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Purpose

To evaluate the effects of repeated intravitreal injections of bevacizumab (IVB) versus triamcinolone acetonide (IVT) in the treatment of acute branch retinal vein occlusion (BRVO).

Methods

In this randomized clinical trial, 86 eyes with recent-onset (less than 12?weeks) BRVO were included. Participants were randomly assigned to two treatment groups: (1) IVB group (43 eyes), patients who received three monthly injections of 1.25?mg of IVB, and (2) IVT group (43 eyes), patients who received two injections of 2?mg IVT 2?months apart. Patients were examined at 1, 2, 3, 4, and 6?months after enrollment. Main outcome measure was change in best-corrected visual acuity (BCVA) at 6?months. Secondary outcome measures were central macular thickness (CMT) and intraocular pressure (IOP) changes at month 6.

Results

Mean BCVA improved significantly up to 6?months in both groups from 0.68?±?0.25 to 0.31?±?0.21 logMAR (logarithm of minimum angle of resolution) in the IVB group, and from 0.67?±?0.29 to 0.46?±?0.31 logMAR in the IVT group (P?P?=?0.013) and 6 (P?P?=?0.031) at final visit. Dividing the cases into ischemic and non-ischemic types, a significant difference was noted only in the ischemic cases regarding BCVA improvement and CMT reduction in favor of the IVB group. Mean IOP rise was significantly higher in the IVT group at all visits.

Conclusions

Both 3-times-monthly IVB injections and 2-times IVT injections with a 2-month interval could be effective for improving BCVA and CMT in cases with recent-onset BRVO up to 6?months. However, considering the better visual and anatomic outcomes after IVB injections and the potential complications of IVT injections, we would recommend prescheduled repeated IVB injections for such cases. The favorable responses were more pronounced in the ischemic types of BRVO in this trial; nevertheless, this should be confirmed in larger studies.  相似文献   
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The neurotransmitter γ-aminobutyric acid (GABA) is involved in the process of memory. It has been reported that the inhibition of GABAB receptors has beneficial effects on cognition. The aim of this study was to investigate the role of CGP35348 (a GABAB receptor antagonist) on dentate gyrus GABAB receptor inhibition and its effects on learning and memory impairments that had been induced in adult male rats by microinjection of β-amyloid (Aβ). Seventy Wistar male rats were randomly divided into seven groups: control, sham (receiving the Aβ vehicle only), Aβ, Aβ + CGP35348 (1, 10, and 100 μg/μL), and CGP35348 alone (10 μg/μL). Memory impairment was induced by unilateral interventricular microinjection of Aβ (6 μg/6 μL). Rats were cannulated bilaterally in the dentate gyrus, and then, they were treated for 20 consecutive days. Learning and memory were assessed using the novel object recognition and passive avoidance learning tests. The discrimination index and the step-through latency were significantly increased in the Aβ + CGP35348 group in comparison to the Aβ only group (P?<?0.05 and P?<?0.01, respectively). Data showed that the discrimination index was decreased in the Aβ + CGP35348 group in comparison with the control group (P?<?0.05) and sham group (P?<?0.01). Moreover, the step-through latency was significantly decreased in the Aβ + CGP35348 group in comparison to the control and sham groups (P?<?0.01). Data from this study indicated that intra-hippocampal microinjection of the GABAB receptor antagonist counteracts the learning, memory, and cognitive impairments induced by Aβ. It can be concluded that the GABAB receptor antagonist is a possible therapeutic agent against the progression of acute Aβ toxicity-induced memory impairment.  相似文献   
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BACKGROUND/AIM: In developing countries the standard quadruple therapy containing metronidazole results in suboptimal eradication rates of Helicobacter pylori (<75%). In a retrospective study, we undertook to evaluate efficacy and tolerability of a furazolidone-based regimen (omeprazole, furazolidone, bismuth, and tetracycline) in patients who had previously failed the standard metronidazole-based regimen (omeprazole, metronidazole, bismuth, and amoxicillin). METHODS: The records of H. pylori infected patients who were referred to outpatient clinic (from March 1999 to August 1999) and who underwent previous eradication regimens were studied. A total of 320 cases were noted to have received a metronidazole-based quadruple regimen. From these 320 patients, 80 were noted to have failed this regimen based on a urea breath test. These 80 patients were enrolled in the study and given the furazolidone-based regimen. Side effects were assessed at follow-up visits. At least 2 months after the end of each therapy regimen, a (14)C-urea test was performed in each subject to document the cure of the patients. RESULTS: A total of 80 patients (39 males and 41 females) with a mean age of 43.8 +/- (SD) 13.3 years were studied. The H. pylori eradication rate was 90% with the furazolidone-based regimen. The side effects of this regimen were minor. CONCLUSIONS: A furazolidone-based regimen is effective in patients who do not achieve cure of H. pylori infection with the metronidazole-based quadruple therapy. In areas where the metronidazole resistance is high, initial therapy with a furazolidone-based regimen is recommended.  相似文献   
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AIM: To assess the prevalence of clinically significant lesions in patients with minimal bright red bleeding per rectum (BRBPR). METHODS: Consecutive outpatients prospectively underwent colonoscopy at Loghman Hakim Hospital, Tehran. Minimal BRBPR was defined as small amounts of red blood after wiping or in the toilet bowl. Patients with the following alarm signs were excluded: Positive personal history of colorectal neoplasms or inflammatory bowel disease (IBD), positive first degree family history of colorectal neoplasms, history of altered bowel habits, recent significant weight loss, and presence of iron deficiency anemia. Neoplastic polyps, colorectal carcinoma, and IBD were defined as significant lesions. RESULTS: A total of 402 patients (183 female and 219 male, aged 43.6 ± 15.7 years) were studied. Hemorrhoids (54.2%), anal fissures (14.2%) and ul- cerative colitis (14.2%) were the most common lesions and colonoscopy was normal in 8.0%. Significant lesions were found in 121 (30.1%) patients, including 26 patients (6.5%) with adenocarcinoma and 30 (7.5%) with adenomatous polyps. Almost all patients with significant lesions had at least one lesion in the distal colon; an adenocarcinoma and an adenomatous polyp in the proximal colon were found in 2 patients with hemorrhoids. CONCLUSION: Flexible sigmoidoscopy appears to be sufficient for the evaluation of average risk patients with minimal BRBPR. Rigid sigmoidoscopy may be used as an alternative in patients less than 40 years of age in settings where the former is not available. Thechoice of colonoscopy over flexible sigmoidoscopy in patients aged over 50 years should be individualized.  相似文献   
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BACKGROUND: Dissimilarities in management and outcomes exist between upper tract urothelial carcinoma (UTUC) and urothelial carcinoma of the bladder (UCB). OBJECTIVE: The aim of this study was to analyze the stage-specific impact of upper or lower urinary tract tumor location on oncologic outcomes. DESIGN, SETTING, AND PARTICIPANTS: Data were collected from 4335 patients with UCB treated with radical cystectomy (RC) and bilateral pelvic lymphadenectomy (PLND), 877 patients with ureteral UTUC, and 1615 with pelvicalyceal UTUC treated with radical nephroureterectomy (RNU). No patient received preoperative chemotherapy or radiation therapy. INTERVENTIONS: Patients were treated with RC and bilateral PLND or RNU. MEASUREMENTS: Outcomes were assessed according to primary tumor location. RESULTS AND LIMITATIONS: Compared to UTUC patients, UCB patients had more advanced tumor stage and higher grade, and they were more likely to harbor lymphovascular invasion (LVI) and lymph node metastasis (p<0.001). In non-muscle-invasive tumor stages, UCB patients were more likely to experience disease recurrence and mortality compared to renal pelvicalyceal tumor patients (p<0.002) but not ureteral tumors (p>0.05). In pT2 and pT3 tumors, there was no difference in outcomes between the three tumor locations. In pT4 tumors, patients with ureteral and pelvicalyceal tumors were more likely to experience disease recurrence and mortality compared to UCB patients (p<0.004). These stage-specific findings were unchanged after adjustment for the effects of age, gender, tumor grade, LVI, lymph node status, and adjuvant chemotherapy. This study is limited by its retrospective and multicenter nature. CONCLUSIONS: Stage-specific differences in outcomes exist between UCB and UTUC. The differentially worse outcomes by stage between UCB and UTUC patients underline the differences between both cancer entities and the need for individualized stage-specific management for each patient.  相似文献   
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