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61.
J. L. Quesada J. Lorente Pedro Quesada 《European archives of oto-rhino-laryngology》2000,257(7):386-388
Globus pharyngeus is a relatively common complaint in an ear, nose, and throat consulting room and may account for 3–4% of
outpatient referrals. The cause is still unknown, although a number of hypotheses have been suggested. Between 40% and 75%
of the patients remain symptomatic despite any treatment regimen. Thirteen patients from a group of 124 with the diagnosis
of globus pharyngeus and no response to medical treatment were treated with partial epiglottectomies. One year after the surgery
all but one patient were free of symptoms. Our experience indicates that partial epiglottectomy can be a good treatment for
those patients with globus pharyngeus in whom no cause is found after all studies are performed or when medical treatment
fails.
Received: 19 October 1999 / Accepted: 16 December 1999 相似文献
62.
Philip J. Bergman Karen R. Gravitt Nancy E. Ward Pedro Beltran Krishna P. Gupta Catherine A. O'Brian 《Investigational new drugs》1997,15(4):311-318
Phorbol ester protein kinase C (PKC) activators and PKC isozyme over-expression have been shown to significantly reduce intracellular accumulation of chemotherapeutic drugs, in association with the induction of multidrug resistance (MDR) in drug-sensitive cancer cells and enhancement of drug resistance in MDR cancer cells. These observations constitute solid evidence that PKC plays a significant role in the MDR phenotype of cancer cells. PKC-catalyzed phosphorylation of the drug-efflux pump P-glycoprotein was recently ruled out as a contributing factor in MDR. At present, the sole drug transport-related event that has been identified as a component of the role of PKC in MDR is PKC-induced expression of the P-glycoprotein-encoding gene mdr1. The objective of this study was to test the hypothesis that PKC can modulate the uptake of chemotherapeutic drugs in cancer cells independently of P-glycoprotein. We analyzed the effects of selective PKC activators/inhibitors on the uptake of radiolabelled cytotoxic drugs by cultured human colon cancer cells that lacked P-glycoprotein activity and did not express the drug efflux pump at the level of message (mdr1) or protein. We found that the selective PKC activator 12-O-tetradecanoylphorbol-13-acetate (TPA) significantly reduced uptake of [14C] Adriamycin and [3H] vincristine in human colon cancer cells devoid of P-glycoprotein activity, and that PKC-inhibitory N-myristoylated PKC- pseudosubstrate synthetic peptides potently and selectively induced uptake of the cytotoxic drugs in the phorbol ester-treated and non-treated colon cancer cells. TPA treatment of the cells did not induce expression of either P-glycoprotein or its message mdr1. In contrast with [14C]Adriamycin and [3H] vincristine uptake, [3H] 5-fluorouracil uptake by the cells was unaffected by TPA and reduced by the PKC-inhibitory peptides. These results indicate that PKC activation can significantly reduce the uptake of multiple cytotoxic drugs by cancer cells independently of P-glycoprotein, and that N-myristoylated PKC- pseudosubstrate peptides potently and selectively induce uptake of multiple cytotoxic drugs in cultured human colon cancer cells by a novel mechanism that does not involve P-glycoprotein and may involve PKC isozyme inhibition. Thus, N-myristoylated PKC- pseudosubstrate peptides may offer a basis for the development of agents that reverse intrinsic drug resistance in human colon cancer. 相似文献
63.
64.
Amelia Rodríguez Martín José Manuel Martínez Nieto Miguel Angel Ruiz Jiménez José Pedro Novalbos Ruiz M. Carmen Díaz Vázquez Yamin Chocrón Fernández Miguel Angel Rendón Gómez Carmen Cano Fernández 《European journal of epidemiology》1999,15(7):643-648
In recent years, eating disorders (Anorexia and Bulimia Nervosa) have increased and are appearing at increasingly younger ages. They affect predominantly adolescent females 12 to 25 years of age. The objective of this study of adolescents is to detect and discuss unhealthy eating behaviour, defined by either of two factors: (1) following a slimming diet not advised or supervised by any person trained in health care; or (2) eating very large quantities at irregular times, not related to anxiety or stress. A transversal study has been undertaken of 630 school children of 14–18 years of age (average: 15.9 years) in Cádiz (Andalucia, Spain), using an anonymous self-reporting questionnaire to collect data on personal and educational situation, on eating habits, on nutritive intake and knowledge of nutrition, and on dieting and physical exercise. The study has considered averages, ratios, statistical significance (x
2) and, as a measure of risk, the Disequality Ratio of Prevalence (DRP). Anomalous eating behaviour was detected in 46.3% (292), with females predominant by a ratio of 2:1. Comparing groups with anomalous and with normal eating habits, significant differences were detected in respect of: perception of body image (p<0.001), frequency of weighing oneself (p<0.05), periods of abstinence from eating (DRP 1.66; 95% confidence interval (CI): 1.66–2.37), provocation of vomiting (DRP 2.02; 95% CI: 1.13–3.65), use of laxatives (DRP 4.25; 95% CI: 1.08–9.63), and the exclusion of certain meals and types of food, mainly bread and cereals, fats and sugars. Conclusions are drawn on the substantial scale of unhealthy eating behaviour among adolescents in Cadiz. More adequate education on personal health and related social issues should be provided. 相似文献
65.
Professor Jose L. Balibrea M.D. Jose Gomez M.D. Jose R. Alemany M.D. Jose Aznar M.D. Mercedes Canela M.D. Enrique Castells M.D. Jose L. Fernandez M.D. Pedro G. Barreno M.D. Javier Ruiz M.D. 《World journal of surgery》1980,4(1):83-89
The purpose of these experiments was to study the incidence of stress ulcers in restrained rats and to correlate it with hypothalamic and adrenal cortical and medullary activity, with and without vagotomy. A total of 217 adult rats were used, grouped into 56 sets, and distributed at random in 5 experimental groups. Restraint was followed by a 79% incidence of ulceration in the glandular portion of the gastric mucosa. Vagotomy made these worse (p<0.01). Hypothalamic levels of catecholamines and serotonin showed no significant changes. Urinary measurements revealed decreased excretion of 17-ketosteroids (p<0.001), increased excretion of uropepsinogen (p<0.01), and no significant changes in vanillylmandelic acid among the rats submitted to immobilization. In the adrenal glands of stressed animals, there was a decreased level of catecholamines (p<0.01) and no significant changes in corticosteroid content (17-ketosteroids). These results suggest that hypothalamic stimulation and the participation of the adrenal glands are not essential factors in the pathogenesis of restraint-induced experimental stress ulcer. 相似文献
66.
Pedro José Galindo Fernández Julián Illana Moreno Antonio Piñero Madrona Joaquín Sola Pérez Pascual Parrilla Paricio 《Clinical & translational oncology》2004,6(1):45-47
We present a case of hamartoma of the breast. This is an infrequent tumour that requires the correct diagnosis to distinguish it from other histopathology types because it has a better prognosis. The characteristic image from a mammogram is useful in its diagnosis. 相似文献
67.
Joanna Izewska Pedro Andreo Stanislav Vatnitsky Ken R Shortt 《Radiotherapy and oncology》2003,69(1):91-97
BACKGROUND AND PURPOSE: The IAEA/WHO TLD postal programme for external audits of the calibration of high-energy photon beams used in radiotherapy has been in operation since 1969. This work presents a survey of the 1317 TLD audits carried out during 1998-2001. The TLD results are discussed from the perspective of the dosimetry practices in hospitals in developing countries, based on the information provided by the participants in their TLD data sheets. MATERIALS AND METHODS: A detailed analysis of the TLD data sheets is systematically performed at the IAEA. It helps to trace the source of any discrepancy between the TLD measured dose and the user stated dose, and also provides information on equipment, dosimetry procedures and the use of codes of practice in the countries participating in the IAEA/WHO TLD audits. RESULT: The TLD results are within the 5% acceptance limit for 84% of the participants. The results for accelerator beams are typically better than for Co-60 units. Approximately 75% of participants reported dosimetry data, including details on their procedure for dose determination from ionisation chamber measurements. For the remaining 25% of hospitals, who did not submit these data, the results are poorer than the global TLD results. Most hospitals have Farmer type ionisation chambers calibrated in terms of air kerma by a standards laboratory. Less than 10% of the hospitals use new codes of practice based on standards of absorbed dose to water. CONCLUSION: Despite the differences in dosimetry equipment, traceability to different standards laboratories and uncertainties arising from the use of various dosimetry codes of practice, the determination of absorbed dose to water for photon beams typically agrees within 2% among hospitals. Correct implementation of any of the dosimetry protocols should ensure that significant errors in dosimetry are avoided. 相似文献
68.
Adjuvant immunization of HLA-A2-positive melanoma patients with a modified gp100 peptide induces peptide-specific CD8+ T-cell responses. 总被引:3,自引:0,他引:3
John W Smith Edwin B Walker Bernard A Fox Daniel Haley Ketura P Wisner Teri Doran Brenda Fisher Lisa Justice William Wood John Vetto Holden Maecker Annemiek Dols Sybren Meijer Hong-Ming Hu Pedro Romero W Gregory Alvord Walter J Urba 《Journal of clinical oncology》2003,21(8):1562-1573
PURPOSE: To measure the CD8+ T-cell response to a melanoma peptide vaccine and to compare an every-2-weeks with an every-3-weeks vaccination schedule. PATIENTS AND METHODS: Thirty HLA-A2-positive patients with resected stage I to III melanoma were randomly assigned to receive vaccinations every 2 weeks (13 vaccines) or every 3 weeks (nine vaccines) for 6 months. The synthetic, modified gp100 peptide, g209-2M, and a control peptide, HPV16 E7, were mixed in incomplete Freund's adjuvant and injected subcutaneously. Peripheral blood mononuclear cells obtained before and after vaccination by leukapheresis were analyzed using a fluorescence-based HLA/peptide-tetramer binding assay and cytokine flow cytometry. RESULTS: Vaccination induced an increase in peptide-specific T cells in 28 of 29 patients. The median frequency of CD8+ T cells specific for the g209-2M peptide increased markedly from 0.02% before to 0.34% after vaccination (P <.0001). Eight patients (28%) exhibited peptide-specific CD8+ T-cell frequencies greater than 1%, including two patients with frequencies of 4.96% and 8.86%, respectively. Interferon alfa-2b-treated patients also had significant increases in tetramer-binding cells (P <.0001). No difference was observed between the every-2-weeks and the every-3-weeks vaccination schedules (P =.59). CONCLUSION: Flow cytometric analysis of HLA/peptide-tetramer binding cells was a reliable means of quantifying the CD8+ T-cell response to peptide immunization. This assay may be suitable for use in future trials to optimize different vaccination strategies. Concurrent interferon treatment did not inhibit the development of a peptide-specific immune response and vaccination every 2 weeks, and every 3 weeks produced similar results. 相似文献
69.
Angel Asensio Antonio Ramos Elena Mú?ez José L Vilanova Pedro Torrijos Fernando J García 《Infection control and hospital epidemiology》2005,26(12):903-909
OBJECTIVE: To investigate the effect of preoperative initiation of low molecular weight heparin as prophylaxis for deep venous thrombosis in patients at risk of developing surgical-site infections after knee arthroplasty. DESIGN: Case-control study nested in a cohort. The incidence of surgical-site infection in the cohort was calculated. With the use of data extracted from medical histories and after adjustment for other risk factors, the effect of preoperative heparinization on the risk of incisional and prosthetic infection among case-patients and control-patients (1:3 ratio) was assessed. SETTING: Orthopedic department in a tertiary-care referral hospital. PATIENTS: A cohort of 160 consecutive patients who had received prosthetic knee implants between October 1, 2001, and November 30, 2003. RESULTS: Eighteen patients with surgical-site infections were identified, yielding an incidence of incisional and prosthetic infection of 6.9 (95% confidence interval [CI95], 3.5 to 12.0) and 4.4 (CI95, 1.8 to 8.8) cases per 100 patients undergoing surgery, respectively. Surgical-site infection was associated with preoperative use of low molecular weight heparin (odds ratio [OR], 6.2 after adjustment for medical and surgical factors; CI95 1.5 to 23). Prosthetic infection was strongly associated with preoperative use of prophylaxis (OR, undetermined [100% exposure in case-patients vs 35% exposure in control-patients]; P = .002), but incisional surgical-site infection was not. CONCLUSION: The use of low molecular weight heparins immediately before knee arthroplasty as prophylaxis for deep venous thrombosis should be questioned because of probable increased risk of prosthetic infection. 相似文献
70.
Changes in the Household Calorie Supply during the 1994 Economic Crisis in Mexico and Its Implications on the Obesity Epidemic 总被引:2,自引:0,他引:2
Pedro Arroyo M.D. M.P.H. M.Sc. Alvar Loria Ph.g. Oscar Méndez B.S. 《Nutrition reviews》2004,62(S2):S163-S168
To characterize the effects of the 1994 economic crisis on calorie sources of Mexican households, five nutrition surveys done every leap year (1992–2000) in national representative samples (> 10,000 households) were analyzed. Each household was visited during 7 days to collect data on foods purchased, exchanged or home-grown and their monetary value. We selected 88 food items to calculate kilocalories/ person/day and cost in pesos/megacalorie (CPMC) for rural-urban strata (localities <2500, ≥2500). The food items were classified in 8 groups and the summation of kilocalories and CPMCs of items in each group were our units of analysis. Linear regressions for 1992–2000 were performed, and slopes and intercepts were used to characterize changes. Available calories showed very little change at the height of the economic crisis. Expensive calories (meat in ur-bans, eggs and milk in rurals, and industrialized meat and soft drinks in both) tended to increase, whereas the most inexpensive staples (cereals, legumes, sugars) decreased their share in both strata. An increase in obesigenic calories was seen, notably in soft drinks, despite a cost increase second only to meat. Main conclusions were: (1) the economic crisis did not affect total calories availability in Mexican households; (2) the 1992–2000 trends in calorie sources were contrary to any crisis effect in rurals and urbans (i.e., expensive foods increased and inexpensive staples decreased); (3) there were sizable rural-urban differences in number, source, and cost of calories; and (4) obesigenic calories increased and soft drinks emerged as a food with its own dynamic. 相似文献