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Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
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Swartz  JD; Berger  AS; Zwillenberg  S; Popky  GL 《Radiology》1987,163(3):763-765
Erosions of the ossicular chain that occurred as a complication of noncholesteatomatous chronic otitis media were studied with computed tomography (CT) in 55 patients. The incus (particularly the long and lenticular processes) was the ossicle most commonly involved (50 cases). Coronal and axial CT sections were complementary in the diagnosis of these erosions. Fibrous replacement of the incudostapedial articulation was diagnosed in four cases on axial CT scans when an unusually wide joint was present.  相似文献   
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Background contextSurgical intervention is generally indicated in a pediatric high-grade spondylolisthesis to prevent the progression of deformity or neurologic deterioration and improve the quality of life. However, the outcome of the treatment on the health-related quality of life (HRQOL) of patients with high-grade spondylolisthesis remains largely unknown.PurposeTo describe the changes in the HRQOL of patients with pediatric high-grade spondylolisthesis after surgical and nonsurgical managements.Study designObservational case series with a minimal of 2-year follow-up.Patient sampleTwenty-eight pediatric patients with high-grade spondylolisthesis from a single institution filled the inclusion criteria. Twenty-three patients were managed surgically and five were managed nonsurgically.Outcome measuresSelf-report measures: Scoliosis Research Society questionnaires (SRS-22). Neurologic examination, radiographic evaluation of slip grade.MethodsThe SRS-22 questionnaire was collected at the baseline (initial presentation for the nonsurgical group and preoperative visit for the surgical group) and at the last follow-up. Differences between baseline and last follow-up were evaluated in both groups. Correlation between the baseline score of SRS-22 score and improvement in the SRS-22 score was determined in surgical patients.ResultsIn surgical patients, total SRS-22 scores were 3.31±0.50 at the baseline and 4.26±0.50 at the last follow-up. In nonsurgical patients, total SRS-22 scores were 4.12±0.16 at the baseline and 4.14±0.38 at the last follow-up. Therefore, variation in the SRS-22 total score was +0.94±0.77 (p<.001) for surgical patients and +0.02 ± 0.35 (p=.854) for nonsurgical patients. Improvement of the SRS-22 score was correlated with a low baseline value of SRS-22 (R²=0.61; p<.001). There was no neurologic or slip deterioration during the follow-up for patients treated nonsurgically.ConclusionsThe HRQOL improves after a surgical intervention for high-grade spondylolisthesis. Patients with lower baseline HRQOL scores are those who benefit the most from surgery. Close observation is a safe and feasible option in selected patients with a good baseline HRQOL and no neurologic impairment.  相似文献   
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The primate globus pallidus receives massive innervations from GABAergic striatal neurons that co-release the neuropeptide substance P (SP). To expand our knowledge regarding SP interaction at pallidal level, we used single and double antigen retrieval methods to study the cellular and subcellular localization of SP and its high-affinity receptors neurokinin-1 (NK-1R) and neurokinin-3 (NK-3R) in the globus pallidus of the squirrel monkey (Saimiri sciureus). At the light microscopic level, a large number of neurons and fibers located in both the external (GPe) and internal (GPi) segments of the globus pallidus expressed NK-1R or NK-3R immunoreactivity. At the electron microscopic level, both NK-1R and NK-3R were mainly associated with intracellular sites or located at extrasynaptic positions on the plasma membrane. Presynaptic axon terminals forming symmetric and asymmetric synapses occasionally contained NK-1R and NK-3R. Neurokinin receptors were also observed in a proportion of SP-immunoreactive axon terminals, but these terminals preferentially expressed NK-3R. The pattern of distribution of NK-1R and NK-3R in GPe and GPi indicates that SP effects at pallidal level are mediated through postsynaptic receptor as well as presynaptic autoreceptors and heteroreceptors. These morphological data suggest that, either alone or in conjunction with GABA, SP could have a wide range of effects at pallidal level. This neuroactive peptide may influence in a significant manner the integration and treatment of neural information that flows through the basal ganglia.  相似文献   
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Cystatin-related epididymal spermatogenic protein (CRES) or cystatin 8 (Cst8 gene) is a member of the cystatin superfamily of cysteine protease inhibitors. It differs from typical cystatins because it lacks consensus sites for cysteine protease inhibition and exhibits reproductive-specific expression. In the present study, we examined CRES expression within the testes, efferent ducts, and epididymides of normal mice by light microscope immunolocalization. Alterations to these tissues in male mice lacking the Cst8 gene (Cst8(-/-2)) were also characterized by histomorphometry and electron microscopy. In the normal testis, CRES was localized exclusively in mid and late elongating spermatids. In the efferent ducts, CRES was localized to the apical region of the epithelial cells suggestive of localization in the endosomes. In the initial segment of the epididymis, principal cells showed supranuclear and luminal reactions. In the cauda region, CRES was present exclusively as aggregates in the lumen and was detected in clear cells. Compared with wild-type mice (Cst8(+/+)), older (10-12 months) Cst8(-/-) mice had modest but statistically significant reductions in tubular, epithelial, and/or luminal profile areas in the testis and epididymis. By electron microscopy, some Cst8(-/-) tubules in the testis were normal in appearance, but others showed a vacuolated seminiferous epithelium, degenerating germ cells, and alterations to ectoplasmic specializations. In the epididymal lumen, abnormally shaped sperm heads and tails were noted along with immature germ cells. In addition, principal cells contained numerous large irregularly shaped lysosomes suggestive of disrupted lysosomal functions. In both the testis and epididymis, however, these abnormalities were not apparent in younger mice (4 months), only in the older (10-12 months) Cst8(-/-) mice. These findings suggest that the altered testicular and epididymal histology reflects a cumulative effect of the loss of CRES and support a role for CRES in maintaining the normal integrity and function of the testis and epididymis.  相似文献   
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The role of post‐mastectomy radiotherapy for pT3N0 breast cancers remains undefined. The purpose of this study was to report institutional outcomes for women with pT3N0 breast cancers treated with and without post‐mastectomy radiotherapy. We collected data from two large tumor registries on pT3N0 breast cancers diagnosed between 1985 and 2014. Kaplan–Meier estimates were used to analyze freedom from local‐regional recurrence (FFLR), relapse free survival, and overall survival. This analysis identified 93 women with pT3N0 breast cancers. Of these, 53 received post‐mastectomy radiotherapy and 40 did not. Median follow‐up was 6.2 years and 5.3 years in the non‐post‐mastectomy radiotherapy and post‐mastectomy radiotherapy cohorts, respectively. Women not undergoing post‐mastectomy radiotherapy were more likely to be diagnosed in the 1980s and 1990s and were less likely to receive systemic therapies than women receiving post‐mastectomy radiotherapy (p < 0.05). There was a trend toward increased FFLR in the women receiving post‐mastectomy radiotherapy (p = 0.15). FFLR in the post‐mastectomy radiotherapy cohort was 98% at both 5 and 10 years. For women not receiving post‐mastectomy radiotherapy, FFLR was 88% at both 5 and 10 years. Women not receiving post‐mastectomy radiotherapy in our study had an isolated local‐regional failure rate of 12% at 10 years, despite receiving inferior systemic treatment by current standards. Local‐regional control after post‐mastectomy radiotherapy for pT3N0 breast cancers was excellent. Further research is needed to define post‐mastectomy radiotherapy indications for this patient population when receiving chemotherapy and endocrine therapy in line with current guidelines.  相似文献   
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