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1.
J Laryngol Otol ; 132(7): 651-656, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29893657

RESUMEN

OBJECTIVES: To analyse publication and citations trends of case reports within otolaryngology - head and neck surgery literature, with specific attention to the most-cited reports.Study designDatabase query. METHODS: Web of Science was searched for article type 'case reports' published in the leading otolaryngology - head and neck surgery journals since 1945. Variables including publication dates, citation dates and numbers, author, author number, and others were recorded and analysed for trends. The reports with the most citations (classics) were further studied. RESULTS: Of nearly 67 000 published articles in leading otolaryngology - head and neck surgery journals, the overall number of case reports as a percentage of the total has substantially decreased over time. A total of 110 case report classics were identified for which citations have increased. CONCLUSION: Although the case report may not be worthy of its tarnished record, declining trends in publication suggest a limited future for this valuable research and educational resource.


Asunto(s)
Bibliometría , Registros Médicos , Otolaringología/tendencias , Procedimientos Quirúrgicos Otorrinolaringológicos , Humanos
2.
Phys Rev Lett ; 92(9): 091801, 2004 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-15089459

RESUMEN

We observe a net beam excess of 8.7+/-6.3(stat)+/-2.4(syst) events, above 160 MeV, resulting from the charged-current reaction of nu(micro) and/or nu;(mu) on C and H in the LSND detector. No beam-related muon background is expected in this energy regime. Within an analysis framework of pi(0)-->nu(mu)nu;(mu), we set a direct upper limit for this branching ratio of Gamma(pi(0)-->nu(mu)nu;(mu))/Gamma(pi(0)-->all)<1.6 x 10(-6) at 90% confidence level.

3.
Phys Rev Lett ; 87(4): 041601, 2001 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-11461607

RESUMEN

Solar, atmospheric, and LSND neutrino oscillation results require a light sterile neutrino, nu(B), which can exist in the bulk of extra dimensions. Solar nu(e), confined to the brane, can oscillate in the vacuum to the zero mode of nu(B) and via successive Mikheyev-Smirnov-Wolfenstein transitions to Kaluza-Klein states of nu(B). This new way to fit solar data is provided by both low and intermediate string scale models. From average rates seen in the three types of solar experiments, the Super-Kamiokande spectrum is predicted with 73% probability, but dips characteristic of the 0.06 mm extra dimension should be seen in the SNO spectrum.

4.
Facial Plast Surg ; 13(4): 231-9, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9656878

RESUMEN

The approach of a new millenium provides us, as rhinoplasty surgeons, the opportunity to reflect on where we are and where we are going. Aesthetically, there are several trends that are evident today. The first is the desire for a natural, unoperated appearance to the final rhinoplasty result. Second, is that our patient population continues to be more racially diverse; Caucasian normative standards of facial analysis are no longer sufficient. What is required is a broader understanding of ethnically specific facial features. Third, the standard values of facial and nasal analysis are derived from population means. If we desire to create beauty, these standards may not be adequate. Beauty is an ill-defined concept that is obvious to the observer and recognized cross-culturally, however, it is difficult to quantify. To consistently achieve beautiful rhinoplasty results, we must start with an understanding of what our aesthetic ideals should be. This has yet to be satisfactorily defined for all racial groups and remains a challenge for the future.


Asunto(s)
Cara/anatomía & histología , Nariz/anatomía & histología , Rinoplastia , Belleza , Estética/psicología , Humanos , Grupos Raciales
7.
Ann Otol Rhinol Laryngol ; 105(7): 510-5, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8678425

RESUMEN

The treatment of laryngeal and hypopharyngeal hemangiomas is indicated when they are symptomatic, causing dysphagia, recurrent bleeding, or airway obstruction. These tumors are found in the glottis, supraglottic larynx, and hypopharynx. Histologically, they are considered as mixed or cavernous-type hemangiomas. By utilizing a glass slide to compress the lesion, its thickness and blood flow are reduced. The tumor can then be laser-photocoagulated with less energy, with the glass slide used as a laser platform. These conditions optimize the benefits of laser ablation while minimizing the adverse heat sink effects to the surrounding healthy tissue. We present three patients with hemangiomas of the larynx and hypopharynx who were treated with this technique. The details of the technique in each case will be presented with the objective of improving the care of these unusual and challenging tumors.


Asunto(s)
Hemangioma/cirugía , Neoplasias Hipofaríngeas/cirugía , Hipofaringe/cirugía , Neoplasias Laríngeas/cirugía , Laringe/cirugía , Terapia por Láser , Adulto , Femenino , Estudios de Seguimiento , Hemangioma/patología , Humanos , Neoplasias Hipofaríngeas/patología , Hipofaringe/patología , Neoplasias Laríngeas/patología , Laringe/patología , Persona de Mediana Edad
9.
Otolaryngol Head Neck Surg ; 112(4): 544-8, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7700660

RESUMEN

Bone marrow transplantation for the treatment of leukemia is increasingly successful in rendering patients disease free. However, it has become evident that the associated severe immunosuppression predisposes this population to an increased risk for other neoplastic disorders. We report on six patients in whom non-Hodgkin's lymphoma of the tonsillar region developed within 5 months after T-cell-depleted bone marrow transplantation for the treatment of leukemia at Memorial Sloan-Kettering Cancer Center from October 1990 to October 1992. These patients initially had what appeared to be infectious exudative pharyngitis/tonsillitis; however, they did not improve with medical therapy. Because of the persistence of pharyngitis/tonsillitis in association with cervical lymphadenopathy and odynophagia, the patients underwent definitive biopsy in the form of tonsillectomy, cervical lymph node biopsy, or both. Histopathologic review revealed non-Hodgkin's lymphoma. An association with Epstein-Barr virus has been noted in five of these patients. This article is aimed at alerting the clinician to consider the diagnosis of lymphoma in a patient with persistent pharyngitis/tonsillitis despite adequate medical therapy after bone marrow transplantation.


Asunto(s)
Trasplante de Médula Ósea/efectos adversos , Herpesvirus Humano 4/aislamiento & purificación , Leucemia Mieloide/terapia , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/etiología , Neoplasias Primarias Secundarias/diagnóstico , Neoplasias Tonsilares/diagnóstico , Neoplasias Tonsilares/etiología , Tonsilitis/etiología , Adulto , Femenino , Humanos , Tolerancia Inmunológica , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Leucemia Mieloide Aguda/terapia , Linfoma de Células B Grandes Difuso/microbiología , Masculino , Persona de Mediana Edad , Neoplasias Tonsilares/microbiología , Tonsilitis/microbiología , Infecciones Tumorales por Virus/diagnóstico
11.
Cancer Lett ; 85(2): 223-32, 1994 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-7954341

RESUMEN

Factors controlling glutathione metabolism may govern sensitivity to chemotherapeutic agents such as cisplatin. Using a battery of cell lines derived from previously untreated head and neck squamous cell carcinomas, we examined cisplatin resistance relative to (a) glutathione-S-transferase (GST)-pi gene amplification and expression, (b) basal and inducible GST-total and GST-pi enzymatic activity, and (c) cellular levels of reduced glutathione (GSH). Using Southern blot analysis and northern blot hybridization, no relationship between GST-pi gene amplification, mRNA expression and drug resistance could be identified. Despite the capacity of cisplatin to induce GST enzyme activity, the response was variable and unrelated to cisplatin responsiveness. However, an inverse relationship between GSH levels and cisplatin sensitivity was identified. To further clarify these effects, cells were treated with S-allyl cysteine (SAC), a thioallyl derivative isolated from garlic (Allium sativum), which altered cellular GSH in a biphasic manner. Pretreatment with SAC to lower cellular GSH levels followed by exposure to cisplatin significantly enhanced the cytotoxic effects of cisplatin, while SAC alone had no effect on cell growth.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Cisplatino/toxicidad , Glutatión Transferasa/metabolismo , Glutatión/metabolismo , Neoplasias de Cabeza y Cuello/fisiopatología , Carcinoma de Células Escamosas/genética , Supervivencia Celular/efectos de los fármacos , Cromosomas Humanos Par 11 , Cisteína/administración & dosificación , Cisteína/análogos & derivados , Amplificación de Genes , Regulación Neoplásica de la Expresión Génica , Glutatión Transferasa/genética , Humanos , Técnicas In Vitro , ARN Mensajero/genética , Células Tumorales Cultivadas
13.
Am Surg ; 55(7): 413-6, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2742224

RESUMEN

The efficacy and associated morbidity and mortality of gastrostomy (G) versus nasogastric (NG) tube decompression after gastric surgery were analyzed in a review of 100 patients. Age, sex, and risk factors were homogeneously distributed between the two groups, while perforated ulcers and emergency operations were more common in the G group. A gastrostomy did not completely eliminate the need for NG tube decompression in the G group. Postoperative morbidity was similar in the two groups, with the exception of an increased incidence of atelectasis in the elective NG group and increased mortality in the emergency G group. There was also a significant increase in length and cost of hospitalization in the emergency G group compared with emergency NG patients. Gastrostomy does not appear to offer any significant advantage over nasogastric decompression after gastric surgery and should be limited to special cases.


Asunto(s)
Gastrostomía , Intubación Gastrointestinal , Estómago/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Evaluación como Asunto , Femenino , Gastrostomía/efectos adversos , Gastrostomía/economía , Humanos , Intubación Gastrointestinal/efectos adversos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Úlcera Péptica Perforada/complicaciones , Úlcera Péptica Perforada/cirugía , Cuidados Posoperatorios , Complicaciones Posoperatorias , Estudios Retrospectivos
14.
J Trauma ; 27(2): 167-75, 1987 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3820352

RESUMEN

The purpose of this study was to determine whether or not thromboxane A2 (TXA2) was necessary or sufficient for the development of end-organ pathology during graded bacteremia. Pulmonary artery catheters were placed in 21 adult male pigs under pentobarbital anesthesia and breathing room air. After a control period, animals were studied in four groups: Group 1, anesthesia only; Group 2, infusion of 1 X 10(9) ml Aeromonas hydrophila which was gradually increased from 0.2 ml/kg/hr to 4.0 ml/kg/hr over 4 hours; Group 3, pretreatment with SQ 29,548 (TXA2 antagonist) then Aeromonas h. infusion; Group 4, infusion of U46619 (TXA2 agonist) to pulmonary artery pressures measured in Group 2. Animals were sacrificed after 4 hours and the lungs, liver, spleen, kidneys, and heart were examined under light microscopy by a pathologist unaware of study groups. The results indicated that physiologic thromboxane A2 agonist (Group 4) was sufficient alone to cause pulmonary inflammation. Thromboxane A2 was neither necessary nor sufficient for significant renal, hepatic, pulmonary, or splenic pathology to occur in graded bacteremia, manifested in similar microanatomic abnormalities in these organs in Groups 2 and 3 and in Groups 1 and 4. Pulmonary leukocyte infiltration was significantly increased in Group 3 compared to all other groups, suggesting that TXA2 impairs inflammatory responses.


Asunto(s)
Sepsis/patología , Tromboxano A2/sangre , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes , Ácidos Grasos Insaturados , Hidrazinas/farmacología , Riñón/patología , Hígado/patología , Pulmón/patología , Masculino , Miocardio/patología , Endoperóxidos de Prostaglandinas Sintéticos/farmacología , Radioinmunoensayo , Sepsis/sangre , Bazo/patología , Porcinos , Tromboxano B2/análisis
15.
Surgery ; 100(2): 214-21, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3526603

RESUMEN

Thromboxane A2 has been implicated as a mediator of cardiorespiratory dysfunction in sepsis. This study evaluated whether or not thromboxane A2 was necessary or sufficient for these adverse effects to occur during bacteremia. Fourteen adult swine under barbiturate anesthesia and breathing room air were monitored with arterial and pulmonary artery catheters. Animals were studied for 4 hours in three groups: group I, graded infusion of 10(9)/ml Aeromonas hydrophila; group II, Aeromonas hydrophila infusion plus SQ 29,548 (thromboxane A2 antagonist); and group III, U46619 (thromboxane A2 agonist) infusion in normal swine to pulmonary artery pressures observed in group I. Hemodynamic parameters, arterial and mixed venous blood gases, and plasma thromboxane B2 and prostaglandin 6-keto-F1 were measured. At sacrifice after 4 hours, wet-to-dry lung weights were calculated. Results indicated that thromboxane A2 was necessary and sufficient for the development of pulmonary hypertension and impaired alveolar-capillary oxygen diffusion in graded bacteremia. It was necessary but not sufficient for increased lung water to occur and sufficient but not necessary for decreased cardiac index and stroke volume index. Thromboxane A2 was neither sufficient nor necessary to the pathophysiology of systemic hypotension during graded bacteremia. Plasma prostaglandin 6-keto-F1 levels were increased in hypotensive animals with sepsis, suggesting its involvement in hypotension during sepsis.


Asunto(s)
Hemodinámica , Hipertensión Pulmonar/fisiopatología , Intercambio Gaseoso Pulmonar , Sepsis/fisiopatología , Tromboxano A2/fisiología , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico , Aeromonas , Animales , Presión Sanguínea , Compuestos Bicíclicos Heterocíclicos con Puentes , Permeabilidad Capilar , Gasto Cardíaco , Epoprostenol/sangre , Ácidos Grasos Insaturados , Hidrazinas/farmacología , Hipoxia/fisiopatología , Masculino , Endoperóxidos de Prostaglandinas Sintéticos/farmacología , Choque Séptico/fisiopatología , Porcinos , Tromboxano A2/antagonistas & inhibidores , Tromboxano B2/sangre
16.
Surgery ; 99(6): 744-51, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3520916

RESUMEN

Activated complement, thromboxane A2, prostacyclin, and activated granulocytes have been implicated in hemodynamic dysfunction after trauma, in sepsis, and in hypovolemic and septic shock. This study evaluated the interaction of plasma concentrations of complement components C3a and C5a, thromboxane B2 (TxB), prostaglandin 6-keto-F1 alpha (PGI), and granulocyte aggregation in clinical sepsis and hypotension. Forty-eight critically ill patients were followed clinically for as long as 10 days. Plasma C3a, C5a, TxB, and PGI were measured daily by the radioimmunoassay method. Granulocyte aggregation, the percentage of maximum aggregation of zymosan-activated plasma standard curves, was performed with patient plasma and normal human leukocytes. Patients were studied in four groups: group I, nonseptic, normotensive; group II, hypovolemic shock, group III, normotensive severe sepsis; and group IV, septic shock. Plasma from 12 normal adults was the control value. PGI, TxB, C3a, C5a, and granulocyte aggregation in patients were greater than that in the control subjects. Granulocyte aggregation was increased in groups III and IV versus groups I and II. C3a was increased in group IV versus groups II and III. C5a and TxB did not vary between groups. PGI was greatly increased in group IV compared with groups I through III. C3a and C5a decreased in nonsurvivors. PaO2/FiO2 ratios correlated directly with PGI and inversely with C3a and TxB/PGI. Plasma PGI and C3a are increased in septic shock. C3a and TxB/PGI imbalances are involved in hypovolemic and septic shock.


Asunto(s)
Activación de Complemento , Granulocitos/inmunología , Hipotensión/inmunología , Infecciones/inmunología , Prostaglandinas/sangre , Adolescente , Adulto , Anciano , Agregación Celular , Complemento C3/análisis , Complemento C3a , Complemento C5/análisis , Complemento C5a , Epoprostenol/sangre , Femenino , Humanos , Hipotensión/sangre , Infecciones/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radioinmunoensayo , Choque Séptico/sangre , Tromboxano B2/sangre
17.
Arch Surg ; 121(3): 305-7, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3484946

RESUMEN

Granulocyte aggregation (GA) response has previously been described as a sensitive assay for complement activation in sepsis. Complement component C5a has been implicated as the plasma factor responsible for GA. The quantitative interaction of complement components C3a and C5a with GA, however, is not clearly defined. This study evaluates the relationship of GA responses to plasma levels of C5a and C3a in zymosan-activated plasma (ZAP). The C3a and C5a levels were measured by radioimmunoassay in serial dilutions of ZAP. Granulocyte aggregation responses of normal human leukocytes were determined for each ZAP dilution. The C5a levels in a 1:16 dilution of ZAP were higher than in normal plasma (22 +/- 7 vs 9 +/- 3 ng/mL), as were GA responses (24 +/- 1 vs 11 +/- 2 percentage of maximum light transmission). The C3a levels in a 1:8 dilution of ZAP are elevated above those of normal plasma (656 +/- 167 vs 411 +/- 29 ng/mL). Correlation coefficients were .9809 for C3a vs GA, .9788 for C5a vs G, and .9860 for C3a vs C5a. Complement components C3a and C5a are involved in GA in vitro. Granulocyte aggregometry can detect low levels of activated complement in ZAP but may not be specific for C5a. The relative contribution of C3a and C5a to observed GA is not clear from the data.


Asunto(s)
Complemento C3/análisis , Complemento C5/análisis , Leucocitos/inmunología , Agregación Celular , Activación de Complemento/efectos de los fármacos , Complemento C3a , Complemento C5a , Estudios de Evaluación como Asunto , Humanos , Técnicas In Vitro , Métodos , Radioinmunoensayo , Zimosan/farmacología
18.
Arch Surg ; 121(3): 271-4, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3511889

RESUMEN

This study investigated the interaction of plasma levels of circulating prostaglandins and activated complement in clinical acute respiratory failure (ARDS). Fifty patients at risk for ARDS were followed up for up to ten days. Arterial blood gases and plasma levels of complement components C3a and C5a, thromboxane B2 (TxB), and prostaglandin 6-keto-F1 alpha (PGI) and granulocyte aggregation (GA) were measured daily. Seventeen patients (34%) developed ARDS, with mortality of 41% vs 23% for patients without ARDS. Compared with patients without ARDS, the ARDS group had significantly increased plasma C3a (1,130 +/- 750 vs 636 +/- 368 ng/mL) and granulocyte aggregation (48 +/- 10 vs 17 +/- 4 percentage of the maximum light transmission [% max T]). Plasma C5a, TxB, or PGI did not change significantly with or without ARDS. No measured variable was significantly associated with mortality. Regression analysis revealed significant correlations between GA, TxB, PGI, and arterial oxygenation. Plasma C3a and GA are increased in ARDS, suggesting systemic complement activation. A complex series of interactions between the prostaglandins, complement, and GA appears to be involved in ARDS.


Asunto(s)
Complemento C3/análisis , Complemento C5/análisis , Epoprostenol/sangre , Síndrome de Dificultad Respiratoria/sangre , Tromboxano A2/sangre , Enfermedad Aguda , Adolescente , Adulto , Anciano , Agregación Celular , Activación de Complemento , Complemento C3a , Complemento C5a , Femenino , Granulocitos/fisiología , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Estudios Prospectivos , Radioinmunoensayo , Análisis de Regresión , Síndrome de Dificultad Respiratoria/inmunología
19.
Circ Shock ; 20(4): 291-7, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3539388

RESUMEN

Prostacyclin and thromboxane A2 have been implicated as mediators of septic shock. Correlations between the human prostanoid response to sepsis and experimental paradigms are poorly understood. The purpose of this study was to compare changes in plasma levels of prostaglandin 6-keto-F1 alpha (PGI) and thromboxane B2 (TxB) during septic shock in Sprague-Dawley rats, domestic pigs, mongrel dogs, and man. Severe sepsis followed by septic shock (systolic BP less than 90 mmHg) was induced in rats by inoculation of 1.0 X 10(9) Aeromonas hydrophila, in pigs by graded IV infusion of 1.0 X 10(9)/ml A. hydrophila; and in dogs by an IV bolus injection of 5.0 X 10(9)/ml Escherichia coli. Plasma PGI and TxB (pg/ml) were measured by radioimmunoassay in control, septic, and septic shock experimental blood samples, and in normal controls, severly septic, and septic shock (systolic BP less than 90 mmHg) S.I.C.U. patients. Control, septic, and septic shock TxB levels in the dog and the pig were significantly greater than in the rat and man. PGI levels in the dog were significantly greater than in other species. TxB increased significantly in murine sepsis and PGI increased significantly in sepsis and septic shock. TxB increased during porcine sepsis and septic shock. In man, both PGI and TxB were significantly increased in severe sepsis, compared to normal controls, but only PGI was significantly higher in septic shock versus normotensive sepsis. Patterns of change in TxB/PGI ratios were similar for all species studied. Changes in PGI in the porcine septic experiments most closely paralleled those observed clinically.


Asunto(s)
Epoprostenol/sangre , Choque Séptico/sangre , Tromboxano A2/sangre , Animales , Perros , Femenino , Humanos , Masculino , Ratas , Ratas Endogámicas , Especificidad de la Especie , Porcinos
20.
Circ Shock ; 19(3): 275-82, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3524892

RESUMEN

UNLABELLED: Cardiorespiratory dysfunction in sepsis may be mediated by circulating complement, activated leukocytes, prostaglandins, or by a direct effect of endotoxin. The purposes of this study were to determine if pathogenic microbes produce these substances and to evaluate the direct effects of substances released by micro-organisms on granulocyte aggregation (GA). Escherichia coli, (E. coli), Aeromonas hydrophila (Aeromonas h.), Staphylococcus aureus (S. aureus), and Candida albicans, (Candida a.) were incubated in broth to a concentration of 10(9)/ml. Broth was filtered and analyzed by radioimmunoassay for complement components C3a and C5a, thromboxane B2 (TxB), and prostaglandin 6-keto-F1 alpha (PGI) and by the limulus amebocyte lysate test (LAL) for endotoxin. GA, % of maximum zymosan activated aggregation (% max. T), was performed with broth, microbial filtrates, and endotoxin or normal purified human leukocytes in HBSS. Organisms were incubated in broth (B), broth + 0.0135 mg/ml arachidonic acid (BA), and broth + arachidonic acid + indomethacin (BAI). Broth alone was the control (C). RESULTS: C3a, C5a, TxB, and PGI were not detectable in C broth or in any microbian filtrate. LAL was positive in all filtrates, but negative in C broth. GA responses were significantly greater in E. coli (56 +/- 5% max T) and Aeromonas h. (57% +/- 8% max T) compared to S. aureus (10 +/- 5% max T), Candida a. (14 +/- 8% max T) and C broth (1 +/- 1% max T). GA with purified E. coli endotoxin at concentrations measured in the filtrates was not related to the GA responses the original filtrates.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Bacterias/metabolismo , Candida albicans/metabolismo , Endotoxinas/metabolismo , Granulocitos/fisiología , Agregación Celular , Proteínas del Sistema Complemento/análisis , Endotoxinas/farmacología , Filtración , Prueba de Limulus , Prostaglandinas/análisis
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