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1.
Dis Esophagus ; 30(4): 1-8, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28375483

RESUMEN

Bibliometric analysis highlights key topics and publications that have shaped the understanding and management of esophageal cancer (EC). Here, the 100 most cited manuscripts in the field of EC are analyzed. The Thomson Reuters Web of Science database with the search terms 'esophageal cancer' or 'esophageal carcinoma' or 'oesophageal cancer' or 'oesophageal carcinoma' or 'gastroscopy' was used to identify all English language full manuscripts for the study. The 100 most cited papers were further analyzed by topic, journal, author, year, and institution. A total of 121,556 eligible papers were returned and the median (range) citation number was 406.5 (1833 to 293). The most cited paper focused on the role of perioperative chemotherpy in EC (1833 citations). Gastroenterology published the highest number of papers (n = 15, 6362 citations) and The New England Journal of Medicine received the most citations (n = 12, 12125 citations). The country and year with the greatest number of publications were the USA (n = 50), and 1998, 1999, and 2000 (n = 7). The most ubiquitous topic was the pathology of EC (n = 66) followed by management of EC (n = 54), and studies related to EC prognosis (n = 44). The most cited manuscripts highlighted the pathology, management, and prognosis of EC and this bibliometirc review provides the most influential references serving as a guide to popular research themes.


Asunto(s)
Bibliometría , Neoplasias Esofágicas , Gastroenterología/estadística & datos numéricos , Publicaciones Periódicas como Asunto/estadística & datos numéricos , Bases de Datos Factuales , Humanos
2.
Chemosphere ; 209: 480-488, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29940531

RESUMEN

There is significant current interest in the application of magnetic (magnetite or maghemite) nanoparticles functionalised with chelating agents for the environmental remediation of metal contaminated waters and solutions. Whilst there is a body of knowledge about the potential remediation efficacy of such engineered nanoparticles from studies involving synthetic solutions of single metals, there is relatively little data involving mixed-metal solutions and virtually no studies about nanoparticle performance in chemically complex environmental solutions representing those to which a scaled-up nanoremediation process might eventually be applied. Therefore, we investigated the ability of diethylenetriaminepentaacetic acid (DTPA)-functionalised, silica-coated maghemite nanoparticles to extract potentially toxic (Cd, Co, Cu) and "non-toxic" (Ca, Mg) metals from solution (initial [metal] = 10 mg L-1; pH range: 2-8) and to extract a wider range of elements (As, Ca, Cd, Co, Cr, Cu, Mg, Na, Pb, Zn) from leachate obtained from 10 different contaminated soils with variable initial pH, (semi-)metal and dissolved organic carbon (DOC) concentrations. The functionalised nanoparticles could extract the potentially toxic metals with high efficiency (in general >70%) from single metal solutions and with efficiencies that were either unaffected or reduced from the soil leachates. Kd values remained high (>500 L kg-1), even for the soil leachate extractions. Our findings show that DOC and relatively high concentrations of non-toxic elements do not necessarily reduce the efficiency of metal contaminant removal by DTPA-functionalised magnetic nanoparticles and thus demonstrate the remediation potential of such particles when added to chemically complex soil-derived contaminated solutions.


Asunto(s)
Restauración y Remediación Ambiental , Nanopartículas de Magnetita/química , Metales Pesados/aislamiento & purificación , Ácido Pentético/química , Contaminantes del Suelo/química , Suelo/química , Contaminantes del Suelo/análisis
3.
Chemosphere ; 183: 519-527, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28570895

RESUMEN

The ability of diethylenetriaminepentaacetic acid (DTPA)-functionalised, silica-coated magnetic nanoparticles to adsorb Pb and Zn from single and bi-metallic metal solutions and from solutions containing dissolved organic carbon was assessed. In all experiments 10 mL solutions containing 10 mg of nanoparticles were used. For single metal solutions (10 mg L-1 Pb or Zn) at pH 2 to 8, extraction efficiencies were typically >70%. In bi-metallic experiments, examining the effect of a background of either Zn or Pb (0.025 mmol L-1) on the adsorption of variable concentrations (0-0.045 mmol L-1) of the other metal (Pb or Zn, respectively) adsorption was well modelled by linear isotherms (R2 > 0.60; p ≤ 0.001) and Pb was preferentially adsorbed relative to Zn. In dissolved organic carbon experiments, the presence of fulvic acid (0, 2.1 and 21 mg DOC L-1) reduced Pb and Zn adsorption from 0.01, 0.1 and 1.0 mmol L-1 solutions. However, even at 21 mg DOC L-1 fulvic acid, extraction efficiencies from 0.01 to 0.1 mmol L-1 solutions remained >80% (Pb) and >50% (Zn). Decreases in extraction efficiency were significant between initial metal concentrations of 0.1 and 1.0 mmol L-1 indicating that at metal loadings between c. 100 mg kg-1 and 300 mg kg-1 occupancy of adsorption sites began to limit further adsorption. The nanoparticles have the potential to perform effectively as metal adsorbents in systems containing more than one metal and dissolved organic carbon at a range of pH values.


Asunto(s)
Benzopiranos/química , Contaminantes Ambientales/análisis , Plomo/análisis , Nanopartículas de Magnetita/química , Ácido Pentético/química , Dióxido de Silicio/química , Zinc/análisis , Adsorción , Sustancias Húmicas , Concentración de Iones de Hidrógeno , Modelos Teóricos , Soluciones , Propiedades de Superficie
4.
Chem Commun (Camb) ; (41): 4338-40, 2006 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-17047860

RESUMEN

We report the first racemic and stereoselective synthesis of cis- and trans-N-alkylaziridines viaN-chloroamines; using this methodology an N-3,4,5-trimethoxybenzylaziridine was synthesised and efficiently cleaved, affording the corresponding NH aziridine in high yield.


Asunto(s)
Aziridinas/química , Cloraminas/síntesis química , Catálisis , Ciclización , Estructura Molecular , Solventes , Estereoisomerismo
5.
Am J Psychiatry ; 152(9): 1343-8, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7653691

RESUMEN

OBJECTIVE: Professional skepticism and concerns regarding diagnostic reliability hinder research in dissociative disorders and multiple personality disorder. The reported frequency of multiple personality disorder in different psychiatric settings ranges from 2.4% to 35%. The authors conducted a replication study of multiple personality disorder ascertainment in women admitted to a state hospital over a 5.5-month period. METHOD: Responses to the Dissociative Experiences Scale and to the Dissociative Disorders Interview Schedule were obtained, along with data on length of stay, county of admission referral, admission commitment status, and discharge diagnoses, for 176 female inpatients in a state hospital. Of 421 women representing 483 consecutive admissions, 121 were discharged before they could be assessed for study, 64 were excluded, 60 declined to participate, 176 enrolled in the study, and 175 completed the research procedures. RESULTS: Twenty-one women (12%) met criteria for multiple personality disorder based on the Dissociative Disorders Interview Schedule; these women were significantly younger than the women without multiple personality disorder. Scores on the Dissociative Experiences Scale of the women with multiple personality disorder (mean = 59.5, SD = 19.6) were significantly higher than the scores of women without multiple personality disorder (mean = 22.5, SD = 20.1), but considerable overlap occurred. There was no significant difference between groups in length of stay or admission status. CONCLUSIONS: The authors conclude that 1) the wide variability in multiple personality disorder detection is partially due to site-specific ascertainment biases and 2) despite its apparent usefulness for screening purposes, the Dissociative Experiences Scale requires more comprehensive evaluation before it can be applied broadly.


Asunto(s)
Trastorno Disociativo de Identidad/epidemiología , Hospitalización , Hospitales Provinciales/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Anciano , Trastorno Disociativo de Identidad/diagnóstico , Femenino , Psiquiatría Forense , Humanos , Tiempo de Internación , Persona de Mediana Edad , North Carolina/epidemiología , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Derivación y Consulta , Reproducibilidad de los Resultados , Factores Sexuales
6.
Org Lett ; 3(8): 1101-3, 2001 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-11348169

RESUMEN

[reaction: see text]. A highly regioselective Friedländer reaction is described. By introduction of a phosphonate group at one of the alpha-carbons of a ketone, regioselectivity can be perfectly controlled.


Asunto(s)
Naftiridinas/síntesis química , Carbono/química , Cetonas/química , Espectroscopía de Resonancia Magnética , Metanol/química , Modelos Químicos , Fosfatos/química
7.
Org Lett ; 2(8): 1081-4, 2000 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-10804559

RESUMEN

[formula: see text] A short synthesis of carbapenem 1 is described. They key step involves the cross-coupling of an enol triflate with an amino-substituted sp3 carbon. This cross-couping, which allows the introduction of the complete side chain in one step, utilizes a stannatrane as the heteroalkyl transfer reagent.


Asunto(s)
Compuestos Bicíclicos con Puentes/química , Carbapenémicos/síntesis química , Resistencia a la Meticilina , Compuestos Orgánicos de Estaño/química , Staphylococcus aureus/efectos de los fármacos
8.
Pharmacotherapy ; 12(4): 278-82, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1355599

RESUMEN

The neuromuscular and cardiovascular effects of intubating doses of pipecuronium 80 micrograms/kg, pancuronium 100 micrograms/kg, atracurium 500 micrograms/kg, and vecuronium 100 micrograms/kg were compared in 62 patients under isoflurane (end-tidal concentration = 0.5-1%) anesthesia. Pipecuronium, pancuronium, and vecuronium had no significant effect on systolic or diastolic blood pressure. In one patient the administration of atracurium resulted in significant hypotension. Heart rate was significantly increased only after the administration of pancuronium. The neuromuscular-blocking effect of pipecuronium and pancuronium appears to be twice as long as that of vecuronium and atracurium. Administration of neostigmine resulted in significantly faster recovery of muscle function in patients receiving vecuronium or atracurium. Although pipecuronium's neuromuscular-blocking effect is similar to that of pancuronium, its lack of cardiovascular effects more closely resembles that of vecuronium.


Asunto(s)
Anestesia General , Hemodinámica/efectos de los fármacos , Isoflurano , Bloqueantes Neuromusculares/farmacología , Unión Neuromuscular/efectos de los fármacos , Adolescente , Adulto , Androstano-3,17-diol/análogos & derivados , Androstano-3,17-diol/farmacología , Atracurio/farmacología , Presión Sanguínea/efectos de los fármacos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Unión Neuromuscular/fisiología , Pancuronio/farmacología , Pipecuronio , Piperazinas/farmacología , Factores de Tiempo , Bromuro de Vecuronio/farmacología
9.
Carbohydr Res ; 330(3): 391-9, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11270818

RESUMEN

Crystalline alpha-D-galacturonic acid monohydrate has been studied by 13C CPMAS NMR and X-ray crystallography. The molecular dynamics were investigated by evaluating 13C spin-lattice relaxation in the rotating frame (T1rho) and chemical-shift-anisotropy properties of each carbon. Only limited molecular motions can be detected in the low frequency (< 10(4) Hz) range by 13C relaxation time measurements (T1rho) and changes of chemical shift anisotropy properties as a function of temperature. X-ray analysis (at both ambient temperature and 150 K) shows that the acid has the usual chair-shaped, pyranose ring conformation, and that the acid and water molecules are linked, through all their O-H groups, in an extensively hydrogen-bonded lattice.


Asunto(s)
Ácidos Hexurónicos/química , Conformación de Carbohidratos , Cristalografía por Rayos X/métodos , Espectroscopía de Resonancia Magnética/métodos , Metilación , Modelos Moleculares , Agua
10.
J Parasitol ; 68(5): 791-5, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6182279

RESUMEN

A hyperimmune serum was raised in rabbits against soluble antigens of Fasciola hepatica metacercariae. This was subsequently absorbed with antigens from adult flukes and examined by immunoelectrophoresis (IEP) and by an indirect fluorescent antibody test (IFAT). When the absorbed antiserum was tested with F. hepatica metacercarial homogenate and adult homogenates by IEP, three distinct arcs appeared against the metacercarial homogenate and none against the adult homogenate. When tested by IFAT against a developmental series of flukes obtained from mice, the absorbed antiserum was positive on surfaces of whole flukes up to 4 days postinfection (PI) and on the tegument of sectioned flukes up to 7 days PI. Thus juvenile-specific antigens were demonstrated in the tegument of young (up to 7 days in mice) F. hepatica.


Asunto(s)
Antígenos de Superficie/análisis , Epítopos/análisis , Fasciola hepatica/inmunología , Animales , Fasciola hepatica/crecimiento & desarrollo , Técnica del Anticuerpo Fluorescente , Inmunoelectroforesis
11.
Res Vet Sci ; 37(2): 219-22, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6505402

RESUMEN

Immature Fasciola hepatica were successfully recovered from the body cavity of cattle from two to 21 days after oral infection. Flukes had penetrated the liver in large numbers by day 7 but there did not appear to be a corresponding reduction in the numbers recovered from the body cavity. Liver pathology showed a typical progressive tissue disruption with a neutrophil and lymphocyte infiltration by day 7 and a marked eosinophil response from day 14. The mesothelium of the liver capsule underwent metaplasia, becoming ultimately highly active and columnar.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Fasciola hepatica/fisiología , Fascioliasis/veterinaria , Hígado/patología , Animales , Bovinos , Enfermedades de los Bovinos/patología , Fascioliasis/parasitología , Fascioliasis/patología , Hígado/parasitología , Locomoción , Linfocitos/citología , Masculino , Neutrófilos/citología , Cavidad Peritoneal/parasitología
12.
Res Vet Sci ; 32(1): 118-20, 1982 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7089374

RESUMEN

Newly excysted juvenile liver flukes were maintained in vitro for 24 hours in the presence of normal or immune rat serum alone, or with the addition of rat cells derived from the peritoneal cavity. Serum was changed and fresh cells added every four hours. Cells were seen to adhere to the flukes in the presence of immune serum throughout the period of incubation, and in the absence of cells this serum induced a precipitate around the flukes. Viability of the flukes, as measured by their transfer to the peritoneal cavity of naive rats and recovery from the livers three weeks later, was unaffected by the treatment.


Asunto(s)
Eosinófilos/inmunología , Fasciola hepatica/inmunología , Animales , Líquido Ascítico/citología , Adhesión Celular , Células Cultivadas , Citotoxicidad Inmunológica , Fasciola hepatica/crecimiento & desarrollo , Sueros Inmunes , Masculino , Ratas
13.
Res Vet Sci ; 29(1): 98-101, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7455360

RESUMEN

Eosinophils present in a mixed population of peritoneal cells, derived from either normal or fluke infected rats, selectively adhered to the tegument of newly excysted Fasciola hepatica in vitro in the presence of immune serum. Adherence occurred independently of complement, was not affected by the age of the sensitising infection and could not be induced by artificially raised antisera to dead fluke antigens.


Asunto(s)
Eosinófilos/inmunología , Fasciola hepatica/inmunología , Animales , Adhesión Celular , Fasciola hepatica/crecimiento & desarrollo , Sueros Inmunes , Masculino , Ratas
14.
Res Vet Sci ; 25(3): 356-9, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-749087

RESUMEN

Goats, sheep and cattle given 1000--1500 eggs of Taenia hydatigena and challenged orally 12 weeks later with 400 Fasciola hepatica metacercariae, showed no evidence of resistance. The fluke burdens were not significantly different from those in control animals.


Asunto(s)
Enfermedades de los Bovinos/inmunología , Cisticercosis/veterinaria , Fascioliasis/veterinaria , Cabras , Enfermedades de las Ovejas/inmunología , Animales , Bovinos , Cisticercosis/inmunología , Cisticercosis/patología , Fasciola hepatica , Fascioliasis/patología , Hígado/patología , Masculino , Ovinos , Enfermedades de las Ovejas/patología
15.
Res Vet Sci ; 25(1): 41-4, 1978 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-705047

RESUMEN

Rats infected three weeks previously with 30 Fasciola hepatica cysts were shown to be highly resistant to oral reinfection, as measured by the recovery of immature flukes from the peritoneal cavity 48 h after challenge and confirmed by liver recoveries three weeks after challenge. Eosinophils were prevalent in the lamina propria of the small intestine three weeks after primary infection and increased markedly after challenge.


Asunto(s)
Eosinófilos/inmunología , Fascioliasis/inmunología , Ratas/inmunología , Animales , Fascioliasis/parasitología , Intestino Delgado/inmunología , Hígado/parasitología , Masculino
16.
Res Vet Sci ; 30(1): 93-8, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7244387

RESUMEN

Intraperitoneal sensitisation of female Piebald Virol Glaxo rats by the migratory immature stages (two-hours-, six-days- and 14-days-old) of the liver fluke Fasciola hepatica protected them from intraperitoneal challenge with living adult flukes three weeks later. Sensitisation with adult fluke antigen and Freund's complete adjuvant had no effect. Flukes attenuated by gamma irradiation (3-8 kiloroentgen), and so prevented from developing beyond the eight to 10 day stage, did not protect against adult challenge. When rats were sensitised orally with metacercariae and challenged with 14-day-old flukes intraperitoneally the challenge flukes were not adversely affected. It is suggested that although 14-day-old flukes can immunise rats adequately, the fact that they are not killed when placed in sensitised rats may be due to the protective effect of tegumental replacement in these flukes before gaining access to, and safety of, the liver site.


Asunto(s)
Fasciola hepatica/inmunología , Fascioliasis/veterinaria , Ratas Endogámicas , Enfermedades de los Roedores/inmunología , Animales , Antígenos/administración & dosificación , Fasciola hepatica/crecimiento & desarrollo , Fascioliasis/parasitología , Femenino , Hígado/parasitología , Ratas , Enfermedades de los Roedores/parasitología
17.
Res Vet Sci ; 30(3): 360-3, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-7255931

RESUMEN

Rats infected with Fasciola hepatica showed an increase in intestinal mast cells which reached a peak between four and six weeks and fell to control levels by week 14. Following a challenge infection sensitised rats showed evidence of a transitory mild intestinal anaphylactic response. The numbers of intestinal eosinophils, already increased as a result of the primary infection, were rapidly supplemented. In previously uninfected rats the majority of flukes penetrated the mid gut region, but in sensitised rats there was a shift towards the caecal end. Resistance to challenge and a pronounced intestinal eosinophil response were evident in previously infected rats irrespective of the presence or absence of detectable serum reaginic antibody. Systemic anaphylaxis, induced by intravenous fluke antigen administration, occurred whether serum reagins could be detected or not.


Asunto(s)
Anafilaxia/etiología , Antígenos/inmunología , Fasciola hepatica/inmunología , Fascioliasis/inmunología , Anafilaxia/inmunología , Animales , Eosinófilos/citología , Intestino Delgado/citología , Intestino Delgado/inmunología , Masculino , Mastocitos/citología , Ratas , Reaginas/biosíntesis
18.
Res Vet Sci ; 20(2): 207-11, 1976 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1265359

RESUMEN

Male and female rats of the inbred Piebald Virol Glaxo ( PVG) and Sprague Dawley (SD) strains were infected with 20 metacercariae of Fasciola hepatica. Three months after infection there was a highly significant difference (P LESS THAN 0-001) in the fluke burden of the two strains. The PVG rats (average 9-4 flukes) were more susceptible than the SD strain (average 2-8 flukes). The PVG males (11-6 flukes) were also found to be significantly more susceptible than the PVG females (average 7-2 flukes) whereas the sex of the SD rats did not affect the fluke burdens significantly. Seven to eight months after infection the PVG rats had eliminated their flukes. These 'self cured' PVG rats were significantly resistant to oral challenge with 20 metacercariae. In marked contrast the SD rats had not eliminated their flukes at the termination of the experiment 12 months after infection.


Asunto(s)
Fascioliasis/parasitología , Inmunidad Activa , Animales , Conductos Biliares/parasitología , Fascioliasis/inmunología , Heces/parasitología , Femenino , Masculino , Recuento de Huevos de Parásitos , Ratas , Ratas Endogámicas , Factores de Tiempo
19.
Res Vet Sci ; 26(2): 259-60, 1979 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-262614

RESUMEN

Attempts were made to immunise rats against Fasciola hepatica using the culture products obtained from the in vitro cultivation of newly excysted metacercariae. Three culture regimes were chosen: (1) medium NCTC 135 for 48 h (2) NCTC 135 + 20 per cent fetal calf serum (FCS) for 48 h (3) NCTC 135 + 20 per cent FCS for 14 days. The used culture medium from each of these regimes was concentrated, mixed with adjuvant and injected subcutaneously into rats. Similarly treated unused culture media was used in control rats. The rats were challenged with an oral dose of 20 F hepatica metacercariae 35 days later and autopsied 96 days after the start of the experiment. The fluke burdens in those rats which had received the culture antigens did not differ significantly from those in the control groups.


Asunto(s)
Fascioliasis/prevención & control , Inmunización/métodos , Ratas/inmunología , Animales , Antígenos/inmunología , Fasciola hepatica , Femenino
20.
Res Vet Sci ; 28(2): 250-3, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7414072

RESUMEN

The survival rate of rats given potentially lethal doses of 7.6 X 10(8) to 10(9) Salmonella dublin intraperitoneally was enhanced in those which had been infected six weeks previously with 10(2) S dublin by the same route. Fasciola hepatica given six weeks before or one week after 10(2) S dublin did not alter the survival rate of rats reinfected with S dublin. However high levels (10(4) to 10(6) per g) of S dublin persisted in the tissues and faeces of fluke-infected but not of fluke-free rats. Agglutinating antibody responses to S dublin were unimpaired in fluke-infected rats but cutaneous delayed hypersensitivity reactions were slightly reduced. the humoral agglutinating antibody response may be important for survival of the host but other responses may be necessary for elimination of S dublin from the tissues.


Asunto(s)
Fascioliasis/veterinaria , Ratas , Enfermedades de los Roedores/inmunología , Salmonelosis Animal/inmunología , Aglutininas/análisis , Animales , Fasciola hepatica , Fascioliasis/inmunología , Enfermedades de los Roedores/microbiología , Salmonella/inmunología , Salmonella/aislamiento & purificación , Salmonelosis Animal/microbiología , Pruebas Cutáneas
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