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131.
Children with Down syndrome have a 150‐fold increased risk of developing acute myeloid leukemia (AML) and 20‐fold increased risk of developing acute lymphoblastic leukemia (ALL). Although the risk of developing AML and ALL is significantly increased in children with Down syndrome, the development of both malignancies in the same patient is very rare. We describe a patient with Down syndrome who developed ALL 6 years after being diagnosed with AML. We performed a literature review and Children's Oncology Group query and discovered eight published cases and five cases of ALL following AML in pediatric patients with Down syndrome, as well as six cases of ALL following AML in non‐Down syndrome patients. There was a similar cumulative incidence of ALL after treatment for AML in the Down syndrome and non‐Down syndrome populations. Overall survival in patients with Down syndrome who developed ALL after treatment for AML was comparable to overall survival for patients with Down syndrome with de novo ALL with an average follow‐up of 7 years after ALL diagnosis. Clinical data collected were used to discuss whether this phenomenon represents a secondary leukemia, second primary cancer, or mixed‐lineage leukemia.  相似文献   
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ObjectivesTo assess and compare the three-dimensional treatment changes in palatal surface area and volume using either tooth-borne (TB) or tooth bone–borne (TBB) rapid maxillary expanders and to evaluate the long-term effects of the two devices and the incidence of the relapse between the groups.Materials and MethodsA total of 52 consecutive patients who met the eligibility criteria were recruited and allocated to either the TB group, mean age 9.3 years (standard deviation [SD], 1.3), or the TBB group, mean age 9.5 years (SD, 1.2). Study casts were taken before, directly after, 1 year after, and 5 years after expansion. Study casts were digitized, superimposed, and evaluated. Participants were randomly allocated in blocks of different sizes using the concealed allocation principle in a 1:1 ratio.ResultsChanges in palatal volume, palatal surface area, and palatal projection area within and between the groups up to 5 years after expansion followed the same pattern and did not show any statistically significant differences between the groups. Relapse was seen in 15% of the patients. It seemed that open-bite and a Class III growth pattern could be assumed as prognosis-deteriorating factors in regard to stability of the treatment.ConclusionsThere were no significant differences between the TB and TBB groups in palatal volume, palatal shell area, or palatal projection area directly after expansion or at 1 year and 5 years after expansion, which implies that the two devices gave rise to the same immediate and long-term outcomes.  相似文献   
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OBJECTIVE: Brain metastasis from uterine cancer is a rare event. Consequently, the optimal management strategy is not defined. We reviewed our institution's experience with brain metastasis from endometrial cancer along with the extant medical literature to develop management recommendations. METHODS: Twenty patients with CNS metastasis were identified. Information regarding symptoms, treatment, and survival was collected. The Kaplan-Meier method was used to compare survival data. RESULTS: The incidence of CNS metastasis was 0.97%. Median patient age at initial diagnosis of endometrial cancer was 62.0 years and 64.0 years at diagnosis of brain metastasis. Most patients initially presented with advanced FIGO stage: 9 stage IVB, 4 stage IIIC, 4 stage IIIA, 2 stage IB, and 1 stage IA. The median interval from diagnosis of endometrial cancer to diagnosis of brain metastasis was 11.5 months (range 0.6-73.6). Median survival after diagnosis of brain metastasis was 2.0 months (range 0.1-39.2). Improved survival was seen in patients treated with multimodal therapy compared to patients who only received whole brain radiotherapy (WBRT) (p=0.0001) or compared to patients who received no treatment (p=0.009). No difference in survival was seen between patients treated with WBRT versus no therapy. The survival advantage associated with multimodal therapy was also supported by case reports and case series in the literature. CONCLUSIONS: Based upon the data presented along with the medical literature, multimodal therapy appears to improve the survival of patients with CNS metastasis from uterine cancer.  相似文献   
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The isoenzymes of lactate dehydrogenase (E. C. 1. 1. 1. 27.) from the periodontal ligament on the root surface of extracted erupted permanent human teeth have been separated and quantitated by means of cellulose acetate membrane electrophoresis.
LDH-3 and LDH-4 were the predominating isoenzymes. and smaller amounts of LDH-2 and LDH-5 were also present. Only traces of LDH-1 could be seen. The results indicate the presence of both aerobic and anaerobic metabolic pathways in the human periodontal ligament.
These pathways bring about an efficient, economical energy production under normal circumstances, and make the survival of this tissue possible under hypoxic conditions, when the blood supply is briefly interrupted. The results further show that determinations of the survival time of the periodontal ligament on a tooth outside its alveolus have to be made by activity measurements of both aerobic and anaerobic enzymes.  相似文献   
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