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排序方式: 共有495条查询结果,搜索用时 15 毫秒
1.
乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。 相似文献
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Lindquist R Dupuis G Terrin ML Hoogwerf B Czajkowski S Herd JA Barton FB Tracy MF Hunninghake DB Treat-Jacobson D Shumaker S Zyzanski S Goldenberg I Knatterud GL;POST CABG Biobehavioral Study Investigators 《American heart journal》2003,146(6):1038-1044
Background
Women undergoing coronary artery bypass graft (CABG) surgery have a worse medical condition and fewer social and financial resources than men. Some studies have found that women recover less well than men after CABG, whereas others have found women's outcomes comparable to those of men. Past studies of health-related quality of life after CABG have too few women for adequate comparison with men and have not included patients whose data are not available at baseline (eg, emergency CABG), limiting generalizability.Methods
A longitudinal study of symptoms and health-related quality of life was conducted among patients from four clinical centers enrolling both men (n = 405) and women (n = 269) in the Post CABG Biobehavioral Study in the United States and Canada.Results
After 6 weeks from CABG (average 81 days), both men and women had less anxiety and symptoms related to depression than before surgery (P < .001). After 6 months (average 294 days), both men and women improved in physical and social functioning (P < .001). Although changes in scale scores were similar for men and women at each time point, women scored lower than men on these domains (P < .001, adjusted for baseline medical and sociodemographic differences) and had more symptoms related to depression through 1 year after CABG (P = .003).Conclusions
Both male and female patients improve in physical, social, and emotional functioning after CABG, and recovery over time is similar in men and women. However, women's health-related quality-of-life scale scores remained less favorable than men's through 1 year after surgery. 相似文献4.
Hematopoietic growth factors not only modulate blood progenitor cell activity but also alter the function of mature phagocytes. Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 1 ng/mL for 60 min) did not stimulate luminol-enhanced chemiluminescence of polymorphonuclear leukocytes (PMNs) in suspension but primed PMN for as much as a 15-fold increase in chemiluminescence in response to f-met- leu-phe (fMLP). Mixed mononuclear leukocytes (monocytes [approximately 20%] and lymphocytes [approximately 80%]; MNL) chemiluminescence was very low even after rhGM-CSF priming, but MNLs added to the PMNs (PMN- MNL) resulted in near doubling of rhGM-CSF-primed PMN fMLP-stimulated chemiluminescence. The enhancing factor(s) from MNLs were inherent rather than induced by the GM-CSF, and purified lymphocytes increased GM-CSF-primed PMN chemiluminescence equal to mixed MNLs. We could not detect cell-free "enhancing factor(s)," but cell-to-cell contact further enhanced rhGM-CSF-primed fMLP-stimulated PMN-MNL oxidative activity by 40%. Polyclonal rabbit anti-tumor necrosis factor (TNF) (but not preimmune serum) decreased both fMLP-stimulated rhGM-CSF- primed PMNs and PMN-MNL chemiluminescence, suggesting that TNF on the PMN surface is enhancing GM-CSF-primed chemiluminescence. GM-CSF priming markedly increased PMN superoxide release (sevenfold), but PMN superoxide release was not further enhanced by the presence of MNLs. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) and interleukin-3 (rhIL-3) displayed much smaller effects on pure PMNs and mixed PMN-MNL chemiluminescence and superoxide release than rhGM-CSF. rhGM-CSF primes PMNs for increased oxidative activity more than rhG-CSF and rhIL-3. Maximal oxidative activity was observed when mixed PMN-MNL were primed with GM-CSF in a cell pellet-promoting cell-to-cell contact. This enhanced activity can be attributed, in part, to both inherent enhancing factor(s) on lymphocytes and PMN-associated TNF induced by GM-CSF. 相似文献
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Knatterud GL White C Geller NL Campeau L Forman SA Domanski M Forrester JS Gobel FL Herd JA Hickey A Hoogwerf BJ Hunninghake DB Terrin ML Rosenberg Y 《American heart journal》2003,145(2):262-269
Background Previous studies have suggested that angiographic evidence of disease progression in coronary arteries increases the risk of subsequent coronary clinical events. This study ascertained whether patients enrolled in the Post Coronary Artery Bypass Graft Clinical Trial (POST CABG) who had substantial progression of atherosclerosis in ≥1 saphenous vein grafts (on the basis of assessment of baseline and follow-up angiograms obtained 4-5 years after study entry), but who had not reported clinical symptoms before follow-up angiography, were at a higher risk of subsequent events than patients who did not have substantial progression of atherosclerosis (decrease ≥0.6 mm in lumen diameter at site of greatest change from baseline). Methods All 1351 patients enrolled in the trial underwent baseline angiography; only the 961 patients who had follow-up angiography and no coronary events before the follow-up study were included in this analysis. The clinical center staff contacted patients to ascertain the events that had occurred after follow-up angiography (approximately 3.4 years later). Results Sixty-nine patients had died; 870 patients or relatives were interviewed, and 22 patients could not be contacted. Univariable estimates of relative risk associated with substantial progression ranged from 2.2 (P < .001) for cardiovascular death or nonfatal myocardial infarction to 3.3 (P < .001) for revascularization. Multivariable and univariable estimates of risk were similar. Conclusions The findings provide evidence that patients who had substantial progression of atherosclerosis in vein grafts are at an increased risk for subsequent coronary events and suggest that angiographic changes in vein grafts are appropriate surrogate measures for clinical outcomes. (Am Heart J 2003;145:262-9.) 相似文献
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Primitive hematopoietic stem cells differentiate into committed progenitors that are thought to selectively express hematopoietic growth factor receptor(s), thereby acquiring hematopoietic growth factor responsiveness. To assess whether hematopoietic stem cells express hematopoietic growth factor receptors, the progenitor activity of bone marrow (BM) fractions, isolated by expression of receptors for macrophage/monocyte colony-stimulating factor (M-CSF), were examined. Recovery of day-12 spleen colony-forming units (CFU-S) is diminished in both M-CSF receptor-positive (M-CSFR+) and M-CSFR- fractions, indicating antibody inhibition of day-12 CFU-S. Incubation of BM cells with antibody without fractionation inhibits 50% to 60% of day-12 CFU- S. This inhibition is specific (control antibodies have no effect) and reversible by removal of bound antibody at low pH. Incubating BM cells with control or antireceptor antibody does not affect day-8 CFU-S, which are predominantly erythroid. Treating sublethally irradiated mice with antibody inhibits endogenous day-12 CFU-S. These results indicate that some early progenitors express M-CSFRs, and blocking M-CSFRs inhibits the ability of these progenitors to form colonies, possibly because of inactivation caused by prolonged receptor blockade. 相似文献
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胰岛素样生长因子Ⅰ与肝纤维化 总被引:1,自引:1,他引:1
胰岛素样生长因子I(IGF-I)是体内普遍存在的多肽,循环系统中IGF-I主要来源于肝脏.在垂体生长激素的调控下,IGF-I对多种细胞如成纤维细胞、成骨细胞、平滑肌细胞等的有丝分裂均有调节作用.目前观点认为肝星状细胞(HSC)活化后可分泌大量胶原纤维,是肝纤维化时细胞外基质的主要来源.实验表明 IGF-I能够促进体外培养HSC增殖、活化并抑制其凋亡.而体内研究发现,肝硬化患者血清IGF-I浓度显著下降,外源性小剂量IGF-I 注射能够改善肝功能,为肝纤维化的治疗提供了新的理念. 相似文献
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The color complementation assay (CCA) is a method of allele-specific DNA amplification by which competitive priming and extension of fluorescently labeled oligonucleotide primers determine the color of DNA amplification product. This diagnostic method precludes the need for radioisotopes, electrophoresis, and multiple high-stringency reaction conditions. The multiplicity of mutant globin genes present in Southeast Asians complicates clinical diagnosis and underscores the importance of DNA-based diagnostic methods. We have applied CCA to distinguish beta A and beta E alleles. Competing 15mer primers were a fluorescein-labeled complement to beta A and a rhodamine-labeled complement to beta E, identical except for their central nucleotides. A common unlabeled primer was used to amplify DNA product, the color of which was determined by the perfectly complementary primer. Color photography and spectrofluorometry, as well as a method of black-white photography that we developed to distinguish fluorescein- and rhodamine- labeled DNA, were used to record results. We applied CCA to define the complex genotype of a Thai woman with thalassemia intermedia, 96% HbE, and 4% HbF whose possible genotypes included several permutations of alpha-thalassemia, beta-thalassemia, and beta E genes. zeta-Globin gene mapping of DNA doubly digested with Bg/II and Asp 718 showed the -alpha 3.7/--SEA genotype, and CCA confirmed homozygous beta E/beta E. The CCA is useful for diagnosing the compound hemoglobin genotypes of Southeast Asians and could be applied also to prenatal diagnosis in this population. 相似文献
10.
Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone. 相似文献