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BACKGROUND: Psychotic symptoms in Alzheimer disease (AD+P) identify a heritable phenotype associated with more rapid cognitive decline. The authors have proposed that AD+P is itself a composite of a misidentification and a paranoid subtype with increased cognitive impairment restricted to the misidentification type. Most prior studies of the clinical correlates of AD+P have been limited, however, by the inclusion of prevalent cases. METHODS: Subjects with possible or probable AD or mild cognitive impairment (MCI) without psychosis at study entry were assessed at the time of initial presentation and then annually. Psychotic symptoms were assessed using the CERAD Behavioral Rating Scale. Survival analyses used Cox proportional hazard models with time-dependent covariates to examine the predictors of psychosis onset. RESULTS: A total of 288 subjects completed at least one follow-up examination. Mean duration of follow-up was 22.1 months. The incidence of psychosis was 0.19 per person-year. Cognitive impairment was associated with onset of psychosis, largely as a result of its association with onset of the misidentification, but not the paranoid, subtype. Including psychotropic medication use in the model revealed an association of antidepressant use with the onset of psychosis. This latter association appeared to arise from an underlying association between depression and the risk of psychosis onset rather than from antidepressant treatment. CONCLUSION: These findings are consistent with the hypothesis that the misidentification and the paranoid subtypes each define a more biologically homogeneous group than AD+P as a whole. Further exploration of the relationship between depressive symptoms and psychosis in patients with AD is warranted.  相似文献   
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During the development of motor vagal nuclei (MVN), the neuroblasts of the myeloencephalic basal plate migrate in the dorsolateral direction to form the dorsal motor vagal nucleus (DMVN) and ventrolaterally to form the ventral motor vagal nucleus (VMVN). Those neuroblasts that remain close to the median sulcus will form the hypoglossal nucleus. In support of the congenital origin of the alteration of the MVN in sudden infant death syndrome (SIDS), we report the case of an 8‐month‐old female child who was found dead in her cot. The neuropathological assessment revealed that the medullary triangle of the 4th ventricle floor was asymmetric, owing to the presence of three prominences to the left side of the median sulcus. The medial prominence corresponded to the hypoglossal nucleus, which showed a marked increase in the number of large neurons; the intermediate prominence corresponded to the DMVN whose large neurons were reduced and were recognizable mainly at the level of the medial fringe; the lateral prominence corresponded to the solitary nucleus. The left solitary tract showed a reduction of the transverse diameter. Also, the left VMVN showed marked reduction in the number of neurons. Inflammatory and astrocytic reactions were absent. We suggest that in SIDS cases the hypocellularity of the MVN and the increased number of neurons of the hypoglossal nucleus are intimately related, indicating a congenital alteration due to incomplete migration of the vagal neuroblasts with abnormality of the autonomic cardio‐respiratory control.  相似文献   
4.
PURPOSE: This study retrospectively evaluated the soft tissue healing after using parasagittal soft tissue incisions for surgical segmental maxillary expansion. PATIENTS AND METHODS: The records of 311 patients (224 females, 87 males), with an average age of 28.5 years (range, 12 to 62 years) who had transverse maxillary hypoplasia, were retrospectively evaluated. All patients underwent segmental maxillary osteotomies, surgical maxillary expansion greater than 5 mm, and placement of midpalatal porous block hydroxyapatite (PBHA). Parasagittal palatal soft tissue incisions were used to facilitate expansion, minimize soft tissue damage, and maintain soft tissue coverage over the PBHA implants. At postoperative follow-up visits, any signs or symptoms of complications associated with the use of the parasagittal incisions were recorded. RESULTS: Average patient follow-up was 3.4 years (range, 1.0 to 7.2 years). In 293 patients (94%), the palates healed uneventfully without complications. Eighteen patients (6%) had complications; 9 (2.9%) had infections associated with the midpalatal implants, 8 (2.6%) had oronasal communications, and 1 (0.3%) had problems associated with a palatal wire. Six patients with midpalatal implant problems required removal of the implant, 4 patients required closure of their oronasal communications, and 1 patient required removal of a palatal wire. Therefore, 11 patients (3.5%) required minor secondary surgical procedures. No teeth or alveolar bone were lost in any of the cases. CONCLUSIONS: The use of parasagittal palatal incisions appears to be a safe technique for soft tissue management during large surgical maxillary expansions associated with segmental maxillary osteotomies and midpalatal placement of PBHA implants.  相似文献   
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de Caro  R.  Parenti  A.  Capitanio  G.  Ori  C.  Bracco  F.  Ricchieri  G. L. 《Acta neurochirurgica》1990,104(1-2):73-76
Summary A vascular malformation, consisting of a venous vessel bridgeing the right inferior petrosal sinus and the anterior spinal veins, was found in the posterior fossa. The vessel presented a ring-like course around the right trigeminal root, and it was parallel and dorsal to the basilar artery. The malformation was associated with cutaneous and hepatic angiomas and peri-osteal lipomas. It had been clinically silent for 52 years, when it thrombosed causing death. The authors think that, within a general mesenchymopatic state, this is a result of the persistence of an embryonal cerebral venous pattern.  相似文献   
7.
1. Eight conscious rabbits were repeatedly subjected to progressive reduction in central blood volume by gradually inflating a thoracic inferior vena caval-cuff so cardiac index (CI) fell at a constant 8.5% of baseline/min. 2. Caval-cuff inflations were performed after 10 min exposure to 100, 21, 12–14 and 8–10% O2, with and without the addition of 3–4% CO2, in randomized order. 3. The haemodynamic response to progressive reduction in central blood volume was biphasic. In Phase I, systemic vascular conductance index (SVCI) fell linearly, supporting mean arterial pressure (MAP). When CI had fallen to a critical level, Phase II occurred in which SVCI rose abruptly, MAP plummeted and respiratory drive progressively increased. 4. During Phase I, there were independent linear relationships between Pao2 (but not Pao2) and the rates at which SVCI and MAP changed during the progressive fall of CI. The higher the level of Pao2, the greater was the rate of fall of SVCI and the less the rate of fall of MAP. 5. There was an inverted U-shaped effect of Pao2, on the level of CI at which Phase II occurred: (a) during hyperoxia (100% O2), Phase II occurred later than during normoxia (21% O2); and (b) across the normoxic and hypoxic gas mixtures (21–8% O2, with and without added CO2), there was an independent linear relationship between Pao2 (but not Pao2 or Pao2×Pao2) and the level of CI at which Phase II occurred. That is, the lower the level of Pao2, the later was the onset of Phase II. This interaction is best explained by an increased level of central sympathetic vasoconstrictor drive during hypoxia.  相似文献   
8.
Patients frequently present to the emergency room (ER) with mental status changes without obvious cause. The EEG is underused in this population. The authors investigated whether an abbreviated EEG (AbEEG) can be incorporated in the early evaluation of these patients to provide useful information. A 5-minute AbEEG was performed using a preformed electrode placement system on 25 patients who presented to the ER with mental status changes of unknown cause. AbEEG findings were categorized as normal, showing diffuse abnormalities, focal abnormalities, electrographic seizures, or uninterpretable. Using retrospective chart review, the authors determined if the cause of mental status change was a diffuse encephalopathy or a nonneurologic event (DENNE), a focal brain abnormality, nonconvulsive status epilepticus (NCSE), psychogenic, or unknown, and if particular AbEEG findings were associated with specific causes of altered sensorium. The AbEEG identified NCSE in two patients who presented with new-onset seizures. The presence of diffuse slowing on the AbEEG was highly suggestive of mental status changes due to DENNE. AbEEGs can be successfully incorporated in the early evaluation of patients who present to the ER with mental status changes of unknown cause and provide useful information in this setting.  相似文献   
9.
BACKGROUND: Pilonidal disease is a chronic disease of the natal cleft. Recurrent follicular infection is the causative factor. Surgical treatment has a significant failure rate, and recurrence is common. Laser removal of hair in the natal cleft could be an alternative to surgery. OBJECTIVE: To determine the effectiveness of laser hair removal in the natal cleft on pilonidal disease. METHODS: Six young men with recurrent pilonidal disease were treated with laser epilation in our clinic from 2000 to 2003. Most patients had a history of one or more surgical treatments in the area, and all patients had suffered recurrent folliculitis for years. An alexandrite laser was mostly used, although, occasionally, an intense pulsed light device was used. The number of epilation treatments ranged from 3 to 11, performed at 6- to 8-week intervals. RESULTS: All patients experienced progressive resolution of the folliculitis with the laser epilation treatments. No more surgical treatments have been needed. The treatments were simple and quick, and there were no complications. CONCLUSION: Laser epilation of the natal cleft should be considered a first choice treatment for recurrent pilonidal disease. Preventive laser epilation of the natal cleft in patients with recurrent folliculitis could avoid future surgery.  相似文献   
10.
The basilar artery is the only large artery in which two flows merge, and this is reflected in the flow downstream. We report quantitative flow — velocity measurements with a phase-based MR technique, i.e. the Fourier velocity encoding method, in the basilar artery of a volunteer. To our knowledge, this has not previously been performed successfully. A comparison is made with the results of flow velocity measurements in the basilar artery with transcranial Doppler ultrasonography; the techniques agreed very well. Although Doppler ultrasonography is still most widely used, no information on the flow rate and the flow velocity distribution in the basilar artery can be provided. MR flow measurement techniques appear promising when detailed information on the flow velocity distribution and flow rate is needed.  相似文献   
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