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81.
Berger AC Watson JC Ross EA Zalatoris A Hoffman JP 《The American surgeon》2004,70(2):169-73; discussion 173-4
Increased expression of vascular endothelial growth factor (VEGF) by pancreatic cancer correlates with poor survival. The significance of VEGF in biliary and pancreatic secretions in periampullary cancers is unknown. Bile and pancreatic juice samples were collected from patients undergoing pancreaticoduodenectomy (PD). All samples were frozen at -70 degrees C until subsequent analysis for VEGF concentration using enzyme-linked immunoabsorbent assay (ELISA). Plasma VEGF levels in pancreatic cancer patients were <10 pg/mL. The biliary VEGF concentration for patients with malignancy was significantly elevated compared to benign disease (P = 0.05). There was no difference in pancreatic VEGF concentrations between benign and malignant disease. Cancer patients undergoing preoperative chemoradiation (CRT) had lower biliary and pancreatic VEGF concentrations than those who did not. Preoperative biliary drainage (BD) was associated with decreased VEGF concentrations in bile (3500 pg/mL vs 7740 pg/mL, P = 0.027). Patients undergoing both CRT and BD had diminished biliary and pancreatic VEGF concentrations compared to those who had neither. This was statistically significant for pancreatic VEGF concentrations (917 pg/mL vs 4723 pg/mL, P = 0.044). VEGF is highly concentrated in bile and pancreatic juice compared to plasma. Preoperative CRT and BD significantly reduce these levels in patients with periampullary cancers. Antiangiogenic therapy aimed at interrupting the VEGF pathway appears to be a logical target in periampullary cancer. 相似文献
82.
Borges A Borges M Fernandes J Nascimento H Sameiro-Faria M Miranda V Reis F Belo L Costa E Santos-Silva A 《Renal failure》2011,33(2):138-143
End-stage renal disease (ESRD) under hemodialyses (HD) is related with a higher propensity to infections, essentially due to T-cell lymphopenia. We postulated that HD procedure affects CD4(+) T cells, especially by inducing apoptotic death and that recombinant human erythropoietin (rhEPO) therapy may also play an important role in the modulation of the immune system in these patients. T-cell phenotype and apoptosis of HD patients and healthy controls were evaluated by flow cytometry using anticoagulated whole-blood samples. In 12 HD patients, these parameters were also analyzed before and immediately after HD procedure. HD patients showed a decrease in total circulating CD3(+) lymphocytes, especially in CD4(+) T cells (0.747 ± 0.410 vs. 0.941 ± 0.216 × 10(9)/L, p < 0.05), which could be a consequence of the higher proportion of CD3(+) and CD4(+) lymphocytes in the latest stage of apoptosis (or death) and of the higher proportion of apoptotic CD4(+) T cells observed in the patients immediately after HD procedure (2.91 ± 0.780 vs. 3.90 ± 1.96, p < 0.05). A positive and statistically significant correlation between CD3(+) and CD4(+) lymphocytes in latest stage of apoptosis (or death) with HD time was found (CD3(+): r = 0.592, p < 0.01; CD4(+): r = 0.501, p < 0.01). We also found a negative and significant correlation between weekly rhEPO doses and the number of CD4(+) T cells (r = -0.358, p < 0.05). In conclusion, HD procedure still contributes to the development of T-cell lymphopenia, at least in part, by apoptosis induction. It was also shown that rhEPO therapy is associated with the CD4(+) T-cell decline, possibly by immune modulation, eliminating atypical cells and helping to restore the CD4(+) T-cell subset. 相似文献
83.
Michael P. Farrell David J. Hughes Ian R. Berry David J. Gallagher Emily A. Glogowski Stewart J. Payne Michael J. Kennedy Róisín M. Clarke Susan A. White Cian B. Muldoon Fiona Macdonald Pauline Rehal Danielle Crompton Solvig Roring Sarah T. Duke Trudi McDevitt David E. Barton Shirley V. Hodgson Andrew J. Green Peter A. Daly 《Familial cancer》2012,11(3):509-518
Approximately 25 % of mismatch repair (MMR) variants are exonic nucleotide substitutions. Some result in the substitution of one amino acid for another in the protein sequence, so-called missense variants, while others are silent. The interpretation of the effect of missense and silent variants as deleterious or neutral is challenging. Pre-symptomatic testing for clinical use is not recommended for relatives of individuals with variants classified as ‘of uncertain significance’. These relatives, including non-carriers, are considered at high-risk as long as the contribution of the variant to disease causation cannot be determined. This results in continuing anxiety, and the application of potentially unnecessary screening and prophylactic interventions. We encountered a large Irish Lynch syndrome kindred that carries the c.544A>G (p.Arg182Gly) alteration in the MLH1 gene and we undertook to study the variant. The clinical significance of the variant remains unresolved in the literature. Data are presented on cancer incidence within five kindreds with the same germline missense variant in the MLH1 MMR gene. Extensive testing of relevant family members in one kindred, a review of the literature, review of online MMR mutation databases and use of in silico phenotype prediction tools were undertaken to study the significance of this variant. Clinical, histological, immunohistochemical and molecular evidence from these families and other independent clinical and scientific evidence indicates that the MLH1 p.Arg182Gly (c.544A>G) change causes Lynch syndrome and supports reclassification of the variant as pathogenic. 相似文献
84.
Ovarian cancer is an important health concern worldwide. The majority of patients present with advanced disease, and despite initial chemosensitivity, most relapse and die from their disease. Better therapeutic options are urgently required. Maximal surgical debulking in combination with platinum/taxane chemotherapy has been the standard of care in advanced ovarian cancer since the mid-1990s. Trials investigating the addition of a third chemotherapeutic agent have disappointingly failed to demonstrate benefit. Intra-peritoneal therapy demonstrated improvements in outcomes in some trials, but at the cost of increased toxicity and inconvenience. Encouragingly, prospective data has now demonstrated benefits with bevacizumab in both the first-line and relapsed settings; however, interpretation is complex, particularly considering recent data demonstrating non-inferiority of neo-adjuvant chemotherapy with delayed primary surgery, and other data demonstrating a substantial improvement in outcome as a result of first-line paclitaxel dose fractionation. This article reviews the recent advances in ovarian cancer treatment and discusses current management and key areas for future research. 相似文献
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88.
Fiona Dykes 《Health care for women international》2013,34(5):492-502
I conducted a longitudinal phenomenological study in England to explore the perceptions of 10 lactating women related to the nature of their breast milk and their ability to exclusively breast-feed their babies. The women viewed breast-feeding as a mechanical manufacturing process, and they carefully monitored the output of breast milk. Health care professionals contributed to the women's perceptions and displayed mechanistic assumptions in relation to breastfeeding, reflecting their enculturation through the biomedical paradigm. I present personal accounts to highlight the influence of two dominant Western ideologies--biomedical science and capitalism--upon women's perceptions of their breast milk. 相似文献
89.
90.
In part 1, published last month, causes and clinical features of congestive heart failure in infancy were discussed, and some of the more common malformations were illustrated. In this portion, principles of management and recommendations for specific therapy are presented. Particularly emphasized is digitalization, the most important step in treating the infant with heart failure. 相似文献