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101.
The functional imaging technique of 18F‐fluoride positron emission tomography (18F‐PET) allows the noninvasive quantitative assessment of regional bone formation at any skeletal site, including the spine and hip. The aim of this study was to determine if 18F‐PET can be used as an early biomarker of treatment efficacy at the hip. Twenty‐seven treatment‐naive postmenopausal women with osteopenia were randomized to receive teriparatide and calcium and vitamin D (TPT group, n = 13) or calcium and vitamin D only (control group, n = 14). Subjects in the TPT group were treated with 20 µg/day teriparatide for 12 weeks. 18F‐PET scans of the proximal femur, pelvis, and lumbar spine were performed at baseline and 12 weeks. The plasma clearance of 18F‐fluoride to bone, Ki, a validated measurement of bone formation, was measured at four regions of the hip, lumbar spine, and pelvis. A significant increase in Ki was observed at all regions of interest (ROIs), including the total hip (+27%, p = 0.002), femoral neck (+25%, p = 0.040), hip trabecular ROI (+21%, p = 0.017), and hip cortical ROI (+51%, p = 0.001) in the TPT group. Significant increases in Ki in response to TPT were also observed at the lumbar spine (+18%, p = 0.001) and pelvis (+42%, p = 0.001). No significant changes in Ki were observed for the control group. Changes in BMD and bone turnover markers were consistent with previous trials of teriparatide. In conclusion, this is the first study to our knowledge to demonstrate that 18F‐PET can be used as an imaging biomarker for determining treatment efficacy at the hip as early as 12 weeks after initiation of therapy.  相似文献   
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This study explores the diagnostic utility of atrophy rates of the cingulate gyrus, its subdivisions and the hippocampus in Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD). Regions were manually outlined on MR images of a group of pathologically or genetically confirmed patients with AD (n=19), FTLD (n=8) and age-matched controls (n=11). Mean (S.D.) atrophy rates (%year(-1)) in the cingulate in controls, AD and FTLD were -0.3 (1.2), 5.9 (3.5), and 8.6 (4.1), respectively. Hippocampal atrophy rates in controls, AD and FTLD were -0.1 (0.8), 3.4 (2.2), and 5.2 (5.4), respectively. Atrophy rates were significantly higher in the cingulate and hippocampi in AD and FTLD compared with controls (p<0.01). There was evidence of a difference in trends of atrophy in the cingulate (more anterior in FTLD and more posterior in AD) between the disease groups (p=0.03). Cingulate atrophy rates discriminated perfectly between FTLD and controls. Significantly better discrimination between AD and controls was obtained by hippocampal rather than cingulate rates. In conclusion, cingulate atrophy is as significant a feature of AD and FTLD as hippocampal atrophy.  相似文献   
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AIMS: To compare immunohistochemical staining for oestrogen receptor, progesterone receptor and HER-2 between core biopsy and matched subsequent excisional specimens. METHODS: One hundred consecutive core biopsy cases and subsequent excisional specimens were retrieved and immunohistochemical staining performed. Proportion and intensity of staining for hormone receptors and HercepTest score were recorded for each case in a blinded fashion by the authors. RESULTS: Overall hormone receptor status was concordant between cores and excisions in 96.9% of cases. ER status was concordant between the core and excision in 95.8% of cases. The intensity of staining for ER was similar in both core and excision specimens. PR status was concordant in cores and excisions in 90.3% of cases. There was weaker PR staining in the excisional specimens when compared with the cores. HER-2 status was concordant in cores and excisions in 86.6% of cases. CONCLUSIONS: Hormone receptor staining produced similar results on core and excisional specimens, although a small number of additional hormone receptor positive cases could be detected by performing staining on a previously received core in the case of a negative result on the excisional specimen. HER-2 staining is less reproducible between cores and excisions, but the clinical significance of this observation remains to be tested.  相似文献   
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Management of transverse maxillary discrepancies poses treatment planning and postoperative challenges for surgeons and orthodontists. Multiple position papers have been written on the subject covering various aspects of nonoperative and surgical treatment and timing and stability issues. This article seeks not to propagate the debate of which procedure is better but rather to discuss appropriate indications for each in addition to their respective benefits and pitfalls. An historical perspective and the technical aspects of performing each operation are reviewed.  相似文献   
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The present study examined self-concealment as a possible mediator in the relationship between perfectionism and distress. The study also explored whether willingness to disclose differed depending on whether the disclosure was to a friend, family member, or counselor. One hundred and sixteen undergraduate women were administered the Multidimensional Perfectionism Scale, the Self-Concealment Scale, the Hopkins Symptom Checklist-21, and the College Issues Questionnaire. Correlational analyses indicated that maladaptive perfectionism, self-concealment, and distress were all highly related. Path analysis indicated that self-concealment mediated the relationship between maladaptive perfectionism and distress. Willingness to discuss issues with family and friends was negatively correlated with maladaptive perfectionism and self-concealment, but unrelated to distress. These results indicate that a tendency to conceal negative personal information may be a significant contributor to the psychological distress experienced by those with maladaptive perfectionism.  相似文献   
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