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81.
Sanjuàn A Vidal-Sicart S Zanón G Pahisa J Velasco M Fernández PL Santamaría G Farrús B Muñoz M Albanell J Pons F Vanrell JA 《European journal of nuclear medicine and molecular imaging》2005,32(8):932-936
Purpose The aim of this study was to evaluate the frequency of false-negative (FN) sentinel node procedures in patients with breast cancer and the subsequent clinical outcome in such patients.Methods A total of 325 breast cancer patients underwent sentinel lymph node biopsy at our institution between June 1998 and May 2004. A 2-day protocol was used to localise the sentinel node with the injection of 99mTc-nanocolloid. There were two phases in the study: the learning phase (105 patients) and the application phase (220 patients). In the learning phase, a complete lymphadenectomy was always performed. In the application phase, sentinel nodes were studied intraoperatively and lymphadenectomy was performed when considered warranted by the pathological intraoperative results.Results The median follow-up duration in the 220 patients studied during the application phase was 21.2 months (range 4–45 months). In this phase a total of 427 sentinel nodes were obtained (range 1–5 per patient, median 1.99), with 66 positive sentinel nodes in 56 patients (26%). The lymphadenectomies performed were also positive in 25% of cases (14 patients). We observed a total of two false-negative sentinel lymph node results (3.45%). One of them was found during the surgical excision of non-sentinel nodes, and the other presented as an axillary recurrence 17 months postoperatively (1.72% clinical false-negative rate). The latter patient died 1 year after the first recurrence.Conclusion After a median follow-up of 21.2 months we observed only one clinical recurrence among 220 patients. Our results indicate that adequate local control is achieved by application of the sentinel node protocol. 相似文献
82.
Labeling of epsilon-lysine crosslinking sites in proteins with peptide substrates of factor XIIIa and transglutaminase. 总被引:1,自引:2,他引:1 下载免费PDF全文
K N Parameswaran P T Velasco J Wilson L Lorand 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(21):8472-8475
Peptides patterned on the N-terminal sequence of fibronectin were synthesized and tested for amine acceptor qualities in reactions with dansylcadaverine catalyzed either by coagulation factor XIIIa or intracellular transglutaminase (protein-glutamine:amine gamma-glutamyltransferase, EC 2.3.2.13). On the basis of inverse half-saturations of the enzymes, the order of acceptor substrate affinity for factor XIIIa was pEAQQIV much greater than Boc-AQQIV greater than Boc-QQIV, and for transglutaminase, Boc-QQIV greater than Boc-AQQIV greater than pEAQQIV (amino acid residues are shown in one-letter code; pE, pyroglutamic acid; Boc, tert-butyloxycarbonyl). Sequence analysis of dansylcadaverine-substituted pEAQQIV indicated that the first of the two adjacent glutamine residues was the target of enzymatic modification. Boc-QIV showed no substrate activity with either enzyme. Crosslinking of crystallins in Ca2(+)-treated rabbit lens homogenate was readily inhibited by Boc-QQIV, Boc-AQQIV, and pEAQQIV, as was the formation of alpha-chain polymers in human fibrin by pEAQQIV in the presence of human factor XIIIa. SDS/PAGE analysis suggested that the inhibitory peptides selectively blocked the electron donor functionalities in these enzymatic crosslinking reactions. 相似文献
83.
Velasco JM Yoon IK Mason CJ Jarman RG Bodhidatta L Klungthong C Silapong S Valderama MT Wongstitwilairoong T Torres AG De Cecchis DP Pavlin JA 《Military medicine》2011,176(10):1096-1100
Laboratory-based surveillance for diarrheal and respiratory illness was conducted at the 2009 Republic of the Philippines-United States Balikatan exercise to determine the presence of specific pathogens endemic in the locations where the military exercises were conducted. Ten stool and 6 respiratory specimens were obtained from individuals meeting case definitions for diarrhea or respiratory illness. Stool specimens were frozen in dry ice and remotely tested using enzyme-linked immunosorbent assay for Rotavirus, Astrovirus, Adenovirus, Entamoeba histolytica, Giardia, and Cryptosporidium and polymerase chain reaction for enterotoxigenic Escherichia coli, Campylobacter, Shigella, Vibrio, Salmonella, and Norovirus. Eight (4 for Campylobacter jejuni, 2 for Campylobacter coli, 1 for Norovirus genogroup II, and 1 for both Campylobacter coli and enterotoxigenic Escherichia coli) of 10 samples were positive for at least 1 enteric pathogen. MassTag polymerase chain reaction for influenza A and B, respiratory syncytial virus groups A and B, human coronavirus-229E and human coronavirus-OC43, human metapneumovirus, enterovirus, human parainfluenza viruses 2,3, and 4a, human adenovirus, Haemophilus influenzae, Neisseria meningitidis, Streptococcus pneumoniae, Legionella pneumonia, and Mycoplasma pneumonia was done on respiratory specimens. Out of 6 samples, 3 tested positive for H. influenzae; 1 tested positive for both H. influenzae and human parainfluenza virus 3; and 2 tested negative. Laboratory-based surveillance can be useful in determining etiologies of diarrheal and respiratory illness of deployed military personnel. 相似文献
84.
Stirrup Jim Velasco Alejandro Hage Fadi G. Reyes Eliana 《Journal of nuclear cardiology》2017,24(3):1046-1053
Journal of Nuclear Cardiology - In 2014, the Task Force on Myocardial Revascularization of the European Society of Cardiology and the European Association for Cardio-Thoracic Surgery with the... 相似文献
85.
Velasco Stéphane Burg Samuel Delwail Vincent Guilhot Joelle Perdrisot Remy Guilhot Gaudeffroy Francois Tasu Jean-Pierre 《European journal of radiology》2013
Objective
To evaluate the clinical impact of diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) in staging of malignant lymphoma.Methods
Twenty-three patients with proven malignant lymphomas were prospectively enrolled. DWIBS (b = 0, 1000 s/mm2) examinations and PET-CT were performed respectively on an Intera 1.5 T unit and a Gyroscan PET-CT scan (Philips Medical system, Best, the Netherland). The criteria for positive node involvement were a size over 10 mm or an apparent diffusion coefficient (ADC) value under 0.75 10−3 mm2/s for nodes under 10 mm. For extranodal analysis, a high or heterogeneous signal on DWIBS was considered as positive. In cases of discordance, the reference standard for each region or organ was established at 6 months after the diagnosis according to all available clinical, biological information, as well as histological evidence or follow-up to prove or disprove the presence of disease.Results
DWIBS and PET-CT results were congruent in 333 node regions on the 345 areas analyzed, with excellent agreement (κ = 0.97, P < 0.0001). From 433 organs analyzed (one patient had splenectomy) extranodal disease was detected in 22 organs on DWIBS. The two imaging techniques agreed on 430 organs (κ = 0.99, P < 0.0001). Finally, Ann Arbor stages based on DWIBS and those of PET/CT were in agreement for 23 patients.Conclusions
For malignant lymphoma in a pre-therapeutic context, agreement between diffusion-weighted whole-body imaging and PET/CT is high for Ann Arbor staging. 相似文献86.
Xavier Bargalló Gorane Santamaría Montse del Amo Pedro Arguis José Ríos Jaume Grau Marta Burrel Enrique Cores Martín Velasco 《European journal of radiology》2014
Objectives
To assess the impact of shifting from a standard double reading plus arbitration protocol to a single reading by experienced radiologists assisted by computer-aided detection (CAD) in a breast cancer screening program.Methods
This was a prospective study approved by the ethics committee. Data from 21,321 consecutive screening mammograms in incident rounds (2010–2012) were read following a single reading plus CAD protocol and compared with data from 47,462 consecutive screening mammograms in incident rounds (2004–2010) that were interpreted following a double reading plus arbitration protocol. For the single reading, radiologists were selected on the basis of the appraisement of their previous performance.Results
Period 2010–2012 vs. period 2004–2010: Cancer detection rate (CDR): 6.1‰ (95% confidence interval: 5.1–7.2) vs. 5.25‰; Recall rate (RR): 7.02% (95% confidence interval: 6.7–7.4) vs. 7.24% (selected readers before arbitration) and vs. 3.94 (all readers after arbitration); Predictive positive value of recall: 8.69% vs. 13.32%. Average size of invasive cancers: 14.6 ± 9.5 mm vs. 14.3 ± 9.5 mm. Stage: 0 (22.3/26.1%); I (59.2/50.8%); II (19.2/17.1%); III (3.1/3.3%); IV (0/1.9%). Specialized breast radiologists performed better than general radiologists.Conclusions
The cancer detection rate of the screening program improved using a single reading protocol by experienced radiologists assisted by CAD, at the cost of a moderate increase of the recall rate mainly related to the lack of arbitration. 相似文献87.
Paniagua-Pérez R Madrigal-Bujaidar E Reyes CS Pérez GJ Velasco MO Molina D 《Toxicology letters》2002,132(2):123-129
Imipramine and desipramine are two widely used tricyclic antidepressants which have shown conflicting results in regard to their in vitro genotoxic evaluation. The aim of this investigation was to determine the capacity of these compounds to induce in vivo sister-chromatid exchanges (SCEs) in mouse bone marrow cells. For each compound, the animals were organized in five groups constituted by five individuals. They were intraperitoneally (ip) administered with the test substances as follows: a negative control group treated with 0.4 ml of distilled water, a positive control group administered with cyclophosphamide (70 mg/kg), three groups treated with imipramine (7, 20 and 60 mg/kg), and three other groups treated with desipramine (2, 20 and 60 mg/kg). The general procedure included the subcutaneous implantation to each mouse of a 5-bromodesoxyuridine tablet (45 mg), and 1 h later, the administration of the chemicals involved. Twenty-one hours after the tablet implantation, the mice received colchicine, and 3 h later their femoral bone marrow was obtained in KCL, fixed, and stained with the Hoechst-Giemsa method. The results showed that both compounds were SCE inducers, starting from the second tested dose. The response of these compounds was dose-dependent, and showed that the highest tested dose increased about four times the SCE control level. The cellular proliferation kinetics was not affected by the chemicals, and the mitotic indexes were slightly diminished with the highest dose. These results indicate an in vivo genotoxic potential for both chemicals, and suggest that it is pertinent to follow their evaluation in other models. 相似文献
88.
89.
Morán JM Salas J Sanjuán S González G Gallello A Serrano A Vinagre Velasco LM 《Cirugía pediátrica : organo oficial de la Sociedad Espa?ola de Cirugía Pediátrica》2002,15(4):168-171
We present a case left paramesocolic hernia and review the literature. The patients was a 14 years old male and had suffered periods of relapses into abdominal pain from the age of three. When for years old he was operated on using the Nisses technique. Also a laparoscopy had already been performed on this same patient when he was 13 years old, without discovering any pathological conditions. In a new upper gastrointestinal serie, realized one year later, a retroperitoneal incarceration and a paraduodenal loop of jejunum was observed, which obstructed, partially the second part of the duodenum. We have not found the anatomical characteristics of this case in any previous report. In the ample literature pressured, it was confirmed that almost all the clinical cases, previously published had suffered a relapse abdominal pain crisis, diagnosed in advanced states and in/or emergency situations. This produces a mortality rate higher than 20% and or irreparable digestive damage. In cases involving paraduodenal hernias, there exists a low rate of diagnostic suspicion. These delays and diagnostic errors cause irreparable damage. In those patients who suffer relapses into abdominal pain syndrome, one should always include the differential diagnosis of PMH, applying a complete gastrointestinal serie or a CT-Scan with contrast. 相似文献
90.
Regulation by nitric oxide of endotoxin-induced tissue factor and plasminogen activator inhibitor-1 in endothelial cells 总被引:5,自引:0,他引:5
Pérez-Ruiz A Montes R Velasco F López-Pedrera C Antonio Páramo J Orbe J Hermida J Rocha E 《Thrombosis and haemostasis》2002,88(6):1060-1065
The increase in nitric oxide (NO) production in lipopolysaccharide (LPS)-induced sepsis is thought to contribute to the development of shock. However, NO could also play an antithrombotic role. Little is known about the modulating effect of NO on the endothelial overexpression and production of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1) occurring in endotoxemia. We analyzed the effect of N(G)-nitro-L-arginine-methyl-ester (L-NAME), an inhibitor of NO synthases, and S-nitroso-N-acetyl-D,L-penicillamine (SNAP), a NO donor, on the expression and synthesis of TF and PAI-1 by LPS-challenged human umbilical vein endothelial cells (HUVEC): L-NAME enhanced the increase in TF mRNA and antigen levels (P <0.05) observed in LPS-treated HUVEC; SNAP down-regulated the LPS-induced TF increment (p <0.05). However, no effects of NO on regulation of the LPS-dependent increase in PAI-1 could be seen. Thus, NO could play an antithrombotic role in sepsis by down-regulating the endothelial overexpression and production of TF. 相似文献