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1.
Opt Lett ; 37(12): 2328-30, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22739897

RESUMO

We demonstrate a novel method to spectroscopically detect and identify trace gases. Micromechanical photothermal spectroscopy (MPS) with functionalized sorbent materials provides trace gas spectra in an optical interaction length of only a few micrometers. We use microcavity interferometry to read out displacements as low as 25 fm/√Hz, heating as low as 200 pW/√Hz, and analyte concentrations as low as 65 parts-per-billion for the nerve agent simulant DMMP. MPS integrated with functional materials represents an important new tool in chip-scale optical sensing.


Assuntos
Gases/análise , Fenômenos Mecânicos , Polímeros/química , Análise Espectral/métodos , Gases/química , Interferometria , Luz , Fenômenos Ópticos , Análise Espectral/instrumentação , Volatilização
2.
Opt Express ; 16(4): 2423-30, 2008 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-18542321

RESUMO

We describe a new class of micro-opto-mechanical chemical sensors: A photonic microharp chemical sensor is an array of closely spaced microbridges, each differing slightly in length and coated with a different sorbent polymer. They are optically interrogated using microcavity interferometry and photothermal actuation, and are coupled directly to an optical fiber. Simultaneous measurements of the fundamental flexural resonant frequency of each microbridge allow the real-time detection and discrimination of a variety of vapor-phase analytes, including DMMP at concentrations as low as 17 ppb.

3.
Am J Surg Pathol ; 19(2): 134-44, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7832273

RESUMO

We describe 11 patients first seen with symptoms or signs related to lymphoma predominantly or exclusively involving one or both kidneys. The patients were seven men and four women, aged 40-77 years (median, 67). Seven of them had one or more other prior (four), subsequent (two) or both simultaneous and subsequent (one) primary malignant or premalignant lesions. The presenting symptoms of the patients with lymphoma included local pain (five cases), loss of appetite or nausea (four cases), hematuria (two cases), weight loss (two cases) or malaise (two cases). One patient had renal failure at presentation. One lymphoma was an incidental finding at the time of aneurysm resection. Nine patients had unilateral disease; two patients had bilateral disease. Six unilateral cases were initially considered on clinical (five) or clinical and pathological (one) evaluation to be primary carcinomas of the kidney. Gross examination of nephrectomy specimens revealed fleshy or firm, yellow, tan, or gray tumors from 5.7 to 22 cm (median, 7.5) in greatest dimensions that frequently invaded perinephric fat and adjacent structures. The lymphomas were subclassified as diffuse large cell (seven cases), follicular and diffuse large cell (one case), small lymphocytic plasmacytoid (two cases), and small noncleaved cell lymphoma (non-Burkitt's type) (one case). Immunophenotyping in nine cases revealed that all were B-lineage tumors. Three patients had Ann Arbor stage I disease, three had stage II, and five had stage IV. On follow-up, ranging from 1 week to 169 months (median, 15 months), 5 patients were alive and free of lymphoma. Four patients died of progressive disease 1 week to 23 months after diagnosis. One patient is alive at 4 months but has not completed chemotherapy. One asymptomatic patient has not been treated. Renal lymphomas are predominantly large-cell lymphomas of B-lineage affecting middle-aged and older adults and often can be treated successfully. Both clinically and pathologically, they can be mistaken for carcinomas of the kidney. A high proportion of patients in this series had malignant tumors of other types.


Assuntos
Neoplasias Renais/patologia , Linfoma/patologia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Imunofenotipagem , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/terapia , Linfoma/diagnóstico por imagem , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radiografia
4.
J Nucl Med ; 19(5): 501-3, 1978 May.
Artigo em Inglês | MEDLINE | ID: mdl-641572

RESUMO

A cisternogram characteristic of normal-pressure hydrocephalus was obtained from a patient on Diamox who was being evaluated for rapid mental deterioration. A repeat cisternogram after Diamox was discontinued was nearly normal. We hypothesize that the initial abnormality resulted from reduced cerebrospinal fluid production caused by carbonic anhydrase inhibition; this defect (reduced flow) led to a net reflux of tracer into the ventricles. The reflux is believed to be due to the reduction of bulk cerebrospinal fluid from the ventricles.


Assuntos
Acetazolamida/efeitos adversos , Demência/diagnóstico por imagem , Hidrocefalia de Pressão Normal/tratamento farmacológico , Hidrocefalia/tratamento farmacológico , Acetazolamida/uso terapêutico , Idoso , Cisterna Magna , Humanos , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Índio/administração & dosagem , Masculino , Ácido Pentético/administração & dosagem , Ácido Pentético/uso terapêutico , Cintilografia
5.
J Nucl Med ; 23(3): 209-13, 1982 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7199566

RESUMO

Ten children underwent splenic imaging with heat-denatured red blood cells labeled with technetium-99m (Tc-99m DRBC). The presenting problems included the heterotaxia syndrome, recurrent idiopathic thrombocytopenic purpura following splenectomy, mass in the left posterior hemithorax, and blunt abdominal trauma. In nine patients, the presence or absence of splenic tissue was established. A splenic hematoma was identified in the tenth patient. All patients were initially scanned with Tc-99m sulfur colloid (Tc-99m SC), and were selected for Tc-99m DRBC scintigraphy only after the results of the SC scans failed to establish the clinical problem beyond doubt. The availability of kits containing stannous ions, essential for efficient and stable labeling of red blood cells with Tc-99m and requiring only a small volume of blood, make splenic scintigraphy in children a relatively simple and definitive diagnostic procedure, when identification of splenic tissue is of clinical importance.


Assuntos
Eritrócitos , Baço/diagnóstico por imagem , Tecnécio , Traumatismos Abdominais/diagnóstico por imagem , Adolescente , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Marcação por Isótopo , Masculino , Púrpura Trombocitopênica/diagnóstico por imagem , Cintilografia , Kit de Reagentes para Diagnóstico , Baço/anormalidades , Enxofre , Síndrome , Coloide de Enxofre Marcado com Tecnécio Tc 99m
6.
Am J Cardiol ; 49(4): 761-5, 1982 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7064826

RESUMO

The ability of first pass radionuclide angiocardiography to detect and quantitate residual intracardiac shunts and systemic venous obstruction after repair of transposition of the great arteries was evaluated in 29 children. Information from radionuclide scans was compared with data obtained during cardiac catheterization. Three children had a residual right to left shunt detected with both methods. There was good agreement between radionuclide and catheterization quantitation of left to right shunt in the nine patients with a residual defect, five of whom had significant shunting. Nineteen patients with signs suggesting superior vena caval obstruction were evaluated with both radionuclide and catheterization methods. In eight, complete obstruction was detected with both techniques; in one additional patient, partial obstruction was found on catheterization only. One of six patients evaluated for possible inferior vena caval obstruction was identified with both techniques. In the group as a whole, information obtained with radionuclide angiography correlated well with cardiac catheterization data in evaluation of residual shunts and obstruction to systemic venous return.


Assuntos
Complicações Pós-Operatórias/diagnóstico por imagem , Transposição dos Grandes Vasos/cirurgia , Adolescente , Cateterismo Cardíaco , Criança , Pré-Escolar , Constrição Patológica , Vasos Coronários/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido , Cintilografia , Transposição dos Grandes Vasos/diagnóstico por imagem , Veia Cava Superior/diagnóstico por imagem
7.
Semin Nucl Med ; 10(3): 259-85, 1980 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6997999

RESUMO

Pulmonary radionuclide studies in children provide reliable information on regional lung perfusion and ventilation. They are easily and safely performed and they do not usually require full patient cooperation. Their clinical indications and applications are not as well defined as and frequently differ from those in pulmonary disorders of the adult patient. Radiation exposures resulting from radionuclide pulmonary examinations are well within acceptable limits set up for a variety of radiologic diagnostic procedures. Our lung scanning experience with a spectrum of congenital and acquired cardiopulmonary diseases is presented and the contribution of the radionuclide methods to the specific problems facing the pediatrician or the surgeon is discussed.


Assuntos
Pneumopatias/diagnóstico por imagem , Adolescente , Adulto , Asma/diagnóstico por imagem , Brônquios/diagnóstico por imagem , Bronquiectasia/diagnóstico por imagem , Sequestro Broncopulmonar/diagnóstico por imagem , Pré-Escolar , Fibrose Cística/diagnóstico por imagem , Feminino , Corpos Estranhos/diagnóstico por imagem , Tórax em Funil/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas , Humanos , Lactente , Recém-Nascido , Masculino , Pneumonia/diagnóstico por imagem , Artéria Pulmonar/anormalidades , Embolia Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/diagnóstico por imagem , Cintilografia , Síndrome , Deficiência de alfa 1-Antitripsina
8.
Leuk Lymphoma ; 16(1-2): 37-50, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7696930

RESUMO

Renal lymphoma usually is a manifestation of disseminated disease and often is asymptomatic. Occasionally, the kidney(s) may be the major or only demonstrable site of disease, which may then present with a variety of urologic symptoms. The imaging studies should be tailored according to the presenting symptoms and prior history. Currently CT with intravenous contrast material enhancement is the study of choice for both the evaluation of renal involvement as well as staging of the disease. When necessary, CT or sonography may be used to guide percutaneous needle biopsy of suspicious masses. The role of the various imaging techniques, including MR and positron emission tomography, in the evaluation of renal lymphoma is discussed.


Assuntos
Neoplasias Renais/diagnóstico , Linfoma/diagnóstico , Angiografia , Humanos , Neoplasias Renais/patologia , Transplante de Rim/efeitos adversos , Linfoma/patologia , Linfoma Relacionado a AIDS/diagnóstico , Linfoma Relacionado a AIDS/patologia , Imageamento por Ressonância Magnética , Cintilografia , Tomografia Computadorizada por Raios X , Ultrassonografia , Urografia
9.
Radiol Clin North Am ; 34(5): 965-95, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8784392

RESUMO

Most adults with uncomplicated acute pyelonephritis pose no diagnostic or therapeutic problems and recover fully. When imaging is requested in these cases, CT scan with and without contrast enhancement is preferable; however, depending on the condition of the patient and preference of the clinician an IVU, sonogram, or radionuclide scan may also provide adequate information. Patients at higher risk for complications, such as renal or perinephric abscesses with or without PHN and EPN, require aggressive and vigorous clinical and radiologic monitoring. CT scan is superior to other imaging modalities in the investigation of these complications. Interventional percutaneous procedures are established as safe and effective means of controlling or curing the infection in many patients and are often chosen over traditional surgical technique. The radiologist thus is an indispensable member of the management team and should be available for consultation and intervention.


Assuntos
Infecções Bacterianas/diagnóstico , Pielonefrite/diagnóstico , Doença Aguda , Infecções Bacterianas/terapia , Humanos , Hidronefrose/complicações , Rim/diagnóstico por imagem , Pielonefrite/complicações , Pielonefrite/terapia , Cintilografia , Tomografia Computadorizada por Raios X , Ultrassonografia , Urografia
10.
Radiol Clin North Am ; 24(4): 561-71, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3786683

RESUMO

Diagnostic antegrade pyelography, with a thin needle, is basically a simple procedure that can be performed relatively rapidly under local anesthesia with few complications of significance. Its role, however, is frequently crucial to subsequent patient management. During morphologic antegrade examination, aspirated urine can be analyzed for tumor cells (cytologic examination), infection (smear, culture), or other biochemical alterations. The use of antegrade pyelography in the demonstration of internal diversion, ureteral fistula, and the site and cause of obstruction is well established. Dynamic antegrade study is crucial in the assessment of many pyeloureteral units in which the issue of current obstruction is equivocal or uncertain. Absolute renal and bladder pressures are obtained simultaneously; these and the calculated differential pressure provide objective data relative to ureteral resistance to urine flow and renal nephron preservation.


Assuntos
Urografia , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução Ureteral/diagnóstico por imagem
11.
Eur J Gastroenterol Hepatol ; 13(1): 59-61, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11204812

RESUMO

Gastric outlet (GO) obstruction in an adult is usually caused by intrinsic gastric or duodenal lesions or pancreatic tumours. This study describes a case of a 77-year-old man who developed GO obstruction due to extrinsic compression from a large gastroduodenal artery aneurysm under rupture. This cause of GO obstruction has never previously been reported in the literature.


Assuntos
Aneurisma/complicações , Duodeno/irrigação sanguínea , Obstrução da Saída Gástrica/etiologia , Estômago/irrigação sanguínea , Idoso , Aneurisma/diagnóstico por imagem , Aneurisma Roto/complicações , Artérias , Evolução Fatal , Humanos , Masculino , Tomografia Computadorizada por Raios X , Ultrassonografia
12.
Eur J Obstet Gynecol Reprod Biol ; 80(2): 227-9, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9846674

RESUMO

The incidence of HIV-associated tuberculosis is increasing worldwide, especially in developing countries. HIV infected patients rapidly develop clinically significant disease, respond poorly to complete treatment and present with extrapulmonary tuberculosis. Although a relative increase of genital tuberculosis would be expected, this has not been reported. Probably, tuberculous systemic disease is diagnosed earlier, before genital tuberculosis occur. The present study is a report of case of a young African female patient, who was admitted with symptoms of acute pelvic inflammatory disease due to genital tuberculosis and proved to be HIV infected. The patient was managed by intravenous antibiotic administration, but since no clinical or laboratory improvement was achieved, a laparotomy and salpingooophorectomy was performed. Histopathology revealed tuberculosis and after that the patient proved to be HIV infected. Further investigation did not reveal pulmonary or other extragenital manifestation of tuberculosis. The only manifestation of HIV infection and genital tuberculosis was the symptoms of an acute pelvic inflammatory disease, which is extremely rare.


Assuntos
Infecções por HIV/complicações , Tuberculose dos Genitais Femininos/complicações , Adulto , Antibacterianos/uso terapêutico , Tubas Uterinas/cirurgia , Feminino , Humanos , Ovariectomia , Doença Inflamatória Pélvica/microbiologia , Tuberculose dos Genitais Femininos/tratamento farmacológico , Tuberculose dos Genitais Femininos/cirurgia
13.
Eur J Gynaecol Oncol ; 19(4): 389-90, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9744733

RESUMO

Meigs' syndrome includes an ovarian tumor, usually fibroma, associated with hydrothorax and ascites. It is accepted that uterine tumors, like fibromas, can also be associated with ascites and hydrothorax, but this is extremely rare. The mechanism of formation of peritoneal and pleural effusion is not well documented. The most likely pathogenesis ascribes the fluid formation to the filtration of interstitial fluid in the peritoneal through the tumor capsule, and the diffusion to the pleural space through the diaphragm lymphatic vessels at the foramen of Bochdalek. Paraovarian fibromas are also extremely rare neoplasms, probably of paramesonephric origin. It has been hypothesised that they can develop by proliferation of connective tissue cells around the Wolfian remnants. In this article, probably for the first time, a case of paraovarian fibroma with ascites and hydrothorax is presented.


Assuntos
Ascite/diagnóstico , Fibroma/diagnóstico , Hidrotórax/diagnóstico , Síndrome de Meigs/diagnóstico , Ligamento Largo , Feminino , Neoplasias dos Genitais Femininos/diagnóstico , Humanos , Pessoa de Meia-Idade
14.
Clin Exp Obstet Gynecol ; 25(3): 92-3, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9856307

RESUMO

A case of intrauterine infection by human parvovirus B19 (HPV B19) manifested as ascites during pregnancy is presented. Ascites was diagnosed by ultrasound at 27 weeks' gestation. A caesarean section was performed at 37 weeks'. owing to affected mobility of the fetus. A pale, female infant with low haemoglobin and bradycardia was delivered. Polymerace Chain Reaction (PCR) lab tests revealed that the mother and the fetus were infected by HPV B19. The neonate was born with low haemoglobin (Hb = 10 g/dl) and with ascites; it was discharged in good general condition 50 days after delivery.


Assuntos
Anemia/virologia , Ascite/virologia , Infecções por Parvoviridae/congênito , Parvovirus B19 Humano , Anemia/terapia , Ascite/patologia , Ascite/cirurgia , Transfusão de Sangue , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Infecções por Parvoviridae/diagnóstico por imagem , Infecções por Parvoviridae/terapia , Gravidez , Respiração Artificial , Ultrassonografia
18.
Phys Rev B Condens Matter ; 51(21): 15062-15073, 1995 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9978460
20.
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