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11.
Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
12.
Savitz Dole Williams Thorp McDonald Carter & Eucker 《Paediatric and perinatal epidemiology》1999,13(1):114-125
We describe the study design and patterns of participation for a cohort study of preterm delivery, focused on genital tract infections, nutrition, tobacco use, illicit drugs and psychosocial stress. Women are recruited at 24–29 weeks' gestation from prenatal clinics at a teaching hospital and a county health department. We recruited 57% of the first 1843 eligible women; 29% refused and 8% could not be contacted. White women were somewhat more likely to participate than African-American women (61% vs. 54% respectively). More notable differences were found comparing teaching hospital and health department clinics (71% vs. 47% participation respectively), with the health department clinic having a greater proportion refuse (24% vs. 33%) and more women who could not be contacted (4% vs. 11%). Participation was affected only minimally by day or timing of recruitment, but inability to contact diminished substantially as the study continued (13–0%). Refusals were largely unrelated to patient attributes. Lower education predicted inability to contact. Risk of preterm delivery was 14% among recruited women, 10% among women who refused, and 15% among women whom we were not able to contact, demonstrating that, overall, risk status was not lower among recruited women. 相似文献
13.
Influence of inhaled corticosteroids on growth: a pediatric endocrinologist''s perspective 总被引:7,自引:0,他引:7
DB Allen 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(2):123-129
Given the increasing advocacy for the use of inhaled corticosteroids as a treatment of choice for persistent asthma, growing numbers of children are being exposed to the possible growth-suppressing effects of glucocorticoids. Recent evidence strongly suggests that, when consistently administered at moderate doses, inhaled corticosteroids (IC) are capable of slowing growth in children. Whether such growth suppression would persist and ultimately affect final adult height remains unknown. Therapeutic goals which aim for uninterrupted inflammatory disease control rather than periodic symptom control may increase the occurrence of growth failure in children treated with IC. In this article, current information about the mechanisms of growth suppression by glucocorticoids and the effects of IC on growth is reviewed, and recommendations for designing studies to investigate the effects of drugs on growth are presented. 相似文献
14.
Jasbir S. Johal James W. Thorp Calvin E. Oyer 《Pediatric and developmental pathology》1998,1(5):433-437
We report a neonate with neonatal hemochromatosis (NH), renal tubular dysgenesis (RTD), and hypocalvaria. NH is a fatal condition
of the newborn, characterized by severe idiopathic liver failure of intrauterine onset and siderosis, intra- and extrahepatic,
with sparing of the reticuloendothelial system. RTD is characterized by short, abnormally developed cortical tubules that
lack proximal tubule differentiation. Although both NH and RTD have been reported as entities with a genetic component, similar
findings can be secondary to in utero insults. Hypocalvaria has been reported in association with fetal hypoxia including
that secondary to angiotensin converting enzyme inhibitors. This 38-week-old infant died at 8.5 h. The small nodular liver
weighed 44 g. Grossly, the kidneys were normal. Hypocalvaria was present. Microscopically, the hepatic parenchyma was distorted
by fibrous tracts, proliferation of bile ducts, and abundant iron deposition in hepatocytes. Extrahepatic siderosis in the
pancreas, myocardium, and other organs was consistent with NH. Proximal convoluted tubules were not seen on routine stains
and markers for proximal tubules were negative. Previous reports have linked NH with RTD and RTD with hypocalvaria. This infant
had all three of these rare conditions, which have been hypothesized or shown to be due to genetic factors, hypoxia, or drugs.
The etiology in this case is unknown.
Received May 20, 1997; accepted August 15, 1997. 相似文献
15.
van Kranen HJ; van Iersel PW; Rijnkels JM; Beems DB; Alink GM; van Kreijl CF 《Carcinogenesis》1998,19(9):1597-1601
The variation in colorectal cancer (CRC) incidence worldwide strongly
suggests a role for dietary influences. Based on epidemiological data,
protective effects of vegetables and fruit intake on CRC are widely
claimed, while other data indicate a possible increased CRC risk from
(higher) dietary fat intake. Therefore, we have investigated single and
interactive effects of dietary fat and a vegetable-fruit mixture (VFM) in
the ApcMin mouse, a mouse model for multiple intestinal neoplasia. In this
study, four different diets (A-D) were compared, which were either low in
fat (20% energy diets A/B) or high in fat (40% energy diets C/D). In
addition, 19.5% (wt/wt) of the carbohydrates in diets B and D were replaced
by a freeze-dried VFM. The diets were balanced so that they only differed
among each other in fat/carbohydrate content and the presence of specific
plant-constituents. Because the initiation of intestinal tumors in ApcMin
mice occurs relatively early in life, exposure to the diets was started in
utero. Without the addition of VFM, mice maintained at a high-fat diet did
not develop significantly higher numbers of small or large intestinal
adenomas than mice maintained at a low-fat diet. VFM added to a low-fat
diet significantly lowered multiplicity of small intestinal polyps (from
16.2 to 10.2/mouse, 15 animals/group), but not of colon tumors in male
ApcMin mice only. Strikingly, addition of VFM to female mice maintained on
a low-fat diet and to both sexes maintained on a high-fat diet
significantly enhanced intestinal polyp multiplicity (from 16.5 to 26.7
polyps/mouse). In conclusion, our results indicate that neither a lower fat
intake nor consumption of VFM included in a high-fat diet decreases the
development of polyps in mice genetically predisposed to intestinal tumor
development.
相似文献
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18.
Platelet kinetics in patients with idiopathic thrombocytopenic purpura and moderate thrombocytopenia 总被引:4,自引:2,他引:4
We studied ten normal subjects and 20 patients with stable, untreated idiopathic thrombocytopenic purpura (ITP) and platelet counts in the range of 35,000 to 110,000/microL. The diagnosis was made by clinical criteria. Platelet-associated IgG was increased in all nine of the nine patients studied. Autologous platelets were labeled with chromium 51 and reinfused for measurement of mean cell life and platelet production rate. Mean cell life was calculated by two methods, weighted mean and multiple hit, with excellent agreement between the two. As expected, mean cell life was significantly reduced in ITP patients as compared to the normal subjects (2.9 days v. 8.0 days, P less than .001). However, mean platelet production rates in ITP patients and normal subjects, 3.5 and 3.8 X 10(9) platelets/k/d respectively, were not significantly different. Platelet production rate was above and below the normal range (2 to 5.6 X 10(9) platelets/k/d) in two and four patients, respectively. We conclude that the rate of platelet production is not increased in most patients with ITP who have platelet counts greater than 35,000/microL. We did find that platelet size was increased in eight of the 12 patients in whom it was measured, including two of the patients with low platelet production. 相似文献
19.
Histamine reduces boron neutron capture therapy‐induced mucositis in an oral precancer model
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