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51.
The prognostic significance of the serum CA 125 level was studied in 687 patients with invasive epithelial ovarian malignancies. The samples were collected preoperatively in 200 and postoperatively in 487 patients. Median follow-up was 27 months (range 3-84). The serum CA 125 level was elevated preoperatively in 90% of cases, with a median value of 429 U/mL. In patients with evidence of disease at the time of sampling, the CA 125 serum level correlated directly to tumor stage, tumor load, and histologic grade. Using Cox multivariate analysis, the preoperative serum CA 125 level had no independent prognostic significance, whereas the postoperative level did. In patients without residual disease after primary surgery, histologic type (P less than .0001), postoperative CA 125 level with 35 U/mL as the cutoff value (P = .0009), and tumor grade (P = .034) were independent prognostic factors for survival. For those with residual tumor after primary surgery, histologic type (P less than .0001), postoperative treatment (P = .0002), size of residual disease (P = .0005), and postoperative serum CA 125 level with 65 U/mL as a cutoff (P = .003) were independent prognostic factors.  相似文献   
52.
Several different genetic variants at chromosome 8q24 have been related to prostate, breast and colorectal cancer risk with evidence of region-specific risk differentials for various tumor types. We investigated the association between 15 polymorphisms located in 8q24 regions associated with cancer risk in a pooled analysis of 2587 colorectal adenoma cases, 547 colorectal cancer cases and 2798 controls of European descent from four studies. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the associations. Three polymorphisms (rs10808555, rs6983267 and rs7837328) located between 128.47 and 128.54 Mb were found to be associated with colorectal tumor risk. The association was strongest for the previously reported rs6983267 variant and was similar for both adenoma (OR(per allele) = 1.16, 95% CI: 1.07-1.25, P = 0.0002) and cancer (OR (per allele) = 1.17, 95% CI: 1.01-1.35, P = 0.03). The strength of the association of the regional haplotype containing variant alleles at rs10808555, rs6983267 and rs7837328 but not rs10505476 was greater than that of any single variant of both adenoma (OR = 1.27, P = 0.0001) and cancer (OR = 1.26, P = 0.03). The risk associated with rs6983267 was stronger for multiple adenomas (OR(per allele) = 1.29, P = 5.6 x 10(-6)) than for single adenoma (OR(per allele) = 1.10, P = 0.03) with P(heterogeneity) = 0.008. This study confirms the association between colorectal neoplasia and the 8q24 polymorphisms located between 128.47 and 128.54 Mb and suggests a role for these variants in the formation of multiple adenomas.  相似文献   
53.
The Harvard TMA Research Collaborative is a multi‐institutional registry‐based effort to study thrombotic microangiopathies (TMA). Laboratory and clinical parameters were recorded for 254 cases of suspected autoimmune thrombotic thrombocytopenic purpura (TTP). Patients with severe ADAMTS13 deficiency (activity ≤10%, N = 68) were more likely to be young, female and without a history of cancer treatment or transplantation. While all patients with severe deficiency were diagnosed with autoimmune TTP, those without severe deficiency frequently had disseminated intravascular coagulation, drug‐associated TMA and transplant‐related TMA. Patients with severe ADAMTS13 deficiency had superior overall survival at 360 d compared to those without severe deficiency (93·0% vs. 47·5%, P < 0·0001). Almost all patients with severe deficiency received therapeutic plasma exchange (TPE), but the use of TPE in patients with ADAMTS13 activity >10% varied significantly across the institutions in our consortium (13·2–63·8%, P < 0·0001). Nevertheless, 90‐d mortality was not different in patients with ADAMTS13 activity >10% between the three hospitals (P = 0·98). Our data show that patients with severe ADAMTS13 deficiency represent a clinically distinct cohort that responds well to TPE. In contrast, TMA without severe ADAMTS13 deficiency is associated with increased mortality that may not be influenced by TPE.  相似文献   
54.
Unfractionated heparin (UFH) plasma protein binding and elimination might be impaired in patients with chronic kidney disease (CKD—defined as creatinine clearance <60 ml/min). It is currently unknown at which UFH bolus dose persistent prolongation of activated partial thromboplastin time (aPTT) occurs in ST-segment elevation myocardial infarction (STEMI) patients with CKD. We investigated the effect of different UFH bolus doses on the first aPTT measured within 6 and 12 h after PPCI in 1071 STEMI patients with and without CKD undergoing primary percutaneous coronary intervention (PPCI) between 1-1-2003 and 31-07-2008. In the first 6 h after PPCI, aPTT ratio was 5.1 for patients with CKD versus 3.4 for those without (p < 0.001). The proportion of patients with markedly high aPTTs (aPTT ratio ≥ 4 times control) increased with increasing heparin bolus and beyond 130 IU/kg there was a marked difference between patients with and without CKD (74.1 and 42.3 % respectively, p < 0.001). By multivariable analysis, CKD was associated with an increased risk of markedly high aPTTs (odds ratio (OR) 2.04; 95 % confidence interval (CI) 1.27–3.27), driven largely by an increased risk of aPTT prolongation in patients treated with UFH boluses ≥130 IU/kg (OR 3.69; 95 % CI 1.85–7.36; p for interaction = 0.009). In conclusion, CKD is associated with severe persistent aPTT prolongation in STEMI patients undergoing PPCI, possibly due to impaired plasma protein binding and reduced UFH elimination. A lower heparin bolus dose might result in lower aPTTs and less bleeding complications in patients with CKD undergoing PPCI.  相似文献   
55.
Extracorporeal photopheresis (ECP) has been used for over 30 years in the treatment of erythrodermic cutaneous T-cell lymphoma (CTCL) and over 20 years for chronic graft-versus-host disease (cGVHD). The lack of prospective randomized trials has led to different centres having different patient selection criteria, treatment schedules, monitoring protocols and patient assessment criteria. ECP for CTCL and cGVHD is available only at six specialized centres across the U.K. In the recent Improving Outcomes Guidance the National Institute for Health and Clinical Excellence endorsed the use of ECP for CTCL and because of the complexity of treatment supported its use in specialized centres and also suggested the need for expansion of this service. In 2005 consultants and senior nurses from all U.K. sites and from Scandinavia formed a Photopheresis Expert Group. This group's first aim was to produce a consensus statement on the treatment of CTCL and cGVHD with ECP using evidence-based medicine and best medical practice, in order to standardize ECP eligibility, assessment and treatment strategies across the U.K.  相似文献   
56.
Digestive Diseases and Sciences - LVP is used to manage diuretic-resistant ascites in cirrhotic patients. Albumin administration prevents complications including acute kidney injury and...  相似文献   
57.
Digestive Diseases and Sciences - The optimal therapy for bleeding-related gastric varices is still a controversial topic. There is a paucity of literature that comprehensively summarizes the...  相似文献   
58.
59.
Cross-presentation is increasingly recognized as a key mechanism by which specific antigen-presenting cells (APCs) activate the cellular immune system against virally infected or neoplastic cells. These APCs have the capacity to acquire exogenous proteins by phagocytosis or endocytosis, derive antigenic peptides, and then cross-present them in the context of class I major histocompatibility complex molecules. Because APCs provide both an antigenic stimulus and costimulatory signals, they can effectively activate naive CD8+ T lymphocytes, resulting in a brisk cellular immune response. The precise cellular pathways that permit an exogenous antigen to be presented in the context of class I major histocompatibility complex is the focus of intense investigation that has illuminated our understanding of the cell biology of APCs. This article reviews our understanding of how APCs cross-present antigen, illustrating how this process differs from the canonical pathways of antigen presentation. We define the central players required for cross-presentation and then focus on recent studies that reveal the molecular mechanisms underlying this phenomenon. Understanding these mechanisms will likely inform the development of effective cell-based vaccines and other cellular immunotherapies and is therefore of interest to practitioners of transfusion medicine.  相似文献   
60.
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