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Background contextFew accurate analyses of clinically useful vertebral anatomy have been conducted, and most have focused on thoracic idiopathic scoliosis.PurposeTo evaluate the different anatomic characteristics in scoliosis by disease type and level.Study designObservational cohort study.Patient sampleForty-eight patients with scoliosis were included in this study.Outcome measuresSubjects underwent computed tomography (CT) of the whole spine.MethodsForty-eight patients with scoliosis were included in this study: 15 adolescent idiopathic, 11 cerebral palsy (CP), 10 muscular dystrophy (MD), and 12 congenital (CG) scoliosis patients with similar demographics. Subjects underwent CT of the whole spine, preoperatively. Eight anatomic parameters were measured in multiplanar reconstructive CT images, and statistical analysis was performed to investigate differences.ResultsIn general, values in the anatomic parameters were similar for the four diseases. Each parameter showed the unique change pattern according to the spinal level regardless of curvature shape, direction, or magnitude. In particular, chord length (CL) in MD and CG scoliosis was lower than in adolescent idiopathic scoliosis (AIS) and CP, and pedicle rib unit length was lower in CG scoliosis than in the other diseases (p<.05). Comparisons of convex and concave anatomies in AIS showed that inner pedicle width (PWI) and outer pedicle width (PWO) were wider for convex side, CL, pedicle width, and transverse pedicle angle were greater for concave side (p<.05), and differences were more significant at apices. However, in CP, PWI and PWO were similar between convex and concaves sides (p>.05). Although PWI and PWO were wider for convex sides and CL and pedicle length were greater for concave sides in MD (p<.05), differences were less significant at apices. Particularly, CG scoliosis showed severely deformed anatomy, with differences of seven parameters at apical vertebrae (p<.05).ConclusionClinical anatomies of vertebrae in scoliosis were found to differ significantly at different levels and in terms of convexity and disease type.  相似文献   
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Acute leukemia, secondary myelodysplasia and paroxysmal nocturnal hemoglobinuria evolving from severe aplastic anemia (AA) following immunosuppressive therapy are well recognized. However, severe AA occurring after complete remission of acute promyelocytic leukemia (APL) has been documented only once in 2009. We report a case of 30-year-old male diagnosed with APL who achieved complete cytogenetic remission with all-trans retinoic acid based induction regimen and developed severe AA few months later during maintenance therapy.  相似文献   
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Recent studies from Europe suggest a continuing increase in thyroid cancer, but it is unclear whether this trend also applies to the United States. The current study examined the long-term trend of thyroid cancer in Connecticut. Our results show that the overall age-adjusted incidence rate of thyroid cancer has been increasing in Connecticut, from 1.30/100,000 in 1935–1939 to 5.78/100,000 in 1990–1992 in females, and from 0.30/100,000 in 1935–1939 to 2.77/100,000 in 1990–1992 in males. The increase mainly comes from papillary carcinoma of the thyroid. The birth cohort analyses indicate that the increase in thyroid cancer occurred among cohorts born between 1915 and 1945, which experienced an increase of 31.4% every 5 years in males and 17.3% in females over the period 1960–1979. For those born since the 1945 cohort, the incidence has been decreasing, at rates of 9.3% and 8.3% every 5 years over the period 1975–1992 in males and females, respectively. Age-period-cohort modeling results also suggest a strong birth cohort effect on the observed time trend in both sexes, which closely follows the introduction of radiation treatment of benign childhood conditions in the head and neck between 1920 and the 1950s in the United States. Our results are consistent with the suggested radiation hypothesis, indicating that radiation treatment of benign childhood conditions in the head and neck is largely responsible for the observed increase of thyroid cancer in Connecticut. © 1996 Wiley-Liss, Inc.  相似文献   
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PEG-rHuMGDF injected daily in normal mice causes a rapid dose-dependent increase in megakaryocytes and platelets. At the same time that platelet numbers are increased, the mean platelet volume (MPV) and platelet distribution width (PDW) can be either decreased, normal, or increased depending on the dose and time after administration. Thus, PEG-rHuMGDF at a low dose causes decreases in MPV and PDW, MGDF at an intermediate dose causes an initial increase followed by a decrease in MPV and PDW, and PEG-rHuMGDF at higher doses causes an increase in MPV and PDW followed by a gradual normalization of these platelet indices. In addition to the expected thrombocytosis after 7 to 10 days of daily injection of high doses of PEG-rHuMGDF, a transient decrease in peripheral red blood cell numbers and hemoglobin is noted accompanied in the bone marrow by megakaryocytic hyperplasia, myeloid hyperplasia, erythroid and lymphoid hypoplasia, and deposition of a fine network of reticulin fibers. Splenomegaly, an increase in splenic megakaryocytes, and extramedullary hematopoiesis accompany the hematologic changes in the peripheral blood and marrow to complete a spectrum of pathologic features similar to those reported in patients with myelofibrosis and megakaryocyte hyperplasia. However, all the PEG-rHuMGDF-initiated hematopathology including the increase in marrow reticulin is completely and rapidly reversible upon the cessation of administration of PEG-rHuMGDF. Thus, transient hyperplastic proliferation of megakaryocytes does not cause irreversible tissue injury. Furthermore, PEG-rHuMGDF completely ameliorates carboplatin-induced thrombocytopenia at a low-dose that does not cause the hematopathology associated with myelofibrosis.  相似文献   
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BACKGROUND AND PURPOSE: Inclusion of oligodendroglial tumors may confound the utility of MR based glioma grading. Our aim was, first, to assess retrospectively whether a histogram-analysis method of MR peifusion images may both grade gliomas and differentiate between low-grade oligodendroglial tumors with or without loss of heterozygosity (LOH) on 1p/19q and, second, to assess retrospectively whether low-grade oligodendroglial subtypes can be identified in a population of patients with high-grade and low-grade astrocytic and oligodendroglial tumors.  相似文献   
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This study examined time trends and age-period-cohort patterns in the incidence of cutaneous malignant melanoma (CMM) by gender and anatomic site in Connecticut (United States) between 1950 and 1989, using data from the population-based Connecticut Tumor Registry. A total of 8,249 invasive CMM incident cases were included. Cases were grouped into melanomas of the head and neck, upper limb, lower limb, and trunk. Between 1950 and 1989, rates increased substantially for all sites. The largest relative increases occurred in melanoma of the upper limb for both males and females; the largest absolute increase occurred for melanoma of the trunk in males; and the smallest increase occurred in head and neck melanoma in females. Recent trends for time periods 1970–89 among birth cohorts 1930–69 indicated that the rate of increase of CMM is slowing substantially among males, but not among females. Nevertheless, continued overall increases in CMM incidence are likely in Connecticut in the 1990s in both genders, with a decrease in the male-female ratio. The age-period-cohort patterns were significantly different between the genders and among anatomic sites, suggesting different trends in carcinogenic exposures (mainly ultraviolet radiation from the sun) or etiologic distinctions between males and females and among the sites.This study was supported by the National Institute of Health grant # CA-62986, and #CA-30931. Dr Dubrow received support from a National Cancer Institute Preventive Oncology Academic Award (K07-CA01463).  相似文献   
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BACKGROUND: The aim of this study was to describe acetaminophen developmental pharmacokinetics in premature neonates through infancy to suggest age-appropriate dosing regimens. METHODS: A population pharmacokinetic analysis of acetaminophen time-concentration profiles in 283 children (124 aged < or = 6 months) reported in six studies was undertaken using nonlinear mixed-effects models. Neonates and infants were given either single or multiple doses of four different formulations: oral elixir, rectal solution, or triglyceride or capsular suppository. The median postnatal age of children younger than 6 months was 1 day (range, birth to 6 months), median postconception age was 40 weeks (range, 28-64 weeks), and median weight was 3.1 kg (range, 1.2-9.0 kg). RESULTS: Population pharmacokinetic parameter estimates and their variability (percent) for a one-compartment model with first-order input, lag time, and first-order elimination were as follows: volume of distribution, 66.6 l (20%); clearance, 12.5 l/h (44%); standardized to a 70-kg person using allometric "1/4 power" models. The volume of distribution decreased exponentially with a maturation half-life of 11.5 weeks from 109.7 l/70 kg at 28 weeks after conception to 72.9 l/70 kg by 60 weeks. Clearance increased from 28 weeks after conception (0.74 l x h(-1) x 70 kg(-1)) with a maturation half-life of 11.3 weeks to reach 10.8 l x h(-1) x 70 kg(-1) by 60 weeks. The absorption half-life for the oral elixir preparation was 0.21 h (120%) with a lag time of 0.42 h (70%), but absorption was further delayed (2 h) in premature neonates in the first few days of life. Absorption half-life parameters for the triglyceride base and capsule suppositories were 0.80 h (100%) and 1.4 h (57%), respectively. The absorption half-life for the rectal solution was 0.33 h. Absorption lag time was negligible by the rectal route for all three formulations. The bioavailability of the capsule suppository relative to elixir decreased with age from 0.92 (22%) at 28 weeks after conception to 0.86 at 2 yr of age, whereas the triglyceride base decreased from 0.86 (35%) at 28 weeks postconception to 0.5 at 2 yr of age. The relative bioavailability of the rectal solution was 0.66. CONCLUSIONS: A mean steady state target concentration greater than 10 mg/l at trough can be achieved by an oral dose of 25 mg x kg(-1) x d(-1) in premature neonates at 30 weeks' postconception, 45 mg x kg(-1) x d(-1) at 34 weeks' gestation, 60 mg x kg(-1) x d(-1) at term, and 90 mg x kg(-1) x d(-1) at 6 months of age. The relative rectal bioavailability is formulation dependent and decreases with age. Similar concentrations can be achieved with maintenance rectal doses of 25 (capsule suppository) or 30 (triglyceride suppository) mg. kg-1. d-1 in premature neonates at 30 weeks' gestation, increasing to 90 (capsule suppository) or 120 (triglyceride suppository) mg x kg(-1) x d(-1) at 6 months. These regimens may cause hepatotoxicity in some individuals if used for longer than 2-3 days.  相似文献   
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