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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   
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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   
4.
Diagnosis of gastric carcinoma by classification on feature projections   总被引:1,自引:0,他引:1  
A new classification algorithm, called benefit maximizing classifier on feature projections (BCFP), is developed and applied to the problem of diagnosis of gastric carcinoma. The domain contains records of patients with known diagnosis through gastroscopy results. Given a training set of such records, the BCFP classifier learns how to differentiate a new case in the domain. BCFP represents a concept in the form of feature projections on each feature dimension separately. Classification in the BCFP algorithm is based on a voting among the individual predictions made on each feature. In the gastric carcinoma domain, a lesion can be an indicator of one of nine different levels of gastric carcinoma, from early to late stages. The benefit of correct classification of early levels is much more than that of late cases. Also, the costs of wrong classifications are not symmetric. In the training phase, the BCFP algorithm learns classification rules that maximize the benefit of classification. In the querying phase, using these rules, the BCFP algorithm tries to make a prediction maximizing the benefit. A genetic algorithm is applied to select the relevant features. The performance of the BCFP algorithm is evaluated in terms of accuracy and running time. The rules induced are verified by experts of the domain.  相似文献   
5.
FANCG was the third Faconi anaemia gene identified and proved to be identical to the previously cloned XRCC9 gene. We present the pathogenic mutations and sequence variants we have so far identified in a panel of FA-G patients. Mutation screening was performed by PCR, single strand conformational polymorphism analysis and protein truncation tests. Altogether 18 mutations have been determined in 20 families - 97% of all expected mutant alleles. All mutation types have been found, with the exception of large deletions, the large majority is predicted to lead to shortened proteins. One stop codon mutation, E105X, has been found in several German patients and this founder mutation accounts for 44% of the mutant FANCG alleles in German FA-G patients. Comparison of clinical phenotypes shows that patients homozygous for this mutation have an earlier onset of the haematological disorder than most other FA-G patients. The mouse Fancg sequence was established in order to evaluate missense mutations. A putative missense mutation, L71P, in a possible leucine zipper motif may affect FANCG binding of FANCA and seems to be associated with a milder clinical phenotype.  相似文献   
6.
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   
7.
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   
8.
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   
9.
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   
10.
Using plasma amyloid beta protein (Abeta42) levels as an intermediate, quantitative phenotype for late onset Alzheimer's disease (LOAD), we previously obtained significant linkage at approximately 80 cM on chromosome 10. Linkage to the same region was obtained independently in a study of affected LOAD sib-pairs. Together, these two studies provide strong evidence for a novel LOAD locus on chromosome 10 that acts to increase Abeta42. VR22 is a large (1.7 Mb) gene located at 80 cM that encodes alpha-T catenin, which is a binding partner of beta catenin. This makes VR22 an attractive candidate gene because beta catenin interacts with presenilin 1, which has many mutations that elevate Abeta42 and cause early onset familial AD. We identified two intronic VR22 SNPs (4360 and 4783) in strong linkage disequilibrium (LD) that showed highly significant association (P=0.0001 and 0.0006) with plasma Abeta42 in 10 extended LOAD families. This association clearly contributed to the linkage at approximately 80 cM because the lod scores decreased when linkage analysis was performed conditional upon the VR22 association. This association replicated in another independent set of 12 LOAD families (P=0.04 for 4783 and P=0.08 for 4360). Bounding of the association region using multiple SNPs showed VR22 to be the only confirmed gene within the region of association. These findings indicate that VR22 has variant(s) which influence Abeta42 and contribute to the previously reported linkage for plasma Abeta42 in LOAD families.  相似文献   
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