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991.
An electromyographic study was undertaken to discover the mechanism by which the Myo-monitor instrument causes muscle contraction. Our data, which strongly suggest that the distal axons of the motoneurons are directly stimulated, lend support to previous studies showing that the stimulus does not cause reflex activation of the jaw closing muscles. Inasmuch as the stimulus acts only in the periphery without the participation of the central nervous system, the ability of the instrument to produce a reflexly controlled occlusal position is highly questionable. Furthermore, we believe that there is no evidence that reflex jaw closure could ever be used to establish a physiologic occlusal position.  相似文献   
992.
993.
OBJECTIVES: To compare the quality of conventional complete dentures fabricated with two different techniques. A randomized controlled clinical trial was conducted to compare traditional (T) and simplified (S) methods of making complete conventional dentures on patients' ratings of satisfaction, comfort and function at 3 and 6 months following delivery. The quality of the prostheses was rated by prosthodontists at 6 months. MATERIALS AND METHODS: One hundred twenty-two male and female edentulous individuals, aged 45-75 years, were randomly allocated into groups that received dentures made with either T or S methods. Following delivery, patients' ratings of several denture-related factors were measured using 100mm visual analogue scales, and denture quality was assessed by blinded prosthodontists using ratings on a validated quantitative scale. RESULTS: There were no significant differences between the two groups in patient ratings for overall satisfaction (3 months: mean T = 83 mm, mean S = 83 mm, P = 0.97; 6 months: mean T = 79 mm, mean S = 79 mm, P = 0.96) or in prosthodontists' ratings of denture quality (T = 66, S = 63; P = 0.38). CONCLUSION: These results show that the quality of complete dentures does not suffer when manufacturing techniques are simplified to save time and materials. Dental educators should consider these findings when re-designing prosthodontic training programs.  相似文献   
994.
995.
The complex of myxomas, spotty pigmentation, and endocrine overactivity is a recently recognized syndrome, transmitted as an autosomal dominant trait. The most serious component of the disorder is cardiac myxoma, which has caused the death of one fourth of the affected patients and serious disability in an equal number. It is, therefore, important to recognize patients at risk from the syndrome and, in particular, to test them for cardiac myxoma. Fortunately, in many patients the myxoma complex has a clearly visible marker: mucocutaneous pigmentation. Among 58 patients with the syndrome, spotty facial pigmentation was present in 36 (62%), and 29 (50%) of these also had pigmented spots on their lips. This type and distribution of pigmentation should be a clue to the possible presence of the complex of myxomas, spotty pigmentation, and endocrine overactivity, and patients thus affected should be referred for further investigation. Oral cavity myxoma(s) occurred in four patients with the syndrome.  相似文献   
996.
PURPOSE: The aim of this randomized clinical trial was to compare the relative efficacy of mandibular overdentures retained by only two implants and a bar attachment with conventional dentures. MATERIALS AND METHODS: Edentulous adults, aged 35 to 65 years, were randomly assigned to two groups that received either a mandibular conventional denture (n = 48) or an overdenture supported by two endosseous implants with a connecting bar (n = 54). All subjects rated their general satisfaction and other features of their original dentures and their new prostheses (comfort, stability, ability to chew, speech, esthetics, and cleaning ability) on 100-mm visual analogue scales prior to treatment and 2 months postdelivery. Oral health-related quality of life was also evaluated pre- and posttreatment. RESULTS: Multiple regression analysis revealed that the mean general satisfaction was significantly higher in the overdenture group than in the conventional denture group (P = .0001). Age, gender, marital status, and income were not significantly associated with ratings of general satisfaction. Furthermore, the implant group gave significantly higher ratings on three additional measures of the prostheses (comfort, stability, and ease of chewing; P < .05). CONCLUSION: A mandibular two-implant overdenture opposed by a maxillary conventional denture is a more satisfactory treatment than conventional dentures for edentulous middle-aged adults.  相似文献   
997.
Lund AD  Palacios SD 《The Laryngoscope》2011,121(12):2658-2660
This case report describes carotid-cochlear dehiscence, a rare and possibly fatal condition if missed or ignored on initial work-up of several otologic procedures. Thinning of the bony plate separating the carotid canal from other anatomic structures can occur anywhere along the course of the canal, including the carotid-cochlear bony plate. This condition should be recognized by all otolaryngologists in that it can mimic other otologic pathologies. The aim of this report was to call attention to this condition and its associated mimicking symptoms and inform on its proper management. The idea for this review was formed from the case of a patient who presented with pulsatile tinnitus and was found to have carotid-cochlear dehiscence. Carotid-cochlear dehiscence is a rare anatomic variation of which the neurotologic surgeon should be aware. This condition can mimic common otolaryngologic pathologies that regularly present themselves in clinical settings. We present what we believe to be the fourth reported case of carotid-cochlear dehiscence in the literature. The patient presented having only the complaint of pulsatile tinnitus and was later diagnosed with this rare condition. We advocate a thorough preoperative work-up, including high-resolution computed tomography and careful operative planning in a case-specific manner. This is especially important when common pathologies do not become apparent after careful investigation.  相似文献   
998.
999.
In this study we have used in situ hybridization with radiolabeled antisense RNA probes to examine the expression of mRNA for urokinase-type plasminogen activator and its receptor in histologic samples of squamous cell (n = 7) and basal cell (n = 7) carcinomas of the skin. Messenger RNA for both urokinase-type plasminogen activator and its receptor were expressed in all of the squamous cell carcinomas, but could not be detected in the basal cell carcinomas. In all of the seven squamous cell carcinomas a signal for urokinase-type plasminogen activator receptor mRNA was detected focally in well-differentiated cancer cells surrounding keratinized pearls, and in four specimens urokinase-type plasminogen activator receptor mRNA was in addition expressed by cancer cells at the edge of invasively growing strands of tumor. Urokinase-type plasminogen activator mRNA expression was found in virtually all the cancer cells of the squamous cell carcinomas, and importantly we found, by hybridizations for urokinase-type plasminogen activator and its receptor mRNA on adjacent sections of squamous cell carcinomas, that it was exactly the invading cancer cells that simultaneously expressed both these components required for plasmin-mediated proteolysis at the cell surface. We have previously shown that both urokinase-type plasminogen activator and its receptor mRNA are expressed by the leading-edge keratinocytes in regenerating epidermis during mouse skin wound healing, and that wound healing is impaired in mice made deficient in plasminogen by targeted gene disruption. We propose that there are similarities between the mechanisms of generation and regulation of extracellular proteolysis during skin re-epithelialization and squamous cell carcinoma invasion. The ability of the squamous carcinoma cells to mimic the "invasive" phenotype of re-epithelializing keratinocytes may be one of the factors that make squamous cell carcinomas more aggressive tumors than basal cell carcinomas.  相似文献   
1000.
Aim: To study the prevalence and characteristics of psychiatric symptoms and disorders in young adults born with low birth weight. Methods: At 20 years of age 44 very low birth weight (VLBW: birth weight ≤1500 g), 55 term born small for gestational age (SGA: birth weight <10th percentile) and 75 control subjects born 1986–1988 were assessed using the interview Schedule for Affective Disorders and Schizophrenia for School‐age children and Structured Clinical Interview for DSM‐IV Personality Disorders, Children’s Global Assessment Scale and Attention deficit hyperactivity disorder (ADHD) Rating Scale IV; self‐report and parent report. Results: Fourteen (33%) VLBW versus six (8%) control participants had a definite psychiatric disorder: OR = 5.6 (1.9–15.9). In the term SGA group, 14 (26%) had a disorder: OR = 3.9 (1.4–11.0) vs controls. Anxiety disorders and ADHD were the most frequent diagnoses. The differences were not explained by gender, assessment age or parental socioeconomic status. ADHD Rating Scale mean scores were higher in parent reports in the VLBW group and in self‐reports in the term SGA group compared with the control group. Conclusion: Children born with low birth weight whether caused by preterm birth or by growth retardation at term seem to be at increased risk for psychiatric disorders as young adults.  相似文献   
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