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1.
Phys Rev Lett ; 120(3): 031101, 2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29400499

RESUMEN

We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

2.
Phys Rev Lett ; 111(1): 011101, 2013 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-24027782

RESUMEN

We report on a clear solar-cycle variation of the Sun's shadow in the 10 TeV cosmic-ray flux observed by the Tibet air shower array during a full solar cycle from 1996 to 2009. In order to clarify the physical implications of the observed solar cycle variation, we develop numerical simulations of the Sun's shadow, using the potential field source surface model and the current sheet source surface (CSSS) model for the coronal magnetic field. We find that the intensity deficit in the simulated Sun's shadow is very sensitive to the coronal magnetic field structure, and the observed variation of the Sun's shadow is better reproduced by the CSSS model. This is the first successful attempt to evaluate the coronal magnetic field models by using the Sun's shadow observed in the TeV cosmic-ray flux.

3.
Cancer Lett ; 162(1): 39-48, 2001 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-11121861

RESUMEN

Chemosensitivity to the drugs plays a crucial role in the treatment of ovarian cancer. In this study, we evaluate the cytotoxicity of chemotherapeutic agents in six ovarian cancer cell lines; four clear cell adenocarcinoma and two serous papillary adenocarcinoma, using seven single drugs and seven sets of drug combinations with tetrazolium-based semiautomated colorimetric (MTT) assay. The drug concentration which produced 50% growth inhibition (IC50) of cisplatin was within clinically achievable range in five cell lines. The area under the curve (AUC) at IC50 of cyclophosphamide was below the clinically achievable AUC in two serous papillary cell lines. Paclitaxel was more effective in clear cells than serous papillary cells. The intensification of cytotoxicity was observed in the combinations of paclitaxel and cisplatin, and cyclophosphamide and cisplatin or 5-fluorouracil irrespective of histopathological characteristics of the original tumor. Our results indicate that ovarian cancer cell lines respond to chemotherapeutic agents heterogeneously depending upon histopathological features, indicating individualized regimens may improve survival in ovarian cancer patients.


Asunto(s)
Adenocarcinoma de Células Claras/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclofosfamida/farmacología , Fluorouracilo/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Adenocarcinoma de Células Claras/patología , Supervivencia Celular/efectos de los fármacos , Cisplatino/farmacología , Ciclofosfamida/administración & dosificación , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Femenino , Fluorouracilo/administración & dosificación , Humanos , Neoplasias Ováricas/patología , Paclitaxel/farmacología , Células Tumorales Cultivadas
4.
APMIS ; 102(4): 295-307, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7516673

RESUMEN

The effects of treatment in a hydrated autoclave (121 degrees C, 2 atm for 20 min), microwave oven (in water), and simple heating (60 degrees C overnight in distilled water or 90 degrees C for 10 min in ZnSO4) on the stainability of 56 antigens by commercially available antibodies in formalin-fixed paraffin-embedded tissue sections were evaluated. The detectability of nuclear antigens, glycoprotein, lymphocytic surface markers, and chromogranin A was significantly and reproducibly improved by these treatments, whereas the detectability of viral antigens and peptide hormones was attenuated or unchanged. This enhancement includes not only the distinctiveness of the positive staining, but also the number of positive cells, as revealed by comparing serial sections. Among these four heating procedures, microwave heating and autoclaving were more effective than the others on p53, c-erbB-2, and CA125, whereas simple heating was best for smooth-muscle actin (HHF35 and CGA7). Generally the effects of the heating procedures for these antigens were consistent among the cases, but the effects on GFAP varied with the case. The alterations we observed could significantly influence the interpretation of immunohistochemical staining of currently popular tumor markers such as p53 in terms of their prevalence (28% vs 64% in gastric cancer; 36% vs 82% in metastatic liver cancer) and other diagnostically important markers.


Asunto(s)
Epítopos/química , Inmunohistoquímica/métodos , Reacciones Antígeno-Anticuerpo , Antígenos de Neoplasias/inmunología , Antígenos de Superficie/inmunología , Membrana Celular/inmunología , Citoesqueleto/inmunología , Fijadores , Calor , Humanos , Técnicas In Vitro , Microondas , Agua
5.
Arch Ophthalmol ; 116(4): 535-7, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9565058

RESUMEN

We have developed a technique of staining the anterior capsule with a solution of indocyanine green that facilitates performance of the circular continuous capsulorrhexis in eyes with a mature cataract. We compared the results of phacoemulsification and intraocular lens implantation in 10 eyes with the capsule stained with results of 10 eyes having the same procedure with standard circular continuous capsulorrhexis. The results of specular microscopy and laser flare-cell photometry showed no statistically significant differences between the 2 groups. Although the safety of intraocular indocyanine green dye has not yet been definitively established, the findings of this pilot study suggest that it is safe and useful in visualizing the anterior capsule of a mature cataract during cataract surgery.


Asunto(s)
Capsulorrexis , Catarata/complicaciones , Cápsula del Cristalino/anatomía & histología , Anciano , Capsulorrexis/métodos , Femenino , Colorantes Fluorescentes , Fluorofotometría , Humanos , Verde de Indocianina , Implantación de Lentes Intraoculares , Masculino , Persona de Mediana Edad , Facoemulsificación , Proyectos Piloto , Complicaciones Posoperatorias , Seguridad , Coloración y Etiquetado/métodos
6.
Arch Surg ; 131(2): 141-7, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8611069

RESUMEN

OBJECTIVE: To compare the results, limitations, and complications of the surgical treatment of bilateral hepatolithiasis and intrahepatic biliary strictures with left hepatectomy and without left hepatectomy. DESIGN: Case-controlled study. SETTING: Referral center. PATIENTS: During a 12-year period, 103 patients with bilateral hepatolithiasis and intrahepatic biliary strictures underwent surgical treatment. Group A (n = 73) received left hepatic resection (lateral segmentectomy or lobectomy) and postoperative biliary dilatation with residual stone extraction. Group B (n = 30) underwent the same procedures except for left hepatectomy. INTERVENTIONS: Left lateral segmentectomy or left lobectomy, choledocholithotomy, postoperative cholangioscopic treatments (electrohydraulic lithotripsy, other lithotripsy, lithotomy, balloon dilatation, etc. via T tube or precutaneous transhepatic route). MAIN OUTCOME MEASURES: Days of hospitalization, incidence of major and minor complications, mortality rates, and the rates of residual stones and stone recurrence were compared. RESULTS: Group A and B had similarly low postoperative 1-month mortality rates of 5.5% and 6.7%, respectively. The main cause of death in both groups was uncontrollable septicemia. The main major complications in group A were intra-abdominal abscess and upper gastrointestinal bleeding; the major complication in group B was massive hemobilia. Group B had a significantly higher overall rate of complications (53.3% vs 23.3%, P < .01) and a longer hospital stay than group A (median, 72 days vs 28 days, P < .03). When complications were classified as major or minor, only minor complications showed a significant difference (30% vs 13.7%, P = .05). After using biliary stricture dilatation and stone extraction, the rate of residual stones in the right lobe was similar in both groups, but patients in group B had a significantly higher rate of residual stones (12.5% vs 0%, P < .02) and stone recurrence in the left lobe (19% vs 0%, P < .003) than those in group A. CONCLUSIONS: Partial resection of the left lobe in cases of bilateral hepatolithiasis and biliary strictures can effectively simplify problems in the treatment of bilateral hepatolithiasis and intrahepatic biliary strictures. In addition, not only were surgical complications not increased, but a decrease in complications from postoperative manipulations for stone clearance was noted in our series.


Asunto(s)
Cálculos/cirugía , Cálculos/terapia , Colestasis Intrahepática/cirugía , Colestasis Intrahepática/terapia , Hepatectomía , Hepatopatías/cirugía , Hepatopatías/terapia , Absceso Abdominal/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Cateterismo , Colangiografía , Dilatación , Femenino , Cálculos Biliares/cirugía , Cálculos Biliares/terapia , Hemorragia Gastrointestinal/etiología , Hemobilia/etiología , Hepatectomía/efectos adversos , Hepatectomía/métodos , Hospitalización , Humanos , Tiempo de Internación , Litotricia , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Recurrencia , Sepsis/etiología , Tasa de Supervivencia
7.
Arch Surg ; 129(10): 1097-102, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7944942

RESUMEN

OBJECTIVE: To investigate the clinical characteristics of a coexisting sharp ductal angulation (< 90 degrees) with biliary stricture and to evaluate the difficulties it imposes in the management of retained or recurrent hepatolithiasis. DESIGN: Case-controlled study. SETTING: A referral center. PATIENTS: Eighteen consecutive patients having right-sided hepatolithiasis and a coexisting sharp ductal angulation associated with biliary stricture (group 1) were compared with 84 patients matched with sex, age, and conditions of hepatolithiasis and intrahepatic biliary stricture(s) but no sharp angulated duct (group 2). INTERVENTION: Postoperative cholangioscopic management (electrohydraulic lithotripsy or other lithotripsy, lithotomy, balloon dilation, biopsy, etc, via T-tube tract or percutaneous transhepatic route). MAIN OUTCOME MEASURES: Sessions of manipulations, incidence of complications associated with interventions or disease, and mortality were compared. RESULTS: Patients of group 1 needed more sessions of postoperative manipulation of stones and strictures (13.7 +/- 4.2 vs 8.0 +/- 2.3; P < .001). During management, there was a significantly increased vulnerability of severe and/or recurrent cholangitis (66.7% vs 9.5%; P < .001), septic shock (77.8% vs 11.9%; P < .001), liver abscess (55.6% vs 7.1%; P < .001), or massive hemobilia (33.3% vs 7.4%) in group 1 than in group 2. Their risks of coexisting secondary biliary cirrhosis (55.6% vs 9.5%; P < .001) and/or cholangiocarcinoma (16.6% vs 2.4%; P < .04) and mortality (27.8% vs 4.8%; P < .01) were also significantly higher in group 1. CONCLUSION: Our results suggest that the coexisting sharp ductal angulation with biliary strictures in right-sided hepatolithiasis is a distinct difficult clinical entity in the field of biliary tract calculi.


Asunto(s)
Conductos Biliares Intrahepáticos/patología , Cálculos/complicaciones , Hepatopatías/complicaciones , Adulto , Estudios de Casos y Controles , Constricción Patológica/complicaciones , Femenino , Humanos , Hepatopatías/patología , Masculino , Persona de Mediana Edad
8.
Eur J Radiol ; 18(1): 1-5, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8168572

RESUMEN

An intravascular foreign body is an iatrogenic complication that occurs during arterial or venous catheterization or interventional procedures. The foreign body could either be a catheter fragment, a dislodged coil, or a steel guide wire. From January 1987 to December 1992, 12 cases of intravascular foreign-body removals were performed by a percutaneous method at Mackay Memorial Hospital. Of the 12 cases, five were dislodged steel guide wires, four were broken CVP catheters, two were dislodged coils, and one was Port-A fragment. The techniques we used were the loop-snare technique (two cases) and stone basket retriever (10 cases). Eleven cases of intravascular foreign bodies were removed by non-surgical percutaneous retrieval but one case was a failure due to improper extraction of a dislodged steel guide wire. The patient received surgical extraction by regional venotomy finally. No major complications were noted during or after these procedures.


Asunto(s)
Vasos Sanguíneos , Cuerpos Extraños/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Angiografía , Cateterismo/efectos adversos , Niño , Preescolar , Embolización Terapéutica/efectos adversos , Falla de Equipo , Femenino , Cuerpos Extraños/diagnóstico por imagen , Cuerpos Extraños/etiología , Humanos , Masculino , Persona de Mediana Edad
9.
Intern Med ; 40(9): 936-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11579960

RESUMEN

A case of systemic rhabomyolysis after acetonitrile exposure is reported. A 35-year-old previously healthy man suffered from vomiting, convulsion and consciousness loss 15 hours after exposure to acetonitrile. Since acetonitrile is known to be metabolized into cyanide, antidote therapy against cyanide poisoning was given. On admission, pain and all-over muscle swelling were marked. Although the initial therapy was effective, rhabdomyolysis and then acute renal failure developed. Renal function improved very slowly after six weeks of hemodialysis, but atrophy of the muscles remained. The rhabdomyolysis may have been caused by toxicity of the cyanide itself in combination with hypoxia and convulsion.


Asunto(s)
Acetonitrilos/envenenamiento , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/diagnóstico , Exposición Profesional/efectos adversos , Rabdomiólisis/inducido químicamente , Rabdomiólisis/diagnóstico , Adulto , Humanos , Masculino , Intoxicación/diagnóstico , Intoxicación/terapia , Índice de Severidad de la Enfermedad
10.
Yakugaku Zasshi ; 114(1): 33-8, 1994 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-8133457

RESUMEN

A simple and precise method was established for the determination of synephrine in oriental pharmaceutical decoctions containing Evodiae Fructus using high-performance liquid chromatography with sodium dodecyl sulfate (SDS) as an ion-pair reagent. Synephrine was eluted within 25 min without interference from co-existing components using an ODS column and a mixture of water-acetonitrile-SDS-phosphoric acid (70:30:0.5:0.1, v/v/w/v) as a mobile phase.


Asunto(s)
Medicamentos Herbarios Chinos/química , Sinefrina/análisis , Cromatografía Líquida de Alta Presión
11.
Nippon Ganka Gakkai Zasshi ; 96(9): 1154-60, 1992 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-1414706

RESUMEN

The relationship between microalbuminuria indicated by the logarithm of the albumin index and the stage of diabetic retinopathy was investigated using 175 diabetic subjects. The relationship and its dependence on the duration and the age of onset of diabetes were analyzed statistically with logistic regression. In younger-onset subjects, microalbuminuria was strongly related to the stage of retinopathy, but in older-onset subjects, the relationship showed to lack. For each subject, the frequency of retinopathy was predicted by the estimated probability calculated with the regression model. When the critical probability was 50%, the sensitivity and specificity were 53.1% and 76.2%, respectively. These results indicated that the regression model using the albumin index might be a useful method to predict the frequency of diabetic retinopathy even without ophthalmoscopic examination.


Asunto(s)
Albuminuria/orina , Retinopatía Diabética/etiología , Adulto , Factores de Edad , Anciano , Retinopatía Diabética/diagnóstico , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Probabilidad , Sensibilidad y Especificidad
12.
Nippon Ganka Gakkai Zasshi ; 98(3): 264-9, 1994 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-8154384

RESUMEN

The vitreous in both normal eyes of 671 normal subjects was studied biomicroscopically. The results obtained were as follows: 1. In 618 cases of a refractive error less than -3D (group A) and 53 cases of refractive error over -3D (group B), the incidence of posterior vitreous detachment (PVD) in both eyes increased with age and the absence of PVD in both eyes decreased with age. The percentage of cases with PVD in one eye and no PVD in the other eye was less than 22% in all age groups. 2. There was no significant difference in the degree of vitreous liquefaction between the right and the left eyes. The degree of vitreous liquefaction was also age-related. 3. In the cases with PVD in one eye and no PVD in the other eye, a higher incidence of mild vitreous liquefaction was found in group A than in group B. 4. PVD without collapsed vitreous (simple PVD) in both eyes was observed only in group A. 5. Our results indicated that the vitreous findings in both eyes of an individual were almost identical, and PVD may occur with less vitreous liquefaction in group A than in group B.


Asunto(s)
Cuerpo Vítreo/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/patología , Niño , Oftalmopatías/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
13.
Gan To Kagaku Ryoho ; 25(13): 2069-74, 1998 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-9838909

RESUMEN

Photodynamic therapy (PDT) is a treatment modality that utilizes a photosensitizing drug activated by laser generated light. PDT is effective for oncologic applications. Many cancer patients have undergone a hematoporphyrin derivative (HpD)-mediated PDT. The HpD showed a side effect causing prolonged cutaneous photosensitivity. But ATX-S10, a new photosensitizer, provides rapid plasma and tissue clearance, comparable photoactivation efficiency, and superior light absorption of visible red. In this study, the tumor rejection mechanisms of PDT using ATX-S10 on HeLa tumors in nude mice were investigated with morphological and fluorometric methods. The mice were intracutaneously inoculated with HeLa cells, 5 x 10(5) or 1 x 10(7) cells. When tumors grew to about 10-12 mm in diameter, mice were intraperitoneally administered ATX-S10, 30 mg/kg, and 2 hours later the ATX-S10 in tumors was indirectly measured by a fluorometric machine, PMA-10 (Hamamatsu Photonics K. K.) and the tumors were irradiated by Optical Parametric Oscillator (Hamamatsu Photonics K. K.) tuned to a wave length at 670 nm, 5 mJ/pulse, 100 J/tumor. Before and after the irradiation, the effective mechanisms of PDT with ATX-S10 were studied by histological and ultrastructural approaches. The results showed occlusive thrombi in the microvasculature of the tumors and tumor cell death. These occlusive thrombi were observed within one hour after PDT at both light and electron microscopy levels, and were more remarkable as time passed after PDT. Therefore, the morphological studies of PDT with ATX-S10 suggested that the rejection mechanisms occurred mainly as a result of the destructive changes of the microvasculature in the tumors first, and secondly or simultaneously, tumor cells were destroyed through necrosis, and finally the tumors were rejected.


Asunto(s)
Colorantes Fluorescentes/farmacología , Fármacos Fotosensibilizantes/farmacología , Porfirinas/farmacología , Animales , Colorantes Fluorescentes/química , Células HeLa/efectos de los fármacos , Células HeLa/ultraestructura , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Fármacos Fotosensibilizantes/química , Porfirinas/química
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