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21.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
22.
Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented.  相似文献   
23.
Certain parental cognitions about child sleep and bedtime behaviours used with their child have been linked to poorer child sleep. However, previous research has focused on mothers and explored only a limited range of sleep-related cognitions and practices. The present study investigated whether parental cognitions and sleep-related practices (both in connection with their own sleep and their child's sleep), alongside the bedtime behaviours used with their child were associated with and/or were predictive of their child's sleep. Mothers and fathers from 44 families (with a child aged 12–24 months) separately completed questionnaires reporting (i) their cognitions (about their own sleep and their child's sleep), (ii) sleep-related practices (used in connection with their own and their child's sleep) and (iii) bedtime behaviours used with their child. Child sleep was assessed through parental report and actigraphy. Both parents’ cognitions about their own sleep predicted cognitions about their child's sleep. Mothers’ own sleep-related practices predicted the types of practices they used with their child. Different patterns of maternal and paternal variables influenced parental perceptions of their child having a sleep problem. The present findings highlight the importance of including mothers and fathers in child sleep research. Parents’ dysfunctional cognitions (their own sleep) and broader sleep-related practices (their own and child sleep) should be considered when exploring influences on child sleep. Results have possible implications for targets of interventions for child sleep problems and also potential implications for theoretical models of child sleep.  相似文献   
24.

Objective

Infancy is both a critical window for hypothalamic–pituitary–adrenal (HPA) axis development, and a sensitive period for social–emotional influences. We hypothesized that the social–emotional quality of maternal–infant interactions are associated with methylation of HPA-axis gene NR3C1 later in childhood.

Methods

Using a subsample of 114 mother-infant pairs from the Avon Longitudinal Study of Parents and Children (ALSPAC), linear regression models were created to predict variance in methylation of seven selected CpG sites from NR3C1 in whole blood at age 7 years, including the main predictor variable of the first principal component score of observed maternal–infant interaction quality (derived from the Thorpe Interaction Measure at 12 months of age) and covariates of cell-type proportion, maternal financial difficulties and marital status at 8 months postnatal, child birthweight, and sex.

Results

CpG site cg27122725 methylation was negatively associated with warmer, more positive maternal interaction with her infant (β = 0.19, p = .02, q = 0.13). In sensitivity analyses, the second highest quartile of maternal behavior (neutral, hesitant behavior) was positively associated with cg12466613 methylation. The other five CpG sites were not significantly associated with maternal–infant interaction quality.

Conclusions

Narrow individual variation of maternal interaction with her infant is associated with childhood methylation of two CpG sites on NR3C1 that may be particularly sensitive to environmental influences. Infancy may be a sensitive period for even small influences from the social–emotional environment on the epigenetic determinants of HPA-axis function.  相似文献   
25.
26.
Our aim was to characterize epithelial cell proliferative activity within the oral cavity and to find out if there were differences between sites with high and low incidence of cancer. A total of 105 samples of clinically normal mucosa were harvested from various intra-oral sites. Excised specimens were incubated in vitro with tritiated thymidine and bromodeoxyuridine to 'double label' cells undergoing DNA synthesis, and enable calculation of the duration of S phase and estimation of variables of cell flux to and from S. Mean labelling indices (percentage of cells within the S phase of the cell cycle) were highest in the floor of mouth (12.3%) and ventral tongue (10.1%), while activity was lowest in the dorsum of tongue (4.3%) and the palate (7.2%), P<0.001. In general, both cell influx and the duration of S increased proportionally to the labelling index. Sites with a high incidence of cancer were characterized by high labelling indices, increased cell influx and a prolonged S phase.  相似文献   
27.
The psychological health and job satisfaction of 285 GPs and 89 medical house officers from Leeds was compared using standardized self-report measures. Forty-eight per cent of the GPs and 20% of the house officers scored as 'cases' of psychiatric disorder. The GPs were less satisfied with the recognition they received for their work and their hours of work, but more satisfied with their job variety and job autonomy. Further research examining the sources of work-related distress in different medical settings could help inform future organizational changes.  相似文献   
28.
29.
The Dunning H rat prostate tumor (R3327H) is a widely used experimental model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been characterized as androgen-sensitive, androgen-receptor (AR) positive, prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To date, the tumor has been maintained by serial passage in vivo because of the lack of an in vitro cell line that retains the characteristics of the in vivo tumor. The objective of the present study was to establish a propagable cell line from R3327H adenocarcinoma that maintained androgen sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in vivo R3327H tumor was dissociated with collagenase and placed into Richter's improved media (with supplements). A cytokeratin-positive epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line (HUNC-S) were generated from the primary culture, subcultured continuously for >300 days, and passaged >50 times. Survival of the HUNC-E cell line in vitro depended on several media supplements, including nicotinamide, insulin, transferrin, selenium and epidermal growth factor (EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the culture period, as confirmed by immunocytochemistry and Western blot analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT) to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent growth and PSA production, which demonstrated the androgen-sensitive nature of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1 ratio and introduced subcutaneously into syngeneic male hosts, tumors formed in 2/3 animals with an average latency of 7 months. RT-PCR and immunocytochemical characterization of the HUNC cell lines revealed that the cells expressed several growth factors and their cognate receptors, including HGF, TGF-alpha and the TGF-betas, indicating the establishment of potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S CaP cell lines, which retain the characteristics of the epithelial and stromal components of the in vivo R3327H tumor, will allow a more thorough and informative molecular and biological analysis of prostatic adenocarcinoma.   相似文献   
30.
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