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51.
S Hatakeyama A Hamasaki I Negishi DY Loh F Sendo K Nakayama K Nakayama 《Canadian Metallurgical Quarterly》1998,10(5):631-637
Atrial reentrant tachycardia (ART) was ablated in an anatomically guided approach. Five patients with ART underwent 2 linear incisions without careful pace or activation mapping. One line was from an atrial activation site earlier than P wave onset to the nearest fixed anatomic conduction barrier, i.e., the inferior vena cava or coronary sinus ostium. The other line was made just above or closely crossed the first line vertically. Mean application time was 29 +/- 19 minutes, and the application energy was 14,001 +/- 12,322 joules. Mean follow-up after ablation was 15 +/- 10 months. Three patients underwent electrophysiologic study three months after and sustained ART was not induced. All patients were free of sustained tachycardia events without antiarrhythmic drugs during the postoperative clinical course. Although anatomically guided ablation for ART requires much time and energy, it is easily and effectively done without careful activation or pace mapping, and is indicated if ablation using activation mapping or entrainment technique fails to cure the ART. 相似文献
52.
HM El-Zimaity H Ota S Scott DE Killen DY Graham 《Canadian Metallurgical Quarterly》1998,122(8):732-736
OBJECTIVE: To develop an inexpensive stain to simultaneously visualize gastric morphology and Helicobacter pylori. METHODS: Gastric biopsies were stained with Genta stain using manual methods, and with carbol fuchsin/Alcian blue/hematoxylin-eosin using an automatic slide stainer (Sakura DRS-601). Slides were then coded and interpreted by 2 pathologists. Helicobacter pylori was scored using a visual scale (0 [none] to 5 [maximum]). RESULTS: One hundred slides were scored; H pylori was present in 64%. Carbol fuchsin/Alcian blue/hematoxylin-eosin stain gave excellent demonstration of gastric morphology. All positive cases (score > or =2) were correctly interpreted. Thirty-six slides had a score of 1 (< or =2 bacteria per entire slide). Of these, 10 were scored negative by Genta stain and 12 were scored negative by the carbol fuchsin/Alcian blue/hematoxylin-eosin stain (P = not significant). Hematoxylin-eosin was significantly less accurate than either of the other 2 stains (P < .02). CONCLUSION: The carbol fuchsin/Alcian blue/hematoxylin-eosin (El-Zimaity) stain is an economical stain suitable for simultaneous visualization of H pylori infection and gastric morphology. 相似文献
53.
Positron Emission Tomography of bromine-76 and yttrium-86 results in the detection of coincident events that are not strictly associated with annihilation photon pairs. Instead, these coincidences occur because prompt gamma rays emitted by these nuclides result in cascades of photons that are emitted within the timing window of the PET scanner. Pairs of detected photons from these cascades are not angularly correlated and therefore contain little information regarding the location of their source. Furthermore, these coincidences are not removed by correction procedures (e.g., randoms, scatter) routinely applied to PET data. If left uncorrected, the cascade coincidences will result in spurious apparent activity within the PET images. A correction, applied within projection space, that removes the cascade coincidence signal from septa-in (i.e., two-dimensional) datasets is proposed and tested on phantom data. 相似文献
54.
The aims of this investigation were to determine whether viable cultures of lactic acid-producing organisms (LAB) can bind dietary carcinogens and to assess the consequences of binding for the absorption from the gut, distribution in the body and in vivo genotoxicity of ingested carcinogens. The carcinogens used in this study were ones known to be present in the human diet, namely benzo[a]pyrene (B(a)P, aflatoxin B1 (AFB1) and the cooked food carcinogens 2-amino-3-methyl-3H-imidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 5-phenyl-2-amino-1-methylimidazo [4,5-f]pyridine (PhIP) and 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2). They represent a range of structural types so that the specificity of any binding effects could be addressed. Of the carcinogens tested, B(a)P and Trp-P-2 were bound most effectively by the two LAB strains Bifidobacterium longum and Lactobacillus acidophilus. AFB1 was poorly bound, while MeIQx, MeIQ, PhIP and IQ were bound to an intermediate degree. The extent of the binding of the heterocyclic amine carcinogens was dependent on the pH conditions during incubation and this effect was more apparent with B. longum than with L. acidophilus. Using the host-mediated assay (HMA), an in vivo bacterial mutation assay, it was demonstrated that the administration of bacterial cell suspensions of B. longum and L. acidophilus did not lead to a reduction in induced mutagenicity by MeIQ, MeIQx or Trp-P-2, detectable in the liver of treated mice compared with controls. The lack of a protective effect could not be attributed to a short period of contact between bacterial cells and mutagens, since similar results were obtained after preincubating bacteria and mutagens together at pH 5 for 50-60 min, to maximize the binding, before gavaging the mice. Lack of activity of B(a)P in the HMA prevented the determination of the effect of LAB on genotoxicity of the polycyclic aromatic hydrocarbon. However, it is clear from the radiolabel distribution study that the amount of the carcinogen entering the blood was not significantly reduced by B. longum administration. In addition, the amount of radiolabelled B(a)P that reached the target organs (liver, lungs and heart) was also not affected by the LAB administration. A similar lack of inhibitory effect of B. longum on blood concentration and accumulation in the liver of Trp-P-2 was apparent. The results of the present study suggest that although LAB may bind carcinogens in vitro, this does not lead to major changes in absorption and distribution of carcinogens in the body, or in their genotoxic activity in the liver. 相似文献
55.
The in vitro activity of cefepime was compared to that of ceftazidime, ceftriaxone, and cefotaxime in a multicenter study involving 10 clinical microbiology laboratories and clinical isolates from 18 Brazilian hospitals from 7 cities (4 states). A total of 982 isolates consecutively collected between December 1995 and March 1996 were susceptibility tested by using Etest and following the NCCLS procedures for agar diffusion tests. The cefepime spectrum was broader than that of the other broad-spectrum cephalosporins against both Gram-negative rods and Gram-positive cocci. Cefepime was particularly more active against Enterobacter sp. (MIC90, 2 micrograms/ml), Serratia sp. (MIC90, 2 micrograms/ml) and oxacillin-susceptible Staphylococcus aureus (MIC90, 3 micrograms/ml). Against Pseudomonas aeruginosa, cefepime (MIC90, 16 micrograms/ml) was slightly more active than ceftazidime (MIC90, 32 micrograms/ml) and 8- to 16-fold more active than ceftriaxone of cefotaxime (MIC90, > 256 micrograms/ml). Our results show that nosocomial bacteria, especially Gram-negative rods, have a high rate of cephalosporin resistance in Brazil. However, part of these resistant bacteria remains susceptible to cefepime. The Etest was shown to be an excellent method for multicenter studies of the in vitro evaluation of new antimicrobial agents. 相似文献
56.
ET Creagan KM Rowland VJ Suman CG Kardinal RF Marschke RS Marks WJ Maples 《Canadian Metallurgical Quarterly》1997,20(5):490-492
Adoptive immunotherapy (AI) with interleukin-2 (IL-2) and lymphokine-activated killer cells (LAK) is an antineoplastic modality in which immune-activated cells are administered to a host with advanced cancer in an attempt to mediate tumor regression. Levamisole (LEV), an immune stimulant, has been suggested to have therapeutic effectiveness in a variety of cancers. After a phase I trial of recombinant IL-2 plus LEV, a phase II trial of this combination was conducted in patients with advanced malignant melanoma. Nineteen patients were entered in the trial. They received IL-2 at 3 x 10(6) U/m2 subcutaneously daily x 5 plus LEV 50 mg/ m2 orally three times daily (p.o. t.i.d.) x 5. Patients were reevaluated at four-week intervals. None of the patients achieved a partial or complete regression (PR, CR). The median time to treatment failure (refusal, progression, or off study due to toxicity) was 56 days. Grade IV toxicities included vomiting (3 patients), lethargy (1 patient), and musculoskellar pain (1 patient). This regimen is not recommended for further testing in patients with advanced malignant melanoma. 相似文献
57.
58.
T Sakai MK Razavi CP Semba ST Kee DY Sze MD Dake 《Canadian Metallurgical Quarterly》1998,9(6):1025-1028
Lactic acidosis due to thiamine deficiency is known to complicate chemotherapy and radiotherapy treatment of malignant extracranial tumors, but to the authors' knowledge, this complication has not been reported in patients treated for malignant brain tumors. They report three such cases, demonstrating that this complication can occur during treatment of brain tumors. In all patients, consciousness levels deteriorated within 1 to 2 days. Serum lactic acid levels increased to concentrations between 62 and 96.7 mg/dl, resulting in severe metabolic acidosis. A low blood thiamine level (9 ng/ml) was demonstrated at the onset in one case, and high-dose thiamine infusions dramatically improved lactic acidemia as well as impairment of consciousness in two cases. In the other case, hydrocephalus was suspected initially, resulting in a delay in thiamine supplementation. Clinical differentiation of this form of lactic acidosis from hydrocephalus or tumor progression can be very difficult in a patient undergoing treatment for a malignant brain tumor. Demand for thiamine is thought to be increased in patients with malignant brain tumors, and supplemental thiamine during treatment is necessary to prevent lactic acidosis. When this complication occurs, immediate treatment with sufficient thiamine is essential, together with normalization of pH by using sodium bicarbonate. With timely intervention, the level of consciousness can recover to the preacidotic state with no new neurological deficits. 相似文献
59.
SF Keevil B Barbiroli JC Brooks EB Cady R Canese P Carlier DJ Collins P Gilligan G Gobbi J Hennig H Kügel MO Leach D Metzler V Mlynárik E Moser MC Newbold GS Payne P Ring JN Roberts IJ Rowland T Thiel I Tkác S Topp HJ Wittsack F Podo 《Canadian Metallurgical Quarterly》1998,16(9):1093-1106
We have performed a multicentre trial to assess the performance of three techniques for absolute quantification of cerebral metabolites using in vivo proton nuclear magnetic resonance (NMR). The techniques included were 1) an internal water standard method, 2) an external standard method based on phantom replacement, and 3) a more sophisticated method incorporating elements of both the internal and external standard approaches, together with compartmental analysis of brain water. Only the internal water standard technique could be readily implemented at all participating sites and gave acceptable precision and interlaboratory reproducibility. This method was insensitive to many of the experimental factors affecting the performance of the alternative techniques, including effects related to loading, standing waves and B1 inhomogeneities; and practical issues of phantom positioning, user expertise and examination duration. However, the internal water standard method assumes a value for the concentration of NMR-visible water within the spectroscopic volume of interest. In general, it is necessary to modify this assumed concentration on the basis of the grey matter, white matter and cerebrospinal fluid (CSF) content of the volume, and the NMR-visible water content of the grey and white matter fractions. Combining data from 11 sites, the concentrations of the principal NMR-visible metabolites in the brains of healthy subjects (age range 20-35 years) determined using the internal water standard method were (mean+/-SD): [NAA]=10.0+/-3.4 mM (n=53), [tCho]=1.9+/-1.0 mM (n=51), [Cr + PCr]=6.5+/-3.7 mM (n=51). Evidence of system instability and other sources of error at some participating sites reinforces the need for rigorous quality assurance in quantitative spectroscopy. 相似文献
60.
M Dominguez K Dejgaard J Füllekrug S Dahan A Fazel JP Paccaud DY Thomas JJ Bergeron T Nilsson 《Canadian Metallurgical Quarterly》1998,140(4):751-765
Abstract. Five mammalian members of the gp25L/ emp24/p24 family have been identified as major constituents of the cis-Golgi network of rat liver and HeLa cells. Two of these were also found in membranes of higher density (corresponding to the ER), and this correlated with their ability to bind COP I in vitro. This binding was mediated by a K(X)KXX-like retrieval motif present in the cytoplasmic domain of these two members. A second motif, double phenylalanine (FF), present in the cytoplasmic domain of all five members, was shown to participate in the binding of Sec23 (COP II). This motif is part of a larger one, similar to the F/YXXXXF/Y strong endocytosis and putative AP2 binding motif. In vivo mutational analysis confirmed the roles of both motifs so that when COP I binding was expected to be impaired, cell surface expression was observed, whereas mutation of the Sec23 binding motif resulted in a redistribution to the ER. Surprisingly, upon expression of mutated members, steady-state distribution of unmutated ones shifted as well, presumably as a consequence of their observed oligomeric properties. 相似文献