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排序方式: 共有831条查询结果,搜索用时 15 毫秒
61.
Occult malignant breast lesions in 114 patients: relationship to age and the presence of microcalcifications 总被引:2,自引:0,他引:2
Hermann G; Janus C; Schwartz IS; Papatestas A; Hermann DG; Rabinowitz JG 《Radiology》1988,169(2):321-324
This study evaluates the mammographic findings in 352 patients, aged 30-85 years, who underwent spot localization and biopsy for evaluation of nonpalpable breast abnormalities. Malignancy was found at biopsy in 114 cases. The mammographic appearance (specifically, whether grouped microcalcifications, mass, or both were present) was correlated with patient age and histologic findings (specifically, whether the pathologic changes were infiltrating or noninfiltrating in nature). The prevalence of malignant conditions increased directly with age. The presence of grouped microcalcifications as the sole indicator of malignancy was seen in 100% (seven of seven) of the patients in the 30-39-year age group, 64% (18 of 28) in the 40-49-year age group, 37% (11 of 30) in the 50-59-year age group, 30% (seven of 23) in the 60-69-year age group, and 23% (six of 26) in the 70-85-year age group. Of the 49 tumors that were manifested solely as microcalcifications, 34 (69%) were noninfiltrating. The finding of grouped microcalcifications should be aggressively investigated, since it may indicate noninfiltrating carcinoma in an early stage, when the potential for cure is greatest. 相似文献
62.
Does Physical Activity in Adolescence Have Site‐Specific and Sex‐Specific Benefits on Young Adult Bone Size,Content, and Estimated Strength? 下载免费PDF全文
Rachel L Duckham Adam DG Baxter‐Jones James D Johnston Hassanali Vatanparast David Cooper Saija Kontulainen 《Journal of bone and mineral research》2014,29(2):479-486
The long‐term benefits of habitual physical activity during adolescence on adult bone structure and strength are poorly understood. We investigated whether physically active adolescents had greater bone size, density, content, and estimated bone strength in young adulthood when compared to their peers who were inactive during adolescence. Peripheral quantitative computed tomography (pQCT) was used to measure the tibia and radius of 122 (73 females) participants (age mean ± SD, 29.3 ± 2.3 years) of the Saskatchewan Pediatric Bone Mineral Accrual Study (PBMAS). Total bone area (ToA), cortical density (CoD), cortical area (CoA), cortical content (CoC), and estimated bone strength in torsion (SSIp) and muscle area (MuA) were measured at the diaphyses (66% tibia and 65% radius). Total density (ToD), trabecular density (TrD), trabecular content (TrC), and estimated bone strength in compression (BSIc) were measured at the distal ends (4%). Participants were grouped by their adolescent physical activity (PA) levels (inactive, average, and active) based on mean PA Z‐scores obtained from serial questionnaire assessments completed during adolescence. We compared adult bone outcomes across adolescent PA groups in each sex using analysis of covariance followed by post hoc pairwise comparisons with Bonferroni adjustments. When adjusted for adult height, MuA, and PA, adult males who were more physically active than their peers in adolescence had 13% greater adjusted torsional bone strength (SSIp, p < 0.05) and 10% greater adjusted ToA (p < 0.05) at the tibia diaphysis. Females who were more active in adolescence had 10% larger adjusted CoA (p < 0.05), 12% greater adjusted CoC (p < 0.05) at the tibia diaphysis, and 3% greater adjusted TrC (p < 0.05) at the distal tibia when compared to their inactive peers. Benefits to tibia bone size, content, and strength in those who were more active during adolescence seemed to persist into young adulthood, with greater ToA and SSIp in males, and greater CoA, CoC, and TrC in females. © 2014 American Society for Bone and Mineral Research. 相似文献
63.
T. Kaffenberger P. O. Valko J. von Meyenburg K. Baráth E. Hewer F. L. Heppner C. E. Jagella A. Horst M. M. Siccoli 《European journal of neurology》2009,16(2):278-281
Background: Leukoencephalopathy with cerebral calcifications and cysts (LCC) is a recently described, very rare entity, clinically characterized by progressive neurological deficits such as cognitive decline, epileptic seizures, pyramidal, extrapyramidal and cerebellar symptoms/signs. With the exception of two patients with adult onset, in all previously described cases symptoms onset occurred between early infancy and adolescence.
Results: We report a case of late onset LCC in a 59-year-old woman presenting with urinary and fecal incontinence and behavioural changes, then rapid progression with hemianopia, hemiparesis, ataxia and cognitive decline. Extensive work-up was performed, including brain magnetic resonance imaging, magnetic resonance spectroscopy, cyst fluid analysis and brain biopsy, confirming the final diagnosis of LCC.
Conclusion: Our case supports the existence of a late onset adult form of LCC. 相似文献
Results: We report a case of late onset LCC in a 59-year-old woman presenting with urinary and fecal incontinence and behavioural changes, then rapid progression with hemianopia, hemiparesis, ataxia and cognitive decline. Extensive work-up was performed, including brain magnetic resonance imaging, magnetic resonance spectroscopy, cyst fluid analysis and brain biopsy, confirming the final diagnosis of LCC.
Conclusion: Our case supports the existence of a late onset adult form of LCC. 相似文献
64.
65.
Linkage of a familial platelet disorder with a propensity to develop myeloid malignancies to human chromosome 21q22.1-22.2 总被引:2,自引:4,他引:2
Ho CY; Otterud B; Legare RD; Varvil T; Saxena R; DeHart DB; Kohler SE; Aster JC; Dowton SB; Li FP; Leppert M; Gilliland DG 《Blood》1996,87(12):5218-5224
Linkage analysis was performed on a large pedigree with an autosomal dominant platelet disorder and a striking propensity in affected family members to develop hematologic malignancy, predominantly acute myelogenous leukemia. We report the linkage of the autosomal dominant platelet disorder to markers on chromosome 21q22. Four genetic markers completely cosegregate with the trait and yield maximum logarithm of difference scores ranging from 4.9 to 10.5 (theta = .001). Two flanking markers, D21S1265 and D21S167, define a critical region for the disease locus of 15.2 centimorgan. Further analysis of this locus may identify a gene product that affects platelet production and function and contributes to the molecular evolution of hematologic malignancy. 相似文献
66.
Elevation of serum cystathionine levels in patients with cobalamin and folate deficiency 总被引:14,自引:0,他引:14
Homocysteine can be methylated to form methionine by the cobalamin- (Cbl) and folate-dependent enzyme, methionine synthase; serum levels of total homocysteine are elevated in greater than 95% of patients with either Cbl or folate deficiency. Homocysteine can also condense with serine to form cystathionine in a pyridoxal phosphate-dependent reaction catalyzed by cystathionine beta-synthase. Cystathionine is subsequently cleaved to cysteine and alpha-ketobutyrate by the pyridoxal phosphate-dependent enzyme gamma-cystathionase. To assess levels of cystathionine in Cbl and folate deficiency, we developed a new capillary gas chromatographic-mass spectrometric assay and measured cystathionine in the serum of normal subjects and patients with clinically confirmed deficiencies of these vitamins. The normal range for serum cystathionine was 65 to 301 nmol/L (median = 126 nmol/L) for 50 normal blood donors. In 30 patients with clinically confirmed Cbl deficiency, values for cystathionine ranged from 208 nmol/L to 2,920 nmol/L (median = 816 nmol/L) and 26 (87%) had levels above the normal range. In 20 patients with clinically confirmed folate deficiency, cystathionine concentrations ranged from 138 nmol/L to 4,150 nmol/L (median = 1,560 nmol/L) and 19 (95%) had values above the normal range. Five homozygotes for cystathionine beta-synthase deficiency had high values for serum-total homocysteine and low or low-normal values for serum cystathionine that ranged from 30 nmol/L to 114 nmol/L even though they were on treatment with pyridoxine and had partially responded. One patient with a defect in the synthesis of 5-CH3- tetrahydrofolate and five patients with defects in the synthesis of CH3- Cbl had high values for serum-total homocysteine and high values for cystathionine that ranged from 311 nmol/L to 1,500 nmol/L even though they were on treatment with folic acid and Cbl, respectively, and had partially responded. We conclude that levels of cystathionine are evaluated in the serum of most patients with Cbl and folate deficiency and that they are useful in the differential diagnosis of an elevated serum-total homocysteine level. 相似文献
67.
68.
Congenital heart lesions involving the right ventricular outflow tract (RVOT) are a common problem in paediatric cardiology. These patients need multiple surgical interventions in the form of valved conduits over a lifetime. Surgical re-valvulation was the standard treatment option until the introduction of percutaneous pulmonary valves over a decade ago. These valves can be used to prolong the lifespan of conduits and reduce the number of re-operations. The Melody® valve (Medtronic, Minneapolis, MN, USA) was introduced as the first dedicated percutaneous pulmonary valve. Percutaneous pulmonary valves can be implanted successfully and have the advantage of short hospitalisations. We describe the first three Melody® valve implantations in Africa. 相似文献
69.
Bert Hildebrandt Hanno Riess Moritz von Winterfeld Barbara Ingold‐Heppner Wilfried Roth Matthias Kloor Peter Schirmacher Manfred Dietel Sha Tao Lina Jansen Jenny Chang‐Claude Alexis Ulrich Hermann Brenner Michael Hoffmeister 《International journal of cancer. Journal international du cancer》2015,136(8):1957-1966
Colorectal cancer guidelines recommend adjuvant chemotherapy in stage II disease when less than 12 lymph nodes are assessed. The recommendation bases on previous studies showing an association of a low lymph node count and adverse outcome. Compared to current standards, however, the quality of lymph node examination in the studies was low. We, therefore, investigated the prognostic role of <12 lymph nodes in cancers diagnosed adherent to current quality measures. Stage I–IV colorectal cancers from 1,899 patients enrolled into a population‐based cohort study were investigated for the prognostic impact of a lymph node count <12. The stage specific share of patients diagnosed with ≥12 nodes (stage I–IV: 62, 85, 85, 78%, respectively) was used to compare lymph node examination quality to other studies. We found no impact of a lymph node count <12 on overall, cancer‐specific or recurrence‐free survival for any tumour stage. Compared to studies reporting an adverse prognostic impact of a low lymph node count in stages II and III the stage‐specific shares of patients with ≥12 nodes were markedly higher in this study (85% vs. 24–58% in previous analyses) and this correlated with increased rates of stage III compared to stage II cancers. In conclusion our data indicate, that the previously reported effect of a low lymph node count on the patients' outcomes is eliminated by improved lymph node examination quality and thus question the general applicability of a 12 lymph node cut off for adjuvant chemotherapy decision making in stage II disease. 相似文献
70.
Stromal cell-associated erythropoiesis 总被引:5,自引:0,他引:5
A novel cover slip-transfer culture system was designed to study the functional roles of stromal cells in hemopoiesis, particularly erythropoiesis. Human bone marrow stromal cell colonies were allowed to develop on small glass cover slips in liquid medium. The cover slips, along with the stromal cell colonies and progenitors attached to them were then transferred to a new tissue culture dish and overlaid with methylcellulose culture medium. No exogenous colony-stimulating factors except erythropoietin were supplied. Large erythroid bursts, comprising multiple subcolonies, developed on the stromal cells. In order to determine if stromal fibroblasts together with erythropoietin and serum proteins could support erythroid development, human bone marrow cells depleted of monocytes, macrophages, and T lymphocytes were allowed to adhere to monolayers of a homogeneous fibroblastoid human stromal cell strain ST-1 grown on cover slips. The cover slips were then washed to remove nonadherent cells, transferred to a new culture dish, and overlaid with methylcellulose culture medium containing fetal calf serum and erythropoietin. In this modified system as well, primitive erythroid progenitors migrated extensively on and within the stroma to form huge colonies of hemoglobinized erythroblasts that proceeded to enucleate. Our results indicate that (1) ST-1 cells together with serum proteins and erythropoietin can support the development of large erythroid bursts; (2) erythroid progenitors and precursors adhere to and migrate on and within the extracellular matrix elaborated by ST-1 cells; (3) erythroid progenitors are more adherent to the ST-1 cells or the extracellular matrix than are the more mature cells and possibly the myeloid progenitors. 相似文献