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61.
62.

Background

This prospective study attempts to study the clinico-radiological differences between patients with syndromic AAD (SAAD), non-syndromic AAD (NSAAD), and AAD with Klippel–Feil anomaly (AADKFA) that may impact management.

Methods

In 46 patients with AAD [SAAD (including Morquio, Down, Larson and Marshall syndrome and achondroplasia; n?=?6); NSAAD(n?=?20); and, AADKFS (n?=?20)], myelopathy was graded as mild (n?=?17, 37 %), moderate (15, 32.5 %) or severe (14, 30.5 %) based on Japanese Orthopaedic Association Score modified for Indian patients (mJOAS). Basilar invagination (BI), basal angle, odontoid hypoplasia, facet-joint angle, effective canal diameter, Ishihara curvature index, and angle of retroversion of odontoid and vertebral artery (VA) variations were also studied.

Statistics

Clinico-radiological differences were assessed by Fisher’s exact test, and mean craniometric values by Kruskal–Wallis test (p value ≤?0.05 significant)

Results

Incidence of irreducible AAD in SAAD (n?=?0), NSA AD (11.55 %) and AADKFS (n?=?18.90 %) showed significant difference (p?=?0.01). High incidence of kyphoscoliosis (83 %) and odontoid hypoplasia (83 %) in SAAD, and assimilated atlas and BI in NSAAD and AADKFA groups were found. In AADKFA, effective canal diameter was significantly reduced(p?=?0.017) with increased Ishihara index and increased angle of odontoid retroversion; 61 % patients had VA variations. Thirty-five patients underwent single-stage transoral decompression with posterior fusion (for irreducible AAD) or direct posterior stabilization (for reducible AAD). Postoperative mJOAS evaluation often revealed persistent residual myelopathy despite clinical improvement.

Conclusions

Myelopathy is induced by recurrent cord trauma due to reducible AAD in SAAD, and compromised cervicomedullary canal diameter in NSAAD and AADKFA. SAAD in children may be missed due to incomplete odontoid ossification or coexisting angular deformities. In AADKFA, decisions regarding vertebral levels to be included in posterior stabilization should take into consideration intact intervening motion segments and compensatory cervical hyperlordosis. Following VA injury, endovascular primary vessel occlusion/stenting across pseudoaneurysm preempts delayed rehemorrhage.  相似文献   
63.
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65.
The majority of Korean human immunodeficiency virus type 1 (HIV-1) isolates are composed of the Korean clade B strain that is distinct from the subtype B prevalent in North America and Europe. However, it is still not clear how HIV-1 was introduced, transmitted, and evolved within the Korean population. To identify the evolutionary characteristics of Korean HIV-1, we estimate the molecular epidemic history of HIV-1 subtype B gp120 env in Korea in comparison with sequences isolated from other geographic locations. A Bayesian Markov chain Monte Carlo (MCMC) statistical inference was used to estimate the time of divergence of subtype B. The estimated time of divergence of subtype B and the distinct monophyletic Korean B cluster was estimated to be in the early and mid-1960s, respectively. Substitution rates were estimated at 7.3×10(-3) and 8.0×10(-3) substitutions per site per year for HIV-1 subtype B and Korean clade B, respectively. The demographic dynamics of two Korean data sets showed that the effective number of infections in Korea increased rapidly until the early 1980s, and then the rate only slowly increased until the mid-1990s when the population growth approached a steady-state. These results suggest that the growth rate of prevalent HIV-1 strains in Korea was lower than in other countries, suggesting that the evolution of HIV-1 Korean clade B was relatively slow. Furthermore, the limited transmission of HIV-1 within the Korean population likely led to the independent evolution of this virus to form the HIV-1 Korean clade B.  相似文献   
66.

BACKGROUND:

Bronchodilator responses (BDR) are routinely used in the diagnosis and management of asthma; however, their acceptability and repeatability have not been evaluated using quality control criteria for preschool children.

OBJECTIVES:

To compare conventional spirometry with an impulse oscillometry system (IOS) in healthy and asthmatic preschool children.

METHODS:

Data from 30 asthmatic children and 29 controls (two to six years of age) who underwent IOS and spirometry before and after salbutamol administration were analyzed.

RESULTS:

Stable asthmatic subjects significantly differed versus controls in their spirometry-assessed BDR (forced expiratory volume in 1 s [FEV1], forced vital capacity and forced expiratory flow at 25% to 75% of forced vital capacity) as well as their IOS-assessed BDR (respiratory resistance at 5 Hz [Rrs5], respiratory reactance at 5 Hz and area under the reactance curve). However, comparisons based on the area under the ROC curve for ΔFEV1 % initial versus ΔRrs5 % initial were 0.82 (95% CI 0.71 to 0.93) and 0.75 (95% CI 0.62 to 0.87), respectively. Moreover, the sensitivity and specificity for ΔFEV1 ≥9% were 0.53 and 0.93, respectively. Importantly, sensitivity increased to 0.63 when either ΔFEV1 ≥9% or ΔRrs5 ≥29% was considered as an additional criterion for the diagnosis of asthma.

CONCLUSION:

The accuracy of asthma diagnosis in preschool children may be increased by combining spirometry with IOS when measuring BDR.  相似文献   
67.
68.

Objective

The psychobiological model of temperament and character indicates that personality traits are heritable and, during development, constantly influence one’s susceptibility to schizophrenia. Our objective was to evaluate temperament and character in subjects at ultra-high risk (UHR) for psychosis and individuals with first-episode schizophrenia.

Methods

UHR for psychosis subjects (n = 50), first-episode schizophrenia patients (n = 33), and normal controls (n = 120) were compared on temperament and character dimensions, and correlation analysis of each personality dimension with psychopathologies, global and social functioning, and self-esteem. General and social self-efficacy reports were conducted. UHR subjects were followed-up for 24 months and the baseline personality dimensions were compared between the converted and non-converted groups.

Results

Both clinical groups showed abnormal personality traits in terms of temperament (higher harm avoidance, lower reward dependence and persistence) and character (lower self-directedness and cooperativeness). Psychosocial functioning and psychological health components were found to be correlated with some personality dimensions. The conversion rate of overt psychotic disorder was 25.0% at the 24-month follow-up. Baseline cooperativeness dimension was a significant predictive dimension for conversion into overt psychosis in the UHR group during the follow-up period.

Conclusion

Patients with first episode schizophrenia have a pervasively altered personality profile from normal controls. More importantly, this altered personality profile already emerged in putative prodromal, UHR individuals. The present findings indicate that certain personality traits can play a protective or vulnerable role in developing schizophrenia.  相似文献   
69.
Introduction: In 2004, a Cochrane Review and AAN practice parameter concluded that prednisone 0.75 mg/kg/day is of short‐term efficacy in Duchenne muscular dystrophy (DMD). Subsequent efforts to standardize care for DMD indicated wide variation in corticosteroid use. Methods: We surveyed physicians who follow patients with DMD, including: (1) clinics in the TREAT‐NMD (Translational Research in Europe—Assessment and Treatment of Neuromuscular Diseases) network (predominantly Europe) and (2) U.S. MDA clinic directors. We also documented the co‐administered corticosteroids in a trial of a putative treatment (ataluren) for DMD. Results: Of 105 Treat‐NMD clinicians, corticosteroids were not used in 10 clinics, and 29 different regimens were used—the most frequent 0.75 mg/kg/day prednisone (61 centers); 10 days on/10 days off (36 centers); 0.9 mg/kg/day deflazacort (32 centers); and 5 mg/kg/day on weekends (10 centers). Similar diversity was identified in MDA clinics and in the ataluren trial. Conclusions: Variability in corticosteroid use suggests uncertainty about risks/benefits of corticosteroid regimens for DMD. Muscle Nerve, 2013  相似文献   
70.
Although several studies have detected differences in clinical features among specific phobias, there is a shortage of detailed national data on the on the DSM-IV SP subtypes, particularly in the Asian population. To examine the prevalence, demographic and other correlates, and co-morbidities of DSM-IV SP subtypes in a nationwide sample of Korean adults. We recruited 6510 participants aged 18–64 years for this study. Lay interviewers used the Composite International Diagnostic Interview to assess participants. We analyzed socio-demographics, health-related correlates and frequencies of comorbid mental disorders among participants with SP and each subtypes compared to unaffected adults. The prevalence of lifetime DSM-IV SP was 3.8%, and animal phobias were the most prevalent type of SP. Blood–injection–injury phobia was negatively associated with education, whereas situational phobia was positively associated with education. The strongest mental disorder comorbidity was associated with situational phobia; there is a higher probability of comorbid mood (OR=5.73, 95% CI=2.09–15.73), anxiety (OR=7.54, 95% CI=2.34–24.28), and somatoform disorders (OR=7.61, 95% CI=1.64–35.22) with this subtype. Blood–injection–injury phobia was highly associated with alcohol dependence (OR=9.02, 95% CI=3.54–23.02). Specific phobias are heterogeneous with respect to socio-demographic characteristics and comorbidity pattern. Implications of the usefulness of current subtype categories should continue to be investigated.  相似文献   
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