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61.
The professional literature is limited in its coverage of the challenges of clinical and counseling internship training in rehabilitation settings. The characteristics of the patient population, the goals of rehabilitation, and the team approach require the development of professional role behaviors appropriate to these facilities. The present article explores relevant issues and presents suggestions for augmenting training programs to make them congruent with the distinctive aspects of rehabilitation. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Microiontophoretic drug application and extracellular recording techniques were used to evaluate the effects of the selective metabotropic glutamate receptor (mGluR) agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylate(1S,3R-ACPD) on dopamine (DA) neurons in the substantia nigra zona compacta (SNZC) of chloral hydrate-anesthetized rats. 1S,3R-ACPD had a biphasic effect on the firing rate of DA cells, initially decreasing, then increasing the firing rate. 1S,3R-ACPD also increased the burst-firing activity of DA neurons. Application of the ionotropic receptor (iGluR) agonists (R,S)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) or N-methyl-D-aspartate (NMDA) increased the firing rates of neurons which had responded to 1S,3R-ACPD, indicating that mGluRs and iGluRs reside on the same neurons. The initial inhibitory period was not antagonized by systemic haloperidol or iontophoretic bicuculline, indicating a lack of DA or gamma-amino-n-butyric acid (GABA) involvement in this effect. Combined application of the AMPA antagonist, 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(f)quinoxaline (NBQX), and the NMDA antagonist, (I)-3-(2-carboxypiperazin-4-yl)propyl-1-phosphoric acid (CPP), at currents which antagonized AMPA and NMDA, did not antagonize either the inhibitory or excitatory effects of 1S,3R-ACPD. Application of the metabotropic antagonist (S)-4-carboxy-phenylglycine antagonized both the inhibitory and excitatory effects of 1S,3R-ACPD. These results indicate that mGluRs may play a role in the modulation of dopaminergic activity in the SNZC.  相似文献   
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Alveolar macrophages (AMs) were analyzed for ability to support replication of the intracellular bacterium Francisella tularensis live vaccine strain (LVS). AM supported in vitro growth (2 to 3 logs over 5 days) of LVS with a doubling time of 8 +/- 0.8 h. AMs were analyzed for responsiveness to rIFN-gamma for destruction of this lung pathogen. AM treated with 50 U/ml rIFN-gamma allowed early growth of bacteria (six doublings over 48 h) but between 48 and 96 h rIFN-gamma-treated AM eliminated 1.5 logs of LVS. AMs were sensitive to effects of rIFN-gamma; as little as 5 U/ml rIFN-gamma stimulated AM antimicrobial activity, with half-maximal activity 0.3 U/ml. rIFN-gamma-induced antimicrobial effects in AM correlated with amount of nitrites produced, but nitric oxide played only a minimal role in antibacterial effects induced in AM, because NG-MMLA (specific inhibitor of L-arginine-dependent nitric oxide production) failed to block antimicrobial activity of IFN-gamma-stimulated AM. IL-10, TGF-beta 1, and IFN-alpha (cytokines known to regulate effector functions of activated macrophages) also did not block anti-F. tularensis activity of IFN-gamma-stimulated AM. Reactive oxygen metabolites, depletion of tryptophan, and sequestration of iron did not contribute to anti-F. tularensis activity because addition of superoxide dismutase or catalase, excess iron, or tryptophan to IFN-gamma-treated AM did not reverse the anti-F. tularensis activity observed in these cells. Regulation of AM effector activity differed from that of other macrophage populations, in that while rIFN-gamma-stimulated AM produced TNF-alpha (100 U/ml at 72 h), TNF-alpha was not required as a costimulator for induction of antimicrobial activities by rIFN-gamma because anti-TNF-alpha treatment of rIFN-gamma-stimulated AM blocked TNF-alpha but had no effect on either production of nitrites or anti-F. tularensis activity.  相似文献   
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Plasma methadone concentrations and its main metabolite D,L-2-ethylidiene-1,5-dimethyl-3,5-diphenylpyrrolidine (EDDP) were determined in 93 patients under methadone maintenance treatment to assess their relationship with heroin use and opioid withdrawal symptoms. Neither plasma concentrations of methadone nor EDDP were significantly different when patients that used heroin in last 3 months were compared with those testing negative for this drug (methadone, 355 +/- 217 versus 369 +/- 216 ng/ml, t = 0.29, P = NS; EDDP, 49 +/- 28 versus 54 +/- 40 ng/ml, t = 0.51, P = NS). No correlation between opioid withdrawal scale scores and plasma concentrations of methadone (r = 0.02, P = NS) and EDDP (r = -0.14, P = NS) was found. Therapeutic drug monitoring during methadone maintenance seems to be useful for assessing compliance with treatment but not for predicting heroin use and subjective withdrawal symptoms.  相似文献   
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Our understanding of the molecular pathology underlying the development and progression of ductal pancreatic cancer has been revolutionised during the last 5 years due to the spectacular development of novel molecular biological techniques. In the present article, we describe key molecular alterations of sporadic and inherited ductal pancreatic cancer. Overexpression of growth factors and growth factor receptors are present in a significant proportion of this tumour type. Mutation of the K-ras oncogene, and disruption of p53 or p16 tumour suppressor gene abrogates the control of the cyclin-dependent kinases (cdk) and retinoblastoma (Rb) gene pathway, causing continuous growth of the pancreatic tumour. Inactivation of the SMAD4 tumour suppressor gene leads to loss of the inhibitory influence of the transforming growth factor beta signalling pathway. Lost or decreased expression of retinoid receptors and failure of telomerase activity may play a role in pancreatic carcinogenesis. Tumour-associated proteinases, matrix metalloproteinases and plasminogen activators are reported to be involved in pancreatic cancer invasion and metastasis. Furthermore, the cytogenetic changes in this cancer are summarised. This molecular pattern distinguishes pancreatic cancer from other epithelial tumours and represents a promising basis for the development of diagnostic and other clinical applications.  相似文献   
68.
Determination of microgram quantities of protein in the Bradford Coomassie brilliant blue assay is accomplished by measurement of absorbance at 590 nm. However, as intrinsic nonlinearity compromises the sensitivity and accuracy of this method. It is shown that under standard assay conditions, the ratio of the absorbances, 590 nm over 450 nm, is strictly linear with protein concentration. This simple procedure increases the accuracy and improves the sensitivity of the assay about 10-fold, permitting quantitation down to 50 ng of bovine serum albumin. Furthermore, protein assay in presence of up to 35-fold weight excess of sodium dodecyl sulfate (detergent) over bovine serum albumin (protein) can be performed. A linear equation that perfectly fits the experimental data is provided on the basis of mass action and Beer's law.  相似文献   
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