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1. The effects of graded treadmill exercise on renal blood flow (RBF) were examined in seven rabbits, in which congestive heart failure (CHF) was produced by the administration of doxorubicin, 1 mg/kg, twice weekly for 8 weeks, and in seven controls. A third group of five rabbits underwent doxorubicin treatment with the addition of surgical section of the left renal sympathetic nerve. 2. During submaximal exercise, there was a small reduction in RBF in controls, which was greatly exaggerated in CHF. 3. In both control and heart failure rabbits, there was a precipitous fall in RBF as exercise fatigue developed. 4. Renal sympathectomy ablated these changes in RBF during exercise. 5. It is concluded that in heart failure there is an exaggerated, sympathetically mediated, diversion of blood flow away from the kidney. The onset of exercise fatigue in both normal and heart failure rabbits is accompanied by a marked intensification of this process.  相似文献   
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Few studies used paired kidneys for comparison between tacrolimus and cyclosporine in renal transplantation. Most of the published data used whole blood trough levels for drug monitoring. However, the use of limited sampling strategy and abbreviated formula to estimate the 12-h area under concentration-time curve (AUC(0-12)) allowed better prediction of drug exposure. Sixty-six first cadaveric renal transplant recipients receiving paired kidneys were randomized to receive either tacrolimus-based (n = 33) or cyclosporine microemulsion (Neoral)-based therapies (n = 33). Abbreviated AUC(0-12) was used for drug monitoring and dose titration. Mean follow-up duration was 2.8 +/- 2 years. The patient and graft survival were comparable. Fewer incidence of acute rejection was observed in tacrolimus group (15% vs. 27.3%) though the difference was not significant (P = 0.23). The absolute value and the rate of decline of creatinine clearance were both significantly better in tacrolimus-treated patients. Prevalence of hypertension, post-transplant diabetes mellitus, infection, and malignancy were similar in both groups. Prevalence of hypercholesterolemia (11/33 vs. 4/33) and gum hypertrophy (6/33 vs. 1/33) was more common in cyclosporine-treated patients (P = 0.04 in both parameters). This was the first prospective, randomized study with paired kidney analysis showing the renal function was significantly better in tacrolimus-treated patients than in cyclosporine-treated patients.  相似文献   
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The authors treated 17 patients with achalasia by a thoracoscopic (15 patients) or laparoscopic (2 patients) Heller myotomy. All patients had dysphagia and an upper gastrointestinal series demonstrating a dilated esophagus with a bird-beak deformity at the cardia. Manometry showed a mean lower esophageal sphincter (LES) pressure of 32 +/- 4 mmHg, incomplete sphincter relaxation on swallowing, and no primary esophageal peristalsis. After operation, mean LES pressure was 10 +/- 2 mmHg. Fifteen patients were fed on the second postoperative day. The average hospital stay was 3 days, and there were no deaths or major complications. In three early patients, the myotomy was not carried far enough onto the stomach, and dysphagia persisted until a second myotomy was performed (laparoscopically in two patients). The authors found that having an endoscope in the esophagus during the operation facilitated exposure and was vital to determine the appropriate length of the myotomy. With regard to dysphagia, final results were excellent in 12 patients (70%), good in two patients (12%), fair in two patients (12%), and poor in one patient (6%). Heller myotomy can be safely and reliably performed with minimally invasive techniques. Dysphagia is relieved, postoperative pain is minimal, hospital stay is short, and the patient can return quickly to normal activity.  相似文献   
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The efficacy and limitations of percutaneous endoscopic gastrostomy.   总被引:2,自引:0,他引:2  
We analyzed 64 percutaneous endoscopic gastrostomy procedures performed by us between 1986 and 1990. Thirty patients had neurologic disease; 16 had head and neck cancers; eight had other malignancies; two had acquired immunodeficiency syndrome; and eight had other problems. Seven patients died within 30 days of complications (n = 4) or the primary illness (n = 3). Mean follow-up was 6 months; an additional patient died of aspiration and eight others died of their underlying illness. There were 19 complications (32%). Four wound complications occurred. Nine patients developed aspiration pneumonia within 3 days of the procedure, four of whom died in the hospital. Of the 24 patients with a history of aspiration, nine experienced aspiration during or after percutaneous endoscopic gastrostomy. Patients with a history of aspiration were more likely to have perioperative aspiration pneumonia, and patients who experienced aspiration were more likely to die.  相似文献   
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Objective Gallstone bacteria provide a reservoir for biliary infections. Slime production facilitates adherence, whereas β-glucuronidase and phospholipase generate colonization surface. These factors facilitate gallstone formation, but their influence on infection severity is unknown. Methods Two hundred ninety-two patients were studied. Gallstones, bile, and blood (as applicable) were cultured. Bacteria were tested for β-glucuronidase/phospholipase production and quantitative slime production. Infection severity was correlated with bacterial factors. Results Bacteria were present in 43% of cases, 13% with bacteremia. Severe infections correlated directly with β-glucuronidase/phospholipase (55% with vs 13% without, P < 0.0001), but inversely with slime production (55 vs 8%, slime <75 or >75, P = 0.008). Low slime production and β-glucuronidase/phospholipase production were additive: Severe infections were present in 76% with both, but 10% with either or none (P < 0.0001). β-Glucuronidase/phospholipase production facilitated bactibilia (86% with vs 62% without, P = 0.03). Slime production was 19 (±8) vs 50 (±10) for bacteria that did or did not cause bacteremia (P = 0.004). No bacteria with slime >75 demonstrated bacteremia. Conclusions Bacteria-laden gallstones are biofilms whose characteristics influence illness severity. Factors creating colonization surface (β-glucuronidase/phospholipase) facilitated bacteremia and severe infections; but abundant slime production, while facilitating colonization, inhibited detachment and cholangiovenous reflux. This shows how properties of the gallstone biofilm determine the severity of the associated illness. Presented at the annual meeting of the Society for Surgery of the Alimentary Tract, held May 20–24, 2006 in Los Angeles, California.  相似文献   
9.
Spillage of gallstones may occur in the course of laparoscopic cholecystectomy. The incidence of this mishap and its consequences are variable. Ignored by many surgeons, stone spillage may be the source of significant morbidity many years after surgery. In this report, we describe the clinical course of a patient who presented with upper abdominal pain and swelling. The past history was positive for laparoscopic cholecystectomy 15 years earlier. After excision, the swelling was found to be a pseudocyst formed around spilled gallstones during a previous cholecystectomy. Apart from postoperative wound infection, the patient recovered well and remains so. Here, we discuss the problem and provide suggestions for spillage prevention and stone retrieval once spillage occurs.  相似文献   
10.
From two different specimens of a chronic prosthetic hip infection taken at an interval of 2 months a slow-growing gram-negative bacterium was isolated in pure culture. The strain grew with the typical features of a small-colony variant (SCV). 16S rRNA sequencing identified the bacterium as Escherichia coli. Biochemical characterization demonstrated multiple phenotypic alterations of a mutant carrying a defect in the heme biosynthetic pathway (Hem): (i) catalase and nitrate reductase reactions were both negative, (ii) a negative benzidine reaction demonstrated the lack of heme-containing cytochromes, and (iii) growth stimulation under anaerobic conditions as well as gentamicin resistance indicated defective aerobic respiration. PCR and Southern hybridization demonstrated that the mutation of the SCV of E. coli was localized in the hemB gene and was most likely due to a deletion of the hemB gene. On blood agar plates revertants were recognized growing as normal-sized colonies between the dominant small colonies of the strain. Feeding experiments indicated that the revertants but not the small colonies were permeable for hemin. A strong antibody response against the infecting SCV of E. coli was found. To our knowledge, this is the first report of a Hem E. coli strain as the etiological agent of a chronic bacterial infection.  相似文献   
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