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61.
After proctocolectomy with ileal pouch-anal anastomosis (IPAA) patients have increased stool frequency and intermittently
use antidiarrheal medication. In addition to other factors, gastrointestinal transit time (MTT) could influence stool frequency.
The aim of this study was to investigate how MTT changes after IPAA and to study whether MTT has an influence on daily stool
frequency. In a prospective trial MTT was investigated with the lactulose breath test in 12 patients undergoing surgery for
chronic ulcerative colitis (CUC) or familial adenomatous polyposis coli (FAPC) at different stages: before proctocolectomy,
after IPAA with loop ileostomy, and 3 months and 1 year after ileostomy closure. MTT was also measured in 12 patients with
IPAA, 12 patients with subtotal colectomy and ileorectal anastomosis (IRA), and 8 patients with conventional proctocolectomy
and Brooke ileostomy (CPC) several years after surgery. Twelve healthy volunteers served as controls. Before IPAA, MTT was
prolonged in CUC versus FAPC and controls. After restoration of gut continuity MTT was markedly accelerated. After 1 year
MTT was slowed again, though values before proctocolectomy and those in controls were not reached. Several years after surgery
MTT was significantly prolonged in IPAA and IRA versus controls. In CPC, MTT could not be determined by lactulose breath test.
Stool frequency showed an inverse correlation to MTT in IPAA. In conclusion, this study shows that orocecal and oropouch transit
are accelerated in the early postoperative period after (procto)colectomy but prolonged in the long-term course. Adaptation
of the small bowel takes longer than 1 year. Impairment of stool frequency may be partly due to this adaptation. 相似文献
62.
Preoperative Evaluation of Pancreatic Masses with Positron Emission Tomography Using 18F-fluorodeoxyglucose: Diagnostic Limitations 总被引:7,自引:0,他引:7
Sendler A Avril N Helmberger H Stollfuss J Weber W Bengel F Schwaiger M Roder JD Siewert JR 《World journal of surgery》2000,24(9):1121-1129
Identification of pancreatic cancer in patients presenting with an enlarged pancreatic mass is a major diagnostic problem.
Positron emission tomography (PET) using the radiolabeled glucose analogue 18F-fluorodeoxyglucose (FDG) has been suggested to provide excellent accuracy for noninvasive determination of suspicious pancreatic
masses. We conducted a prospective study to verify these results. Forty-two patients admitted for pancreatic surgery underwent
PET scanning. Image analysis was based on visual film evaluation and quantification of regional tracer uptake. PET imaging
was visually analyzed by three observers blinded for the results of other diagnostic tests; they qualitatively graded the
scans using a five-point scale (I = low to V = high) for the presence and intensity of focal FDG uptake. Diagnosis was proven
by histology (n= 38) or follow-up (n= 4). Furthermore, the results of PET were compared with helical computed tomography (CT) and conventional ultrasonography
(US), done during the routine diagnostic workup before pancreatic cancer surgery. Regarding only the results with scores of
IV and V as positive for representing definite malignancy yielded a sensitivity of 71% and a specificity of 64% for film reading.
Quantification of regional tracer uptake contributed no significant diagnostic advantage for differentiation between benign
and malignant tumors. Helical CT revealed a sensitivity of 74% and a specificity of 45.5% and abdominal US 56% and 50%, respectively.
We concluded that PET imaging provides only fair diagnostic accuracy (69%) for characterizing enlarged pancreatic masses.
PET does not allow exclusion of malignant tumors. In doubtful cases, the method must be combined with other imaging modalities,
such as helical CT. The results indicate that the number of invasive procedures is not significantly reduced by PET imaging. 相似文献
63.
Udo Vanhoefer Mitra Tewes Federico Rojo Olaf Dirsch Norbert Schleucher Oliver Rosen Joachim Tillner Andreas Kovar Ada H Braun Tanja Trarbach Siegfried Seeber Andreas Harstrick José Baselga 《Journal of clinical oncology》2004,22(1):175-184
PURPOSE: To investigate the safety and tolerability and to explore the pharmacokinetic and pharmacodynamic profile of the humanized antiepidermal growth factor receptor monoclonal antibody EMD72000 in patients with solid tumors that express epidermal growth factor receptor (EGFR). PATIENTS AND METHODS: This was a phase I dose-escalation trial of EMD72000 in patients with advanced, EGFR-positive, solid malignancies that were not amenable to any established chemotherapy or radiotherapy treatment. EMD72000 was administered weekly without routine premedication until disease progression or unacceptable toxicity. RESULTS: Twenty-two patients were treated with EMD72000 at five different dose levels (400 to 2,000 mg/wk). National Cancer Institute common toxicity criteria grade 3 headache and fever occurring after the first infusion were dose limiting at 2,000 mg/wk; thus, the maximum-tolerated dose was 1,600 mg/wk. No other severe side effects, especially no allergic reactions or diarrhea, were observed. Acneiform skin reaction was the most common toxicity, but it was mild, with grade 1 in 11 patients (50%) and grade 2 in three patients (14%). Pharmacokinetic analyses demonstrated a predictable pharmacokinetic profile for EMD72000. Pharmacodynamic studies on serial skin biopsies revealed that EMD72000 effectively abrogated EGFR-mediated cell signaling (eg, reduced phosphorylation of EGFR and mitogen-activated protein kinase), with no alteration in total EGFR protein. Objective responses (23%; 95% CI, 8% to 45%) and disease stabilization (27%; 95% CI, 11% to 50%) were achieved at all dose levels, and responding patients received treatment for up to 18 months without cumulative toxicity. CONCLUSION: Treatment with EMD72000 was well tolerated and showed evidence of activity in heavily pretreated patients with EGFR-expressing tumors. EMD72000 at the investigated doses significantly inhibited downstream EGFR-dependent processes. 相似文献
64.
Toshifumi Ozaki Silke Flege Matthias Kevric Norbert Lindner Rainer Maas Günter Delling Rudolf Schwarz Arthur R von Hochstetter Mechthild Salzer-Kuntschik Wolfgang E Berdel Heribert Jürgens G Ulrich Exner Peter Reichardt Regine Mayer-Steinacker Volker Ewerbeck Rainer Kotz Winfried Winkelmann Stefan S Bielack 《Journal of clinical oncology》2003,21(2):334-341
PURPOSE: To define patients and tumor characteristics as well as therapy results, patients with pelvic osteosarcoma who were registered in the Cooperative Osteosarcoma Study Group (COSS) were analyzed. PATIENTS AND METHODS: Sixty-seven patients with a high-grade pelvic osteosarcoma were eligible for this analysis. Fifteen patients had primary metastases. All patients received chemotherapy according to COSS protocols. Thirty-eight patients underwent limb-sparing surgery, 12 patients underwent hemipelvectomy, and 17 patients did not undergo definitive surgery. Eleven patients received irradiation to the primary tumor site: four postoperatively and seven as the only form of local therapy. RESULTS: Local failure occurred in 47 of all 67 patients (70%) and in 31 of 50 patients (62%) who underwent definitive surgery. Five-year overall survival (OS) and progression-free survival rates were 27% and 19%, respectively. Large tumor size (P =.0137), primary metastases (P =.0001), and no or intralesional surgery (P <.0001) were poor prognostic factors. In 30 patients with no or intralesional surgery, 11 patients with radiotherapy had better OS than 19 patients without radiotherapy (P =.0033). Among the variables, primary metastasis, large tumor, no or intralesional surgery, no radiotherapy, existence of primary metastasis (relative risk [RR] = 3.456; P =.0009), surgical margin (intralesional or no surgical excision; RR = 5.619; P <.0001), and no radiotherapy (RR = 4.196; P =.0059) were independent poor prognostic factors. CONCLUSION: An operative approach with wide or marginal margins improves local control and OS. If the surgical margin is intralesional or excision is impossible, additional radiotherapy has a positive influence on prognosis. 相似文献
65.
Steffen Robert Tornieporth Nadia Costa Clemens Sue-Ann Chatterjee Santanu Cavalcanti Ana-Maria Collard Françoise De Clercq Norbert DuPont Herbert L. von Sonnenburg Frank 《Journal of travel medicine》2004,11(4):231-238
Background Recent epidemiologic data on travelers— diarrhea (TD) are essential for the evaluation of conventional and future prophylactic and therapeutic measures.
Methods To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.
Results Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.
Conclusions TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve. 相似文献
Methods To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.
Results Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.
Conclusions TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve. 相似文献
66.
Weidong He Luc Van Puyvelde Norbert De Kimpe Luc Verbruggen Kristel Anthonissen Mark Van der Flaas Jan Bosselaers Simon G Mathenge Francis P Mudida 《Phytotherapy research : PTR》2002,16(1):66-70
Bioassay-guided fractionation of the dichloromethane extracts of the roots and the bark of Zanthoxylum usambarense led to the isolation of two physiologically active compounds, i.e. canthin-6-one 1 (fungicide) and pellitorine 4 (insecticide). Together with oxychelerythrine 2, norchelerythrine 3, (+)-sesamin 5 and (+)-piperitol-3,3-dimethylallyl ether 6, they were isolated for the first time from this plant. 相似文献
67.
68.
Lara Schorn Anna Sine Karin Berr Jrg Handschel Rita Depprich Norbert R. Kübler Christoph Sproll Majeed Rana Julian Lommen 《Materials》2022,15(14)
Alloplastic and xenogeneic bone grafting materials are frequently used for bone augmentation. The effect of these materials on precursor cells for bone augmentation is yet to be determined. The aim of this study was to ascertain, in vitro, how augmentation materials influence the growth rates and viability of human unrestricted somatic stem cells. The biocompatibility of two xenogeneic and one alloplastic bone graft was tested using human unrestricted somatic stem cells (USSCs). Proliferation, growth, survival and attachment of unrestricted somatic stem cells were monitored after 24 h, 48 h and 7 days. Furthermore, cell shape and morphology were evaluated by SEM. Scaffolds were assessed for their physical properties by Micro-CT imaging. USSCs showed distinct proliferation on the different carriers. Greatest proliferation was observed on the xenogeneic carriers along with improved viability of the cells. Pore sizes of the scaffolds varied significantly, with the xenogeneic materials providing greater pore sizes than the synthetic inorganic material. Unrestricted somatic stem cells in combination with a bovine collagenous bone block seem to be very compatible. A scaffold’s surface morphology, pore size and bioactive characteristics influence the proliferation, attachment and viability of USSCs. 相似文献
69.
Thorsten Zenz Markus Kreuz Maxi Fuge Wolfram Klapper Heike Horn Annette M. Staiger Doris Winter Hanne Helfrich Jennifer Huellein Martin‐Leo Hansmann Harald Stein Alfred Feller Peter M?ller Norbert Schmitz Lorenz Trümper Markus Loeffler Reiner Siebert Andreas Rosenwald German Ott Michael Pfreundschuh Stephan Stilgenbauer for the German High‐Grade Non‐Hodgkin Lymphoma Study Group 《International journal of cancer. Journal international du cancer》2017,141(7):1381-1388
TP53 is mutated in 20–25% of aggressive B‐cell lymphoma (B‐NHL). To date, no studies have addressed the impact of TP53 mutations in prospective clinical trial cohorts. To evaluate the impact of TP53 mutation to current risk models in aggressive B‐NHL, we investigated TP53 gene mutations within the RICOVER‐60 trial. Of 1,222 elderly patients (aged 61–80 years) enrolled in the study and randomized to six or eight cycles of CHOP‐14 with or without Rituximab (NCT00052936), 265 patients were analyzed for TP53 mutations. TP53 mutations were demonstrated in 63 of 265 patients (23.8%). TP53 mutation was associated with higher LDH (65% vs. 37%; p < 0.001), higher international prognostic index‐Scores (IPI 4/5 27% vs. 12%; p = 0.025) and B‐symptoms (41% vs. 24%; p = 0.011). Patients with TP53 mutation were less likely to obtain a complete remission CR/CRu (CR unconfirmed) 61.9% (mut) vs. 79.7% (wt) (p = 0.007). TP53 mutations were associated with decreased event‐free (EFS), progression‐free (PFS) and overall survival (OS) (median observation time of 40.2 months): the 3 year EFS, PFS and OS were 42% (vs. 60%; p = 0.012), 42% (vs. 67.5%; p < 0.001) and 50% (vs. 76%; p < 0.001) for the TP53 mutation group. In a Cox proportional hazard analysis adjusting for IPI‐factors and treatment arms, TP53 mutation was shown to be an independent predictor of EFS (HR 1.5), PFS (HR 2.0) and OS (HR 2.3; p < 0.001). TP53 mutations are independent predictors of survival in untreated patients with aggressive CD20+ lymphoma. TP53 mutations should be considered for risk models in DLBCL and strategies to improve outcome for patients with mutant TP53 must be developed. 相似文献
70.
Dussan C Zubor P Fernandez M Yabar A Szunyogh N Visnovsky J 《Gynecologic and obstetric investigation》2008,65(3):206-211
Spontaneous regression of malignant tumors is a rare event. It is defined as partial or total disappearance of a proven malignant tumor without adequate medical treatment. The causes of this phenomenon are various. Nevertheless, malignant tumors do regress occasionally for no apparent reason, as evidenced by many clinical observations. We report a case of a 68-year-old woman, who was presented with a several-month history of a painless firm lump, initially of 1 cm in diameter and growing to a large solid regular tumor of 2.5 x 2.5 cm in size, in the upper outer quadrant of her right breast. Preoperative histopathological diagnosis revealed ductal invasive carcinoma. Later on, while awaiting surgical treatment, she suffered an arm injury requiring a 1-month delay of surgery. After recovery, on the date of surgery the tumor disappeared, and, in addition, it was not found in tissue specimens obtained from quadrantectomy. After 78 months of follow-up there was no evidence of relapse. In this report, we discuss clinical and histopathological findings, patient management and possible mechanisms of cancer regression. 相似文献