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991.
992.
The rituximab extended schedule or retreatment trial (RESORT; E4402) was a phase 3 randomized prospective trial comparing maintenance rituximab (MR) versus a retreatment (RR) dosing strategy in asymptomatic, low tumour burden indolent lymphoma. A planned exploratory sub‐study compared the two strategies for small lymphocytic (SLL) and marginal zone lymphomas (MZL). Patients responding to rituximab weekly × 4 were randomized to MR (single dose rituximab every 3 months until treatment failure) or RR (rituximab weekly × 4) at the time of each progression until treatment failure. The primary endpoint was time to treatment failure (TTTF). Patients with SLL (n = 57), MZL (n = 71) and unclassifiable small B‐cell lymphoma (n = 3) received induction rituximab. The overall response rate (ORR) was 40% [95% confidence interval (CI) 31–49%; SLL ORR 22·8%; MZL ORR 52·1%]; all 52 responders were randomized. At a median of 4·3 years from randomization, treatment failure occurred in 18/23 RR and 15/29 MR. The median TTTF was 1·4 years for RR and 4·8 years for MR (P = 0·012); median time to first cytotoxic therapy was 6·3 years for RR and not reached for MR (P = 0·0002). Survival did not differ (P = 0·72). In low tumour burden SLL and MZL patients responding to rituximab induction, MR significantly improved TTTF as compared with RR.  相似文献   
993.

Background:

We retrospectively studied the impact of glucose meter error on the efficacy of glycemic control after cardiovascular surgery.

Method:

Adult patients undergoing intravenous insulin glycemic control therapy after cardiovascular surgery, with 12-24 consecutive glucose meter measurements used to make insulin dosing decisions, had glucose values analyzed to determine glycemic variability by both standard deviation (SD) and continuous overall net glycemic action (CONGA), and percentage glucose values in target glucose range (110-150 mg/dL). Information was recorded for 70 patients during each of 2 periods, with different glucose meters used to measure glucose and dose insulin during each period but no other changes to the glycemic control protocol. Accuracy and precision of each meter were also compared using whole blood specimens from ICU patients.

Results:

Glucose meter 1 (GM1) had median bias of 11 mg/dL compared to a laboratory reference method, while glucose meter 2 (GM2) had a median bias of 1 mg/dL. GM1 and GM2 differed little in precision (CV = 2.0% and 2.7%, respectively). Compared to the period when GM1 was used to make insulin dosing decisions, patients whose insulin dose was managed by GM2 demonstrated reduced glycemic variability as measured by both SD (13.7 vs 21.6 mg/dL, P < .0001) and CONGA (13.5 vs 19.4 mg/dL, P < .0001) and increased percentage glucose values in target range (74.5 vs 66.7%, P = .002).

Conclusions:

Decreasing glucose meter error (bias) was associated with decreased glycemic variability and increased percentage of values in target glucose range for patients placed on intravenous insulin therapy following cardiovascular surgery.  相似文献   
994.

Background

A suspicious occlusal carious lesion (SOCL) can be defined as a lesion with no cavitation and no radiographic radiolucency but for which caries is suspected. The authors evaluated whether using a device changed the percentage of SOCLs that were opened surgically and, among those SOCLs that were opened, the proportion that had penetrated into dentin.

Methods

Eighty-two dentists participated. In phase 1 of the study, dentists identified approximately 20 SOCLs, obtained patient consent, and recorded information about the lesion, treatment or treatments, and depth, if opened. Dentists were then randomly assigned into 1 of 3 groups: no device, DIAGNOdent (KaVo), and Spectra (Air Techniques). In phase 2, dentists enrolled approximately 20 additional patients and recorded the same phase 1 information while using the assigned device to help make their treatment decisions. A mixed-model logistic regression was used to determine any differences after randomization in the proportion of lesions opened and, if opened, the proportion of lesions that penetrated into dentin.

Results

A total of 1,500 SOCLs were enrolled in each phase. No statistically significant difference was found in the change in proportion of lesions receiving invasive treatment from phase 1 to phase 2 across the 3 groups (P = .33) or in the change in proportion of percentage of opened lesions that extended into dentin (P = .31).

Conclusion

Caries-detecting devices in the study did not change substantially dentists’ decisions to intervene or the accuracy of the intervention decision in predicting lesion penetration into dentin.

Practical Implications

The caries-detecting devices tested may not improve dentists’ clinical decision making for SOCLs.  相似文献   
995.
BackgroundStratification of individuals at risk for chronic kidney disease may allow optimization of preventive measures to reduce disease incidence and complications. We sought to develop a risk score that estimates an individual's absolute risk of incident chronic kidney disease.MethodsFramingham Heart Study participants free of baseline chronic kidney disease, who attended a baseline examination in 1995-1998 and follow-up in 2005-2008, were included in the analysis (n = 2490). Chronic kidney disease was defined as an estimated glomerular filtration rate <60 mL/min/1.73m2 using the Modification of Diet in Renal Disease equation. Participants were assessed for the development of chronic kidney disease at 10 years follow-up. Stepwise logistic regression was used to identify chronic kidney disease risk factors, and these were used to construct a risk score predicting 10-year chronic kidney disease risk. Performance characteristics were assessed using calibration and discrimination measures. The final model was externally validated in the bi-ethnic Atherosclerosis Risk in Communities Study (n = 1777).ResultsThere were 1171 men and 1319 women at baseline, and the mean age was 57.1 years. At follow-up, 9.2% (n = 229) had developed chronic kidney disease. Age, diabetes, hypertension, baseline estimated glomerular filtration rate, and albuminuria were independently associated with incident chronic kidney disease (P <.05), and these covariates were incorporated into a risk function (c-statistic 0.813). In external validation in the ARIC study, the c-statistic was 0.74 in whites (n = 1353) and 0.75 in blacks (n = 424).ConclusionRisk stratification for chronic kidney disease is achievable using a risk score derived from clinical factors that are readily accessible in primary care. The utility of this score in identifying individuals in the community at high risk of chronic kidney disease warrants further investigation.  相似文献   
996.

Background.

We used sensitive spectroscopic techniques to measure changes in Band 3 oligomeric state during storage of packed red blood cells (RBC); these changes were compared to metabolic changes, RBC morphology, cholesterol and membrane protein loss, phospholipid reorganisation of the RBC membrane, and peroxidation of membrane lipid. The aim of the study was to temporally sequence major biochemical events occurring during cold storage, in order to determine which changes may underlie the structural defects in stored RBC.

Materials and methods.

Fifteen RBC units were collected from normal volunteers and stored under standard blood bank conditions; both metabolic changes and lipid parameters were measured by multiple novel assays including a new mass spectrometric measurement of isoprostane (lipid peroxidation) and flow cytometric assessment of CD47 expression. Band 3 oligomeric state was assessed by time-resolved phosphorescence anisotropy, and RBC morphology by microscopy of glutaraldehyde-fixed RBC.

Results.

Extracellular pH decreased and extracellular potassium increased rapidly during cold storage. Band 3 on the RBC membrane aggregated into large oligomers early in the storage period and coincident with changes in RBC morphology. Membrane lipid changes, including loss of unesterified cholesterol, lipid peroxidation and expression of CD47, also changed early during the storage period. In contrast loss of acetylcholinesterase activity and haemolysis of RBC occurred late during storage.

Discussion.

Our results demonstrate that changes in the macromolecular organisation of membrane proteins on the RBC occur early in storage and suggest that lipid peroxidation and/or oxidative damage to the membrane are responsible for irreversible morphological changes and loss of function during red cell storage.  相似文献   
997.
Marfan syndrome is associated with a high incidence of aortic root aneurysm and life-threatening aortic dissection. With the successful use of surgical aortic root replacement, dissection-related mortality has been significantly reduced. We present the case of a patient with Marfan syndrome who presented with heart failure secondary to an unusual graft-related complication 14 years after a Bentall procedure. Investigations revealed a supra-aortic stenosis resulting from a kink in the Bentall graft caused by pressure from an expanding aortic arch aneurysm. The patient underwent surgery with improvement in his ejection fraction and heart failure symptoms.  相似文献   
998.
Compulsive behavior is a debilitating clinical feature of many forms of neuropsychiatric disease, including Tourette syndrome, obsessive-compulsive spectrum disorders, eating disorders, and autism. Although several studies link striatal dysfunction to compulsivity, the pathophysiology remains poorly understood. Here, we show that both constitutive and induced genetic deletion of the gene encoding the melanocortin 4 receptor (MC4R), as well as pharmacologic inhibition of MC4R signaling, normalize compulsive grooming and striatal electrophysiologic impairments in synapse-associated protein 90/postsynaptic density protein 95-associated protein 3 (SAPAP3)-null mice, a model of human obsessive-compulsive disorder. Unexpectedly, genetic deletion of SAPAP3 restores normal weight and metabolic features of MC4R-null mice, a model of human obesity. Our findings offer insights into the pathophysiology and treatment of both compulsive behavior and eating disorders.  相似文献   
999.
The standard recommendation for treating chronic osteomyelitis is 6 weeks of parenteral antibiotic therapy. However, oral antibiotics are available that achieve adequate levels in bone, and there are now more published studies of oral than parenteral antibiotic therapy for patients with chronic osteomyelitis. Oral and parenteral therapies achieve similar cure rates; however, oral therapy avoids risks associated with intravenous catheters and is generally less expensive, making it a reasonable choice for osteomyelitis caused by susceptible organisms. Addition of adjunctive rifampin to other antibiotics may improve cure rates. The optimal duration of therapy for chronic osteomyelitis remains uncertain. There is no evidence that antibiotic therapy for >4-6 weeks improves outcomes compared with shorter regimens. In view of concerns about encouraging antibiotic resistance to unnecessarily prolonged treatment, defining the optimal route and duration of antibiotic therapy and the role of surgical debridement in treating chronic osteomyelitis are important, unmet needs.  相似文献   
1000.
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