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101.
This investigation evaluated the gastroprotective activity of Astragaloside IV, a cycloartane-type triterpene glycoside isolated from Astragalus zahlbruckneri. Gastric mucosal damage was induced in rats by intragastric ethanol (1 mL/rat). Rats treated orally with Astragaloside IV suspended in Tween 80 at 3, 10 and 30 mg kg(-1), showed 15, 37 and 52% gastroprotection, respectively. The gastroprotection observed at 30 mg kg(-1) for this compound was attenuated in rats pretreated with N(G)-nitro-L arginine methyl ester (70 mg kg(-1), i.p), a nitric oxide (NO)-synthase inhibitor, suggesting that the gastroprotective mechanism of this glycoside involves, at least in part, the participation of NO. The gastroprotective effect of Astragaloside IV was not affected by the inhibition of prostaglandin synthesis with indometacin (10 mg kg(-1), s.c.) nor by the block of endogenous sulfhydryls with N-ethylmaleimide (NEM, 10 mg kg(-1), s.c.). Carbenoxolone was used as a gastroprotective model drug and showed a dose-dependent gastroprotective effect (25, 43 and 88% of gastroprotection, at 3, 10 and 30 mg kg(-1), respectively). The partial participation of prostaglandins, sulfhydryls and NO was observed in the gastroprotective mechanism of carbenoxolone.  相似文献   
102.
Mitomycin C prevents strictures in caustic esophageal burns in rats   总被引:2,自引:0,他引:2  
BACKGROUND: Caustic esophageal injuries lead to stricture formation. Although a number of agents have been tried experimentally to prevent strictures, few have gained clinical application. The purpose of this study was to investigate the effectiveness of Mitomycin C (MMC), which inhibits fibroblastic proliferation in preventing caustic esophageal strictures. MATERIAL AND METHODS: Fifty-six rats were allocated into four groups. Caustic esophageal burns were created as described by Gehanno. Group A was instilled only with saline. Group B was injured and untreated. Groups C and D were injured and received topical MMC at 0.02 and 0.04% concentrations, respectively. At 28 days, stenosis index (SI), collagen deposition, and hydroxyproline content (HP) were determined in distal esophageal segments. Statistical analyses were done. RESULTS: Mean SI in Group B was significantly higher than others (P < 0.05). Mean SI was statistically higher in Group C than A and D and similar between groups A and D. The greatest accumulation of collagen was found in Group B, followed by Group C, D, and A, respectively. Collagen deposition in Group D was statistically lower than Group B (P < 0.01) and similar to Group C. Mean HP in Group B was statistically higher than others (P < 0.05), significantly higher in Group C than Group D (P = 0.047), and similar between Groups A and D (P = 0.73). CONCLUSION: MMC was effective in preventing strictures following experimental caustic esophageal injury, in a dose-dependent manner. We consider that it can gain clinical utilization with the establishment of effective mode, dose, and timing of therapy.  相似文献   
103.
Detrusor underactivity, due to myasthenia gravis (MG) is extremely rare. Only 4 cases of de novo dysfunction have been reported. We report a case of detrusor underactivity and increased post-void residual urine in a woman with MG. The patient has been managed by clean intermittent catheterization 6 times a day.  相似文献   
104.
105.
BACKGROUND: The preventive effect of amrinone on ischaemia/reperfusion (I/R) injury has been shown in the medical literature. The purpose of the present study was to investigate the preventive effect of amrinone on I/R injury of the small bowel of the rat. METHODS: Thirty-two Wistar albino rats (140-180 g) were divided into four groups (n = 8). In all groups except the sham group the superior mesenteric artery was clamped for 30 min. At the beginning of reperfusion, 1 mL of 2405 Bq/mL 51Cr-ethylenediamine tetra-acetic acid (EDTA) was administered into the prepared ileal segment. Following 30 min of reperfusion, 1 mL of blood was obtained from the portal vein. After the rats were killed, the small intestine was removed for histopathological studies. A total of 5 mg/kg amrinone was administered to the rats in group 1 before ischaemia and in group 2 before reperfusion, whereas only saline was administered to the rats in the control group. Statistical analysis was carried out with Kruskal-Wallis and chi2 test, P < 0.01 was considered significant. RESULTS: Both the blood 51Cr-EDTA measurements (mean +/- SD) and mucosal injury grades (MIG) were highest in the control group (3.95 +/- 0.71 c.p.m.; MIG, 3-5) followed by group 2 (0.50 +/- 0.35 c.p.m.; MIG, 1-3), group 1 (0.47 +/- 0.34 c.p.m. MIG, 0-3), and sham group (0.12 +/- 0.05 c.p.m.; MIG, 0). The difference between groups 1 and 2 and the control group were statistically significant (P < 0.01 for each comparison). The results of group 1 and 2 were similar statistically (P > 0.05). CONCLUSIONS: Amrinone was found to be effective in preventing intestinal I/R injury.  相似文献   
106.
107.
Comparison of Prosthetic Materials in Incisional Hernia Repair   总被引:5,自引:0,他引:5  
Purpose Incisional hernias are not uncommon after abdominal surgery, but their repair is associated with a high risk of complications, including adhesions and recurrence. Many different types of meshes and adhesion barriers have been developed in an attempt to overcome these problems, some of which we have assessed in a rat model.Methods We made a full-thickness 1.5 × 2.5-cm abdominal wall defect in 30 Sprague-Dawley rats, which were divided into three groups according to the materials used for repair: 2 × 3-cm polypropylene mesh (group 1); expanded polytetrafluoroethylene (PTFE) with double-layer polypropylene mesh (group 2); or polypropylene mesh with oxidized cellulose adhesion barriers (group 3). We assessed adhesion formation, tensile strength, and histopathologic findings.Results The mean adhesion scores were 3.3, 1.3, and 0.7, in groups 1, 2, and 3, respectively (P < 0.001). The area involved by adhesions was significantly greater in group 1 than in groups 2 or 3 (P < 0.01, P < 0.05), but there was no significant difference between groups 2 and 3 (P < 0.05). The tensile strength in group 2 was less than that in groups 1 or 3 (P < 0.01, P < 0.05), but there was no significant difference between groups 1 and 3 (P > 0.05).Conclusion Although there was less adhesion formation with PTFE and oxidized cellulose, PTFE not only impaired the tensile strength, but also induced fibrosis and inflammation. An oxidized cellulose adhesion barrier can be safely used in incisional hernia repair to prevent intra-abdominal adhesions.  相似文献   
108.
The report describes complete avulsion of knee joint en bloc, from the confines of the soft tissues of the leg but the patient was able to show full range of motion at his ankle and foot with palpable dorsalis paedis and posterior tibial vessels. Arthrodaesis was the best available management option.  相似文献   
109.
Acar F  Naderi S  Guvencer M  Türe U  Arda MN 《Neurosurgery》2005,56(4):861-7; discussion 861-7
A review of the history of ancient medicine reveals that most of the knowledge is concentrated in the studies of a few scientists. The best-known names include Hippocrates, Rufus of Ephesus, Celsus, and Galen. The survival of their works throughout the ages has been the most important factor contributing to their popularity. However, there are other scientists who made great contributions to science, but whose writings have been lost or destroyed over the course of time. As a result, their names are not as well known as those of others and the value of their contributions is not appreciated. With the improvement of communication technology in the past 50 years, links between the studies of ancient science can be made more effectively and scientists who have remained hidden under the shade of time have begun, after thousands of years, to receive the appreciation they deserve. In the field of neuroscience, the historical record focuses on Galen of Pergamon. But, when his marvelous works are carefully studied, it is interesting to note two names he frequently referenced: Herophilus (335-280 BC) and Erasistratus (310-250 BC). These two scientists were the first to place scientific value on the dissection of the human body. Herophilus is considered the father of scientific anatomy, and Erasistratus was the first experimental physiologist. Attracted by the prospect of material advancement and eminent students, both migrated from their homes in Asia Minor to Alexandria. The works of Herophilus and Erasistratus have been lost entirely, but some details of their teachings may be recovered from the writings of Galen. In this study, we focus on Herophilus, a master of ancient medicine, whose important discoveries about the human body formed the basis for positive science and the foundation for neuroscience.  相似文献   
110.
Second branchial anomalies in children   总被引:1,自引:0,他引:1  
AIM: The aim of this study was to evaluate the data of our patients who had been treated for second branchial anomalies in the last 10 years. Here we report our clinical experience in second branchial anomalies with a review of the literature. PATIENTS AND METHODS: We evaluated retrospectively the data of 14 patients, who had been operated on between 1994 and 2004 for second branchial anomalies, in relation to age, sex, complaint at application, diagnostic test, surgical procedures and histopathologic findings. RESULTS: The mean age of the patients (8 female, 6 male) was 5.3 years (range = 1.5-16). The anomalies were usually located on the left side of the neck (n = 6). There were only 3 cases with bilateral anomalies. The majority of the lesions were sinuses (93%). The most frequent clinical feature was the presence of persistent discharge from an external (cutaneous) orifice. All lesions were excised by performing a second step ladder incision. Eight of the lesions were removed under the guidance of 3/0 polypropylene suture. No postoperative complication or recurrence was observed during the follow-up period. CONCLUSIONS: Second branchial arches anomalies are the most common branchial anomalies. Sinuses are more frequently encountered in children. Definitive treatment for these lesions is surgical excision. A polypropylene suture can be inserted into the tract as a guide to prevent incomplete excision.  相似文献   
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