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81.
Development and evaluation of a new composite Laserskin graft 总被引:5,自引:0,他引:5
BACKGROUND: Tremendous effort has been made to improve the graft take rate of cultured epidermal autograph. The purpose of this study is to develop and evaluate a new composite Laserskin graft (CLSG) as a human skin substitute for wound resurfacing. METHODS: The seeding efficacy of cultured keratinocytes on plain Laserskin was compared with the 3T3 cell-seeded Laserskin and allogenic fibroblast-populated Laserskin. Three different types of CLSG, 2 cm in diameter each, were prepared and tested in rats. Type A CLSG consisted of proliferative allogenic rat fibroblasts on both sides of the Laserskin with autologous keratinocytes also on the upper side. Fibroblasts and keratinocytes were seeded only on the upper side of the Laserskin in type B CLSG. Keratinocytes alone were seeded on plain Laserskin in type C CLSG. Type B CLSG consisting of autologous keratinocytes and autologous dermal fibroblasts was tested on five selected wounds (5x5 cm each) of a patient with full-thickness burn. In another burn patient, type B CLSG consisting of autologous keratinocytes and allogenic dermal fibroblasts was grafted onto three wounds (5x5 cm each). RESULTS: The seeding efficacy of human keratinocytes on plain Laserskin increased from 75% to 95% when proliferative allogenic fibroblasts were grown as a feeder layer on the Laserskin. The seeding efficacy of rat keratinocytes increased from 36% to 88% in the presence of a proliferative allogenic fibroblast feeder layer, whereas human/rat keratinocytes had respective seeding efficacy of 98%/91% on Laserskin preseeded with mitomycin C-treated 3T3 cells. Skin biopsies of grafted type A CLSG on day 14 after grafting showed complete epithelialization without severe inflammation in 16 of 20 (80%) grafted surgical wounds in rats. There were eight (40%) and seven (35%) "takes" of the CLSG in types B and C, respectively. The infection rate in type B CLSG was two (10%). There was one (5%) infection in types A and C. The respective take rates on the two patients grafted with type B CLSG were 60% and 100%. CONCLUSION: The animal experiment and the preliminary clinical data showed that the CSLGs consisting of autologous keratinocytes and of autologous/allogenic fibroblasts are good human skin substitutes in terms of durability, biocompatibility, high seeding efficacy for keratinocytes, high graft take rate, and low infection rate. 相似文献
82.
BACKGROUND: Hip fracture is a major public health problem in Asia and the UK. The objectives of this study were to describe the trends of hip fracture in Hong Kong over the last decade, and to compare the incidence in Hong Kong with that from the Wessex Health Region of the UK in 1995. METHODS: The number of hip fractures was calculated using hospital discharge records for all public hospitals in Hong Kong in 1991 and 1995. Age-specific incidence rates were then calculated using the mid-year census population for the two years. These rates were presented with previously reported age-specific rates for Hong Kong in 1966 and 1985. These age-specific rates for Hong Kong in 1995 were compared with rates for the Wessex Health Region of the UK. The total number of hip fracture expected in 2010 was calculated by applying the age-specific rates of 1995 to the projected population for 2010. RESULTS: In 1995, a total of 1138 men and 2782 women in Hong Kong fractured their hip. The age-specific rates had remained static from 1985 to 1995, after substantial rise from 1966 to 1985. In 1995, the rates of hip fracture rates were 11/1000 in women and 5/1000 in men who were 70 years and older. These rates were almost identical to those observed in the Wessex Health Region of the UK. CONCLUSION: The age-specific incidence rates of hip fracture had not risen in Hong Kong in the last decade. The incidence of hip fracture in Hong Kong was similar to that in the UK in 1995. The total number of patients with hip fracture in Hong Kong will increase substantially in the future, as a result of the ageing of the population. 相似文献
83.
目的:研究蛋脑啡肽对猴免疫缺陷病毒(SIV)感染CEM×174 细胞kappa 阿片受体表达的调节作用。方法:用SIV 感染CEM×174 细胞并加入不同浓度蛋脑啡肽。在24 h 提取RNA,用RT-PCR 方法扩增kappa 阿片受体m RNA 并且进行定量分析。结果:显示SIV 能够抑制CEM×174 细胞的生长。在10- 7m ol/L蛋脑啡肽存在下,SIV 对细胞的损害减轻。10- 7m ol/L和10- 6m ol/L蛋脑啡肽不能改变正常细胞kappa 阿片受体的表达,但是在SIV 感染组的表达显著增高。结论:实验结果提示蛋脑啡肽能够维持正常淋巴细胞的生长。Kappa 阿片受体表达的改变可能与蛋脑啡肽对免疫细胞的调节机理有关 相似文献
84.
85.
PURPOSE: To investigate a case of isolated pedunculated congenital corneal dermoid. METHODS: Case report. RESULTS: In a 14-day-old infant, the pedunculated portion of the dermoid was removed and confirmed by histopathologic examination. No surgical complication or recurrence was encountered, and the patient is waiting for a rotational autokeratoplasty. CONCLUSIONS: Prompt treatment of such an unusual tumor is important to allow for visual rehabilitation and development. 相似文献
86.
Lam SR Devenyi RG Berger AR Dunn W 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》1999,34(7):389-393
BACKGROUND: In our institution the occurrence of endophthalmitis related to intraocular foreign bodies has been rare. In this review we analyse the outcome of eyes with retained intraocular foreign bodies presenting to two vitreoretinal surgeons over nearly 7 years. METHODS: Review of the records of 26 patients who presented to two surgeons in a tertiary care vitreoretinal service in Toronto between January 1989 and November 1995. Information documented included mechanism of injury, time from injury to definitive surgery, entry site, presence of vitreous hemorrhage, type of surgery performed, initial and final visual acuity, and development of endophthalmitis. RESULTS: All the injuries occurred in male patients, with a mean age of 36.1 (range 15 to 55) years. Most of the injuries occurred in the workplace, and in most cases (17 [65.4%]) the mechanism of injury was "metal on metal." The entry site was via a perforating wound of the cornea in 16 cases (61.5%). Almost all cases were repaired within 48 hours by means of pars plana vitrectomy. Concurrent lensectomy was required in 18 cases (69.2%) for lens damage at the time of the original injury. Vitreous hemorrhage was present in 22 cases (84.6%). One patient (3.8%) manifested clinically apparent endophthalmitis, which responded to intravitreal antibiotic therapy. Nineteen eyes (73.1%) had a final visual acuity of 6/24 or better. Eyes with coexisting or subsequent retinal detachment had significantly worse vision than those without retinal detachment (p < 0.001). INTERPRETATION: The incidence of endophthalmitis in our series is lower than that in other published series. Prompt definitive treatment was associated with a good prognosis in most cases. 相似文献
87.
Lam T. H.; Jiang C. Q.; Liu W. W.; Zhang W. S.; He J. M.; Zhu C. Q. 《Occupational medicine (Oxford, England)》1996,46(5):351-355
This cross-sectional study aimed to describe the pattern ofsmoking in relation to occupational hazard exposure in a workingpopulation in Guangzhou, China. In 1994, data on smoking andoccupational hazard exposure from occupational health recordsof 8,304 subjects aged 35 years or older from 47 randomly selectedfactories were studied. About 49% of the men and 55% of thewomen were exposed to dust, chemicals or other hazards. Theprevalence of smoking was 56.1% in men and in women. The prevalenceof smoking in men was higher in those who were younger, withprimary education or who were workers. In women, those who wereolder, with primary education or in management jobs had highersmoking prevalence. In men and women, subjects who were exposedto occupational hazards had higher smoking prevalence: the highest(71.6%) was found in male workers exposed to dust. Urgent tobaccocontrol measures are needed to prevent the epidemic of smoking-relatedand occupation-related diseases in the workplace in China. 相似文献
88.
E. Y. Liang W. W. M. Lam J. K. S. Woo C. A. van Hasselt C. Metreweli 《European radiology》1996,6(4):553-556
In order to study the features of sinonasal polyposis (SNP) on CT, 100 consecutive coronasal sinus CT examinations done for chronic inflamamtory sinonasal disease were reviewed. The CT findings of the 27 fully documented SNPs were analyzed. All our SNPs were bilateral. There was a strong tendency for extensive involvement. Nasal polyps were seen in 22 of 27 (81%); bony trabecular deossification in 23 of 27 (85%); widening of infundibulum in 26 of 27(96%). We discovered a new sign truncation of the bony middle turbinate, where the bulbous part of bony middle turbinate was missing, in 51 of 26 (58 %) of SNP patients without a previous history of middle turbinectomy, 12 of 15(80%) were bilateral. The one SNP patient (1 of 27) with previous middle turbinectomy was not regarded to be real truncation. Truncation of the bony middle turbinate is a characteristic and easily recognizable ancillary sign, and is not seen in other patterns of sinusitis. Together with other features on coronal sinus CT, this adds diagnostic confidence in diagnosing sinonasal polyposis.
Correspondence to: E. Y. Liang 相似文献
89.
To assess the impact of surgical stimulation on regulation of ventilation in anaesthetized man, we measured ventilation and the ventilatory responses to either hyperoxic hypercapnia or to isocapnic hypoxaemia in fifteen subjects anaesthetized with enflurane 1.1 MAC, just prior to and then during a surgical procedure. Anaesthesia alone reduced ventilation, increased Paco2 decreased the response to carbon dioxide and virtually abolished the response to hypoxaemia. The addition of operation at the same level of anaesthesia augmented ventilation and reduced Paco2 but did not improve the anaesthesia-induced impairment of the responses to hypercarbia and hypoxaemia. Over the range of PCO2 and PO2, values studied, the effects of surgery were constant and independent of chemical drive. A.M. Lam, M.D., Resident; J.L. Clement, R.N.; R.L. Knill, M.D., F.R.C.P.(C), Associate Professor; Department of Anaesthesia, University Hospital, University of Western Ontario, London, Canada. This work was supported by the Medical Research Council of Canada, Development Grant 150. Address reprint requests to Dr. R.L. Knill, Department of Anaesthesia, University Hospital, 339 Windermere Road, London, Ontario, Canada, N6A 5A5. 相似文献
90.