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101.
OBJECTIVE: To assess the treatment of peripancreatic fluid collections or abscess with percutaneous catheter drainage (PCD). SUMMARY BACKGROUND DATA: Surgical intervention has been the mainstay of treatment for infected peripancreatic fluid collections and abscesses. Increasingly, PCD has been used, with mixed results reported in the literature. METHODS: A retrospective chart review of 1993 to 1997 was performed on 82 patients at a tertiary care public teaching hospital who had computed tomography-guided aspiration for suspected infected pancreatic fluid collection or abscess. Culture results, need for subsequent surgical intervention, length of stay, and death rate were assessed. RESULTS: One hundred thirty-five aspirations were performed in 82 patients (57 male patients, 25 female patients) with a mean age of 40 years (range 17-68). The etiologies were alcohol (41), gallstones (32), and other (9). The mean number of Ranson's criteria was four (range 0-9). All patients received antibiotics. Forty-eight patients had evidence of pancreatic necrosis on computed tomography scan. Cultures were negative in 40 patients and positive in 42. Twenty-five of the 42 culture-positive patients had PCD as primary therapy, and 6 required subsequent surgery. Eleven patients had primary surgical therapy, and five required subsequent surgery. Six patients were treated with only antibiotics. The death rates were 12% for culture-positive patients and 8% for the entire 82 patients. CONCLUSIONS: Historically, patients with positive peripancreatic aspirate culture have required operation. This series reports an evolving strategy of reliance on catheter drainage. PCD should be considered as the initial therapy for culture-positive patients, with surgical intervention reserved for patients in whom treatment fails.  相似文献   
102.
目的 近年来,医学、外科类文献有向循证医学方向发展的趋势.本研究旨在检测已发表的整形外科类文章的证据水平.方法 回顾性分析<整形再造外科杂志(Plastic and Reconstructive Surgery,PRS)><整形外科年鉴(Annals of Plastic Surgery,Annals)><整形再造与美容外科杂志(Journal of Plastic,Reconstructive,and Aesthetic Surgery,JPRAS)><美国美容外科杂志(American Journal of Aesthetic Surgery,Aesthetic)>4本主要的整形外科类杂志2009年1~12月刊载论文利用证据的水平.结果 在1759篇文献中,共有726篇(41%)纳入本研究标准(排除动物实验、尸体研究、基础医学、文献复习、继续教育和信函等方面文献).将选中的文献根据其证据水平进行分级(Ⅰ~Ⅳ级;Ⅰ级,证据水平最高,如随机对照研究;Ⅳ级,证据水平最低,如病例报告).4本杂志的平均证据水平分别为:PRS=3.05,Aesthetic=3.11,JPRAS=3.35,Annals=3.31.4本杂志的平均证据水平,除了JPRAS与Aesthetic的差异无统计学意义外,余者差异均有统计学意义(P<0.05).本研究纳入标准的文献,只有2.2%的证据水平为Ⅰ级.结论 4本杂志的平均证据水平为3.2(Ⅲ级水平).为了使整形外科专业加入到高水平循证医学行列,我们应当在今后的工作中着重强调随机对照研究的应用.  相似文献   
103.

Background  

Pancreatic fistula (PF) is an important factor responsible for the considerable morbidity associated with pancreaticoduodenectomy (PD). There have been many techniques proposed for the reconstruction of pancreatic digestive continuity to prevent fistula formation but which is best is still highly debated. We carried out a systematic review and meta-analysis to determine the effectiveness of methods of anastomosis after PD.  相似文献   
104.
Treatment with isolated allogeneic mesenchymal cells has the potential to enhance the therapeutic effects of conventional bone marrow transplantation in patients with genetic disorders affecting mesenchymal tissues, including bone, cartilage, and muscle. To demonstrate the feasibility of mesenchymal cell therapy and to gain insight into the transplant biology of these cells, we used gene-marked, donor marrow-derived mesenchymal cells to treat six children who had undergone standard bone marrow transplantation for severe osteogenesis imperfecta. Each child received two infusions of the allogeneic cells. Five of six patients showed engraftment in one or more sites, including bone, skin, and marrow stroma, and had an acceleration of growth velocity during the first 6 mo postinfusion. This improvement ranged from 60% to 94% (median, 70%) of the predicted median values for age- and sex-matched unaffected children, compared with 0% to 40% (median, 20%) over the 6 mo immediately preceding the infusions. There was no clinically significant toxicity except for an urticarial rash in one patient just after the second infusion. Failure to detect engraftment of cells expressing the neomycin phosphotransferase marker gene suggested the potential for immune attack against therapeutic cells expressing a foreign protein. Thus, allogeneic mesenchymal cells offer feasible posttransplantation therapy for osteogenesis imperfecta and likely other disorders originating in mesenchymal precursors.  相似文献   
105.
106.
Resveratrol is a naturally occurring phytoalexin with antioxidant activity. The chemopreventive effects of resveratrol against various types of cancer are well known, though the underlying molecular mechanisms of its action are still not identified. Hepatocellular carcinoma (HCC) is a one of the most lethal malignancies and there is no effective treatment till date. It is known that cyclin D1 is overexpressed in liver cancers. Accordingly we have studied the chemopreventive effects of resveratrol on cyclin D1 expression and the signaling pathways that regulate cyclin D1 in HepG2 cells. Flow cytometry and PCNA western blot data showed that resveratrol inhibits proliferation of HepG2 cells. Also, resveratrol treatment downregulated cyclin D1 as well as p38 MAP kinase, Akt and Pak1 expression and activity in HepG2 cells, suggesting that growth inhibitory activity of resveratrol is associated with the downregulation of cell proliferation and survival pathways. Furthermore, resveratrol treated cells showed increase in ERK activity suggesting possible sensitization to apoptosis. Thus in the present study, we report a three-dimensional relationship between the growth inhibitory effects of resveratrol – decrease in the levels of cyclin D1 – and downregulation of cell proliferation and survival pathways in HepG2 cells leading to cellular degenerative changes. These observations suggest that resveratrol has good potential as effective chemopreventive agent against liver cancer and warrant further studies.  相似文献   
107.
Background and Aims: Disease recurrence following transplantation occurs in 20–45% of patients with autoimmune hepatitis (AIH). Factors associated with an increased risk of recurrence include human leukocyte antigen (HLA) DR3 and HLA DR4 positivity, inadequate immunosuppression, and severity of inflammation in the native liver. Titers of several autoantibodies can be elevated in patients with AIH, including antinuclear antibody (ANA) and antismooth muscle antibody (SMA); however, it is unclear whether or not the degree of elevation influences the risk of disease recurrence following transplantation. Methods: We conducted a retrospective study to evaluate the potential impact of pretransplant titers on post‐transplant outcomes for patients with AIH. Sixty‐three patients with AIH who underwent 72 liver transplants between 1 January 1989 and 1 January 2009 were included, with a median follow up of 10 months. Patients were divided into group A (ANA or SMA ≥ 1 : 160) and group B (titers ≤ 1 : 160). Results: There was no significant difference in the recurrence rates or death between patients in groups A and B, respectively. Only race appeared to impact outcomes, with African American patients having a higher incidence of death and recurrent disease post‐transplant compared to other ethnicities. Conclusions: Based on our findings, pretransplant ANA and SMA levels do not appear to impact recurrence rates or outcomes following liver transplantation for AIH.  相似文献   
108.
In cystic fibrosis (CF), a lack of functional CF transmembrane conductance regulator (CFTR) chloride channels causes defective secretion by submucosal glands (SMGs), leading to persistent bacterial infection that damages airways and necessitates tissue repair. SMGs are also important niches for slow-cycling progenitor cells (SCPCs) in the proximal airways, which may be involved in disease-related airway repair. Here, we report that calcitonin gene–related peptide (CGRP) activates CFTR-dependent SMG secretions and that this signaling pathway is hyperactivated in CF human, pig, ferret, and mouse SMGs. Since CGRP-expressing neuroendocrine cells reside in bronchiolar SCPC niches, we hypothesized that the glandular SCPC niche may be dysfunctional in CF. Consistent with this hypothesis, CFTR-deficient mice failed to maintain glandular SCPCs following airway injury. In wild-type mice, CGRP levels increased following airway injury and functioned as an injury-induced mitogen that stimulated SMG progenitor cell proliferation in vivo and altered the proliferative potential of airway progenitors in vitro. Components of the receptor for CGRP (RAMP1 and CLR) were expressed in a very small subset of SCPCs, suggesting that CGRP indirectly stimulates SCPC proliferation in a non-cell-autonomous manner. These findings demonstrate that CGRP-dependent pathways for CFTR activation are abnormally upregulated in CF SMGs and that this sustained mitogenic signal alters properties of the SMG progenitor cell niche in CF airways. This discovery may have important implications for injury/repair mechanisms in the CF airway.  相似文献   
109.
110.
Assessment of 54 biomarkers for biopsy-detectable prostate cancer.   总被引:1,自引:0,他引:1  
OBJECTIVE: We analyzed the association of 54 biomarkers from seven classes including adipokines, immune response metalloproteinases, adhesion molecules, and growth factors with prostate cancer risk adjusting for the Prostate Cancer Prevention Trial (PCPT) risk score. METHODS: A total of 123 incident prostate cancer cases and 127 age-matched controls were selected from subjects in the San Antonio Center for Biomarkers of Risk of Prostate Cancer cohort study. Prediagnostic serum concentrations were measured in the sample collected at baseline using LabMAP technology. The odds ratios (OR) of prostate cancer risk associated with serum concentrations of 54 markers were estimated using univariate conditional logistic regression before and after adjustment for the PCPT risk score. Two-way hierarchical unsupervised clustering techniques were used to evaluate whether the 54-marker panel distinguished cases from controls. RESULTS: Vascular endothelial growth factor, resistin, interleukin 1Ra (IL-1Ra), granulocyte colony-stimulating factor, matrix metalloproteinase-3, plasminogen activator inhibitor, and kallikrein-8 were statistically significantly (P < 0.05) underexpressed in prostate cancer cases, and alpha-fetoprotein was statistically significantly overexpressed in prostate cancer cases, but all had area underneath the receiver-operating characteristic curve <60%; none were statistically significant adjusting for multiple comparisons (P < 0.0008) or after adjustment for the PCPT risk score. Statistical clustering of patients by the marker panel did not distinguish a separate group of cases from controls. CONCLUSIONS: This age-matched case-control study did not support findings of increased diagnostic potential from a 54-marker panel when compared with the conventional risk factors incorporated in the PCPT risk calculator. Future discovery of new biomarkers should always be tested and compared against conventional risk factors before applying them in clinical practice.  相似文献   
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