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1.
Abstract –  In the treatment of crown fractures, adhesive fragment reattachment provides a good alternative to other restorative techniques, offering several advantages. The present paper reports a case in which the treatment of a cervical crown fracture was accomplished by reattaching the tooth fragment with a flowable resin composite. Orthodontic root extrusion was performed with a modified Hawley appliance prior to fragment reattachment. The clinical and radiographic results after 2.5 years were successful.  相似文献   
2.
Speech-associated attitudes of stuttering and nonstuttering children   总被引:1,自引:0,他引:1  
A Dutch version of the Communication Attitude Test (Brutten, 1985) was used to assess the speech-associated attitudes of 70 stuttering and 271 nonstuttering Belgian children of elementary and middle school age. The results showed that the stuttering children evidenced significantly more negative attitudes toward speech than did their nonstuttering peers. This difference was present from age 7, the youngest age group studied, on up. Moreover, a significant group x age interaction revealed that the speech-related attitudes of the stuttering children became more negative with increasing age. In contrast, those of the nonstuttering children became less negative after age 9. These findings suggest that, in the course of fluency therapy for youngsters who stutter, negative attitudes toward speech should be addressed. This is especially true if, as with adults who stutter, negative attitudes are predictive of therapeutic failure.  相似文献   
3.
Plasma amyloid beta protein (Abeta42) levels and late onset Alzheimer's disease (LOAD) have been linked to the same region on chromosome 10q. The PLAU gene within this region encodes urokinase-type plasminogen activator, which converts plasminogen to plasmin. Abeta aggregates induce PLAU expression thereby increasing plasmin, which degrades both aggregated and non-aggregated forms of Abeta. We evaluated single nucleotide polymorphisms (SNPs) in PLAU for association with Abeta42 and LOAD. PLAU SNP compound genotypes composed of haplotype pairs showed significant association with AD in three independent case-control series. PLAU SNP haplotypes associated significantly with plasma Abeta42 in 10 extended LOAD families. One of the SNPs analyzed was a missense C/T polymorphism in exon 6 of PLAU (PLAU_1=rs2227564), which causes a proline to leucine change (P141L). We analyzed PLAU_1 for association with AD in six case-control series and 24 extended LOAD families. The CT and TT PLAU_1 genotypes showed association (P=0.05) with an overall estimated odds ratio of 1.2 (1.0-1.5). The CT and TT genotypes of PLAU_1 were also associated with significant age-dependent elevation of plasma Abeta42 in 24 extended LOAD families (P=0.0006). In knockout mice lacking the PLAU gene, plasma--but not brain--Abeta42 as well as Abeta40 was significantly elevated, also in an age-dependent manner. The PLAU_1 associations were independent of the associations we found among plasma Abeta42, LOAD and variants in the IDE or VR22 region. These results provide strong evidence that PLAU or a nearby gene is involved in the development of LOAD. PLAU_1 is a plausible pathogenic mutation that could act by increasing Abeta42, but additional biological experiments are required to show this definitively.  相似文献   
4.
Risk for late onset Alzheimer disease (LOAD) and plasma amyloid beta levels (Abeta42; encoded by APP), an intermediate phenotype for LOAD, show linkage to chromosome 10q. Several strong candidate genes (VR22, PLAU, IDE) lie within the 1-lod support interval for linkage. Others have independently identified haplotypes in the chromosome 10q region harboring IDE that show highly significant association with intermediate AD phenotypes and with risk for AD. To pursue these associations, we analyzed the same haplotypes for association with plasma Abeta42 in 24 extended LOAD families and for association with LOAD in two independent case-control series. One series (MCR, 188 age-matched case-control pairs) did not show association (p=0.64) with the six haplotypes in the 276-kb region spanning three genes (IDE, KNSL1, and HHEX) previously shown to associate with LOAD. The other series (MCJ, 109 age-matched case-control pairs) showed significant (p=0.003) association with these haplotypes. In the MCJ series, the H4 (odds ratio [OR]=5.1, p=0.003) and H2(H7) haplotypes (OR=0.60, p=0.04) had the same effects previously reported. In this series, the H8 haplotype (OR=2.7, p=0.098) also had an effect similar as in one previous case control series but not in others. In the extended families, the H8 haplotype was associated with significantly elevated plasma Abeta42 (p=0.02). In addition, the H5(H10) haplotype, which is associated with reduced risk for AD in the other study is associated with reduced plasma Abeta42 (p=0.007) in our family series. These results provide strong evidence for pathogenic variant(s) in the 276-kb region harboring IDE that influence intermediate AD phenotypes and risk for AD.  相似文献   
5.
Perforation of the uterus by an intrauterine device (IUD) is a serious complication occurring at or following 1/350 to 1/2,500 insertions. It is more common among women with 'lost' IUDs. If a woman presents with pelvic pain and a history of a 'lost' IUD, X-rays of the abdomen and of the pelvis should be ordered. We report on a 'lost' IUD that had been inserted 12 years previously. It was found in the lower anterior abdominal wall. Most probably uterine perforation had happened during a dilatation and curettage (D & C) attempted for removal of the device. Thereafter the IUD must have migrated to the abdominal wall. This case illustrates that unless it can be recovered by simple traction on the threads, a trained medical professional should be called upon for removal of the IUD.  相似文献   
6.
Puffing patterns (number of puffs, puff volume, puff duration, puff interval, peak pressure, peak flow, peak latency), respiratory smoke inhalation (postpuff inspiratory latency, volume and time and postpuff expiratory volume and time), and the pre- to postsmoking boost of tidal air CO concentration were analyzed in 117 regular smokers. They smoked both a cigarette of the habitual brand and a second cigarette of a brand with about 40 to 50% lower machine standard smoke yields and the most similar taste quality. The pre- to postsmoking CO boost remained unrelated to the smoke deliveries of the cigarettes in both comparisons (interindividual and switching). Estimated mouth intake of nicotine was strongly dependent on the smoke yield variables of the cigarettes but remained uncorrelated with CO absorption. The discrepancy between mouth smoke intake and alveolar smoke absorption could not be explained by the volumes or durations of the postpuff respiratory cycle. Multiple regression analyses suggested differential modes of control for the daily number of cigarettes smoked, for the patterns of puffing, for respiratory inhalation, and finally for alveolar CO absorption. The results are discussed in relation to the dynamics of puffing and inhalation and their possible relevance for tobacco-related diseases.  相似文献   
7.
Nitric oxide (NO) plays an important role in the regulation of upper respiratory function. Patients with untreated allergic rhinitis (AR) have an increased level of NO in the nasal cavity compared to normal individuals. We aimed to investigate serum levels of arginase and NO metabolites nitrite/nitrate in patients with AR during the symptomatic period. The patient and control groups consisted of 14 males and 12 females (mean age: 29, range: 20-40 years), and 10 males and 10 females (mean age: 27, range: 22-38 years), respectively. Nitrite/nitrate levels were 0.98 +/- 0.33 ng/ml in the patients with AR, and 0.78 +/- 0.26 ng/ml in the control group (p = 0.03). Arginase levels were 28.8 +/- 14.1 ng/ml in the patients with AR, and 20.8 +/- 13.5 ng/ml in the control group. The difference between the groups was statistically insignificant (p = 0.24). Our results support the view that NO plays an important role in the pathogenesis of AR, and NO metabolites may be used as a marker for monitoring the disease activity and therapy.  相似文献   
8.
Over the last decade positron emission tomography (PET) has been used extensively for the study of language and other cognitive and sensorimotor processes in healthy and diseased individuals. In the present study, [15O]H2O PET scanning was used to investigate the lateralization and functional distribution of cortical and subcortical activity involved in single word reading in stuttering and nonstuttering individuals. Ten right-handed male stuttering adults and matched nonstuttering individuals were instructed to read individually presented single words either silently or out loud. Subtraction of functional brain images obtained during each of the two reading tasks, and during a non-linguistic baseline task, was used to calculate within-group and between-group differences in regional cerebral blood flow by means of statistical parametric mapping. Increased activation in the left anterior cingulate cortex (ACC) was observed during silent reading in the stuttering speakers but not in the nonstuttering group. Because of the hypothesized role of the ACC in selective attention and covert articulatory practice, it is suggested that the observed increased ACC activation in the stuttering individuals reflects the presence of cognitive anticipatory reactions related to stuttering. During the oral reading task, within-group comparisons showed bilateral cortical and subcortical activation in both the stuttering and the nonstuttering speakers. Between-group comparisons showed a proportionally greater left hemisphere activation in the nonstuttering speakers, and a proportionally greater right hemisphere activation in the stuttering individuals. The results of the present study provide qualified support for the hypothesis that stuttering adults show atypical lateralization of language processes.  相似文献   
9.
Conditional cash transfer (CCT) and cognitive-behavioral treatments are evidence-based approaches to reduce stimulant use and sexual risk taking. We describe the adaptation and implementation of sequential behavioral interventions for Cambodian female entertainment and sex workers (FESW) who use amphetamine-type stimulants (ATS): (1) a 12-week CCT intervention; and (2) a 4-week cognitive-behavioral aftercare (AC) group. An ongoing cluster randomized stepped wedge trial in 10 Cambodian provinces is enrolling FESW with confirmed recent ATS use to examine the effectiveness of CCT + AC. In the first six provinces, 138 of the 183 eligible FESW (75 %) enrolled in CCT and completed a median of 25 (interquartile range 9–32) of the 36 urine screening visits. Of the 84 participants who were eligible for AC, 79 completed at least one session (94 %) and 57 completed three or more sessions (68 %). Culturally tailored behavioral interventions to reduce ATS use and optimize HIV prevention are feasible in resource-limited settings.  相似文献   
10.
Purpose

Hypophysitis is a heterogeneous condition that includes inflammation of the pituitary gland and infundibulum, and it can cause symptoms related to mass effects and hormonal deficiencies. We aimed to evaluate the potential role of machine learning methods in differentiating hypophysitis from non-functioning pituitary adenomas.

Methods

The radiomic parameters obtained from T1A-C images were used. Among the radiomic parameters, parameters capable of distinguishing between hypophysitis and non-functioning pituitary adenomas were selected. In order to avoid the effects of confounding factors and to improve the performance of the classifiers, parameters with high correlation with each other were eliminated. Machine learning algorithms were performed with the combination of gray-level run-length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray-level co-occurrence entropy.

Results

A total of 34 patients were included, 17 of whom had hypophysitis and 17 had non-functioning pituitary adenomas. Among the 38 radiomics parameters obtained from post-contrast T1-weighted images, 10 tissue features that could differentiate the lesions were selected. Machine learning algorithms were performed using three selected parameters; gray level run length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray level co-occurrence entropy. Error matrices were calculated by using the machine learning algorithm and it was seen that support vector machines showed the best performance in distinguishing the two lesion types.

Conclusions

Our analysis reported that support vector machines showed the best performance in distinguishing hypophysitis from non-functioning pituitary adenomas, emphasizing the importance of machine learning in differentiating the two lesions.

  相似文献   
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