Tiotidine and cimetidine--kinetics and dynamics

Tiotidine and cimetidine kinetics and dynamics were compared to assess mechanisms of the longer duration of effect of tiotidine in man. Both drugs has similar lag times for absorption. Tiotidine with a meal was more slowly absorbed than when fasting and was also more slowly absorbed than cimetidine with a meal. The elimination rates for both drugs did not differ; they were both approximately 2 to 3 hr. Oral doses of cimetidine achieved areas under the plasma concentration curve approximately three times that of tiotidine but these concentrations were only 1/10 as potent. The cimetidine concentration inducing 50% inhibition of food-stimulated gastric acid secretion was 0.41 +/- 0.04 whereas it was 0.04 +/- 0.003 microgram/ml for tiotidine. The effect of tiotidine lasted longer than that of cimetidine because the doses recommended for use in man resulted in higher concentrations in plasma relative to effective concentration than clinical doses of cimetidine.     

Prenatal and postnatal growth and development of the foot and ankle

The intent of this article is to present a detailed overview of the normal prenatal and postnatal development and growth of the lower limb with special emphasis on the ankle-foot complex. The effects of physiologic load and its components of duration, timing, and direction are discussed. The results of abnormal amount, timing, duration, or direction of load on the prenatal and postnatal human are discussed with examples of foot deformity provided for clarification. Principles of therapeutic force application for the reversal of deformity are formulated.     

Perceiving and naming actions and objects

Neuropsychological studies have suggested differences in the cortical representations of verbs and nouns. Assessment of word-class specific deficits often relies on picture naming with different sets of images used for action and object naming. Such a setup may be problematic in neuroimaging studies, as the perception of the image and the actual differences in retrieving verbs or nouns become intertwined. To address this issue, we investigated how different sets of images affect the pattern of activation in action and object naming. In the present fMRI experiment, healthy volunteers silently performed both action and object naming from action images, and object naming from object-only images. A similar network of cortical areas was activated in all three conditions, including bilateral occipitotemporal and parietal regions, and left frontal cortex. With action images, noun retrieval enhanced activation in bilateral parietal and right frontal cortex, areas previously associated with visual search and attention. Increased activation in the left posterior parietal cortex during this condition also suggests that naming an object in the context of action emphasizes motor-based properties of objects. Action images, regardless of whether verbs or nouns were named, evoked stronger activation than object-only images in the posterior middle temporal cortex bilaterally, the left temporo-parietal junction, and the left frontal cortex, a network previously identified in processing of action knowledge. The strong influence of perceptual input on neural activation associated with noun vs. verb naming can in part explain discrepancies in previous lesion and functional neuroimaging studies on the processing of nouns and verbs.     

Migraine and genetic and acquired vasculopathies

It is remarkable that migraine is a prominent part of the phenotype of several genetic vasculopathies, including cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL), retinal vasculopathy with cerebral leukodystrophy (RVCL) and hereditary infantile hemiparessis, retinal arteriolar tortuosity and leukoencephalopahty (HIHRATL). The mechanisms by which these genetic vasculopathies give rise to migraine are still unclear. Common genetic susceptibility, increased susceptibility to cortical spreading depression (CSD) and vascular endothelial dysfunction are among the possible explanations. The relation between migraine and acquired vasculopathies such as ischaemic stroke and coronary heart disease has long been established, further supporting a role of the (cerebral) blood vessels in migraine. This review focuses on genetic and acquired vasculopathies associated with migraine. We speculate how genetic and acquired vascular mechanisms might be involved in migraine.     

权威梯度与误诊误治

同一组织内的人员之间因职称、资历、经验不同或专业差距,往往造成其在组织的中地位不同,形成所谓的"权威梯度".医院是一个合作性的工作团体,医生之间也存在较明确的资历等级关系,也不可避免地存在"权威梯度"问题.团体内有大量的信息交流的机会,位于梯度上级的权威,经验丰富,见多识广,确保了临床对疾病作出准确的判断;位于梯度下级的医生有更多的接触病人的机会,如不能把自己的意见有效地传递给位于梯度上级的医生,或上级医生对传递的信息掉以轻心,就有可能造成临床误诊误治.这就要求管理者创造一个适合意见交流的氛围,并制定制度措施,帮助医生克服"权威梯度"的负面影响,避免误诊误治.     

RN and LPN accountabilities and responsibilities

Although the scopes of practice of RNs and LPNs overlap, the main difference between the two scopes lies in the breadth and depth of the knowledge, and the clinical judgments of registered nurses. Changes in staff mix and introducing LPNs into organizations that were previously staffed only by RNs provide challenges for all care providers. Moving from all RN staffing to an RN-LPN mix requires redefining how care is delivered. Carefully planned, with an awareness of the scopes of practice and of the breadth and depth of nursing knowledge of RNs and LPNs, these changes can be accomplished with minimal conflict and disruption.     

Telemedicine and teleradiology technologies and applications

Summary. Telemedicine and teleradiology hold the key for improving future health care delivery. In this paper we first review current communication and computer technologies used in telemedicine and teleradiology. Five examples in teleradiology applications are given including hospital-integrated picture archiving and communication systems, tele-neuro-imaging, telemammography, university consortium teleradiology service, and teleradiology for second opinion. Parameters important to teleradiology applications like costs, image quality, system reliability, and turn around time are considered. Data security is discussed, including patient confidentiality and image authenticity-which will be a major issue in future teleradiology applications.