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The Deans' Rural Primary Care Clerkship was developed through the collaborative efforts of South Carolina's two medical schools. The clerkship provides students an innovative learning experience in rural community medicine through the unique combination of learning opportunities with community-oriented primary care, continuous quality improvement, interdisciplinary health care teams, and cultural competency. Much of students' learning addresses current directives for population health training. The positive experience students are having in these rural, underserved South Carolina communities will help them better understand the rewards and challenges of rural, community-responsive health care.

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In June 2000, the Telemedicine Center at the Brody School of Medicine, East Carolina University in Greenville, NC participated in a simulated disaster response in Pu'u Paa, Hawaii, a lava plain without running water, electricity, or human habitation. During the five-day exercise we evaluated the ability to establish telecommunications and the effectiveness of the infrastructure, services, and applications implemented for an operational global emergency response. Scaleable technologies were configured and systematically tested to determine the ability to provide medical and health care in an austere environment. A medical communications matrix was constructed and used throughout the evaluation. Results show that telemedicine can be an important contribution to humanitarian relief efforts and medical support following disasters. Additional research is needed to build upon the lessons learned from participation in this exercise.

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BACKGROUND: Real-time interactive teleconference clinical consultations are envisioned for increasing accessibility to medical care by patients whose demographics restrict care. There are no published studies, however, describing referrals and the referring practitioners, patients, and specialists participating in these consultations. OBJECTIVE: To assess characteristics of participants of interactive teleconference clinical consultations. DESIGN: Descriptive study, February 1, 1996, through April 30, 1999. SETTING: Eastern North Carolina: Brody School of Medicine at East Carolina University and 7 rural hospitals and clinics in its telemedicine network. SUBJECTS: Rural practitioners requesting consultations (n = 76), consulting physicians (n = 40), and patients completing evaluations following consultations (n = 495). MAIN OUTCOME MEASURES: Demographic and descriptive variables for referring providers, patients, and consulting physicians relative to the population in the region and to patients and physicians at the East Carolina University School of Medicine clinics. RESULTS: The largest number of referrals (65.2%) were made to obtain a second opinion or recommend a management plan in dermatology (33.5%), allergy (21.0%), or cardiology (17.8%). Significant patient characteristics were race (56.8% minorities), age (19.6% < or = 10 years old and 26.0% > or = 59.0 years old), sex (59% females), and insurance status (10.7% no insurance, 33.7% Medicaid, 15.4% Medicare). In addition, 38.0% had household incomes below the poverty level. Only 5.2% of the patients would have been treated by the referral practitioner, making travel necessary for consultation. Demographic characteristics of the practitioners were not statistically different. CONCLUSIONS: Participants of interactive teleconference clinical consultations are patients whose access to medical care might otherwise be limited. Use of telemedicine by practitioners is not related to age or sex. Arch Fam Med. 2000;9:1036-1040

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There are a number of different quantitative models that can be used in a medical diagnostic decision support system (MDSS) including parametric methods (linear discriminant analysis or logistic regression), non-parametric models (K nearest neighbor, or kernel density) and several neural network models. The complexity of the diagnostic task is thought to be one of the prime determinants of model selection. Unfortunately, there is no theory available to guide model selection. Practitioners are left to either choose a favorite model or to test a small subset using cross validation methods. This paper illustrates the use of a self-organizing map (SOM) to guide model selection for a breast cancer MDSS. The topological ordering properties of the SOM are used to define targets for an ideal accuracy level similar to a Bayes optimal level. These targets can then be used in model selection, variable reduction, parameter determination, and to assess the adequacy of the clinical measurement system. These ideas are applied to a successful model selection for a real-world breast cancer database. Diagnostic accuracy results are reported for individual models, for ensembles of neural networks, and for stacked predictors.

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A number of quantitative models including linear discriminant analysis, logistic regression, k nearest neighbor, kernel density, recursive partitioning, and neural networks are being used in medical diagnostic support systems to assist human decision-makers in disease diagnosis. This research investigates the decision accuracy of neural network models for the differential diagnosis of six erythematous-squamous diseases. Conditions where a hierarchical neural network model can increase diagnostic accuracy by partitioning the decision domain into subtasks that are easier to learn are specifically addressed. Self-organizing maps (SOM) are used to portray the 34 feature variables in a two dimensional plot that maintains topological ordering. The SOM identifies five inconsistent cases that are likely sources of error for the quantitative decision models; the lower bound for the diagnostic decision error based on five errors is 0.0140. The traditional application of the quantitative models cited above results in diagnostic error levels substantially greater than this target level. A two-stage hierarchical neural network is designed by combining a multilayer perceptron first stage and a mixture-of-experts second stage. The second stage mixture-of-experts neural network learns a subtask of the diagnostic decision, the discrimination between seborrheic dermatitis and pityriasis rosea. The diagnostic accuracy of the two stage neural network approaches the target performance established from the SOM with an error rate of 0.0159.

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The less common methods of medication administration that used to be used only in the hospital are also now used in alternate settings. Understanding the treatment modalities, care requirements, and complications of these alternate routes of administration is important for nurses who participate in the care of patients receiving infusions. Several alternate routes of administration are discussed, with emphasis on the more commonly used methods: intra-arterial, intraspinal, intraventricular, intraperitoneal, intraosseous, and several other routes.

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This article provides an overview of the physician assistant profession in general and in South Carolina. Information on the educational program at the Medical University of South Carolina and the results of a study of the satisfaction and contribution of the physician assistant as perceived by a sample of South Carolina supervising physicians is included. The study demonstrates that the physician assistant makes an important contribution to health care in South Carolina.

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The rotation of the maxillary molars is considered important in the orthodontic treatment of malocclusions. In this study, a computer analysis program was developed to examine the rotations of maxillary molars, mandibular molars, and maxillary first premolars in casts of permanent dentitions with acceptable occlusions. Ninety-three sets of untreated 'acceptable occlusion' models from the collection of the Foundation for Orthodontic Research (FOR) were scanned on a flat bed scanner. The images were analysed using custom software. Measurements were made by relating maxillary first permanent molars to the midline, archform, opposite canine, and mandibular first permanent molars. The mandibular first molars and maxillary first premolars were also analysed and their rotations measured. The mean rotations of the maxillary first molars, measured as the angle between a line joining the tips of the buccal cusps and a line tangent to the appropriate archwire form (from Ricketts' Pentamorphic Arches) at the first molars, were 0.59 and -0.72 degree (positive values represent mesio-lingual rotations) for the right and left, respectively. For the mandibular molars, these means were 6.34 and 8.40 degrees, respectively. The mean differences in rotation between buccal cusp tips of maxillary and mandibular first molars in occlusion were 5.75 and 9.12 degrees for the right and left, respectively, with the mandibular being more mesio-lingually rotated. The differences between left and right were significant for all measurements. The present study brings into question the suitability of our present "straight wire" prescriptions in producing similar occlusions. It also suggests that scanning models for computer analysis may be a practical and precise way to measure similar rotations in untreated normal and treated occlusions.

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The nature of the American health care marketplace is in a state of flux and refinement. The recent attempt by the federal government to change the health care system has brought these issues to the forefront of public and private discourse. This research endeavor examines if these discussions influenced health care decisions by some of the nation's most influential decision makers.

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The purpose of the present investigation was to determine the effectiveness of the Myo in reducing plaque and gingivitis development in orthodontic patients using a single-blind, cross-over design. Thirty subjects were randomly assigned to experimental and control groups. All subjects continued their customary oral hygiene procedures. In addition, the experimental group was instructed to chew on the Myo for four minutes, twice each day. Plaque Index and Gingivitis Index were assessed each time the subjects attended their scheduled orthodontic appointment. The patients failed to demonstrate any significant reduction in plaque and gingivitis development when the Myo was introduced as an additional oral hygiene measure. Some soft tissue injuries were found.

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The clinical manifestations of gonadotroph adenomas are almost always neurological, consequences of their large size, and are rarely endocrinological. We report an exception, a 39-yr-old woman whose gonadotroph adenoma caused supranormal serum concentrations of FSH, which resulted in the development of multiple ovarian cysts, persistent elevation of her serum estradiol concentration, and endometrial hyperplasia. She initially presented because of amenorrhea at age 30 yr and was treated for an intrasellar mass by transsphenoidal surgery at age 31 yr and again at age 36 yr. Before and after the second operation she had persistently supranormal plasma estradiol concentrations (> 1840 pmol/L) and endometrial hyperplasia. When she was evaluated at age 39 yr, transvaginal ultrasound showed multiple ovarian cysts and endometrial thickening. Her plasma estradiol level was markedly supranormal (2160 pmol/L), FSH was mildly supranormal (17.8 IU/L), and alpha-subunit was markedly supranormal (23.3 micrograms/L). Characteristic of gonadotroph adenomas, her LH beta level increased by 69% in response to TRH. Neither FSH nor alpha-subunit decreased in response to administration of the GnRH antagonist, Nal-Glu-GnRH (5 mg/12 h for 4 weeks). Excised adenoma tissue exhibited morphological features of a gonadotroph adenoma. This patient appears to be unique, in that her gonadotroph adenoma caused slightly, but persistently, supranormal concentrations of FSH, which caused ovarian stimulation, including supranormal plasma estradiol concentrations, multiple ovarian cysts, and endometrial hyperplasia. We propose that gonadotroph adenomas be considered in the differential diagnosis of patients who have this constellation of abnormalities.

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The chemical composition, thermal behaviour and mechanical properties of three tooth positioner materials, Urethane P1 (P1), White Rubber (WR) and Elastocryl (EL) were investigated. Infra-red spectrophotometry indicated the P1 polyurethane material to be of the polyether type, and EL to be a blend of poly(ethyl methacrylate) and poly(methyl methacrylate) while WR appeared to be filled cis-poly (isoprene) (natural rubber). The glass transition temperature (Tg) for EL was determined as approximately 10 degrees C, and for both P1 and WR the Tg was less than -50 degrees C. The stress relaxation behaviour was assessed in compression by measuring the stress variation with time. The results for all three materials conformed to the superelastic theory of rubber elasticity. EL exhibited both a more rapid rate and higher degree of stress relaxation than did P1 and WR. Recovery from deformation was assessed by compressing cylinders for given periods of time and then measuring the level of reduced residual strain of the material with time. All three materials exhibited significant residual strain (epsilon(t)) over 'clinically relevant' time periods, and the reduced residual strain (epsilon(t)/epsilon(O)) following deformation was greater for EL than P1 or WR. There was some indication that the three materials have some permanent set following deformation. It was concluded that, in considering desirable mechanical properties of tooth positioner materials, EL is the least suitable of the three examined, with none of the materials being ideal.

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Most previous studies of archwire deformation over time (hereafter referred to as "time-dependent deformation of orthodontic wires") have been conducted at a constant room temperature. In the clinical situation however, arch wires are exposed to 37 degrees C as well as to periods of temperature increase when hot foods or fluids are ingested. The effects of the latter on time-dependent behaviour are largely unknown. Since the introduction of direct electric resistance heat treatment to superelastic nickel titanium wires, there have been no reports on its effect on time-dependent deformation. This study investigated the effects of repeated temperature increases (70 degrees C) on stainless steel, nickel titanium and beta titanium wires. The wires were deflected by approximately 3 and 5 mm on two jigs for periods of 1 minute, 1, 7, 14 and 28 days. Permanent deformation was measured optically with a measuring microscope and the amount of time-dependent deformation was calculated. Beta titanium wires demonstrated the greatest amount of time-dependent deformation; followed by non-superelastic nickel titanium, stainless steel, and superelastic nickel titanium. Exposure to repeated temperature (70 degrees C) increases and direct electric resistance heat treatment of superelastic nickel titanium did not affect time-dependent behaviour.

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Limited published research on friction deals mainly with conventional stainless steel brackets and arch wires. However, the clinician can choose from a range of modern materials in determining arch wire and bracket combinations. This study quantifies the dynamic frictional force of sliding between different modern orthodontic brackets and arch wires. From the multitude of factors involved in the frictional process, the following were selected for investigation: arch wire material, bracket material, bracket-to-arch wire angulation, and lubrication (artificial saliva). The frictional force involved in sliding a ligated arch wire through a bracket slot was measured with a universal materials testing machine. A four-way analysis of variance was used to assess the results. Of the four factors investigated, all were found to have a significant influence on friction. Polycarbonate brackets showed the highest friction and stainless steel brackets the lowest. Friction increased with bracket-to-arch wire angulation. Lubrication significantly reduced friction. A range of 0.9 to 6.8 N frictional force was recorded. The actual force values recorded were most useful for comparing the relative influence of the factors tested on friction, rather than as a quantitative assessment of friction in vivo. The forces observed suggest that friction may be a significant influence on the amount of applied force required to move a tooth in the mouth. Hence, arch wire and bracket selection may be an important consideration when posterior anchorage is critical.

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This article describes a model used to train radiology staff in customer service relations at a large southeastern medical center. Information about the needs of the radiology department and staff was acquired through quantitative and qualitative assessments. The primary goal of the training was twofold: 1) to develop employee awareness of customer expectations and 2) to develop problem-solving skills to respond to customer service related issues. Instructional methods compatible with adult learning were used and training results were assessed. Positive changes in employee attitudes and behaviors are described and recommendations for training development and implementation are discussed.

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Consideration of facial type plays an important role in the formulation of an orthodontic treatment plan and prognosis of treatment. Of particular importance is the vertical relationship, that is, whether an individual is long-faced (dolichofacial), or short-faced (brachyfacial). The vertical facial type provides a clue regarding the growth direction of the facial complex, and should be used with an anteroposterior classification to describe a patient's face. The potential for confusion in communicating vertical facial types exists due to the nature of the terminology in use. For example, the term dolichoprosopic as used in the Bimler analysis has an opposite meaning to the term dolichofacial. It would seem prudent that if such terminology is to be employed there should be some attempt at standardization, and at least an appreciation of the derivations of the terms, and their differences.

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