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BACKGROUND: The main benefits of mammography come from regular on-schedule screening. However, few studies have examined interventions to achieve repeat screening. SETTING AND PARTICIPANTS: Participants were women aged 50 to 74, recruited through one setting in Rhode Island and another in North Carolina. Participants had a mammogram already scheduled at recruitment, and had to keep that appointment in order to be eligible for the repeat mammography intervention. A total of 1614 women were in the intervention sample. DESIGN: A four-group randomized design was used: Group 1, a simple reminder letter; Group 2, a 2-month, tailored, stepped intervention delivered 2 months after the completed mammogram; Group 3, a 10-month, tailored, stepped intervention delivered 2 months before the repeat mammogram was due; and Group 4, self-choice of one of the above three strategies. INTERVENTION: The intervention took place between June 1996 and May 1997. The reminder letter and two levels of the stepped intervention were delivered by mail. The third level of the stepped strategy was a counselor telephone call. Groups 2 and 3 were identical, except for timing. OUTCOME MEASURE: Obtaining the next due mammogram within 15 months, based on clinic records. RESULTS: There were no statistically significant differences among the four groups, both in the total sample and at the two sites separately. CONCLUSIONS: On average, a simple reminder may be as effective as more complex strategies for women with a prior on-schedule exam. However, attention is still needed to identify women at risk of lapsing from screening. Some women may require more-intensive interventions.  相似文献   
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Cutaneous leishmaniasis (CL) manifests as localized skin lesions, which lead to significant tissue destruction and disfigurement. In the Yucatan Peninsula, Mayan traditional healers use Pentalinon andrieuxii Muell.‐Arg. (Apocynaceae) roots for the topical treatment of CL. Here, we studied the effect of P. andrieuxii root hexane extract (PARE) on the parasites and host cells in vitro and examined its efficacy in the topical treatment of CL caused by Leishmania mexicana. PARE exhibited potent antiparasitic activity in vitro against promastigotes as well as amastigotes residing in macrophages. Electron microscopy of PARE‐treated parasites revealed direct membrane damage. PARE also activated nuclear factor kappaB and enhanced interferon‐γ receptor and MHC class II expression and TNF‐α production in macrophages. In addition, PARE induced production of the Th1 promoting cytokine IL‐12 in dendritic cells as well as enhanced expression of the co‐stimulatory molecules CD40, CD80, and CD86. In vivo studies showed that L. mexicana‐infected mice treated by topical application of PARE resulted in the significant reduction in lesion size and parasite burden compared to controls. These findings indicate that PARE could be used as an alternative therapy for the topical treatment of CL. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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YC Hsu  CH Hsu  WY Tseng 《NeuroImage》2012,63(2):818-834
Spatial transformation for diffusion spectrum imaging (DSI) is an important step for group analyses of DSI datasets. In this study, we developed a transformation method for DSI datasets under the framework of large deformation diffeomorphic metric mapping (LDDMM), which is termed LDDMM-DSI. The proposed method made use of the fact that a DSI dataset is 6D, and generalized the original 2D/3D LDDMM algorithm to the 6D case with some modifications made for the DSI datasets. In this manner, the conventional reorientation problem that arises from transforming diffusion-weighted datasets was avoided by making the DSI datasets capable of being freely deformed in the q-space. The algorithm treated the data-matching task as a variational problem under the LDDMM framework and sought optimal velocity fields from which the generated transformations were diffeomorphic and the transformation curve was a geodesic. The mathematical materials and numerical implementation are detailed in the paper, and experiments were performed to analyze the proposed method on real brain DSI datasets. The results showed that the method was capable of registering different DSI datasets in both global structural shapes and local diffusion profiles. In conclusion, the proposed method can facilitate group analyses of DSI datasets and the generation of a DSI template.  相似文献   
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Background

Despite overlapping features of T‐cell lymphoblastic lymphoma (T‐LLy) and T‐cell acute lymphoblastic leukemia (T‐ALL), which respond favorably to T‐ALL treatment, clinical and biological differences exist. We retrospectively assessed the prevalence of submicroscopic bone marrow (BM) minimal disseminated disease (MDD) at diagnosis and the early response to treatment (minimal residual disease—MRD) and their prognostic significance in 17 children with stage III T‐LLy treated according to Berlin‐Frankfurt‐Munster (BFM) non‐Hodgkin lymphoma protocols.

Procedure

Four‐color flow cytometry (FC) was used for lymphoma associated immunophenotype and real‐time quantitative polymerase chain reaction (RQ‐PCR) for T‐cell receptor (TCR β/δ/γ) gene rearrangements with at least 0.01% sensitivity.

Results

Two markers per patient were identified in all cases using FC and in 80% using RQ‐PCR. BM MDD at diagnosis of ≥0.01% was detected by FC and RQ‐PCR in 88% and 80% of patients, respectively, and by at least one of the methods in all patients. A significant correlation was achieved between the methods by Pearson correlation analysis (P = 0.004). MRD levels significantly decreased to very low levels on day 33 in 9 out of 10 patients studied. The only patient that remained positive relapsed.

Conclusions

MDD was prevalent in stage III T‐LLy, for which we could not prove a prognostic significance in the context of ALL‐like treatment. This study shows that both FC and RQ‐PCR methods are efficient for MDD and MRD analyses in T‐LLy. Pediatr Blood Cancer 2009;52:20–25. © 2008 Wiley‐Liss, Inc.  相似文献   
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