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71.
PURPOSE OF STUDY: To assess whether selected periapical radiographs, taken according to High Yield Criteria, can reveal as much intra-osseous pathology as universal panoramic screening. POPULATION STUDIED: The records of 1101 RAF recruits enlisted in 1988-89, average age 19 years (range 16-26). METHODS: The clinical records and bitewing radiographs of the recruits were examined and the requirement for periapical radiographs determined according to high yield criteria. A template, cut out to simulate the area covered by a periapical bitewing radiograph, was placed over the suspect region on the panoramic film and any findings found within the template recorded. The entire dental panoramic tomograph was then examined on a masked screen under 2X magnification and any further findings recorded. FINDINGS: There was a considerable number of findings reported, including three large isolated radiolucent areas, 75 periradicular radiolucent areas, four probable cysts and 1187 unerupted mandibular third molars. However, when the clinical significance of these 'lesions' was assessed only those related to dental causes appeared to have significant clinical implications and the results indicated that these could have been detected by selective radiology. CONCLUSION: This study showed that the only pathology which occurs frequently enough to justify radiographic screening of the jaws in young adults is related to teeth. It seems probable that this type of pathology can be at least as well detected by selective periapical screening, using high yield criteria, as is possible by universal panoramic screening.  相似文献   
72.
The ability to visualize cell motility occurring deep in the context of opaque tissues will allow many currently intractable issues in developmental biology and organogenesis to be addressed. In this study, we compare two-photon excitation with laser scanning confocal and conventional digital deconvolution fluorescence microscopy, using the same optical configuration, for their ability to resolve cell shape deep in Xenopus gastrula and neurula tissues. The two-photon microscope offers better depth penetration and less autofluorescence compared to confocal and conventional deconvolution imaging. Both two-photon excitation and confocal microscopy also provide improved rejection of "out-of-focus" noise and better lateral and axial resolution than conventional digital deconvolution microscopy. Deep Xenopus cells are best resolved by applying the digital deconvolution method on the two-photon images. We have also found that the two-photon has better depth penetration without any degradation in the image quality of interior sections compared to the other two techniques. Also, we have demonstrated that the quality of the image changes at different depths for various excitation powers.  相似文献   
73.
In this report, we conducted a secondary analysis of the Treatment of SSRI-Resistant Depression in Adolescents (TORDIA) study to explore the impact of specific cognitive–behavioral therapy (CBT) treatment components on outcome. In TORDIA, 334 youths (ages 12 to 18 years) with major depressive disorder who had failed to respond to an adequate course of selective serotonin reuptake inhibitor (SSRI) medication were randomized to a medication switch (either to an alternative SSRI or venlafaxine) with or without 12 weeks of adjunctive CBT. Participants who had more than 9 CBT sessions were 2.5 times more likely to have adequate treatment response than those who had 9 or fewer sessions. CBT participants who received problem-solving and social skills treatment components, controlling for number of sessions and other confounding variables, were 2.3 and 2.6 times, respectively, more likely to have a positive response. These preliminary findings underscore the importance of receiving an adequate number of sessions to attain an adequate clinical response. Finally, social skills and problem solving may be active elements in CBT for adolescent depression and should be considered in treatment by those working with seriously depressed youths. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
Six patients diagnosed with obstructive sleep apnea completed titration of an adjustable oral appliance, called the Silencer, during a single night of polysomnography. This protocol allowed for rapid titration of the oral appliance and effective treatment of sleep apnea. Variables which showed improvement included frequency of obstructive events, oxyhemoglobin saturation and snoring. Dental appliance adjustments with the silencer device can be made within three minutes. We have demonstrated that incremental mandibular advancement and repositioning allow us to determine the most effective jaw position to treat sleep apnea and snoring, which is also most likely to be tolerated by the patient.  相似文献   
75.
OBJECTIVE: For the adjustment of individual vancomycin dosages, we estimate the important pharmacokinetic quantities half-life, clearance, and volume of distribution. MATERIAL: To obtain reliable information 293 observations from 244 patients were extracted from 23 published studies on vancomycin. Information about vancomycin's pharmacokinetics out of different sources represents an increase in sample size and, therefore, interpretive power. METHODS: Once the whole of the data had been stratified into a small number of homogeneous clusters based on cofactors, different (robust) estimators (mean, median, Winsorized, and trimmed mean) were calculated for the expected value of the pharmacokinetic parameters of vancomycin within the clusters. Measures of the statistical accuracy such as standard error, bias, mean square error, and confidence interval were estimated via bootstrap methods from large bootstrap sample sizes to compare the quality of the estimators. RESULTS: Due to the homogenization of the data all individual estimator functions yield very similar results and the empirical mean works fairly well as an estimate. The most frequently used estimator with the smallest estimated mean square error was the Winsorized mean.  相似文献   
76.
It has been known for a long time that subcortical input drives the specification of cortical areas. Molecular signals mediating this instructive effect from the periphery are poorly understood. In foetal or neonatal rats, ablation of whisker follicles, transection of the infraorbital nerve, inhibition of axonal transport, but not impulse activity blockade, prevent formation of barrels in the primary somatosensory cortex (S1). These findings suggest that a chemical signal, possibly arising from the skin or the follicle, may be responsible for somatotopic pattern formation in S1. Neurotrophins promote survival and differentiation of primary sensory neurons, and are expressed in the whisker pad during development. Neonatal rats received gelfoam impregnated with NGF, BDNF or NT-3 under the whisker pad following surgical denervation of whisker rows D and E on P0. Barrel formation in S1 was assessed on P7 by acetylcholinesterase histochemistry and 5-HT-immunohistochemistry. BDNF and NT-3, but not NGF, promoted development of the cortical barrels corresponding to denervated whiskers. Furthermore, BDNF and NT-3 prevented the lesion-induced expansion of row C barrels, while NGF appeared to promote row C expansion. Our results suggest that BDNF and NT-3 arising from the whisker pad are involved in the formation and/or maintenance of the barrel pattern in S1. These findings are potentially relevant for the prevention of sensory disturbances possibly due to reorganization of central sensory circuits after peripheral nerve lesions in humans.  相似文献   
77.
BACKGROUND: Nephrolithiasis may be an important consequence of indinavir therapy; however little has been published on the variation in incidence between different populations of patients or the possible mechanisms of calculus formation. OBJECTIVE: To examine variation in the incidence of indinavir-associated nephrolithiasis (IAN) in HIV-positive patients in relation to hemophilia and hepatitis C virus (HCV) infection. METHODS: Clinical data were abstracted retrospectively from the medical records of all adult patients treated with indinavir from September 1995 to September 1997. Occurrence of first IAN, defined as flank pain and hematuria after initiation of therapy, was analyzed in relation to hemophilia status and HCV infection. RESULTS: There were 17 episodes of IAN (22%) among 79 patients treated with indinavir. Of 10 patients with hemophilia, 50% developed IAN as compared with 17% of patients without hemophilia (P = 0.03). Median days to first IAN was 22 (range 7-110 days) for hemophiliacs and 156 (range 5-611 days) for those without hemophilia. Data for HCV status were available for 74 out of 79 patients: 10 out of 27 (37%) patients with HCV developed IAN compared with six out of 42 (14%) without HCV (P = 0.02). CONCLUSION: Overall incidence of IAN was higher than that previously reported and was significantly greater in hemophiliacs than in non-hemophiliacs. HCV may be a contributing factor.  相似文献   
78.
Inhibition of the nuclear export of poly(A)-containing mRNAs caused by the influenza A virus NS1 protein requires its effector domain. Here, we demonstrate that the NS1 effector domain functionally interacts with the cellular 30 kDa subunit of CPSF, an essential component of the 3' end processing machinery of cellular pre-mRNAs. In influenza virus-infected cells, the NS1 protein is physically associated with CPSF 30 kDa. Binding of the NS1 protein to the 30 kDa protein in vitro prevents CPSF binding to the RNA substrate and inhibits 3' end cleavage and polyadenylation of host pre-mRNAs. The NS1 protein also inhibits 3' end processing in vivo, and the uncleaved pre-mRNA remains in the nucleus. Via this novel regulation of pre-mRNA 3' end processing, the NS1 protein selectively inhibits the nuclear export of cellular, and not viral, mRNAs.  相似文献   
79.
Cystic fibrosis is a common and potentially life-threatening hereditary disease which can affect numerous organs, particularly the digestive tract. CASE REPORT: A 4.5-year-old boy exhibited two little known clinical manifestations: an appendiceal mucocele and repeated intussusceptions. In spite of an appendectomy, intussusception relapsed and an ileocolic resection was necessary 2 years later. DISCUSSION: Appendiceal diseases in cystic fibrosis represent a large spectrum, ie, distention on the appendiceal lumen, engorged with sticky mucous matter, which becomes an appendiceal mucocele, peritonitis with an appendiceal perforation due to delayed diagnosis since acute appendicitis is difficult to diagnose in these patients. Intussusception is rarely observed in cystic fibrosis. CONCLUSION: Appendiceal mucocele could be a cause of intussusception. If an appendectomy is performed, resection of a part of the cecum, around the appendix, could be useful in preventing again mucocele formation.  相似文献   
80.
The Chiari type II malformation is the leading cause of death in infants with myelomeningocele. The authors report 17 cases of symptomatic Chiari type II malformation occurring in two distinct age dependent population. In Group I, 13 neonates and infants in the first year of life presented with cranial nerve and brain stem dysfunction characterized by vocal cord paralysis, apnea, dysphagia and laryngeal stridor. In Group II, 4 patients developed signs and symptoms after the first year of life. In this group, the presentation was more insidious and included neck pain and cerebellar manifestations. The surgical treatment consisted initially in shunt implantation or revision and when there was no improvement, posterior fossa decompression was performed. The response to the surgical treatment differed considerably between the two groups: older patients improved promptly after surgery and there was no casualties; in newborn and infants, especially those under 6 months of age, the mortality rate was 46.1%. The authors stress that prompt diagnosis and surgical intervention should be performed in order to produce a favorable outcome.  相似文献   
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