素之间具有自然属性上的嵌套关系;(2)试验因素对评价指标的影响存在主次关系。通过对实例的解读,揭示嵌套设计具有一个其他多因素设计所缺乏的明显特点,即因素的水平是"纵向连接"而不是"横向组合"的;并从正确合理应用的角度考量,指出了使用嵌套设计时应注意的事项。     

黄芪炮制历史沿革研究

目的:弄清黄芪历代炮制演变轨迹、现代全国各地炮制规范概况,为研究者提供现代研究思路。方法:通过大量地查阅、整理、分析古代及现代医药文献,全面综述古今黄芪炮制方法、探讨炮制机理。结果:自汉代开始,经历南北朝、唐、宋、元、明、清等时期,记载的炮制方法共有30多种,传统炮制理论成熟。结论:黄芪古代炮制方法种类丰富、炮制理念成熟,目前流传下来应用普遍、研究最多的主要为蜜炙黄芪及黄芪片,其他方法及其炮制品已不是研究及使用主流。但历代沿用的酒制、米制、盐制等炮制品确有无可替代的作用,因而也应被进一步继承创新。