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61.
Serap A, Funda O, Bengu K, Mehmet K, Nazan C, Rasit Y, Savas K. Sustained seroconversion of chronic hepatitis B infection after stem cell transplantation.
Pediatr Transplantation 2011: 15: E92–E95. © 2010 John Wiley & Sons A/S. Abstract: We present an 18‐yr‐old adolescent with acute lymphocytic leukemia, who underwent peripheral blood SCT with serologically and histologically documented chronic hepatitis B infection. Prior and during the transplant process, lamivudine was administered orally and he underwent SCT with a twofold decrease in viral load at the time of transplant from his HLA full matched, HBV natural immune (anti‐HBs and anti‐HBc positive) donor. Successful engraftment was achieved and three months after SCT, HBV seroconversion was documented accompanied with an ALT flare. Chronic graft‐versus‐host disease coincided after the transplantation, and he has been on immunosuppressive treatment for 25 months with sustained HBV seroconversion. We assume that adoptive immunity transfer combined with antiviral treatment might also constitute sustained seroconversion in chronic HBV, besides the reported risk of reactivation.  相似文献   
62.
Song T  Bandos AI  Rockette HE  Gur D 《Medical physics》2008,35(4):1547-1558
The task of searching and detecting multiple abnormalities depicted on an image, or a series of images, is a common problem in different areas such as military target detection or diagnostic medical imaging. A free response receiver operating characteristic (FROC) approach for assessing performance in many of these scenarios entails marking the locations of suspected abnormalities and indicating a level of suspicion at each of the marked locations. One of the important characteristics of a system being evaluated under the FROC paradigm is its performance in the conventional ROC domain, namely classifying a subject (or a unit of interest) as "negative" or "positive" in regard to the presence of the abnormality (or any of the abnormalities) of interest. With FROC data we can compare subjects by specifying a function of multiple scores within a subject. This approach allows formulating subject-based ROC type indices that can be estimated using existing ROC concepts. In this article we focus on indices that reflect the ability of the system to discriminate between actually negative and actually positive subjects. We consider a previously proposed index that is based on the comparison of the highest scores on subjects and two new indices that are based on potentially more stable comparison functions, namely comparison of average scores and stochastic dominance. Based on these indices we develop nonparametric procedures for comparing subject-based discriminative ability of diagnostic systems being evaluated under the FROC paradigm. We also investigate the properties of the statistical procedures in a simulation study.  相似文献   
63.
Oner S  Ercan F  Arbak S 《Acta histochemica》2004,106(3):207-217
Small bowel is one of the organs that can in principle be transplanted. Optimum preservation of the organ is essential for the success of transplantation. The aim of the present study is the investigation of time-related morphological changes of rat small bowel during preservation in hypothermic Euro-Collins (EC) and Ringer's lactate (RL) solution using light microscopy and transmission electron microscopy to evaluate the integrity of intercellular complexes of mucosal epithelium, one of the tissues of the intestine that is most susceptible to ischemia. Small bowels were perfused with either EC, RL solution or physiological saline solution and were placed in the different preservation solutions at 4 degrees C for 0, 3, 6 and 12 h. The results of our study suggest that both preservation solutions are suitable for short-term preservation of the small bowel although RL solution is more effective than EC solution. However, we conclude that further improvement of preservation solutions and/or techniques are needed to perform long-term preservation.  相似文献   
64.
It has been shown that BRAF(V600E) mutation in papillary thyroid carcinomas (PTC) is associated both with pathogenesis and poor prognosis. In this study, we aimed to investigate the relationship of the BRAF(V600E) mutation and the established prognostic factors in a cohort of Turkish patients with PTC. Forty-six cases of papillary thyroid carcinoma have been evaluated for the presence of BRAF(V600E) mutation. BRAF(V600E) has been examined by restriction fragment length polymorphism. BRAF(V600E) mutation status has been compared with well-known histopathological and clinical prognostic parameters such as invasion of thyroid capsule, extrathyroidal extension, and the presence of lymph node and/or distant metastasis. We have found that BRAF(V600E) mutation was present in the majority of our cases (40/46). Considering the stage of the disease, five of the negative cases were in stage 1 while the remaining one was in stage 2. Only one BRAF(V600E) negative case has shown extrathyroidal extension and lymph node metastasis. All four patients with distant metastasis had BRAF(V600E) mutation. Statistical analyses revealed that there are no significant relationship between the BRAF(V600E) mutation and the established prognostic factors. We found a relatively higher BRAF(V600E) mutation rate in classical type PTC than in other similar studies. We think that the limited number of our cases may either weaken or mask some potentially important relationship between BRAF(V600E) mutation and the established prognostic factors.  相似文献   
65.
The catechol-O-methyltransferase (COMT) val158met polymorphism has received attention in schizophrenia due to its role in prefrontal dopamine catabolism. Given the rich dopaminergic innervations of the olfactory bulb and the influence of dopamine on the transmission of olfactory signals, the authors examined the influence of COMT genotype status on the olfactory processing impairment observed in schizophrenia. The University of Pennsylvania Smell Identification Test was administered unirhinally to individuals with schizophrenia (n = 42) and a demographically matched sample of healthy controls (n = 30). Individuals were genotyped for the COMT val158met polymorphism. A statistically significant interaction of diagnosis and COMT genotype was observed, such that schizophrenia heterozygotes and Met homozygotes showed impaired odor identification accuracy relative to Val158 homozygotes. These findings could not be explained by factors such as antipsychotic medication status, clinical symptomatology, or demographic and illness characteristics. Notably, the schizophrenia Val158 homozygotes' odor identification performance was comparable to that of the control group. These data indicate that odor identification impairments observed in schizophrenia are influenced by the COMT val158met polymorphism. This relationship is consistent with specific dopaminergic modulation of primary olfactory sensory afferents, rather than a broader effect on cognitive processes. Future studies that examine the olfactory processing deficit in schizophrenia with respect to other olfactory measures and COMT haplotypes is warranted.  相似文献   
66.
67.
Tsetse flies (Diptera: Glossinidae: Glossina spp.) are vectors for African trypanosomiasis, a devastating disease that kills both people and animals in sub-Saharan Africa. Trypanosomes ingested with an infected bloodmeal reside within the gut of tsetse and eventually move to the salivary glands where they become transmissible during blood feeding. Although tsetses are efficient vectors for disease transmission, infection prevalence in the field is surprisingly low, a trait referred to as refractoriness. Refractoriness is relatively more pronounced in palpalis subgroup flies, although certain species within the susceptible morsitans species complex are also highly refractory, such as Glossina pallidipes Austen. We examined the role of the humoral immune response in refractoriness to infection by comparing the expression of the antimicrobial peptide gene attacin across three species with varied vector competence. Gene expression was measured both temporally (time after feeding and fly age) and spatially (tissue specificity). Although microbial immune challenge induces attacin expression in all three species, "refractory" fly species showed an uninduced, baseline level of systemic (fat body) attacin, whereas the "susceptible" flies did not. In addition, refractory species had a higher level of attacin expression in the proventriculus and midgut. We also found that blood feeding alone up-regulated attacin expression in refractory species but not in the susceptible species. Finally, reverse genetics showed that repression of attacin by double-stranded RNA-mediated RNA interference increased susceptibility to trypanosome infection in G. pallidipes. The role of early, uninduced attacin expression, and its role in relative refractoriness in tsetse, is discussed.  相似文献   
68.
Background/aim The aim of the study was to carry out the cultural adaptation and translation of the ICU mobility scale (IMS) into Turkish and research the psychometric properties.Materials and methods This study was based on methodological design. The IMS was translated from English to the Turkish through a regularised translation process. Two physiotherapists assessed patients independently in the coronary intensive care unit. The measures such as construct validity, intra and interrater reliability, and internal consistency of the IMS Turkish version were assessed. Results A total of 70 intensive care patients were included in the study. The intrarater and interrater reliability of the IMS was excellent. The weighted Kappa value was 0.92 (0.87–0.96) for the intrarater reliability, and 0.87 (0.80–0.93) for the interrater reliability. There were significant correlations between the IMS and functional status score for the intensive care unit (r = 0.83), Perme intensive care unit mobility score (r = 0.84), Katz activities of daily living (r = 0.73), handgrip strength (r = 0.62), knee extension strength (r = 0.46), and age (r = –0.44).Conclusion This study suggests that the IMS Turkish version is a reliable and valid scale for assessing functional status and mobility level in ICU patients.  相似文献   
69.
Reactive nitrogen species may play a mechanistic role in neurodegenerative diseases by posttranslationally altering normal brain proteins. In support of this hypothesis, we demonstrate that an anti-3-nitrotyrosine polyclonal antibody stains all of the major hallmark lesions of synucleinopathies including Lewy bodies, Lewy neurites and neuraxonal spheroids in dementia with Lewy bodies, the Lewy body variant of Alzheimer's disease, and neurodegeneration with brain iron accumulation type 1, as well as glial and neuronal cytoplasmic inclusions in multiple system atrophy. This antibody predominantly recognized nitrated alpha-synuclein when compared to other in vitro nitrated constituents of these pathological lesions, such as neurofilament subunits and microtubules. Collectively, these findings imply that alpha-synuclein is nitrated in pathological lesions. The widespread presence of nitrated alpha-synuclein in diverse intracellular inclusions suggests that oxidation/nitration is involved in the onset and/or progression of neurodegenerative diseases.  相似文献   
70.
Gynaecomastia in adolescents is a benign glandular proliferation of the male breast. Secondary causes of gynaecomastia in adolescents are relatively rare and may result from a wide variety of rare pathological conditions. Among these, klinefelter syndrome, complete androgen resistance, adrenal tumours and oestrogen-secreting testicular tumours, hypogonadism, hyperthyroidism, kidney disease and medications play a role in aetiology. The aim of our study is to review the demographic characteristics, hormone profile, aetiological characteristics of paediatric gynaecomastia patients admitted to a single center and to determine the frequency of pathological gynaecomastia. Forty-three male patients with gynaecomastia who applied to the paediatric endocrinology outpatient clinic were included in our study. Demographic characteristics, physical examination findings, hormone profile, breast ultrasonography and karyotype results of the patients were recorded. There were 43 male patients in our study. Thirty-six (83.7%) of the patients were pubertal gynaecomastia, 7 (16.2%) were pathological gynaecomastia. Three of the patients with pathological gynaecomastia were prepubertal gynaecomastia, 2 had klinefelter syndrome, 1 had hypergonadotropic hypogonadism after acute lymphoblastic leukaemia treatment and 1 had gynaecomastia after spirololactone use. Careful evaluation of patients with gynaecomastia is especially important in detecting pathological types. We reported the rare prepubertal gynaecomastia and klinefelter frequency in our study.  相似文献   
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