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To investigate the possible contribution of cellular immunity in the development of radiation injury of the central nervous system, Wag/Rij rats were thymectomized at birth and irradiated to the cervical spinal cord at the age of 3 months. At the time of paralysis or at the end of the follow-up period (when rats were 1-year-old) the animals were sacrificed and the mediastinum was examined histologically. In 95% of the neonatally thymectomized animals no thymus was left. These rats showed a firm impairment of the cellular immunity, as they had a 40% reduction of the T-lymphocytes in the spleen, and a 70% reduction of the mixed lymphocyte reaction, compared to age-matched controls. Both single dose and two-fraction irradiation experiments were performed. No modification of the latency time to develop paralysis was observed comparing thymectomized and age-matched controls. The incidence of foreleg paralysis after cervical spine irradiation (single dose or two-fraction) was identically distributed in the follow-up period for both neonatally thymectomized and control Wag/Rij rats. The ED50 value derived in the single dose experiments was 20.3 Gy for the control animals, and 20.9 Gy for thymectomized rats, and in the two fraction experiments 29 Gy for controls and 29.6 Gy for thymectomized rats. None of these differences are significant. It appears that neonatal thymectomy, in spite of its firm suppression of the cellular immunity, has no major influence on the development of radiation myelopathy in rats.  相似文献   
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Atraumetic Restorative Treatment (ART) has been adopted around the world to avoid unnecessary extractions, especially in non-industrialized countries The development of specific glass ionomer cements marketed for the ART technique has contributed to the technical success rate. In this study. Ketac-Molara (3M ESPE. Dental Medzn Germany) was used to restore 150 Class I cavities in 118 Brazilian public school children, aged from 7–12 years. At baseline and at subsequent recalls. CPI probes with a ball-end of 0.5 millimeters (mm) were used to assess loss of restorative material, and photographic color transparencies of restorations were made. After six months. 83 patients returned for follow-up examinations, with 71.8% of their restorations designated as acceptable. After three years. 49 patients with 57 ART-restorations were evaluated, with 21.0% of these restorations graded as acceptable Another 29.8% of their restorations had been replaced by more permanent materials. The main objective of the ART technique is tooth retention; this was achieved for 94.7% of the restored teeth in a high caries risk population who returned for recalls.  相似文献   
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BACKGROUND: Retroperitoneal leiomyosarcomas (RLMS) are a challenging clinical entity. The vast majority of patients are operated on when tumors are advanced. We report herein a case of RLMS, mimicking acute appendiceal disease and treated successfully via laparoscopy. METHODS: A 37-year-old woman, para 1, was admitted to our department for right lower quadrant abdominal pain, fever, and leukocytosis. She had no changes in gastrointestinal and urologic function. A physical examination revealed the presence of abdominal guarding, rebound, and a tender mass in the right lower quadrant. The abdominal ultrasound showed an inhomogeneous ovoid mass (6 cm in diameter) located below the cecum, with no definite margins, and consistent with an appendiceal abscess. The patient was referred for laparoscopy. The procedure was performed with the aid of 3 ports: a 12-mm trocar in the umbilicus (open technique), a 10-mm trocar in the left iliac fossa, and a 5-mm one in the supra-pubic space. On inspection of the abdominal cavity, a retroperitoneal 6-cm mass was immediately found below the cecum and the appendix. Neither intraperitoneal seeding nor suspected lymph nodes were present. After dissection of the parietal peritoneum, the mass appeared to be encapsulated and well demarcated from all surrounding structures. It was eventually dissected and removed via a plastic bag. A standard appendectomy was also performed. The postoperative course was uneventful, and the patient was discharged on the 3rd day. The histology analysis of the resected specimen showed a totally excised G2 leiomyosarcoma. The appendix had no signs of inflammation. Postoperatively, the patient underwent a total-body CT-scan, which had no signs of residual or distant disease. No adjuvant therapy was necessary. At an 18-month follow-up, the patient was doing well and was disease free. CONCLUSION: Surgery represents the main therapeutic option for resectable RLMS. Laparoscopy is a useful diagnostic tool that allows safe resection of incidentally discovered, small and well encapsulated RLMS.  相似文献   
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In this report, the effects of adenosine on the promyelocytic cell line HL-60 and on T-lymphocytic clones are compared. According to previous reports, adenosine induces a dose-dependent inhibition of DNA synthesis in T-lymphocytes. Conversely, adenosine dose-dependently enhances DNA synthesis in HL-60 cells, as documented with [3H]thymidine uptake studies and flow cytometric cell-cycle analysis. Unlike its effect on lymphocytes, the adenosine effect on HL-60 cells does not seem to be mediated by receptor binding, but it appears to be correlated with an intracellular mechanism following active uptake. Despite the different effects exerted by adenosine on lymphocytes and myeloid cells, a purinergic pathway appears to be more generally involved in the regulation of some phases of cell growth.  相似文献   
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Iron deficiency anemia is the most frequent haematological pathology in pregnancy. Serum ferritin levels represent the state of iron deposits. Low levels are a sure sign of iron deficiency. At the University of Turin we studied the variations of serum ferritin levels during physiological pregnancy and the sensitivity of routine blood tests with respect to serum ferritin levels. Routine haematological blood values along with ferritin levels were measured in 115 patients throughout pregnancy. The mean serum ferritin level was 56 ng/ml in the first trimester, 27.2 ng/ml in the second and 11.8 ng/ml in the third. The incidences of anemia per trimester was 6.6%, 4.8% and 49% respectively (p less than 0.05, chi squared). Our results show that it is important to evaluate iron deposits early in pregnancy by measuring serum ferritin levels in order to determine the need for iron therapy.  相似文献   
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