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991.
OBJECTIVE: Intracranial papillary endothelial hyperplasia (PEH) is rare, and only 13 cases have been reported intracranially in the literature. In this article, we present a case of PEH involving petrous and jugular foramen region due to the uncommon incidence. CASE DESCRIPTION: A 49-year-old female patient with a 4-year history of left-sided hearing loss and facial palsy. Magnetic resonance (MR) imaging disclosed the presence of a 6 x 6 x 5 cm lobular mass occupying the left petrous and jugulare region. This mass was hyperintense on both T1 and T2 weighted MR images and was enhanced strongly with gadolinium. No edema was found around the lesion. Preoperative digital subtraction angiogram examination showed that the lesion had a rich blood supply. Therefore, polyvinyl alcohol embolization was carried out to reduce bleeding during operation. A left-sided suboccipital extreme lateral approach was applied for craniotomy. The lesion was extradural and highly vascular with extension into the petrous bone. It was subtotally removed. Postoperative course of the patient was stable. Her neurologic evaluation was the same as preoperatively. CONCLUSION: Surgical excision of the lesion is the main therapy. Radiotherapy should be given to patients whose lesion cannot be totally removed. 相似文献
992.
Evaluation of adrenalectomy in patients diagnosed with ectopic ACTH syndrome was studied. Twenty-three clinical cases diagnosed with ectopic ACTH syndrome were analyzed at Chinese Academy of Medical Sciences and Peking Union Medical College Hospital (PUMCH). Cases consisted of 14 males and 9 females, with mean age of 38 years. All 23 cases had positive clinical, biochemical and radiology evidence for diagnosis of Cushing's syndrome. Sixteen of the 23 cases were treated with total adrenalectomy and the remaining 7 were treated without surgical intervention. Sixteen cases, having no identifiable source of ectopic hormone production, experienced resolution of presenting signs and symptoms after undergoing bilateral or unilateral total adrenalectomy; 1-year survival was 67%, 2-year survival 41% and 5-year survival 15%. In patients treated conservatively without surgical intervention, 1-year survival was 0%. In patients with no identifiable source of ectopic hormone production, bilateral adrenalectomy followed by hormone replacement treatment is effective. 相似文献
993.
Van de Ven P Mao L Crawford J Prestage G Grulich A Kaldor J Kippax S 《International journal of STD & AIDS》2005,16(4):314-317
This study aimed to determine and describe HIV-negative gay men's willingness to participate in HIV vaccine trials. Data were from participants who completed face-to-face interviews during the first 18 months (to the end of 2002) of recruitment into the Health in Men cohort of HIV-negative gay men in Sydney. A key outcome measure was a scale of Willingness to Participate in HIV Vaccine Trials, with scores ranging from 1 (unwilling) to 4 (willing). The 903 participants ranged in age from 18 to 75 years (median = 36). Mean of Willingness to Participate in HIV Vaccine Trials was 2.53 (standard deviation = 0.54), with approximately 51% of the men having a score greater than the midpoint of 2.50. A reduced linear regression model yielded four significant independent associations with Willingness to Participate in HIV Vaccine Trials: lack of tertiary education (P < 0.001),having engaged 'in the previous six months' in any unprotected anal intercourse with casual or non-concordant regular partners (P < 0.001), higher self-rated likelihood of HIV infection (P < 0.01), and higher mean scores on a scale of Comfort with Participation in HIV Vaccine Trials (P < 0.001). The willingness of HIV-negative gay men at potentially higher risk for HIV to participate in HIV vaccine trials augurs well for enrolment in HIV vaccine efficacy trials. Recruitment into trials is likely to be enhanced by addressing salient concerns such as confidentiality and vaccine-induced antibody positivity. Also, it will be important to ensure that gay men are educated and fully informed about HIV vaccines and trial processes. 相似文献
994.
Pharmacology and pharmacokinetics of the antiviral agent beta-D-2',3'-dideoxy-3'-oxa-5-fluorocytidine in cells and rhesus monkeys
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995.
Early intervention is a group cooperative medical service. This article aims to illustrate the knowledge required by nurses who intend to practice in areas of early intervention. The contents consist of definitions, laws, and current practices in early intervention in Taiwan and the United States. In addition, the roles and responsibilities of nurses in transdisciplinary early intervention teams will also be introduced. This article will serve as an introduction for nurses practicing early intervention. We would also encourage the addition of the knowledge that it introduces to continuing education programs to enhance nurses' abilities in the screening and management of cases. 相似文献
996.
Mohammad Y Hajeer Zhili Mao Declan T Millett Ashraf F Ayoub Jan Paul Siebert 《The Cleft palate-craniofacial journal》2005,42(2):113-120
OBJECTIVE: To validate a new method of facial volumetric assessment that is dependent on the use of stereophotogrammetric models and a software-based Facial Analysis Tool. DESIGN: The method was validated in vitro with three-dimensional (3D) models of a lifelike plastic female dummy head and in vivo with a male-subject head. METHODS: Thirty facial silicone explants were added in the nasal and perioral regions of each head, and their volumes were obtained by three different algorithms. These were compared with the actual values obtained by a "water displacement" method. RESULTS: The least mean error was found with the "tetrahedron formation" method followed by the "projection" method and the "back-plane construction" method. The error with the tetrahedron formation method was 0.071 cm(3) (95% confidence interval [CI]: -0.074 to 0.2161 cm3) with the in vitro models and 0.314 cm3 (95% CI: -0.080 to 0.708 cm3) with the in vivo models. The increased volumetric assessment error observed in vivo was attributed to the registration procedure and possible changes in facial expression. CONCLUSIONS: These results encourage the use of this method in the 3D assessment of orthognathic surgical outcome, provided a standardized facial expression is used for image acquisition. 相似文献
997.
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999.
Repeated vivid recalls or flashbacks of traumatic memories and memory deficits are the cardinal features of post-traumatic stress disorder (PTSD). The underlying mechanisms are not fully understood yet. Here, we examined the effects of very strong fear conditioning (20 pairings of a light with a 1.5-mA, 0.5-s foot shock) and subsequent reexposure to the conditioning context (chamber A), a similar context (chamber B), and/or to the fear conditioned stimulus (CS) (a light) on synaptic plasticity in the hippocampal CA1 area in anesthetized Sprague-Dawley rats. The conditioning procedure resulted in very strong conditioned fear, as reflected by high levels of persistent freezing, to both the contexts and to the CS, 24 h after fear conditioning. The induction of long-term potentiation (LTP) was blocked immediately after fear conditioning. It was still markedly impaired 24 h after fear conditioning; reexposure to the conditioning chamber A (CA) or to a similar chamber B (CB) did not affect the impairment. However, presentation of the CS in the CA exacerbated the impairment of LTP, whereas the CS presentation in a CB ameliorated the impairment so that LTP induction did not differ from that of control groups. The induction of long-term depression (LTD) was facilitated immediately, but not 24 h, after fear conditioning. Only reexposure to the CS in the CA, but not reexposure to either chamber A or B alone, or the CS in chamber B, 24 h after conditioning, reinstated the facilitation of LTD induction. These data demonstrate that unconditioned and conditioned aversive stimuli in an intense fear conditioning paradigm can have profound effects on hippocampal synaptic plasticity, which may aid to understand the mechanisms underlying impairments of hippocampus-dependent memory by stress or in PTSD. 相似文献
1000.
We sought to identify the neural substrates underlying perceptual grouping, and examined whether the grouping-related neural activities are modulated by task relevance and attention by recording high-density event-related potentials (ERPs). Participants were presented with stimulus arrays, in which local elements were either evenly distributed or grouped into rows or columns by proximity or similarity, and had to discriminate orientations of the perceptual groups, or to identify the colors of dots around stimulus displays or of the fixation cross. We found that proximity grouping was indexed by a positive activity over the medial occipital cortex with a peak latency of about 100 ms after stimulus onset (Pd100), whereas grouping by similarity of shape was reflected in a negative activity with longer latency over the occipito-temporal areas. Dipole modeling based on a realistic boundary element head model localized the Pd100 to the right calcarine cortex. Moreover, we showed that the grouping-related activities were weakened when stimulus arrays were of low task relevance and fell outside an attended area of field. The results suggest that human calcarine cortex is engaged in early grouping operations defined by proximity, reinforcing the previous fMRI findings. Moreover, our ERP results indicate that the neural bases underlying perceptual grouping in human visual cortex can be modulated by task relevance and attention as early as 100 ms after sensory stimulation. Hum Brain Mapp, 2005. (c) 2005 Wiley-Liss, Inc. 相似文献