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PURPOSE: The purpose of this article is to inform the reader of the current literature regarding nasal airflow resistance. The anatomy and physiology of nasal airflow resistance will be examined and the known effects of widening of the nasal airway upon airflow will be described. MATERIALS AND METHODS: This article is a review of the current literature regarding nasal airflow and resistance and the effects of widening of the nasal base. No patient data were collected. RESULTS: The literature shows that nasal airflow resistance can be changed by surgical manipulation and by rapid palatal expansion, but that the effects on airflow resistance and future growth and development are unpredictable. CONCLUSION: Patients with a maxilla that is constricted in the transverse dimension and nasal airflow problems may benefit from expansion of the nasal base. The resultant effects upon nasal airflow resistance and subsequent growth and development are unpredictable and therefore airflow issues alone may not be a primary reason to increase the transverse dimension of the nasal base.  相似文献   
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Levels of mRNA for the alpha 1, gamma 2 and beta 1 subunits of the GABAA receptor complex were examined in rats maintained on a chronic, continuous schedule of exposure to the benzodiazepine inverse agonist FG 7142. The effect of chronic exposure to the benzodiazepine agonist diazepam was also examined on levels of gamma 2 subunit mRNA. FG 7142 (2 mg/ml of 100% dimethyl sulfoxide (DMSO) or vehicle (100% DMSO) was administered continuously for 8 days in the right ventricle via an osmotic minipump. At the end of the eighth day of exposure, the brain was removed and cerebral cortex, cerebellum and hippocampus were dissected and mRNA prepared from each region. Levels of GABAA alpha 1 and gamma 2 subunit mRNA were examined by Northern blot analysis with cDNA probes specific for these subunits. A significant increase in alpha 1 mRNA was measured in both cortex and hippocampus, but not in cerebellum, of rats chronically exposed to FG 7142 relative to vehicle-treated rats. A significant increase in gamma 2 subunit mRNA in cortex was also evident in drug-treated rats; however, no change in gamma 2 subunit mRNA was observed in either the hippocampus or cerebellum. Examination of GABAA beta 1 subunit mRNA by solution hybridization using a beta 1 riboprobe revealed no effect of chronic FG 7142 treatment on this subunit in either cortex, hippocampus or cerebellum. In rats chronically exposed to diazepam (21 days via silastic implants), levels of gamma 2 subunit mRNA were significantly decreased in cortex, but not changed in either hippocampus or cerebellum.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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This study was undertaken to explore whether intervention withheparin and aspirin (H/A) in selected patients undergoing in-vitrofertilization (TVF) and embryo transfer could improve fecundityrates. Specifically, it explored the possibility that womendiagnosed with organic pelvic disease who demonstrated antiphospholipidantibodies (APA) could benefit from H/A administration in asimilar manner to that used in patients with recurrent pregnancyloss. We used an enzyme–linked immunosorbent assay forsix different phospholipids to identify patients who expressedAPA before they underwent IVF/embryo transfer. This study wasconfined to the first IVF/embryo transfer cycle that followedassessment of APA status and accordingly, the number of IVF/embryotransfer cycles corresponds with the number of patients treated.APA seropositive patients were treated with aspirin, 81 mg orallyq.d., and heparin 5000 IU s.c. b.i.d., beginning on day 1 ofcontrolled ovarian stimulation. The endpoint for success wasa live birth or an ultrasound confirming fetal cardiac activity(a viable pregnancy). The prevalence of APA in patients diagnosedwith organic pelvic disease (53%) was much higher than in thosewithout female pathology (14%). The administration of H/A toAPA seropositive patients significantly (P < 0.05) improvedthe viable pregnancy rate (49%) compared to the untreated APAseropositive group (16%). The viable pregnancy rate for APAseropositive women treated with H/A was also significantly (P< 0.001) higher than for untreated APA seronegative patients(27%). We conclude that all women undergoing IVF/embryo transfershould be tested for APA prior to initiating ovarian stimulation,and those with APA seropositivity should be treated with H/A.  相似文献   
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GeroScience - Apolipoprotein E (APOE) allelic variation is associated with differences in overall circulating lipids and risks of major health outcomes. Lipid profiling provides the opportunity for...  相似文献   
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