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951.
Peripartum cardiomyopathy   总被引:2,自引:0,他引:2  
Peripartum cardiomyopathy (PPCM) is a rare, idiopathic, life-threatening disease of late pregnancy and early puerperium, occurring in patients with previously healthy hearts. Risk factors include multiparity, age>30 years, African American race, multiple pregnancies, obesity, hypertension, and toxemia. Signs and symptoms of PPCM resemble systolic heart failure, and it is diagnosed by exclusion. An echocardiogram typically reveals an ejection fraction of <45% and/or fractional shortening of <30%, along with a left ventricular end-diastolic dimension>2.7 cm/m2 of body surface area. Early diagnosis and treatment are important for a successful outcome. Management is similar to other forms of systolic heart failure. Patients with PPCM are at high risk of thromboembolism, and therefore anticoagulation therapy should be considered. The prognosis is variable, ranging from complete recovery, to worsening heart failure requiring cardiac transplantation, or death. Future pregnancies are often discouraged because of the high mortality rate and risk of recurrence.  相似文献   
952.
We evaluated the clonogenic survival, membrane permeability, metabolic activity (XTT reduction), and apoptosis (FLICA binding) of Cryptococcus neoformans cells subjected to gamma rays from an external source, and beta and alpha particles delivered to fungal cells by capsule-specific antibody. We found that gamma, beta, and alpha radiation affected cells through different pathways.  相似文献   
953.
We describe a simple two-photon fluorescence imaging strategy, called targeted path scanning (TPS), to monitor the dynamics of spatially extended neuronal networks with high spatiotemporal resolution. Our strategy combines the advantages of mirror-based scanning, minimized dead time, ease of implementation, and compatibility with high-resolution low-magnification objectives. To demonstrate the performance of TPS, we monitor the calcium dynamics distributed across an entire juvenile rat hippocampus (>1.5mm), at scan rates of 100 Hz, with single cell resolution and single action potential sensitivity. Our strategy for fast, efficient two-photon microscopy over spatially extended regions provides a particularly attractive solution for monitoring neuronal population activity in thick tissue, without sacrificing the signal-to-noise ratio or high spatial resolution associated with standard two-photon microscopy. Finally, we provide the code to make our technique generally available.  相似文献   
954.
Although current evidence supporting a more precise strategy for identifying patients at highest risk for sudden cardiac death (SCD) is sparse, strategies for translating existing and future evidence into clinical practice and policy are needed today. A great many unanswered questions exist. Examples include the following: At what level of risk for SCD should we pursue further testing or therapy? How should clinical strategies ethically and economically balance alternative outcomes? How can we best translate optimal strategies into clinical practice so as to prevent tomorrow's SCDs? On July 20 and 21, 2006, a group of individuals with expertise in clinical cardiovascular medicine, biostatistics, economics, and health policy was joined by government (Food and Drug Administration; Centers for Medicare and Medicaid Services; National Heart, Lung, and Blood Institute; Agency for Healthcare Research and Quality), professional societies (Heart Rhythm Society), and industry to discuss strategies for risk assessment and prevention of SCD. The meeting was organized by the Duke Center for the Prevention of Sudden Cardiac Death and the Duke Clinical Research Institute. This article, the second of 2 documents, summarizes the policy discussions of that meeting, discusses an analytic framework for evaluating the risks and benefits associated with SCD prevention and risk stratification, and addresses the translation of SCD risk assessment strategies into practice and policy.  相似文献   
955.
We report on a rare case of hypoxanthine guanine phosphoribosyl transferase (HGPRT) deficiency that presented in the newborn period with acute renal failure (ARF). The clinical diagnosis was made on the basis of non-oliguric ARF and evidence of crystal nephropathy on renal biopsy. HGPRT deficiency was eventually confirmed by enzymatic and genetic testing, showing a novel point mutation, 293 A>G. Immediate treatment consisted of peritoneal dialysis with, initially, lactate- then bicarbonate-buffered 1.36% glucose solution together with oral administration of allopurinol. Follow-up after more than 4 years continued to show hyper-echogenic kidneys with almost normal renal glomerular function. There continues to be no neurobehavioural abnormalities.  相似文献   
956.
957.
Color Doppler Imaging Predicts Portal Invasion by Pancreatic Adenocarcinoma   总被引:9,自引:0,他引:9  
Background Tumor infiltration of the intima of the portal vein (PV) and superior mesenteric vein (SMV) by pancreatic adenocarcinoma is classically considered a criterion for unsuitability for resection and poor prognosis. This study was performed to evaluate modern color duplex imaging (CDI) for the assessment of PV/SMV infiltration by pancreatic adenocarcinomas. Method From 1994 to 2005, Whipple’s procedure or pylorus-preserving pancreato-duodenectomy (PPPD) was performed in 303 patients with pancreatic adenocarcinoma; 35 of these underwent partial PV/SMV resection. Applying a previously reported CDI score, we evaluated the integrity of the echogenic border layer between the vein and tumor (mural demarcation) and maximum blood flow velocity (V max) in the PV segment in contact with the tumor. The results were compared to the final histological findings in the resected venous walls. Results CDI findings correlated well with the histological invasion grades. By measuring V max and evaluating mural demarcation, we observed a sensitivity of 66.7% and 100% and a specificity of 98.3% and 93.9%, respectively, in predicting full thickness vein invasion, including the intima. V max above 80 cm/s and lack of mural demarcation were predictors of PV/SMV invasion. The postoperative survival rates depended on the depth of tumor infiltration into the PV/SMV. Conclusions Modern CDI is a reliable and valid technique for evaluation of morphological and hemodynamic parameters in the portal vein segment adjacent to pancreatic adenocarcinoma. Maximal blood-flow velocity in the portal segment in contact with the tumor and absence of the echogenic vessel-parenchymal sonographic interface are parameters predictive of tumor infiltration of the portal intima.  相似文献   
958.
959.
Retained fecalith after an appendectomy is an uncommon complication frequently associated with intra-abdominal abscess. Treatment options include percutaneous, open, or laparoscopic drainage of the abscess and retrieval of the fecalith, as antibiotics and drainage alone are usually insufficient. Laparoscopy offers the advantages of enhanced visualization of the abdomen, improved cosmesis, and a quicker return to normal daily activities. The principles of laparoscopic treatment include the careful identification of all anatomic landmarks, as the abscesses are frequently adherent to intra-abdominal structures compromising the safety of the operation. In this paper, we present 2 cases of laparoscopic drainage of an intra-abdominal abscess with retrieval of a fecalith in pediatric patients 1 and 6 weeks after an initial appendectomy and a review the literature.  相似文献   
960.
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