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61.
OBJECTIVE: To assess our long term results of lateral pancreaticojejunostomy in patients with alcoholic pancreatitis. DESIGN: Retrospective study. SETTING: University hospital, France. SUBJECTS: 57 patients (48 men, 9 women, mean (SD) age 46 (7) years who required surgical treatment of chronic alcoholic pancreatitis between January 1977 and October 1995. INTERVENTIONS: Lateral pancreaticojejunostomy with or without another procedure. Outcome classified as excellent, good, fair, or poor. MAIN OUTCOME MEASURES: Postoperative morbidity and mortality; relief of pain; reduction in use of analgesics and exocrine supplements; effect on exocrine and endocrine insufficiency; and return to paid work. RESULTS: There were no postoperative deaths and no pancreatic fistulae, but there were 17 other postoperative complications (30%). Median follow up was 65 months (range 8-206), during which 12 patients died (21%). Result was judged excellent in 16 (28%), good in 27 (47%), fair in 5 (9%), and poor in 9 (16%). Pain control was significantly improved, analgesic usage decreased, less pancreatic enzyme supplementation was required, and 25 patients returned to paid work (p = 0.0001 in each case). Exocrine and endocrine function remained stable. The results were better if the patient gave up misusing alcohol (p = 0.03) and if the operation was done within 4 years of the development of pancreatitis (p = 0.03). CONCLUSIONS: Lateral pancreaticojejunostomy is a safe procedure that can improve functional outcome in patients with chronic alcoholic pancreatitis, and does not worsen pancreatic function.  相似文献   
62.
Systemic vascular resistance (SVR) classification is useful for the diagnosis and prognosis of critical pathophysiological conditions, with the ability to identify patients with abnormally high or low SVR of immense clinical value. In this study, a supervised classifier, based on Bayes' rule, is employed to classify a heterogeneous group of intensive care unit patients (N = 48) as being below (SVR < 900 dyn s cm(-5)), within (900 ? SVR ? 1200 dyn s cm(-5)) or above (SVR > 1200 dyn s cm(-5)) the clinically accepted range for normal SVR. Features derived from the finger photoplethysmogram (PPG) waveform and other routine cardiovascular measurements (heart rate and mean arterial pressure) were used as inputs to the classifier. In the construction of the classifier model, two techniques were used to approximate the class conditional probability densities--a single Gaussian distribution model (also known as discriminant analysis) and a non-parametric model using the Parzen window kernel density estimation method. An exhaustive feature search was performed to select a feature subset that maximized the performance indicator, Cohen's kappa coefficient (κ). The Gaussian model with multiple features achieved the best overall kappa coefficient (κ = 0.57), although the results from the non-parametric model were comparable (κ = 0.51). The optimum subset in the Gaussian model consisted of PPG waveform variability features, including the low-frequency to high-frequency ratio (LF/HF) and the normalized mid-frequency power (MF(NU)), in addition to the PPG pulse wave features, such as pulse width, peak-to-notch time, reflection index, and notch time ratio. The classifier performed particularly well in discriminating low SVR, with a sensitivity of 85%, specificity of 86%, positive predictive value of 88% and a negative predictive value of 82%. The results highlight the feasibility of deploying a multivariate statistical approach of SVR classification in the clinical setting, simply using a non-invasive and easy-to-measure PPG waveform signal.  相似文献   
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64.
BACKGROUND: Post-transplant lymphoproliferative disease (PTLD) is a serious, often fatal complication after solid organ transplantation. Primary Epstein-Barr virus (EBV) infection is the major risk factor for PTLD after lung transplantation, with 30% to 50% of EBV-naive patients who seroconvert and are diagnosed with PTLD. METHOD: In this study, we analyzed the incidence of PTLD in lung and heart-lung transplant recipients before 1996 (historic group) and then compared the impact of long-term anti-viral prophylaxis on the development of PTLD in EBV-seronegative recipients from January 1996 to December 2000 (post-1996 group). Routine induction therapy was not given after 1995. Patients not surviving 30 days, 25 of 341 (7.3%), were excluded. RESULTS: Historic group: PTLD developed in 7 of 167 (4.2%) patients, at a mean of 394 +/- 278 (95-885) days. The mortality was 87.5% at a mean follow-up of 186 +/- 207 (17-520) days after diagnosis. Post-1996 group: Eighteen of 149 (12.3%) patients were EBV seronegative at the time of transplantation, and of these 15 (83%) began receiving continuous anti-viral prophylaxis: acyclovir or valacyclovir or ganciclovir from January 1996. None of the EBV-seronegative recipients receiving continuous anti-viral prophylaxis were diagnosed with PTLD; however, 1 of 3 (33%) of the EBV-seronegative recipients who did not receive anti-viral prophylaxis were diagnosed with PTLD. In the EBV-seronegative recipients, no deaths had been caused by PTLD at a mean follow-up of 806 +/- 534 (39-1,084) days. In the post-1996 group, PTLD developed in 1 of 131 (0.76%) EBV-seropositive recipients. CONCLUSION: Continuous, specific anti-viral prophylaxis in high-risk EBV-seronegative recipients significantly reduces the incidence of PTLD after lung transplantation in the absence of induction therapy.  相似文献   
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66.
Achilles tendonitis or rupture are uncommon complications following the use of fluoroquinolones, with a reported incidence in the general population of 0.4%. The aims of the current study were to determine the incidence of Achilles tendon disease (ATD) in lung transplant recipients (LTR) and to identify risk factors. Questionnaires were sent to 150 LTR of whom 101 responded (67%). Twenty-two LTR (21.8%) experienced ATD (tendonitis 16, rupture six). The mean age of LTR who developed ATD was 52.9+/-6.1 yrs (range: 19-63.5 yrs). Only the use of ciprofloxacin was significantly associated with ATD (p<0.05). Age, sex, underlying disease necessitating transplantation, serum creatinine and cyclosporine levels were not associated with ATD. The association between ciprofloxacin and ATD was not dose related. Of the 72 LTR who had received ciprofloxacin, 20 (28%) developed ATD (tendonitis 15, rupture five). In patients receiving ciprofloxacin, there was no association between the mean cumulative dose of prednisolone and ATD. Tendon rupture occurred with a lower ciprofloxacin dosage than tendonitis and the mean recovery duration was significantly longer. To conclude, lung transplant recipients receiving ciprofloxacin are at significant risk of developing Achilles tendon disease. The association between ciprofloxacin and Achilles tendon disease appears to be idiosyncratic rather than dose-related.  相似文献   
67.
We have examined the changes in GABAA-mediated synaptic potentials recorded from CA3 pyramidal neurons in hippocampal slice cultures following application of zinc (Zn2+). Unlike 4-AP, Zn2+ did not enhance fast hyperpolarizing potentials but primarily enhanced depolarizing GABAA potentials. Zn2+ did not alter the postsynaptic response of pyramidal neurons to pressure applied GABA, consistent with previous reports that Zn2+ enhances the release of GABA from presynaptic terminals. To examine the role of local circuitry in the production of Zn2+ responses, we recorded from cultures maintained for 7–10 days following removal of the dentate and hilus to allow complete degeneration of the mossy fibers (DGX cultures). Zn2+ produced giant depolarizing potentials (GDPs) in DGX cultures that were identical to those in intact cultures. In contrast, the 4-AP response was dramatically altered in DGX cultures. In DGX cultures, Zn2+ co-applied with 4-AP appeared to inhibit the production of fast hyperpolarizing GABAA synaptic potentials produced by 4-AP alone. This inhibition of fast hyperpolarizing potentials suggests that Zn2+ may reduce the release of GABA onto pyramidal cell somata. These observations suggest that Zn2+ enhances GABA release from local circuit neurons that synapse onto pyramidal cell dendrites, and inhibits GABA release onto pyramidal cell somata.  相似文献   
68.
OBJECTIVE: To estimate prevalence of xerophthalmia and to assess dietary intake of vitamin A in Indian children aged under 6 y. DESIGN: Cross sectional study. STUDY SETTING: Urban slums under Urban Health Centre affiliated to Department of Preventive and Social Medicine, Government Medical College, Nagpur, India. PARTICIPANTS: The study included 1094 all children under 6 y of age, from two randomly selected urban slums. METHODS: Xerophthalmia was diagnosed on the basis of ocular signs and symptoms (WHO recommendations). Dietary intake of vitamin A was assessed by using one year recall method recommended by International Vitamin A Consultative Group. RESULTS: Prevalence of xerophthalmia was estimated to be 8.7%. Nine hundred and ninety-five (90.9%) study subjects were identified as inhabitants consuming dietary vitamin A at below recommended levels. (UPF score < 210). Five hundred and ninety-three (54.2%) study subjects were consuming dietary vitamin A at approximately less than 200 RE/d (UPF score < 120) while 402 (36.2%) were consuming approximately 200-300 RE/d (UPF score 120-210). The prevalence of xerophthalmia was found to be decreasing as the score of usual pattern of food consumption (UPF) increased. CONCLUSIONS: Children with a dietary intake represented by a UPF score of less than 120 were at high risk of developing xerophthalmia, whereas, those consuming vitamin A equal to a UPF score greater than 120 were at comparatively less risk despite being below the recommended levels.  相似文献   
69.
Primary spinal hydatid disease is rare and represents an uncommon but significant manifestation of hydatid disease. We report a case of primary intraspinal extradural hydatid cyst of the thoracic region causing spinal cord compression. The presenting symptoms were mostly atypical and the diagnosis was established preoperatively on the basis of magnetic resonance imaging. The patient underwent surgery resulting in complete recovery and is recurrence-free after 24 months follow-up.  相似文献   
70.
To maintain the hemodynamic stability of patient undergoing hemodialysis, this article proposes a novel model-based control methodology to regulate the changes in relative blood volume (RBV) and percentage change in heart rate (∆HR(%)) during hemodialysis by adjusting the ultrafiltration rate (UFR). The control algorithm uses model predictive control (MPC) to account for system variability and to explicitly handle the constraints on UFR. Linear state-space system with time-varying parameters is introduced to model the RBV and ∆HR. MPC was used to track the change in RBV and ∆HR to pre-defined reference trajectories. At each sampling instant, the system parameters are updated to get the best fitting into the parameterized model. Simulation results demonstrate that the system is able to regulate RBV and ∆HR to the reference by adjusting UFR while keeping it within practically realizable bounds. The results show that adjusting UFR may improve the stability of patient during dialysis when compared to conventional hemodialysis with constant UFR.  相似文献   
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