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1.
OBJECTIVES: An International Workshop addressed the prevalence and classification of HIV/AIDS associated oral lesions.
DESIGN: Five questions provided the framework for discussion and literature review. What is the prevalence of oral lesions in children and adults? Should the accepted classification of HIV-related oral lesions be modified in the light of recent findings? Why is there a gender difference in the prevalence of oral lesions in developed and developing countries? Are there unusual lesions present in developing countries? Is there any association between modes of transmission and the prevalence of oral lesions?
RESULTS: Workshop discussion emphasized the urgent need for assistance in the development of expertise to obtain accurate global prevalence data for HIV-associated oral lesions. Oral candidiasis has been consistently reported as the most prevalent HIV-associated oral lesion in all ages. Penicilliosis marneffei, a newly described fungal infection, has emerged in South-east Asia. Oral hairy leukoplakia and Kaposi's sarcoma appear to be associated with male gender and male-to-male HIV transmission risk behaviours. These lesions occur only rarely in children.
CONCLUSIONS: Additional prevalence data are needed from developing countries prior to substantially altering the 1993 ECC/WHO Classification of oral lesions associated with adult HIV infection. The workshop confirmed current oral disease diagnostic criteria.  相似文献   
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The PET tracer [11C]5-hydroxytryptophan ([11C]5-HTP), which is converted to [11C]5-hydroxytryptamine ([11C]5-HT) by aromatic amino acid decarboxylase (AADC), is thought to measure 5-HT synthesis rates. But can we measure these synthesis rates by kinetic modeling of [11C]5-HTP in rat? Male rats were scanned with [11C]5-HTP (60 minutes) after different treatments. Scans included arterial blood sampling and metabolite analysis. 5-HT synthesis rates were calculated by a two-tissue compartment model (2TCM) with irreversible tracer trapping or Patlak analysis. Carbidopa (inhibitor peripheral AADC) dose-dependently increased [11C]5-HTP brain uptake, but did not influence 2TCM parameters. Therefore, 10 mg/kg carbidopa was applied in all subsequent study groups. These groups included treatment with NSD 1015 (general AADC inhibitor) or p-chlorophenylalanine (PCPA, inhibitor of tryptophan hydroxylase, TPH). In addition, the effect of a low-tryptophan (Trp) diet was investigated. NSD 1015 or Trp depletion did not affect any model parameters, but PCPA reduced [11C]5-HTP uptake, and the k3. This was unexpected as NSD 1015 directly inhibits the enzyme converting [11C]5-HTP to [11C]5-HT, suggesting that trapping of radioactivity does not distinguish between parent tracer and its metabolites. As different results have been acquired in monkeys and humans, [11C]5-HTP-PET may be suitable for measuring 5-HT synthesis in primates, but not in rodents.  相似文献   
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个性化颅骨成形术中植入材料类型与颅骨缺损面积的关系   总被引:2,自引:0,他引:2  
目的:分析个性化颅骨成形术中,植入材料类型与颅骨缺损面积的关系。 方法:选择解放军总医院第二附属医院神经外科2002-03/2005-01和河北省三河市医院神经外科2003-09/2005-04收治的资料齐全的计算机辅助设计颅骨成形术患者75例,分为嵌入性材料(骨水泥、硅橡胶)组40例,根据颅骨缺损面积又分为大面积(≥36cm2)组17例和小面积(〈36cm2)组23例;覆盖性材料(钛网)组35例,大面积组14例和小面积组21例。采用头颅CT超薄扫描(层厚1.5mm),三维重建,模拟缺损颅骨补片,应用激光快速成形技术,制作缺损颅骨及颅骨补片模型,患者认可后,根据患者的病情应用硅橡胶、骨水泥、钛网作为植入材料,进行手术植入。术后1周观察并发症:头痛、积液、松动。 结果:75例患者的补片与颅骨完整适配,塑形满意,术中无需修整,平均手术时间45min,83%(63/75)患者感到基本或完全恢复了原有容貌。手术并发症:嵌入性材料组头痛4例,积液10例,松动2例,共16例,其中大面积组13例,小面积组3例;覆盖性材料组头痛1例,积液2例,松动0例,共3例次,其中大面积组2例,小面积组1例。应用精确概率分析,两材料组之间手术并发症差异显著,两材料组颅骨缺损面积之间手术并发症差异显著,嵌入性材料大面积组与覆盖性材料大面积组之间手术并发症差异显著,嵌入性材料小面积组与覆盖性材料小面积组之间手术并发症无显著性差异。 结论:个性化设计的颅骨修补材料,能够最大限度的恢复患者外形,缩短手术时间,大面积的颅骨缺损应用钛网修补,小面积的应用钛网和嵌入性材料修补。根据患者颅骨缺损面积,选择不同植入材料,可以提高手术疗效,减少术后并发症。  相似文献   
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Isolated headache as the presenting clinical manifestation of intracranial tumors: a prospective study. Cephalalgia 1994;1'4:270-1. Oslo. ISSN 0333-1024We prospectively studied over two years the incidence of headache as the initial and isolated clinical manifestation of adult patients suffering from intracranial tumors ( n = 183). Fifteen patients (8%) exhibited headache as their first and isolated clinical manifestation. Age, sex, neoplasm localization, or pathological diagnosis did not correlate with the presence of headache. Posterior fossa location and hydrocephalus, though not reaching statistical significance, were more frequent in patients who presented with headache as the first symptom. At the moment of diagnosis, 59 (31%) of the patients admitted to headache, though only I out of the 15 patients starting as headache still had this symptom as the only manifestation. From our experience in adults, isolated headache for longer than 10 weeks will only exceptionally be secondary to an intracranial neoplasm.  相似文献   
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Background  

The authors examined factors associated with nutritional resilience/vulnerability among preschoolers in the Gaza Strip in 2007, where political violence and deprivation are widespread.  相似文献   
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Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization.  相似文献   
10.
The aim of our study is to investigate whether single-nucleotide dystrophin gene (DMD) variants associate with variability in cognitive functions in healthy populations. The study included 1240 participants from the Erasmus Rucphen family (ERF) study and 1464 individuals from the Rotterdam Study (RS). The participants whose exomes were sequenced and who were assessed for various cognitive traits were included in the analysis. To determine the association between DMD variants and cognitive ability, linear (mixed) modeling with adjustment for age, sex and education was used. Moreover, Sequence Kernel Association Test (SKAT) was used to test the overall association of the rare genetic variants present in the DMD with cognitive traits. Although no DMD variant surpassed the prespecified significance threshold (P<1 × 10−4), rs147546024:A>G showed strong association (β=1.786, P-value=2.56 × 10−4) with block-design test in the ERF study, while another variant rs1800273:G>A showed suggestive association (β=−0.465, P-value=0.002) with Mini-Mental State Examination test in the RS. Both variants are highly conserved, although rs147546024:A>G is an intronic variant, whereas rs1800273:G>A is a missense variant in the DMD which has a predicted damaging effect on the protein. Further gene-based analysis of DMD revealed suggestive association (P-values=0.087 and 0.074) with general cognitive ability in both cohorts. In conclusion, both single variant and gene-based analyses suggest the existence of variants in the DMD which may affect cognitive functioning in the general populations.  相似文献   
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