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81.
The ABCOM 1 transtracheal Doppler (TTD) has been developed as a non-invasive cardiac output monitor. With this device, cardiac output is continuously calculated from ascending aortic blood flow velocity and aortic diameter obtained via an ultrasound transducer incorporated into the tip of an endotracheal tube. We evaluated the clinical use of the ABCOM 1 monitor and compared cardiac outputs obtained using the TTD system with simultaneous thermodilution (TD) measurements. We found the operation of the ABCOM 1 monitor to be difficult and time-consuming. In our operating rooms, acceptable Doppler signal quality was difficult to obtain. There was no correlation between 36 simultaneously obtained TTD and TD cardiac output measurements. The average difference between measurement techniques and the limits of agreement were unacceptably large (mean difference = 3.04 L.min-1, mean +/- 2 SD = -6.04 to 12.48 L.min-1). Separately analyzing only those measurements during which Doppler signal quality was adequate did not improve agreement between TTD and TD measurements. On the basis of these findings, TTD cannot be recommended as a clinical cardiac output measurement technique. 相似文献
82.
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
83.
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
84.
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
85.
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
86.
Allergic airway diseases induced by low molecular weight (LMW) chemicals, including trimellitic anhydride (TMA), are characterized by airway mucus hypersecretion and an infiltration of eosinophils and lymphocytes. Many experimental models have linked LMW chemical-induced allergic airway disease to Th2 cytokines. Most murine models, however, use dermal exposure to sensitize mice. The present study was designed to test the hypothesis that intranasal sensitization and challenge with the known chemical respiratory allergen TMA, but not the nonrespiratory sensitizers dinitrochlorobenzene (DNCB) and oxazolone (OXA), will induce characteristic features of LMW chemical-induced allergic airway disease in the nasal and pulmonary airways. A/J mice were intranasally sensitized and challenged with TMA, DNCB, or OXA. Only mice that were intranasally sensitized and challenged with TMA had a marked allergic rhinitis with an influx of eosinophils, lymphocytes, and plasma cells, increased intraepithelial mucusubstances, and a regenerative hyperplasia. Cytokine mRNA levels in the nasal airway of TMA treated mice also revealed an increase in the mRNA levels of the Th2 cytokines IL-4, IL-5, and IL-13, but no change in the level of the Th1 cytokine IFN-gamma. No lesions were found in the nasal airways of mice exposed to DNCB or OXA. TMA increased lung-derived IL-5 mRNA while DNCB and OXA caused no change in lung-derived cytokine mRNA levels. Both TMA and DNCB caused increases in total serum IgE, unlike OXA-exposed mice. However, no adverse alterations were found microscopically in the lungs of mice treated with TMA, DNCB, or OXA. This study is the first to demonstrate that intranasal administration of a known chemical respiratory allergen is an effective method of sensitization resulting in the hallmark features of allergic rhinitis after challenge with a concomitant increase in nasal airway-derived Th2 cytokine mRNA, lung-derived IL-5 mRNA, and total serum IgE. In contrast, DNCB and OXA failed to elicit the pathologic changes in the nasal airways and cytokine changes in the lung. This model may be useful for identifying other chemical respiratory allergens. 相似文献
87.
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
88.
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
89.
90.
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