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Background  

Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo.  相似文献   
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To identify factors that influence students to choose primary care or non-primary care specialties, the authors surveyed the 509 graduating students at the Medical College of Georgia School of Medicine in 1988, 1989, and 1990. Using a Likert-type scale, the 404 responding students rated potential influences on their specialty choices from 1, very negative, to 7, very positive. The students choosing primary care specialties were positively influenced significantly more often by their desire to keep options open (85% versus 58%, p less than .001) and their desire for longitudinal patient care opportunities (95% versus 54%, p less than .001). Those choosing non-primary care specialties were more often influenced by their desire for monetary rewards (69% versus 35%, p less than .001) and by their perceptions of lifestyle following residency (74% versus 60%, p less than .01) and prestige of the specialty (57% versus 36%, p less than .001). The authors used multiple discriminant analysis to derive a discriminant function that would permit classification of students into primary care and non-primary care groups. The potential influences of desire for longitudinal care opportunities and desire for monetary rewards were statistically and clinically significant for all three years. Using the discriminant function, the authors correctly classified 81%, 79%, and 78% of the students' specialty choices for 1988, 1989, and 1990, respectively. The authors suggest that addressing the issue of monetary rewards will be necessary before the primary care fields again become attractive to students.  相似文献   
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Exertional rhabdomyolysis, a syndrome characterized by skeletal muscle degeneration and muscle enzyme leakage, has been shown to occur in normal, healthy individuals following strenuous exercise. In severe cases, this syndrome can result in renal failure and sudden death. Although anyone who performs strenuous exercise may be at risk for developing exertional rhabdomyolysis, some individuals may be more susceptible than others. A number of case reports of exertional rhabdomyolysis involve persons with sickle-cell trait, leading to the theory that these individuals might be at greater risk for developing the syndrome than those without this trait. This article discusses the etiology of exertional rhabdomyolysis, the associated risk factors for persons with sickle-cell trait, and the recommended preventive measures. Additionally, several case studies of exertional rhabdomyolysis are reviewed.  相似文献   
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Interim restorations are vulnerable to inadvertent fracture during mastication. Autopolymerizing acrylic resins have traditionally been selected for fabrication of provisional restorations. Triad light-polymerizing tooth-colored acrylic resin was recently introduced as an alternative material for this procedure. This material does not contain methyl methacrylate monomer and permits an increased working time. Heavy occlusal forces may initiate cracks within these restorations, and propagation of these cracks may ultimately lead to failure. Various forms of reinforcement fibers are available and are marketed for strengthening dental resins used for provisional restorations. Investigators have demonstrated that the mechanical properties of acrylic resins may be improved with the incorporation of reinforcing fibers, but a published evaluation of fiber-reinforced light-polymerizing provisional restorative materials is lacking. This investigation recorded and compared two mechanical properties of one light-polymerizing provisional restorative material with and without incorporation of vertically and horizontally oriented woven, matted, polyethylene fibers. No significant difference in modulus of rupture was recorded between groups with and without fibers. The mean flexural elastic modulus of the group with the horizontally oriented fibers was significantly greater than the mean flexural elastic modulus of the specimens without incorporated fibers.  相似文献   
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Eighty four out of 2151 militancy trauma patients sustained severe maxillofacial injury from Jan 1990 to March 1993. The resuscitation, stabilisation and intensive care of these patients was based on management priorities of primary resuscitation, care of airway, management of haemodynamics, oxygenation and monitoring. Anaesthesia was administered in a situation when the airway was likely to be compromised and the patients were critically sick. Initial ventilation and oxygenation was the most difficult and could be achieved with satisfactory seal around the face mask by applying water-soaked guaze pieces around the mouth and nose to “fill-in” the defects. Tracheal intubation could be accomplished with intravenous sedation by an experienced anaesthesiologist. Dental occlusion and wiring necessiated the placement of nasotracheal tube for 48-72 hours after surgery.KEY WORDS: Trauma, Maxillofacial injury, Trauma anesthesia, Anaesthesia and critical care  相似文献   
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OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants.  相似文献   
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Vasoactive intestinal peptide-secreting tumors (VIPomas) are extremely rare and difficult to diagnose. The authors describe a patient who was found to have a VIPoma after 3 years of symptoms. Somatostatin receptor scintigraphy using indium-labeled octreotide localized her tumor and prompted a surgical resection. This is the preferred imaging study for the earliest, most accurate, and cost-effective identification of VIPomas and their metastases.  相似文献   
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