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1.
V V Joshi A B Cantor G Altshuler E W Larkin J S Neill J J Shuster C T Holbrook F A Hayes R Nitschke M H Duncan 《Cancer》1992,69(8):2197-2211
Histologic sections (minimum of four sections per patient) from 211 patients with neuroblastoma were reviewed. The tumors were resected before therapy, which was standardized according to age and stage. Low mitotic rate (MR) (less than or equal to ten per ten high-power fields) and calcification emerged as the most significant prognostic features after statistical analysis by stepwise log-rank tests (P less than 0.0001 and P = 0.0065, respectively). Histologic Grades 1, 2, and 3 were defined on the basis of the presence of both, any one, or none of these two prognostic features, respectively (Grade 3 had absence of low MR, i.e., these tumors had high MR [greater than ten per ten high-power fields]). Statistically significant differences in survival were observed in the grades after adjusting for age and stage (P less than 0.001). The degree of differentiation, although significant by itself, was no longer significant after adjusting for the grades. Age groups (less than or equal to 1 versus greater than 1 year of age), which also emerged as an independent prognostic feature (P less than 0.001), were linked with the grades to define two risk groups as follows: (1) a low-risk (LR) group consisting of patients in both age groups with Grade 1 tumors and patients 1 year of age or younger with Grade 2 tumors and (2) a high-risk (HR) group consisting of patients older than 1 year of age with Grade 2 tumors and patients in both age groups with Grade 3 tumors. The difference in survival between LR (160 cases) and HR groups (51 cases) was statistically significant (P less than 0.001). Concordance between these LR and HR groups and the Shimada classification was observed in 84% of cases. The new histologic grading system has the following advantages: (1) use of familiar terminology and histologic features in the grading system and (2) relative ease of assessment because the degree of differentiation does not need to be determined. The grading system should be tested on a new data set with an appropriate histologic sample of similar size to confirm these results. 相似文献
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目的 探索LDH实验检测细胞活力的可行性。方法 原代培养骨髓细胞和软骨细胞,用LDH实验测定上述两组细胞的活力,并与镜下活体观察到细胞的生长状况相比较。与目前比较成熟的测定细胞活力的MTS实验的测得的值相比较。结果 LDH实验对上述两组细胞的活力的测定结果与镜下活体观察到的结果相符合。与MTS实验的测得的结果经统计学处理无显著差异。结论 LDH实验可用于细胞活力的直接测定,而对活细胞的生存、繁殖无影响。 相似文献
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Justin Lee Altshuler D. M.D David Jacobs M.B.A. D. M. D. † 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》1992,4(1):12-15
There has been much interest in the in-office fabrication of ceramic posterior restorations using computer-aided design and computer-aided manufacture (CAD-CAM) units. One concern that practitioners have concerning the use of one of these systems is the initial expense of the CAD-CAM unit for the office. This article deals with the financial implications involved when considering the purchase or lease of a CEREC (CAD-CAM) unit. 相似文献
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A comprehensive haplotype analysis of CYP19 and breast cancer risk: the Multiethnic Cohort 总被引:13,自引:0,他引:13
Haiman CA Stram DO Pike MC Kolonel LN Burtt NP Altshuler D Hirschhorn J Henderson BE 《Human molecular genetics》2003,12(20):2679-2692
The CYP19 gene encodes for aromatase (P450arom), a key steroidogenic enzyme that catalyzes the final step of estrogen biosynthesis. Apart from rare mutations in CYP19 which result in severe phenotypes associated with estrogen insufficiency, little is known about whether common variation in CYP19 is associated with risk of hormone-related diseases. In this study, we employed a haplotype-based approach to search for common disease-associated variants in this candidate breast cancer susceptibility gene among African-American, Hawaiian, Japanese, Latina and White women in the Multiethnic Cohort Study (MEC). We utilized 74 densely spaced single-nucleotide polymorphisms (SNPs) (one every approximately 2.6 kb) spanning 189.4 kb of the CYP19 locus to characterize linkage disequilibrium (LD) and haplotype patterns among 69-70 individuals from each ethnic population. We detected four regions of strong LD (blocks 1-4) that were quite closely conserved across populations. Within each block there was a limited diversity of common haplotypes (5 to 10 with a frequency >/=5%) and most haplotypes were observed to be shared across populations. Twenty-five haplotype-tagging SNPs (htSNPs) were selected to predict the common haplotypes with high probability (average Rh2=0.92) and genotyped in a breast cancer case-control study in the MEC (cases, n=1355; controls, n=2580). We first performed global tests for differences in risk according to the common haplotypes and observed significant haplotype-effects in block 2 [P=0.01; haplotypes 2b (OR=1.23; 95% CI, 1.07-1.40), 2d (OR=1.28; 95% CI, 1.01-1.62)]. We also found a common long-range haplotype comprised of block-specific haplotypes 2b and 3c to be associated with increased risk of breast cancer (haplotype 2b-3c: OR=1.31; 95% CI, 1.11-1.54). Our findings suggest the hypothesis that women with the long-range CYP19 haplotype 2b-3c may be carriers of a predisposing breast cancer susceptibility allele. 相似文献
7.
Depression in women with polycystic ovary syndrome: clinical and biochemical correlates 总被引:7,自引:0,他引:7
Rasgon NL Rao RC Hwang S Altshuler LL Elman S Zuckerbrow-Miller J Korenman SG 《Journal of affective disorders》2003,74(3):299-304
BACKGROUND: We assessed the prevalence of mood disturbance among women with prospectively documented polycystic ovary syndrome (PCOS). METHODS: Thirty-two women with PCOS completed the Center for Epidemiological Studies-Depression Rating Scale (CES-D). Clinical and biochemical characteristics were assessed. RESULTS: Sixteen women had CES-D scores indicative of depression. Depression was associated with greater insulin resistance (P=0.02) and higher body mass index (P=0.05). Women receiving oral contraceptives for the treatment of PCOS were less depressed than patients not receiving treatment (P=0.03). LIMITATIONS: Possible selection bias, use of a screening tool alone without further diagnostic evaluation of depression, small samples size and lack of direct comparison with an age matched control group, should be considered in interpretation of these results. CONCLUSION: Findings suggest a high prevalence of depression among women with PCOS, and an association between depression and PCOS markers. 相似文献
8.
Mutations in the Ca(2+)-sensing receptor gene cause autosomal dominant and sporadic hypoparathyroidism 总被引:3,自引:0,他引:3
Baron J; Winer KK; Yanovski JA; Cunningham AW; Laue L; Zimmerman D; Cutler GB Jr 《Human molecular genetics》1996,5(5):601-606
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane
domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that
activating mutations in this receptor might cause autosomal dominant
hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified,
in two families with ADHP, heterozygous missense mutations in the
Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of
50 normal controls had either mutation. We also identified a de novo,
missense Ca(2+)-sensing receptor mutation in a child with severe sporadic
hypoparathyroidism. The amino acid substitution in one ADHP family affected
the N-terminal, extracellular domain of the receptor. The other mutations
involved the transmembrane region. Unlike patients with acquired
hypoparathyroidism, patients with these mutations had hypercalciuria even
at low serum calcium concentrations. Their greater hypercalciuria
presumably reflected activation of Ca(2+)-sensing receptors in kidney
cells, where the receptor negatively regulates calcium reabsorption. This
augmented hypercalciuria increases the risk of renal complications and thus
has implications for the choice of therapy.
相似文献
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