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Membrane trafficking processes are presumably vital for axonal regeneration after injury, but mechanistic understanding in this regard has been sparse. A recent loss-of-function screen had been carried out for factors important for axonal regeneration by cultured cortical neurons and the results suggested that the activity of a number of Rab GTPases might act to restrict axonal regeneration. A loss of Rab27b, in particular, is shown to enhance axonal regeneration in vitro, as well as in C. elegans and mouse central nervous system injury models in vivo. Possible mechanisms underlying this new finding, which has important academic and translational implication, are discussed.  相似文献   
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OBJECTIVE: Hypertension is an important problem of the public health. Insufficient education of the people along with insufficient physical examination also plays a role in the poor success of the diagnosis and treatment of the hypertension. We investigated whether the skinfold thickness has an importance in the prediction of blood pressure or not. METHODS: In Aydin City area 110 women and 100 men selected by randomized sampling method were included into our study. Body mass index, blood pressure and skinfold thickness were measured according to the international guidelines. RESULTS: There was a moderate correlation between the skinfold and body mass index (r= 0.494, p=0.000) and there was a mild correlation between the body mass index and systolic and diastolic blood pressures (r=0.225, p=0.000 and r=0.300, p=0.000, respectively). There was no correlation between the skinfold thickness and systolic and diastolic blood pressures (r=0.058, p=0.400 and r=0.090, p=0.194, respectively). CONCLUSION: It is concluded that body mass index, not skinfold thickness, can be used for the prediction of the blood pressure. Some other factors independent from the body mass index might be the determinants of the skinfold thickness.  相似文献   
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Treatment of Anogenital Warts by Pulsed Dye Laser   总被引:2,自引:0,他引:2  
BACKGROUND: Treatment of anogenital warts is difficult in that the disease spectrum is wide. Moreover, varying degrees of improvement are obtained. OBJECTIVE: To study the treatment of persistent anogenital warts by pulsed dye laser. METHODS: Pulsed dye laser was used with the following settings: spot size 7 mm, pulse duration 1500 microsec, and fluence 7.5 J/cm2. Two different wavelengths were used: 585 and 595 nm. RESULTS: Lesions healed completely using both wavelengths after one treatment. CONCLUSION: Pulsed dye laser has been found to be safe, effective, satisfactory, and less traumatic compared to other options for treatment of perianal warts in children.  相似文献   
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BACKGROUND AND PURPOSE: Mycoplasma pneumoniae infection is a frequent cause of community-acquired respiratory infections in children and adults. However, standardized, rapid, specific methods for its diagnosis are lacking. The relationship between M. pneumoniae infection and asthma exacerbation has been recently discussed in the literature. We investigated the accuracy of rapid detection of mycoplasma infection by cold hemagglutination test compared to conventional enzyme immunoassays. The clinical characteristics of mycoplasma infection seen during emergent visits in asthmatic children were reviewed. METHODS: We retrospectively reviewed medical records of patients with asthma exacerbation visiting the Department of Pediatric Emergency, National Taiwan University Hospital, over a 12-month period. Subjects 2-18 years of age diagnosed with asthma at our outpatient clinic were included in this study. Patients with immunodeficiency, congenital anomalies, neurological diseases and irregular follow-up were excluded. RESULTS: A total of 269 children (174 males and 95 females) with a mean (+/- standard deviation) age of 6.15 +/- 3.08 years were included. The prevalence of asthma exacerbation in regular follow-up patients was 13.4%, and as many as 19.6% of cases (74/378 person-times) required hospitalization. Asthma attacks were most prevalent during December. 126 patients had both rapid cold hemagglutination testing and mycoplasma immunoglobulin M titers determined using acute blood samples drawn in the emergency room; 46 (36.5%) of these patients demonstrated mycoplasma infection. Sensitivity and specificity of the rapid cold hemagglutination test was 78.3% and 41.3%, respectively. The positive predictive value was 43.4%. Comparison of patients with or without mycoplasma infection revealed no differences in gender, age, chest X-ray findings, and most symptoms/signs and laboratory data, except that more signs of fever and auscultatory rales were seen in the non-mycoplasma infection group. CONCLUSIONS: Mycoplasma infections could be an exacerbating factor for asthma, and the rapid cold hemagglutination test should not be a guideline for prescribing macrolides in the emergency room.  相似文献   
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In reaction time (RT) tasks, event-related potentials (ERPs) reveal a response-locked negative wave when subjects commit errors. This wave, termed "error negativity" (Ne) or "error-related negativity" (ERN), is thought to index response-monitoring processes. With conventional monopolar recordings, this negativity is hardly seen on correct responses, likely overlapped by a large positive wave. Indeed, after Laplacian transformation (a spatial high-pass filter), a small Ne-like wave is unmasked. Recently, it has been shown that the positivity on monopolar recordings was larger for correct responses preceding an error than for correct responses preceding a correct trial. After Laplacian transformation, it appears that this effect is due, at least in part, to a decrease of the Ne-like wave on correct responses preceding an error. This result indicates that, as the Ne on errors, the Ne-like wave on correct responses is sensitive to performance and hence is likely related to response-monitoring processes.  相似文献   
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The Human Leukocyte Antigen (HLA) typing of large groups of patients with various autoimmune diseases has demonstrated that some HLA alleles occur at higher frequencies in specific diseases than in the general population. Chronic urticaria has been shown to have an autoimmune basis by a previous study which found an association between chronic urticaria and specific HLA groups. We investigated the HLA subtypes of Turkish chronic urticaria patients. For this purpose 42 Turkish patients with chronic urticaria and 115 healthy controls were typed for HLA-DR and DQ by PCR-SSP (Polymerase Chain Reaction Sequence Specific Primers) low resolution DNA technique. We found an increased frequency of DR4 (42.9%, p=0.01) in chronic urticaria patients in comparison with that in healthy controls. This study supports the hypothesis that HLA alleles may be involved in the pathogenesis of chronic urticaria and that they appear to be directly involved in the initiation of the immune response.  相似文献   
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Drug-resistant tuberculosis is a serious problem throughout the world. Resistance to Rifampicin (RIF) is mainly caused by the mutations in the rpoB gene coding the beta-subunit of RNA polymerase. In this study, we aimed to detect the distribution of rpoB gene mutations in 80 RIF-resistant clinical Mycobacterium tuberculosis (MTB) isolates from Turkey. The rpoB gene was amplified by PCR and mutations leading to RIF resistance were determined by automated sequence analysis. A total of 72 of the 80 isolates (90%) were found to carry mutations in the amplified region, whereas eight isolates (10%) carried no mutations. Overall, 24 different missense mutations affecting 14 codons, and two deletion mutants were identified. Nine new mutations, six in the hot-spot region and three outside this region, were found. The codon numbers of the most frequently encountered mutations were 531 (51.4%), 526 (18.1%), 516 (13.9%), and 513 (12.5%). As a result, 90% of the RIF-resistant MTB isolates from the Turkish patients were found to carry a mutation in the rpoB gene, Ser531Leu being the most frequent one. Although molecular methods identify mutations leading to RIF resistance very quickly, results of the antimycobacterial susceptibility tests must be taken into consideration for the patients carrying no mutations in this region.  相似文献   
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