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61.
19F-nuclear magnetic resonance (NMR) has been extensively used in a drug-discovery programme to support the selection of candidates for further development. Data on an early lead compound, N-(4-fluorobenzyl)-5-hydroxy-1-methyl-2-(4-methylmorpholin-3-yl)-6-oxo-1,6-dihydropyrimidine-4-carboxamide (compound A (+)), and MK-0518 (N-(4-fluorobenzyl)-5-hydroxy-1-methyl-2-(1-methyl-1-{[(5-methyl-1,3,4-oxadiazol-2-yl)carbonyl]amino}ethyl)-6-oxo-1,6-dihydropyrimidine-4-carboxamide), a potent inhibitor of this series currently in phase III clinical trials, are described. The metabolic fate and excretion balance of compound A (+) and MK-0518 were investigated in rats and dogs following intravenous and oral dosing using a combination of 19F-NMR-monitored enzyme hydrolysis and solid-phase extraction chromatography and NMR spectroscopy (SPEC-NMR). Dosing with the 3H-labelled compound A (+) enabled the comparison of standard radiochemical analysis with 19F-NMR spectroscopy to obtain quantitative metabolism and excretion data. Both compounds were eliminated mainly by metabolism. The major metabolite identified in rat urine and bile and in dog urine was the 5-O-glucuronide.  相似文献   
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Cutaneous glomeruloid hemangioma is a hallmark of POEMS syndrome. These patients have elevated serum levels of vascular endothelial growth factor. The authors report an extracutaneous uterine glomeruloid hemangioma in an 82-year-old woman with a history of breast and endometrial carcinomas. Within the lumen of myometrial vessels, a lobular, glomeruloid proliferation of capillary-like CD31 and vascular endothelial growth factor receptor-1-positive endothelial cells was found. The capillary loops were lined by endothelial cells, most of them containing PAS-positive and immunoglobulin-positive eosinophilic hyaline globules (thanatosomes). This vascular proliferation was consistent with a glomeruloid hemangioma. Although an extracutaneous glomeruloid vascular proliferation has been found in the retroperitoneal adipose tissue in a patient with POEMS syndrome, this study reports what seems to be the first case of visceral glomeruloid hemangioma in a patient without POEMS syndrome. The authors hypothesize that the glomeruloid endothelial cell proliferation with vascular endothelial growth factor receptor-1 expression may be a paraneoplastic phenomenon.  相似文献   
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Buschke-Ollendorff syndrome (BOS) is a rare autosomal dominant genodermatosis caused by heterozygous mutations in LEMD3 and characterized by connective tissue nevi and sclerotic bone lesions known as osteopoikilosis. We report a family with three individuals affected by BOS, two of whom manifested clinical and histopathological peculiarities, presenting with a depressed indurated plaque as the main cutaneous manifestation instead of the classic connective tissue nevi. Notable elastorrhexis was present in both biopsies.  相似文献   
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Fifty-four cases of Achromobacter xylosoxidans bacteremia diagnosed over a 10-year period in patients from 2 months to 87 years of age were reviewed. Fifty-two episodes were nosocomial. The most frequent underlying condition was neoplasm (solid or hematological). The source of infection was a contaminated intravenous catheter in 35 patients (60%) and pneumonia in 6 patients. Eight (15%) patients died. The only risk factors significantly associated with mortality were age over 65 years and neutropenia. The results of in vitro susceptibility studies of the isolates showed that antibiotic therapy with antipseudomonal penicillins or carbapenems would be a reasonable choice. An epidemiological study conducted in the hemodialysis unit showed Achromobacter xylosoxidans in tap water and on the hands of two healthcare workers but not in the hemodialysis systems. Patients were probably contaminated when healthcare workers manipulated the intravenous catheters without wearing gloves.  相似文献   
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Lower‐extremity ischemia is a significant complication in children on femoral venoarterial extracorporeal membrane oxygenation (VA ECMO). Our institution currently routinely uses distal perfusion catheters (DPCs) in all femoral arterial cannulations in attempts to reduce ischemia. We performed a single‐center, retrospective review of pediatric patients supported with femoral VA ECMO from January 2005 to November 2015. The outcomes of patients with prophylactic DPC placement at cannulation (prophylactic DPC) were compared to a historical group with DPCs placed in response only to clinically evident ischemic changes (reactive DPC). Ischemic complication requiring invasive intervention (fasciotomy or amputation) was the primary outcome. Twenty‐nine patients underwent a total of 31 femoral arterial cannulations, 17 with prophylactic DPC and 14 with reactive DPC. Ischemic complications requiring invasive intervention developed in 2 of 17 (12%) prophylactic DPC patients versus 4 of 14 (29%) reactive DPC. In the reactive DPC group, 7 of 14 (50%) had ischemic changes postcannulation, six underwent DPC placement, and three out of six of these patients still required invasive intervention. One of the seven patients had ischemic changes, did not undergo DPC, and required amputation. While a greater percentage of patients in the prophylactic group was cannulated during extracorporeal cardiopulmonary resuscitation (ECPR), statistical significance was not otherwise demonstrated. We demonstrate feasibility of superficial femoral artery (SFA) access in pediatric patients. We note fewer ischemic complications with prophylactic DPC placement, and observe that salvaging a limb with a reactive DPC was only successful 50% of the time. Although there was no statistical difference in the primary outcome between the two groups, limitations and confounding factors include small sample size and a greater percentage of patients in the prophylactic DPC group cannulated with ECPR in progress.  相似文献   
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Objective: Early-onset fetal growth restriction is associated with poor pregnancy outcomes, but frequently is due to fetal structural or chromosomal abnormalities. The objective of this study was to determine outcomes in patients with early-onset fetal growth restriction without diagnosed fetal or genetic anomalies and to identify additional risk factors for poor outcomes in these patients.

Methods: This was retrospective cohort study of singleton pregnancies in women with early-onset growth restriction defined as a sonographic estimated fetal weight <10% diagnosed between 16–28 weeks’ gestation. We excluded all women with a fetal structural or chromosomal abnormality diagnosed prenatally. Data on pregnancy characteristics and outcomes were collected and analyzed for estimated fetal weight <10% and ≤5%. A nested case-control study within the cohort of patients with ongoing pregnancies was then performed to identify risk factors associated with poor pregnancy outcome using chi-squared test.

Results: One hundred forty-two patients were identified who met inclusion and exclusion criteria and 20 patients were found to have fetal structural or chromosomal abnormalities. In the remaining 122 patients, the incidence of intrauterine fetal demise was 5.7% and there were high rates of preterm birth <37 weeks (20%), birth weight <10% (59.3%), and gestational hypertension (14.1%). Later gestational age at diagnosis and the presence of echogenic bowel and abnormal initial umbilical artery Dopplers were associated with poor pregnancy outcome (22.56 versus 20.86 weeks, p?=?.046), (17.4 versus 2.2%, OR 9.68, 95%CI 1.65–56.73), and (35.3 versus 0%, OR 4.46, 95%CI 2.65–7.50) respectively.

Conclusions: Patients with early-onset fetal growth restriction with no fetal structural or genetic abnormality have a high risk of poor pregnancy outcomes. Gestational age at diagnosis and certain ultrasound findings are associated with poor pregnancy outcome.  相似文献   
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