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991.
OBJECTIVE: To evaluate awareness and knowledge of cigarette filter ventilation in a national probability sample of smokers of Ultra-light, Light, and regular cigarettes. DESIGN: Random-digit-dialling and computer-assisted telephone interviewing was used on a probability sample of daily cigarette smokers (ages 18 and above). SUBJECTS AND SETTING: 218 Smokers of Ultra-light cigarettes, 360 smokers of Light cigarettes, and 210 smokers of Regular cigarettes living in the continental United States. MAIN OUTCOME MEASURES: Percentage of respondents indicating knowledge of the presence of filter vents and the consequences of behavioural blocking of vents. RESULTS: Many smokers had not heard about or seen the filter holes: 43% (95% CI = 36 to 50%) of smokers of Ultra-lights, 39% (95% CI = 34 to 44%) of smokers of Lights, and 47% (95% CI = 40 to 54%) of smokers of Regulars. About two in three smokers either did not know of the existence of rings of small holes on the filters of some cigarettes, or did not know that blocking increases tar yields: 69% (95% CI = 63 to 75%) of Ultra-lights, 66% (95% CI = 61 to 71%) of Lights, and 69% (95% CI = 63 to 75%) of Regulars. CONCLUSIONS: Smokers are generally unaware of the presence and function of filter vents-a major design feature subject to behavioural blocking by smokers and now present on most cigarettes in the United States. Smokers and policy-makers need to be informed about the presence of filter vents and how vent blocking increases tar and nicotine yields from ostensibly very low-yield cigarettes.  相似文献   
992.
993.
At a period of fundamental review of the health care system, it is timely to re-assess one of medicine's most intractable problems--the treatment of addictions. The apparently insoluble dilemmas posed by the acute and chronic withdrawal syndromes underlie universally high drop-out and relapse rates. In a decade of HIV and AIDS infection, poly-substance addiction, potent street drugs, and ossified treatment strategies, it is urgent that policy formulators investigate seriously a flexible system of non-pharmacological transcranial electrostimulation treatment, based on its record of rapid, safe, and cost-effective detoxification in several countries, as one innovative contribution to the challenges presented by addiction in the 1990s. This is a brief report of the introduction of NeuroElectric Therapy (NET) into Germany, describing the responses of the first 22 cases. The daily progress of a heroin addict and a methadone addict are detailed: both were treated as outpatients for 8 hours daily, for 7 and 10 days respectively.  相似文献   
994.
995.
Biologic effects of the hepatocarcinogenic mycotoxin aflatoxin B1 are principally induced by one of its metabolites, the exo-aflatoxin B1 epoxide which produces both DNA and protein adducts in vivo. Detoxication of the exo-aflatoxin B1 epoxide can be mediated in part by glutathione S-transferases whose induction could be important in chemoprotection interventions. Thus, biomarkers of the enzymatic conjugation of exo-aflatoxin B1 epoxide with glutathione may be important indices of protection against the toxic effects of this agent. Since glutathione conjugates undergo further metabolic processing in vivo to yield mercapturic acids, increased urinary excretion of exo-aflatoxin B1 mercapturate could be expected during chemoprotection intervention. To determine if this mercapturic acid could be used as a biomarker, techniques for its specific measurement were developed using monoclonal antibody immunoaffinity chromatography and reverse phase high-performance liquid chromatography with ultraviolet absorbance and mass spectral detection. First, a synthetic exo-aflatoxin B1 mercapturate was characterized using mass spectrometry, ultraviolet absorbance, circular dichroism spectrometry, and chemical derivatization. In vivo metabolite characterization was then facilitated by comparison with the synthetically prepared exo-aflatoxin B1 mercapturate and both aflatoxin B1-glutathione conjugate diastereoisomers. In rats, 1% of the aflatoxin dose was excreted as exo-aflatoxin B1 mercapturate within 24 h. The finding that exo-aflatoxin B1 mercapturate was excreted in urine in a dose-dependent manner provides the basis for investigating its applicability as a biomarker of glutathione S-transferase status in aflatoxin chemoprotection studies.  相似文献   
996.
We used plants as an in vivo pathogenesis model for the identification of virulence factors of the human opportunistic pathogen Pseudomonas aeruginosa. Nine of nine TnphoA mutant derivatives of P. aeruginosa strain UCBPP-PA14 that were identified in a plant leaf assay for less pathogenic mutants also exhibited significantly reduced pathogenicity in a burned mouse pathogenicity model, suggesting that P. aeruginosa utilizes common strategies to infect both hosts. Seven of these nine mutants contain TnphoA insertions in previously unknown genes. These results demonstrate that an alternative nonvertebrate host of a human bacterial pathogen can be used in an in vivo high throughput screen to identify novel bacterial virulence factors involved in mammalian pathogenesis.  相似文献   
997.
The functioning of the major subsystems of the speech production apparatus of a 12 year old female with Moebius syndrome was investigated using a battery of perceptual and physiological instrumental measures. Perceptual tests administered included: The Assessment of Intelligibility of Dysarthric Speech; the Frenchay Dysarthria Assessment; and a perceptual analysis of a speech sample based on a reading of the Grandfather Passage. Instrumental procedures included: spirometric and kinematic analysis of speech breathing; electroglottographic and aerodynamic evaluation of laryngeal function; nasometric assessment of velopharyngeal function; and evaluation of lip and tongue function using a variety of strain-gauge and pressure transducers. Consistent with the pathophysiological basis of Moebius syndrome, the major dysfunctions of the speech production mechanism were found at the level of the articulatory valve. Somewhat unexpectedly, however, impaired function was also identified at the level of the velopharyngeal and laryngeal valves by both the perceptual and instrumental assessments and at the level of the respiratory system by the physiological analysis alone. The results are discussed with reference to the neurological basis and clinical features of Moebius syndrome. The implications of the findings for the treatment of congenital dysarthria associated with Moebius syndrome are also discussed. The advantage of instrumental analysis over perceptual assessments in defining treatment goals for children with congenital dysarthria is highlighted.  相似文献   
998.
999.
PURPOSE: To assess the computed tomographic (CT) and histologic findings of intrathoracic lymphoproliferative disease (LPD) associated with the Epstein-Barr virus (EBV). MATERIALS AND METHODS: The authors retrospectively reviewed the CT scans of the chest and the pathologic specimens obtained in 24 patients with histologically proved intrathoracic LPD and with positive serologic findings or immunohistochemical staining for EBV. Five patients had acquired immunodeficiency syndrome (AIDS); one had common variable immune deficiency; and 18 were receiving immunosuppressive therapy for heart, lung, or heart-lung (n =15) or bone marrow (n = 2) transplantation and vasculitis (n = 1). RESULTS: Final diagnoses included malignant lymphoma (n = 15), polyclonal LPD (n = 8), and hyperplasia of bronchus-associated lymphoid tissue (n = 1). CT findings included multiple nodules (n = 21), lymphadenopathy (n = 9), areas of groundglass opacification (n = 8), septal thickening (n = 7), consolidation (n = 5), pleural effusion (n = 4), and solitary endobronchial lesion (n = 2). The nodules were 2-4 cm in diameter, involved mainly the middle and lower lung zones, and frequently had a predominantly peribronchovascular (n = 15) or subpleural (n = 14) distribution. CONCLUSION: EBV-associated LPD may range from benign lymphoid hyperplasia to high-grade lymphoma. The most common CT manifestation consists of multiple nodules, frequently in a predominantly peribronchovascular or subpleural distribution.  相似文献   
1000.
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