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1.
We investigated the timing of podofilox delivery to see how it correlated with papilloma size. We looked at times ranging from once per week (morning and afternoon) to five times per week (morning and afternoon). We also looked at delivery systems that might enhance the effectiveness of the drug by increasing penetration of the overlying cutaneous horn. These included soaking prior to drug administration, the use of a grooved needle subsequent to drug administration, and the various possible combinations of these techniques. We found that the timing of treatments had relatively little effect on the size of the papillomas. For example, at the end of ten weeks, the geometric mean diameter (GMD) (mm) of the papillomas treated five times per week and induced by a 10(-1) dilution of the virus (group B) was 18. Likewise the GMD (mm) of papillomas treated once per week was 18 (group D). On the other hand, we found that soaking plus the use of a grooved needle plus podofilox resulted in the curing of all lesions induced by a 10(-2) virus dilution and of most induced by the 10(-1) dilution, whereas soak plus podofilox or podofilox alone were not as effective in curing the lesions. Podofilox plus needle approached the soak plus podofilox plus needle in effectiveness. Treatment schedule was not a critical determinant of podofilox effectiveness. Therapeutic benefits were enhanced by hydration of the overlying cutaneous horn and penetration with a grooved needle.  相似文献   
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Spontaneous resolution of deformities after excision of facial skin lesions has been known and used for a long time by plastic surgeons. The resorption mechanism of deformity is based on natural skin expansion, and seems to be directly related to the action of the muscles of facial expression and their skin relations. Natural expansion has been shown to be effective in children. Between 1990 and 1994 excision of skin lesions, including congenital nevi, leading to postoperative deformity of the cheek, labial commissure, nose, eyelid and forehead, was performed on 35 patients, aged from 3 month to 12 years. The average follow-up is 24 months. For 26 patients (74%), natural resorption was observed 4 or 6 weeks later with good aesthetic results. For 6 patients (17%), the deformity persisted 3 or 6 months later, but did not require any further surgery. For 3 patients (9%), a second operation was necessary. Using the skins natural capacity for expansion in the treatment of facial skin defects in children is a method of reconstruction which has already been used for excision in enforced position. The platysma and muscles of facial expression by their action on skin mobilisation, allow natural expansion. A better knowledge of cutaneous biomechanical properties enables plastic surgeons to find an alternative to other classical methods.  相似文献   
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Fibrous dysplasia is an abnormal fibroosseous process of bone of unknown cause. The incidence of skull involvement varies, painless enlargement being the most common presenting symptom. Change in vision is a rare but recognized finding. We report a 3-year-old boy with extreme fibrous dysplasia involving the skull base, who presented with blindness. He underwent exposure osteotomies of the frontal bones and orbits to provide access for skull base tumor removal. The orbital roofs were reconstructed with microplate-fixed cranial grafts. One and one half years after tumor excision followed by immediate reconstruction, the boy retains facial symmetry, and his ocular function has not deteriorated.  相似文献   
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Sensory activity mediates regulation of tyrosine hydroxylase (TH), the first enzyme in the dopamine biosynthetic pathway, in the rodent olfactory bulb. The current studies established for the first time primary cultures of neonatal mouse olfactory bulb expressing TH and tested whether L-type calcium channels mediate the activity-dependent regulation of the dopamine phenotype. After 1 d in vitro (DIV), a small population of TH-immunostained neurons that lacked extensive processes could be demonstrated. After an additional 2 DIV in serum-free medium, the number of TH neurons had doubled, and they exhibited long interdigitating processes. Membrane depolarization for 48 hr with 50 mM KCl produced a further 2.4-fold increase in the number of TH-immunoreactive neurons compared with control cultures. Increased TH neuron number required at least 36 hr of exposure to KCl. Forskolin, which increases intracellular cAMP levels, induced a 1.5- to 1.6-fold increase in the number of TH-immunostained neurons. Combined treatment with KCl and forskolin was not additive. Nifedipine, an L-type calcium channel blocker, completely prevented the depolarization-mediated increase in TH expression but did not block the response to forskolin. Treatment with Bay K8644, an L-type calcium channel agonist, also significantly increased the number of TH-expressing neurons. Depolarization also induced alterations in neuritic outgrowth, resulting in a stellate versus an elongate morphology that, in contrast, was not prevented by nifedipine. These results are the first demonstration that in vitro, as in vivo, depolarization increases TH expression in olfactory bulb and that L-type calcium channels mediate this activity-dependent regulation of the dopamine phenotype.  相似文献   
7.
Horseradish peroxidase (HRP) is well known for mediating the electron-transfer oxidation of electron-rich aromatic 'donors' such as phenols and anilines, but has not been described to oxidize aliphatic amines. We here confirm the inability of HRP to oxidize typical aliphatic amines, even those which would exist significantly as free bases at the operative pH. In contrast, trans-2-phenylcyclopropylamine (2-PCPA) is both a substrate (turnover product is cinnamaldehyde) and a time-dependent inactivator of HRP. These activities of 2-PCPA are consistent with either a concerted or rapid sequential one-electron-oxidation/ring-opening to give an intermediate capable of covalent binding to the enzyme. 2-PCPA is the first known example of a simple aliphatic amine which serves as a substrate for HRP under turnover conditions.  相似文献   
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PURPOSE: To examine the feasibility and reliability of ratings completed by hospital-based registered nurses of the humanistic qualities, communication skills, and selected aspects of the clinical skills of practicing internists. METHOD: In 1988-1989, registered nurses who worked in the same 175 hospitals as 232 internists with admitting privileges at these hospitals rated the internists' performances. The nurses were selected from medicine floors, specialty floors, and intensive care units and/or critical care units, using lists provided by head nurses. A total of 1,877 rating questionnaires with 13 performance categories were collected (with a mean of 8.01 nurses per internist). The ratings were analyzed to determine measurement characteristics and the relationships of the nurses' demographic characteristics to the ratings. In addition, for each of ten performance categories for 152 of the internists, the average rating each internist received from nurses was compared with the average rating each internist received from peer physicians. Statistical analysis used Pearson correlations, canonical correlations, factor analyses, Student's t-tests, analysis of variance, and stepwise multiple regression. Finally, the internists themselves, including physicians who were not actually rated by the nurses, were asked to complete a brief questionnaire that included questions about their opinions of the use of nurses' ratings. RESULTS: The nurses' ratings correlated moderately strongly with the peer physicians' ratings and had a common structure. However, the nurses' ratings were lower for several humanistic qualities, including respect, integrity, and responsibility, and their ratings were higher for medical knowledge and verbal communications. Across the 13 performance categories, approximately 10-15 ratings from nurses were needed to obtain a reliable assessment of an internist's humanistic qualities and communication skills. Many internists felt that nurses' ratings should be used equally with, or at least as a lesser contribution to, ratings by peer physicians of humanistic qualities and communication skills. CONCLUSION: Nurses' ratings appear to provide a feasible and reliable method of evaluating the internists' communication skills and humanistic qualities, when used in conjunction with ratings by peer physicians.  相似文献   
9.
Structural engineers use design codes formulated to consider uncertainty for both reinforced concrete and structural steel design. For a simple one-bay structural steel frame, we survey typical uncertainties and compute an interval solution for displacements and forces. The naive solutions have large over-estimations, so we explore the Mullen-Muhanna assembly strategy, scaling, and constraint propagation to achieve tight enclosures of the true ranges for displacements and forces in a fraction of the CPU time typically used for simulations. That we compute tight enclosures, even for large parameter uncertainties used in practice, suggests the promise of interval methods for much larger structures.  相似文献   
10.
Prevalence rates of trauma and posttraumatic stress disorder (PTSD) were estimated from a probability sample of 2,509 adults from 4 cities in Mexico. PTSD was assessed according to Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) criteria using the Composite International Diagnostic Interview (CIDI; WHO, 1997). Lifetime prevalence of exposure and PTSD were 76% and 11.2%, respectively. Risk for PTSD was highest in Oaxaca (the poorest city), persons of lower socioeconomic status, and women. Conditional risk for PTSD was highest following sexual violence, but nonsexual violence and traumatic bereavement had greater overall impact because of their frequency. Of lifetime cases, 62% became chronic; only 42% received medical or professional care. The research demonstrates the importance of expanding the epidemiologic research base on trauma to include developing countries around the world. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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