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Summary We prospectively examined bone growth patterns in 894 children aged 6–17 years at the baseline visit, with a 6-year follow-up. Results show bone “tracking” over a six-year interval and sexual dimorphism of bone attained levels and timing of peak bone growth. Our findings underscore childhood and adolescence as critical periods for building bone and developing gender differences. Introduction Bone growth patterns were prospectively examined in 894 Chinese children (496 males), aged 6–17 yrs, from a population-based twin cohort. Whole-body bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were measured by DEXA at baseline and a 6-yr follow-up. Methods Graphic smoothing plots and generalized estimating equations were used to model bone attained levels, growth, and “tracking”. Results Attained levels of BMC and BA increased curvilinearly with age. Male attained levels were higher than females after age ∼15 yr, but BMD was lower between 13–17 yrs (Tanner stage I to IV). In both genders, peak BMC and BMD growth lagged ∼2 yrs behind peak BA growth, which lagged 2 yrs behind peak height growth. Peak bone growth occurred 1–3 yrs later in males. Over the 6-yr follow-up, all bone measurements “tracked”, but “shifting” across ranks also occurred, and baseline tertile ranking influenced bone growth. Females with early menarche had higher attained levels than females with late menarche at age 12–13 yrs. Conclusion Our findings confirm and expand previous studies on peak bone growth conducted in Caucasian cohorts, particularly sexually dimorphic and maturational effects. The significant “tracking” of bone measurements in this 6-yr follow-up study underscores the importance that osteoporosis prevention should begin in childhood and adolescence. Fengxiu Ouyang and Binyan Wang contributed equally to this article. Source(s) of support: This study is supported in part by grant R01 HD049059, R01 HL0864619 and R01 AR045651 from the National Institute of Health and by the Food Allergy Project.  相似文献   
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The activity of stereoisomeric [1,2-bis(3-hydroxyphenyl)ethylenediamine] dichloroplatinum(II)-complexes (1-PtCl2,R,S; 2-PtCl2, R,R/S,S; 3-PtCl2, R,R; 4-PtCl2, S,S) on several tumor models (MDA-MB 231 breast cancer cell line; P 388 leukemia, mouse; L 1210 leukemia, mouse; L 5222 leukemia, rat; Ehrlich ascites tumor, mouse--wildtype; cisplatin-, etoposide-, cyclophosphamide-, and daunomycin-resistant, resp.) is described. For comparison the analogous [1,2-bis(4-hydroxyphenyl)ethylendiamine]dichloroplatinum (II)-complexes (5-PtCl2, R, S; 6-PtCl2, R,R/S,S; 7-PtCl2, R,R; 8-PtCl2, S,S) and cisplatin are used. 1-PtCl2 to 4-PtCl2 (OH in 3,3'-positions) show their maximum antitumor effect at lower doses than 5-PtCl2 to 8-PtCl2 (OH in 4,4'-positions). 2-PtCl2 and 6-PtCl2 (R,R/S,S) are more active than 1-PtCl2 and 5-PtCl2 (R,S). 4-PtCl2 and 8-PtCl2 (S,S) are superior to 3-PtCl2 and 7-PtCl2 (R,R). On the L 5222 leukemia 2-PtCl2 (R,R/S,S), 4-PtCl2 (S,S) and 8-PtCl2 (S,S) markedly surpass cisplatin. Strong effects are produced by 2-PtCl2 to 4-PtCl2 on the Ehrlich ascites tumor (wildtype, cisplatin-, etoposide-, cyclophosphamide-, and daunomycin-resistant, resp.). The combination of 4-PtCl2 with cisplatin results in a weakly synergistic effect.  相似文献   
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Fifteen children with renovascular hypertension as a result of aortic thrombosis were followed for a mean of 26 months (range 5 to 58 months) to determine outcome. As neonates, all patients had hypertension and elevated plasma renin activity. Of 11 patients studied with radionuclide renography and scintigraphy, 10 had abnormal renal blood flow; three had complete absence of unilateral perfusion. On follow-up examination all children were normotensive; five children ages 5 to 24 months required antihypertensive medication. Of 15 children, 14 had normal statural growth; all had normal serum creatinine, plasma renin activity, and calculated glomerular filtration rate values. Patients with complete absence of renal perfusion unilaterally remained functionally anephric; children with less severe perfusion deficits had improved perfusion as shown by radionuclide renography and scintigraphy. We believe that many patients with aortic thrombosis and renovascular hypertension who have had aggressive antihypertensive therapy in the neonatal period will have good renal function and increased perfusion to the affected kidney 2 years later.  相似文献   
5.
The influence of family history on DNA repair synthesis, unscheduledDNA synthesis (UDS), was assessed in volunteers with or withouta family history of cancer. UDS, following treatment of mononuclearleukocytes with N-acetoxy-2-acetylaminofluorene, was measuredas the incorporation of [3H] into DNA in the presence of hydroxyurea.The positive family history group (n=71) had an average of 2.4first-degree relatives with cancer, defined as any major cancer,excluding skin cancer: 31 participants reported that canceroccurred in both their parents. The ‘no family history’comparison group (n=29) had no family history of cancer throughthe second degree. There was a significant reduction in UDSin cells from individuals with family history, compared to thosewith no family history (P>0.002). This relationship was notexplained by factors known to influence UDS, such as age, smokingor hypertension. We conclude that reduced UDS in mononuclearleukocytes is associated with a family history of any majorcancer, and is not confined to a history of cancer of any singleorgan site. This conclusion is further supported by the observationthat individuals (n=13) with parents who had an earlier onsetof cancer (<60 years) also had a significantly lower DNArepair synthesis than those (n=18) whose parents had later diagnosisof cancer (>60 years).  相似文献   
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This article describes plastic surgery patients who sought symmetrical recontouring of the width of the face and skull. The basic demographic and personality characteristics of these facial width deformity (FWD) patients and the surgical procedures performed on them are discussed. Details of the surgical and psychological management of three representative cases are given. Speculative conclusions regarding the general characteristics of the FWD population are offered. Suggestions are proposed for a combined surgical-medical psychotherapeutic collaboration in managing these patients.  相似文献   
7.
Children with monostotic and polyostotic bone dysplasias often exhibit localized bone overgrowth. We investigated the presence of nuclear estrogen and nuclear progesterone receptors by solid-phase radioimmunoassay, immunocytochemistry, and radioligand binding in osteoblast cell cultures derived from the areas of overgrowth of membranous bone, noninvolved membranous bone, and normal membranous bone from children undergoing elective craniotomy. Membranous bone of normal children had demonstrable levels of nuclear estrogen and progesterone receptors identified by radioimmunoassay and immunocytochemical assay. Two- to threefold increased levels of these receptors (p less than 0.001 versus normals) were found in cultures derived from the involved bone of two children with monostotic fibrous dysplasia and in one patient with polyostotic dysplasia (McCune-Albright syndrome). The noninvolved bone in our patients with fibrous dysplasia exhibited nuclear sex steroid hormone receptor levels similar to those in the normal children. Radioligand binding studies demonstrated increased sex steroid hormone receptors in cultures derived from involved osteoblasts. The presence of an increased level of sex steroid hormone receptor was accompanied by increased alkaline phosphatase activity and increased production of osteocalcin in vitro compared to normal or noninvolved bone. The mechanisms by which sex steroid hormone receptor levels are increased in the ostotic dysplasias remain to be established.  相似文献   
8.
In a prospective multicenter study 1115 hip fracture patients were registered in Rotterdam (The Netherlands), Sundsvall and Lund (Sweden). The patients had similar background parameters with a mean age of 78 years, about half of them living alone and just above 80 percent coming from independent living

For cervical fracture, hemiarthroplasty was the predominating treatment in Rotterdam (n 169), whereas osteosynthesis was used in Sundsvall (screws n 135) and Lund (hook-pins n 148). The mean (median) hospitalization time was 32 (20) days in Rotterdam, 16 (12) days in Sundsvall, and 17 (10) days in Lund. Discharge to independent living varied from 53 percent in Lund to 72 percent in Sundsvall. Functional outcome (walking ability and ADL capacity) was at 4 months similar in all groups, but at 2 weeks was lower in Rotterdam. Mortality at 2 weeks / 1 month 14 months was in Rotterdam 4/9/20, in Sundsvall 2/4/13, and in Lund 01311 0 percent.

Trochanteric fractures were treated by screwplate in Rotterdam (n 146) and Lund (n 78), and by Ender nails in Sundsvall (n 11 7). The mean (median) hospitalization time was in Rotterdam 39 (29) days, in Sundsvall 24 (1 5) days and in Lund 19 (11) days. Discharge to independent living varied from 41 percent in Lund to 57 percent in Sundsvall. Functional outcome was similar between the groups. Mortality at 2 weeks / 1 month 14 months was in Rotterdam 2/6/14, in Sundsvall 611 2/19 and in Lund 12/12/18 percent.

Thus, our study has shown that it is possible to perform a prospective multicenter study involving different European countries. The functional out- come after 4 months was very consistent between the centers studied, irrespective of choices made concerning operation method and rehabilitation routines. However, a difference in mortality within these first postoperative months was found, which seems attributable to the operation procedure.  相似文献   
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Zusammenfassung Trotz der H?ufigkeit der Erkrankung liegen nur wenige gesicherte Erkenntnisse über die ?tiologie der chronischen Urtikaria vor. Bei 10 Patienten, bei denen keine anderweitige Ursache für die Erkrankung ermittelt werden konnte, führten wir eine Gastroskopie durch. Bei 8 der 10 Patienten konnte eine Besiedlung der Magenschleimhaut mit Helicobacter pylori gesichert werden. Die Urtikaria heilte innerhalb weniger Tage bei allen Patienten ab, nachdem wir eine Therapie mit Amoxicillin und Omeprazol einleiteten. Eingegangen am 6. Februar 1995 Angenommen am 12. Mai 1995  相似文献   
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