Emergency medical services systems in the United States and China: a developmental comparison

International emergency medical services (EMS) consultation requires many sensitivities to cross-cultural issues. Contemporary EMS models in developed countries have, by necessity, a systems framework. This study compares evolving EMS systems in the United States and China. It is concluded, that, no matter what the potential and cultural differences might be, a systems framework inherently will emerge in EMS development. As such, the EMS components recognized often will expose an evolving systems approach with more similarities than differences and can reveal strategies for improvement. Providing a developmental comparison process is a necessary first phase in analysis of a country's systems development or restructuring.     

Vagal Nerve Monitoring during Parapharyngeal Space Tumor Removal

The vagus nerve innervates the intrinsic and extrinsic laryngeal musculature as well as the complex pharyngeal plexus. Acute paralysis of this nerve results in dysfunctional speech, deglutition, and airway protection. These untoward effects, which lead to additional infectious and aerodigestive complications, may arise following manipulation of the vagus nerve during the surgical removal of a variety of neoplasms found in the parapharyngeal space.The vagal nerve has been intraoperatively monitored in an effort to maintain its anatomic and functional integrity. Bipolar hook-wire electrodes are introduced transcutaneously through the cricothyroid membrane and are guided into the vocalis muscle by an assistant performing direct laryngoscopy. Continuous, real-time monitoring of the vagal nerve is provided by audio and visual feedback to the operating surgeon. Potentially injurious stretching, heating, and compression of the nerve are easily detected, and monopolar stimulation of the nerve is used to map the nerve's course through the tumor bed.This presentation outlines our technique for vagal nerve monitoring in patients with tumors of the parapharyngeal space and intact preoperative vocal cord mobility. Selected cases are presented and illustrated through intraoperative and postoperative videotapes.     

美尼尔与美尼尔病

美尼尔生活在法国大革命之后医学繁荣时代。他长期从事耳科学实践活动,发现了传统上认为是卒中型脑充血的内耳疾病。尽管这种以他名字命名的疾病─美尼尔病被后世误解,但是,他的发现终于被科学发展所证实。现今人们正在为深入研究美尼尔病作不懈的努力,以期彻底将之征服。     

Effects of excitatory amino acid antagonists on social recognition of male rats

The effects of NMDA and non-NMDA glutamate receptor antagonists were evaluated on social recognition of adult male rats. Adult animals were injected (s.c.) with drug or saline immediately after the initial exposure to a juvenile male, 21-24 days old, and re-exposed to the same or to a novel juvenile 30min later. If the time spent by animals in social investigation during re-exposure to the same juvenile was comparable with the time measured during the initial exposure and with the time of animals re-exposed to a novel juvenile, the effect of a drug was designated as amnesia. Such an effect was found in adult animals administered 1 and 1.5mg/kg phencyclidine, 0.1mg/kg dizoclipine, 2.5mg/kg CPP, and 4mg/kg CGS 19755. Amnesic effects were observed at doses not affecting motor performance. No amnesic effect was produced by CNQX and NBQX (2.5, 5 and 10mg/kg). These results show that while recognition capacity in adult male rats is disrupted by several NMDA antagonists, non-NMDA antagonists do not interfere with short-term retention of individual odours. This suggests that NMDA glutamate receptors may be involved in the processing of socially relevant olfactory information.     

The value of placental glutathione S-transferase and {gamma}-glutamyl transpetidase as markers of altered foci during hamster pouch carcinogenesis

This study investigated the value of an immunohistochemicaldemonstration of placental glutathione S-transferase (GST P)and a histochemical demonstration of -glutamyl trans peptidase(GGT) for the detection of putative preneoplastic lesions andsquamous cell carcinomas in the Syrian golden hamster buccalpouches treated with 7,12-dimethylbenz[a]anthracene (DMBA).The results showed that GST-P foci appeared earlier than GGTfoci, that the GST-P foci were much more numerous than GGT fociand that most of the GGT positive foci were GST-P positive.All tumors stained strongly positive for GST-P. Only 62.5% oftumors stained for GGT and the staining was usually weak andinvolved only the superficial layer of the epithelium or keratin,suggesting that the enzyme activity in the basal cells had decreasedwith formation of neoplasms. The length percentage of basalcells that were GST-P positive increased rapidly during theexperiment and by week 12,25% of the basal cells exhibited GST-Pstaining. Such rapid expansion of the putative initiated cellsmay explain the early development of chemically induced invasivesquamous cell carcinoma (weeks 10–12) in 100% of hamsters.     

Growth-factor regulation of mdm-2 messenger-RNA expression

We have investigated the growth factor regulation of mdm-2 mRNA levels in mouse embryo fibroblasts, whose growth is controlled by platelet-derived growth factor (PDGF) and insulin-like growth factor I (IGF-I). We find that both growth factors up-regulate the expression of mdm-2 mRNA, independently of each other.