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71.
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Thirty-two patients with congenital neurosensory hearing loss demonstrated dilatation of the peripheral limb of the vestibular aqueduct as visualized on pluridirectional tomograms. Multiple additional anomalies involving most frequently the cochlea (15 patients) but also the ossicles (three patients) or vestibule (one patient) were associated. The axial-pyramidal (Poschl) projection was of great value in evaluation of the vestibular aqueduct and cochlea. The technique, clinical correlation, and surgical implications are discussed. 相似文献
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74.
Most dental materials are designed to have a relatively 'neutral' existence in the mouth. It is considered that if they are 'passive' and do not react with the oral environment they will be more stable and have a greater durability. At the same time, it is hoped that our materials will be well accepted and will cause neither harm nor injury. This is an entirely negative approach to material tolerance and biocompatibility and hides the possibility that some positive gains can be achieved by using materials which behave in a more dynamic fashion in the environment in which they are placed. An example of materials which have potential for 'dynamic' behaviour exists with structures which are partly water-based or have phases or zones with significant water content and for which the water within the material can react to changes in the ambient conditions. Such materials may even be said to have the potential for 'smart' behaviour, i.e. they can react to changes in the environment to bring about advantageous changes in properties, either within the material itself or in the material-tooth complex. The controlled movement of water or aqueous media through the material may cause changes in dimensions, may be the carrier for various dissolved species, and may influence the potential for the formation of biofilms at the surface. Some of these issues may be closely interrelated. Clearly, materials which do not have the capacity for water transport or storage do not have the potential for this sort of behaviour. Some materials which are normally resistant to the healthy oral environment can undergo controlled degradation at low pH in order to release ions which may prove beneficial or protective. It is doubtful whether such behaviour should be classified as 'smart' because the material cannot readily return to its original condition when the stimulus is removed. Other materials, such as certain alloys, having no means of transporting water through their structure, can display smart behaviour by undergoing predictable changes in structure in response to applied mechanical or thermal stimuli. It has been difficult to harness such behaviour to the benefit of patients but progress in this area is slowly being made. 相似文献
75.
Shariatpanahi RE Orang F Emami SH Naimi T 《Journal of biomaterials science. Polymer edition》2006,17(6):659-667
In the field of tissue engineering, promoting cell attachment and proliferation in polymer matrices is an attractive challenge for treating patients suffering from the loss or dysfunction of tissues or organs. In this study we have investigated the effect of grafting N-vinyl-2-pyrrolidone (NVP) by gamma irradiation onto polyvinyl alcohol (PVA), a highly hydrophilic and non-toxic material. PVA scaffolds were prepared by freeze-thaw and progen (glycerol) methods. In the first method, samples were freeze-thawed for three consecutive cycles at -25 degrees C (90 min) and room temperature (60 min); in the latter, 0-40% glycerol was used as progen. Gamma irradiation of the scaffolds in the presence of NVP was performed at different concentrations (2, 3, 4 and 6%) with 5, 10 and 15 kGy 60Co. The highest percentage of grafting was obtained at 4% NVP solution and 15 kGy. Cell attachment was optimal for the scaffolds prepared using freeze-thaw and glycerol methods with 3.8% and 2.7% polyvinyl pyrrolidone (PVP), respectively. 相似文献
76.
Maj Gen PP Varma )Col TS Ramakrishnan ) Lt Col Pragnya Singh ) 《Medical Journal Armed Forces India》2011,67(1):9-14
Introduction: Chronic kidney disease (CKD) is associated with significant morbidity and mortality. Screening and detection of early stages of CKD can help institute interventions that may delay the progression of the disease. One aim was to study the prevalence of early stages of CKD in the Army.Methods: A cross-sectional study ofArmy Personnel in an Army cantt in Central India was carried out. All participants filled a structured questionnaire and anthropometric data was collected. Investigative profile included routine urine exam, semi-quantitative microalbuminuria (MAU), serum creatinine, lipid profile and fasting blood glucose. Glomerular Filteration rate (eGFR) was calculated using the Modification of Diet in Renal Diseases (MDRD) study equation.Result: A total of 1920 subjects were examined with 731 (38.07%) from Arms and 1189 (6I.93%) from Services. 348 were excluded and of the remaining 1572 subjects, 141 (8.97%) had MAU and 157 (9.99%) had deranged Albumin Creatinine Ratio (ACR). Mean eGFR by MDRD equation was 102 ± 25.84 ml/min/1.73m2. Early CKD was seen in 150 (9.54%) with 84 (5.34%) in stage I CKD, 55 (3.5%) in stage II and 11 (0.7%) in stage III. Multiple logistic regression showed BMI > 23, the presence of DM and HTN were independent risk factors for CKD.Conclusion: 9.54 % of healthy army personnel were found to have early stages of CKD. Institution of screening programs can result in early detection of CKD. 相似文献
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78.
This prospective study analyzes the neonatal outcome in deliveries complicated by meconium stained amniotic fluid. In a study of 1000 live born deliveries, meconium staining of amniotic fluid was seen in 50 (5%) deliveries. Out of these, 20 newborns (40%) developed classical signs of meconium aspiration syndrome and were managed according to a predetermined protocol. Multiparity, term deliveries, use of sedatives in mother, intrauterine growth retardation and prolonged labour were some of the risk factors for development of meconium aspiration syndrome in newborns. This study highlights the need for review of management protocol in newborns after meconium staining of the amniotic fluid, including the use of prophylactic antibiotics.KEY WORDS: Amniotic fluid, Delivery, Meconium aspiration, Respiratory distress syndrome 相似文献
79.
Sixteen strains of Vibrio cholerae were isolated from cases of diarrhoea. Out of these, 12 (75%) were identified as Vibrio cholerae 0139 synonym Bengal and 4 (25%) as Vibrio cholerae El Tor by standard biochemical and serological tests. Modified CAMP reaction in sheep blood agar showed that 0139 produced moderate hemolysis, El Tor produced wider zone of hemolysis whereas Classical Vibrio cholerae produced no zone of hemolysis (CAMP negative). Break point minimum inhibitory concentration (MIC) by agar dilution method showed that all 0139 strains were resistant to ampicillin 8 mg/L, streptomycin 1 mg/L, chloramphenicol 8 mg/L, sulphamethoxazole 32 mg/L and trimethoprim 0.3-128 mg/L, 58.3% were sensitive to gentamicin 1 mg/L, and all were sensitive to norfloxacin 1 mg/L and cefotaxime 1 mg/L. Resistance to trimethoprim, sulphamethoxazole, ampicillin and gentamicin in 5 strains could be transferred to E coli K-12 by conjugation experiment at a rate of 5×10−6 to 4×10−3. Distinct plasmid bands of 35.8 mega daltons could be seen in agarose gel electrophoresis.KEY WORDS: CAMP test, Drug resistance, Plasmid, Vibrio cholerae 0139. 相似文献
80.