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OBJECTIVE: The purpose of this study was to evaluate the effect of immediate and delayed post space preparation on the sealing ability of a new root canal filling material. STUDY DESIGN: Seventy-two extracted teeth were prepared and obturated with gutta-percha/AH-Plus and Resilon/Epiphany sealer by the lateral compaction technique. The teeth were divided randomly into 4 groups, and the post space was prepared either immediately after filling or after the obturated teeth had been stored in saline at 37 degrees C for a week. Leakage was determined by a fluid-transport device. RESULTS: The results showed that immediate post space preparation of the Resilon/Epiphany-filled group had a mean leakage value of 0.81 microL/h, whereas the delayed preparation had a mean leakage value of 0.75 microL/h. No difference (P > .05) in microleakage was found between gutta-percha/AH-Plus and Resilon/Epiphany-filled groups after immediate preparation. There was significant difference between gutta-percha/AH-Plus and Resilon/Epiphany groups in the delayed post space preparation (P < .05). CONCLUSION: Epiphany/Resilon obturation achieved better sealing than gutta-percha/AH-Plus at the apical end, especially in delayed post space preparation when mechanical techniques were used.  相似文献   
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Rett syndrome is a severe neurodevelopmental disorder that arises from mutations in the X-linked MECP2 gene. It is almost exclusively seen in girls due to the predominant occurrence of the mutations on the paternal X-chromosome, and also the early postnatal lethal effect of the disease causing mutations in hemizygous boys. We identified a boy with features of classic Rett syndrome who is mosaic for the truncating MECP2 mutation R270X. Chromosome analysis showed normal karyotype. These results indicate that a MECP2 mutation associated with Rett syndrome in females could lead to a similar phenotype in males as a result of somatic mosaicism.  相似文献   
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Reperfusion of hearts with a Ca2+-containing medium after a perfusion period in Ca2+-free medium results in irreversible cell damage (calcium paradox). In this investigation we have studied coronary flow and cyclic AMP and cyclic GMP levels after several periods of Ca2+-free perfusion in isolated rat hearts. We also investigated the effects of papaverine (Pap), noradrenaline (NA), acetylcholine (ACh) and absence of inorganic phosphate during Ca2+-free perfusion on coronary flow (CF) and cyclic nucleotide levels. Inability of the heart to recover contractile activity with development of contracture during the reperfusion period was accepted as indicative of the calcium paradox. Ca2+-free perfusion alone and NA and absence of inorganic phosphate during the Ca2+-free perfusion period increased CF, whereas Pap and ACh decreased it. However, only Ca2+-free perfusion and NA elevated cyclic AMP. On the other hand, Pap and ACh increased cyclic GMP (with a transient rise of cyclic AMP in Pap infusion), and absence of inorganic phosphate decreased both cyclic AMP and cyclic GMP. Pap, ACh and absence of phosphate prevented the calcium paradox. Our study suggests that increased cyclic AMP during the Ca2+-free perfusion may contribute, with the other factors, to the occurrence of the calcium paradox.  相似文献   
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Coloboma of the lens is characterized by notching of the equator of the lens. The cause of the condition is faulty development of the zonule. The lens deprived of its normal pull in the defective region is thicker and more spherical as if there were no loss of its substance. We report five cases of lens coloboma and localized zonular defect without any associated systemic anomalies. One case included retinal detachment; another included an iris coloboma; and a third included iris, choroid and optic disk colobomas and retinal detachment with lens coloboma. The remaining two cases were without associated ocular anomalies. The pathogenic mechanisms and relationship of this defect with the differentiation of the tertiary vitreous and development of the zonule is discussed. The defect most likely occurs in the third to fourth months of gestation during differentiation of the tertiary vitreous in response to toxic, inflammatory or genetic factors.  相似文献   
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From November 3, 1975 to November 3, 1990, 874 kidney transplants were performed at our centers. Of these, 675 (77.2%) were from living donors and 199 (22.8%) were from cadaver donors. Five hundred eighty (66.4%) of the living donors were first degree related while 99 (11.3%) were unrelated or second degree related donors, 29 of which were spouses. All donor recipient pairs were ABO-compatible, with the exception of one pair. Donor recipient relations were wife to husband in 25 cases and husband to wife in 4 cases. All were first grafts and started functioning during surgery. In this series, the follow-up for the recipients was 4 to 64 months (mean 33.5 ± 4.5 months). One-year patient survival and graft survival rates were 92.4% and 81.9%, respectively. Two-year patient survival and graft survival rates were 92.4% and 78.2%, respectively. The single ABO-incompatible case is also doing well, 21 months postoperatively. This study demonstrates that the interspouse kidney transplantation may be used when cadaver organ shortage is a problem. While providing the couple with a better quality of life, interspouse kidney transplantation also enables the couple to share the joy of giving and receiving the gift of life from one another.
Resumen En nuestro centro se efectuaron 874 trasplantes renales entre noviembre 3 de 1975 y noviembre 3 de 1990; 675 (77.2%) fueron de donantes vivos y 199 (22.8%) de donantes cadavéricos; 580 (66.4%) de los donantes vivos fueron familiares de primer grado y 99 (11.3%) fueron donantes no relacionados familiarmente o familiares de segundo grado, de los cuales 29 eran cónyuges. Todas las parejas donante-recipiente exhibieron compatibilidad ABO, con excepción de una. La relación donante-recipiente fue esposa a esposo en 25 casos y esposo a esposa en 4 casos. Todos los injertos eran de primera vez y todos comenzaron a funcionar en la mesa de cirugía. El seguimiento osciló entre 4 y 64 meses (33.5 ± 4.5). Las tasas de sobrevida a un año del paciente y del injerto fueron 92.4% y 81.9% respectivamente; las tasas a dos años fueron 92.4% y 78.2% respectivamente. El único caso ABO no compatible también se encuentra bien, a 21 meses en la actualidad. El presente estudio demuestra que el trasplante renal entre esposos puede ser utilizado cuando haya escases de órganos cadavéricos. Al tiempo que permite una mejor calidad de vida, el procedimiento da a la pareja la oportunidad de gozar el hecho de otorgar y de recibir el regalo de la vida entre uno y otro.

Résumé Nous avons effectué 874 transplantations rénales dans nos centres de transplantation entre le 3 Nov, 1975 et le 3 Nov, 1990. Parmi celles-ci, 675 (77.2%) provenaient de donneurs vivants et 199 (22.8%) des reins provenaient de cadavres. Cinq cent quatre vingt des donneurs vivants (66.4%) étaient parents au premier degré alors que 99 (11.3%) étaient parents au 2è degré ou n'étaient pas parents, parmi lesquels 29 étaient des époux. Tous les couples donneur/receveur, sauf un, étaient compatibles dans le système ABO. Le couple donneur/receveur était femme à mari dans 25 cas et mari à femme dans quatre. Il s'agissait dans tous les cas d'une première greffe et qui a commencé à bien fonctionner sur la table d'opération. Dans cette série, le suivi des receveurs allait de 4 à 64 (33.5 ± 4.5) mois. Les taux de survie des malades et des greffes à un an étaient respectivement de 92.4% et 81.9%. Les taux de survie des malades et des greffes à deux ans étaient respectivement de 92.4% et 78.2%. Le seul cas avec incompatabilité ABO va très bien avec un recul de 21 mois. Cette étude montre que la transplantation entre époux est une solution valable en cas de manque de reins. En plus d'améliorer la qualité de survie du receveur et par là même du couple, cette variété de transplantation donne également au couple la possibilité d'avoir la joie de donner et de recevoir un cadeau de vie de leur époux.
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OBJECTIVE: To analyze the cause of changing maternal mortality ratios (MMRs) in a tertiary women's health center in Turkey in the last eight years. MATERIALS AND METHODS: Charts of patients seen between 1998 and 2005 were retrospectively reviewed. Statistical analysis was performed using the Chi-square test. The results were accepted to be significant when the p value was <0.05. RESULTS: During this period, 27 pregnancy-related deaths were identified via hospital death records. The MMR was found to have decreased in rate by approximately 50% from 822.2/100,000 live births in the previous report including the years 1978-1997 to 412.0/100,000 during the last eight years (p < 0.01). Pregnancy-induced hypertension was still the most frequent cause of maternal death. The decrease in MMR was due to the decrease in the ratio of maternal infection (26.4% in 1978-1997 to 7.4% in 1998-2005, p < 0.01). CONCLUSION: Although treatment in the antenatal care and health service has decreased maternal deaths, it was discovered that the MMR has not reached the optimum levels found in developed countries in the last eight years. Also the percentage of direct obstetric deaths (with the exception of those caused by infection) showed no change and was similar to that found in the previous report (1978-1997).  相似文献   
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After stimulation with a Lundh test meal, plasma concentrations of cholecystokinin (CCK) and pancreatic polypeptide (PP) and output of pancreatic enzymes were measured in 33 patients with exocrine pancreatic insufficiency and 26 healthy subjects. Patients with impairment of pancreatic function were subdivided into those with moderate and severe insufficiency. Plasma CCK and PP were measured by radioimmunoassay. Fasting plasma CCK in patients with pancreatic insufficiency (5.8±1.1 pmol/liter) did not differ significantly from controls (4.2±0.6 pmol/liter). After endogenous stimulation with a Lundh meal, plasma CCK increased in both groups without significant differences over 2 hr. Basal and stimulated plasma levels of pancreatic polypeptide (PP) were markedly decreased only in patients with severe pancreatic insufficiency. Our results demonstrate that basal and meal-stimulated CCK levels in patients with pancreatic insufficiency do not differ from controls. Furthermore the extent of functional impairment of the exocrine pancreas did not influence basal and postprandial CCK release.  相似文献   
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