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71.
Zusammenfassung In einer prospektiven Untersuchung wurde an 44 Patienten (33 Männer, 11 Frauen) riach einer elektiven orthotopen Lebertransplantation die Duplexsonographie 196ma1 angewendet. Ziel der Untersuchung war es festzustellen, inwieweit and in welchem zeitlichen Zusammenhang sich die Parameter pulsatiler FluBindex (PFI) und Dämpfungsindex (DI) bei Komplikationen wie Abstoung und Cholangitis verändern. Der Duplex-Doppler-Ultraschall wurde im Mittel 5mal pro Patient durchgeführt. Die letzte Sonographie erfolgte am Entlassungstag. Bei den Messungen fiber der Leberarterie, der Pfortader und den Lebervenen wurden jeweils der PFI und der DI bestimmt. Die Ergebnisse der Indexuntersuchungen wurden mit dem klinischen Verlauf (Abstoung, Cholangitis) sowie mit den Resultaten von 88 Biopsiepräparaten der Lebertransplantate in Beziehung gesetzt. Bezüglich einer histologisch gesicherten AbstoBung ergab der PFI (über der Leberarterie gemessen) eine Sensitivität von 69,4 % and eine Spezifitdt von 72,2 %, der DI (über den Lebervenen gemessen) eine Sensitivität von 89,4% und eine Spezifitdt von 89,1 %. Wenn auch die einfach und beliebig oft anwendbare Untersuchungstechnik die bioptische Sicherung einer Rejektion nicht ersetzen kann, so ist sie in hohem Mae in der Lage, Indikationen zur Biopsie frühzeitig stellen zu lassen und ein Ansprechen auf eine Therapie kurzfristig und mit holier Genauigkeit anzuzeigen.
Duplex sonography after orthotopic liver transplantation: findings in 44 patients
In a prospective study, 44 patients (11 women, 33 men) who had received orthotopic liver transplants underwent a total of 196 consecutive duplex Doppler ultrasound examinations. The aim of the study was to evaluate the correlation between the pulsatile flow index (PFI) and the damping index (DI) as far as complications as rejection or cholangitis were concerned. The patients were examined five times each on average. The PFI and DI were measured in the hepatic artery, the portal vein and the hepatic veins. The findings were compared with the clinical course (cholangitis, rejection) and the histomorphological diagnosis as determined in biopsy specimens. In biopsy-proven rejection episodes, the sensitivity of the PFI in the hepatic artery was 69.4%, the specificity 72.2%. The sensitivity of the DI in the hepatic vein was 89.4%, the specificity 89.1 %. Combining the two, specificity was more than 90%. PFI and DI in the portal vein bore no apparent relation to clinical course or histomorphological diagnosis. We found duplex Doppler ultrasound extremely beneficial in determining the timing and indication for liver biopsy. In addition, this simple examination, which can be performed as often as desired, accurately shows the transplanted liver's response to measures taken to counter rejection.
  相似文献   
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73.
BACKGROUND: Chronic venous access devices (CVADs), placed for phlebotomy and the administration of medications and nutrition, require fluoroscopy to confirm correct catheter position. Long-term central venous catheters placed using an electromagnetic catheter locating system (EMCLS) could result in decreased radiation exposure and decreased cost without compromising accuracy of position. METHODS: Charts of patients who underwent placement of CVADs at University of New Mexico (UNM) Hospital or UNM Cancer Center were reviewed. Inclusion criteria included age >20 years and placement of a central CVAD utilizing fluoroscopy (group 1) or the EMCLS (group 2). Radiation exposure, complications, cost, and accuracy of placement were determined for each technique. RESULTS: Between June 1996 and June 1998, 196 patients underwent placement of CVADs. Complete data sets were available for 46 patients in each group. There were no statistically significant differences in age, gender, complications, or operating room times (P = 0.26). Fluoroscopy and EMCLS were equally accurate for the correct placement of the tip of the line (P = 0.12). Mean patient radiation exposure was EMCLS, 30 mRem, and fluoroscopy, 771 mRem. EMCLS significantly decreased cost (P = 0.025) when compared with fluoroscopic assisted catheter placement. CONCLUSIONS: The use of EMCLS for CVAD placement reduces radiation exposure and cost without compromising the accuracy of placement when compared with standard fluoroscopic-assisted placement.  相似文献   
74.
Rats were treated with a hepatotoxin thioacetamide (TAA) and examined 21 days later, when they showed moderate fatty metamorphosis of the liver and morphological changes in brain indicative of excitotoxic neuronal damage, but no evident biochemical or neurophysiological symptoms of hepatic encephalopathy (HE). High-performance liquid chromatography (HPLC) analysis of extracellular amino acids in striatal microdialysates of TAA-treated rats revealed a significant increase in the excitatory amino acids glutamate (Glu) and aspartate (Asp) and their amino acid metabolites glutamine (Gln) and alanine (Ala). Microdialysis in the presence of 50 mM K+ triggered in TAA-treated rats an accumulation of Asp and Glu, and diminished the accumulation of Gln. These effects were virtually absent in control rats. None of the treatments affected the accumulation of the nontransmitter amino acid leucine (Leu). The above changes mirror those previously described in symptomatic HE and are likely to contribute to excitotoxic damage. The basal microdialysate content of taurine (Tau), an amino acid with antioxidant and volume regulatory properties, was 60% lower in TAA-treated rats than in control rats despite its increased blood-to-brain transport. The decrease in extracellular Tau may thus reflect Tau redistribution to adjacent central nervous system (CNS) cells manifesting a cell-protective response. Stimulation with 50 mM K+ increased extracellular Tau in control rats by 182% and in TAA-treated rats by 322%. Stimulation with 100 microM N-methyl-D-aspartate (NMDA) increased extracellular Tau in control rats by 27 % and in TAA-treated rats by as much as 250%. The increase of K+- or NMDA-dependent Tau release may reflect improved cell volume regulation and neuroprotection and contribute to attenuation of neurologic symptoms in rats with liver failure.  相似文献   
75.
Lid-loading with precious metals, described by Illig in 1958, has become increasingly important. Because of its good functional and cosmetic results this method is superior to tarsorrhaphy. Furthermore, lid-loading can be combined with additional surgical techniques to achieve more dynamic lid-closure. In a prospective study we examined the results after lid-loading and discuss postoperative changes of the cornea.  相似文献   
76.
In the electrofluorescence method, a solution of DNA with covalentlybound polycyclic hydrocarbons is placed in an electric field,and changes in the intensity of polarized fluorescence are observed.Under the correct conditions, these changes can be used to determinea value for the angle between the long axis of the hydrocarbonmolecule and the axis of the DNA helix. For DNA or poly(dA-dT)treated with each stereoisomer of anti-benzo[c]phenanthrenediolepoxide, ranged from 55° to 61°, consistent witha mixture of quasi-intercalated adenine adducts and externallybound guanine adducts. Similar results were obtained with anotherset of ‘fjord-region’ diolepoxides, derived frombenzo[c]chrysene. Adducts in DNA treated with diolepoxides derivedfrom chrysene, 5-methylchrysene or 6-methylchrysene gave of53°, so the predominant adducts are externally bound, probablyin the minor groove of DNA.  相似文献   
77.
Large-scale communication campaigns for health promotion and disease prevention involve analysis of audience demographic and psychographic factors for effective message targeting. A variety of segmentation modeling techniques, including tree-based methods such as Chi-squared Automatic Interaction Detection and logistic regression, are used to identify meaningful target groups within a large sample or population (N = 750-1,000+). Such groups are based on statistically significant combinations of factors (e.g., gender, marital status, and personality predispositions). The identification of groups or clusters facilitates message design in order to address the particular needs, attention patterns, and concerns of audience members within each group. We review current segmentation techniques, their contributions to conceptual development, and cost-effective decision making. Examples from a major study in which these strategies were used are provided from the Texas Women, Infants and Children Program's Comprehensive Social Marketing Program.  相似文献   
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79.
Summary In 12 three-months-old pigs a window-shaped tracheal defect was made and the defect closed by a precisely fitting Cialit-fixed, human tracheal heterograft. The macroscopic, microscopic, scanning and transmission electron microscopic investigation of the grafted area revealed that the tracheal epithelium was formed by microvillous epithelial cells primarily. 3 months after grafting cartilage of the tracheal transplant survived but after 9 months was replaced by a tight scar. The connective tissue plate thus formed was sufficiently stable to maintain normal respiration in the pigs.This work was supported by the Fonds zur Förderung der wissenschaftlichen Forschung (Project no. 3494)The authors thank A. Laminger and G. Sulzer for photographic work  相似文献   
80.
Cowden syndrome and Lhermitte-Duclos disease.   总被引:7,自引:0,他引:7  
S Albrecht  R M Haber  J C Goodman  M Duvic 《Cancer》1992,70(4):869-876
BACKGROUND. Cowden syndrome (CS) is a rare but underdiagnosed autosomal dominant condition also known as "multiple hamartoma-neoplasia syndrome." Patients have multiple tricholemmomas (a type of benign skin appendage tumor) and oral papillomatosis and cutaneous keratoses. They often have goiter, gastrointestinal polyps, and hamartomatous soft tissue lesions. Breast cancer affects approximately one third of women with CS. Lhermitte-Duclos disease (LDD) is a peculiar proliferation of abnormal neuronal elements of the cerebellum that has features of a hamartoma and of a neoplasm. METHODS. The authors described two patients who have both CS and LDD. Also reviewed were 50 of approximately 62 previously described cases of LDD (identified through literature searches) in an effort to find patients with LDD who had other associated lesions. RESULTS. Only one other patient in whom both LDD and CS were recognized has been reported. In addition, a number of patients with LDD who had other neoplasms and/or thyroid lesions have been described. CONCLUSIONS. Given the rarity of these two entities, we believe that their association is not fortuitous. LDD fits into the concept of CS as a hamartoma-neoplasia syndrome. In addition, a number of patients with LDD who had other neoplasms or thyroid lesions have been reported, raising the possibility that CS and LDD are more closely linked than is generally appreciated. We suspect that there are more patients with LDD who have unrecognized CS. Patients with either of the two diseases should be examined and followed up for evidence of the other.  相似文献   
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