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91.
S Vaidyanathan BM Soni L Gopalan P Sett JW Watt G Singh J Bingley P Mansour KR Krishnan T Oo 《Canadian Metallurgical Quarterly》1998,36(12):838-846
Patients with chronic tetraplegia are prone to develop unique clinical problems which require readmission to specialised centres where the health professionals are trained specifically to diagnose, and treat the diseases afflicting this group of patients. An appraisal of the readmission pattern of tetraplegic patients will provide the necessary data for planning allocation of beds for treatment of chronic tetraplegic patients. Hospital records of patients with tetraplegia readmitted to the Regional Spinal Injuries Centre, Southport, UK between 1 January 1994 and 31 December 1995 were analyzed to find out the number of tetraplegic patients who required readmission, reasons for readmission, duration of hospital stay, and mortality among patients readmitted. During the 2-year period, 155 tetraplegic patients were readmitted and 44 of them (28.4%) required more than one readmission (total readmission episodes: 221); these patients occupied 4.5 beds which is equivalent to 11.5% of the total bed capacity of the spinal unit. Among the reasons for the readmissions, evaluation and care of urinary tract disorders topped the list with 96 readmission episodes (43.43%) involving 70 patients; the median hospital stay was 3 days, and 18 patients (26%) required more than one readmission during this period. One hospital bed was occupied by the tetraplegic patients requiring treatment/evaluation of urinary tract disorders. Assessment and treatment of cardio-respiratory diseases was the second most common reason for readmission with 51 readmission episodes pertaining to 27 patients having a median hospital stay of 6 days; 13 patients (48%) were readmitted more than once within this 2-year period. Treatment of cardio-respiratory diseases in chronic tetraplegic patients required 1.2 hospital beds yearly. Only five tetraplegic patients were readmitted for treatment of pressure sore(s); however they had a prolonged hospital stay (median duration: 101 days). Social reasons accounted for 13 readmission episodes concerning nine patients who stayed in the hospital for varying periods (median: 6.5 days; mean: 35 days). Four tetraplegic patients readmitted with acute chest infection expired. An 81 year-old tetraplegic died of myocardial infarction. Urinary sepsis, renal insufficiency, respiratory failure and intra-cerebral haemorrhage accounted for the demise of a 41 year-old tetraplegic patient following surgical removal of a large, impacted stone at the pelviureteric junction. A tetraplegic patient who was admitted with haematuria subsequently underwent cystectomy for squamous cell carcinoma of the urinary bladder; he developed secondaries and expired 5 months later. As more patients with high cervical spinal cord injury survive the initial period of trauma, and as the life expectancy of tetraplegic patients increases, it is likely that greater numbers of tetraplegic patients will be requiring readmission to spinal injuries centre. Although it may be possible to prevent some of the complications of spinal cord injury and hence the need for a readmission, progress in medicine and rehabilitation technology will create additional demands for readmissions of chronic tetraplegic patients in order to implement the newer therapeutic strategies. Thus a change in the pattern of readmission of chronic tetraplegic patients is likely to be the future trend and this should be taken into account while making plans for providing the optimum care to chronic tetraplegic patients. 相似文献
92.
AM Mansour 《Canadian Metallurgical Quarterly》1998,81(5):958-962
The permeability to several chemical compounds and the histology of vaginal and buccal mucosa are very similar. Because vaginal mucosa is more abundant, it may be used as a model for the latter. To further develop the vaginal/buccal mucosa model, the objective of the present study was to evaluate the passage of a small polypeptide, vasopressin, across fresh and frozen specimens of these two mucosae. Specimens of fresh buccal and vaginal mucosa were taken from excised tissue obtained following vaginal hysterectomies and various oral surgical procedures. Pieces of buccal and vaginal tissue specimens obtained were used fresh or were snap-frozen and stored at -85 degrees C for periods of up to 10 months. Biopsies from fresh and thawed specimens were mounted in flow-through diffusion cells and their permeability to tritiated vasopressin was determined using a continuous flow-through perfusion system. Specimens were examined histologically before and after freezing as well as before and after permeability experiments and similarities between vaginal and buccal tissues verified. No statistically significant differences between flux values for fresh and frozen vaginal and buccal mucosa, respectively, were found. These results demonstrate that the permeation of vasopressin across fresh and frozen human vaginal and buccal mucosa is for practical purposes similar. These results further support the human vaginal/buccal mucosa model for in vitro permeability studies on therapeutically active compounds. 相似文献
93.
R. B. Mansour 《国际能源研究杂志》2004,28(9):817-832
A multiphase, multimode heat transfer numerical model was used to estimate the maximum skin temperature of a stagnant water‐filled pipe structure subject to an intense flame. This transient two‐dimensional mathematical model takes into account conduction, convection and radiation as well as evaporation of cooling water. Results have been obtained based on practical data and experimental field findings. The cooling water film that surrounds the pipe structure attacked by the flames, can originate from fire‐fighting water hoses or from a sprinkler water system. Two different values of water film thickness of 3 and 5 mm are analysed. The simulation results indicate that the main parameter which controls the pipe skin temperature, is the water film thickness covering the pipe. Indeed the maximum steel pipe skin temperature drops from 175.5 to 108.8°C when the water film thickness is increased from 3 to 5 mm for the 20 inch‐water‐filled pipes. However the water presence inside the pipe has negligible effect on the pipe skin temperature. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
94.
In this paper, we present a method for designing temperature-compensated cavity resonators using shape memory alloys (SMAs). This paper gives an expression for the temperature drift of resonant frequency, which is valid for any conductor-loaded cavity regardless of its shape. This formula, combined with a field perturbation model, is used to derive the resonant frequency of an SMA-compensated resonator subject to temperature fluctuation. Experimental results are given that confirm the feasibility of the proposed design approach. A design method is proposed for specifying SMA alloys to build the actuator. An expression is derived to accurately predict the performance of an actuator design. 相似文献
95.
Dispersed oil was separated from oil–water emulsions in an electroflotation cell equipped with insoluble electrodes: titanium coated with ruthenium oxide as anode and stainless steel screen as cathode. The effect of operating parameters such as current density, oil concentration, flotation time and coagulant concentration, on the performance of the electroflotation cell was examined. Oil removal reached 70% at optimum conditions; 75% in the presence of NaCl (3.5% by wt); and 99.5% in the presence of both NaCl and an optimum concentration of coagulant. Electrical energy consumption varied from 0.4 to 1.6 kWh m−3 according to experimental conditions. The performance of the oil removal process was also represented by a first order kinetic rate model. The constants obtained fit the experimental data well. Good correlation was found for the change in percentage oil removal within a wide range of operating parameters. 相似文献
96.
PURPOSE: To evaluate the long-term results of balloon dacryocystoplasty in the treatment of epiphora due to obstruction of the nasolacrimal ducts. MATERIALS AND METHODS: One hundred eyes in 84 patients with complete or incomplete obstruction of the lacrimal sac and duct were selected for dacryocystoplasty. A catheter with a balloon diameter of 3 mm was used. Follow-up was 5-48 months. No stents were placed. A Kaplan-Meier analysis was used to evaluate patency. RESULTS: The long-term primary patency rate was 70% +/- 7 (+/- standard error). Repeat dacryocystoplasty was successful in 10 of the 11 cases with initial failure or reobstruction during follow-up, which yielded a long-term secondary patency rate of 81% +/- 7. There was no association between the length of the obstruction or the duration of symptoms before dacryocystoplasty and the initial and long-term success. Initial and long-term success was statistically significantly higher in dacryocystoplasty for an incomplete obstruction rather than for a complete obstruction. CONCLUSION: The long-term results of dacryocystoplasty, followed if necessary by repeat dacryocystoplasty, are good. Dacryocystoplasty is a safe and simple procedure and could become the treatment of choice for epiphora due to obstruction of the nasolacrimal ducts. Dacryocystorhinostomy is indicated when dacryocystoplasty or repeat dacryocystoplasty fails or when dacryocystoplasty is contraindicated (e.g., in anatomic malformations in the lacrimal duct or bony canal). 相似文献
97.
In this study the concentration and chemical potential of oxygen in liquid Co-Ni alloys equilibrated with cobalt-nickel aluminate spinel solid solutions and alumina have been determined at 1773, 1823 and 1873K as a function of nickel concentration. The oxygen content of the melt has been measured by suction sampling and inert gas fusion analysis. The corresponding oxygen potential has been determined with the following solid state cell: Mo, Mo+MoO2 | (MgO)ZrO2 | (Co, Ni) melt + AI2O3 + (Co, Ni)O·(1+x)Al2O3, Mo. The effect of nickel on the activity coefficient of oxygen in Co-Ni alloys has been determined. The results for the activity coefficient have been modelled with Wagner's interaction parameters and also the more recent exponential method of St. Pierre et al. at the three temperatures. 相似文献
98.
C Kwok PA Weller S Guioli JW Foster S Mansour O Zuffardi HH Punnett MA Dominguez-Steglich JD Brook ID Young 《Canadian Metallurgical Quarterly》1995,57(5):1028-1036
Campomelic dysplasia (CD) is a skeletal malformation syndrome frequently accompanied by 46,XY sex reversal. A mutation-screening strategy using SSCP was employed to identify mutations in SOX9, the chromosome 17q24 gene responsible for CD and autosomal sex reversal in man. We have screened seven CD patients with no cytologically detectable chromosomal aberrations and two CD patients with chromosome 17 rearrangements for mutations in the entire open reading frame of SOX9. Five different mutations have been identified in six CD patients: two missense mutations in the SOX9 putative DNA binding domain (high mobility group, or HMG, box); three frameshift mutations and a splice-acceptor mutation. An identical frameshift mutation is found in two unrelated 46,XY patients, one exhibiting a male phenotype and the other displaying a female phenotype (XY sex reversal). All mutations found affect a single allele, which is consistent with a dominant mode of inheritance. No mutations were found in the SOX9 open reading frame of two patients with chromosome 17q rearrangements, suggesting that the translocations affect SOX9 expression. These findings are consistent with the hypothesis that CD results from haploinsufficiency of SOX9. 相似文献
99.
The authors demonstrate relationships between two different stability criteria, including reduced-order versions of these criteria. Modifications of the criteria can also be used for root counting. The various matrices whose signatures are the key to obtaining root distributions are related by congruency transformations with triangular structure, implying that the sign patterns of the leading principal minors are identical 相似文献
100.
A new method is presented for reconstructing smooth refractive index profiles of optical waveguides from measured effective indexes. It is based on the semivectorial finite difference method to solve the polarized wave equation for a given refractive index profile. An iterative simplex algorithm is used to find the best refractive index parameters that give, as a solution, effective indexes close to the measured ones. The method is applied successfully to Ag+-Na + ion-exchanged glass slab waveguides and to diffused Mg/Ti:LiNbO3 slab waveguides. Dopant concentration profiles are obtained by using secondary ion mass spectrometry. The relationship between the refractive index change and the dopant concentration is determined for both cases. The iterative simplex algorithm-finite difference method (ISA-FDM) is compared to other index profile reconstruction methods, and the advantages with respect to WKB-based methods are pointed out 相似文献