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Mittermaier C Kurz M Rosskopf K Hoecker P Moeschl P Gangl A Gasche C 《Zeitschrift für Gastroenterologie》1999,37(12):1169-1173
BACKGROUND: Surgery in inflammatory bowel disease (IBD) is frequently associated with need for perioperative blood transfusions carrying the potential risk of infection. Autologous blood donation is often limited by IBD-associated anemia which is reversible by intravenous iron and erythropoietin. We therefore tested the feasibility of autologous blood donation in IBD. METHODS: Six patients (five Crohn's disease, one ulcerative colitis) with indication for elective bowel resection were treated after informed consent was obtained. Two to four blood donations were scheduled during four weeks prior to surgery. Once a week 350-450 ml of blood were collected from patients with a hemoglobin level above 11.0 g/dl. After each donation 200 mg of iron saccharate diluted in 0.9% saline were given to all patients intravenously as substitute for donation-related iron loss. Patients with preexisting anemia or C-reactive protein above 2.0 mg/dl received concomitant erythropoietin. RESULTS: The scheduled number of packed red cells was donated successfully by four patients. Due to low hemoglobin levels two patients donated one unit less than intended. Four patients received autologous blood transfusions intra- or postoperatively. No patient needed homologous blood. No serious adverse events were observed during blood donations, perioperatively, and during the one year follow-up period. CONCLUSION: Preoperative autologous blood donation is save and feasible in IBD patients with elective bowel resection. 相似文献
64.
PATHOPHYSIOLOGY AND THERAPY: Left ventricular hypertrophy represents an important factor determining the prognosis of hypertensive patients. Hypertrophy as identified by electrocardiography (Table 1) or echocardiography (Table 2) characterizes patients with a significantly increased risk of mortality and arrhythmia. From the pathophysiological point of view this is based on hypertrophy of the media in resistance vessels, on interstitial fibrosis, on a reduced coronary flow reserve and on the occurrence of ischemia (Figure 1). The diastolic and (later) systolic function of the heart are disturbed (Figures 2 to 4). Antihypertensive therapy with beta blockers and diuretics leads to a reduction of left ventricular mass by 5-8%, with ACE-inhibitors and AT-blockers by 13% (Figure 5). Particularly ACE-inhibitors can effectively reverse of the above mentioned pathological processes. Regression of hypertrophy goes along with an improved prognosis and a reduction of atrial and ventricular arrhythmias (Figure 6). A symptomatic treatment of arrhythmias should always be accompanied by medical therapy aimed at regression of hypertrophy. Optimal therapy results in normalizes of blood pressure, leads to a regression of hypertrophy and induces cardiac reparation, which in turn improve left ventricular function, reduces microvascular ischemia stress and arrhythmias. These therapeutic desiderates are also pertinent for hypertensive heart disease in the prehypertrophic state, as in juvenile hypertension. 相似文献
65.
F. S. Liotti A. R. Menghini P. Guerrieri V. Talesa M. Bodo 《Journal of cancer research and clinical oncology》1984,108(2):230-232
Summary The effects of AA and DHA on ATP C+ cell multiplication in vitro were studied by measuring incorporation of 3H thymidine into DNA. The results obtained demonstrate that both AA and DHA have the same effects: they favor cell multiplication at low doses and inhibit it at high doses. Experiments carried out with serial doses of both these substances revealed that AA is more efficient in determining both stimulating and inhibiting effects. The lesser efficiency of DHA may be attributed to its limited stability in culture medium. Studies on the effect of high doses of AA and DHA added to the culture medium in single or fractionated doses revealed that fractionated administration is more efficient in inhibiting cell multiplication than single administration.Abbreviations AA
ascorbic acid
- DHA
dehydroascorbic acid
- ATP C+
ascites tumor Perugia in Balb C+ mice
- GSH
reduced glutathione 相似文献
66.
Flavonoid quercetin, but not apigenin or luteolin, induced apoptosis in human myeloid leukemia cells and their resistant variants 总被引:1,自引:0,他引:1
Flavonoids and their in vivo metabolites are neuroprotective, cardioprotective and chemopreventive agents acting as hydrogen-donating antioxidants or modulators functioning at protein kinase and lipid signaling pathways. In presented study treatments of human leukemia cells HL60 and their MDR-1 resistant subline HL60/VCR by flavonoids apigenin (API), luteolin (LUT), quercetin (QU) and anticancer drug doxorubicin (DOX) are reported. Of all flavonoids used only QU treatments led in both cell lines to DNA fragmentation, cleavage of poly (ADP- ribose) polymerase (PARP), up-regulation of proapoptotic Bax and posttranslational modification (phosphorylation) of antiapoptotic Bcl-2. Cytochrome c and p21WAF1/CIP1 levels remained unchanged in these cells. Furthermore, treatments of both cell lines by QU and in its combined application with DOX increased phosphorylation of ERK, while Akt-1 and phosphorylated Akt-1 levels were not changed. All these events resulted in effective induction of apoptosis associated with down-regulation of P-glycoprotein in resistant cells. Presented results suggest that in human leukemia cells QU is a potent regulator of the cell apoptotic program associated with the modulation of several signaling molecules. 相似文献
67.
A prospective study on incidence and risk factors of arteriovenous fistulae following transfemoral cardiac catheterization 总被引:4,自引:0,他引:4
BACKGROUND: A potentially harmful complication of cardiac catheterization is the arteriovenous fistula. Precise knowledge of possible factors predisposing for acquisition of iatrogenic AV-fistulae could enable cardiologists to perform a risk stratification for cardiac patients prior to catheterization. METHODS: Over a period of 2 years, 10,271 consecutive patients who underwent cardiac catheterization were included in this study. Auscultation of a new femoral bruit was followed by a duplex scan to confirm the suspected diagnosis of an AVF. Every patient was investigated on the day after catheterization. RESULTS: The incidence of iatrogenic AVF was 0.86%. A multivariate regression analysis revealed five significant and independent risk factors: (1) procedural heparin dosage >or=12,500 IU (Odds Ratio (OR)=2.88), (2) coumadin therapy (OR=2.34), (3) puncture of the left groin (OR=2.21), (4) arterial hypertension (OR=1.86) and (5) female gender (OR=1.84). Coronary angioplasty (instead of diagnostic procedure), size and number of sheaths, age and body mass index did not significantly affect the incidence of AVF. CONCLUSIONS: The overall incidence of AV-fistulae following cardiac catheterization approximates 1%. Determination of significant risk factors will facilitate identification of patients at risk for iatrogenic arteriovenous fistulae prior to cardiac catheterization and thus help to develop strategies to reduce the incidence of AV-fistulae. 相似文献
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Artur Hahn Julia Bode Allen Alexander Kianush Karimian-Jazi Katharina Schregel Daniel Schwarz Alexander C Sommerkamp Thomas Krüwel Amir Abdollahi Wolfgang Wick Michael Platten Martin Bendszus Bjrn Tews Felix T Kurz Michael O Breckwoldt 《Journal of cerebral blood flow and metabolism》2021,41(7):1536
Three-dimensional assessment of optically cleared, entire organs and organisms has recently become possible by tissue clearing and selective plane illumination microscopy (“ultramicroscopy”). Resulting datasets can be highly complex, encompass over a thousand images with millions of objects and data of several gigabytes per acquisition. This constitutes a major challenge for quantitative analysis. We have developed post-processing tools to quantify millions of microvessels and their distribution in three-dimensional datasets from ultramicroscopy and demonstrate the capabilities of our pipeline within entire mouse brains and embryos. Using our developed acquisition, segmentation, and analysis platform, we quantify physiological vascular networks in development and the healthy brain. We compare various geometric vessel parameters (e.g. vessel density, radius, tortuosity) in the embryonic spinal cord and brain as well as in different brain regions (basal ganglia, corpus callosum, cortex). White matter tract structures (corpus callosum, spinal cord) showed lower microvascular branch densities and longer vessel branch length compared to grey matter (cortex, basal ganglia). Furthermore, we assess tumor neoangiogenesis in a mouse glioma model to compare tumor core and tumor border. The developed methodology allows rapid quantification of three-dimensional datasets by semi-automated segmentation of fluorescently labeled objects with conventional computer hardware. Our approach can aid preclinical investigations and paves the way towards “quantitative ultramicroscopy”. 相似文献
70.
Constanze A. Jakwerth Adam M. Chaker Ferdinand Guerth Madlen Oelsner Lisa Pechtold Lynn S. zur Bonsen Julia T. Ullmann Susanne Krauss-Etschmann Anna Erb Josephine Kau Mirjam Plaschke Marlene Winkler Alexandra Kurz Antonia Kloss Julia Esser-von Bieren Carsten B. Schmidt-Weber Ulrich M. Zissler 《Clinical and experimental allergy》2021,51(12):1577-1591