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131.
ObjectiveTo compare image quality of free-breathing T2-weighted MultiVane-XD (MVXD) sequence (non-Cartesian k-space filling using radial rectangular blades) with conventional MR sequences (short tau inversion recovery [STIR],balanced true field echo [BTFE], T1 in phase fast field echo [T1 FFE], and T1-fat saturated postgadolinium [T1PG]) in MR imaging of chest.Materials and MethodsTwenty-one patients (10 men and 11 women) underwent chest MRI including T2W MVXD, STIR, BTFE (18/21), T1 FFE, T1PG (10/21) sequences at 1.5 T. Two reviewers (A.S.B and M.J. with 20 and 10 years of experience in pulmonary imaging, respectively) evaluated each sequence with respect to overall image quality, image sharpness, definition of mediastinal vessels including the aorta, pulmonary arteries, superior vena cava, intrapulmonary vessels; trachea, main bronchi, intrapulmonary airways; lung-mediastinal interface, pulmonary lesion detection, and artefacts in the upper, middle, and lower third of chest using 5-point scales. No sedation was given. Pairwise comparisons between T2W MVXD and the 4 conventional sequences were made using unpaired student's t test.ResultsMean age of patients was 30.67 years (range: 6-60 years). T2 MVXD showed significantly better overall image quality and sharpness than STIR, T1 FFE, and T1PG (P < 0.01) while it was comparable to BTFE. Mediastinal vessels were significantly better visualized on T2 MVXD as compared to STIR and T1 (P < 0.003). However, BTFE and T1PG were superior to T2 MVXD for visualization of great vessels, SVC, and intrapulmonary vessels (P < 0.01). Visualization of trachea, major bronchi, intrapulmonary airways as well as intrapulmonary lesion detection was significantly better on T2 MVXD images in comparison to any of the other 4 sequences (P < 0.03). Intrapulmonary artifacts were significantly lesser in BTFE images as compared to T2 MVXD (P < 0.01). No significant difference was found between the severity of intrapulmonary artifacts in other MR sequences as compared to T2 MVXD.ConclusionsBy virtue of its better overall image quality, sharpness, superior visualization of mediastinal airways, and lesion detection, T2 MultiVane-XD promises to be a robust addition in the armamentarium of thoracic radiologists.  相似文献   
132.

Background

To study the efficacy of inside-out technique in completely eradicating the cholesteatoma from middle ear and mastoid, preservation of hearing & and quality of life post mastoidectomy with regards to recurrent discharge, wax, granulations.

Material and methods

Non-randomized, prospective, observational study performed at the Department of ENT in our hospital. In the study we included 100 patients presenting with chronic suppurative otitis media with cholesteatoma, they underwent inside out mastoidectomy and were followed up till the end of the study to evaluate the efficacy of inside out mastoidectomy in eradicating the disease from the middle ear cleft. To assess preservation of hearing and to assess cavity problems.

Results

Of the 100 patients, 98 patients had a total clearance of disease by the inside out approach, and 2 patients, had doubtful clearance. All patients came for regular follow up and none of them had residual disease at the end of the study period. Thus, the overall success rate was 100% in our study. A significant improvement in the mean air conduction (p?<?0.01) and the mean air bone gap (p?<?0.01) was seen in all postoperatively at 3rd month PTA. Only one patient had conductive hearing loss one and a half years postoperatively after initial improvement. A dry self-cleansing cavity was achieved in 95% of the patients and only 5% required regular cleaning of wax the cavities.

Conclusion

Inside out mastoidectomy is a better alternative in canal wall down procedures as it not only clears the disease from the middle ear cleft, but also leaves behind a small postoperative cavity, which will preserve the hearing, decrease the cavity problems and increase the quality of life of such patients.  相似文献   
133.
134.
18F-Fluorocholine (FCH) PET/CT is evolving as a functional imaging modality for the preoperative imaging of abnormal parathyroid tissue(s) helping to localize eutopic and ectopic parathyroid tissue and limit the extent of surgery. FCH PET/CT may show incidental uptake in various thyroid lesions necessitating further evaluation, whereas the role of 18F-fluorodeoxyglucose (FDG) PET/CT in the detection of incidental thyroid nodules is well documented. The case of a middle-aged woman with dual pathology of parathyroid adenoma and papillary thyroid cancer detected on FCH and FDG PET/CT is presented.  相似文献   
135.
136.
Background: Fibroblast growth factor receptors are growth factor receptor tyrosine kinases, exerting their roles in embryogenesis, tissue homeostasis, and development of cancer. However, little is known about the expression and function of FGFRL1 in esophageal cancer (EC). Methods: We systematically evaluated the expression of FGFRL1 in TCGA and GETex datasets followed by expression analysis in EC cell lines and clinical specimens using immunofluorescence (IF) and immunohistochemistry (IHC) respectively. Results: GEPIA analysis on TCGA and GETex datasets identified significant upregulation of FGFRL1 in EC patients (n=182) compared to normal controls (n=286, p<0.05). IHC analysis showed significantly higher FGFRL1 expression in EC tissues as compared to the distant matched non-malignant tissues (p<0.001).  Immunoflourescence in EC cells suggested increased expression of FGFRL1 from WDSCC (KYSE30) to MDSCC (KYSE140) and finally to PDSCC (KYSE410). In-silico tools predicted miR-107 as most significant miRNA regulating FGFRL1 expression. qRT-PCR revealed miR-107 expression to be significantly and inversely correlated with FGFRL1 expression in 73% (22/30) EC tissues (p=0.015) and over-expression of miR-107 resulted in significantly decreased expression of FGFRL1 at mRNA (fold change=0.11, p=0.0016) as well as protein level in miR-107 versus NC treated cells. Luciferase reporter assay using FGFRL1-3’UTR further confirmed it to be a direct target of miR-107. Conclusion: Our results herein document clinical as well as functional relevance of FGFRL1 in EC and its regulation by miR-107.  相似文献   
137.

Objective

To compare the physical growth outcomes, morbidity profile and mortality at an age of 12 months among late preterm (340/7 to 366/7) neonates to term (370/7 to 416/7) neonates.

Study design

Prospective cohort study.

Setting

A tertiary care center of Northern India during 2014-2015.

Participants

200 apparently healthy late preterms and term infants, followed up to 12 months of age.

Main outcome measures

Physical growth parameters, morbidity profile and mortality.

Results

At mean age of 12 months, mean (SD) weight, length and head circumference of late preterms were 7.4 (0.8) kg, 69.2 (2.5) cm and 43.0 (1.1) cm, respectively; which were significantly lower than that of the full term infants [8.7 (1.6) kg, 72.2 (3.1) cm and 44.2 (1.1) cm] (P < 0.001). On univariate analysis, late preterm group was associated with higher odds (95% CI) of being underweight [5.6 (3.4, 5.5)], stunted [3.5 (2.1, 5.8)] and wasted [3.6 (1.9, 6.9)]. On multivariate analysis, only adjusted odds of late preterms becoming underweight by one year was significant [OR 4.1; 95% CI (1.6, 10.4)]. Feeding difficulties, jaundice and re-hospitalization rates were significantly higher in the late preterm group. The median (IQR) episodes per baby for late preterms as compared to terms for diarrhea [1.84 (0,3) vs 1.14 (0,2) (P <0.001)], and fever [1.33 (0,2) vs. 0.95 (0,2) (P = 0.01)] were higher.

Conclusion

Healthy late preterms are at significantly higher risk of being underweight in the first year of life, in addition to having significantly higher morbidity.
  相似文献   
138.
Methoxychlor (MXC), an organochloride insecticide, is a potent toxicant‐targeting female reproductive system and known to cause follicular atresia by inducing apoptosis within granulosa cells. Oxidative stress plays a pivotal role in apoptosis; thus, this study focuses on the ameliorative action of N‐acetyl cysteine (NAC) on MXC‐induced oxidative stress and apoptosis within granulosa cell of caprine ovary. Classic histology, fluorescence assay, and biochemical parameters were employed to evaluate the effect of varied concentration of NAC (1, 5, and 10 mM) on granulosa cell apoptosis after 24, 48, and 72 h exposure duration. Histomorphological studies revealed that NAC diminished the incidence of apoptotic attributes like condensed or marginated chromatin, pyknosis, crescent‐shaped nucleus, empty cell spaces, and degenerated cellular structure along with the presence of cytoplasmic processes within granulosa cells in dose‐ and time‐dependent manner. NAC significantly downregulated the percentage of MXC‐induced granulosa cell apoptosis within healthy ovarian follicle with its increasing dose, maximum at 10 mM concentration. It also significantly (p < 0.05) upregulated the activity of antioxidant enzymes, namely catalase, superoxide dismutase, and glutathione‐s‐transferase, along with ferric reducing antioxidant power further declining lipid peroxidation in the MXC‐treated caprine ovary. The results revealed a negative correlation between apoptosis frequency and antioxidant enzymes’ activity (r CAT = ?0.67, r SOD = ?0.56, r GST = ?0.31; p < 0.05) while a positive correlation was observed with lipid peroxidation (r = 0.63; p < 0.05) after NAC supplementation. Thus, NAC supplementation reduces the MXC‐generated oxidative stress that perhaps declines the ROS generating signal transduction pathway of apoptosis, thereby preventing MXC‐induced granulosa cell apoptosis and follicular atresia. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 156–166, 2017.  相似文献   
139.
Loss of skeletal muscle mass and function results in loss of mobility for elderly patients. Novel therapies that can protect and/or restore muscle function during aging would have profound effects on the quality of life for this population. Growth differentiation factor 11 (GDF11) has been proposed as a “youthful” circulating factor that can restore cardiac, neural, and skeletal muscle functions in aging animals. However, conflicting data has been recently published that casts doubt on these assertions. We used a complex rat model of skeletal muscle injury that physiologically mimics injuries seen in patients; to investigate the ability of GDF11 and to enhance skeletal muscle regeneration after injury in older rats. Our data showed that GDF11 treatment resulted in a significant increase in tissue fibrosis, accompanied by attenuated functional recovery, as compared to animals treated with vehicle alone. GDF11 impaired the recovery of skeletal muscle function in older rats after injury.  相似文献   
140.
DDT and pyrethroid resistance in Culex quinquefasciatus have been previously reported in Sri Lanka, but the mechanisms involved have yet to be characterized. We report the presence of two mutant alleles of the sodium channel gene, the target site for both DDT and pyrethroid insecticides. Both mutations resulted in classic knockdown resistance (kdr) L1014F mutation because of either an A-to-T substitution or an A-to-C substitution. We developed two alternative assays to distinguish between the two mutations and used these to screen 214 individuals from nine geographic locations throughout Sri Lanka. Very high levels of kdr mutations were found throughout the country. A predominance of the A-to-C mutation was observed over the A-to-T with an average allele frequency of 50% and 2%, respectively. In addition to these non-synonymous kdr substitutions, we also found an indel (TCACA) in the intron downstream of the kdr mutation. After genotyping this indel in 136 individuals, we found no evident correlation between kdr genotypes and intronic indel. The presence of two alternative kdr mutations has implications for the reliance on single molecular diagnostics for detection of resistance in field populations. Furthermore, the high levels of these kdr mutations in C. quinquefasciatus populations throughout Sri Lanka are of concern for the future of pyrethroid-based control programmes on this island.  相似文献   
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