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31.
An optically transparent tissue-mimicking (TM) phantom whose acoustic properties are close to those of tissue was constructed for visualizing therapeutic effects by high intensity focused ultrasound (HIFU). The TM phantom was designed to improve a widely used standard bovine serum albumin (BSA) polyacrylamide hydrogel (PAG), which attenuated ultrasound far less than tissue and, unlike tissue, did not scatter ultrasound. A modified recipe has been proposed in the study by adding scattering glass beads with diameters of 40–80 μm (0.002% w/v) and by raising the concentration of acrylamide (30% v/v). The TM BSA-PAG constructed has an acoustic impedance of 1.67 MRayls, a speed of sound of 1576 m/s, an attenuation coefficient of 0.52 dB/cm at 1 MHz, a backscattering coefficient of 0.242 × 10−3 1/sr/cm at 1 MHz and a nonlinear parameter (B/A) of 5.7. These parameters are close to those of liver. The thermal and optical properties are almost the same as the standard BSA-PAG. The characteristic features of the thermal lesions by HIFU were observed to be more accurately visualized in the TM BSA-PAG than in the standard BSA-PAG. In conclusion, the proposed TM BSA-PAG acoustically mimics tissue better than the standard BSA-PAG and is expected to be preferentially used for assuring if a clinical HIFU device produces the thermal lesion as planned.  相似文献   
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Columellar skin defects may be caused by excision of cutaneous malignancy, trauma, or tissue necrosis associated with surgery. Although columellar skin necrosis rarely occurs following rhinoplasty, this condition might be more common when using an external approach than a closed approach. Columellar skin incision performed with exaggerated tip augmentation may cause columellar necrosis. The nasolabial island flap, used unilaterally to cover columellar skin defects, is used for a single-stage reconstruction procedure and is generally not associated with the need for secondary surgeries. This technique is well suited for repairing columellar skin defects. We experienced a patient with columellar skin necrosis occurring after rhinoplasty which was reconstructed using a unilateral single-stage nasolabial island flap.  相似文献   
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While female mice do not have the equivalent of a menopause, they do undergo reproductive senescence. Thus, to dissociate the effects of aging versus estrogen deficiency on age‐related bone loss, we sham‐operated, ovariectomized, or ovariectomized and estrogen‐replaced female C57/BL6 mice at 6 months of age and followed them to age 18 to 22 months. Lumbar spines and femurs were excised for analysis, and bone marrow hematopoietic lineage negative (lin–) cells (enriched for osteoprogenitor cells) were isolated for gene expression studies. Six‐month‐old intact control mice were euthanized to define baseline parameters. Compared with young mice, aged/sham‐operated mice had a 42% reduction in lumbar spine bone volume/total volume (BV/TV), and maintaining constant estrogen levels over life in ovariectomized/estrogen‐treated mice did not prevent age‐related trabecular bone loss at this site. By contrast, lifelong estrogen treatment of ovariectomized mice completely prevented the age‐related reduction in cortical volumetric bone mineral density (vBMD) and thickness at the tibial diaphysis present in the aged/sham‐operated mice. As compared with cells from young mice, lin– cells from aged/sham‐operated mice expressed significantly higher mRNA levels for osteoblast differentiation and proliferation marker genes. These data thus demonstrate that, in mice, age‐related loss of cortical bone in the appendicular skeleton, but not loss of trabecular bone in the spine, can be prevented by maintaining constant estrogen levels over life. The observed increase in osteoblastic differentiation and proliferation marker gene expression in progenitor bone marrow cells from aged versus young mice may represent a compensatory mechanism in response to ongoing bone loss. © 2010 American Society for Bone and Mineral Research.  相似文献   
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Percutaneous epididymal sperm aspiration (PESA) and intracytoplasmic sperm injection (ICSI) were carried out in patients with congenital bilateral absence of the vas deferens (CBAVD) and men with failed reversal of vasectomy (FRV). PESA was successful in 55 out of 62 patients with CBAVD (89%) and in 57 out of 60 men with FRV (95%). The fertilization rates after ICSI (53 and 55%), cleavage rates (70 and 76%) and pregnancy rates (36 and 32%) did not differ significantly between the two respective groups (CBAVD and FRV). PESA and ICSI are effective both in patients with CBAVD and in those with FRV.   相似文献   
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PROBLEM: To evaluate the efficacy of intracytoplasmic sperm injection (ICSI) treatment in the immunological infertile patients. METHODS: The subjects were 60 cycles of 44 immunological infertile patients and these clinical data were analysed, retrospectively. They were classified into female and male immunological infertility group and were treated with conventional IVF, ICSI, and half-ICSI. RESULTS: The fertilization rate of ICSI (60.3%) and half-ICSI (60.7%) cycles were significantly (P<0.01) higher than conventional IVF (42.6%) cycles. In the male immunological infertility group, fertilization rate was significantly (P<0.01) higher in ICSI (60.7%) and half-ICSI (66.7%) cycles than in conventional IVF (27.4%) cycles and clinical pregnancy rate was higher in ICSI (54.5%) and half ICSI (33.3%) than in conventional IVF (25.0%) cycles. CONCLUSIONS: We suggest that ICSI treatment is highly effective method to improve fertilization and pregnancy rate in IVF-ET program of male immunological infertility.  相似文献   
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Background  

The associations between physical activity, unhealthy dietary habits and cigarette smoking and blood pressure, overweight and obesity are well established in adulthood. This is not the case for similar associations in adolescence. Thus, the purpose of this study is to examine how physical activity, smoking status and dietary habits were related to overweight, obesity and blood pressure in a population of Norwegian adolescents.  相似文献   
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ObjectiveBaseline amyloid burden in mild cognitive impairment (MCI) has been linked to conversion to Alzheimer’s disease (AD), but the comparison of baseline and longitudinal changes in amyloid burden for predicting AD remains unresolved. The objectives of this study aimed to compare the prognostic ability of baseline and longitudinal changes in amyloid burden in MCI patients. MethodsSeventy-five individuals with MCI were recruited and examined annually by clinical interviews for a mean follow-up of 24 months (range, 11.6–42.0). [18F]Florbetaben positron emission tomography (PET) scans were performed. T1-weighted 3D volumes were acquired for co-registration, and to define regions of interest. We examined whether baseline and longitudinal amyloid burden changes can improve AD conversion by Cox proportional hazard model analysis and receiver operating characteristic (ROC) curve analysis. ResultsCox proportional hazards model analysis showed that baseline amyloid burden was significantly associated with increased risk of conversion to AD (hazard ratio [HR]=10.0; 95% confidence interval [CI], 1.15–85.39; p=0.04), but longitudinal amyloid burden changes was not (HR=0.2; 95% CI, 0.02–1.18; p=0.07). When predicting AD, longitudinal amyloid burden changes had better ROC accuracy of 65.2% (95% CI, 48.4–82.0) than baseline amyloid burden of 59.6% (95% CI, 40.3–79.0), without statistical significance in pairwise comparison. ConclusionA single baseline amyloid PET could be sufficient in the prediction of AD conversion in MCI.  相似文献   
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