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1.
Can Bull Med Hist ; 39(1): 1-36, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35506606

RESUMO

In 1979, the Canadian Society for the History of Medicine, founded in Quebec City, Canada, in 1950, inaugurated its first official organizational organ, Newsletter/Nouvelles, which ran for 10 issues in five annual volumes. In 1984, this modest means of institutional communication expanded to become the Canadian Bulletin of the History of Medicine / Bulletin canadien d'histoire de la médecine, a peer-reviewed journal that continues to the present. Central to the founding and operation of both publications was Kenneth B. Roberts of the Faculty of Medicine, Memorial University of Newfoundland. This discussion outlines the foundation, evolution, and activities of both these periodicals from 1979 to 1994. Their relationship to the growth of both the Canadian Society for the History of Medicine and the field of medical history in Canada are also delineated.


Assuntos
Medicina , Sociedades , Canadá , Quebeque
2.
Can Bull Med Hist ; : 1-25, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198641

RESUMO

This discussion considers recent historical works of eugenics and sterilization in Canada, but it is not an historiographic review essay or critique per se of this literature. Rather, by focussing on the topic of historic diagnostic categories such as "feeble-minded," "idiot," and "moron," methodological issues such as historical presentism and its possible interactions with the discourse of modern bioethics are examined. The conclusions derived are meant only to be cautionary, and are neither prescriptive nor proscriptive. Medical historians undertaking analyses of currently contentious topics that may directly involve or indirectly allude to "human subjects" or "vulnerable populations" perhaps ought to reflect on the degree, if any, they may be anachronistically writing contemporary bioethical categories into bygone eras.

3.
Can Bull Med Hist ; 34(2): 496-520, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28920726

RESUMO

This discussion considers recent historical works of eugenics and sterilization in Canada, but it is not an historiographic review essay or critique per se of this literature. Rather, by focussing on the topic of historic diagnostic categories such as "feeble-minded," "idiot," and "moron," methodological issues such as historical presentism and its possible interactions with the discourse of modern bioethics are examined. The conclusions derived are meant only to be cautionary, and are neither prescriptive nor proscriptive. Medical historians undertaking analyses of currently contentious topics that may directly involve or indirectly allude to "human subjects" or "vulnerable populations" perhaps ought to reflect on the degree, if any, they may be anachronistically writing contemporary bioethical categories into bygone eras.


Assuntos
Bioética , Eugenia (Ciência)/história , Sujeitos da Pesquisa , Populações Vulneráveis , Canadá , História do Século XX , Humanos
5.
J Hist Med Allied Sci ; 66(3): 380-94, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21724648

RESUMO

This essay review examines three books dealing with the founding and subsequent activities of Walter Reed Army Medical Center (WRAMC) and the evolution of military medicine from 1909 to 2009 recently published by the US Army's Borden Institute. Established by fellow army doctor William Borden to honor Walter Reed himself, WRAMC, located in Washington, DC, soon became the public and professional face of medical care for American soldiers. The discussion highlights the ongoing issue of the care and treatment of combat amputees; aspects of gender within military medicine; and WRAMC's function as an educational and research facility. Also discussed are the archival and documentary bases for these books and their utility for historians. Complimentary analysis of two of the books which are, in particular, explicitly about the history of WRAMC is contextualized within the celebration of the centennial of this army post contemporaneously with its closure, amalgamation, and relocation primarily to Maryland.


Assuntos
Livros/história , Pessoas com Deficiência/história , Hospitais Militares/história , Medicina Militar/história , Veteranos/história , Ferimentos e Lesões/história , Campanha Afegã de 2001- , Amputação Cirúrgica , História do Século XX , História do Século XXI , Humanos , Guerra do Iraque 2003-2011
7.
CMAJ ; 185(12): 1104, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23959283
8.
J Med Humanit ; 29(1): 45-54, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18058208

RESUMO

We provide the results of a systematic key-informant review of medical humanities curricula at fourteen of Canada's seventeen medical schools. This survey was the first of its kind. We found a wide diversity of views among medical educators as to what constitutes the medical humanities, and a lack of consensus on how best to train medical students in the field. In fact, it is not clear that consensus has been attempted - or is even desirable - given that Canadian medical humanities programs are largely shaped by individual educators' interests, experience and passions. This anarchic approach to teaching the medical humanities contrasts sharply with teaching in the clinical sciences where national accreditation processes attempt to ensure that doctors graduating from different schools have roughly the same knowledge (or at least have passed the same exams). We argue that medical humanities are marginalized in Canadian curricula because they are considered to be at odds philosophically with the current dominant culture of evidence-based medicine (EBM). In such a culture where adhering to a consensual standard is a measure of worth, the medical humanities - which defy easy metrical appraisal - are vulnerable. We close with a plea for medical education to become more comfortable in the borderlands between EBM and humanities approaches.


Assuntos
Ciências Humanas/educação , Faculdades de Medicina , Canadá , Currículo , Medicina Baseada em Evidências , Humanos , Entrevistas como Assunto
9.
J Clin Pathol ; 58(7): 687-94, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15976333

RESUMO

BACKGROUND: Upper gastrointestinal tract intestinal metaplasia (IM) is termed Barrett's oesophagus (BO) or gastric intestinal metaplasia (GIM), depending on its location. BO and GIM are associated with chemical exposure resulting from gastro-oesophageal reflux and chronic Helicobacter pylori infection, respectively. Paneth cells (PCs), characterised by cytoplasmic eosinophilic granules, are found in a subset of IM at these sites, but histology may not accurately detect them. AIM: To determine human defensin 5 (HD5; an antimicrobial peptide produced by PCs) expression in BO and GIM, and to investigate its association with H pylori infection. METHODS: Endoscopic biopsies from 33 patients with BO and 51 with GIM, and control tissues, were examined by routine histology and for H pylori infection and HD5 mRNA and protein expression. RESULTS: In normal tissues, HD5 expression was specific for PCs in the small intestine. Five patients with BE and 42 with GIM expressed HD5, but few HD5 expressing cells in IM had the characteristic histological features of PCs. Most HD5 positive specimens were H pylori infected and most HD5 negative specimens were not infected. CONCLUSIONS: HD5 immunohistochemistry was often positive in IM when PCs were absent by conventional histology. Thus, HD5 immunohistochemistry may be superior to histology for identifying metaplastic PCs and distinguishing GIM from BO. The higher frequency of HD5 expression in GIM than in BO is associated with a higher frequency of H pylori infection, suggesting that in IM PCs may form part of the mucosal antibacterial response.


Assuntos
Esôfago de Barrett/metabolismo , Defensinas/metabolismo , Mucosa Gástrica/metabolismo , Adulto , Idoso , Esôfago de Barrett/microbiologia , Western Blotting/métodos , Defensinas/genética , Defensinas/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Junção Esofagogástrica/metabolismo , Junção Esofagogástrica/patologia , Feminino , Mucosa Gástrica/patologia , Expressão Gênica , Infecções por Helicobacter/complicações , Infecções por Helicobacter/metabolismo , Helicobacter pylori , Humanos , Masculino , Metaplasia/metabolismo , Metaplasia/microbiologia , Pessoa de Meia-Idade , Celulas de Paneth/metabolismo , Celulas de Paneth/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
10.
Aliment Pharmacol Ther ; 18(10): 995-1002, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14616165

RESUMO

BACKGROUND: The 13C-galactose breath test has been reported to be an accurate, non-invasive method for the assessment of liver function. AIMS: To determine the optimal doses of labelled and unlabelled carrier galactose necessary to perform the 13C-galactose breath test, to assess the utility of the 13C-galactose breath test in distinguishing between normal subjects and those with liver cirrhosis and to determine whether the 13C-galactose breath test can stratify patients with cirrhosis based on their Child-Pugh score. METHODS: Twenty-three control subjects and 30 patients with liver cirrhosis received fixed doses of unlabelled carrier galactose and labelled 13C-galactose. Breath samples were collected just before and at 30-min intervals up to 4 h after the ingestion of unlabelled carrier galactose and labelled 13C-galactose. Each sample was analysed for its 13CO2 content. RESULTS: Doses of 25 g/m2 of unlabelled carrier galactose and 100 mg of 13C-galactose had the greatest sensitivity (93%; 95% confidence interval, 76-99%) and specificity (87%; 95% confidence interval, 65-97%) for distinguishing between normal subjects and cirrhotics when the test was performed 2 h after ingestion. The 13C-galactose breath test was also able to distinguish between class A and class B or C cirrhotics. CONCLUSION: The 13C-galactose breath test is a useful non-invasive tool for distinguishing between healthy subjects and patients with liver cirrhosis and between cirrhotics with well-compensated liver disease and those with decompensated liver disease.


Assuntos
Galactose , Hepatopatias/diagnóstico , Testes Respiratórios , Radioisótopos de Carbono , Feminino , Galactose/sangue , Humanos , Hepatopatias/fisiopatologia , Testes de Função Hepática/métodos , Testes de Função Hepática/normas , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade
11.
IEEE Trans Neural Netw ; 5(2): 240-54, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-18267794

RESUMO

We propose a robust learning algorithm and apply it to recurrent neural networks. This algorithm is based on filtering outliers from the data and then estimating parameters from the filtered data. The filtering removes outliers from both the target function and the inputs of the neural network. The filtering is soft in that some outliers are neither completely rejected nor accepted. To show the need for robust recurrent networks, we compare the predictive ability of least squares estimated recurrent networks on synthetic data and on the Puget Power Electric Demand time series. These investigations result in a class of recurrent neural networks, NARMA(p,q), which show advantages over feedforward neural networks for time series with a moving average component. Conventional least squares methods of fitting NARMA(p,q) neural network models are shown to suffer a lack of robustness towards outliers. This sensitivity to outliers is demonstrated on both the synthetic and real data sets. Filtering the Puget Power Electric Demand time series is shown to automatically remove the outliers due to holidays. Neural networks trained on filtered data are then shown to give better predictions than neural networks trained on unfiltered time series.

12.
J Am Dent Assoc ; 101(4): 655-60, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6934219

RESUMO

A simple and inexpensive dental office billing and accounting system has been presented which makes it possible for the average dentist to monitor the practice continuously in regard to fees, expenses, collection efficiency, and productivity without the expense and inconvenience of using a computer service. Computers should be reserved for more challenging tasks.


Assuntos
Administração Financeira/métodos , Administração da Prática Odontológica/economia , Contas a Pagar e a Receber , Computadores , Eficiência , Crédito e Cobrança de Pacientes , Registros
13.
Am J Vet Res ; 39(2): 249-53, 1978 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-629458

RESUMO

A biomechanical model of running has been presented. A basic premise has been that the swing time is nearly independent of speed. In fact, both the racehorse and the trotter have nearly equal swing times. Consequently, as speed increases and the stance phase becomes shorter, the horse must compensate by increasing his extension or the length of the airborne phase (or both). The safe speed which allows the horse adequate preparation time for contact of a leg with the ground is calculated, using a stride-by-stride analysis of the motion of the horse. This is seen to be a very sensitive function of the overlap time in the gait. The overlap between the legs appears to affect both the ultimate performance potential of the horse and also his prospects for soundness.


Assuntos
Marcha , Cavalos/fisiologia , Modelos Biológicos , Animais , Fenômenos Biomecânicos , Membro Anterior/fisiologia
14.
Am J Vet Res ; 37(11): 1251-5, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-984554

RESUMO

The force plate can measure a wide range of effects in the horse. The same instrument can record forces from more than a ton in the galloping animal to 25 g associated with the action of the heart. In all probability, the force plate will develop into a valuable clinical instrument.


Assuntos
Cavalos/fisiologia , Animais , Fenômenos Biomecânicos , Membro Anterior/fisiologia , Frequência Cardíaca , Membro Posterior/fisiologia , Locomoção
15.
Am J Vet Res ; 36(12): 1709-13, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-173210

RESUMO

The serum of lipoproteins of 10 Morgan and 8 Thoroughbred horses were examined by 2 methods of polyacrylamide gel electrophoresis. A significant breed difference in the beta-lipoprotein to alpha-lipoprotein ratio was seen in gradient slab electrophoresis. A breed difference in the number of peaks, but no difference in beta-lipoprotein to alpha-lipoprotein ratio, was found in disc gel electrophoresis. These results have been correlated to indicate differences in charge of alpha-lipoprotein components and in size of beta-lipoprotein components between these 2 breeds of horses.


Assuntos
Cavalos/sangue , Lipoproteínas/sangue , Animais , Cruzamento , Feminino , Doenças do Pé/sangue , Doenças do Pé/veterinária , Casco e Garras , Doenças dos Cavalos/sangue , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino
16.
Am J Vet Res ; 36(12): 1715-7, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-173211

RESUMO

The serum lipoprotein fractions from 5 Morgan and 5 Thoroughbred horses were isolated by preparative ultracentrifugation, chemically analyzed for lipid composition, and studied by 2 methods of polyacrylamide gel electrophoresis to determine electrophoretic mobility. Breed differences were not seen in the relative percentages of the lipid classes found in the various fractions. Normally, horses, like most animals, carry the majority of their lipid in high-density lipoproteins. Electrophoretically, the only difference seen between breeds occurred on disc electrophoresis where the extra band, which is characteristic of lipoprotein profiles of Morgans, was found in the high-density lipoprotein fraction.


Assuntos
Cavalos/sangue , Lipídeos/sangue , Lipoproteínas/sangue , Animais , Cruzamento , Colesterol/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Masculino , Triglicerídeos/sangue
17.
Am J Vet Res ; 36(12): 1705-8, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1200441

RESUMO

Concentrations of serum phospholipids, triglycerides, total cholesterol, nonesterified fatty acids, and glucose were determined for 9 months (September, 1972, to May, 1973) in 19 fasting horses and ponies (8 Morgan horses, 7 Thoroughbred horses, and 4 Shetland Ponies). Morgan horses had higher concentrations of total lipid than did Thoroughbreds, although the relative proportions of each type of lipid were similar in the 2 breeds. Shetland Ponies had higher nonesterified fatty acid and lower glucose concentrations than did either breed of horse. In both breeds of horses, concentrations of serum triglycerides in the cold months (December to March) were lower than those in the warm months. In the Shetland Pony, there was no seasonal variation in triglycerides, but a significant increase was seen in concentration of nonesterified fatty acids in the cold months. The significance of these findings is discussed.


Assuntos
Glicemia/análise , Cavalos/sangue , Lipídeos/sangue , Animais , Cruzamento , Colesterol/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Masculino , Fosfolipídeos/sangue , Gravidez , Estações do Ano , Triglicerídeos/sangue
18.
J Appl Behav Anal ; 33(1): 79-83, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10738954

RESUMO

An adolescent with severe mental retardation and cerebral palsy who displayed attention-maintained destructive behavior was exposed to noncontingent reinforcer delivery (NCR) with either a high-preference or a low-preference stimulus while reinforcement for destructive behavior with attention remained in effect (i.e., NCR without extinction). NCR without extinction was effective only when the high-preference stimulus was available, suggesting that systematic assessment of stimulus quality may enhance the effectiveness of NCR with alternative stimuli.


Assuntos
Agressão/psicologia , Terapia Comportamental/métodos , Paralisia Cerebral/reabilitação , Deficiência Intelectual/reabilitação , Esquema de Reforço , Comportamento Autodestrutivo/prevenção & controle , Adolescente , Atenção , Paralisia Cerebral/psicologia , Humanos , Deficiência Intelectual/psicologia , Masculino , Motivação , Comportamento Autodestrutivo/psicologia
19.
Int J Neural Syst ; 8(4): 399-415, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9730017

RESUMO

In this paper we present a neural network extended Kalman filter for modeling noisy financial time series. The neural network is employed to estimate the nonlinear dynamics of the extended Kalman filter. Conditions for the neural network weight matrix are provided to guarantee the stability of the filter. The extended Kalman filter presented is designed to filter three types of noise commonly observed in financial data: process noise, measurement noise, and arrival noise. The erratic arrival of data (arrival noise) results in the neural network predictions being iterated into the future. Constraining the neural network to have a fixed point at the origin produces better iterated predictions and more stable results. The performance of constrained and unconstrained neural networks within the extended Kalman filter is demonstrated on "Quote" tick data from the $/DM exchange rate (1993-1995).


Assuntos
Inteligência Artificial , Modelos Econômicos , Redes Neurais de Computação , Algoritmos
20.
Int J Neural Syst ; 8(4): 457-71, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9730021

RESUMO

A hybrid neural network is used to predict the difference between the conventional option-pricing model and observed intraday option prices for stock index option futures. Confidence intervals derived with bootstrap methods are used in a trading strategy that only allows trades outside the estimated range of spurious model fits to be executed. Whilst hybrid neural network option pricing models can improve predictions they have bias. The hybrid option-pricing bias can be reduced with bootstrap methods. A modified bootstrap predictor is indexed by a parameter that allows the predictor to range from a pure bootstrap predictor, to a hybrid predictor, and finally the bagging predictor. The modified bootstrap predictor outperforms the hybrid and bagging predictors. Greatly improved performance was observed on the boundary of the training set and where only sparse training data exists. Finally, bootstrap bias estimates were studied.


Assuntos
Inteligência Artificial , Modelos Econômicos , Redes Neurais de Computação , Algoritmos , Computadores Híbridos
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