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51.
This study examined the effects of cochlear hearing loss on the ability to discriminate increments in the duration of a stimulus under conditions where the frequency and/or amplitude of the stimulus change dynamically. Three stimulus types were used: pure tones, frequency-modulated tones, and narrow bands of noise. The carrier/center frequency of each 250-ms stimulus either remained constant at 1035 Hz or varied randomly from presentation to presentation across the frequency range 432-2804 Hz. Two groups of listeners participated: 9 with bilateral cochlear hearing loss and 7 with normal hearing sensitivity. The results showed no differences in performance between the 2 groups. However, both groups showed poorer duration discrimination for the conditions where the carrier/center frequency changed randomly than for the conditions where the carrier/center frequency remained constant. In addition, performance was poorer for the narrowband noise stimuli than for the tonal stimuli. This pattern of results suggests that across-frequency temporal judgments are more difficult than isofrequency temporal judgments, but that cochlear hearing loss does not exacerbate this difficulty per se.  相似文献   
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We have developed a Potato virus X (PVX)-based vector system compatible with the GoldenBraid 2.0 (GB) cloning strategy to transiently express heterologous proteins or peptides in plants for biotechnological purposes. This vector system consists of three domestication vectors carrying three GB parts—the cauliflower mosaic virus (CaMV) 35S promoter with PVX upstream of the second subgenomic promoter of the PVX coat protein (PVX CP SGP), nopaline synthase (NOS) terminator with PVX downstream of the first PVX CP SGP and the gene of interest (GOI). The full-length PVX clone carrying the sequence encoding a green fluorescent protein (GFP) as GOI was incorporated into the binary GB vector in a one-step reaction of three GB parts using the four-nucleotide GB standard syntax. We investigated whether the obtained vector named GFP/pGBX enables systemic PVX infection and expression of GFP in Nicotiana benthamiana plants. We show that this GB-compatible vector system can be used for simple and efficient assembly of PVX-based expression constructs and that it meets the current need for interchange of standard biological parts used in different expression systems.  相似文献   
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In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis.  相似文献   
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This prospective study evaluated the efficacy of transvaginal ultrasonography combined with water-contrast in the rectum (RWC-TVS) in the diagnosis of rectal infiltration in 35 women with rectovaginal endometriosis; ultrasonographic findings were compared with surgery and histology. The sensitivity of RWC-TVS in identifying rectal infiltration reaching at least the muscular layer was 100%, the specificity was 85.7%, the positive predictive value was 91.3%, and the negative predictive value was 100%. In 4 of 5 (80.0%) nodules reaching the submucosa, the depth of infiltration was underestimated by RWC-TVS. The RWC-TVS reliably determined the largest diameter of the endometriotic nodules and was well tolerated by the patients.  相似文献   
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OBJECTIVE: There is an increasing evidence that genetic factors play a role in the etiology of malignant tumors. Mutations of BRCA1 and BRCA2 genes are responsible for an increased risk of ovarian cancer. The role of mutations in NOD2 gene in this type of neoplasm is still under investigation. THE AIM: The aim of this study was to determine: 1. incidence of NOD 2 3020insC constitutional mutation in a group of consecutive women with ovarian cancer, 2. risk of developing ovarian cancer in patients with NOD2 gene mutation, 3. clinical and pathological features of ovarian cancer in NOD2 gene mutation carriers. PATIENTS AND METHODS: Clinical and pathological data were collected from 257 non-selected patients with primary epithelial ovarian cancer. The researches identified NOD2 3020insC gene mutation. On the basis of patient source documentation we obtained the data concerning the age of patients at diagnosis, histopathological recognition, FIGO stage and morphological grade G. RESULTS: 19 out of 257 women were identified with germ-line 3020insC mutation of NOD2 gene (7.39%). An increased risk of ovarian cancer in NOD2 mutation carriers was not revealed (OR=1.01; p=0.928; 95% Cl=0.61-1.66). The mean age at diagnosis of patients with NOD2 mutation was 54.8 (SD=9.9), while for non-carriers it was 53.2 (SD=10.2). The difference between these frequencies was statistically irrelevant (p=0.550). Clinical and pathological profile of ovarian cancer was made. We assessed the following features: age at disease onset, histopathology, FIGO stage and morphological grade G. For NOD2 mutation carriers no statistically significant features of ovarian cancer were revealed. CONCLUSION: 1. Despite high frequency of constitutional mutations occurrence in NOD2 gene in women with ovarian cancer, genetic testing seem not to be justified in all women diagnosed with this disease. 2. Due to a lack of increased risk of ovarian cancer in NOD2 gene mutation carriers, proceedings for them may not differ from recommendations for general population. 3. It is difficult to determine characteristic clinical and pathological features of ovarian cancer for NOD2 gene mutation carriers.  相似文献   
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