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831.
832.
Osteopenia is common in preterm babies, but its pathogenesis is uncertain. In this study bone density in babies was quantitated, postnatal bone mineralization compared to expected intrauterine bone mineralization and the pathogenesis of osteopenia investigated. Healthy babies (103 term, 76 preterm) were examined clinically, biochemically and radiologically the day after birth and at a time corresponding to expected full term gestation. Appendicular bone density was quantitated by magnification radiogrammetry, using the humeral cortical index (CI). The CI of preterm and term babies was similar the day after birth. In preterm babies elevated serum alkaline phosphatase and high urinary hydroxyproline indicated increased bone turnover. The CI of preterm babies at expected full term gestation was lower (p = 0.0001) than that of term babies at birth, implying that postnatal bone mineralization lagged behind expected intrauterine bone mineralization. Radiologic data suggested increased endosteal resorption rather than decreased bone formation. At expected full term gestation the preterm babies had higher serum alkaline phosphatase and urinary calcium, phosphate, c-AMP and hydroxyproline (p = 0.0001) than term babies at birth, and 15% had periosteal reactions. The biochemical as well as the radiologic data therefore indicated high turnover osteopenia in preterm babies. We conclude that postnatal bone mineralization in preterm babies lagged significantly behind expected intrauterine bone mineralization and that the osteopenia observed in preterm babies is caused by increased bone resorption and not by decreased bone formation. The cause(s) of this high turnover osteopenia, however, remains to be ascertained.  相似文献   
833.
Factors influencing natural history and clinical course of pain in temporomandibular disorders (TMD) are largely unknown. Physical, psychological and behavioral data from a population-based epidemiologic study of TMD were examined in 234 cases of persons reporting TMD pain. The cases were assigned to one of five pain pattern groups based on changes in average TMD pain from baseline to 5-year follow-up: (i) remitted (49% of the sample), (ii) high-improvement (14%), (iii) low-improvement (9%), (iv) same (13%), and (v) worse (16%). For each pain change group, an ANOVA-derived pattern analysis was performed to assess whether the pattern of change in each of seven physical and three psychological variables was congruent or dissimilar to the pattern of change in average pain intensity. For none of the physical or psychological variables was the change over time completely congruent with the changes in pain. Changes in ambient average TMD pain were most closely related to those clinical variables whose assessment is influenced by pain or other self-reported symptoms (e.g., number of muscle sites painful to examiner palpation), while the amount of pain change was less closely related to changes in clinical variables, such as joint sounds, where assessment is not dependent on subjective report. The three psychological variables, anxiety, depression, and somatization, displayed similar change patterns, but these patterns were distinctly different from those of the physical variables in that the remitted pain group was at the population mean at baseline for these psychological variables and remained there; significant improvement in psychological status was observed only in the pain group showing high improvement. The other three pain change groups exhibited elevated psychological distress scores at both baseline and 5 years. These results indicate that although the relationships among the course of pain, of physical variables, and of psychological variables are complicated, the 5-year outcome in pain is largely independent of readily discernible changes in clinical signs.  相似文献   
834.
It is important that all members of the dental office staff be trained to promptly recognize and efficiently manage emergency situations. This paper discusses how to prepare a dental office and staff for emergencies. It also describes several emergencies that may occur in dental offices and discusses methods of handling them.  相似文献   
835.
A Monk  SF Pushkin  AL Nelson  JE Gunning 《Canadian Metallurgical Quarterly》1996,174(6):1695-9; discussion 1699-700
OBJECTIVE: Our purpose was to study the feasibility of conservatively managing selected cases of dysplasia involving endocervical cone margins. STUDY DESIGN: A retrospective review of patients conservatively managed after being found to have squamous cell dysplasia involving the endocervical margins of their cervical cone biopsy specimens. In phase I patients who had cold-knife conization with positive endocervical margins underwent repeat Papanicolaou smears and colposcopy, with biopsies and endocervical curettage as indicated. Those found free of disease were followed up with frequent Papanicolaou smears. In phase II patients with dysplasia to the endocervical resection edges on loop electrical excision procedure biopsy specimens were followed up with frequent cytologic studies. RESULTS: In phase I, 31 patients with positive endocervical margins on cold-knife conization and no evidence of dysplasia on reevaluation were followed up for 1 to 18 years. Dysplasia was detected in one patient during cytologic surveillance. In phase II, 11 patients were followed up for 12 to 31 months; only one patient has dysplasia. CONCLUSION: Selected patients with squamous cell dysplasia at endocervical cone biopsy margins may avoid additional surgery.  相似文献   
836.
OBJECTIVE: To study noninvasively the functional anatomy and pathophysiologic characteristics of the globus pallidus external (GPe) and internal (GPi) divisions. DESIGN: Structural and functional neuroimaging using high-resolution magnetic resonance imaging. SETTING: University medical center research facility. SUBJECTS. Seven patients with pallidal lesions, 4 with an akinetic-rigid syndrome and 3 with a dystonic syndrome, and 15 age-matched volunteers. MAIN OUTCOME MEASURES: T2-weighted anatomical magnetic resonance imaging and number of activated voxels in the GP during rapid supination and pronation of the hand. RESULTS: T2-weighted images showed hyperintense bilateral lesions in the GP of all patients. Patients with dystonic syndromes had isolated lesions in the GPi. Patients with signs of akinetic-rigid syndromes showed abnormalities in the GPe or in central portions of the GP (GPc). Patients with lesions in both parts of the GP had akinetic-rigid or dystonic syndromes. All patients showed activation in the areas of the lesions. The number of activated voxels in the GP was significantly smaller (P < .005, Wilcoxon signed rank test) in patients than in control subjects. Activation of the GP was predominantly contralateral to the moving hand. CONCLUSIONS: Lesions in the GPi result in a loss of inhibitory pallidal projections to the thalamus, which may explain the hyperkinetic signs. Lesions in the GPe lead to an increased inhibition of the thalamus, which may explain the hypokinetic signs. Neuronal activation in lesion sites suggests the presence of remaining functionally vital tissue.  相似文献   
837.
BACKGROUND: Recognition of a cervical spine injury is important to prevent further injury and in planning for future care. The management of the patient with a possible cervical spine injury who remains unresponsive is controversial. METHODS: A retrospective evaluation of obtunded trauma patients admitted to the surgical intensive care unit who underwent bedside fluoroscopic cervical spine evaluation. Fluoroscopic findings and all complications were noted. RESULTS: Twenty obtunded patients with possible cervical spine injuries underwent bedside fluoroscopic cervical spine evaluation. All patients had at minimum a normal three-view cervical spine series before fluoroscopy. Thirteen patients (65%) had the fluoroscopic examination completed at the bedside and were cleared. The complete cervical spine could not be evaluated in six patients (30%). One patient (5%) was found to have a C4-5 subluxation in the bedside examination. None of the patients had progression of their neurologic symptoms after cervical spine flexion/extension, and none developed evidence of spinal cord injury after being cleared during their hospital course. Cervical collars remained in place for 5.7+/-1.41 days (range, 1- 26 days). Three patients (15%) were noted to have decubiti under the cervical collar. CONCLUSION: In this small study, the use of bedside fluoroscopy to evaluate the cervical spine appears safe and easy to perform. One unrecognized injury was identified. The technique is usually successful and gives reassurance that a significant cervical spine injury is not present.  相似文献   
838.
PURPOSE: Urethral obstruction following a stress incontinence procedure occurs in 5 to 20% of patients. We examine the success of transvaginal urethrolysis in resolving voiding dysfunction. MATERIALS AND METHODS: A retrospective chart review was performed on 39 patients who had undergone transvaginal urethrolysis for urethral obstruction following an anti-incontinence procedure. Preoperatively, a history was taken, and pelvic examination and either video urodynamics or cystoscopy were done. RESULTS: All 39 patients complained of urge incontinence, 13% had urinary retention, 51% had incomplete bladder emptying and 36% voided to completion but had irritative voiding symptoms. Previous surgery included retropubic urethropexy in 41% of the cases, pubovaginal sling in 38% and bladder neck suspension in 21%. Mean length of followup after urethrolysis was 16 months. Of the 39 patients 33 (85%) had resolution of urge incontinence but 5 still required occasional intermittent catheterization. The remaining 6 patients had continued urge incontinence. An augmentation procedure was performed in 4 patients with improvement of symptoms. CONCLUSIONS: Our data support transvaginal urethrolysis for the treatment of iatrogenic urethral obstruction. It is a rapid, effective and minimally invasive technique that should be considered if voiding dysfunction does not resolve spontaneously.  相似文献   
839.
Pulmonary epithelial cell destruction in mice infected with PR8-A influenza virus has been studied with light and electron microscopy and enzyme histochemistry, and correlated with pulmonary surfactant activity. All epithelial cell types were infected by the virus, resulting in destruction, pneumonitis, and atelectasis by seven to ten days. Pulmonary surfactant activity decreased progressively following onset of infection, and was minimal by seven to ten days. Before types 1 and 2 alveolar pneumocytes regenerated, the regenerating bronchial cells grew peripherally into some of the denuded alveolar ducts and alveoli to form epithelial nodules. Eventually the types 1 and 2 pneumocytes regenerated to cover the alveolar surfaces that were not invaded by bronchial epithelium. This regeneration was associated with increased surfactant activity in the postinfluenzal lesions, suggesting that the type 2 pneumocytes are a source of surfactant.  相似文献   
840.
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