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1.
Phys Rev Lett ; 131(16): 161802, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925710

RESUMO

We present a new measurement of the positive muon magnetic anomaly, a_{µ}≡(g_{µ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{µ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{µ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{µ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision.

2.
Wilderness Environ Med ; 32(4): 468-473, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34580014

RESUMO

INTRODUCTION: Tree stand-related injuries (TSRI) are more common than firearm-related injuries in hunters. Most previous studies on the topic used trauma databases that only include admitted patients. This study characterizes injury patterns found in nonadmitted and admitted TSRI patients presenting to a level 2 Michigan trauma center. TSRI prevention interventions are also discussed. METHODS: Cases were obtained through a retrospective chart review of the Henry Ford Allegiance Health trauma registry and EPSi cost-accounting database from 2015 to 2019. Keywords searched included fall, hunter, tree, tree stand, treestand, ICD 9 diagnosis (E884.9_Other accidental fall from one level to another), and ICD 10 diagnosis (W14.XXXA_Fall from tree, initial encounter). We analyzed age, sex, body mass index, injury severity score, disposition, alcohol use, injuries sustained, reported height of fall, and narrative of fall. RESULTS: Thirty-three patients were identified. Patient age was 45±13 y (mean±SD). All patients were male. Injury severity score for nonadmitted patients was 2±1 vs 13±11 in admitted patients. Thirty-three percent of cases were nonadmitted; 67% were admitted. The most common injuries sustained were spinal (33%) and lower extremity fractures (15%). The average yearly TSRI case rate was 5.73 per 10,000 hunters in the study area. CONCLUSIONS: Our study found that spinal and lower extremity fractures were the most common injuries sustained. One-third of our patients were nonadmitted and therefore not included in the Henry Ford Allegiance Health trauma registry. Some nonadmitted patients had significant injuries requiring specialist consultation, orthopedic braces, or outpatient surgery.


Assuntos
Centros de Traumatologia , Árvores , Acidentes por Quedas , Humanos , Escala de Gravidade do Ferimento , Michigan/epidemiologia , Estudos Retrospectivos
3.
Phys Rev Lett ; 126(14): 141801, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891447

RESUMO

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{µ}≡(g_{µ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{µ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both µ^{+} and µ^{-}, the new experimental average of a_{µ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

5.
World J Emerg Surg ; 11: 25, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27307785

RESUMO

Acute calculus cholecystitis is a very common disease with several area of uncertainty. The World Society of Emergency Surgery developed extensive guidelines in order to cover grey areas. The diagnostic criteria, the antimicrobial therapy, the evaluation of associated common bile duct stones, the identification of "high risk" patients, the surgical timing, the type of surgery, and the alternatives to surgery are discussed. Moreover the algorithm is proposed: as soon as diagnosis is made and after the evaluation of choledocholitiasis risk, laparoscopic cholecystectomy should be offered to all patients exception of those with high risk of morbidity or mortality. These Guidelines must be considered as an adjunctive tool for decision but they are not substitute of the clinical judgement for the individual patient.

6.
Dis Esophagus ; 26(3): 263-71, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23551569

RESUMO

The majority of esophagectomies in Western parts of the world are performed by a transthoracic approach reflecting the prevalence of adenocarcinoma of the lower esophagus or esophagogastric junction. Minimally invasive esophagectomy (MIE) has been reported in a variety of formats, but there are no series that directly compare totally minimally invasive thoracolaparoscopic 2 stage esophagectomy (MIE-2) with open Ivor Lewis (IVL). A prospective single-center cohort study of patients undergoing elective MIE-2 or IVL between January 2005 and November 2010 was performed. Short-term clinicopathologic outcomes were recorded using validated systems. One hundred and six patients (median age 66, range 36-85, 88 M : 18 F) underwent two-stage esophagectomy (53 MIE-2 and 53 IVL). Patient demographics (age, sex, body mass index, American Society of Anesthesiologists grade, tumor characteristics, neoadjuvant chemotherapy, and TNM stage) were comparable between the two groups. Outcomes for MIE-2 and IVL were comparable for anastomotic leak rates (5 [9%] vs. 2 [4%], P= 0.241), resection margin clearance (R0) (43 [81%] vs. 38 [72%], P= 0.253), median lymph node yield (19 vs. 18, P= 0.584), and median length of stay (12 [range 7-91] vs. 12 [range 7-101] days), respectively. Blood loss was significantly less for MIE-2 compared with IVL (median 300 [range 0-1250] mL vs. 400 [range 0-3000] mL, respectively, P= 0.021). MIE-2 in this series of selected patients supports its efficacy, when performed by an experienced minimally invasive surgical team. A well-designed multicenter trial addressing clinical effectiveness is now required.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Anastomótica/etiologia , Perda Sanguínea Cirúrgica , Quimioterapia Adjuvante , Estudos de Coortes , Feminino , Seguimentos , Humanos , Laparoscopia/métodos , Laparotomia/métodos , Tempo de Internação , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Duração da Cirurgia , Complicações Pós-Operatórias , Estudos Prospectivos , Toracoscopia/métodos , Toracotomia/métodos , Resultado do Tratamento
7.
Eur Phys J C Part Fields ; 72(7): 2076, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-25814843

RESUMO

A search is made for charged Higgs bosons predicted by Two-Higgs-Doublet extensions of the Standard Model (2HDM) using electron-positron collision data collected by the OPAL experiment at [Formula: see text], corresponding to an integrated luminosity of approximately 600 pb-1. Charged Higgs bosons are assumed to be pair-produced and to decay into [Formula: see text], τντ or AW±. No signal is observed. Model-independent limits on the charged Higgs-boson production cross section are derived by combining these results with previous searches at lower energies. Under the assumption [Formula: see text], motivated by general 2HDM type II models, excluded areas on the [Formula: see text] plane are presented and charged Higgs bosons are excluded up to a mass of 76.3 GeV at 95 % confidence level, independent of the branching ratio BR(H±â†’τντ ). A scan of the 2HDM type I model parameter space is performed and limits on the Higgs-boson masses [Formula: see text] and mA are presented for different choices of tanß.

8.
Obes Surg ; 17(6): 742-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17879572

RESUMO

BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (LRYGBP) can be technically challenging. It is imperative that patient morbidity and mortality are minimized while teams are on the learning curve for this procedure. METHODS: This retrospective study evaluated the peri-operative risk of LRYGBP utilizing a two-consultant surgeon approach in a newly established bariatric service. 100 consecutive patients undergoing LRYGBP were included. Two consultants participated in each procedure. RESULTS: Median operative duration was 113 minutes (range 80-240) and fell with increasing experience [127 minutes (range 90-240) in cases 1-50 and 105 minutes (range 80-210) in cases 51-100; P=0.009]. Multivariate analysis found operation time correlated only with number of procedures performed (P<0.001). There were no conversions to laparotomy. Intra-operatively, 2 patients had hand-assisted completion of the jejuno-jejunostomy, and 2 underwent laparoscopic revision of the reconstruction. Postoperative complications were observed in 8 patients on the operative admission. Median stay was 4 days (range 3-7). 4 patients required readmission. There was no mortality. Percentage of excess BMI loss was 47%, 53% and 70% at 3, 6 and 12 months respectively. CONCLUSION: A learning curve for LRYGBP is evidenced in this series by reduction in operative time with increasing experience. Complication rates in line with large published series can be achieved by adopting a two-surgeon approach, which we propose as a safe method to adopt in the development of new bariatric services.


Assuntos
Derivação Gástrica/métodos , Laparoscopia , Obesidade Mórbida/cirurgia , Encaminhamento e Consulta , Adulto , Competência Clínica , Feminino , Seguimentos , Derivação Gástrica/educação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
9.
Ann Clin Biochem ; 42(Pt 3): 196-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15949154

RESUMO

BACKGROUND: Thrombocytosis is one of several pre-analytical factors which contribute to spuriously high serum potassium concentrations, yet there is little published data to guide analysts in the selection of a specific platelet count threshold above which serum potassium results become unreliable. We have studied the sensitivity and specificity of blood platelet count as a predictor of false elevations in potassium. METHODS: Paired serum and plasma potassium measurements together with full blood count were performed for 300 patients. All samples were stored at room temperature and analysed within 4 h of collection. The difference between serum and plasma potassium was plotted against blood platelet count. RESULTS: When the difference (serum-plasma) in potassium concentration was plotted against platelet count, there was a direct linear relationship. Blood platelet counts of >500 x 10(9)/L will detect elevations in serum relative to plasma potassium of >0.5 mmol/L, with a sensitivity of 71% and a specificity of 89%. CONCLUSION: It is recommended that where blood platelet count is above 500 x 10(9)/L, potassium measurements should be repeated using lithium heparin plasma. When serum potassium results of >5.4 mmol/L are obtained, it is our policy to check the platelet count if a sample is available before reporting results. If available and above 500 x 10(9)/L, potassium results are withheld and plasma requested.


Assuntos
Contagem de Plaquetas , Potássio/sangue , Níveis Máximos Permitidos , Trombocitose/sangue , Adulto , Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Estudos de Casos e Controles , Humanos , Valores de Referência , Análise de Regressão , Sensibilidade e Especificidade
10.
Water Sci Technol ; 50(1): 105-10, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15318494

RESUMO

A project was designed by Umgeni Water (funded by the Water Research Commission of South Africa) to monitor the implementation of water reticulation in Vulindlela and evaluate the Water Supply Scheme from a community and environmental health perspective. The findings would hopefully contribute toward the development of criteria for Health Impact Assessment on Water Reticulation Projects. One objective of this study was to evaluate the usefulness of diarrhoeal disease as opposed to other health indicators for water-associated diseases. The innovative methodology followed in the study, a "stepped wedge design", compared four discrete areas of water reticulation implementation in Vulindlela over a 15-month period. Five surveys, including a baseline and four follow-ups at each household, were carried out. Analysis (microbiological, chemical) was carried out of samples from the household drinking water and from the source of the water. Each survey included health questionnaires, the respondent being the head of the household in each case. Overall, there was no direct correlation proved between water quality and diarrhoea per se. However, there was a marked decrease in diarrhoea with the introduction of the new water supply. There was definite correlation between hygiene behaviours and diarrhoea. Diarrhoea would seem to be the health impact associated with water, of choice.


Assuntos
Diarreia/etiologia , Saúde Pública , Purificação da Água , Diarreia/epidemiologia , Diarreia/prevenção & controle , Monitoramento Ambiental , Monitoramento Epidemiológico , Comportamentos Relacionados com a Saúde , Humanos , Higiene , População Rural , África do Sul
11.
J Inherit Metab Dis ; 27(2): 145-55, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15159645

RESUMO

Women with phenylketonuria (PKU) must follow a strict low-phenylalanine diet during pregnancy in order to protect the fetus from the deleterious effects of high maternal blood phenylalanine. The Resource Mothers Study of Maternal PKU was undertaken to determine whether a home visitation programme was effective in helping women with PKU attain blood phenylalanine control earlier during pregnancy. Resource Mothers were trained to provide social support and practical assistance to women with PKU during pregnancy. Eight metabolic clinics in the United States participated in the study. Women with PKU who were planning pregnancy or already pregnant were enrolled in the study and were treated with a low-phenylalanine diet aimed at controlling blood phenylalanine to 120-360 micromol/L. They were randomly assigned to receive the services of a Resource Mother (RM group) or to a control group. Fifty women were enrolled, and accounted for 44 pregnancies which resulted in 28 live births, and 6 spontaneous abortions. Ten women are currently pregnant and another 6 have not become pregnant. Fifty-six percent of enrolled women began the diet prior to becoming pregnant. Fifty-three percent of women in the Resource Mother group were in metabolic control by 10 weeks gestation as compared to 39% in the control group. In addition, women who began diet after pregnancy and had a Resource Mother attained metabolic control earlier (mean gestational age of 22.4 weeks in the RM group vs 29.8 weeks in the control group). There was no difference in birth measurement z -scores of offspring born to women in the RM group compared to controls. All but 4 women rated themselves as feeling worse about the diet at the end of pregnancy than at the beginning, and few women in either group remained on diet after delivery.


Assuntos
Doenças Fetais/prevenção & controle , Grupo Associado , Fenilcetonúrias/dietoterapia , Complicações na Gravidez/dietoterapia , Cuidado Pré-Natal/organização & administração , Feminino , Idade Gestacional , Humanos , Cooperação do Paciente , Fenilalanina/sangue , Fenilcetonúrias/metabolismo , Fenilcetonúrias/psicologia , Gravidez , Complicações na Gravidez/metabolismo , Complicações na Gravidez/psicologia , Resultado da Gravidez , Avaliação de Programas e Projetos de Saúde , Apoio Social
14.
Phys Med Biol ; 46(2): 487-98, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11229728

RESUMO

Radiation dose distributions arising from intrahepatic arterial infusion of 90Y microspheres have been investigated. Tissue samples from normal liver, the tumour periphery and tumour centre were taken from a patient following infusion of 3 GBq of 32 microm diameter resin microspheres labelled with 90Y as treatment for an 80 mm diameter metastatic liver tumour. The measured microsphere distributions in three dimensions were used to calculate radiation dose patterns. Although microspheres concentrated in the tumour periphery, heterogeneous doses were delivered to all tissues. Within the tumour periphery average doses ranged from 200 Gy to 600 Gy with minimum doses between 70 Gy and 190 Gy. The average and minimum doses for the tumour centre sample were 6.8 Gy and 3.7 Gy respectively. In the normal liver sample the average dose was 8.9 Gy with a minimum dose of 5 Gy. Less than 1% of the normal liver tissue volume received more than 30 Gy, the level above which complications have resulted for whole liver exposure using external beam radiotherapy. These calculations suggest that preferential deposition of microspheres in the well-vascularized periphery of large tumours will lead to a high proportion of the tumour volume receiving a therapeutic dose, with most of the normal liver tissue being spared substantial damage.


Assuntos
Neoplasias Hepáticas/radioterapia , Radioisótopos de Ítrio/uso terapêutico , Fenômenos Biofísicos , Biofísica , Artéria Hepática , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/secundário , Microesferas , Radiometria/métodos , Radiometria/estatística & dados numéricos , Planejamento da Radioterapia Assistida por Computador , Radioisótopos de Ítrio/administração & dosagem
15.
Cornea ; 19(3): 292-6, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10832686

RESUMO

PURPOSE: Accurate and reliable evaluation techniques are essential for clinical and epidemiologic studies. This survey of corneal specialists was designed to lay a foundation for the further development of methods for evaluating and staging pterygium. METHODS: In a self-administered, mailed questionnaire, 213 corneal specialists rated the importance of nine symptoms, nine signs, and nine clinical tests for the severity of primary pterygium. Severity was defined as the present need for surgical intervention. RESULTS: The most important factors for determining primary pterygium severity were the extent of encroachment onto the cornea, decreased visual acuity, restricted ocular motility, and increased rate of growth. Many patient symptoms were rated as moderately to highly important. The questionnaire was shown to have good response reliability by test-retest comparisons. Cronbach's alpha was 0.89, which indicates very good internal consistency reliability. CONCLUSION: The survey identifies the priorities of experts in determining the severity of pterygium. More precise and clearly defined evaluation methods will enhance future clinical and epidemiologic studies of pterygium. The ranked list of pterygium signs, symptoms, and tests can serve as a guide for developing pterygium evaluation methods in the future. There is a need for a method that accurately and precisely quantifies the distance of pterygium encroachment onto the cornea and the pterygium progression rate. Furthermore, there is a need for an assessment of patient symptoms.


Assuntos
Inquéritos Epidemiológicos , Oftalmologia/estatística & dados numéricos , Padrões de Prática Médica , Pterígio/diagnóstico , Humanos , Pterígio/classificação , Pterígio/cirurgia , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Inquéritos e Questionários
16.
Phys Med Biol ; 45(4): 1023-33, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10795989

RESUMO

The microscopic distribution of microspheres in human liver following hepatic infusion of 32 microm diameter resin microspheres labelled with 90Y as treatment for an 80 millimetre diameter liver cancer has been investigated. Microspheres were found to deposit inhomogeneously in tissues, preferentially lodging in a region approximately 6 mm wide around the periphery of the tumour. A relative concentration of microspheres of 50 to 70 times that of normal hepatic parenchyma and 65 to 94 times that in the tumour centre was measured in this region. The deposition of spheres in the tumour periphery was not uniform, and cluster analysis showed that the spheres could be classified into clusters. The number of microspheres in a cluster was skewed towards low numbers and cluster sizes varied from 20 to 1500 microm. The observed deposition patterns indicate that the vascular tumour periphery will receive much greater radiation doses from radioactive microspheres than both normal tissue and the avascular tumour centre.


Assuntos
Neoplasias Hepáticas/radioterapia , Fígado/metabolismo , Radioisótopos de Ítrio/uso terapêutico , Artérias/metabolismo , Artérias/efeitos da radiação , Análise por Conglomerados , Neoplasias do Colo/patologia , Humanos , Fígado/irrigação sanguínea , Fígado/efeitos da radiação , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Microesferas , Distribuição Tecidual , Radioisótopos de Ítrio/metabolismo
17.
Optometry ; 71(7): 449-53, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15326898

RESUMO

BACKGROUND: The primary purpose of public policy requiring vision testing for driver license renewal is to identify individuals with functional vision impairments and, when necessary, to restrict their driving. This is based on the presumption that poor vision is causally related to poor driving and traffic crashes. METHODS: The AOA Environmental and Occupational Vision Committee performed a synthesis of relevant empirical literature on policy-based research and developed potential options for enhancing traffic safety. RESULTS: Presently, some states require vision testing for driver's license renewal and some do not. Regional and nationwide studies report that vision-related license renewal policies are associated with enhanced traffic safety. However, contemporary vision screening tests may be of limited value in identifying individuals with functional vision impairments. CONCLUSION: The most cost-effective and valid method for identifying, treating and counseling visually impaired drivers is to require a comprehensive eye examination as a condition for driver license renewal for those with a high prevalence or high probability of vision impairment.


Assuntos
Exame para Habilitação de Motoristas , Condução de Veículo , Política de Saúde , Optometria/normas , Testes Visuais/normas , Visão Ocular/fisiologia , Acidentes de Trânsito/prevenção & controle , Envelhecimento/fisiologia , Guias como Assunto , Humanos , Estados Unidos , Transtornos da Visão/diagnóstico
18.
Ann Surg ; 228(1): 29-34, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9671063

RESUMO

OBJECTIVE: To establish a simple, reproducible, and safe technique of laparoscopic common bile duct exploration (CBDE) with high clearance rates and low morbidity and mortality rates. SUMMARY BACKGROUND DATA: For most general surgeons, laparoscopic CBDE appears an unduly complex and demanding procedure. Since the introduction of laparoscopic cholecystectomy, many surgeons use endoscopic cholangiography (ERC) and endoscopic sphincterotomy as their only option in treating bile duct stones. ERC is more specific if used after surgery, but it carries an appreciable morbidity rate and has the disadvantage of requiring a second procedure to deal with bile duct stones. To this end, various methods of laparoscopic CBDE have been developed. METHODS: Between August 1991 and February 1997, 300 consecutive unselected patients underwent laparoscopic CBDE. RESULTS: Of 300 laparoscopic CBDE procedures, 173 (58%) were managed using a transcystic approach and 127 (42%) with choledochotomy. Successful laparoscopic stone clearance was achieved in 271 (90%). Of the 29 (10%) patients not cleared laparoscopically, 10 had an elective postsurgical ERC, 12 were converted to an open procedure early in the series, and 7 had unexpected retained stones. There was one death (mortality rate 0.3%) and major morbidity occurred in 22 patients (7%). The last 100 procedures were performed from July 1995 to February 1997, and stone clearance was unsuccessful in only two patients. CONCLUSIONS: Laparoscopic transcystic basket extraction of common duct stones under fluoroscopic guidance is a relatively quick, successful, and safe technique. Choledochotomy, when required, is associated with a higher morbidity rate, particularly with T-tube insertion, and the authors advocate primary bile duct closure with or without insertion of a biliary stent as a more satisfactory technique for both surgeon and patient. Most patients with gallbladder and common duct calculi should expect a curative one-stage laparoscopic procedure without the need for external biliary drainage or ERC.


Assuntos
Ducto Colédoco/cirurgia , Cálculos Biliares/cirurgia , Laparoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Reoperação , Estudos Retrospectivos , Stents
19.
Optom Vis Sci ; 75(5): 342-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9624699

RESUMO

PURPOSE: This study investigates features of visual acuity chart design and acuity testing scoring methods which affect the validity and repeatability of visual acuity measurements. METHODS: Visual acuity was measured using the Sloan and British Standard letter series, and Landolt rings. Identifiability of the different letters as a function of size was estimated, and expressed in the form of frequency-of-seeing curves. These functions were then used to simulate acuity measurements with a variety of chart designs and scoring criteria. RESULTS: Systematic relationships exist between chart design parameters and acuity score, and acuity score repeatability. In particular, an important feature of a chart, that largely determines the repeatability of visual acuity measurement, is the amount of size change attributed to each letter. The methods used to score visual acuity performance also affect repeatability. CONCLUSIONS: It is possible to evaluate acuity score validity and repeatability using the statistical principles discussed here.


Assuntos
Testes Visuais/instrumentação , Acuidade Visual , Adulto , Humanos , Leitura , Reprodutibilidade dos Testes , Testes Visuais/métodos , Testes Visuais/normas
20.
Aust N Z J Surg ; 68(3): 213-5, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9563453

RESUMO

Surgical management of bleeding duodenal ulcer has traditionally included a procedure to reduce gastric acid production to enable ulcer healing and reduce the likelihood of rebleeding. The availability of intravenous proton pump inhibitors in the peri-operative period may promote rapid ulcer healing and as a component of anti-Helicobacter eradication therapy greatly reduces the incidence of ulcer recurrence. Using this approach, six patients with actively bleeding duodenal ulcer underwent laparoscopic duodenotomy and attempted suturing of the bleeding site. One patient required conversion to open surgery and subsequently re-bled at 60 h, necessitating a partial (Billroth II) gastrectomy. In the remaining five patients suture control of bleeding and luminal closure were completed laparoscopically without complications. Laparoscopic repair of acutely bleeding duodenal ulcers is technically feasible and had a low complication rate in this small series.


Assuntos
Úlcera Duodenal/cirurgia , Laparoscopia/métodos , Úlcera Péptica Hemorrágica/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Duodeno/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos
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