Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081262

RESUMO

We describe the first implementation of a Josephson Traveling Wave Parametric Amplifier (JTWPA) in an axion dark matter search. The operation of the JTWPA for a period of about two weeks achieved sensitivity to axion-like particle dark matter with axion-photon couplings above 10-13 Ge V-1 over a narrow range of axion masses centered around 19.84 µeV by tuning the resonant frequency of the cavity over the frequency range of 4796.7-4799.5 MHz. The JTWPA was operated in the insert of the axion dark matter experiment as part of an independent receiver chain that was attached to a 0.56-l cavity. The ability of the JTWPA to deliver high gain over a wide (3 GHz) bandwidth has engendered interest from those aiming to perform broadband axion searches, a longstanding goal in this field.

2.
Phys Rev Lett ; 131(10): 101002, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739367

RESUMO

We report the first result of a direct search for a cosmic axion background (CaB)-a relativistic background of axions that is not dark matter-performed with the axion haloscope, the Axion Dark Matter eXperiment (ADMX). Conventional haloscope analyses search for a signal with a narrow bandwidth, as predicted for dark matter, whereas the CaB will be broad. We introduce a novel analysis strategy, which searches for a CaB induced daily modulation in the power measured by the haloscope. Using this, we repurpose data collected to search for dark matter to set a limit on the axion photon coupling of a CaB originating from dark matter cascade decay via a mediator in the 800-995 MHz frequency range. We find that the present sensitivity is limited by fluctuations in the cavity readout as the instrument scans across dark matter masses. Nevertheless, we suggest that these challenges can be surmounted using superconducting qubits as single photon counters, and allow ADMX to operate as a telescope searching for axions emerging from the decay of dark matter. The daily modulation analysis technique we introduce can be deployed for various broadband rf signals, such as other forms of a CaB or even high-frequency gravitational waves.

3.
Phys Rev Lett ; 127(8): 081802, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34477436

RESUMO

The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) achieved efficient detection of very small recoil energies in its germanium target, resulting in sensitivity to lightly ionizing particles (LIPs) in a previously unexplored region of charge, mass, and velocity parameter space. We report first direct-detection limits calculated using the optimum interval method on the vertical intensity of cosmogenically produced LIPs with an electric charge smaller than e/(3×10^{5}), as well as the strongest limits for charge ≤e/160, with a minimum vertical intensity of 1.36×10^{-7} cm^{-2} s^{-1} sr^{-1} at charge e/160. These results apply over a wide range of LIP masses (5 MeV/c^{2} to 100 TeV/c^{2}) and cover a wide range of ßγ values (0.1-10^{6}), thus excluding nonrelativistic LIPs with ßγ as small as 0.1 for the first time.

4.
Phys Rev Lett ; 127(6): 061801, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34420312

RESUMO

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst) eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140 MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

5.
Phys Rev Lett ; 127(26): 261803, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029490

RESUMO

We report the results from a haloscope search for axion dark matter in the 3.3-4.2 µeV mass range. This search excludes the axion-photon coupling predicted by one of the benchmark models of "invisible" axion dark matter, the Kim-Shifman-Vainshtein-Zakharov model. This sensitivity is achieved using a large-volume cavity, a superconducting magnet, an ultra low noise Josephson parametric amplifier, and sub-Kelvin temperatures. The validity of our detection procedure is ensured by injecting and detecting blind synthetic axion signals.

6.
Arch Dis Child ; 96(12): 1097-102, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21937486

RESUMO

OBJECTIVE: To quantify the effects of a thermostatic control system in social (public) housing on the prevalence of dangerous (>60°C) water temperatures and on fuel consumption. DESIGN: Pair-matched double-blind cluster randomised controlled trial. SETTING: Social housing in a deprived inner-London borough. PARTICIPANTS: 150 households recruited as clusters from 22 social housing estates. Four small estates were combined into two clusters (resulting in a total of 10 pairs of clusters). INTERVENTION: Social housing estate boiler houses were randomised to a thermostatic control sterilisation programme (heating water to 65°C during 00:00-06:00 h and to 50°C from 06:00 to 00:00 h daily) or to standard control (constant temperature 65°C). MAIN OUTCOME MEASURES: Water temperature over 60°C ('dangerous') after running taps for 1 min and daily fuel consumption (cubic feet of gas). RESULTS: 10 clusters (80 households) were allocated to the sterilisation programme and 10 clusters (70 households) to control, of which 73 and 67 households, respectively, were analysed. Prevalence of dangerous (>60°C) hot water temperatures at 1 min was significantly reduced with the sterilisation programme (mean of cluster prevalence 1% in sterilisation programme group vs 34% in control group; absolute difference 33%, 95% CI 12% to 54%; p=0.006). Prevalence of high (>55°C) hot water temperatures at 1 min was significantly reduced (31% sterilisation vs 59% control; absolute difference 28%, 95% CI 9% to 47%; p=0.009). Gas consumption per day reduced more in the control group than in the sterilisation programme group, although not statistically significantly (p=0.125). CONCLUSIONS: The thermostatic control with daily sterilisation was effective in capping hot water temperatures and therefore reduced scald risk. Although expected to save energy, fuel consumption was increased relative to the control group. Trial registration ClinicalTrials.gov ID: NCT00874692.


Assuntos
Queimaduras/prevenção & controle , Calefação/métodos , Temperatura Alta/efeitos adversos , Doença dos Legionários/transmissão , Habitação Popular , Queimaduras/etiologia , Criança , Pré-Escolar , Método Duplo-Cego , Fontes de Energia Elétrica , Estudos de Viabilidade , Humanos , Doença dos Legionários/prevenção & controle , Londres , Áreas de Pobreza , Esterilização/métodos , Temperatura , Microbiologia da Água
7.
J Dent Hyg ; 78(3): 6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-16201062

RESUMO

Dental hygienists help their clients develop health promoting behaviors, by providing essential information about general health, and oral health in particular. Individual health practices such as oral self-care are based on personal choices. The guiding principles found in health behavior models provide useful methods to the oral health care providers in promoting effective individual client behaviors. Theories provide explanations about observable facts in a systematic manner. Research regarding health behavior has explored the effectiveness and applicability of various health models in oral health behavior modification. The Health Belief Model, Transtheoretical Model and Stages of Change, Theory of Reasoned Action, Self-Efficacy, Locus of Control, and Sense of Coherence are examples of models that focus on individuals assuming responsibility for their own health. Understanding the strengths of each and their applicability to health behaviors is critical for oral health care providers who work with patients to adopt methods and modify behaviors that contribute to good oral health. This paper describes health behavior models that have been applied to oral health education, presents a critical analysis of the effectiveness of each model in oral health education, and provides examples of application to oral health education.


Assuntos
Comportamentos Relacionados com a Saúde , Educação em Saúde Bucal , Modelos Psicológicos , Higiene Bucal/psicologia , Terapia Comportamental/métodos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Controle Interno-Externo , Educação de Pacientes como Assunto , Participação do Paciente , Teoria Psicológica , Autoeficácia
9.
Magn Reson Imaging Clin N Am ; 8(2): 225-41, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10819913

RESUMO

Low-field strength, dedicated extremity MR imaging systems can provide clinically effective MR images at substantially lower costs, compared with high-field strength, whole-body MR imaging machines. Dedicated extremity units also reduce risks of patient safety and claustrophobia. The diagnostic performance of presently existing extremity MR scanners rivals that of high-field strength units. Focusing on the imaging of the knee joint, this article discusses issues of technique, imaging protocol, clinical roles, and economics, and reviews diagnostic efficacy studies.


Assuntos
Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Tecido Adiposo , Artefatos , Custos e Análise de Custo , Gadolínio , Humanos , Artropatias/patologia , Imageamento por Ressonância Magnética/economia , Imageamento por Ressonância Magnética/instrumentação
10.
Am J Surg ; 178(2): 166-72, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10487272

RESUMO

BACKGROUND: The purpose of the study was to determine whether preoperative treatment plans for patients with lower extremity ischemia can be made with electrocardiography (EKG)-triggered two-dimensional (2D) time-of-flight (TOF) magnetic resonance angiography (MRA) as accurately as digital subtraction angiography (DSA). METHODS: Forty patients were prospectively evaluated with the combination of EKG-triggered 2D TOF MRA, DSA, and pulse volume recordings. Blinded reviewers graded arterial segments for disease severity. Accuracy of separate MRA- and DSA-based treatment plans was compared with the procedures performed based on all available information. RESULTS: There was an 86% exact match between MRA- and DSA-based plans (92% MRA and 94% DSA accuracy). The MRA-based plan accurately predicted 90% of suprainguinal and 95% of infrainguinal procedures, whereas the DSA-based plan accurately predicted 100% of suprainguinal and 85% of infrainguinal procedures. Two-year primary patency was 83% for all procedures. Radiologists' review of disease severity resulted in a mean exact correlation between studies of 81% (kappa = 0.64). The agreement between radiologists interpreting the MRA was 84% (kappa = 0.7) compared with 82% (kappa = 0.66) for the DSA. CONCLUSIONS: MRA- and DSA-based preoperative management plans were of comparable efficacy. Significant interobserver variability was seen with the interpretations of both preoperative studies. EKG-triggered 2D TOF MRA can be used to plan arterial reconstructions; however, all patients require arterial pressure measurements prior to suprainguinal repair and confirmatory intraoperative angiography during infrainguinal revascularization.


Assuntos
Angiografia Digital , Arteriopatias Oclusivas/diagnóstico , Eletrocardiografia , Perna (Membro)/irrigação sanguínea , Angiografia por Ressonância Magnética/métodos , Planejamento de Assistência ao Paciente , Idoso , Arteriopatias Oclusivas/classificação , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/cirurgia , Pressão Sanguínea/fisiologia , Seguimentos , Previsões , Humanos , Processamento de Imagem Assistida por Computador/métodos , Canal Inguinal/irrigação sanguínea , Cuidados Intraoperatórios , Isquemia/classificação , Isquemia/diagnóstico , Isquemia/diagnóstico por imagem , Isquemia/cirurgia , Masculino , Variações Dependentes do Observador , Estudos Prospectivos , Pulso Arterial , Radiografia Intervencionista , Sensibilidade e Especificidade , Método Simples-Cego , Grau de Desobstrução Vascular
11.
AJR Am J Roentgenol ; 172(6): 1561-5, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10350289

RESUMO

OBJECTIVE: To our knowledge, few studies exist on the importance of the oblique view when radiography of the distal extremities is performed after acute trauma. Our prospective study aimed to determine whether the oblique view uniquely revealed abnormalities or clarified findings when it was obtained along with routine frontal and lateral radiographs. SUBJECTS AND METHODS: We prospectively interpreted 1461 consecutive radiographic examinations of the distal extremities in patients presenting with acute trauma to four family medicine clinics. The anatomic sites radiographed included the ankle, foot, toe, wrist, hand, finger, and thumb. Each study was interpreted and given a diagnostic certainty score using the lateral and posteroanterior or anteroposterior views only and then scored again with the oblique view added. RESULTS: The examinations included 421 with abnormal findings, 34 with equivocal findings, and 1006 with normal findings. The addition of the oblique view changed the interpretation in 70 (4.8%) of the 1461 examinations. Of these changed interpretations, 39 were changed from equivocal to either positive or negative, three from positive to negative, and 28 from negative to positive. Addition of the oblique view increased diagnostic confidence: The percentage of examinations scored as having probably normal, equivocal, and probably abnormal findings decreased from 13.9% with two views to 8.4% with three views (p < .0001). The oblique view was equally valuable in the ankle, foot, toe, wrist, hand, finger, and thumb. CONCLUSION: In the distal extremities, the oblique view uniquely reveals abnormalities and increases the confidence of the final radiographic diagnosis when the oblique view is interpreted along with frontal and lateral radiographs.


Assuntos
Traumatismos do Braço/diagnóstico por imagem , Traumatismos da Perna/diagnóstico por imagem , Adolescente , Adulto , Braço/diagnóstico por imagem , Distribuição de Qui-Quadrado , Feminino , Humanos , Perna (Membro)/diagnóstico por imagem , Masculino , Variações Dependentes do Observador , Estudos Prospectivos , Radiografia/métodos , Radiografia/estatística & dados numéricos , Estudos Retrospectivos
12.
Skeletal Radiol ; 28(12): 685-90, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10653363

RESUMO

OBJECTIVE: To compare the sensitivity, specificity, and accuracy of fat-suppressed fast spin-echo (FSE) mid-TE (TE[effective]=34) images with fat-suppressed FSE T2-weighted images for the diagnosis of labral abnormalities. DESIGN AND PATIENTS: The study included 27 consecutive patients who had axial fat-suppressed FSE T2-weighted and fat-suppressed FSE mid-TE MR images, and had labral abnormalities diagnosed at arthroscopy. The acquisition time was about 5 min for each sequence, but the mid-TE sequence allowed a higher spatial resolution than the T2-weighted images (256x256 versus 256x192). Twenty-eight age-matched patients with arthroscopically normal labra were included as a control group. The labrum was graded on the MR images as normal or abnormal separately by two musculoskeletal radiologists who were masked to the history and arthroscopic results. The surgical findings were used as the gold standard for calculating the sensitivity, specificity, and accuracy for interpreting the correct location of a labral abnormality. The sensitivity, specificity, and accuracy for the two sequences were compared with a McNemar test, and significance defined as P<0.05. RESULTS: For observer 1, the sensitivity for labral abnormalities was 0.59 on the T2-weighted images, and 0.78 on the mid-TE images (P=0.12). The specificity was 0.54 for the T2-weighted, and 0.64 for the mid-TE images (P=0.51). The accuracy was 0.56 for the T2-weighted, and 0.71 for the mid- TE images (P=0.08). For observer 2, the sensitivity/specificity/accuracy was 0.67/0.93/0.80 for the T2-weighted, and 0.70/0.86/0.78 for the mid-TE images (all P>0.5). CONCLUSION: In this small study there is no statistically significant difference for demonstrating labral abnormalities between FSE T2-weighted images, and higher-resolution fat-suppressed FSE mid-TE (TE[effective]=34) images obtained with a similar acquisition time. Although there was a general trend toward higher sensitivity and accuracy with the mid-TE sequence, particularly for one of the two observers, a larger study is needed to determine whether this is the preferred single axial pulse sequence for conventional MR imaging of the labrum.


Assuntos
Imageamento por Ressonância Magnética/métodos , Lesões do Ombro , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Articulação do Ombro/anatomia & histologia , Articulação do Ombro/patologia , Ferimentos e Lesões/diagnóstico
13.
AJR Am J Roentgenol ; 168(4): 919-23, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9124140

RESUMO

OBJECTIVE: The purpose of this study was to use MR imaging to evaluate the prevalence and extent of rotator cuff tears in paraplegic patients, who are at increased risk for impingement caused by overuse. MATERIALS AND METHODS: Sixty-four MR examinations of the shoulder were evaluated for partial or full-thickness rotator cuff tears and for single or multiple rotator cuff tendon tears. Thirty-seven MR studies were from paraplegic subjects (26 symptomatic, 11 asymptomatic), and 27 MR studies were from able-bodied subjects (17 symptomatic, 10 asymptomatic). RESULTS: Among subjects who were symptomatic and paraplegic, 73% of shoulders imaged showed evidence of rotator cuff tear on MR images compared with 59% of shoulders in able-bodied symptomatic subjects. Of all subjects with paraplegia, 57% of shoulders imaged showed rotator cuff tears. Among all paraplegic subjects, prevalence and severity of tears correlated positively with age and duration of spinal cord injury. Tears that involved the posterior portion of the rotator cuff were revealed on MR images in 74% of the paraplegic subjects compared with 50% of the able-bodied subjects. CONCLUSION: MR imaging revealed a high percentage and degree of severity of rotator cuff tears in individuals with paraplegia and thus proved useful in evaluating shoulders in these patients.


Assuntos
Imageamento por Ressonância Magnética , Paraplegia/complicações , Lesões do Manguito Rotador , Adulto , Idoso , Transtornos Traumáticos Cumulativos/complicações , Transtornos Traumáticos Cumulativos/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Manguito Rotador/patologia , Síndrome de Colisão do Ombro/diagnóstico , Síndrome de Colisão do Ombro/etiologia , Traumatismos dos Tendões/complicações , Traumatismos dos Tendões/diagnóstico
15.
AJR Am J Roentgenol ; 165(3): 605-8, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7645478

RESUMO

OBJECTIVE: Although an association between sonographically detected joint fluid and rotator cuff disease has been reported, the significance of sonographically detected subacromial/subdeltoid bursal effusion has not been studied. We examined a group of patients who had shoulder sonography and surgery to determine the association between bursal and joint effusion and surgically proved tears of the rotator cuff. MATERIALS AND METHODS: We retrospectively reviewed the preoperative shoulder sonography reports of 163 patients for the presence of fluid within the subacromial/subdeltoid bursa or glenohumeral joint. Surgical reports were obtained to determine the status of the rotator cuff. The sonographic reports of 232 asymptomatic shoulders were also reviewed to determine the prevalence of fluid within the subacromial/subdeltoid bursa or the glenohumeral joint. RESULTS: Sixty-seven (41%) of the 163 patients had a joint effusion, bursal fluid, or both. Joint effusion alone was seen in 35 patients. Fourteen of these had a normal rotator cuff at surgery, and 21 had a rotator cuff tear (sensitivity, 22%; specificity, 79%; positive predictive value, 60%). Bursal fluid alone was seen in 10 patients, seven of whom had a rotator cuff tear (sensitivity, 7%; specificity, 96%; positive predictive value, 70%). In 22 patients, fluid was seen in both the bursa and the joint; 21 had surgically proved rotator cuff tears (sensitivity, 22%; specificity, 99%; positive predictive value, 95%). Of the 232 asymptomatic shoulders, 16 (6.9%) had isolated joint effusions, eight (3.4%) had isolated bursal effusions, and four (1.7%) had both joint and bursal effusions. CONCLUSION: The sonographic finding of intraarticular fluid alone (without bursal fluid) has both a low sensitivity and a low specificity for the diagnosis of rotator cuff tears. However, the finding of fluid in the subacromial/subdeltoid bursa, especially when combined with a joint effusion, is highly specific and has a high positive predictive value for associated rotator cuff tears. Sonographically detected fluid in both the joint and the bursa is an uncommon finding in asymptomatic shoulders. The sonographic observation of fluid in the subacromial bursa, either isolated or combined with a joint effusion, should prompt a careful evaluation of the supraspinatus tendon for tear.


Assuntos
Lesões do Manguito Rotador , Articulação do Ombro/diagnóstico por imagem , Líquido Sinovial/diagnóstico por imagem , Acrômio , Adulto , Idoso , Idoso de 80 Anos ou mais , Exsudatos e Transudatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Traumatismos dos Tendões/diagnóstico por imagem , Ultrassonografia
16.
Abdom Imaging ; 19(1): 57-60, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8161906

RESUMO

We prospectively studied 12 patients before and after bone marrow transplantation (BMT) with serial sonography to evaluate gallbladder sludge formation. Patients were studied on four separate occasions to assess the gallbladder for sludge and stones: prior to BMT and conditioning chemoradiation, and on days 3, 13, and 28 after BMT. During two of the sonographic studies, gallbladder volume measurements were made before and after administration of cholecystokinin octapeptide (CCK-OP) and the ejection fraction (EF) was calculated. Medical records were reviewed for symptoms of cholecystitis, narcotic use, and dietary intake. Sludge and/or stones developed in eight of 12 patients (67%), and in four patients sludge was observed by day 3 post-BMT. Ejection fraction was normal (> 50%) pre-BMT in six of the eight patients who developed sludge, and in four of these six post-BMT. Furthermore, five of the eight patients developed sludge and/or stones in the absence of fasting and/or narcotic use. We conclude that gallbladder sludge develops frequently and early in BMT patients and may resolve or progress to stone formation. We did not demonstrate a relationship between impaired contractility and the development of sludge and/or stones, nor did we find a strong association between sludge formation and conditions presumed to cause gallbladder stasis, such as narcotic use and fasting. These findings suggest that other factors apart from impaired gallbladder contractility may play a role in the formation of sludge in the BMT patient.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Doenças da Vesícula Biliar/diagnóstico por imagem , Adulto , Colelitíase/diagnóstico por imagem , Colelitíase/etiologia , Colelitíase/fisiopatologia , Jejum/efeitos adversos , Feminino , Doenças da Vesícula Biliar/etiologia , Doenças da Vesícula Biliar/fisiopatologia , Esvaziamento da Vesícula Biliar , Humanos , Masculino , Pessoa de Meia-Idade , Entorpecentes/efeitos adversos , Estudos Prospectivos , Ultrassonografia
17.
J Dent Educ ; 57(12): 901-12, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8263237

RESUMO

It is well established that many systemic adverse health conditions have manifestations in the oral cavity. The purpose of this paper is to summarize the available scientific evidence that describes the opposite effect, how adverse oral health conditions affect three aspects of daily living: 1) systemic health, 2) quality of life, and 3) economic productivity. Examples of oral health affecting systemic health include rheumatic fever patients who develop infective endocarditis from oral bacteria and organ transplant patients who develop severe complications from oral infections. Both systemic health and quality of life are compromised when edentulousness, xerostomia, soft tissue lesions, or poorly fitting dentures affect eating and food choices. Conditions such as oral clefts, missing teeth, severe malocclusion, or severe caries are associated with feelings of embarrassment, withdrawal, and anxiety. Oral and facial pain from dentures, temporomandibular joint disorders, and oral infections affect social interaction and daily behaviors. The results of oral disorders can be felt not only physically and socially but also economically in our society. Dental disease accounts for many lost work and school days. Lower wage earners and minorities are disproportionately affected. Although there are many studies that evaluate these relationships, most are case reports, cross-sectional studies, or studies restricted to small or unique population groups. Lack of standardized measurements make comparisons across studies difficult. More population-based and longitudinal studies are needed to better understand the nature of these relationships.


Assuntos
Efeitos Psicossociais da Doença , Inquéritos de Saúde Bucal , Nível de Saúde , Doenças da Boca , Qualidade de Vida , Absenteísmo , Idoso , Bacteriemia/etiologia , Criança , Pré-Escolar , Doença Crônica , Eficiência , Endocardite Bacteriana/etiologia , Dor Facial/complicações , Infecção Focal Dentária , Cardiopatias/etiologia , Humanos , Doenças da Boca/complicações , Doenças da Boca/economia , Doenças da Boca/psicologia , Distúrbios Nutricionais/etiologia , Infecções Oportunistas/etiologia , Isolamento Social , Estados Unidos
18.
Am J Gastroenterol ; 88(7): 1044-9, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8317403

RESUMO

With hepatobiliary scintigraphy and sonography, we prospectively studied the occurrence of new hepatobiliary abnormalities in 18 patients before, and from 1 to 103 days after, bone marrow transplantation (BMT). Prior to BMT, all patients had normal hepatic uptake and visualization of the gallbladder by 60 min on scintigraphy, and no sludge, stones, or other abnormalities on sonography. After BMT, 16 patients (89%) developed new scintigraphic and/or sonographic hepatobiliary abnormalities. Fifteen patients had impaired liver uptake of mebrofenin, while 11 developed gallbladder uptake of mebrofenin, while 11 developed gallbladder sludge and/or stones, and 10 had gallbladder nonvisualization at 60 min. Nevertheless, no patient developed clinical or laboratory evidence of acute cholecystitis. New hepatobiliary abnormalities are more common during the first months post-BMT than clinically suspected, probably reflecting the combined effects of hepatotoxic chemoradiation therapy, graft-versus-host disease, and prolonged administration of parenteral alimentation. Evidence of acute cholecystitis is generally not found.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Doenças da Vesícula Biliar/etiologia , Hepatopatias/etiologia , Adulto , Feminino , Vesícula Biliar/diagnóstico por imagem , Doenças da Vesícula Biliar/diagnóstico por imagem , Humanos , Fígado/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia , Ultrassonografia
19.
Am J Obstet Gynecol ; 161(1): 229-33, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2750809

RESUMO

We infused forskolin in 30% ethanol or 30% ethanol systemically in seven chronically catheterized near-term sheep to determine the response of ovine uterine musculature to cyclic adenosine monophosphate stimulation. Maternal and fetal arterial pressure, fetal venous pressure, intrauterine pressure, and uterine electromyogram activity were monitored continuously. Prostaglandin E2 was infused at a delivery rate that caused a minimal 5 mm Hg increase in intrauterine pressure with definite contraction-like pressure spikes and associated uterine electromyogram activity. Forskolin (10 mg in 30% ethanol) or ethanol (vehicle) was then infused for 20 minutes. The prostaglandin E2 challenge was repeated 3 minutes later and again every 30 minutes over a 2 1/2-hour period. Data were analyzed by repeated measures analysis of variance. Infusion of ethanol (n = 2) had no apparent effect on either the intrauterine pressure or the uterine electromyogram response to prostaglandin E2 challenge. Forskolin infusion (n = 5) caused an attenuation of the intrauterine pressure response to prostaglandin E2 for 93 minutes. This effect was greatest 33 minutes after the infusion ended when the integrated pressure signal was 37% of the initial prostaglandin E2 response. The forskolin infusion had no effect on uterine electromyogram response to prostaglandin E2. We conclude that forskolin causes an uncoupling of excitation from contraction in the intact near-term ovine uterus.


Assuntos
Músculo Liso/fisiologia , Contração Uterina , Útero/fisiologia , Animais , Colforsina/farmacologia , Dinoprostona , Eletromiografia , Feminino , Veículos Farmacêuticos , Gravidez , Contração Uterina/efeitos dos fármacos
20.
J Dev Physiol ; 11(1): 25-8, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2529307

RESUMO

Atrial natriuretic factor (ANF) is a potent endogenous vaso-dilator and diuretic peptide of uncertain physiologic relevance. In this study, the effects of ANF on normal and angiotensin II constricted placental, uterine and renal vessels were examined in pregnant sheep. Ewes were equipped with catheters to monitor vascular pressures, infuse drugs and measure blood flow by the microsphere technique. An electromagnetic flow sensor was placed around the middle uterine artery and electromyogram electrodes were attached to the uterus. ANF was administered into a branch of the uterine artery to minimize its systemic effects. The experiment included two protocols. First, blood flows and pressures were measured after a 5-min period of saline infusion into the uterine artery. These measurements were repeated at the end of a 5-min infusion of ANF (6.25 micrograms.min-1) into the uterine artery. During the second protocol, angiotensin II (AII) was infused via the jugular vein at 5 micrograms.min-1 for 10 min and ANF (6.25 micrograms.min-1) was infused through the uterine artery during the second half of the AII infusion. In the absence of AII, ANF lowered blood pressure from 97 +/- 6 to 90 +/- 6 mmHg (P less than 0.05); and placental resistance from 67.8 +/- 11.3 to 57.3 +/- 10.4 mmHg.min.ml-1 per g (P less than 0.01). Uterine resistance did not change.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fator Natriurético Atrial/farmacologia , Rim/irrigação sanguínea , Placenta/irrigação sanguínea , Prenhez , Útero/irrigação sanguínea , Resistência Vascular/efeitos dos fármacos , Vasodilatação , Angiotensina II/farmacologia , Animais , Feminino , Gravidez , Ovinos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...