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1.
BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit the determination of femtogram amounts of 26Al in blood and in various tissues with good precision and free of external contamination. METHODS: In the present study we used trace quantities of 26Al to investigate the intestinal absorption and compartmentalization of aluminium in rats with renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single oral doses of 20 ng 26Al were administered to six animals in each group and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone, liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al were significantly lower in uraemic rats compared to controls, whereas urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/- 6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in uraemia. The target tissues of cellular transferrin-mediated 26Al uptake, liver and spleen, tended to show a larger degree of aluminium accumulation in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27 pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site of extracellular aluminium deposition, 26Al concentrations were more elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g). Estimated total 26Al accumulation in all measured target tissues was significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/- 7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/- 6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our data suggest that fractional absorption from a dietary level dose of 26Al is about 0.13%. Compartmentalization occurs in transferrin-dependent target tissues such as liver and spleen; however, in quantitative terms extracellular deposition in bone is more important. Uraemia has a significant effect on the intestinal absorption and compartmentalization of aluminium. It enhances fractional absorption and increases subsequent extracellular deposition of aluminium in bone. However, at the same time uraemia does not increase transferrin-dependent cellular accumulation of aluminium in liver and spleen.   相似文献   
2.
A rare side effect of minocycline is acute eosinophilic pneumonia. In the literature only ten cases have been reported. We report two cases of minocycline which induced (eosinophilic) alveolitis. A high fever, dry cough, dyspnoea and fatigue are the main features of the clinical picture. Peripheral blood eosinophilia and elevated total IgE content were seen in one patient. Bronchoalveolar lavage in this patient revealed eosinophilia. Transbronchial lung biopsies showed infiltration with eosinophilic granulocytes in both patients. Airway macrophages contained brown-black pigment granules. In the acute stage an important decrease in diffusion capacity was observed. The pulmonary and systemic symptoms promptly cleared up after discontinuation of minocycline. Provocation with minocycline was positive, because both patients noticed the same symptoms within one day.  相似文献   
3.
The objective of this study is to investigate the effects of an acute necrotizing pancreatitis (ANP), without biliary obstruction, on the migrating motor complex (MMC), small bowel bacterial overgrowth (SBBO), bacterial translocation (BT) and infection of the pancreas simultaneously. Rats were divided into four groups: mild pancreatitis, control, ANP and sham operated control. Jejunal myoelectrodes were used to measure MMCs. Blood, peritoneal fluid, bile, and abdominal organs were harvested for microbial culturing 72 h after induction of pancreatitis. The splenic portion of the pancreas was taken for histology. During ANP the MMC cycle length was significantly increased from 14.1 +/- 0.2 to 22.4 +/- 1.9 min (P < 0.05). The duodenum of ANP rats was in contrast with the other groups characterized by Enterobacteriacae (> 3 log 10 CFU g-1 in seven of 12 rats, P < 0.05). A positive correlation (r = 0.78, P < 0.01) existed between duodenal Gram-negative and anaerobic flora and the MMC cycle. Correlation between MMC cycle length and BT to the pancreas was positive as well (r = 0.70, P < 0.01). A positive correlation (r = 0.85, P < 0.01) was found between the severity of pancreatitis and duodenal bacterial overgrowth. During ANP without biliary obstruction, the jejunal MMC is disturbed and consequently SBBO occurs. The correlation between the severity of pancreatitis, the disturbance of the MMC and SBBO suggests an important pathophysiological role of the proximal small bowel in the infection of pancreatic necrosis.  相似文献   
4.
BACKGROUND: Ileo-neorectal anastomosis (INRA), an alternative restorative procedure, was developed to reduce the pouch-related complication rate with an (at least) equal functional result. METHODS: For this surgical outcome, data of all INRA patients, including bowel function and complications, were prospectively recorded. The reservoir capacity was determined repeatedly by physiologic tests. The anal sphincter complex was assessed by manometry and ultrasound examination. Evaluation of the neorectal mucosa was performed by endoscopy. RESULTS: An INRA procedure was carried out in 39/53 selected patients (47 ulcerative colitis and 6 familial adenomatous polyposis). Fourteen UC cases were converted to ileal pouch anal anastomosis or proctectomy only, because of impossibility to completely remove the rectal mucosa or short of length of the rectal stump. The median operation time for INRA was 323 min (range 240-518), with 1,400 ml blood loss (400-4,500). The reservoirs were permanently defunctioned in 2 patients--one because of reclassification into Crohn's disease, and one with pouchitis refractory to medical treatment. In 18 out of 37 cases, web-like stenoses occurred at the mucosa-anal level, which were treated by single (9) or repeated (5) dilatation or surgical stenoplasty (2). No pouch-related complications like pelvic sepsis, fistula or sexual dysfunction occurred. Thirteen patients had episodes of 'pouchitis', successfully treated with antibiotics, and 7 other cases, with functioning reservoirs, also had proximal 'non-specific' (i.e. no histological criteria of Crohn's disease found) small bowel inflammation. The median bowel frequency decreased from 15x/24 h initially to 7x/24 h at 2 years. Continence was perfect in 24/37 cases. Twelve out of 37 cases had occasional nocturnal soiling and passive nocturnal fecal incontinence was reported by 2/37 patients. The neorectal compliance volume recovered from 12.5 ml kPa after subtotal colectomy and 11 ml/kPa at 6 months after INRA to a neorectal compliance of 24 ml/kPa at 2 years' follow-up (p < 0.002; Wilcoxon signed rank test). CONCLUSION: The INRA procedure shows a low complication rate and reasonable functional results, there was however a considerable conversion rate in these first 53 cases and a high incidence of reclassification to CD.  相似文献   
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Background

Predicting total procedure time (TPT) entails several elements subject to variability, including the two main components: surgeon-controlled time (SCT) and anesthesia-controlled time (ACT). This study explores the effect of ACT on TPT as a proportion of TPT as opposed to a fixed number of minutes. The goal is to enhance the prediction of TPT and improve operating room scheduling.

Methods

Data from six university medical centres (UMCs) over seven consecutive years (2005-2011) were included, comprising 330,258 inpatient elective surgical cases. Based on the actual ACT and SCT, the revised prediction of TPT was determined as SCT × 1.33. Differences between actual and predicted total procedure times were calculated for the two methods of prediction.

Results

The predictability of TPT improved when the scheduling of procedures was based on predicting ACT as a proportion of SCT.

Conclusions

Efficient operating room (OR) management demands the accurate prediction of the times needed for all components of care, including SCT and ACT, for each surgical procedure. Supported by an extensive dataset from six UMCs, we advise grossing up the SCT by 33% to account for ACT (revised prediction of TPT = SCT × 1.33), rather than employing a methodology for predicting ACT based on a fixed number of minutes. This recommendation will improve OR scheduling, which could result in reducing overutilized OR time and the number of case cancellations and could lead to more efficient use of limited OR resources.  相似文献   
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Objective

We performed a systematic review to assess the outcome of endoscopic transluminal necrosectomy in necrotising pancreatitis with additional focus on indication, disease severity, and methodological quality of studies.

Design

We searched the literature published between January 2005 and June 2013. Cohorts, including patients with (infected) necrotising pancreatitis, undergoing endoscopic necrosectomy were included. Indication, disease severity, and methodological quality were described. The main outcomes were mortality, major complications, number of endoscopic sessions, and definitive successful treatment with endoscopic necrosectomy alone.

Results

After screening 581 papers, 14 studies, including 455 patients, fulfilled the eligibility criteria. All included studies were retrospective analyses except for one randomized, controlled trial. Overall methodological quality was moderate to low (mean 5, range 2–9). Less than 50 % of studies reported on pre-procedural severity of disease: mean APACHE-II score before intervention was 8; organ failure was present in 23 % of patients; and infected necrosis in 57 % of patients. On average, four (range 1–23) endoscopic interventions were performed per patient. With endoscopic necrosectomy alone, definitive successful treatment was achieved in 81 % of patients. Mortality was 6 % (28/460 patients) and complications occurred in 36 % of patients. Bleeding was the most common complication.

Conclusions

Endoscopic transluminal necrosectomy is an effective treatment for the majority of patients with necrotising pancreatitis with acceptable mortality and complication rates. It should be noted that methodological quality of the available studies is limited and that the combined patient population of endoscopically treated patients is only moderately ill.  相似文献   
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