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51.
We recorded pattern electroretinograms and visual evoked potentials in a group of selected patients with unilateral uncomplicated branch retinal vein occlusion. To document the effects of preexisting risk factors, patients were divided into three groups: diabetes mellitus, hypertension with hyperlipidemia and no systemic disease. The transient and steady-state pattern electroretinogram and visual evoked potential amplitudes were significantly reduced and visual evoked potential peak times were delayed relative to the fellow eyes and agematched normal subjects. There was a second amplitude reduction relative to the other patient groups in both the affected and fellow eyes of the diabetes mellitus group, which was indicative of an additive effect of diabetes mellitus.Abbreviations BRVO branch retinal vein occlusion  相似文献   
52.
Since it covers the lateral wall of the mastoid air system, the suprameatal triangle is of importance to otologic surgeons during mastoidectomy. Because of this clinical importance, topographic anatomy of the suprameatal spine and depression was studied on Anatolian skulls. In all, 363 male and 231 female skulls were studied. The most prevalent type of suprameatal spine resembled a crest and was found in both sexes on the right (77.6%) and left (80%) sides. The absence of a suprameatal depression was significantly higher in females (right 9.1%; left 8.7%) than in males (right 1.7%; left 2.5%). Suprameatal depressions were mostly shallow in female subjects, but were mostly observed in males to be at a medium depth or deep. Received: 5 January 1998 / Accepted: 19 March 1998  相似文献   
53.
OBJECTIVE: We wanted to compare the efficacies of 95% ethanol and 20% hypertonic saline (HS) sclerotherapies that were performed in a single session under CT guidance for the management of simple renal cysts. MATERIALS AND METHODS: A prospective series of 74 consecutive patients (average age: 57.6 +/- 8.1 years) with simple renal cysts were enrolled in this study. They were randomized into two groups and 95% ethanol or 20% HS, respectively, corresponding to 25% of the aspiration volume, was injected. Treatment success was determined six months later with follow-up clinical evaluation and performing ultrasonography. RESULTS: The sclerotherapy was accepted as technically successful without major complications in all except two patients who were excluded because of a communication between the simple renal cyst and the pelvicalyceal collecting system. Thirty-six patients in the ethanol group received sclerotherapy with 95% ethanol and 36 patients in the HS group underwent sclerotherapy with 20% HS. The complete regression ratio of the ethanol group was significantly higher (94% versus 72%, respectively) than that of the HS group. There was one patient with partial regression in each group. The failure ratio of the ethanol group was significantly lower (3% versus 25%, respectively) than that of the HS group. CONCLUSION: Ethanol sclerotherapy under CT guidance is a successful and safe procedure and it can be used for the treatment of simple renal cysts. Sclerotherapy with 95% ethanol is more effective than 20% HS sclerotherapy. Sclerotherapy with HS may be an option for patients preferring to undergo a less painful treatment procedure.  相似文献   
54.
55.
This study aims to evaluate the effects of gamma-hydroxybutyrate (GHB) after spinal cord trauma (SCT). Twenty rabbits were divided equally into four groups: group I was the sham-operated group, group II suffered from SCT but received no treatment, group III was given a dose of 400 mg/kg of GHB intravenously before SCT and group IV received the same dose after SCT. Cerebrospinal fluid (CSF) samples were obtained 30 min before SCT (T(0)), at 60 (T(1)) and 120 min (T(2)) after SCT. There was a threefold increase in lactate levels from baseline value at T(2) in group II, while statistically significant elevation of the lactate levels were not observed in groups III and IV. Glucose levels at T(1) and T(2) were significantly lower in groups III and IV compared with the control group. The findings of this study demonstrate that GHB can control the increase of CSF lactate and glucose levels following SCT and that this metabolic effect may be associated with neuroprotective physiological changes.  相似文献   
56.
57.
The plantar areas of the foot have specific biomechanical characteristics and play a distinct role in balance and standing. For the forefoot surgeon, knowledge of the variations in the anatomy of communicating branches is important for plantar reconstruction, local injection therapy and an excision of interdigital neuroma. The anatomy of the communicating branches of the plantar nerves between the fourth and third common plantar digital nerves in the foot were studied in 50 adult men cadaveric feet. A communicating branch was present between the third and fourth intermetatarsal spaces nerves in all eight left feet and in six right feet (overall, 28%), and absent in 36 (72%). A communicating branch was found in 14 ft. Ten of the 14 communications were from the lateral to the medial plantar nerve. The length of the communicating branch ranged from 8 to 56 mm (average 16.4 mm) and its diameter was 0.2–0.6 times of the fourth common plantar digital nerve. The angle of the communicating branch with the common plantar digital nerve from which it originated was less than 30° in 11 ft, 30–59° in 27 ft, 60–80° in 8 ft, and more than 80° in 4 ft. Classification of the branch is based on the branching pattern of the communicating branch and explains variations in plantar sensory innervations. We think that the perpendicular coursing communicating branch is at higher risk to be severed during surgery.  相似文献   
58.
Physical training is known to induce oxidative stress in individuals subjected to intense exercise. In this study, we investigated plasma malondialdehyde (MDA) levels and erythrocyte superoxide dismutase (SOD) activity of 25 young male footballers and a control group of similar age. Red blood cell (RBC) count, haemoglobin (Hb) and haematocrit (Hct) values, and copper (Cu) and zinc (Zn) levels were also examined. The maximal oxygen uptake (VO2max) of all subjects was determined in order to establish their functional capacity. The main finding of the present study was that plasma MDA levels, one of the most commonly used markers of lipid peroxidation, of this group of footballers aged under 21 decreased slightly when compared with those of the control group (p < 0.001). In contrast, erythrocyte SOD activity was higher in the footballer group than in the controls (p < 0.001). Footballers who are under regular training showed an improved antioxidant activity in comparison to sedentary controls. Plasma copper concentration, RBC count and Hb concentration of the footballer group were all significantly lower than those of the control group, (p < 0.001, p < 0.01, p < 0.01, respectively). Investigating the footballers' data with Spearman's correlation analyses, the correlation coefficients (r) between Zn/Cu ratio and SOD was positive (r=0.44; p < 0.05); and between VO2max and SOD (r=0.42; p < 0.05) were both positive. On the basis of statistical analysis, we suggest that regular exercise may be beneficial in cases of oxidative damage by reducing the amount of lipid peroxidation and increasing the activity of the antioxidant enzyme SOD.  相似文献   
59.
Self-etching dentin adhesive systems, a new generation of dental-bonding agents, were investigated for their ability to block nerve conductance in the rat sciatic nerve model. Clearfil SE Bond, Mac Bond and FL Bond were used as test materials. Isolated rat sciatic nerves obtained from female albino rats were placed between two electrodes in a bath containing Tyrode solution. The bonding agents were brought into contact with the nerves and the evoked compound action potentials were recorded versus time before and after contact with the materials. Statistical analysis was performed using the Friedman and Wilcoxon Signed-Ranks tests (P = 0.01) to compare the mean percentage of inhibition between test materials versus time. All test materials were able to block nerve transmission rapidly (3.3 +/- 0.5, 5.1 +/- 2.3 and 8.0 +/- 1.9 min for SE Bond, Mac Bond and FL Bond, respectively). Significant differences were found between FL Bond and SE and Mac Bond (P < 0.01). These results indicated that the bonded systems tested, intended primarily as dentinal tubule occluders, may also exert some direct desensitizing effect on intratubular or pulpal nerve terminals in extremely deep cavities or pulpal microexposures, contributing to decreased postoperative pain.  相似文献   
60.
Objective and design: The present study examined effectiveness of low-dose doxycycline (LDD) in combination with nonsurgical therapy on gingival crevicular fluid (GCF) tissue plasminogen activator (t-PA) levels and clinical parameters in chronic periodontitis (CP) a over 12-month period. Methods: GCF samples were collected, probing depth (PD), clinical attachment level (CAL), gingival index (GI) and plaque index were recorded at baseline, 3, 6, 9 and 12 months. CP patients (n = 65) were randomized to LDD or placebo groups. LDD group received LDD (20 mg) b.i.d for 3-months plus and root planing (SRP), while placebo group was given placebo capsules b.i.d for 3-months plus SRP. GCF t-PA levels were determined by ELISA. Friedman, Wilcoxon and Mann-Whitney test was used for statistical analysis. Results: Significant improvement was observed in all clinical parameters in both groups over 12-month period (p < 0.01). LDD group had lower PD, CAL and GI scores than placebo group at 6, 9 and 12-months (p < 0.05). GCF t-PA levels reduced in both groups over 12-month period (p < 0.01). LDD group had lower GCF t-PA levels than placebo group at 6 and 9-months (p < 0.05). Conclusions: These results provide additional information about usefulness of LDD therapy as an adjunct to nonsurgical therapy in long-term management of periodontitis. Received 8 May 2006; returned for revision 13 June 2006; accepted by J. Di Battista 12 July 2006  相似文献   
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