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BACKGROUND: Most comparisons of hemodialysis (HD) and peritoneal dialysis (PD) have used mortality as an outcome. Relatively few studies have directly compared the hospitalization rates, an outcome of perhaps equal importance, of patients using these different dialysis modalities. METHODS: Eight hundred twenty-two consecutive patients at 11 Canadian institutions with irreversible renal failure had an extensive assessment of comorbid illness and initial mode of dialysis collected prospectively immediately prior to starting dialysis therapy. The cohort was assembled between March 1993 and November 1994. The mean follow-up was 24 months. Admission data were used to compare hospitalization rates in HD and PD. RESULTS: Thirty-four percent of patients at baseline and 50% at three months used PD. Twenty-five percent of HD and 32% of PD patients switched dialysis modality at least once after their first treatment (P = NS). Nine percent of HD patients and 30% of PD patients switched modality after three months (P < 0. 001). Total comorbidity was higher in HD patients at baseline (P < 0. 001) and at three months (P = 0.001). The overall hospitalization rate was 40.2 days per 1000 patient days after baseline and 38.0 days per 1000 patient days after three months. When an adjustment was made for baseline comorbid conditions, patients on PD had a lower rate of hospitalization in intention-to-treat analysis according to the type of dialysis in use at baseline (RR 0.85, 95% CI, 0.82 to 0.87, P < 0.001), but a higher rate according to the type of dialysis in use three months after study entry (RR 1.31, 95% CI, 1.27 to 1.34, P < 0.001). In analyses based on the amount of time actually spent on each treatment modality, PD was associated with a higher rate of hospitalization when analyzed according to the type of dialysis in use at baseline (RR 1.10, 95% CI, 1.07 to 1.13, P < 0.001) and according to the type of dialysis in use three months after study entry (RR 1.26, 95% CI, 1.23 to 1.30, P < 0.001). CONCLUSIONS: Conclusions regarding comparative hospitalization rates are heavily dependent on the analytic starting point and on whether intention-to-treat or treatment-received analyses are used. When early treatment switches are accounted for, HD is associated with a lower rate of hospitalization than PD, but the effect is modest.  相似文献   
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This study reports the synthesis of steroidal quaternary ammonium compounds 11 and 12, with quaternary nitrogen at position 3 and 16 of the steroid nucleus in 5α-epiandrosterone series; along with their neuromuscular blocking activity using chick biventer cervicis muscle preparation. The compound 12 was found to be five times more potent than 11 in reducing twitch response to nerve stimulations, indicating the importance of extended interonium distances and 17-acetoxy function for potent antagonist activity.  相似文献   
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We designed a joint research project to investigate the incidence of ischemic heart diseases in patients undergoing noncardiac surgery and to define the risk of perioperative cardiac complications in these patients. Of the 8358 surgical patients in the 8 departments of anesthesiology between March 1997 and June 1997, 328 (3.9%) had ischemic heart diseases. Among the 328 patients, 54 (16.4%) developed perioperative cardiac events, including myocardial infarction (3 patients) and either lethal or potentially dangerous dysrhythmias (51 patients). Preoperative cardiac assessments were performed while the anesthetic techniques including intensive monitoring and perioperative prophylactic therapy were also employed. Patients with ischemic heart diseases received various types of preoperative evaluation to identify the degree of coronary artery disease and to assess the overall cardiac function. The patients were monitored using a multilead electrocardiogram, an arterial line, a central venous catheter, a pulmonary artery catheter, and by transesophageal echocardiography intraoperatively. Therapeutically, isosorbide, nitroglycerin, beta-blockers, calcium channel blockers, and/or nicorandil were administered to prevent perioperative ischemia. So far, no generally accepted management strategies have been established in patients with cardiovascular disorders based on large-scale outcome trials in Japan. Therefore, nationwide large multicenter trials are awaited with interest in order to establish helpful guidelines to improve the perioperative management and to reduce ischemia in cardiac patients undergoing noncardiac surgery.  相似文献   
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Phototherapy has become a treatment of choice in many areas of medicine. Light can deliver energy to tissue selectively, targeting specific structures in order to induce the desired therapeutic outcome. For the safe and effective removal of unwanted hair, the key optical parameters are wavelength, pulse duration and energy density, and can vary dependent upon skin and hair color. In recent years, the use of broad spectrum white light sources has proved to be safe and efficacious in the removal of hair with minimal short‐ or long‐term side effects. Whilst these highly flexible devices can achieve the desired results, there is scope for improvement. There are two key limitations to these devices: an inability to produce a ‘true’ long pulse matched to the thermal relaxation time of the hair structure and fluctuations in the output spectrum can lead to ineffective treatment with an increased risk of side effects. This paper describes an alternative approach to producing long pulse, constant spectrum optical pulses and presents clinical data showing improved efficacy in long‐term hair removal.  相似文献   
26.
An epiphrenic oesophageal diverticulum is most commonly a pulsion diverticulum which develops consequent to protrusion of mucosa through the muscular wall of the distal oesophagus. Most of them are associated with underlying oesophageal motility disorders. The predominant symptoms are dysphagia with regurgitation, and sometimes retrosternal pain, if accompanied by spasm of the oesophagus. Surgical management is recommended for symptomatic patients. Traditional procedures include thoracotomy or laparotomy with excision of the diverticula, but these are associated with high morbidity. Laparoscopic approach is a safe treatment option associated with lesser morbidity. Here, we present a case of epiphrenic diverticulum which was treated by the robotic approach without any complication. There was also no associated motility abnormality in our case so fundoplication was not done. Robotic surgery is a useful tool while operating near the hiatus and gastro-oesophageal junction. We consider transhiatal robotic approach as a safe and easy approach for surgery of epiphrenic diverticulum.  相似文献   
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Glioblastomas and brain metastases demonstrate avid uptake of 2‐[18F]fluoro‐2‐deoxyglucose by positron emission tomography and display perturbations of intracellular metabolite pools by 1H MRS. These observations suggest that metabolic reprogramming contributes to brain tumor growth in vivo. The Warburg effect, excess metabolism of glucose to lactate in the presence of oxygen, is a hallmark of cancer cells in culture. 2‐[18F]Fluoro‐2‐deoxyglucose‐positive tumors are assumed to metabolize glucose in a similar manner, with high rates of lactate formation relative to mitochondrial glucose oxidation, but few studies have specifically examined the metabolic fates of glucose in vivo. In particular, the capacity of human brain cancers to oxidize glucose in the tricarboxylic acid cycle is unknown. Here, we studied the metabolism of human brain tumors in situ. [U‐13 C]Glucose (uniformly labeled glucose, i.e. d ‐glucose labeled with 13 C in all six carbons) was infused during surgical resection, and tumor samples were subsequently subjected to 13C NMR spectroscopy. The analysis of tumor metabolites revealed lactate production, as expected. We also determined that pyruvate dehydrogenase, turnover of the tricarboxylic acid cycle, anaplerosis and de novo glutamine and glycine synthesis contributed significantly to the ultimate disposition of glucose carbon. Surprisingly, less than 50% of the acetyl‐coenzyme A pool was derived from blood‐borne glucose, suggesting that additional substrates contribute to tumor bioenergetics. This study illustrates a convenient approach that capitalizes on the high information content of 13C NMR spectroscopy and enables the analysis of intermediary metabolism in diverse cancers growing in their native microenvironment. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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