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61.
The objective of this study was to develop and test a brief and unobtrusive instrument to detect exaggeration and simulation in whiplash syndrome. The instrument consists of eight scenarios with ten response options that have to be ordered according to how easy a behavior is to perform. Twenty-five simulating and 25 non-simulating patients with whiplash syndrome of grades 2 and 3 according to the Quebec Task Force classification as well as 25 simulating and 25 non-simulating controls completed the instrument. In a cross-validation study 20 controls and 20 patients participated. Malingering and exaggeration scores were determined for each subject and patient. The scores were summed up and compared across malingering and exaggerating subjects and controls and cut-off values were determined to classify the patients. T-tests and a discriminant analysis were used to determine classification accuracy. The instrument correctly identified 94% of the simulators and 84% of the exaggerators in both samples. This brief and unobtrusive instrument can detect exaggeration and simulation in whiplash syndrome.  相似文献   
62.
Diversity and evolution of the envelope gene of dengue virus type 1   总被引:11,自引:0,他引:11  
The genetic diversity and phylogenetic relationships of a collection of strains of dengue virus type 1 (DV-1), isolated from different parts of the world, were investigated. Phylogenetic trees derived from the complete sequence of the E gene of 44 strains suggested the existence of five genetic types defined by a maximum nucleotide divergence within each group of 6%. The 22 strains from America were classified into a single genetic type that included strains associated either with classical dengue or hemorrhagic dengue episodes. Using a maximum likelihood procedure based on a single rate with dated tips model and substitution rates calculated at the third codon position, evolution of the five DV-1 genotypes was shown to conform to a molecular clock. The average rate of evolution was estimated to be approximately 16.2 x 10(-4) substitutions/third codon position site/year. Using this estimate, divergence among the DV-1 genotypes was calculated to have occurred approximately 100 years ago. Very low average value of the ratio of nonsynonymous-to-synonymous nucleotide substitutions, relative to the respective sites (0.046), indicated that the evolution of the E gene of the DV-1 is subject mostly to purifying selection.  相似文献   
63.
Objective To test the hypothesis that questionnaire organization affects the recall of antimalarial drugs utilization. Setting Maputo, Mozambique. Methods Treatment of last malaria episode was assessed using two alternative versions (A and B) of a questionnaire, which differed only by the order each proposed drug was presented in the response options (version A: quinine and most frequently used drugs presented first; version B: less frequently used drugs first and quinine at the end). Questionnaires A or B were randomly assigned to each of 32 classes in a private University in Maputo, Mozambique. Within each classroom all subjects received the same questionnaire version, and a similar number of participants fulfilled questionnaires A (n = 249) and B (n = 255). Main outcome measures Recall of the antimalarial drugs utilization in a previous malaria episode. Results Mefloquine and clindamycin were not used by any subject in the last malaria episode. The overall recall of quinine utilization was higher with questionnaire A (19.5% vs. 11.6%, P = 0.006) and the use of artemisinine/artesunate was reported more frequently by subjects inquired with questionnaire B (16.5% vs. 7.3%, P = 0.012). When considering subjects reporting more than one malaria episode, the recall of quinine utilization was higher with questionnaire A (20.0% vs. 6.4%, P = 0.004), and the use of artemisinine/artesunate was reported more frequently by subjects inquired with questionnaire B (18.3% vs. 8.8%, P = 0.069). No differences were observed among those having had only one malaria episode, neither for quinine (22.2% vs. 20.0%, P = 0.807) or artemisinine/artesunate (5.0% vs. 6.7%, P = 0.701). Conclusion The structure of the questionnaire used to collect self-reported information about antimalarial treatments influences the recall, even when close ended questions asking for specific drugs are used. Among subjects having been treated for malaria more than once, the first antimalarial drugs being asked were more likely to be selected.  相似文献   
64.
Racemic CPCCOEt ((1aRS,7aRS)-2-hydroxyimino-1a, 2-dihydro-1H-7-oxacyclopropa[b]naphthalene-7a-carboxylic acid ethyl ester, (+/-)-1) derivatives have been shown to be subtype-selective metabotropic glutamate (mGlu) 1 receptor antagonists (Annoura et al. Bioorg. Med. Chem. Lett. 1996, 6, 763-766). The optical isomers of (+/-)-1 have been separated by chromatography on a chiral stationary phase. The absolute configuration at the C-1a and C-7a positions was determined using X-ray crystallography of an amide derivative with the methyl ester of L-phenylalanine (L-PheOMe) ((+)-6). In a phosphoinositol (PI) turnover assay at the cloned human mGlu1b receptor, (-)-1 and the new amide derivatives (-)-5 and (-)-6, all of which have (1aS,7aS)-stereochemistry on the chromane ring system, showed IC(50) values of 1.5, 0.43, and 0.93 microM, respectively. In contrast, (+)-1 and the new amide derivatives (+)-5 and (+)-6were found to be inactive up to a concentration of 30 microM indicating a selectivity for the (-)-enantiomers of at least 70-fold. In a previous study (Litschig et al. Mol. Pharmacol. 1999, 55, 453-461) we demonstrated using site-directed mutagenesis that the interaction site of (+/-)-1 is located in the transmembrane (TM) domain of hmGlu1b. To suggest a plausible binding mode of (-)-1, we have built a molecular mechanics model of the putative seven TM domain of hmGlu1 based on the alpha-carbon template of the TM helices of rhodopsin. A receptor docking hypothesis suggests that the OH of T815 (TMVII) comes in close contact with the oxime OH of (-)-1 and (-)-5, whereas no such close interactions could be demonstrated by docking of (+)-1.  相似文献   
65.

Aim

To evaluate the impact of contrast-enhanced computed tomography colonography (CE-CTC) on laparoscopic surgery planning in patient with stenosing colorectal cancer.

Materials and methods

Sixty-nine patients with endoscopically proven colorectal cancer underwent CE-CTC, after incomplete conventional colonoscopy. Two experienced radiologists evaluated site, length, and TNM staging of colorectal cancers on three-dimensional double contrast enema-like views, 2D axial and multiplanar reconstructions. All the patients underwent colorectal resection and surgery bulletin, pathology of surgical specimens, and radiological follow-up at about 8 months were used as reference standard.

Results

The detection rate of colorectal cancer was 100 % (75/75); CE-CTC allowed for a diagnosis of a synchronous colorectal cancer in five patients (7 %). CE-CTC correctly judged the site of the lesions in all the cases; clinically significant localization errors at conventional colonoscopy were noted in 3 out of 69 patients (4 %). Additional colonic polyps greater than 6 mm in diameter were found in 21 out of 69 patients (30 %); in two patients (3 %) the surgeon performed an enlarged colectomy to include synchronous polyps proximal to colorectal cancer. Sensitivity, specificity, PPV, NPV, and accuracy were for T1–T2 vs. T3–T4: 96 %, 71 %, 92 %, 87 %, and 91 %, respectively; for N: 94 %, 42 %, 64 %, 86 %, and 70 %; for M: 100 %, 100 %, 83 %, 100 %, and 97 %. There were no complications associated with CE-CTC.

Conclusion

Information given by CE-CTC concerning colorectal cancer location and synchronous colonic cancers and polyps changed the laparoscopic surgical strategy in almost 14 % of patients.  相似文献   
66.
The possibility of detecting unknown internal carotid artery stenoses in patients undergoing biphasic multidetector computed tomography (MDCT) for current or previous head and neck cancer was investigated in 52 patients who underwent four-row MDCT (4 mm×1.25 mm collimation, pitch 3, kVp 120, mAs 140; 90–100 ml of non-ionic contrast agent at 2 ml/s, early and late phases). Vessel stenoses were classed as severe (70–99%), moderate (30–69%), or mild (<30%). Internal carotid arteries (ICAs) with vessel stenosis was found in 37 patients (age 67.0±9.8 years, median 69 years) and 67 ICAs. Four patients (age 65.5±9.7 years) had severe stenosis, all of them associated with contralateral moderate stenosis. Seventeen patients (age 70.35±9.78 years) had moderate stenosis, bilateral (n=7), associated with contralateral mild stenosis (n=8), unilateral (n=2). Sixteen patients (age 64.8±9.8 years) had mild stenosis, bilateral (n=10) or unilateral (n=6). Of the four patients with unknown MDCT-detected severe stenosis, three had a change of therapy: one endarterectomy before tumor surgery, one combined vascular and tumor surgery, and one patient with a previously treated hypopharyngeal cancer had carotid stenting. In conclusion, of 52 patients, four (7.7 %) had unknown severe ICA stenoses, three of them with relevant impact on therapy. ICAs should be carefully evaluated for atherosclerotic disease using biphasic MDCT for head and neck cancer.  相似文献   
67.

Background

Infantile spasms represent a serious epileptic syndrome that occurs in the early infantile age. ACTH and Vigabatrin are actively investigated drugs in its treatment. This study describes the comparison of their efficacy in a large series of patients with infantile spasms from Pakistan.

Methods

All patients with infantile spasms who presented to Aga Khan University Hospital, Karachi, Pakistan from January, 2006 to April, 2008 were included in this study. Inclusion criteria were clinical symptoms of infantile spasms, hypsarrythmia or modified hyparrythmia on electroencephalography, at least six months of follow-up period and receipt of any of the two drugs mentioned above. The type of drug distribution was random according to the availability, cost and ease of administration.

Results

Fifty six cases fulfilled the inclusion criteria. 62.5% were males. Mean age at onset of seizures was 5 ± 1.4 months. Fifty two (92.8%) patients demonstrated hypsarrythmia on electroencephalography. 64.3% cases were identified as symptomatic while 19.6% were cryptogenic and 16.1% were idiopathic. Eighteen patients received ACTH while 38 patients received Vigabatrin as first line therapy. Initial response to first line therapy was similar (50% for ACTH and 55.3% for Vigabatrin). Overall, the symptomatic and idiopathic groups responded better to Vigabatrin. The relapse rate was higher for ACTH as compared to Vigabatrin (55.5% vs. 33.3%) when considering the first line therapy. Four patients evolved to Lennox-Gastaut variant; all of these patients had initially received Vigabatrin and then ACTH.

Conclusion

Vigabatrin and ACTH showed no significant difference in the initial treatment of infantile spasms. However, patients receiving ACTH were 1.2 times more likely to relapse as compared to the patients receiving Vigabatrin when considering monotherapy. We suggest that Vigabatrin should be the initial drug of choice in patients presenting with infantile spasms. However, larger studies from developing countries are required to validate the therapeutic trends observed in this study.  相似文献   
68.
Neuroticism involves a tendency for enhanced emotional and cognitive processing of negative affective stimuli and a propensity to worry and be anxious. It is known that this trait modulates fear learning and the activation of brain regions involved in it such as the amygdala, hippocampus, and prefrontal cortex and their connectivity. Thirty-nine (21 female) 14-year-old healthy adolescents participated in functional magnetic resonance imaging (fMRI) of aversive pavlovian differential delay conditioning. An unpleasant sound served as unconditioned stimulus (US) and pictures of neutral male faces as conditioned stimuli (CS+ followed by the US in 50% of the cases; CS− never followed by the US). During acquisition (CS+/− differentiation), higher levels of neuroticism were associated with a stronger interaction between the right amygdala and the right hippocampus as well as the right amygdala and prefrontal cortical regions, specifically ventromedial prefrontal cortex, dorsolateral prefrontal cortex, and anterior cingulate cortex. The association of stronger conditionability of fear and connectivity of brain regions related to consolidation of fear associations and neuroticism points to underlying mechanisms of the enhanced propensity for anxiety disorders in highly neurotic participants. This is especially important in adolescence, a vulnerable time for the onset of mental disorders such as anxiety disorders.  相似文献   
69.
Genetic variation in a genomic region on chromosome 15q25.1, which encodes the alpha5, alpha3, and beta4 subunits of the cholinergic nicotinic receptor genes, confers risk to smoking and nicotine dependence (ND). Neural reward-related responses have previously been identified as important factors in the development of drug dependence involving ND. Applying an imaging genetics approach in two cohorts (N=487; N=478) of healthy non-smoking adolescents, we aimed to elucidate the impact of genome-wide significant smoking-associated variants in the CHRNA5–CHRNA3–CHRNB4 gene cluster on reward-related neural responses in central regions such as the striatum, orbitofrontal and anterior cingulate cortex (ACC), and personality traits related to addiction. In both samples, carriers of the rs578776 GG compared with AG/AA genotype showed a significantly lower neural response to reward outcomes in the right ventral and dorsal ACC but not the striatum or the orbitofrontal cortex. Rs578776 was unrelated to neural reward anticipation or reward magnitude. Significantly higher scores of anxiety sensitivity in GG compared with AG/AA carriers were found only in sample 1. Associations with other personality traits were not observed. Our findings suggest that the rs578776 risk variant influences susceptibility to ND by dampening the response of the ACC to reward feedback, without recruiting the striatum or orbitofrontal cortex during feedback or anticipation. Thus, it seems to have a major role in the processing of and behavioral adaptation to changing reward outcomes.  相似文献   
70.

OBJECTIVE:

to verify associations between overweight and the characteristics of young adult students to support nursing care.

METHOD:

case-control study conducted with young adults from public schools. The sample was composed of 441 participants (147 cases and 294 controls, with and without excess weight, respectively). Sociodemographic and clinical characteristics were collected together with exposure factors and anthropometrics. Multiple logistic regression was used. The study received Institutional Review Board approval.

RESULTS:

statistically significant association with overweight: non-Caucasian, having a partner; weight gain during adolescence, mother''s excess weight, the use of obesogenic medication, augmented diastolic blood pressure, of abdominal circumference and waist/hip ratio. In addition to these, schooling and weight gain during childhood were also included in the multivariate analysis. After adjustment, the final model included: having a partner, weight gain during adolescence, augmented diastolic blood pressure and abdominal circumference.

CONCLUSION:

the analysis of predictor variables for excess weight among young adult students supports nurses in planning and developing educational practices aimed to prevent this clinical condition, which is a risk factor for other chronic comorbidities, such as cardiovascular diseases.  相似文献   
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