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1.
World J Surg ; 38(4): 936-46, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24166026

RESUMO

BACKGROUND: The clinical benefits of conversion chemotherapy followed by liver resection for initially unresectable colorectal liver metastases are still controversial. The criteria for unresectability vary from one team to another. To clarify this issue, we retrospectively assessed the survival and characteristics of metastatic colorectal cancer (mCRC) patients with liver-limited disease (LLD) who underwent conversion therapy. METHOD: Our criteria for resectability depended on the size of the remnant liver volume (>30 %) and expected function after removal of all metastases. Between December 2007 and September 2011, a total of 115 patients were diagnosed as having mCRC with LLD and received chemotherapy. Among them, 47 had tumors that were initially diagnosed as resectable. They underwent hepatic resection after chemotherapy (resected group). Of the 67 tumors were initially diagnosed as unresectable, 12 became resectable after chemotherapy (conversion group), leaving 55 tumors that remained unresectable after chemotherapy (unresected group). RESULTS: The median follow-up was 25.2 months. Hepatic resection was more invasive in the conversion group than in the resected group. Median disease-free survival was significantly higher in the resected group than in the conversion group (p = 0.013). Overall survival (OS) was also higher in the resected group, but the difference was not significant (p = 0.36). However, OS was significantly higher in the conversion group than in the unresected group (p = 0.034). Multivariate analysis of the resected and conversion groups showed that OS was significantly negatively influenced by abnormal carcinoembryonic antigen levels at surgery (p = 0.037) and a hospital stay >30 days (p = 0.009). CONCLUSIONS: Our results showed that conversion chemotherapy could contribute to longer OS in mCRC patients with LLD.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/patologia , Hepatectomia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Terapia Neoadjuvante , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Capecitabina , Quimioterapia Adjuvante , Neoplasias Colorretais/mortalidade , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Feminino , Fluoruracila/análogos & derivados , Fluoruracila/uso terapêutico , Seguimentos , Humanos , Leucovorina/uso terapêutico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/uso terapêutico , Oxaloacetatos , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
2.
BJS Open ; 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894010

RESUMO

BACKGROUND: Severe inflammation with necrosis and fibrosis of the gallbladder in acute cholecystitis increases operative difficulty during laparoscopic cholecystectomy. This study aimed to assess the use of preoperative MRI in predicting pathological changes of the gallbladder associated with surgical difficulty. METHODS: Patients who underwent both preoperative MRI and early cholecystectomy for acute cholecystitis between 2012 and 2018 were identified retrospectively. On the basis of the layered pattern of the gallbladder wall on MRI, patients were classified into three groups: high signal intensity (HSI), intermediate signal intensity (ISI), and low signal intensity (LSI). The endpoint was the presence of pathological changes of the gallbladder associated with surgical difficulty, such as necrosis, abscess formation and fibrosis. RESULTS: Of 229 eligible patients, pathological changes associated with surgical difficulty were found in 17 (27 per cent) of 62 patients in the HSI group, 84 (85 per cent) of 99 patients in the ISI group, and 66 (97 per cent) of 68 patients in the LSI group (P < 0·001). For detecting these changes, intermediate to low signal intensity of the gallbladder wall had a sensitivity of 90 (95 per cent c.i. 84 to 94) per cent, specificity of 73 (60 to 83) per cent and accuracy of 85 (80 to 90) per cent. CONCLUSION: Preoperative MRI predicted pathological changes associated with surgical difficulty during laparoscopic cholecystectomy for acute cholecystitis.


ANTECEDENTES: La inflamación grave con necrosis y fibrosis de la vesícula biliar en la colecistitis aguda aumenta la dificultad quirúrgica durante la colecistectomía laparoscópica. Este estudio tuvo como objetivo evaluar el uso de la resonancia magnética preoperatoria (magnetic resonance imaging, MRI) para predecir los cambios patológicos de la vesícula biliar asociados con la dificultad quirúrgica. MÉTODOS: Los pacientes que se sometieron tanto a MRI preoperatoria como a colecistectomía precoz por colecistitis aguda entre 2012 y 2018 fueron identificados retrospectivamente. En base a la distribución en capas de la pared de la vesícula biliar en la MRI, los pacientes se clasificaron en tres grupos: (1) intensidad de señal alta (high signal intensity, HSI), (2) intensidad de señal intermedia (intermediate signal intensity, ISI) y (3) intensidad de señal baja (low signal intensity, LSI). El objetivo final fue la presencia de cambios patológicos en la vesícula biliar asociados con la dificultad quirúrgica, tales como necrosis, formación de abscesos y fibrosis. RESULTADOS: De los 229 pacientes elegibles, se documentaron cambios patológicos asociados con dificultad quirúrgica en 17 (27,4%) de 62 pacientes en el grupo HSI, 84 (84,8%) de 99 pacientes en el grupo ISI y 66 (97,1%) de 68 pacientes en el grupo LSI (P < 0,001). Para detectar estos cambios, la intensidad de señal de intermedia a baja de la pared de la vesícula biliar tuvo una sensibilidad del 89,8% (i.c. del 95% 84,2%-94,0%), una especificidad del 72.6% (i.c. del 95% 59,8%-83,1%) y una precisión del 85,2% (i.c. del 95% 79,9%-89,5%). CONCLUSIÓN: La MRI preoperatoria predijo los cambios patológicos asociados con la dificultad quirúrgica durante la colecistectomía laparoscópica por colecistitis aguda.

3.
Cancer Res ; 60(1): 64-9, 2000 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10646854

RESUMO

Insulin-like growth factor I (IGF-I) stimulates proliferation, survival, and differentiation in many cell types, including pediatric neuroblastomas. The effect is mediated via the type I IGF-I receptor (IGF-IR), which is essential for growth in these cells. Several lines of evidence indicate that IGF-IR function may be particularly important in the pathogenesis of neuroblastoma. Amplification of the N-myc oncogene or overexpression of N-Myc oncoprotein has been reported to be associated with resistance to therapy and poor prognosis of neuroblastomas. It was therefore of interest to analyze whether IGF-I signaling regulated expression of N-myc in KP-N-RT human neuroblastoma cells as an experimental model that has amplified N-myc. We found that IGF-I induces N-myc mRNA and protein in the KP-N-RT with maximums of four and six times more than the basal level at 2 and 3 h after stimulation, respectively. These effects of IGF-I were blocked by a neutralizing antibody against IGF-IR (alpha-IR3). Exogenous IGF-I induced phosphorylation and activation of extracellular signal-regulated kinases p44/42 (ERK1 and ERK2), with a maximal level 30 min after the stimulation. The MEK1 inhibitor PD98059 reduced IGF-I-mediated p44/42 MAPKs phosphorylation and produced a parallel reduction of IGF-I-stimulated N-Myc induction. Furthermore, both alpha-IR3 and PD98059 inhibited G1-S cell cycle progression stimulated by IGF-I. Our results demonstrate that IGF-I induces N-Myc in the KP-N-RT neuroblastoma cell line at the RNA level and establishes a clear correlation between N-Myc induction and activation of p44/42 MAPK signaling.


Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Proteínas de Neoplasias/fisiologia , Neuroblastoma/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Fase G1/efeitos dos fármacos , Humanos , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , RNA Mensageiro/metabolismo , Fase S/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
4.
Eur J Surg Oncol ; 41(3): 413-20, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25477268

RESUMO

BACKGROUND: In the current era of total mesorectal excision, local relapse remains a main cause of recurrence. Although standard treatment for locally recurrent rectal cancer (LRRC) has not been established, R0 resection represents the only potentially curative treatment. However, extended surgery accompanying bony pelvic resection is technically demanding and is still challenging. METHODS: Studied were 35 patients with LRRC who underwent combined resection of bony pelvis between August 2006 and October 2013. Safety and prognostic factors for survival were analyzed. Median follow-up was 33 months. RESULTS: Sacrectomy was performed in 32 patients and 3 patients underwent combined resection of the pubis and ischium. The dominant operative procedure was total pelvic exenteration in 30 (86%) patients. R0 resection was achieved in 27 (77%) patients. No patients died. Pelvic sepsis was the most frequent complication (40%). Recurrence developed in 20 (57%), with the lung the most frequent site (10 patients). Three-year local relapse-free survival (LRFS) and disease-free survival (DFS) were 72.1% and 32.7%, respectively. On multivariate analysis, R1 resection was the only independent risk factor for local recurrence (p = 0.010), and concomitant liver metastasis and initial non sphincter-preserving surgery were independent predictors of worse DFS (p = 0.008 and p = 0.042, respectively). CONCLUSIONS: Aggressive surgical treatment combined with bony resection for carefully selected patients with LRRC was safe with a high rate of R0 resection and favorable LRFS. However, DFS was not satisfactory even after R0 resection and the main cause was lung metastasis. Preventing distant recurrence might be a key to improve survival.


Assuntos
Carcinoma/cirurgia , Ísquio/cirurgia , Recidiva Local de Neoplasia/cirurgia , Exenteração Pélvica/métodos , Osso Púbico/cirurgia , Neoplasias Retais/cirurgia , Adulto , Idoso , Carcinoma/patologia , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Prognóstico , Neoplasias Retais/patologia
5.
Eur J Surg Oncol ; 41(11): 1464-70, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26329783

RESUMO

BACKGROUND: The purpose of this study was to evaluate the diagnostic value of dual-energy computed tomography (DECT) in detecting lymph node (LN) metastasis in patients with colorectal cancer. METHODS: Data from 81 LNs from 28 patients with colorectal adenocarcinoma were retrospectively analyzed. All patients received DECT before surgery without any neoadjuvant therapy. The diagnostic value was assessed using the iodine concentration (IC). RESULTS: In the pathological findings, 35 (43.2%) LNs from 13 patients were metastatic and 46 (56.8%) LNs from 17 patients were non-metastatic. The mean IC of metastatic LNs in the portal venous phase (PP) was 1.60 mg/ml, which was significantly lower compared with non-metastatic LNs (3.25 mg/ml, p < 0.001). Receiver operating characteristic (ROC) analysis revealed that the IC in PP had the highest ability to discriminate LN metastasis (area under the ROC curve [AUC] 0.932). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of IC in PP (cutoff 2.1 mg/ml) were 87.0%, 88.6%, 85.3%, 90.0%, and 87.9%, respectively. When clinically obvious metastatic LNs in conventional CT findings were excluded, 50 LNs remained (5 metastatic and 45 non-metastatic LNs). In this subgroup analysis, the IC in PP remained the most powerful predictor of metastatic LNs (cutoff: 2.1 mg/ml, AUC 0.933). CONCLUSIONS: The evaluation of IC in DECT may improve the diagnostic capabilities of discriminating metastatic LNs. This method may be particularly useful when conventional CT findings lead to equivocal results.


Assuntos
Adenocarcinoma/secundário , Neoplasias Colorretais/patologia , Iodo/metabolismo , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Adenocarcinoma/diagnóstico , Adulto , Idoso , Neoplasias Colorretais/diagnóstico por imagem , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Cintilografia , Reprodutibilidade dos Testes , Estudos Retrospectivos
6.
Bone Marrow Transplant ; 23(9): 971-4, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10338057

RESUMO

A useful marker for detecting minimal residual disease (MRD) has not been established yet in retinoblastoma. We assessed neuroendocrine protein gene product 9.5 (PGP9.5) expression, one of the markers for detecting MRD in neuroblastoma, in a patient with disseminated retinoblastoma. A 3-year-old boy with disseminated retinoblastoma in multiple bones and marrow was referred to our hospital. He received intensive treatment and has maintained CR for 48 months following myeloablative chemotherapy with hematopoietic stem cell transplantation (SCT). PGP9.5 expression was serially assessed by RT-PCR in peripheral blood mononuclear cells (PBMC), bone marrow cells (BMC) and mobilized peripheral blood stem cells (PBSC). Initially, his BMC consisted of 96% tumor cells which were proved to express PGP9.5 by RT-PCR. Moreover, PBMC were found to be positive for PGP9.5 indicating the presence of tumor cells in the peripheral blood. After intensive chemotherapy, PGP9.5 expression became negative in both PBMC and BMC. Prior to SCT, PBSC and BMC transplants were confirmed negative for PGP9.5 expression. It is suggested that PGP9.5 expression is a useful marker for evaluating therapeutic effects as well as detecting MRD in retinoblastoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Neoplasia Residual/diagnóstico , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Tioléster Hidrolases/genética , Criança , Terapia Combinada , Humanos , Masculino , Neoplasia Residual/genética , Reação em Cadeia da Polimerase , Neoplasias da Retina/tratamento farmacológico , Neoplasias da Retina/genética , Retinoblastoma/genética , Retinoblastoma/terapia , Tioléster Hidrolases/análise , Transplante Autólogo , Ubiquitina Tiolesterase
7.
Breast Cancer ; 4(3): 183-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-18843557

RESUMO

We report a case of a giant malignant phyllodes tumor examined by(99m)Tc-ses-tamibi (MIBI) mammoscintigraphy. The patient was a 51 year-old woman who complained of bleeding from a large mass in her right breast. The tumor was well circumscribed, with an ulcerized surface. The accumulation of(99m)Tc-MIBI in the tumor was recognized on(99m)Tc-MIBI scintigraphy. A standard radical mastectomy was performed with a wide margin of skin. The resected specimen measured 20 X 17 X 13 cm, weighed 2100 g and was histologically diagnosed as a malignant phyllodes tumor. The skin defect was reconstructed by a rectus abdominis musculocutaneous flap, with good cosmetic results.(99m)Tc-MIBI scintigraphy may have the potential to distinguish a malignant from benign phyllodes tumors.

8.
Nippon Ganka Gakkai Zasshi ; 105(11): 771-5, 2001 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-11758346

RESUMO

PURPOSE: We reviewed 115 eyes of 65 patients regarding the intraocular pressure(IOP) following laser in situ keratomileusis(LASIK). PATIENTS AND METHODS: The ages averaged 31.2 +/- 10.5(mean +/- standard deviation) years. The preoperative spherical equivalent averaged -6.85 +/- 2.54 (mean +/- standard deviation) D. A noncontact pneumatic tonometer and Goldmann applanation tonometer were used in measuring the IOP. RESULTS: The IOP difference before and after surgery was statistically significant(Mann-Whitney U test). The IOP was significantly corrected with the corrected diopter value, corneal thickness, and corneal curvature(Spearman coefficient by rank). CONCLUSION: The findings show that postoperative IOP may be underestimated due to decreased corneal thickness and curvature. Due attention has to be paid to this feature in evaluating IOP after LASIK.


Assuntos
Pressão Intraocular/fisiologia , Ceratomileuse Assistida por Excimer Laser In Situ , Adulto , Feminino , Humanos , Masculino , Período Pós-Operatório , Fatores de Risco , Tonometria Ocular
9.
Nihon Geka Gakkai Zasshi ; 85(9): 1143-6, 1984 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-6438481

RESUMO

Anti-cancer drugs in the forms of an emulsion, a microsphere, and of conjugates with high molecular dextran have been developed in our laboratories, namely a fat emulsion of anticancer drug, MMC-microsphere, or MMC-dextran conjugates. The main advantages of these forms of pharmaceutical preparation are that they give prolongation of pharmacological actions by slow release and that they are applicable for topical use because of their reduced toxicities to local tissue yet maintaining local therapeutic potency. In this study we found that the rate of sustained release of drugs and antitumor effects were enhanced when used in such modified forms of drugs for topical injections. Results of clinical trials of those drugs have been promising. However, the number of trials has been limited so far. Further studies would be required for evaluating on of their clinical utilities.


Assuntos
Antineoplásicos/administração & dosagem , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Emulsões , Feminino , Humanos , Infusões Intra-Arteriais , Masculino , Microesferas , Pessoa de Meia-Idade , Mitomicina , Mitomicinas/administração & dosagem
13.
Eye (Lond) ; 23(1): 63-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17932504

RESUMO

PURPOSE: External allergens are the main causative factor in the pathogenesis of allergic diseases; however, little is known about internal factors such as the biometrical structure of the eye. We investigated the relationship between refractive error and allergic conjunctivitis in order to reveal possible insights into the pathogenesis in 1015 subjects. METHODS: The patients were divided into four groups: contact lens wearers with allergic conjunctivitis (n=73), contact lens wearers without allergic conjunctivitis (n=59), non-contact lens wearers with allergic conjunctivitis (n=224), and non-contact lens wearers without allergic conjunctivitis (n=659). The spherical power, cylindrical power, corneal radius, and minimum and maximum corneal refractive powers were measured in all subjects. RESULTS: In the non-contact lens wearers, the spherical equivalent and spherical power were significantly lower in patients with allergic conjunctivitis than in patients without allergic conjunctivitis (-3.01+/-3.83 D vs-1.36+/-3.08 D, P<0.0001, and -2.64+/-3.63 D vs-1.05+/-2.88 D, P<0.0001, respectively), while there was no significant difference in any of the parameters between the contact lens wearers with and without allergic conjunctivitis. CONCLUSION: Refractive error may be a risk factor for allergic conjunctivitis.


Assuntos
Conjuntivite Alérgica/etiologia , Lentes de Contato , Erros de Refração/complicações , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
14.
Eye (Lond) ; 19(9): 995-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15389269

RESUMO

PURPOSE: The purpose of the current study is to evaluate the relation between various specific class E immunoglobulins (IgE) in the serum and allergic conjunctivitis in autumn. METHODS: Total IgE and specific IgE to 12 inhalant allergens were measured using the CAP system in 32 patients with allergic conjunctivitis in spring (spring group), 27 patients with allergic conjunctivitis in autumn (autumn group), and 40 healthy volunteers (control group). RESULTS: Specific IgE levels caused by house dust, Dermatophagoides pteronyssinus, and orchard grass were higher in the autumn group than in the spring group. The highest positivity rate for a specific allergen was 51.9% for house dust, followed by D. pteronyssinus(48.1%) in the autumn group, while the highest rate was 68.8 % for cedar pollen, followed by cypress pollen (59.4%) in the spring group. Correlation analysis showed that house dust was significantly correlated with animal epithelia, D. pteronyssinus, acarus, and Alternaria tenuis in the autumn group (P<0.001). CONCLUSIONS: These results suggest that house dust is the main cause of allergic conjunctivitis during autumn. In spring, cypress pollen is the largest cause of allergic conjunctivitis, while indoor allergens such as house dust, animal epithelia, D. pteronyssinus, and acarus are not causative allergens in Japan.


Assuntos
Alérgenos/imunologia , Conjuntivite Alérgica/imunologia , Imunoglobulina E/sangue , Estações do Ano , Adolescente , Adulto , Idoso , Especificidade de Anticorpos , Antígenos de Dermatophagoides/imunologia , Dermatophagoides pteronyssinus/imunologia , Poeira/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pólen/imunologia , Teste de Radioalergoadsorção
15.
Appl Opt ; 20(20): 3520-5, 1981 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20372211

RESUMO

The wave fronts of several types of diode laser are investigated by means of Mach-Zehnder and phase difference amplification interferometers. The astigmatic aberration tolerance of each diode laser is estimated using aberration theory to determine if the lasers are suitable as light sources for precise optical systems, such as laser beam printers and optical disks.

16.
Appl Opt ; 29(34): 5060-3, 1990 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20577510

RESUMO

A new method of designing geodesic lenses is described. The lens shape is expressed with a uniform function. The curvature of the lens shape is restricted within an upper limit to prevent the light leaking from the waveguide. The value of the curvature limit can be specified at the start of design calculation. A comparison with a former design method is also given. The numerical aperture of the lens is found to be improved up to 24%.

17.
Appl Opt ; 31(25): 5269-75, 1992 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20733705

RESUMO

To improve the access time of the optical disk, we have developed an integrated surface acoustic wave deflector. An end-coupled laser diode with a gradient-index lens, a half-wave plate, and a geodesic waveguide lens are integrated together with surface acoustic wave deflector on a Ti:LiNbO(3) waveguide. Consequently optical disk tracking on a read-only disk is achieved experimentally with this newly developed deflector. Fabrication techniques for geodesic lenses are also described particularly with respect to polishing and waveguide fabrication.

18.
Appl Opt ; 36(28): 7234-8, 1997 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18264232

RESUMO

In the novel optical system described here, four-color toners can be developed in one rotation of the photoconductor, and the color control information is given when the intensities of the laser power levels are changed and the two polarization directions are switched. A polarizing beam splitter between the common scanning optics and the photoconductor enables the laser beam to pass through a common scanning system and to illuminate two positions on the photoconductive material. The laser beam polarization direction is controlled by an electro-optical device immediately behind the laser. In each illuminated position, two-color toners are developed by a three-level (trilevel) photographic process. This simplified optical system eliminates the registration errors that occur with four-color information items and can be useful in high-speed printing systems.

19.
Appl Opt ; 31(22): 4559-62, 1992 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20725459

RESUMO

A method is presented for estimating the thermal conductivity of magneto-optical recording media by using the temperature dependence of their Kerr effect. The temperature distribution of a recording layer observed as the distribution of polarized light intensity is used to estimate the thermal conductivity of the recording media. The thermal conductivity of a TbFeCo film is between 0.08 and 0.18 W/cm degrees C, and the conductivity of an SiN film is <0.04 W/cm degrees C. Although these values are lower than the previously reported values, the performance parameters that we estimated by using them agree closely with the experimentally measured parameters. The proposed method thus seems valuable for quantitatively analyzing the thermal properties of magneto-optical recording media.

20.
Appl Opt ; 36(24): 5876-80, 1997 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-18259421

RESUMO

We demonstrate enhanced resolution printing using a variable spot-size laser diode. The near-field spot size of the laser diode can be changed by controlling the refractive-index distribution in the laser stripe through the injected current. The ratio of the minimum-to-maximum spot size is 2.1:1. This technology provides high-resolution printing without increasing the scanning frequency. Smoother character outlines that consist of finer steps are produced with this laser diode. An effective resolution of 1200 dots /in. (dpi) can be obtained by a printer system with 600-dpi resolution.

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