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41.
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   
42.
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   
43.
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   
44.
45.
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   
46.
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   
47.

Hintergrund  

Cherubismus ist eine seltene genetisch bedingte Erkrankung der Knochen, die fast ausschlie?lich den Ober- und Unterkiefer betrifft.  相似文献   
48.
The involvement of glutamate mediated neurotoxicity in the pathogenesis of Alzheimer's disease is finding increasingly more acceptance in the scientific community. Central to this hypothesis is the assumption that in particular glutamate receptors of the N-methyl-D-aspartate (NMDA) type are overactivated in a tonic rather than a phasic manner. Such continuous mild activation leads under chronic conditions to neuronal damage. Moreover, one should consider that impairment of plasticity (learning) may result not only from neuronal damage per se but also from continuous activation of NMDA receptors. To investigate this possibility we tested whether overactivation of NMDA receptors using either non-toxic doses/concentrations of a direct NMDA agonist or through an indirect approach--decrease in magnesium concentration--produces deficits in plasticity. In fact NMDA both in vivo (passive avoidance test) and in vitro (LTP in CA1 region) impaired learning and synaptic plasticity. Under these conditions memantine which is an uncompetitive NMDA receptor antagonist with features of "improved magnesium" (voltage dependence, affinity) attenuated the deficit. The more direct proof that memantine can act as a surrogate for magnesium was obtained in LTP experiments under low magnesium conditions. In this case as well, impaired LTP was restored in the presence of therapeutically relevant concentrations of memantine (1 microM). In vivo, doses leading to similar brain/serum levels produce neuroprotection in animal models relevant for neurodegeneration in Alzheimer's disease such as neurotoxicity produced by inflammation in the NBM or beta-amyloid injection to the hippocampus. Hence, we postulate that if in Alzheimer's disease overactivation of NMDA receptors occurs indeed, memantine would be expected to improve both symptoms (cognition) and slow down disease progression because it takes over the physiological function of magnesium.  相似文献   
49.
Amputation of the lower leg is not uncommon in elderly patients with chronic infections or vascular problems of the leg and foot, and most often it is performed below the knee or on the distal part of the lower leg (i.e., Syme's amputation). After operation, healing disorders with or without infection can occur, and usually structural imaging methods are performed for diagnosis. Radionuclide imaging using a combination of bone scans and infection scintigraphy can help to identify bone and soft tissue infection. Interpreting radionuclide scans is difficult, because imaging findings after amputation may depend not only on the level of resection and the disease investigated but also on the time that has elapsed since surgery. Typical imaging patterns of bone or infection scintigraphy of five patients are described  相似文献   
50.
Sutherlandia frutescens (tribe Galegeae, Fabaceae), a popular plant in traditional medicine, is indigenous to South Africa, Lesotho, southern Namibia and southeastern Botswana. It is chemically, genetically and geographically extremely variable and has been divided into three subspecies and several regional forms. A second species, Sutherlandia tomentosa, is localized along the Cape coast. Sutherlandia is sometimes treated as part of the genus Lessertia. There are numerous vernacular names and a wide diversity of uses, including poor appetite, indigestion, stomach complaints, dysentery, colds, influenza, kidney conditions, fever, diabetes, internal cancers, uterine troubles, liver conditions, backache, rheumatoid arthritis, urinary tract infections, stress and anxiety, dropsy and heart failure. Notable is the use as a bitter tonic ("blood purifier"), anti-stress medication ('musa-pelo) and, at least since 1895, specifically as a cancer tonic (both as treatment and as prophylaxis). Externally it is applied to haemorrhoids, inflamed wounds and eye infections. Recent in vitro and in vivo studies have shown antiproliferative, anti-HIV, anti-diabetic, anti-inflammatory, analgesic, antibacterial, anti-stress, anticonvulsant and antithrombotic activities. Aqueous extracts often differ in activity from organic solvent extracts. The presence of high levels of free amino acids, non-protein amino acids such as canavanine and GABA, the cyclitol pinitol, flavonols and triterpenes (including SU1, a cycloartane-type triterpene saponin) provide plausible hypotheses on how these compounds, individually or collectively, may be responsible for the reputed efficacy in a wide range of ailments. Results of animal studies, as well as a phase I clinical study, have shown no indications of toxicity. Sufficient preclinical data are now available to justify controlled clinical studies.  相似文献   
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