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21.
Extrapolating information from equations that govern fluid flow, a theoretical formula is developed for a sutureless cataract incision. This theoretical formula defines the resistance of aqueous outflow as a function of three variables: length of cataract incision, the length of the scleral tunnel, the tortuosity of the outflow channel, and one constant friction factor. The nonlinear relationship of corneal incisions to length, depth, and distance from the visual axis is also examined with respect to their effect on central corneal curvature and control of astigmatism. Finite element analysis of differential equations is discussed as the most plausible technique for predicting these incisional effects.  相似文献   
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The pectoralis major myocutaneous flap (PMMC flap) represents a landmark in the development of head and neck reconstructive surgery. After Stephan Ariyan first described its use for head and neck reconstruction in 1979, it has become tremendously popular and has revolutionised head and neck cancer surgery. Here, we present our initial experience with fourteen PMMC flaps in head and neck reconstruction. In most of the instances it was used for oral or oropharyngeal reconstruction. It was used for five other reconstructive tasks as well. Wound infection was the most common complication. There was no case of total flap loss. It has proven to be a reliable method of reconstuction in the head and neck.  相似文献   
23.
Characterization of an immortalized human vaginal epithelial cell line   总被引:3,自引:0,他引:3  
PURPOSE: Adherence of type 1 piliated Escherichia coli to vaginal mucosa plays a major role in the pathogenesis of ascending urinary tract infections (UTIs) in women. Progress in understanding the mechanism of adherence to the vaginal surface could be enhanced by the utilization of well-characterized vaginal epithelial cells. The objective of this study was to immortalize vaginal epithelial cells and study their bacterial adherence properties. MATERIALS AND METHODS: Primary vaginal cells were obtained from a normal post-menopausal woman, immortalized by infection with E6/E7 genes from human papillomavirus 16 (HPV 16) and cultured in serum free keratinocyte growth factor medium. RESULTS: Positive immunostaining with a pool of antibodies to cytokeratins 1, 5, 10 and 14 (K1, K5, K10 and K14) and to K13 confirmed the epithelial origin of these cells. The immortalized cells showed binding of type 1 piliated E. coli in a pili specific and mannose sensitive manner. CONCLUSION: This model system should facilitate studies on the interaction of pathogens with vaginal mucosal cells, an essential step in the progression of ascending UTIs in women.  相似文献   
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Objectives: To determine the quality of life (QOL) after stapes surgery and whether audiological parameters for hearing correlate with specific QOL factors. Design: A retrospective cross‐sectional study. Setting: A tertiary referral centre. Participants: A series of 35 patients who underwent stapes surgery of which three were excluded because they were <18 years of age, chronically or mentally ill, or in a dependant relationship. Response rate was 93% (30/32). Nine were further excluded because they had revision or bilateral surgery, or missing data. Twenty‐one patients were included in this study. Main outcome measures: The Glasgow Benefit Inventory (GBI) was used to evaluate general QOL and the Hearing Disability and Handicap Scale (HDHS) was used as a disease‐specific measure. The Belfast Rule of Thumb and Glasgow Benefit Plot assessed hearing outcomes. Results: Operative success was 86% using the Belfast Rule of Thumb and 95% had closure of the air–bone gap to within 20 dB. 81.8% of patients reported a better overall QOL as surgery. Glasgow Benefit Inventory Social and GBI Physical scores correlated positively with the HDHS speech component (P < 0.05). The duration of hearing loss correlated inversely with the average HDHS score (P < 0.05). Conclusion: The majority of patients report a better QOL as undergoing stapes surgery. Speech impacts on people's physical and social QOL of patients. Quality of life tools, in addition to objective audiologic measurements can provide clinicians with patients’ subjective perspective that helps guide clinical decision‐making and counselling.  相似文献   
25.
Extended release formulation of glipizide based on osmotic technology was developed and evaluated. The effect of different formulation variables, namely, level of solubility modifier in the core, membrane weight gain, and level of pore former in the membrane, were studied. Drug release was found to be affected by the level of solubility modifier in the core formulation. Glipizide release was inversely proportional to the membrane weight but directly related to the initial level of pore former (PVP) in the membrane. Burst strength of the exhausted shells increased with the weight gain of the membrane. On the other hand, burst strength decreased with an increase in the level of pore former in the membrane. Drug release from the developed formulations was independent of pH and agitational intensity, but dependent on the osmotic pressure of the release media. Results of SEM studies showed the formation of pores in the membrane from where the drug release occurred. The numbers of pores were directly proportional to the initial level of pore former in the membrane. The manufacturing procedure was found to be reproducible and formulations were stable after 3 months of accelerated stability studies.  相似文献   
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Bariatric surgery has been demonstrated to be an effective treatment for morbid obesity. The purpose of this study is to investigate the incidence of pre- and post-operative deep venous thrombosis (DVT) in Lap-Band surgical patients. This study group comprised 56 consecutive patients who underwent Lap-Band surgery. Mean age and body mass index were 38 years (range: 18–64 years) and 50.9 kg/m2 (range: 53–74 kg/m2), respectively. All the patients were screened with duplex ultrasonography pre- and post-operatively. There were no iliac, femoral, or popliteal vein thromboses detected at any given point of time. No patient had any clinical signs or symptoms of DVT post-operatively. There were no observable differences attributable to DVT prophylaxis. This data suggest that in the setting of chemical and mechanical prophylaxis, the incidence of DVT in patients undergoing Lap-Band surgery at an established bariatric centre is minimal.  相似文献   
28.
This article briefly outlines a collaboration among communities on Hawai‘i Island and a university-based research team to develop, implement, and evaluate a school-based substance use prevention curriculum called Ho‘ouna Pono. In addition to providing a rationale for the project, the goal of this paper is fourfold. First, an overview of the Ho‘ouna Pono research results to date (2007–2013) is provided. Second, within this overview, the ways in which selected results informed program development are highlighted. Third, the curriculum is briefly described, and finally, the role of the students and community in the video production is described.  相似文献   
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