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1.
Am Surg ; 59(5): 273-7, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8489092

RESUMEN

Thirty patients with chronic upper abdominal pain and no evidence of cholelithiasis were entered into this study. All had negative ultrasonography of the gallbladder, and most had a host of other negative investigations. These patients were referred to a surgeon to evaluate the possibility of atypical biliary colic associated with chronic acalculous cholecystitis. All patients underwent cholecystokinin-stimulated cholescintigraphy and were offered cholecystectomy if the ejection fraction was less than 35 per cent. Of the 30 patients, 27 (90%) had pathologically abnormal gallbladders. Follow-up averaged over 1 year (13.2 mo), and relief of symptoms occurred in 28 (94%). The authors conclude that in appropriately selected patients with symptoms of biliary colic (typical or atypical) and no evidence of cholelithiasis, a cholecystokinin-stimulated cholescintigram is a significant help in predicting not only which patients have gallbladder disease, but also how likely cholecystectomy is to result in an improvement in their symptoms.


Asunto(s)
Colecistitis/diagnóstico por imagen , Sincalida , Adolescente , Adulto , Colecistectomía , Colecistitis/cirugía , Colecistografía , Colelitiasis/diagnóstico , Enfermedad Crónica , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor , Cintigrafía
2.
J Chromatogr Sci ; 28(8): 393-9, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2229269

RESUMEN

Eight compounds from a Kentucky 1R4F reference cigarette smoke condensate have been determined by selected ion monitoring-mass spectrometry (SIM-MS) to confirm the validity of multidimensional gas chromatography (MDGC) as a quantitative tool in complex mixture analyses. Four electrostatically precipitated smoke condensate samples of 100 cigarettes each are dissolved individually in 25 mL of 2-propanol. The 2-propanol contains two methyl esters (C8 and C14) and seven deuterium-labeled compounds used as internal standards (IS). Analysis of the compounds of interest, pyridine; acetamide; acrylamide; phenol; o-, m-, and p-cresol; and quinoline, is accomplished by using two heartcuts. Heartcut times of the MDGC analysis are selected such that at least one IS is transferred with each group of compounds being analyzed. This study shows that the MDGC technique previously developed and described can be used for quantitative analyses. A comparison is made between the two types of internal standards. The results obtained for both types of internal standards agree within 20% of each other, on the average, with higher standard deviations for approximately 60% of the compounds where methyl esters are used as internal standards.


Asunto(s)
Cromatografía de Gases/métodos , Espectrometría de Masas/métodos , Nicotiana/análisis , Plantas Tóxicas , Humo/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Kentucky
3.
J Chromatogr Sci ; 28(8): 432-6, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2229270

RESUMEN

A simple method has been developed to separate and quantitate monovalent ionic species in mainstream cigarette smoke aerosols based on ion chromatography (IC) with conductivity detection. The method entails collecting the smoke aerosol particulate phase by electrostatic precipitation, dissolving the smoke condensate in methanol (MeOH), and separating the ionic species on either a cation- or anion-exchange column. The method has been applied to the analysis of smoke aerosols from two cigarettes, 1R4F Kentucky Reference cigarettes and a new cigarette that heats but does not burn tobacco. The predominant cations in smoke aerosols from 1R4F Kentucky Reference and the new cigarettes are sodium (Na+), ammonium (NH4+), and potassium (K+) ions; the predominant anions are acetate (AcO-) and formate (HCOO-). Trace amounts of chloride (Cl-), nitrite (NO2-), and nitrate (NO3-) ions are also present.


Asunto(s)
Aniones/análisis , Cationes/análisis , Cromatografía por Intercambio Iónico/métodos , Nicotiana/análisis , Plantas Tóxicas , Humo/análisis , 1-Propanol , Aerosoles/análisis , Amoníaco/análisis , Potasio/análisis , Sodio/análisis
4.
J Assoc Off Anal Chem ; 73(4): 610-5, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2211484

RESUMEN

A method is described for determining major constituents in the smoke of a cigarette that heats, but does not burn, tobacco. Dual, simultaneous separations are performed in a single gas chromatographic oven to determine water, glycerol, nicotine, and propylene glycol in a rapid and cost-effective manner. A materials balance of new cigarette smoke total particulate matter was attempted from both Cambridge filter and electrostatic precipitation smoke collection data. Serious deficiencies were found when Cambridge filter smoke collection was applied for this purpose. Electrostatic precipitation smoke collection eliminated these problems. The data obtained by electrostatic precipitation smoke collection indicate that water, glycerol, nicotine, and propylene glycol make up about 94% of new cigarette smoke total particulate matter.


Asunto(s)
Humo/análisis , Fumar , Filtración , Glicerol/análisis , Indicadores y Reactivos , Kentucky , Nicotina/análisis , Propilenglicol , Glicoles de Propileno/análisis , Estándares de Referencia , Agua/análisis
5.
J Assoc Off Anal Chem ; 73(4): 605-9, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2211483

RESUMEN

The design of a new cigarette that heats rather than burns tobacco calls for modifications to the Federal Trade Commission (FTC) method for analytical smoking. These changes include eliminating sample conditioning at 75 degrees F and 60% RH, exercising greater care in lighting cigarettes, and smoking cigarettes to self-extinguishment rather than to a predetermined butt length as a measure of complete consumption. By several gross analytical measures, smoke condensate from the new cigarette differs substantially from that of tobacco-burning cigarettes. This is inferred from the lack of coloration of smoke condensate collected on Cambridge filters. Elemental analysis demonstrates reduced carbon and nitrogen content concurrent with increased hydrogen. Thermogravimetric analysis shows almost quantitative weight loss at Tmax = 220 degrees C. Ultraviolet (UV) spectrophotometric analysis shows greatly reduced levels of tobacco-derived smoke components and qualitative differences in chemical entities being measured. By design, the heat required for smoke formation is supplied by a carbon heat source embedded in the cigarette tip. Tobacco contained in the cigarette is not burned and is exposed to temperature less than 300 degrees C. Thus, it is apparent (1) that smoke from the new cigarette contains little or no "tar" as tar is classically defined, and (2) that the FTC method even as modified to account for cigarette design differences is appropriate only for determination of nicotine and carbon monoxide yielded from this cigarette.


Asunto(s)
Humo/análisis , Fumar , Carbono/análisis , Concentración de Iones de Hidrógeno , Indicadores y Reactivos , Nitrógeno/análisis , Espectrofotometría Ultravioleta , Temperatura
6.
J Chromatogr ; 505(2): 365-74, 1990 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-2355067

RESUMEN

Cigarette smoke condensate is a complex chemical matrix and determination of phenolic compounds in it frequently requires extensive and laborious sample preparation. By utilizing derivatization techniques and capillary column gas chromatography with mass spectrometry in the selected-ion mode, separation and quantitation of selected phenolic compounds found in mainstream cigarette smoke can be accomplished with minimal sample preparation. This method has been used to determine concentrations of phenol, o-cresol, m-cresol, p-cresol, catechol, resorcinol and hydroquinone in cigarette smoke condensate from a number of commercially available cigarettes and a new cigarette which heats, but does not burn, tobacco. Unlike tobacco-burning cigarettes, levels of the phenolic compounds in the new cigarette smoke are at or below the detection limits for most of the compounds. This result is attributed to the unique design of the new cigarette.


Asunto(s)
Nicotiana , Fenoles/análisis , Plantas Tóxicas , Humo/análisis , Fenómenos Químicos , Química , Cromatografía de Gases y Espectrometría de Masas
7.
J Chromatogr ; 503(2): 359-68, 1990 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-2185256

RESUMEN

A cryogenic trapping method with isotope dilution gas chromatography-mass spectrometry analysis has been developed for the determination of benzene, toluene, styrene and acrylonitrile in mainstream vapor phase cigarette smoke. The method is simple, direct, and quantitative. Vapor phase samples are collected cryogenically in a series of four traps following removal of the particulate phase with a Cambridge filter pad. For all four analytes, 75-85% of the total amounts recovered were found in the initial trap and less than 1% in the final trap. Assessment of instrumental precision by multiple injections of a sample gave relative standard deviations of less than 2%. Linear calibration for all analytes over the analysis range gave an r2 value greater than 0.99 with average relative standard deviations at the mean ranging from 1.4 to 8.2%. The cigarettes analyzed include a reference cigarette (Kentucky 1R4F), a commercial ultra-low "tar" mentholated cigarette, and two cigarettes that heat but do not burn tobacco. The values determined for the four analytes in the 1R4F samples are comparable to reported values of similar cigarettes. The cigarettes which heat rather than burn tobacco yield less of all four analytes compared to the other cigarettes in the study.


Asunto(s)
Acrilonitrilo/análisis , Benceno/análisis , Nicotiana , Nitrilos/análisis , Plantas Tóxicas , Humo/análisis , Estirenos/análisis , Tolueno/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Técnica de Dilución de Radioisótopos
8.
Hawaii Med J ; 48(11): 462, 483-4, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2592193

RESUMEN

The abuse of cocaine has increased dramatically over the past 15 years. Studies performed by the National Institute of Drug Abuse (NIDA) revealed at least a five-fold increase in its use from the mid-'70s to the late '80s. Recent reports indicated that at least 30 million Americans have tried cocaine and that 17% of high-school seniors have used cocaine on more than one occasion. It is estimated that there are 5,000 new users each day. Prevalence studies show that current use (use within the past 30 days) has increased to include at least 6 million Americans. Whereas studies over the past 2 years suggest some slowing of the dramatic increase mentioned above, the increase in the use of crack cocaine continues unabated. Recent political events in Central and South America are a clear reflection of the expanding demand for cocaine in both North America and Europe.


Asunto(s)
Cocaína , Trastornos Relacionados con Sustancias/terapia , Animales , Terapia Combinada , Vías de Administración de Medicamentos , Humanos , Trastornos Relacionados con Sustancias/fisiopatología , Trastornos Relacionados con Sustancias/psicología
9.
Hawaii Med J ; 48(11): 491-2, 494-5, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2574167

RESUMEN

The individual who suffers from chemical dependency has unique physiological and psychological conditions that make the management of acute and chronic disabling conditions challenging, frustrating or stressful, depending upon the experience of his primary attending physician. Several general principles are helpful in this situation. Special conditions, such as tolerance to opiate analgesics, and methadone maintenance, require special attention. The desire to treat the person who has an admitted or suspected history of chemical dependence presents conflicting interests for the attending physician. While there is the desire to provide the best possible care for any patient, this must be balanced against contributing to the patient's primary problem with drugs, and perhaps worse yet, the fear of being used by the patient to provide him with drugs to support his drug habit. The fear of dealing with a patient who is "running a scam" to obtain prescription drugs, or the anxiety of having to deal with an overly zealous DEA agent, further complicates the physician's role in the care of these parties.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Dolor/prevención & control , Trastornos Relacionados con Sustancias/fisiopatología , Actitud del Personal de Salud , Humanos , Rol del Médico
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