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1.
· Background: The aim of this study was to evaluate the focal electroretinogram (FERG), an objective indicator of outer retinal function, in nonexudative age-related macular degeneration (NE-AMD), and to compare FERG results with morphological lesions assessed by stereoscopic fundus photographs and fluorescein angiograms. · Methods: Twenty-five patients (25 eyes) with bilateral NE-AMD (visual acuity of the study eyes ≥0.4) as well as 10 age- and sex-matched control subjects (10 eyes) were evaluated. FERGs were recorded from the macular region (9°) in response to sinusoidal stimuli flickered at 32 Hz. Amplitude and phase angle of the Fourier-analyzed FERG fundamental component were measured. Fundus lesions were graded from color slides according to the Wisconsin age-related maculopathy grading system [15]. Fluorescein angiograms were evaluated by an image analysis technique to compute the area with pathological hyperfluorescence (associated with drusen and/or retinal pigment epithelial atrophy) within the macular (approximately 9°×9°) region. · Results: Compared to control eyes, NE-AMD eyes had a reduction in the mean FERG amplitude (57% loss, P<0.001) with no phase changes. Amplitudes of individual affected eyes were negatively correlated with either the Wisconsin grading score (r=–0.63, P<0.001) or the percentage area of pathological hyperfluorescence (r=–0.70, P<0.01). Eyes with minimal NE-AMD lesions (Wisconsin score ≤6) and normal acuity had a lower mean amplitude (47% loss, P<0.05) than that of control eyes. · Conclusions: The results indicate that, in NE-AMD, the FERG is altered in parallel with the extent and severity of fundus lesions. However, a functional impairment of outer macular layers, which is detected by FERG losses, could precede morphological changes typical of more advanced disease. Received: 6 March 1998 Revised version received: 5 June 1998 Accepted: 17 June 1998  相似文献   
2.
Femoral neck fractures in the elderly are frequent, represent a serious health care problem, and have a significant impact on health costs. Reconstruction options using hip arthroplasty include bipolar hemiarthroplasty (HA) and total hip arthroplasty (THA). The purpose of this review is to discuss the indications, limitations, and pitfalls of each of these techniques.  相似文献   
3.
OBJECTIVES: The purpose of this study was to investigate the use of coronary magnetic resonance angiography (MRA) for assessing human epicardial coronary artery vasodilation. BACKGROUND: Coronary vasodilation plays a vital role in the human coronary circulation. Previous studies of epicardial coronary vasodilation have used invasive coronary angiography. Coronary MRA may provide an alternative noninvasive method to directly assess changes in coronary size. METHODS: Thirty-two subjects were studied: 12 patients (age 55 +/- 18 years) and 20 healthy subjects (age 34 +/- 4 years). High-resolution multi-slice spiral coronary MRA (in-plane resolution of 0.52 to 0.75 mm) was performed before and after sublingual nitroglycerin (NTG). Quantitative analysis of coronary vasodilation was performed on cross-sectional images of the right coronary artery (RCA). A time-course analysis of coronary vasodilation was performed in a subset of eight subjects for 30 min after NTG. Signal-to-noise ratio was also measured on the in-plane RCA images. RESULTS: Coronary MRA demonstrated a 23% increase in cross-sectional area after NTG (16.9 +/- 7.8 mm2 to 20.8 +/- 8.9 mm2, p <0.0001), with significant vasodilation between 3 and 15 min after NTG on time-course analysis. The MRA measurements had low interobserver variability (< or =5%) and good correlation with X-ray angiography (r=0.98). The magnitude of vasodilation correlated with baseline cross-sectional area (r=0.52, p=0.03) and age (r=0.40, p=0.019). Post-NTG images also demonstrated a 31% improvement in coronary signal-to-noise ratio (p = 0.002). CONCLUSIONS: Nitroglycerin-enhanced coronary MRA can noninvasively measure coronary artery vasodilation and is a promising noninvasive technique to study coronary vasomotor function.  相似文献   
4.
Purpose  This study was designed to assess the long-term results of stapled hemorrhoidopexy in 291 patients with Grade III and Grade IV hemorrhoids after a minimum follow-up of five years. Methods  Records of patients submitted to stapled hemorrhoidopexy for Grade III and Grade IV hemorrhoids between January 1999 and December 2002 were retrospectively analyzed. Long-term outcome was evaluated with a standardized questionnaire and an office visit, including anorectal examination and rigid proctoscopy. Results  A total of 291 patients with Grade III (57.4 percent) and Grade IV (42.6 percent) hemorrhoids were evaluated. Intraoperative (20.3 percent) and postoperative (4.8 percent) bleeding was the most frequent complication. The questionnaire was submitted to all patients at a median follow-up of 73 (range 60–93) months. There were no symptoms related to hemorrhoids in 65.3 percent of patients, moderate symptoms in 25.4 percent of patients, and severe symptoms in 9.3 percent of patients. Fifty-three (18.2 percent) patients had recurrence. Reoperation was necessary in 21 (7.2 percent) patients (4 in Grade III hemorrhoids and 17 in Grade IV hemorrhoids; P < 0.001), with no recurrent symptoms and/or prolapse. Patient satisfaction for operation was 89.7 percent. Conclusions  Stapled hemorrhoidopexy is a safe and effective treatment for Grade III and Grade IV hemorrhoids. Recurrence requiring reoperation was higher in Grade IV hemorrhoids than in Grade III hemorrhoids. Reprints are not available.  相似文献   
5.

OBJECTIVE:

The purpose of this study was to evaluate the effectiveness of contrast-enhanced ultrasound with a second-generation contrast agent in distinguishing between occlusion and pseudo-occlusion of the cervical internal carotid artery, comparing it with that of conventional Doppler ultrasound and the gold standard, computed tomography angiography.

METHOD:

Between June 2006 and June 2012, we screened 72 symptomatic vascular surgery outpatients at a public hospital. Among those patients, 78 cervical internal carotid arteries were previously classified as occluded by Doppler ultrasound (without contrast). The patients were examined again with Doppler ultrasound, as well as with contrast-enhanced ultrasound and computed tomography angiography. The diagnosis was based on the presence or absence of flow.

RESULTS:

Among the 78 cervical internal carotid arteries identified as occluded by Doppler ultrasound, occlusion was confirmed by computed tomography angiography in only 57 (73.1%), compared with 59 (77.5%) for which occlusion was confirmed by contrast-enhanced ultrasound (p>0.5 vs. computed tomography angiography). Comparing contrast-enhanced ultrasound with Doppler ultrasound, we found that the proportion of cervical internal carotid arteries classified as occluded was 24.4% higher when the latter was used (p<0.001).

CONCLUSIONS:

We conclude that, in making the differential diagnosis between occlusion and pseudo-occlusion of the cervical internal carotid artery, contrast-enhanced ultrasound with a second-generation contrast agent is significantly more effective than conventional Doppler ultrasound and is equally as effective as the gold standard (computed tomography angiography). Our findings suggest that contrast-enhanced ultrasound could replace computed tomography angiography in this regard.  相似文献   
6.
ObjectivesThe aim of this study was to assess the motor profile of children with attention deficit hyperactivity disorder (ADHD), combined type.MethodThe case group consisted of 34 treatment-naive, male patients, aged 7–11 years, who had been diagnosed with ADHD, combined type, without comorbidities (except oppositional defiant disorder). The control group was composed of 32 age- and gender-matched, typically developing children. The evaluation was made using the Motor Development Scale, which assessed global and fine motricity, balance, body scheme, and spatial and temporal organization.ResultsThe results showed that the motor quotients in all areas studied were lower in the ADHD group than in the control group, although in most cases they represent normal values relative to the scale (53% were classified as having “normal medium” motor development, 29% “normal low”, 9% “very low”, 6% “normal high” and 3% as “lower”). Statistically significant differences between groups were observed in general motor age, general motor quotient, balance, spatial organization, and fine and global motricity.ConclusionDifficulties in motor performance were observed in the children with ADHD, combined type. The identification of such deficits may assist in the design of therapeutic protocols for the treatment of children with this type of ADHD.  相似文献   
7.

Background and Objectives:

Routine drainage after laparoscopic cholecystectomy is still controversial. This meta-analysis was performed to assess the role of drains in reducing complications in laparoscopic cholecystectomy.

Methods:

An electronic search of Medline, Science Citation Index Expanded, Scopus, and the Cochrane Library database from January 1990 to June 2013 was performed to identify randomized clinical trials that compare prophylactic drainage with no drainage in laparoscopic cholecystectomy. The odds ratio for qualitative variables and standardized mean difference for continuous variables were calculated.

Results:

Twelve randomized controlled trials were included in the meta-analysis, involving 1939 patients randomized to a drain (960) versus no drain (979). The morbidity rate was lower in the no drain group (odds ratio, 1.97; 95% confidence interval, 1.26 to 3.10; P = .003). The wound infection rate was lower in the no drain group (odds ratio, 2.35; 95% confidence interval, 1.22 to 4.51; P = .01). Abdominal pain 24 hours after surgery was less severe in the no drain group (standardized mean difference, 2.30; 95% confidence interval, 1.27 to 3.34; P < .0001). No significant difference was present with respect to the presence and quantity of subhepatic fluid collection, shoulder tip pain, parenteral ketorolac consumption, nausea, vomiting, and hospital stay.

Conclusion:

This study was unable to prove that drains were useful in reducing complications in laparoscopic cholecystectomy.  相似文献   
8.
9.

Purpose  

The goal of this study was to develop a method to reduce the costs of intraoperative high-field magnet resonance imaging (iMRI). The results of a series of 29 gliomas removed with this technique are presented.  相似文献   
10.
Association of polymyositis with rheumatoid arthritis   总被引:1,自引:0,他引:1  
The association of polymyositis (PM) and rheumatoid arthritis (RA) is described in a 40-year-old female Mexican patient who was studied for a long period of time. The characteristic changes of PM that preceded the onset of RA for 7 years included proximal symmetrical muscle weakness, increased creatine kinase activity, and distinctive electromyography and muscle biopsy results. The occurrence of RA during the final 4 years of the 11-year period was characterized by long-lasting deforming and symmetric polyarthritis, high positive rheumatoid factor, subcutaneous nodules, and erosive joint changes. Through observation, myopathic changes other than those from PM were excluded. Joint changes other than from RA were also ruled out. A review of the literature revealed few specific reports of the coexistence of both diseases.  相似文献   
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