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1.
Taehan Yongsang Uihakhoe Chi ; 82(1): 201-206, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36237468

RESUMO

The most common malignant tumors in the colon are adenocarcinomas, while leiomyosarcoma (LMS) are rare. Here, we report a case of LMS of the sigmoid colon in a 73-year-old man who presented with sigmoido-rectal intussusception, which was discovered by abdominal computed tomography. As LMS of the colon is uncommon and is rarely associated with intussusception, we have described the imaging features in this case report.

2.
Yonsei Med J ; 61(6): 547-552, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32469179

RESUMO

Fascicular involvement of the median nerve trunk in the upper arm is uncommon in cases of peripheral neuropathy, and its symptoms are consistent with those of anterior interosseous nerve (AIN) syndrome. We report three cases of focal anterior interosseous fascicular involvement in the median nerve trunk presenting as AIN palsy. Our report emphasizes the unique ultrasonographic and magnetic resonance imaging (MRI) features of swelling, hourglass-like constriction and torsion, and entwinement of the nerve fascicle of the dorsal region of the median nerve, which were confirmed surgically. On MRI, all patients showed denervation changes in the AIN territory, as well as in the median nerve territory, without compressing structures.


Assuntos
Fáscia/patologia , Imageamento por Ressonância Magnética , Nervo Mediano/diagnóstico por imagem , Nervo Mediano/patologia , Doenças do Sistema Nervoso Periférico/diagnóstico por imagem , Doenças do Sistema Nervoso Periférico/patologia , Ultrassonografia , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome , Adulto Jovem
3.
Korean J Radiol ; 17(3): 413-23, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27134529

RESUMO

With advances in implant technology, total ankle arthroplasty (TAA) has become an increasingly popular alternative to arthrodesis for the management of end-stage ankle arthritis. However, reports in the literature do not focus on the imaging features of TAA. Through a literature review, we demonstrate basic design features of the current ankle arthroplasty system, and the normal and abnormal postoperative imaging features associated with such devices. Pre- and postoperative evaluations of ankle arthroplasty mainly include radiography; in addition, computed tomography and magnetic resonance imaging provide further characterization of imaging abnormalities. Familiarization with multimodal imaging features of frequent procedural complications at various postoperative intervals is important in radiological practice.


Assuntos
Articulação do Tornozelo/diagnóstico por imagem , Artrite/terapia , Artroplastia de Substituição do Tornozelo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Tomografia Computadorizada por Raios X
4.
Korean J Radiol ; 17(2): 302-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26957918

RESUMO

We presented a rare case of a 64-year-old man with a combined anomaly of the bronchus and pulmonary artery that was detected incidentally. Computed tomography showed a hyperlucent, aerated sequestered segment of the right lower lung with an independent ectopic bronchus, which had no connection to the other airway. The affected segment was supplied by its own aberrant pulmonary artery branch from the right pulmonary trunk. This anomaly cannot be classified with any of the previously reported anomalies.


Assuntos
Sequestro Broncopulmonar/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Brônquios/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
5.
Intest Res ; 13(2): 122-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25931996

RESUMO

BACKGROUND/AIMS: The relationship between Crohn's disease and gallstones is established. However, the prevalence and risk factors for gallstones in patients with ulcerative colitis (UC) are not yet well understood. The aim of this study was to evaluate the prevalence and risk factors of gallstones in patients with UC. METHODS: This study was a retrospective single center study. A total of 87 patients with UC and 261 healthy controls were enrolled. Age, sex, and body mass index were matched. To investigate risk factors, the extent of UC, duration of disease, number of hospital admissions, and number of steroid treatments in patients with UC were evaluated. RESULTS: The prevalence of gallstones in patients with UC was 13.8%, whereas that in healthy controls was only 3.1% (P<0.001). For patients with UC, patients ≥50 years of age had a 3.6-times higher risk of gallstones compared to that in those <50 years of age, and the difference was statistically significant (odds ratio, 3.60; confidence interval, 1.03-12.61) in univariate analysis. There were no statistically significant disease-related risk factors for gallstones in UC patients. CONCLUSIONS: This is the first study of gallstone prevalence in Korean UC patients. In this study, patients with UC had a higher prevalence of gallstones compared to that in well-matched healthy controls. Age seemed to be a possible risk factor, and more studies are needed. Further prospective, large-scale studies will be required to confirm the risk factors for gallstones in UC patients.

6.
Korean J Gastroenterol ; 65(1): 57-61, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25603856

RESUMO

Osler-Weber-Rendu disease is a rare autosomal dominant disorder of fibrovascular tissues, characterized by a classic triad of mucocutaneous telangiectasias, recurrent hemorrhages, and a familial occurrence. Portosystemic encephalopathy in a patient with Osler-Weber-Rendu disease is rare, but we experienced a case presenting with recurrent portosystemic encephalopathy in Osler-Weber-Rendu disease. We report on a case of a 75-year-old female presenting with an altered mentality. Initial studies including brain imaging study did not reveal any specific cause for her mental status. She was diagnosed with the rare disease after a series of tests and received conservative treatment. Her neurological status recovered fully without complication after conservative treatment and she was discharged after 18 hospital days. This case demonstrated an extremely rare case of Osler-Weber-Rendu disease presenting as portosystemic encephalopathy treated successfully with conservative treatment. For patients who have shown hepatic encephalopathy without a definite cause, we recommend evaluation for the possibility of Osler-Weber-Rendu disease. Conservative treatment based on treatment of advanced liver cirrhosis could be an alternative solution.


Assuntos
Encefalopatia Hepática/diagnóstico , Telangiectasia Hemorrágica Hereditária/diagnóstico , Idoso , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Linhagem , Tomografia Computadorizada por Raios X , Malformações Vasculares/etiologia
7.
J Laparoendosc Adv Surg Tech A ; 24(11): 762-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25313667

RESUMO

BACKGROUND: Although laparoscopic appendectomy (LA) has been performed widely, the role of LA for complicated appendicitis remains controversial, and its role for periappendiceal abscess (PA) remains undefined. This study compared the clinical outcomes of LA and open appendectomy (OA) for PA diagnosed by radiologic investigation. PATIENTS AND METHODS: We conducted a retrospective review of 84 patients who underwent surgery for PA diagnosed by radiologic investigation between 2010 and 2013. Twenty-five patients underwent LA, and the remaining patients underwent OA. Patient characteristics, operative outcomes, and surgical complications were compared between the two groups. RESULTS: Three patients required conversion from LA to OA (12%). There were no significant differences in the overall complication (28% versus 25.4%; P=.8), wound infection (15.3% versus 4%; P=.27), stump leakage (4% versus 1.7%; P=.51), and postoperative ileus (4% versus 8.5%; P=.66) rates between the groups. The incidence of intraabdominal abscess (IAA) was significantly higher in the LA group (20% versus 3.4%; P=.02). In multivariate analysis, the risk factors for IAA were duration of drainage (P=.04) and type of operation (P=.006). The major complications rate was 2.4% in the total cohort, and the rate was significantly higher in the LA group (8% versus 0%; P=.02). CONCLUSIONS: For patients with PA, the rates of overall complications, wound infection, stump leakage, and postoperative ileus were similar for both procedures. However, LA resulted in a significantly higher incidence of IAA and major complications than OA.


Assuntos
Abscesso Abdominal/cirurgia , Apendicectomia/métodos , Apendicite/cirurgia , Laparoscopia/métodos , Abscesso Abdominal/diagnóstico por imagem , Adolescente , Adulto , Apendicectomia/efeitos adversos , Apendicite/diagnóstico por imagem , Feminino , Humanos , Incidência , Laparoscopia/efeitos adversos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Radiografia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
8.
Skeletal Radiol ; 43(5): 655-63, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24599341

RESUMO

OBJECTIVE: To identify the pattern of deltoid ligament injury after acute ankle injury and the relationship between ankle fracture and deltoid ligament tear by magnetic resonance imaging (MRI). MATERIALS AND METHODS: Thirty-six patients (32 male, and 4 female; mean age, 29.8 years) with acute deltoid ligament injury who had undergone MRI participated in this study. The deltoid ligament was classified as having 3 superficial and 2 deep components. An image analysis included the integrity and tear site of the deltoid ligament, and other associated injuries. Association between ankle fracture and deltoid ligament tear was assessed using Fisher's exact test (P < 0.05). RESULTS: Of the 36 patients, 21 (58.3 %) had tears in the superficial and deep deltoid ligaments, 6 (16.7 %) in the superficial ligaments only, and 4 (11.1 %) in the deep ligaments only. The most common tear site of the three components of the superficial deltoid and deep anterior tibiotalar ligaments was their proximal attachments (94 % and 91.7 % respectively), and that of the deep posterior tibiotalar ligament (pTTL) was its distal attachment (82.6 %). The common associated injuries were ankle fracture (63.9 %), syndesmosis tear (55.6 %), and lateral collateral ligament complex tear (44.4 %). All the components of the deltoid ligament were frequently torn in patients with ankle fractures (tibionavicular ligament, P = 0.009). CONCLUSION: The observed injury pattern of the deltoid ligament was complex and frequently associated with concomitant ankle pathology. The most common tear site of the superficial deltoid ligament was the medial malleolar attachment, whereas that of the deep pTTL was near its medial talar insertion.


Assuntos
Fraturas do Tornozelo , Traumatismos do Tornozelo/patologia , Articulação do Tornozelo/patologia , Ligamentos Articulares/lesões , Ligamentos Articulares/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Masculino
9.
Infect Chemother ; 45(3): 331-4, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24396635

RESUMO

Emphysematous pyelonephritis (EPN) is a rare, life-threatening complication of upper urinary tract infections that is characterized by the presence of gas in the renal parenchyma and perirenal space. It commonly occurs in diabetic patients. Escherichia coli are the most common causative organisms, with few reports implicating Citrobacter freundii as the etiologic agent in EPN. A 57-year-old woman with diabetes and neurogenic bladder visited at our department with confused mentality, myalgia, and general weakness. Further investigation revealed that the patient suffered from unilateral EPN with sepsis caused by C. freundii. The patient's condition was improved considerably with percutaneous drainage and use of intravenous antibiotics for several weeks. However, renal function eventually deteriorated to permanent renal failure, which required hemodialysis. In conclusion, C. freundii may be the causative pathogen of EPN in a patient with type 2 diabetes and neurogenic bladder.

10.
Yonsei Med J ; 52(5): 859-62, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21786454

RESUMO

Acutely aggravated dissecting flap and consequent occlusion of the superior mesenteric artery (SMA) by simple contrast passage during initial angiography for percutaneous stent placement is a uncommon event, which usually is not reported. After analysis of many factors that underlie development of such complications, we present herein one case of successful treatment of isolated SMA dissection and its complications with favorable outcomes during 25 months follow-up after percutaneous stent placement.


Assuntos
Dissecção Aórtica/cirurgia , Artéria Mesentérica Superior/cirurgia , Stents/efeitos adversos , Adulto , Angiografia/efeitos adversos , Meios de Contraste/efeitos adversos , Embolectomia , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Oclusão Vascular Mesentérica/etiologia , Tomografia Computadorizada por Raios X
11.
Korean J Gastroenterol ; 57(1): 14-8, 2011 Jan.
Artigo em Coreano | MEDLINE | ID: mdl-21258196

RESUMO

BACKGROUND/AIMS: Clinical manifestations of intestinal yersiniosis include enterocolitis, mesenteric adenitis, and terminal ileitis presenting with fever, right lower quadrant pain, and leukocytosis. According to a previous Korean study in 1997, Yersinia was revealed in two among 15 adult patients with mesenteric adenitis (13%). However, recent reports on the prevalence of Yersinia infection in adult patients are few. The aim of this study was to investigate the prevalence of Yersinia infection in adult patients with acute right lower quadrant pain. METHODS: Adult patients (>18 years) who visited Eulji medical center, due to acute right lower quadrant pain were enrolled prospectively from December 2007 to July 2009. Abdominal CT, stool culture, serologic test for Yersinia, and Widal test were performed. RESULTS: Among 115 patients, 5 patients were excluded due to positive Widal test or salmonella culture. In 110 patients, abdominal CT showed right colitis in 20 (18.2%), terminal ileitis in 16 (14.5%), mesenteric adenitis in 13 (11.8%), acute appendicitis in 10 (9.1%), acute diverticulitis in 7 (6.4%), non specific mucosal edema in 36 (32.7%) and no specific lesion in 8 (7.3%). Two (1.8%) of the 110 patients had antibodies to Yersinia. One patient showed acute enteritis and the other patient was diagnosed with acute appendicitis and underwent appendectomy. No Yersinia species were grown on stool or tissue culture. CONCLUSIONS: Nowadays, among adult Korean patients presenting with acute right lower quadrant pain, there have been few incidences of Yersinia infection.


Assuntos
Dor Abdominal/microbiologia , Yersiniose/diagnóstico , Yersiniose/epidemiologia , Yersinia/isolamento & purificação , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos/sangue , Anticorpos/imunologia , Apendicite/epidemiologia , Colite/epidemiologia , Diverticulite/epidemiologia , Edema/epidemiologia , Feminino , Humanos , Ileíte/epidemiologia , Linfadenite/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Tomografia Computadorizada por Raios X
12.
World J Gastroenterol ; 16(32): 4112-4, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-20731029

RESUMO

Prompt revascularization of the superior mesenteric artery (SMA) thrombotic occlusion can prevent intestinal infarction and decrease necrosis of the bowel segment. Herein, we describe two cases who underwent successful endovascular recanalization for acute SMA thrombosis using a primary aspiration thrombectomy because of possible consequent laparotomy for survey of bowel viability. The two patients had dramatic pain relief immediately after the procedure and remained symptom-free during the follow-up period.


Assuntos
Artéria Mesentérica Superior/cirurgia , Oclusão Vascular Mesentérica/cirurgia , Trombectomia/métodos , Idoso , Humanos , Masculino
13.
J Vasc Interv Radiol ; 21(8): 1287-91, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20656225

RESUMO

PURPOSE: To evaluate the feasibility of stent placement and the formation of tissue hyperplasia caused by stent placement in a rat esophageal model. MATERIALS AND METHODS: Twenty Sprague-Dawley rats were divided into four groups to assess differing stent diameters and design (group I, 4 mm diameter and a large mesh gap; group II, 5 mm diameter and a large mesh gap; group III, 5 mm diameter and a small mesh gap; and group IV, barbs added to the group III stents). Follow-up, 1-week, and 3-week esophagograms were obtained. Rats were euthanized 3 weeks after stent placement. Microscopic findings were evaluated in groups with an incidence of less than 50% stent migration. RESULTS: Stent placement was technically successful in all rats, and there were no procedure-related complications. No esophageal perforation occurred during follow-up. The incidence of stent migration was 100%, 60%, 40%, and 0% in groups I through IV, respectively. The esophagi with stent migration showed only a small amount of tissue hyperplasia; however, esophagi without stent migration showed gross tissue hyperplasia through the mesh. The microscopic findings were evaluated in groups III and IV. The degree of inflammatory cell infiltration, papillary projection thickness, granulation tissue area, and percentage of the granulation tissue area were higher in group IV than in group III; however, there was no statistical significance. CONCLUSIONS: Esophageal stent placement was feasible in a rat model, and formation of tissue hyperplasia was evident in rats without stent migration. With barbed stents, there was the least incidence of stent migration without esophageal perforation.


Assuntos
Proliferação de Células , Esôfago/lesões , Migração de Corpo Estranho/etiologia , Stents/efeitos adversos , Animais , Modelos Animais de Doenças , Perfuração Esofágica/etiologia , Perfuração Esofágica/patologia , Esôfago/diagnóstico por imagem , Esôfago/patologia , Estudos de Viabilidade , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/patologia , Migração de Corpo Estranho/prevenção & controle , Hiperplasia , Masculino , Desenho de Prótese , Radiografia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
14.
J Data Sci ; 8(1): 1-19, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21572901

RESUMO

High resolution of NMR spectroscopic data of biosamples are a rich source of information on the metabolic response to physiological variation or pathological events. There are many advantages of NMR techniques such as the sample preparation is fast, simple and non-invasive. Statistical analysis of NMR spectra usually focuses on differential expression of large resonance intensity corresponding to abundant metabolites and involves several data preprocessing steps. In this paper we estimate functional components of spectra and test their significance using multiscale techniques. We also explore scaling in NMR spectra and use the systematic variability of scaling descriptors to predict the level of cysteine, an important precursor of glutathione, a control antioxidant in human body. This is motivated by high cost (in time and resources) of traditional methods for assessing cysteine level by high performance liquid chromatograph (HPLC).

15.
World J Gastroenterol ; 15(44): 5620-3, 2009 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-19938204

RESUMO

Lymphangioma, a benign neoplasm of the lymphatic system, is common in children but rare in adults. Its clinical manifestations include abdominal pain, nausea, vomiting and a palpable mass. However, abdominal sonography or abdominal computed tomography (CT) scan can also incidentally reveal lymphangioma. A larger or symptomatic lymphangioma is treated with total resection to prevent recurrence, infection, torsion and enlargement. Although lymphangioma rarely becomes malignant, its prognosis is generally good. We report a cystic lymphangioma of the spleen and retroperitoneum, which was incidentally found in a 56-year-old man who was hospitalized due to a colon mass. Physical examination showed no specific findings. Abdominal CT revealed a 5.7 cm, non-enhanced multilobulated cystic mass with multiple septa in the spleen and a 10 cm lobulated cystic mass in the paraaortic area. Splenectomy and retroperitoneal resection of the cystic mass were conducted. The endothelium of splenic and retroperitoneal cyst was immunohistochemically stained with D2-40 antibody. The patient was finally diagnosed with splenic cystic and retroperitoneal cavernous lymphangioma.


Assuntos
Linfangioma/diagnóstico , Neoplasias Retroperitoneais/diagnóstico , Espaço Retroperitoneal/patologia , Baço/patologia , Humanos , Imuno-Histoquímica/métodos , Masculino , Pessoa de Meia-Idade , Prognóstico , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
16.
Korean J Gastroenterol ; 54(4): 248-51, 2009 Oct.
Artigo em Coreano | MEDLINE | ID: mdl-19844145

RESUMO

Venous thrombosis and thromboembolism appear to occur more often in patient with inflammatory bowel disease (IBD). The cause of thrombotic complications in IBD is generally considered to be associated with hypercoagulable conditions. Its prevalence rate ranges from 1% to 8% in clinical studies and rises to 39% in autopsy, but the renal vein thrombosis is very rare complication in ulcerative colitis patient. A 24-year-old man presented with intermittent abdominal pain and hematochezia for 6 months and recently developed pitting edema for few weeks. He was diagnosed as severe ulcerative colitis involving whole colon combined with thrombosis in both renal veins by colonoscopy and computed tomography scan of abdomen. We used steroid for the treatment of ulcerative colitis and both intravenous lower molecular weight heparin and warfarin for renal vein thrombosis. His symptoms were improved after treatment and maintained with mesalazine and warfarin. Follow-up abdominal CT scan showed complete resolution of both renal vein thrombosis. Currently he has been followed up for 2 years with oral mesalazine.


Assuntos
Colite Ulcerativa/diagnóstico , Veias Renais , Trombose Venosa/diagnóstico , Anticoagulantes/uso terapêutico , Colite Ulcerativa/complicações , Colite Ulcerativa/patologia , Colonoscopia , Heparina/uso terapêutico , Humanos , Masculino , Proteína S/metabolismo , Tomografia Computadorizada por Raios X , Trombose Venosa/complicações , Trombose Venosa/diagnóstico por imagem , Varfarina/uso terapêutico , Adulto Jovem
17.
AJR Am J Roentgenol ; 193(2): W106-11, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19620410

RESUMO

OBJECTIVE: The objective of our study was to evaluate the feasibility and usefulness of the Bayesian classifier for predicting malignant renal cysts on MDCT. MATERIALS AND METHODS: Ninety-three complicated cysts with pathologic confirmation were enrolled. Patient age and sex and seven morphologic features of the cysts including the maximum diameter, wall features, wall thickness, septa features, measurable enhancement of the wall and septa, presence of calcification, and presence of an enhancing soft-tissue component were used to train the Bayesian classifier. Four radiologists independently reviewed the MDCT images, and the probability of malignancy in each cyst was rated by the radiologists and the Bayesian classifier. The diagnostic performances of the radiologists' visual decisions and the Bayesian classifier were then compared using receiver operating characteristic (ROC) curve analysis. The sensitivity and specificity were also compared between the visual decisions and the Bayesian classifier. RESULTS: The area under the ROC curve for predicting malignant renal cysts by the Bayesian classifier was greater than the visual decisions of three readers (reader 1, p = 0.02; reader 2, p < 0.01; reader 4, p = 0.02) and was similar to the visual decision of one reader (reader 3, p = 0.51). The specificity for predicting malignant renal cysts was greater by the Bayesian classifier than by the visual decisions in readers 2 (p = 0.04) and 4 (p = 0.02) and was similar in readers 1 (p = 0.68) and 3 (p = 1.00). In terms of sensitivity, there was no significant difference between the Bayesian classifier and the visual decisions in all four readers (p > 0.05). CONCLUSION: For predicting malignant renal cysts on MDCT, the Bayesian classifier is feasible and may improve diagnostic performance.


Assuntos
Teorema de Bayes , Interpretação de Imagem Assistida por Computador , Doenças Renais Císticas/diagnóstico por imagem , Doenças Renais Císticas/patologia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Modelos Estatísticos , Área Sob a Curva , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
18.
Biom J ; 48(3): 435-50, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16845907

RESUMO

A Bayesian model-based clustering approach is proposed for identifying differentially expressed genes in meta-analysis. A Bayesian hierarchical model is used as a scientific tool for combining information from different studies, and a mixture prior is used to separate differentially expressed genes from non-differentially expressed genes. Posterior estimation of the parameters and missing observations are done by using a simple Markov chain Monte Carlo method. From the estimated mixture model, useful measure of significance of a test such as the Bayesian false discovery rate (FDR), the local FDR (Efron et al., 2001), and the integration-driven discovery rate (IDR; Choi et al., 2003) can be easily computed. The model-based approach is also compared with commonly used permutation methods, and it is shown that the model-based approach is superior to the permutation methods when there are excessive under-expressed genes compared to over-expressed genes or vice versa. The proposed method is applied to four publicly available prostate cancer gene expression data sets and simulated data sets.


Assuntos
Análise por Conglomerados , Interpretação Estatística de Dados , Perfilação da Expressão Gênica/métodos , Modelos Genéticos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , Teorema de Bayes , Simulação por Computador , Metanálise como Assunto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
J Am Chem Soc ; 124(4): 615-9, 2002 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-11804492

RESUMO

Shape- and dopant-controlled magnetic semiconductor nanocrystals have been achieved by the thermolysis of nonpyrophoric and less reactive single molecular precursors under a monosurfactant system. Reaction parameters governing both the intrinsic crystalline phase and the growth regime (kinetic vs thermodynamic) are found to be important for the synthesis of various shapes of MnS nanocrystals that include cubes, spheres, 1-dimensional (1-D) monowires, and branched wires (bipods, tripods, and tetrapods). Obtained nanowires exhibit enhanced optical and magnetic properties compared to those of 0-D nanospheres. Proper choice of molecular precursors and kinetically driven low-temperature growth afford dopant controlled 1-D Cd1-xMn(x)S nanorods at high levels (up to approximately 12%) of Mn, which is supported by repeated surface exchange experiments and X-ray diffraction (XRD) and electron paramagnetic resonance (EPR) analyses.

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