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991.
Background: Progressive movement limitation in patients with Duchenne's muscular dystrophy (DMD) may mask the onset of cardiac involvement. We aimed to determine whether myocardial performance index (MPI), either by conventional Doppler (CD) or tissue Doppler imaging (TDI), could detect subclinical myocardial dysfunction in DMD patients. Furthermore, we assessed the atrial ejection force (AEF) to evaluate possible existence of latent diastolic dysfunction. Method: Twenty DMD patients without signs and symptoms of cardiac impairment and 20 age matched control group enrolled into the study. MPI for right ventricle and left ventricle (LV) was assessed with CD and TDI for comparison. Results: No significant difference was detected in ejection fraction, fractional shortening, and AEF between two groups. CD derived MPI was higher for both ventricles in the patients (P < 0.0001). Moreover, the TDI derived MPI were significantly higher in the patients in mitral, tricuspid, and septal views (P < 0.0001). A significant decrease of mitral myocardial systolic wave velocity was detected in the patients, in favor of early involvement of the posterobasal LV myocardium. All acceleration and deceleration times’ values for the late mitral inflow were higher whereas the rates were significantly lower in the patients. There was no significant difference between AEF of both groups. Conclusion: MPI might be a useful parameter for early detection of occult cardiac dysfunction in DMD patients when other simple and standard echocardiographic parameters are within the normal limits. Lack of atrial contribution in LV filling due to atrial contractile dysfunction may play a role in DMD cardiac dysfunction. (Echocardiography 2011;28:1088‐1094)  相似文献   
992.
In this cross-sectional study we used magnetic resonance imaging (MRI)-based voxel based morphometry (VBM) in a sample of HIV positive patients to detect structural gray and white matter changes. Forty-eight HIV positive subjects with (n = 28) or without (n = 20) cognitive deficits (mean age 48.5 ± 9.6 years) and 48 age- and sex-matched HIV negative controls underwent MRI for VBM analyses. Clinical testing in HIV patients included the HIV dementia scale (HDS), Unified Parkinson’s Disease Rating Scale (UPDRS) and the grooved pegboard test. Comparing controls with HIV positive patients with cognitive dysfunction (n = 28) VBM showed gray matter decrease in the anterior cingulate and temporal cortices along with white matter reduction in the midbrain region. These changes were more prominent with increasing cognitive decline, when assigning HIV patients to three cognitive groups (not impaired, mildly impaired, overtly impaired) based on performance in the HIV dementia scale. Regression analysis including all HIV positive patients with available data revealed that prefrontal gray matter atrophy in HIV was associated with longer disease duration (n = 48), while motor dysfunction (n = 48) was associated with basal ganglia gray matter atrophy. Lower CD4 cell count (n = 47) correlated with decrease of occipital gray matter. Our results provide evidence for atrophy of nigro-striatal and fronto-striatal circuits in HIV. This pattern of atrophy is consistent with motor dysfunction and dysexecutive syndrome found in HIV patients with HIV-associated neurocognitive disorder.  相似文献   
993.

Background and Aims

The duration of the protection of hepatitis B vaccination for infants and the necessity of a booster dose administration is unknown. The aim of the present study was to evaluate the persistence of seroprotection after hepatitis B virus (HBV) vaccination in order to determine the necessity of a single booster dose in 5- to 7-year-old children.

Methods

This clinical trial study was conducted from 2004 to 2005.The study population included all children aged 5 to 7 years old in the Kohgiloyeh and Boyerahmad province who had been vaccinated starting at birth with hepatitis B vaccine. Among these children, 729 were selected via a multiple-stage sampling method. Parents gave their informed consent, and blood specimens (3 ml) were obtained from children. Hepatitis B surface antibody (HBsAb) and hepatitis B surface antigen (HBsAg) were determined by enzyme-linked immunosorbent assay (ELISA). Subjects with nonprotective titer levels (< 10 mIU/ml) received a booster does of the DNA recombinant vaccine. Four weeks after the administration of a booster dose, the antibody to HBsAg (anti-HBs) titer was measured. Data were analyzed using SPSS software, and analyses included chi-square, ANOVA, and independent-samples and paired-samples t-tests.

Results

615 children (84.4%) had a protective antibody titer. The mean antibody titer was 230.5 ± 308.9 IU/ml, with a range of 10.6 to 1175 IU/ml. 15.6% of subjects had a nonprotective antibody titer, and the mean antibody titer was 4.97 ± 3.5 IU/ml. All subjects were HBsAg negative. No statistically significant differences were found by sex or by urban versus rural area of residence. The seroprotection rates significantly decreased by as the age of the children increased.Following the booster dose, 78.1 % of the children had a protective titer, and the mean titer significantly increased from 4.97 ± 3.5 at birth to 332.1 ± 402 IU/ml after the booster (P < 0.001).

Conclusions

According to our results, the proper response of the immune system to a booster dose of HBV at 5 to 7 years of age reveals that immunologic memory is good after primary vaccination. Administration of booster dose does not appear to be necessary at these ages even though these children have a greater possibility of exposure to HBV in school age.  相似文献   
994.
Deletion 13q14 on fluorescence in situ hybridization (FISH) analysis is the most common cytogenetic abnormality in chronic lymphocytic leukaemia (CLL), and is a favourable prognostic biomarker when detected as a sole abnormality. We intensively interrogated clinical outcome in 323 consecutive, untreated CLL patients with isolated 13q‐ identified within 2 years of diagnosis. We also analyzed outcome in 217 additional patients with deletion 11q22.3 or 17p13.1, or trisomy 12, based on whether these occurred in isolation or in conjunction with 13q‐. Patients with a heterozygous 13q‐ and those with a homozygous deletion had similar time to first treatment (TFT) and overall survival (OS). In contrast, a higher percentage of 13q‐ nuclei was associated with significantly shorter TFT (P < 0·001). The 5‐year untreated rate was 79% for patients with isolated 13q‐ in ≤65·5% of nuclei compared to 38% among those with 13q‐ in >65·5% of nuclei (P < 0·001). The percentage of nuclei exhibiting 13q‐ remained an independent predictor of TFT after controlling for ZAP‐70, IGHV, or CD38 (all P < 0·001). Among patients with 13q‐ plus one other FISH abnormality, concomitant 13q‐ appeared to attenuate the shorter survival associated with 17p‐ (P = 0·019). The clinical implications of 13q‐ in CLL appear more complex than originally appreciated.  相似文献   
995.
996.
997.

Introduction

The search for alternative training environments in dentistry responded mainly to scarcity and lack of standardisation of training material and non-availability of specific clinical procedures. The development of haptic virtual reality (VR) dental trainers provides a platform where irreversible procedures can be safely and unlimitedly practised. The aim of this study was to assess the educational implementation of these devices and evaluate schools' satisfaction.

Methods

Dental schools that were using haptic VR dental trainers, were approached. The Dental Trainer User Inventory (DTUI), addressing the educational implementation and users' satisfaction, was developed and distributed.

Results

Twenty-seven schools completed the DTUI. The total number of VR dental trainers available varied from one to 42 devices with a mean of 7 devices. The dental trainer was mostly made available from the first year (63.0%) of the undergraduate program, but it was mostly integrated into the curriculum by the third year (70.4%). Curricular integration was reported by 18 schools (66.7%), while nine schools (33.3%) indicated that they had not yet achieved integration. Twenty-one schools (69.4%) were ‘satisfied’ or ‘very satisfied’ with the devices, while two schools (7.4%) were dissatisfied and six schools (22.2%) were neither satisfied nor dissatisfied.

Conclusion

VR haptic dental trainers are implemented in multiple dental programs and are also being used for educational research and clinical training. Even though curricular changes and teachers' acceptance remain a challenge, most schools are satisfied with VR haptic dental trainers and would recommend the device to other schools.  相似文献   
998.
Zamani A  Omrani GR  Nasab MM 《BONE》2009,44(2):331-334
Lithium salts are widely used in treating psychiatric patients. Lithium may be associated with hyperparathyroidism, a risk factor for osteoporosis. However, the data on the effect of lithium on bone mass are conflicting. We assessed bone mineral density with dual-energy X-ray absorptiometry at the hip and lumbar spine in 75 lithium treated outpatients and 75 normal subjects matched for age, sex and body mass index. Serum total calcium, intact parathyroid hormone (PTH), estradiol, osteocalcin, total alkaline phosphatase (ALP) and C-telopeptide (CTX) in addition to fasting urinary calcium excretion were also determined in both groups. The mean (+/-SD) bone density in lithium treated patients was 4.5% higher at the spine (P<0.05), 5.3% higher at the femoral neck (P<0.05) and 7.5% higher at the trochanter (P<0.05). In addition, lithium treated patients had lower serum total ALP (P<0.005), lower serum osteocalcin (P<0.005) and lower serum CTX (P<0.05) but the total calcium, PTH and urinary calcium excretion did not differ significantly between patients and controls. In conclusion, our results suggest that maintenance therapy with lithium carbonate may preserve or enhance bone mass. These data also suggest a lower bone turnover state in those receiving lithium.  相似文献   
999.
The publication of new standards for terminology and labeling marks an important step in ensuring consistency and traceability of cellular therapies at the global level. However, it is only with the widespread implementation of the standard that the benefits can be truly realized. This paper provides guidance on the practical aspects of adopting these new standards for organizations with differing current levels of computerization. It discusses project management, equipment, licensing, and validation topics.  相似文献   
1000.
The International Cellular Therapy Coding and Labeling Advisory Group was established to address the growing need for standardization of terminology and labeling for cellular therapy products as a result of increasing international transfer of these products. This paper presents new standards for terminology and labeling. These standards have been developed through a consultative process and are supported by key professional and accreditation bodies. By using these standards, together with the unique donation identification numbers and international product reference tables provided by the International Society of Blood Transfusion (ISBT) 128 Standard, consistency and traceability can be assured at the global level. A companion paper provides guidance on the implementation of the ISBT 128 system.  相似文献   
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