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Each sport presents with unique risk factors and different mechanisms of injury, and therefore extrapolation of the data from one sport to another makes comparison difficult. The current evidence exploring the relationship of athletes and degenerative changes of the cervical spine leaves much to be debated, and future prospective longitudinal studies will be needed to clarify our understanding further. Such research will help structure clinical recommendations and improve sports safety and the care of athletes of all ages. Currently, there is evidence to suggest that participation in collision sports is implicated in premature degeneration of the cervical spine. There is some evidence to suggest that the same is true with noncollision sports and activities that result in direct and indirect repetitive loads to the cervical spine over time. The risk factors have yet to be clearly identified. The natural history and sequelae of premature degeneration have yet to be elucidated. Cervical spondylosis also appears to increase the severity, but not the frequency, of irreversible neurologic injury during collision sport participation. Prudence dictates that we not ignore the present evidence suggesting a link between neuropraxia and cervical stenosis. Proper screening for cervical stenosis in patients with transient neuropraxia with subsequent cessation of participation in collision sports if severe stenosis is present is suggested. There is no consensus for RTP guidelines in the setting of transient neurologic injuries in the athlete when severe degeneration is present, and each case must be considered individually with regard to the sport involved.  相似文献   
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Glomangiomas are characterized by cavernous vascular channels surrounded by glomus cells. Multiple glomangiomas, although usually painless, can be a few centimetres in size and appear as blue phlebectatic lesions. Surgical excision of multiple glomangiomas can lead to scarring and recurrences. Laser treatment using vascular lasers and CO2 lasers has been useful in small, superficial lesions. We present the successful sclerotherapy treatment of multiple glomangiomas using sodium tetradecyl sulphate in a 59-year-old man who presented with postoperative recurrence of multiple lesions.  相似文献   
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OBJECTIVES: Beta-thalassaemia minor (BTM) alone does not lead to iron overload, however, some gene modifiers and acquired causes are reported. When it is inherited together with a mutation in the HFE (HLA-H) gene associated with hereditary haemochromatosis, iron overload may ensue. To analyse the relationship between iron status and HFE mutations in Iranian BTM patients, we compared the frequency of the C282Y and H63D HFE mutations and ferritin level in a group of BTM patients from the National Thalassaemia Transfusion and Care Centre with that of healthy individuals. PATIENTS AND METHODS: Ninety-three (56 females) documented BTM cases and 104 (54 females) controls were enrolled in the study. Serum ferritin level was measured in all subjects by immuno-radiometric assay and HFE genotypes were determined using restriction fragment length polymorphism analysis of PCR-amplified HFE gene fragment. RESULTS: Eighteen (19.4%) BTM patients vs. 12 (11.5%) controls were H63D heterozygotes, while there were three (3.2%) cases and three (2.9%) controls with H63D homozygosity. All three C282Y mutations were found in BMT patients with one of them being a compound heterozygote. A significant difference was observed in the total number of HFE mutations in favour of BTM patients over the controls (P < 0.05, OR = 2.064). The H63D and C282Y allele frequencies were 12.9 and 1.61 in patients and 8.65 and 0 in controls, respectively. The mean ferritin level in cases with HFE mutations showed no significant difference from that of the patients without mutations (P > 0.05). CONCLUSIONS: Our results suggest that HFE mutations C282Y and H63D are more frequent in Iranian BTM patients than in the normal population, causing no significant changes in serum ferritin level.  相似文献   
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Background and Aim: Host genetic and environmental factors are viewed as a common basis of the different outcomes of hepatitis B virus (HBV) infection. Human leukocyte antigen (HLA) plays an important role in immunological reaction to HBV infection. In this study, we aimed to determine the association between HBV infection and HLA‐A, B, and DRB1 alleles in northern Iran. Methods: HLA‐A, B, and DRB1 alleles in 33 patients with chronic hepatitis B (CHB) and 31 healthy carriers as the persistent group, and 30 subjects who had spontaneously recovered from HBV infection were analyzed by using the polymerase chain reaction (PCR)–sequence‐specific primer (PCR‐SSP) technique. Results: The frequency of the HLA‐A*33 allele was higher in the persistent group than in the recovered group (10.16% vs 0%, P < 0.008); the frequency of the DRB1*13 allele was lower in the persistent group than in the recovered group (3.13% vs 11.67%, P < 0.03). The frequency of the B*52 allele was higher in CHB patients than healthy carriers (7.58% vs 0%, P < 0.05). The logistic regression model showed that the presence of the HLA‐DRB1*13 allele was the significant factor associated with protection against the persistency of HBV. There were significant differences between the HBV recovered group, CHB patients, and healthy carriers regarding age, hepatitis B e antigen, and anti‐hepatitis B e positivity. Conclusion: HLA‐A*33 was closely related with susceptibility to persisting hepatitis B infection, and HLA‐DRB1*13 was closely related with protection against persisting hepatitis B in an Iranian population. These findings emphasized that the host HLA polymorphism is an important factor in determining the outcome of HBV infection.  相似文献   
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BackgroundOccult hepatitis B virus (HBV) infection in blood donors is considered a potential threat for the safety of the blood supply, however conclusive studies on this issue are lacking. The aim of this study was to assess the occult HBV infection in blood donors with isolated hepatitis B core antibody (anti-HBc) living in the city of Arak, in the Central Province of Iran, as a low prevalence region for HBV.MethodsA total of 531 voluntary blood donors in Arak, Iran were included in this study. Hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), anti-HBc, and hepatitis C antibody (anti-HCV) were tested in all subjects. The presence of HBV-DNA was determined quantitatively in plasma samples of cases with isolated anti-HBc (HBsAg-negative, anti-HBs-negative, and anti-HBc-positive) by real-time PCR using the artus HBV RG PCR kit on the Rotor-Gene 3000 real-time thermal cycler.ResultsOf 531 subjects enrolled in this study, 11 (2.1%, 95% confidence interval 0.8–3.2%) had isolated anti-HBc. HBV-DNA was not detected in any of the cases with isolated anti-HBc.ConclusionsOur study showed that all the blood donors with isolated anti-HBc were negative for HBV-DNA, and occult HBV infection did not occur in the blood donors of this low prevalence region for HBV infection.  相似文献   
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