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41.
Clin. Otolaryngol. 2012, 37 , 376–381 Objectives: To determine the prevalence of radiation‐induced carotid stenosis, in patients who were treated for head and neck malignancies, using colour‐flow duplex scanning. Design: Prospective controlled study at a single medical centre. Participants: We enrolled two groups of patients. The first (radiotherapy group) consisted of patients who received surgical treatment and adjuvant radiotherapy of the neck. The control group consisted of patients with head and neck malignancies who received only surgical treatment. Main outcome measures: All patients were evaluated with carotid artery ecoDoppler imaging 1 week before and 36 months after the surgical procedure. Intima‐media thickness was measured bilaterally at the internal carotid artery and at the bifurcation. Carotid obstruction was classified as low (0–30%), moderate (31–49%) or severe (≥50%). Results: The preoperative stenosis grade did not differ between groups. In 15/25 patients (60%) in the radiotherapy group, mild stenosis evolved to moderate stenosis, while only 6/37 (16%) of the controls did (P = 0.004). Additionally, 9/39 (23%) patients in the radiotherapy group progressed to severe stenosis compared with only 3/54 (6%) controls (P = 0.029). The overall evolution showed that stenosis worsened in 24/32 (62%) patients in the radiotherapy group and 9/54 (17%) patients in the control groups (P < 0.0001). Conclusions: These results highlight the need to study the long‐term incidence of cerebrovascular events in these two different populations (radiation treated and surgically treated) to identify increased cerebrovascular morbidity.  相似文献   
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长鞭红景天化学成分的研究   总被引:10,自引:0,他引:10  
彭江南  葛永潮  李晓晖 《药学学报》1996,31(10):798-800
长鞭红景天化学成分的研究彭江南,葛永潮,李晓晖(军事医学科学院放射医学研究所,北京100850)红景天是滋补强壮药物,目前正引起人们极大的兴趣,现已有一些产品上市。我们曾对数种红景天的化学成分进行过研究[1~4]。长鞭红景天(Rhodiolafast...  相似文献   
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In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction.  相似文献   
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Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with homologies to endopeptidases, on the X-chromosome), are responsible for X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has raised important questions regarding PEX function at the molecular level. The aim of this study was to analyse 99 HYP families for PEX gene mutations, and to correlate predicted changes in the protein structure with Zn2+ metallopeptidase gene function. Primers flanking 22 characterised exons were used to amplify DNA by PCR, and SSCP was then used to screen for mutations. Deletions, insertions, nonsense mutations, stop codons and splice mutations occurred in 83% of families screened for in all 22 exons, and 51% of a separate set of families screened in 17 PEX gene exons. Missense mutations in four regions of the gene were informative regarding function, with one mutation in the Zn2+-binding site predicted to alter substrate enzyme interaction and catalysis. Computer analysis of the remaining mutations predicted changes in secondary structure, N-glycosylation, protein phosphorylation and catalytic site molecular structure. The wide range of mutations that align with regions required for protease activity in NEP suggests that PEX also functions as a protease, and may act by processing factor(s) involved in bone mineral metabolism.   相似文献   
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Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
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Superficial adenopathy is the most frequent clinical manifestation of lymphoma, both at initial workup and later when disease recurs. Data obtained by means of physical examination and ultrasonography (US) of the cervicosupraclavicular, axillary, and inguinal regions were compared for 120 patients, 60 at the time of initial staging and 60 during follow-up for a previously treated lymphoma. Twenty-nine in the second group had recurrent disease, as confirmed with histologic examination. For all 120 patients, US revealed clinically impalpable lesions in an average of 10.8% of cases for the cervicosupraclavicular region, 17.9% for the axillary region, and 4.1% for the inguinal region. Eight of the 29 relapses were not detected at physical examination, and three were demonstrated solely with US. These findings emphasize the value of US exploration of the superficial node-bearing regions in patients with lymphoma, during both initial staging and follow-up.  相似文献   
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