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This study measured episodic memory deficits in individuals with mild cognitive impairment (MCI) as a function of their vascular burden. Vascular burden was determined clinically by computing the number of vascular risk factors and diseases and neuroradiologically by assessing the presence and severity of white matter lesions (WML). Strategic memory processes were measured with free recall and temporal contextual memory tasks requiring self-initiated retrieval. Nonstrategic memory retrieval processes were appraised with a five-choice recognition procedure. Results showed that MCI participants with high vascular burden displayed impairment of strategic memory processes, whereas MCI participants with no vascular burden showed impairment of both strategic and nonstrategic memory processes. A similar pattern was found whether vascular burden was measured using a clinical index of vascular risk profile or whether it was measured neuroradiologically by assessing the extent and severity of subcortical WML. However, the effect of WML on memory differed as function of level of education, used here as a proxy for cognitive reserve. Among participants with MCI, those who had higher education and no WML were the least memory impaired. The study also examined memory as a function of whether patients later progressed to dementia after a three-year follow-up. When examining progressors’ performance, strategic and nonstrategic processes were both impaired in progressors with no concomitant vascular conditions, whereas progressors with a high vascular burden showed less impairment of nonstrategic than strategic processes. Overall, results indicate that the presence of vascular burden in MCI is associated with selective impairment of strategic memory processes.  相似文献   
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Dentinal hypersensitivity is a painful condition that occurs following periodontal treatment. Many treatment alternatives have been considered for this problem, including treatments with laser and dentinal adhesives. This study compared the sealing ability of Nd:YAG laser versus a new resin in scanning electron microscopy (SEM) micrographs. Ten human premolars were sectioned yielding 30 specimens of each premolar, which were randomly divided into three groups. The laser group was irradiated by Nd:YAG laser (1 W, 10 Hz, 60 s), the resin group was treated with the new Seal & Protect resin according to the manufacturer’s instructions, and the third group served as the control group and did not receive any interventions. After preparation and gold coating of the samples, they were photographed by SEM at two magnifications (1500× and 4000×). The number and diameter (μm) of the dentinal tubules were recorded in selected fields, and analysis of variance (ANOVA) and Tukey tests were used to determine significant differences between groups. The ANOVA results revealed significant differences in both the mean number (P < 0.001) and diameter (P < 0.05) among the three groups. Further statistical analysis showed a significant difference between the laser group and the resin group in both outcome measures (P < 0.05). Thus, both Nd:YAG laser and the new resin reduced the number and diameter of open dentinal tubules, a result that also explains the desensitization mechanism of these interventions. We further conclude that application of the new resin is more effective than Nd:YAG laser in minimizing the number and diameter of exposed dentinal tubules.  相似文献   
104.
We describe a case of horseshoe lung in an infant with facio-auriculo-vertebral (FAV) sequence that included mild hemifacial microsomia, ear anomalies, a missing left rib, left hemivertebrae (T2-T4), and complex congenital heart disease. Of the approximately 40 cases of horseshoe lung described since 1962, most are reported in association with scimitar syndrome, and only four reported cases were associated with left lung hypoplasia. None of these cases included malformations consistent with a diagnosis of FAV sequence.  相似文献   
105.
We describe a 41-year-old woman with no cardiac risk factors, typical exertional angina and an abnormal noninvasive stress test. Coronary angiography demonstrated an ambiguous left main coronary artery (LMCA) stenosis. Intravascular ultrasound (IVUS) demonstrated no atheroma, but the minimum lumen diameter and area of the ostial LMCA were significantly reduced. Transesophageal echocardiography showed normal left ventricular function with a bicuspid aortic valve. Two-vessel coronary artery bypass grafting was subsequently performed. To our knowledge, this is the first IVUS-documented case of a congenital left main coronary artery stenosis associated with a bicuspid aortic valve.  相似文献   
106.
Serial liver biopsies are the gold standard by which the progression of fibrosis is evaluated. This longitudinal cohort study assessed the different rates in the progression of fibrosis using serial liver biopsies and serum fibrosis markers YKL-40 and PIIINP and the cytokines, transforming growth factor beta (TGF-beta) and tumor necrosis factor alpha (TNuF-alpha). A 10-year cohort study was performed in patients with hepatitis C virus (HCV) alone or HCV and schistosomiasis. Patients were enrolled at the time of acute HCV infection and prospectively evaluated with two liver biopsies (at entry and end of follow-up), and true rates in the progression of fibrosis were calculated per year. Serum YKL-40, N-terminal propeptide of collagen III (PIIINP), TGF-beta, and TNF-alpha were measured, as well as the expression of TGF-beta, TNF-alpha, and YKL-40 mRNA in liver tissue. A significant increase in the progression rates of fibrosis occurred in the coinfected group (0.61 +/- 0.13) compared with the HCV monoinfection group (0.1 +/- 0.06; P < .001)). The progression of fibrosis rate/year had a direct linear correlation for YKL-40 (r = 0.892, P < .001) and for PIIINP (r = 0.577, P < .01). YKL-40 showed a linear correlation with TGF-beta (r = 0.897, P < .001). Hepatic mRNA levels of YKL-40 and TGF-beta correlated with the serum levels, confirming a hepatic source for the elevated serum levels. In conclusion, serial cytokine and fibrosis markers can accurately determine the rate at which fibrosis is progressing, identifying both those with rapid fibrosis and those with stable disease.  相似文献   
107.
We evaluated histologically 10 biopsy specimens taken preoperatively from the anterior-inferior glenohumeral ligament from patients with atraumatic instability who had undergone radiofrequency capsular shrinkage, 10 taken immediately postoperatively, and 13 taken before revision. The synovial and subsynovial layers returned to normal histology in biopsy specimens taken from 6 months onwards. Collagen bundles in the fibrous layer continued to have a reparative histology during the period of the study (up to 37 months). The type of radiofrequency probe used (monopolar or bipolar) had no effect on the histologic healing process (P > 0.5, chi2 test). A histologic score was introduced, and this was found to have an excellent intraobserver agreement (weighted kappa, 0.840) and a moderate interobserver agreement (weighted kappa, 0.698).  相似文献   
108.
We report a prospective study of 13 consecutive shoulders treated exclusively with radiofrequency capsular shrinkage for voluntary instability. Before surgery, voluntary instability had ceased in all patients with physiotherapy, but involuntary shoulder instability continued. The mean follow-up was 45 months (range, 32-57 months). According to the system of Rowe et al, the results were excellent in 3 shoulders (23.1%), fair in 1 (7.7%), and poor in 9 (69.2%). All 4 shoulders that had previous stabilization surgery had a recurrence of instability. Of the 6 shoulders with fair and poor Rowe ratings that had no previous stabilization surgery, 4 had a repeat capsular shrinkage. Two of these four shoulders had an excellent Rowe rating at final review. Overall, 5 of 9 patients (55.6%) with no previous surgery achieved stability by radiofrequency stabilization. In conclusion, results of radiofrequency capsular shrinkage in voluntary shoulder instability are poor. Results are improved with repeat capsular shrinkage. Radiofrequency capsular shrinkage is not recommended for patients who have had previous stabilization surgery.  相似文献   
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