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81.
Some 2-[(benzazole-2-yl)thioacetylamino]thiazole derivatives (III) were synthesized by reacting 4-methyl-2-(chloroacetylamino)thiazole derivatives (I) with benzazol-2-thiole (II) in acetone in the presence of K(2)CO(3). The chemical structures of the compounds were elucidated by (1)H NMR and FAB(+)-MS spectral data. The prepared compounds were tested for antimicrobial activity and toxicity.  相似文献   
82.
In this study, a 35% phosphoric acid gel (3M Scotchbond etchant), a nonrinse etchant (NRC), and two EDTA-containing conditioners (RC-Prep and File-Eze) were tested in vitro for blocking nerve conductance evoked in the rat sciatic nerve after local application. The phosphoric acid gel and NRC completely and irreversibly inhibited conductance. On the other hand, RC-Prep reduced the compound action potentials (cAPs) by 50% in 120 min. With File-Eze, the reduction in cAPs was less than 50% after an application time of 160 min (61.8 +/- 1.8%). At 160 min the cAPs in the RC-Prep group had been inhibited by 62.4%. These results indicated strong neurotoxic effects of phosphoric acid and NRC when applied directly on exposed pulp in the total etch procedure.  相似文献   
83.
MURCS association is rare, first described by Duncan in 1979, including nonrandom association of Mullerian duct aplasia or hypoplasia (MU), renal agenesis or ectopy (R), and cervicothoracic somite dysplasia. A 5-year-old girl was admitted to the clinic with a complaint of anteriorly located anus. Physical and radiologic examination of the patient found MURCS association with anorectal malformation (ARM) of rectovestibular-type fistula. She had multiple vertebral anomalies, left renal agenesis, vaginal and uterine agenesia, with a normal female 46,XX karyotype. Posterior sagittal anorectoplasty (PSARP) and sigmoid loop vaginal reconstruction was performed as a one-stage operation for the treatment of vaginal agenesis and ARM. There were no complications in the postoperative period. This combined one-stage operation can be used easily in the treatment of some components of the MURCS association such as vaginal agenesis and ARM as an associated anomaly. J Pediatr Surg 38:262-264.  相似文献   
84.
Ochratoxin A (OTA) is a mycotoxin produced by several fungi. Many foods can be contaminated by OTA, which is consequently found in the blood of humans and animals. It is known that OTA accumulates in the brain. The aim of this study was to investigate the effects of OTA on the brain. For this purpose, the effect of OTA on N-methyl-D-aspartate (NMDA) receptor subunits 2A (NR2A) and 2B (NR2B) in the hippocampus and the protective effect of melatonin were investigated. Three groups of eight rats were used: controls, OTA-treated rats (OTA dose 289 microg/kg per day) and OTA+melatonin-treated rats (melatonin dose 10 mg/kg per day). After four weeks of treatment, electrophoretic examinations were performed using SDS-polyacrylamide gel electrophoresis and Western blotting of hippocampal homogenates of the different groups. The concentrations of NR2A and NR2B in the OTA group were significantly lower than in the control group. The concentration of NR2B was significantly increased when melatonin was co-administered with OTA compared with OTA only. There was also a significant increase in NR2A levels when melatonin was co-administered with OTA. As a result, subchronic administration of OTA reduced hippocampal NMDA receptor subunits 2A and 2B concentrations in rats. It was thought that this alteration might affect cognitive functions because hippocampal NMDA receptors are involved in the memory and learning processes. Melatonin exhibited a partially protective effect on NR2A and NR2B against OTA.  相似文献   
85.
PURPOSE: Many studies have shown that the S-phase fraction is a reflection of the proliferation potential of tumors, and DNA aneuploidy is more common in malignant tumors. In this preliminary study, the authors assessed the Tc-99m MIBI uptake of brain tumors and its relation to tumor grade and DNA content of the tumor cells. METHODS: Ten patients (eight male, two female; mean age, 53.2 +/- 6.11 years) with untreated brain tumors were included in the study. SPECT imaging was performed 20 minutes after injection of 740 MBq (20 mCi) Tc-99m MIBI. A single detector camera with a low-energy high-resolution collimator was used for image acquisition. A region of interest was drawn in the tumor area under magnetic resonance guidance. A Tc-99m MIBI uptake index was computed as the mean tumor-to-background ratio. Flow cytometric analysis of fresh tumor tissue specimens was performed immediately. The percentages of cells in the G0/G1, S, and G2/M phases were determined for each patient. RESULTS: DNA aneuploidy was found in 4 (49%) patients, whereas diploidy was found in 6 (60%) patients. There was a significant positive correlation between the Tc-99m MIBI uptake and the percentage of the S-phase fraction of the cell cycle ( = 0.000, r = 0.95). The Tc-99m MIBI index was significantly greater in aneuploid tumors than in diploid tumors ( < 0.01). CONCLUSIONS: High-grade brain tumors have increased Tc-99m MIBI uptake compared with that of low-grade tumors. Tc-99m MIBI uptake is correlated with the percentage of the S-phase fraction of the cell and the aneuploidy level of the brain tumor. This preliminary report suggests that Tc-99m MIBI imaging may be useful in the evaluation of the biologic characteristics of brain tumors.  相似文献   
86.
BACKGROUND/AIMS: The causes of malnutrition in liver cirrhosis are multifactorial. Levels of IGF-1 (insulin like growth factor-1) that is a crucial regulator of intermediary metabolism decreases. The aim of this study was to analyze the effect of IGF-1 supplementation during liver cirrhosis induced by common bile duct ligation. METHODOLOGY: Rats were divided into five different groups: One sham and four experimental groups. Rats in three of four groups were treated with 2 micrograms/day IGF-1 with a different time of experiment in each group. Blood biochemical parameters, tissue malondialdehyde, glutathione levels and the activity of tissue antioxidant enzymes and conventional and immunohistochemical analysis of liver samples were studied for each group. RESULTS: Serum albumin, total protein, fibrinogen levels decreased and prothrombin time was prolonged in the bile duct ligated and transected experimental group but not in the IGF-I treated rats compared with the rats in sham group. Liver malondialdehyde levels significantly increased in control group but not in IGF-1 treated groups. The activities of antioxidant enzymes were decreased compared with the other groups. Histopathology findings of liver biopsy demonstrated intense degree fibrosis and overexpression of fibroblast growth factor and desmin in the control group but a lesser degree of those in the IGF-1 treated groups. CONCLUSIONS: IGF-1 treatment improves liver function and decreases oxidative liver damage and histopathological findings. Further studies are required to delineate the mechanisms of protective effects of IGF-1.  相似文献   
87.
Deeply seated aggressive fibromatosis also termed as desmoid tumors are rare tumors that invade surrounding structures. Although they never metastasize mortality rate may be as high as 10% due to their aggressive local behavior. Intraabdominal desmoid tumors are usually associated with familial poliposis coli and have a high recurrence rate regardless of the therapy instituted. Sporadic cases are very rare and generous surgical excision may be of benefit. We hereby report 2 siblings with sporadic pancreatic desmoid tumors who also harbor additional fibrotic masses in the pelvis. Although in previously reported cases there is usually a triggering event such as trauma, in the present cases there was no inciting event. Furthermore, the cases are without an associated FAP history, which provides the first clinical clue of a possible genetic determinant in this rare disorder.  相似文献   
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BACKGROUND: We retrospectively reviewed our experience with retrograde ureteroscopy (URS) and a pneumatic lithotriptor in 160 patients with distal ureteral stones to determine whether prior extracorporeal shock wave lithotripsy (ESWL) is a limiting factor in the ureteroscopic procedure. METHODS: From January 1999 to September 2000, we performed URS and pneumatic lithotripsy in 160 patients with distal ureteral stones. Seventy-four patients were treated with URS primarily (Group 1), while the remaining 86 patients received URS only after ESWL had failed (Group 2). For URS and lithotripsy, we used a 9.5 French rigid instrument and vibrolith (Elmed, Ankara, Turkey). RESULTS: In Group 1, 73 of 74 patients (98.6%) were treated successfully by URS alone, as were 81 of 86 patients (94.4%) in Group 2. Impacted stones were also observed in 17 patients from Group 2. In these patients, endoscopic observation revealed edematous inflammation above and below the calculus. Ureteral perforation occurred in one patient from Group 2, which required surgical repair. There was no significant difference in the stone-free rates of the two groups t = 1.4 < 1.96t( infinity,0.05). CONCLUSION: Our data demonstrate that when ESWL fails, URS and pneumatic lithotripsy is as safe and effective as primary URS. Pneumatic lithotripsy also seems to be an effective treatment modality for impacted stones.  相似文献   
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