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981.
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
982.
983.
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
984.
LG Rahme MW Tan L Le SM Wong RG Tompkins SB Calderwood FM Ausubel 《Canadian Metallurgical Quarterly》1997,94(24):13245-13250
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
985.
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
986.
987.
SM Farrington J Lin-Goerke J Ling Y Wang JD Burczak DJ Robbins MG Dunlop 《Canadian Metallurgical Quarterly》1998,63(3):749-759
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
988.
989.
AM Boot MA Engels GJ Boerma EP Krenning SM De Muinck Keizer-Schrama 《Canadian Metallurgical Quarterly》1997,82(8):2423-2428
Adults with childhood onset GH deficiency (GHD) have reduced bone mass, increased fat mass, and disorders of lipid metabolism. The aim of the present study was to evaluate bone mineral density (BMD), bone metabolism, body composition, and lipid metabolism in GHD children before and during 2-3 yr of GH treatment (GHRx). Forty children with GHD, mean age 7.9 yr, participated in the study of bone metabolism and body composition; and an additional group of 17 GHD children, in the study of lipid metabolism. Lumbar spine BMD, total body BMD, and body composition were measured with dual-energy x-ray absorptiometry. Volumetric BMD (bone mineral apparent density, BMAD) was calculated to correct for bone size. BMD, BMAD, lean tissue mass, bone mineral content, fat mass, and percentage body fat were expressed as SD scores (SDS), in comparison with normative data of the same population. Lumbar spine BMD and BMAD and total body BMD were all decreased at baseline. All BMD variables increased significantly during GHRx, lumbar spine BMD SDS, already after 6 months of treatment. Lean tissue mass SDS increased continuously. Bone mineral content SDS started to increase after 6 months GHRx. Fat mass SDS decreased during the first 6 months of GHRx and remained stable thereafter. Biochemical parameters of bone formation and bone resorption did not differ from normal at baseline and increased during the first 6 months of GHRx. Serum 1,25 dihydroxyvitamin D increased continuously during GHRx, whereas PTH and serum calcium remained stable. Lipid profile was normal at baseline: Atherogenic index had decreased and apolipoprotein A1(Apo-A1) had increased after 3 yr of treatment. In conclusion, children with GHD have decreased bone mass. BMD, together with height and lean tissue mass, increased during GHRx. GHRx had a beneficial effect on lipid metabolism. 相似文献
990.
In this study, five different bacteria with their different strains were isolated and characterized. Contact angles were measured by a captive-bubble technique. Surface-free energies were calculated from the contact angles. Hydrophobicities also were evaluated by rho-xylene adhesion. The zeta potentials and surface charges of the bacteria were obtained. The contact angles of the gram-positive bacteria and gram-negative bacteria were within the range of 48 degrees-69 degrees and 43.5 degrees-55 degrees, respectively, while corresponding surface-free energies were in the limits of 45.4-51.6 erg/cm-2 and 51.7-61.8 erg/cm-2, respectively. The rho-xylene adhesions were parallel to hydrophobicities defined by contact angles, and 32.2-80.3% and 2.3-36.6% for the gram-positive bacteria and gram-negative bacteria, respectively. The zeta potentials for these bacteria were from -650.2 to +17.5 mV and from -159.6 to -6.0 mV, respectively. Most of the bacteria were negatively charged, except the CNS-2 and CPS-1 strains. In the second part of the study, attachment of these bacteria to Vicryl sutures and their DMAEMA and AAc plasma-treated forms were investigated. Hydrophobic bacteria attached more to hydrophobic Vicryl sutures. Both plasma treatments caused significant drops in bacterial attachment in most cases. Effects of AAc plasma treatment were more pronounced. 相似文献