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51.

Purpose

Develop a multi-fiber tractography method that produces fast and robust results based on input data from a wide range of diffusion MRI protocols, including high angular resolution diffusion imaging, multi-shell imaging, and clinical diffusion spectrum imaging (DSI)

Methods

In a unified deconvolution framework for different types of diffusion MRI protocols, we represent fiber orientation distribution functions as higher-order tensors, which permits use of a novel positive definiteness constraint (H-psd) that makes estimation from noisy input more robust. The resulting directions are used for deterministic fiber tracking with branching.

Results

We quantify accuracy on simulated data, as well as condition numbers and computation times on clinical data. We qualitatively investigate the benefits when processing suboptimal data, and show direct comparisons to several state-of-the-art techniques.

Conclusion

The proposed method works faster than state-of-the-art approaches, achieves higher angular resolution on simulated data with known ground truth, and plausible results on clinical data. In addition to working with the same data as previous methods for multi-tissue deconvolution, it also supports DSI data.
  相似文献   
52.
Medium conditioned by tumor necrosis factor alpha (TNF-alpha)-stimulated polymorphonuclear leukocytes (PMN) (CM-TNF) suppresses PMN migration. Therefore, we wished to identify the agent(s) in CM-TNF that mediated antichemotactic activity. CM-TNF was fractionated by high-performance liquid chromatography, and one fraction with antichemotactic activity contained the bactericidal protein human neutrophil protein 1 (HNP-1). We showed that HNP-1 suppresses PMN migration to formyl-methionyl-leucyl-phenylalanine but not to interleukin 8.  相似文献   
53.
Kaletra (lopinavir/ritonavir)   总被引:1,自引:0,他引:1  
OBJECTIVE: To review the pharmacology, virology, pharmacokinetics, efficacy, safety, and clinical use of lopinavir/ritonavir (Kaletra, Abbott Laboratories). DATA SOURCES: English-language MEDLINE and AIDSline searches were performed (1966-July 2001) using lopinavir, ABT-378, and Kaletra as key words. Abstracts from infectious diseases and HIV scientific meetings were identified. Abbott Laboratories provided additional published and unpublished information. DATA EXTRACTION: All publications, meeting abstracts, and unpublished information were reviewed and relevant items included. In vitro and preclinical studies were included as well as Phase II and III clinical trials. DATA SYNTHESIS: Lopinavir/ritonavir is a fixed-dose protease inhibitor (PI) combination used for the treatment of HIV-1 infection. Lopinavir, the active component of this combination, is extensively metabolized by CYP3A4 and produces low systemic concentrations when used alone. Ritonavir potently inhibits CYP3A4 and is used to enhance the systemic exposure of lopinavir. This combination results in lopinavir concentrations that greatly exceed those necessary in vitro to inhibit both wild-type and PI-resistant HIV isolates. In clinical trials with antiretroviral na?ve and experienced patients, lopinavir/ritonavir was effective at suppressing HIV-RNA and increasing CD4+ T cell counts. Compared with other PIs, lopinavir/ritonavir may have advantages in the areas of pharmacokinetics, efficacy, and resistance. Toxicity, drug interactions, and medication adherence are important considerations surrounding its clinical use. CONCLUSIONS: Lopinavir/ritonavir is an effective option for the treatment of HIV-1-infected individuals when used in combination with other antiretroviral agents. It may be used as a component of initial therapy or salvage therapy; future studies will better define its place in therapy.  相似文献   
54.
Treatment with mammalian target of rapamycin inhibitors (mTORi) has been associated with an increased incidence of proteinuria after kidney transplantation as compared to other immunosuppressive agents. Proteinuria after mTORi use may occur in different clinical conditions and the precise mechanism remains unclear. The objective of this study was to investigate the related risk factors for proteinuria after mTORi treatment in kidney transplant recipients. This retrospective observational study population consisted of kidney transplant recipients followed up in a medical center in Southern Taiwan from January 1999 to April 2016. The baseline characteristics and transplantation-related profiles were collected at the time of enrollment. We examined risk factors for mTORi-associated proteinuria using a multivariate logistic regression analysis. P < .05 was considered as statistically significant. Hyperlipidemia and obesity at the initiation of mTORi treatment were strong predictors for proteinuria. Earlier identification of these risk factors may assist physicians in deciding the best candidate for mTORi conversion in order to optimize transplantation outcomes.  相似文献   
55.

Background

Comorbid conditions are important in the survival of kidney transplant recipients. The weights assigned to comorbidities to predict survival may vary based on the type of index disease and advances in the management of comorbidities. We aimed to develop a modified Charlson comorbidity index (CCI) in renal allograft recipients (mCCI-KT), thereby improving risk stratification for mortality.

Methods

A total of 3765 recipients in a multicenter cohort were included to develop a comorbidity score. The weights of the comorbidities, per the CCI, were recalibrated using a Cox proportional hazards model.

Results

Peripheral vascular disease, liver disease, myocardial infarction, and diabetes in the CCI were selected from the Cox proportional hazards model. Thus, the mCCI-KT included 4 comorbidities with recalibrated severity weights. Whereas the CCI did not discriminate for survival, the mCCI-KT provided significant discrimination for survival using the Kaplan-Meier method and Cox regression analysis. The mCCI-KT showed modest increases in c-statistics (0.54 vs 0.52, P = .001) and improved net mortality risk reclassification by 16.3% (95% confidence interval, 3.2–29.4; P = .015) relative to the CCI.

Conclusion

The mCCI-KT stratifies the risk for mortality in renal allograft recipients better than the CCI, suggesting that it may be a preferred index for use in clinical practice.  相似文献   
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60.

Introduction and hypothesis

We evaluated patients’ perception and satisfaction with nonsurgical pulsed magnetic stimulation (PMS) for treatment of female stress urinary incontinence (SUI) in a randomized, double-blind, sham-controlled trial.

Methods

Women with SUI (n = 120) were randomized to either active or sham PMS for 8 weeks (twice/week). Patients answered seven questions on their perception and acceptability, each measured on a 5-point Likert scale. Treatment satisfaction was assessed using two parameters: (i) the single-item question “Overall, please rate how satisfied you are with the treatment” and (ii) Patient Global Impression of Improvement (PGI-I). All adverse events were documented.

Results

A total of 115 patients completed treatments (active: n = 57, sham: n = 58). There were no significant differences between groups in all parameters regarding perception and acceptability (p > 0.05). In terms of treatment satisfaction, a significantly higher proportion of patients in the active group (n = 47/57, 82.4%) were either mostly or completely satisfied compared with those in the sham group (n = 27/58, 46.6%) ((p = 0.001). Similarly, a statistically significantly higher percentage of patients in the active group (n = 39/57, 68.4%) felt much or very much better compared with patients in the sham group (n = 11/58, 19.0%) as measured using the PGI-I (p < 0.001). Three (5.3%) patients in the active group and five (8.6%) in the sham group experienced adverse events (p = 0.72). Regardless of treatment arms, 109 (94.8%) patients would not consider surgical options even if they required further treatment for their condition.

Conclusion

PMS was well accepted, well tolerated, and resulted in a high treatment satisfaction among women with SUI.
  相似文献   
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