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OBJECTIVE: Mineral trioxide aggregate (MTA) is being widely used for root-end fillings, pulp capping, perforation repairs, and other endodontic procedures. MTA and Portland cement (PC) have many similar physical, chemical, and biologic properties. PC cement has shown promising potential as an endodontic material in several studies in vitro and in vivo. The purpose of this study was to compare the cytotoxic effect in vitro and the tissue reaction of MTA and Portland cement in bone implantation in the mandibles of guinea pigs. STUDY DESIGN: Millipore culture plate inserts with freshly mixed or set material were placed into the culture plates with already attached L929 cells. After an incubation period of 3 days, the cell morphology and cell counts were studied. Adult male guinea pigs under strict asepsis were anesthetized, during which a submandibular incision was made to expose the symphysis of the mandible. Bilateral bone cavities were prepared and Teflon applicators with freshly mixed materials were inserted into the bone cavities. Each animal received 2 implants, one filled with ProRoot and 1 with PC. The animals were killed after 2 or 12 weeks, and the tissues were processed for histologic evaluation by means of light microscopy. RESULTS: There was no difference in cell reactions in vitro. Bone healing and minimal inflammatory response adjacent to ProRoot and PC implants were observed in both experimental periods, suggesting that both materials are well tolerated. CONCLUSIONS: MTA and PC show comparative biocompatibility when evaluated in vitro and in vivo. The results suggest that PC has the potential to be used as a less expensive root-end filling material.  相似文献   
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This triple-blind placebo-controlled clinical trial was performed to determine the effects of the anti-oxidant vitamin E on blood pressure and heart rate in patients with mild hypertension. A total of 70 new mild hypertensive subjects (systolic blood pressure, SBP: 140-160 mmHg; diastolic blood pressure, DBP: 90-100 mmHg) without secondary hypertension were selected from among people referred to the Hypertension Unit of Isfahan Cardiovascular Research Center and divided randomly into two groups of drug (DG) and placebo (PG). All subjects were aged from 20 to 60 years old, without any other cardiovascular risk factors. The drug group received vitamin E tablets (200 IU/day) and the placebo group received placebo only for 27 weeks. At the beginning and the end of the study, the blood vitamin E level was measured fluorimetrically in all subjects according to the Hansen and Warwick method [14, 15]. Blood pressure and heart rate were measured at the beginning, during, and at the end of the study. Blood pressure was measured by a physician using one random zero mercury sphygmomanometer. Personal information and dietary habits of subjects were collected by separate questionnaire. At the end of the study, it was found that the vitamin E supplement had caused a remarkable decrease in SBP (-24% in DG versus -1.6% in PG) and a less remarkable decrease in DBP (-12.5% in DG versus -6.2% in PG) (p < 0.05). The change in heart rate was -4.3% in DG, and -14.0% in PG (p < 0.05). It is concluded that a vitamin E supplement of 200 IU/day can be effective in mild hypertensive patients in the long term, probably due to nitric oxide, and improve their blood pressure status. Therefore, vitamin E supplement could be recommended to such patients.  相似文献   
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OBJECTIVE: Some genome-wide scans and association studies for schizophrenia susceptibility genes have yielded significant positive findings, but there is disagreement between studies on their locations, and no mutation has yet been found in any gene. Since schizophrenia is a complex disorder, a study with sufficient power to detect a locus with a small or moderate gene effect is necessary. METHOD: In a genome-wide scan of 382 sibling pairs with a diagnosis of schizophrenia or schizoaffective disorder, 396 highly polymorphic markers spaced approximately 10 centimorgans apart throughout the genome were genotyped in all individuals. Multipoint nonparametric linkage analysis was performed to evaluate regions of the genome demonstrating increased allele sharing, as measured by a lod score. RESULTS: Two regions with multipoint maximum lod scores suggesting linkage were found. The highest lod scores occurred on chromosome 10p15-p13 (peak lod score of 3.60 at marker D10S189) and the centromeric region of chromosome 2 (peak lod score of 2.99 at marker D2S139). In addition, a maximum lod score of 2.00 was observed with marker D22S283 on chromosome 22q12, which showed evidence of an imprinting effect, whereby an excess sharing of maternal, but not paternal, alleles was present. No evidence of linkage was obtained at several locations identified in previous studies, including chromosomes 1q, 4p, 5p-q, 6p, 8p, 13q, 15p, and 18p. CONCLUSIONS: The findings of this large genome-wide scan emphasize the weakness and fragility of linkage reports on schizophrenia. No linkage appears to be consistently replicable across large studies. Thus, it has to be questioned whether the genetic contribution to this disorder is detectable by these strategies and the possibility raised that it may be epigenetic, i.e., related to gene expression rather than sequence variation. Nevertheless, the positive findings on chromosome 2, 10, and 22 should be pursued further.  相似文献   
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Definition of malformations of the tragus is important for terminology and treatment. Most common entities are the skin tag, accessory tragus, preauricular sinus, and cyst, whereas macrotragus is an uncommon and unaddressed deformity that should be distinguished from these. In this report, three cases with diagnosis of the macrotragus are presented. The tragus was uniformly large and displaced anteriorly, and external auditory meatus was not obliterated in all cases. For correction, excision of the excess tragal cartilage and skin was performed. In all cases, bilaterally symmetric tragus was achieved. There were no complications in the early postoperative period and there was no enlargement after 6 months of observation. Macrotragus and accessory tragus are different entities that should be distinguished for accurate diagnosis. They have similar histopathological but distinct anatomical characteristics. Although both are treated by a simple excision, in the case of macrotragus, special effort should be taken to leave enough cartilage to restore normal tragal contours. Presented at the 5th Congress of the Balkan Association for Plastic, Reconstructive Aesthetic Surgery, Kuşadası, Turkey, May 22–26, 2007.  相似文献   
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Traumatic brain damage can result in severe visual impairments including hemianopia. Lesions correlated with hemianopia can be located in any part of the retrochiasmatic optic pathway. However, traumatic lesions of the optic tract are relatively rare. We present a case with posttraumatic left homonymous hemianopia who had signal intensity change at the ipsilateral optic tract on MR imaging and ipsilateral occipital hypoperfusion on SPECT imaging.  相似文献   
100.
Intussusception in adults is a rare cause for intestinal obstruction and is usually secondary to some lesion in the gastrointestinal tract GIT. We report a case of intestinal obstruction due to ileo-colic intussusception; an inflammatory fibroid polyp formed the leading edge of the intussusceptum, which is a rare polypoidal lesion of the GIT.  相似文献   
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