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91.
High retropharyngeal neuroblastic tumors in children have been excised and debulked transorally or cervically, often with a covering tracheostomy. Although we and others have approached high thoracic lesions thoracoscopically, the trapdoor incision (or modification thereof) is generally reserved for cervicothoracic tumors with significant vessel encasement around the thoracic inlet. We report a case of symptomatic ganglioneuroma extending from the nasopharynx, at the level of the skull base, down to the aortic arch: macroscopic clearance was achieved via an extended trapdoor incision and without recourse to tracheostomy, transoral surgery, or transfusion.  相似文献   
92.
原发性脾囊肿是一种罕见的疾病,目前尚缺乏对该疾病的理想治疗方法的相关研究.大多数原发性脾囊肿是上皮性囊肿.近几年,腹腔镜脾脏外科手术普及率不断提高.该研究报告了关于经腹腔镜保脾手术治疗脾囊肿的相关经验.1996年至2006年间,作者治疗了11例有症状的非寄生虫性脾脏巨大囊肿病人.病人均诉左上腹涨满症状,触诊可扪及腹部包块.术前腹部超声及CT均已明确诊断.病人接受经腹腔镜脾脏囊肿部分切除术或脾脏囊肿开窗减压术.结果发现,7例病人为脾脏间皮囊肿,2例为脾脏表皮样囊肿,2例为脾脏假性囊肿,没有发现囊肿癌变.手术操作时间为62~85 min,无中转开腹.  相似文献   
93.

Purpose

Operative strategy and antibiotic policy in treating infantile hypertrophic pyloric stenosis (IHPS) may vary widely. This study surveys current practice in the United Kingdom and Ireland among members of the British Association of Paediatric Surgeons.

Methods

The study used postal and email survey of consultant pediatric surgeons.

Results

One hundred five questionnaires were distributed, and 94 replies (90% response) were received. Umbilical pyloromyotomy is performed exclusively by 57 surgeons. Fourteen surgeons (15%) use laparoscopy, whereas 5 (randomized trial in progress) use the umbilical or laparoscopic route. Eight reported that the umbilical or classical right upper quadrant (RUQ) incision is undertaken at their institution according to surgeon's preference. Ten surgeons only deploy an RUQ incision. Antibiotic practice showed that 40 (70%) using the umbilical incision prescribe prophylactic therapy, whereas only 6 adopting other operative techniques (RUQ incision or laparoscopy) found this policy beneficial. More than 50% surveyed do not routinely recommend antibiotics.

Conclusion

Umbilical pyloromyotomy is used by most pediatric surgeons in the United Kingdom and Ireland. Laparoscopy is increasingly popular in minimally invasive centers. The RUQ incision is used by a minority of surgeons. Antibiotic prophylaxis was common with the umbilical incision only. The superior cosmetic results offered by umbilical pyloromyotomy and laparoscopy are a benchmark for surgeons currently providing contemporary care for babies with IHPS.  相似文献   
94.
Background: Recent studies have shown a substantial decline in caries experience in Australian Army recruits between 1996 and 2002–2003, and in Australian adults between 1987–1988 and 2004–2006. However, studies in children have reported an increasing trend in caries experience between 1998 and 2002. The aim of this study was to investigate caries experience in Australian Army recruits in 2008. Methods: A cross‐sectional study involving 1084 Australian Army recruits was conducted from January to May 2008. Data were obtained from a clinical dental examination with bitewing radiographs, and a questionnaire elicited socio‐demographic data and history on lifetime exposure to fluoridated drinking water. Results: Mean DMFT scores were 3.16, 4.08, 5.16 and 7.11 for recruits aged 17–20, 21–25, 26–30 and 31–35 years, respectively. Recruits with a lifetime exposure to fluoridated drinking water had a mean DMFT of 3.02, while recruits with no exposure had a mean DMFT of 3.87. Conclusions: Caries experience in Australian Army recruits aged 17–25 years increased between 2002–2003 and 2008. Recruits with lifetime exposure to fluoridated drinking water had 25 per cent less caries experience compared with recruits who had no exposure to fluoridated drinking water after adjusting for the effects of age, gender, education and socio‐economic status.  相似文献   
95.
Background Melanoma is a tumour with a very variable progression. Whilst some melanomas grow slowly over many years, others can reach several millimetres in thickness in just a few weeks. Since melanoma is a visible superficial tumour, the information obtained from the clinical interview may be of use to calculate the speed of growth of the melanoma. Objective This study aims to assess the growth rate (GR) of melanomas and the association of this GR with various clinical and pathological factors and their usefulness as prognostic markers for localized invasive cutaneous melanomas. Methods The GR of melanomas was calculated as the ratio of tumour thickness to time of development, as obtained from the clinical history (in millimetres per month). Results Applying the GR calculation to patients with a localized melanoma showed a significant association between melanomas with a GR greater than 0.4 mm per month and an age of 65 years or over, male sex, nodular melanoma, tumour thickness, level of invasion, the presence of ulceration and a high mitotic index. As an independent prognostic factor for overall survival, the GR proved to be significant (P = 0.024). Conclusion The GR of localized cutaneous melanomas may be a possible prognostic factor for survival. Additionally, rapid GR is associated with male patients more advanced in age at diagnosis, which suggests the need to assess new strategies for the early detection of these melanomas.  相似文献   
96.
Background:  Although community water fluoridation has been one of the cornerstone strategies for the prevention and control of dental caries, questions are still raised regarding its cost-effectiveness. This study assessed the impact of changing dental needs on the cost savings from community water fluoridation in Australia.
Methods:  Net costs were estimated as Costs(programme) minus Costs(averted caries). Averted costs were estimated as the product of caries increment in non-fluoridated community, effectiveness of fluoridation and the cost of a carious surface. Modelling considered four age-cohorts: 6–20, 21–45, 46–65 and 66+ years and three time points 1970s, 1980s, and 1990s. Cost of a carious surface was estimated by conventional and complex methods. Real discount rates (4, 7 (base) and 10%) were utilized.
Results:  With base-case assumptions, the average annual cost savings/person, using Australian dollars at the 2005 level, ranged from $56.41 (1970s) to $17.75 (1990s) (conventional method) and from $249.45 (1970s) to $69.86 (1990s) (complex method). Under worst-case assumptions fluoridation remained cost-effective with cost savings ranging from $24.15 (1970s) to $3.87 (1990s) (conventional method) and $107.85 (1970s) and $24.53 (1990s) (complex method). For 66+ years cohort (1990s) fluoridation did not show a cost saving, but costs/person were marginal.
Conclusions:  Community water fluoridation remains a cost-effective preventive measure in Australia.  相似文献   
97.
The case of a 15-year-old patient presenting with pain as well as paraesthesia over the lateral aspect of the leg is reported. Clinical and radiological investigations showed an aneurysmal bone cyst arising from the proximal fibula and pressing on the common peroneal nerve. Surgical decompression of the nerve and curettage of the cyst was performed resulting in complete resolution of his symptoms. Our aim is to alert surgeons that this problem may occur and that the entire nerve needs to be exposed when dealing with the cyst.  相似文献   
98.
It has been reported that chloroform administered to BDF1 mice by inhalation for 2 years at concentrations of 5, 30 or 90 p.p.m. for 6 h/day, 5 days/week induced an increase in renal cell tumors in male but not female mice exposed to the doses of 30 and 90 p.p.m. A small increase in liver tumors was statistically significant in the female mice at 90 p.p.m. if the incidences of carcinomas and adenomas were combined. Because chloroform is not a DNA reactive mutagen, a 13-week time-course and dose-response study was conducted under conditions of the original bioassay to examine whether regenerative cell proliferation was an underlying mechanism of carcinogenesis. Mice were given bromodeoxyuridine via infusion during the last 3.5 days prior to necropsy to label cells in S-phase. Chloroform induced pathology and regenerative cell proliferation, measured as the labeling index (LI, percentage of cells in S-phase), were assessed microscopically and immunohistochemically. Male mice exposed to 30 and 90 p.p.m. exhibited a dose-dependent increase in regenerating tubules within the renal cortex and up to a 31-fold increase in LI. No renal lesions or increased LI were observed in females. Increased centrilobular to midzonal hepatocyte degeneration and vacuolation and a 7-fold increase over controls in the hepatocyte LI were observed in the female mice at 90 p.p.m. at 13 weeks. Males exhibited similar pathology, but the increase in LI was not sustained. The observed correlations between cytolethality and regenerative cell proliferation with tumor formation supports extensive evidence that chloroform induces cancer via a non- genotoxic-cytotoxic mode of action. A concentration of 5 p.p.m. is the no-observed-adverse-effect level for nephrotoxicity, cell proliferation and cancer. An appropriate safety factor applied to this value is a straightforward approach to cancer risk assessment that is consistent with the mode of action of chloroform.   相似文献   
99.
100.
In 3646 children with at least one confirmed urinary tract infection the prevalence of vesicoureteric reflux at presentation was correlated with progressive renal damage during follow up of not less than two and up to 16 years. Reflux was not demonstrated either at presentation or at any subsequent time in almost one half of the children who suffered progressive renal damage and was not a risk factor for progressive renal damage in boys under 1 year. It was an important risk factor in boys over 1 year and in girls of any age. The risk of progressive renal damage in children in whom micturating cystourethrography (MCU) did not reveal vesicoureteric reflux was substantially greater than in those who indirect isotope voiding study (IVS) did not show reflux. The risk of deterioration for those in whom reflux was demonstrated was similar for both techniques. This discrepancy indicates an appreciably higher false negative rate for the MCU than the IVS. Dilatation of the renal pelvis detected by ultrasound was associated with a significantly increased risk of progressive damage only when associated with reflux, but most children with progressive damage did not have a dilated collecting system at presentation.  相似文献   
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