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81.
Background Gastric carcinoma is a significant cause of death in Ireland. Surgery offers the best option of cure, but the five-year survival following resection remains dismal at 10–15%. Experience from Japan and from some Western units suggest that an extended (D2) lymphadenectomy in association with gastrectomy increases the prospect of cure, but concern about the morbidity and mortality of this operation and lack of evidence from randomised studies has limited its acceptance. Aims This study reports the experience of a specialist upper gastrointestinal unit with D2 gastrectomy in a four-year audit. Methods Sixty-two resections were performed for gastric cancer. Results Nineteen patients were deemed unsuitable for the D2 procedure and underwent a more limited lymphadenectomy (DO or D1). Forty-three patients underwent D2 resection, 12 with an oesophagogastrectomy, 22 with total gastrectomy and nine with a sub-total distal resection. Eight patients undergoing D2 resection had extended resections, five with splenectomy and three with a distal pancreatectomy. Post-operative complications occurred in 31% of patients. Thirty-day and 90-day mortality were zero. Median survival was 822 days in the D2 group (range 120–1,320). Conclusions These results show that a D2 gastrectomy can be performed with a low morbidity and mortality and a median survival of greater than two years.  相似文献   
82.
Background The contribution of dysmotility to dysphagia in oesophageal cancer is unclear. Aim To examine oesophageal motility in patients with oesophageal carcinoma and to assess the effect of chemoradiotherapy on motility. Methods Stationary manometry and 24-hour pH-metry were performed in 12 patients with oesophageal carcinoma and one week following completion of chemoradiotherapy using 5-fluorouracil (5-FU), cisplatin and 40Gy radiotherapy. Results All patients had abnormal motility prior to treatment. Peristalsis was impaired in 11 patients with a mean (SD) of 25% (9) of waves normally propagated. Eight patients had 20% or more simultaneous waves. Following chemoradiotherapy, the percentage of waves normally propagated increased from 25% (9) to 52% (10) (p < 0.03) and normal peristalsis was restored in four patients. The percentage of simultaneous waves decreased from 38% (11) to 21.6% (10) (p=0.129) while the percentage of dropped or increased waves decreased from 20% (11) to 8.3% (4) (p=0.264). Conclusions Oesophageal motility is disturbed in oesophageal cancer. Dysphagia in oesophageal cancer may be partly explained by oesophageal dysmotility. This is improved by chemotherapy.  相似文献   
83.
OBJECTIVES: This article compares a linear risk-adjusted model of medical expenditures for Medicare patients with a model that explicitly account for skewness in distribution of expenditures. METHODS: A model of expenditures and a model of the square root of expenditures, each expressed as linear combinations of risk adjusters, are estimated using data from the 1992 through 1994 Medicare Current Beneficiary Surveys. Five sets of risk adjusters are considered. Each combination of model and set of risk adjusters is tested for linearity, heteroscedasticity, in-sample fit (R2), forecast performance (forecast bias and forecast mean squared error), and overfitting the data. We analyze forecast performance (1)based on forecasts in same year used for estimation, and (2)based on forecasts in the year following that used for estimation. RESULTS: In the first analysis, the model using a square root transformation of expenditures as the dependent variable and the more parsimonious specification of risk adjusters performs best in terms of forecast squared error and overfitting. The untransformed model performs best in terms of forecast bias in each group based on severity of disability, with the exception of the severely disabled for whom the square root model is best. In the second analysis, the square root model performs better than the untransformed model in terms of forecast squared error, but neither model is statistically distinguishable from zero in terms of bias. CONCLUSIONS: Accounting for skewness in expenditures tends to improve precision but not necessarily bias, except among the severely disabled. Adjusting for health status improves risk adjustment.  相似文献   
84.
Effects of chronic application of the fungicide Derosal(R) (active ingredient carbendazim) were studied in indoor macrophyte-dominated freshwater microcosms. The concentrations (0, 3.3, 33, 100, 330 and 1000 μg/l) were kept at a constant level for 4 weeks. This paper is the first of a series of two, and describes the fate of carbendazim and its effects on water quality parameters, breakdown of POM, and responses of macroinvertebrates. Carbendazim proved very persistent in the water layer. Values for t(12) varied between 6 and 25 weeks, and decreased with the treatment level. Significant effects on water quality parameters (DO, pH, alkalinity, conductivity) could not be demonstrated. After 4 weeks of incubation, the breakdown of Populus leaves was significantly slower at the two highest carbendazim concentrations. The macroinvertebrate community was seriously affected by carbendazim application, with Oligochaeta, Turbellaria, Hirudinea and some Crustacea as the most sensitive groups. The snail Bithynia decreased in numbers, but other gastropods increased in numbers. Safety factors as proposed by the Uniform Principles (European Union) for the risk assessment of pesticides, to be multiplied with toxicity data of the standard test species (Daphnia, fish, algae), appeared to ensure adequate protection of sensitive populations present in the microcosms.  相似文献   
85.
86.
Lidocaine has been used in treatment of patients with refractory headache. Personal observations of neuropsychiatric toxicity in these patients led us to review our cases and the literature systematically for lidocaine side-effects, especially neuropsychiatric symptoms. In our series of 20 patients, side-effects were observed in all, the most frequent being neuropsychiatric (75%) and cardiological (50%). When reviewing published series on intravenous lidocaine use, reports of side-effects range from 0 to 100%, with neuropsychiatric symptoms being reported in 1.8–100%. Thirty-six case reports of lidocaine-induced psychiatric symptoms were also analysed. Psychiatric symptoms of toxicity were similar in most patients, despite their differing ages, pathologies, co-therapies and lidocaine dosages. In conclusion, lidocaine neuropsychiatric toxicity has a well-recognized stereotypical clinical presentation that is probably unrecognized in headache series. As lidocaine represents an emerging alternative therapy in headache, particularly in short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing, clinicians and patients should be aware of the extent of this problem.  相似文献   
87.
It remains an open question as to whether cortical spreading depression (CSD) is the pathophysiological correlate of the neurological symptoms in migraine with aura. In the experimental animal, CSD is an electrophysiological phenomenon mainly mediated via NMDA receptors. However, according to case reports in humans, visual aura in migraine can be alleviated by vasodilator substances, such as amyl nitrite and isoprenaline. There is also circumstantial evidence that brainstem nuclei (dorsal raphe nucleus and locus coeruleus) may play a pivotal role in the initiation of aura. In this study, CSD was elicited in alpha-chloralose anesthetized cats by cortical needle stab injury and monitored by means of laser Doppler flowmetry. Topical application of isoprenaline (0.1-1%) and amyl nitrite (0.05%) onto the exposed cortex had no effect on the elicitation or propagation of CSD. Also, after supracollicular transection, subsequent CSDs showed no differences in the speed of propagation and associated flow changes. We conclude from these data that--given CSD probably exists in humans during migraine--spreading neurological deficits during migraine aura are independent of brainstem influence and have a primarily neuronal rather than vascular mechanism of generation.  相似文献   
88.

Background  

This study aims to contribute to the knowledge of the influence of comorbidity in OA. The objectives of the study were (i) to describe the prevalence of comorbidity and (ii) to describe the relationship between comorbidity (morbidity count, severity and the presence of specific diseases) and limitations in activities and pain in elderly patients with knee or hip OA using a comprehensive inventory of comorbidity.  相似文献   
89.
A 16-y-old boy who had undergone bone marrow transplantation for relapsed acute lymphoblastic leukaemia developed liver cirrhosis and refractory ascites, which did not respond to salt restriction, diuretics and abdominal paracentesis. Liver transplantation was not feasible because of poor nutritional status, pre-existing renal dysfunction and uncertainty about the prognosis of his leukaemia. The patient underwent a successful transjugular intrahepatic portosystemic shunt (TIPS), with immediate resolution of ascites, enabling cessation of diuretics and improvement in nutritional status. At 24 mo following TIPS there has been no re-accumulation of ascites. CONCLUSION: TIPS may have a role in the management of refractory ascites secondary to liver cirrhosis in selected children.  相似文献   
90.
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