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During aging, changes in endosteal and periosteal boundaries of cortical bone occur that differ between men and women. We here develop a new procedure that uses high-resolution peripheral quantitative CT (HR-pQCT) imaging and 3D registration to identify such changes within the timescale of longitudinal studies. A first goal was to test the sensitivity of the approach. A second goal was to assess differences in periosteal/endosteal expansion over time between men and women. Rigid 3D registration was used to transform baseline and all follow-up (FU) images to a common reference configuration for which the region consisting of complete slices (largest common height) was determined. Periosteal and endosteal contours were transformed to the reference position to determine the net periosteal and endosteal expansion distances. To test the sensitivity, images from a short-term reproducibility study were used (15 female, aged 21 to 47 years, scanned three times). To test differences between men and women, images from a subset of the Geneva Retirees Cohort were used (248 female, 61 male, average age 65 years, 3.5 and 7 years FU). The sensitivity study indicated a least significant change for detecting periosteal/endosteal expansion of 41/31 microns for the radius and 17/26 microns for the tibia. Results of the cohort study showed significant net endosteal retraction only in females at the radius and tibia after 3.5 years (38.0 and 38.4 microns, respectively) that further increased at 7 years FU (70.4 and 70.8 microns, respectively). No significant net periosteal changes were found for males or females at 7 years. The results demonstrate that it is possible to measure changes in endosteal contours in longitudinal studies within several years. For the investigated cohort, significant endosteal retraction was found in females but not in males. Whether these changes in cortical geometry are related to fracture risk remains to be investigated in larger cohorts © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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INTRODUCTION: Mortality due to breast cancer has been reported to be the same or even lower in HRT users than in non-users. This has been attributed to earlier diagnosis and to better prognosis. Nevertheless, more advanced disease in HRT users was reported recently by the Women's Health Initiative (WHI) study. The objective of this study was to assess, using a systematic review of current literature, whether the data of the WHI study are in contradiction to observational data. METHODS: We selected 25 studies, for which we evaluated the methodology, the characteristics of the studied populations, confounding breast cancer risk factors and prognostic indicators. RESULTS: The WHI study, showing a worsening of some prognostic parameters, is in contradiction to most published observational studies. Most observational studies are retrospective, not well matched and did not consider most confounding factors. Their methodology and selection criteria varied considerably and the number of patients was often small. No differences in the distributions of histology, grade or steroid receptors were observed in the WHI trial, while this was the case in some of the observational studies. Other parameters (S phase, protein Neu, Bcl-2 gene, protein p53 and E-cadherin, cathepsin D) were not reported in the WHI trial. CONCLUSIONS: In view of these data, the current clinical message to patients should be changed: one can no longer declare that breast cancers developed while using HRT are of better prognosis.  相似文献   
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Protein tyrosine kinases (PTKs) are a family of enzymes sharing a highly conserved catalytic domain which phosphorylates substrate proteins on tyrosine residues. PTKs play a major role in the transduction of the mitogenic signal and are involved in the control of cell proliferation, differentiation, and transformation processes. PTKs can be subdivided into two major types: membrane associated PTKs consisting essentially of growth factor receptors (receptor tyrosine kinases or RTKs) and cytosolic PTKs involved in the intracellular transduction of mitogenic and differentiation signals. From January 1988 to January 1992, PTK activity was assayed in cytosolic fractions prepared from 350 T1-T2, N0-N1 M0, breast carcinomas. Enzymatic activity was measured using phosphate transfer from [32P]-ATP to poly-Glu-Tyr as an artificial substrate. According to our previously reported pilot study, we chose a cut-off value of 12 pmol32P incorporated min–1 mg–1 protein, corresponding to the median value. We found positive PTK levels ( 12 pmol/min/mg) to be correlated with a loss of differentiation according to Scarff-Bloom grade (p < 0.001), negative PR (p = 0.03) and ER status (p = 0.04). With a median follow-up of 30 months (0–82), patients with a positive PTK level presented a smaller 3-year disease free survival than in the PTK negative group of patients (p = 0.07). In Cox multivariate analysis including pT, pN, Scarff-Bloom grade, PR and ER, PTK activity does not emerge as a significant prognostic factor.  相似文献   
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PURPOSE: Scarce information is available on the brain penetration of temozolomide (TMZ), although this novel methylating agent is mainly used for the treatment of malignant brain tumors. The purpose was to assess TMZ pharmacokinetics in plasma and cerebrospinal fluid (CSF) along with its inter-individual variability, to characterize covariates and to explore relationships between systemic or cerebral drug exposure and clinical outcomes. EXPERIMENTAL DESIGN: TMZ levels were measured by high-performance liquid chromatography in plasma and CSF samples from 35 patients with newly diagnosed or recurrent malignant gliomas. The population pharmacokinetic analysis was performed with nonlinear mixed-effect modeling software. Drug exposure, defined by the area under the concentration-time curve (AUC) in plasma and CSF, was estimated for each patient and correlated with toxicity, survival, and progression-free survival. RESULTS: A three-compartment model with first-order absorption and transfer rates between plasma and CSF described the data appropriately. Oral clearance was 10 liter/h; volume of distribution (V(D)), 30.3 liters; absorption constant rate, 5.8 h(-1); elimination half-time, 2.1 h; transfer rate from plasma to CSF (K(plasma-->CSF)), 7.2 x 10(-4)h(-1) and the backwards rate, 0.76 h(-1). Body surface area significantly influenced both clearance and V(D), and clearance was sex dependent. The AUC(CSF) corresponded to 20% of the AUC(plasma). A trend toward an increased K(plasma-->CSF) of 15% was observed in case of concomitant radiochemotherapy. No significant correlations between AUC in plasma or CSF and toxicity, survival, or progression-free survival were apparent after deduction of dose-effect. CONCLUSIONS: This is the first human pharmacokinetic study on TMZ to quantify CSF penetration. The AUC(CSF)/AUC(plasma) ratio was 20%. Systemic or cerebral exposures are not better predictors than the cumulative dose alone for both efficacy and safety.  相似文献   
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PURPOSE: Although there is wide recognition of the usefulness of improving physicians' communication skills, no studies have yet assessed the efficacy of post-training consolidation workshops. This study aims to assess the efficacy of six 3-hour consolidation workshops conducted after a 2.5-day basic training program. METHODS: Physicians, after attending the basic training program, were randomly assigned to consolidation workshops or to a waiting list. Training efficacy was assessed through simulated and actual patient interviews that were audiotaped at baseline and after consolidation workshops for the consolidation-workshop group, and approximately 5 months after the end of basic training for the waiting-list group. Communication skills were assessed according to the Cancer Research Campaign Workshop Evaluation Manual. Patients' perceptions of communication skills improvement were assessed using a 14-item questionnaire. RESULTS: Sixty-three physicians completed the training program. Communication skills improved significantly more in the consolidation-workshop group compared with the waiting-list group. In simulated interviews, group-by-time repeated measures analysis of variance showed a significant increase in open and open directive questions (P =.014) and utterances alerting patients to reality (P =.049), as well as a significant decrease in premature reassurance (P =.042). In actual patient interviews, results revealed a significant increase in acknowledgements (P =.022) and empathic statements (P =.009), in educated guesses (P =.041), and in negotiations (P =.008). Patients interacting with physicians who benefited from consolidation workshops reported higher scores concerning their physicians' understanding of their disease (P =.004). CONCLUSION: Consolidation workshops further improve a communication skills training program's efficacy and facilitate the transfer of acquired skills to clinical practice.  相似文献   
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Exostoses of the external auditory canal can occur in patients living in coastal, southern California communities with a history of cold-water aquatic activities such as ocean surfing and swimming. Although most canal exostoses are asymptomatic, patients with canal obstruction greater than 80% can have recurrent episodes of external otitis and a related conductive hearing loss. In most cases, medical treatment resolves the symptomatic external otitis and related hearing loss. Patients recalcitrant to medical treatment are candidates for surgical removal of the exostoses. This report reviews the authors' surgical experience with 18 patients (27 ears) who have undergone surgical removal of exostoses. Their preferred surgical technique of transmeatal removal of exostoses with a specialized mallet and thin chisel under local anesthesia is described.  相似文献   
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Parkinson's disease is primarily considered a motor disease characterized by rest tremor, rigidity, bradykinesia and postural disturbances. However, neuropsychiatric complications, including mood and anxiety disorders, fatigue, apathy, psychosis, cognitive impairment, dementia, sleep disorders and addictions, frequently complicate the course of the illness. The pathophysiologic features of these complications are multifaceted and include neuropathophysiologic changes of a degenerative disease, exposure to antiparkinsonian treatments and emotional reactions to having a disabling chronic illness. Changes in mental status have profound implications for the well-being of patients with Parkinson's disease and of their caregivers. Treatment is often efficacious but becomes a challenge in advanced stages of Parkinson's disease. In this article, we review the key clinical features of neuropsychiatric complications in Parkinson's disease as well as what is known about their epidemiologic characteristics, risk factors, pathophysiologic features and management.  相似文献   
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