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191.
Malignant granular cell tumor at the retrotracheal space   总被引:3,自引:0,他引:3  
We report a case of an extremely rare neoplasm, malignant granular cell tumor (MGCT). The patient was a 21-year-old woman, who was 5 months pregnant. The tumor occurred in the retrotracheal space, extending from the level of the larynx to the thoracic inlet. In addition, there were multiple, variable-sized tumor nodules within both lung fields on chest CT scan. Histologically, tissue biopsied from the periphery of the tumor consisted of solid sheets of large ovoid cells with ample, eosinophilic cytoplasm, eccentric nuclei, and prominent nucleoli. Each cell showed slight atypism of the nuclei. There was a focal necrosis at the periphery of the lesion. These cells stained strongly for S-100 protein, neuron-specific enolase (NSE) and CD68. On electron microscopy, the tumor cells contained autophagic vacuoles. The patient refused further treatment and died 7 months later. The exact cause of death was not known. Until now, the diagnosis of MGCTs has been made only when metastasis and an aggressive clinical course are identified, although some observers advocate that some histologic features such as nuclear pleomorphism, necrosis, and the presence of any mitotic activity are indicative of malignancy. These histologic findings are not easily detectable in every case of MGCT, as in our case. So the diagnosis of a MGCT should be considered in cases with aggressive clinical findings and some histologic features, such as necrosis, nuclear atypism, and mitotic activities, which could suggest the malignant behavior of this neoplasm.  相似文献   
192.
BackgroundChronic kidney disease (CKD) has a negative impact on growth and development in children and is a risk factor for neurocognitive impairment; however, there is limited research on the cognitive function of children and adolescents with CKD. This study therefore aimed to investigate the mean intelligence and risk factors for low intelligence in children and adolescents with CKD.MethodsEighty-one patients with CKD under 18 years old were included in the KoreaN cohort study for Outcomes in patients With Pediatric Chronic Kidney Disease (KNOW-Ped CKD). Participants completed either the Wechsler Intelligence Scale for Children (6–16 years), or Wechsler Adult Intelligence Scale (> 16 years).ResultsThe mean full-scale intelligence quotient (IQ) was 91 ± 19; 24.7% of participants scored a full-scale IQ below 80. Participants with a short stature (height Z scores < −1.88), failure to thrive (weight Z scores < −1.65), more severe CKD stage (≥ IIIb), longer duration of CKD (≥ 5 years), and those who were Medicare or Medicaid beneficiaries, had significantly lower mean full-scale IQs.ConclusionOn linear regression analysis, the association between the full-scale IQ, and longer duration of CKD and growth failure, remained significant after controlling for demographic and clinical variables. It is therefore necessary to investigate cognitive impairment in pediatric patients with CKD who exhibit growth failure or for a longer postmorbid period. It is believed that early interventions, such as kidney transplantation, will have a positive effect on IQ in children with CKD, as the disease negatively affects IQ due to poor glomerular filtration rate over time.Trial RegistrationClinicalTrials.gov Identifier: NCT02165878  相似文献   
193.

Background/purpose

This study investigated the distribution and persistence of multidrug resistant organisms (MDROs) including methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Enterobacteriaceae (CRE), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and multidrug-resistant Acinetobacter baumannii (MDRAB) in six long-term care facilities (LTCFs).

Methods

We investigated the distribution of MDROs in residents of six LTCFs and their environments from January to December 2016 (intervention period). Active surveillance of colonization of MDROs was performed by culturing rectal and nasal swab samples from the residents every three months. Multilocus sequence typing (MLST) was conducted, and genes for panton-valentine leukocidin (PVL) from MRSA isolates were determined.

Results

A total of 521 samples were positive for MDROs, and MRSA was the most common organism (65.1%), followed by MDRAB (11.3%), carbapenem-resistant Klebsiella pneumoniae (11.1%), carbapenem-resistant Escherichia coli (4.6%), and carbapenem-resistant P. aeruginosa (2.1%, n = 11). By a linear regression model, positive MRSA isolates from the environment were found to be statistically significant and associated with the number of colonized LTCF residents (p = 0.01), while the timing of the surveillance culture was not (p = 0.227). The main MLST types associated with PVL-production were sequence type (ST) 59, (40.0%, 24/60), ST30 (21.4%, 3/14), ST8 (87.5%, 14/16), and ST45 (3.6%, 1/28). The susceptibility rates of tetracycline (96.7%), trimethoprim-sulfamethoxazole (96.7%), and ciprofloxacin (81.7%) were statistically significant and higher in MRSA ST59, compared to the rates in MRSA ST45 isolates.

Conclusions

MRSA was the most commonly colonized MDRO, both in the LTCF residents and in the environment, followed by MDRAB and carbapenem-resistant K. pneumoniae.  相似文献   
194.
目的 探查间质核 (INV)内内脏传入终末与向臂旁核 (PBN)投射的NOS阳性神经元之间的联系。 方法 逆行、跨神经节追踪以及免疫荧光组织化学方法 ,结合激光共聚焦扫描显微镜观察。 结果 PBN内注射四甲基罗丹明 (TMR)后 ,逆行标记细胞主要位于注射侧的INV ,大多属 2 0 μm以下的中、小型细胞。NOS阳性细胞与TMR逆行标记细胞分布区域重叠。NOS TMR双标记细胞分别占NOS阳性细胞总数的 5 4 8% (17 31)和TMR逆行标记细胞总数的 34% (17 4 9)。舌咽和迷走神经内注射生物素化葡聚糖胺 (BDA)跨神经节标记的内脏神经初级传入终末点状膨体贴近双标记细胞胞体 ,呈紧密接触状。 结论 可能存在经INV向PBN投射的内脏伤害性信息传导通路 ,作为神经递质和神经信息分子的NO可能参与其内脏伤害性信息的传递和调控  相似文献   
195.
An inactivated SVDV antigen is used in current enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies to swine vesicular disease virus (SVDV). To develop a noninfectious recombinant alternative, we produced SVDV-like particles (VLPs) morphologically and antigenically resembling authentic SVDV particles by using a dual baculovirus recombinant, which expresses simultaneously the P1 and 3CD protein genes of SVDV under different promoters. Antigenic differences between recombinant VLPs and SVDV particles were not statistically significant in results obtained with a 5B7-ELISA kit, indicating that the VLPs could be used in the place of SVDV antigen in ELISA kits. We developed a blocking ELISA using the VLPs and SVDV-specific neutralizing monoclonal antibody 3H10 (VLP-ELISA) for detection of SVDV serum antibodies in pigs. The VLP-ELISA showed a high specificity of 99.9% when tested with pig sera that are negative for SVDV neutralization (n = 1,041). When tested using sera (n = 186) collected periodically from pigs (n = 19) with experimental infection with each of three different strains of SVDV, the VLP-ELISA detected SVDV serum antibodies as early as 3 days postinfection and continued to detect the antibodies from all infected pigs until termination of the experiments (up to 121 days postinfection). This test performance was similar to that of the gold standard virus neutralization test and indicates that the VLP-ELISA is a highly specific and sensitive method for the detection of SVDV serum antibodies in pigs. This is the first report of the production and diagnostic application of recombinant VLPs of SVDV. Further potential uses of the VLPs are discussed.  相似文献   
196.
运用灰色系统理论中的 T型关联度分析方法 ,对类金刚石 (DL C)薄膜、富石墨相 DL C薄膜和富金刚石相 DL C薄膜三种 DL C薄膜进行了碳相成分对其白蛋白 (HSA)、纤维蛋白原 (HFG)、免疫球蛋白 (Ig G)三种血浆蛋白吸附量影响的定量分析研究。合理地解释了三种材料蛋白吸附量随碳相成分变化的实验结果 ,并得出如下重要的分析结论 :(1)石墨和 C- H相对 HSA的吸附影响较大 ,随着二者的增加 ,HSA的吸附量下降 ;(2 )与 HFG吸附有较强关联的碳相成分是 DL C相和 C- O相 ,前者呈负相关 ,后者为正相关 ;(3)各碳相成分对 Ig G的吸附均有性质不尽相同的影响 ,但程度有限 ,且彼此间相差不大 ;(4 ) DL C碳相具有增强 HSA吸附、抑制 HFG、Ig G吸附的双重功效 ,其对 DL C薄膜血液相容性的影响远较其它碳相成分更为重要。  相似文献   
197.
In the present experiment, we characterized the intracellular Ca2+ oscillations induced by caffeine (1 mM) or histamine (1–3 M) in voltage-clamped single smooth muscle cells of rabbit cerebral (basilar) artery. Superfusion of caffeine or histamine induced periodic oscillations of large whole-cell K+ current with fairly uniform amplitudes and intervals. The oscillatory K+ current was abolished by inclusion of ethylenebis(oxonitrilo)tetraacetate (EGTA, 5 mM) in the pipette solution. Caffeine- and histamine-induced periodic activation of the large-conductance Ca2+-activated K+ [K(Ca)] channel was recorded in the cell-attached patch mode. These results suggest that the oscillations of K+ current are carried by the K(Ca) channel and reflect the oscillations of intracellular Ca2+ concentration ([Ca2+]i). Ryanodine (1–10 M) abolished both caffeine- and histamine-induced oscillations. Caffeine- induced oscillations were abolished by the sarcoplasmic reticulum Ca2+-adenosine 5-triphosphatase (Ca2+-ATPase) inhibitor, cyclopiazonic acid (10 M), and a high concentration of caffeine (10 mM). Inclusion of heparin (3 mg/ml) in the pipette solution blocked histamine-induced oscillations, but did not block caffeine-induced oscillations. By the removal of extracellular Ca2+, but not by the addition of verapamil and Cd2+, the caffeine-induced oscillations were abolished. Increasing Ca2+ influx rate increased the frequencies of caffeine-induced oscillations. Spontaneous oscillations were also observed in cells that were not superfused with agonists, and had similar characteristics to the caffeine-induced oscillations. From the above results, it is concluded, that in smooth muscle cells of the rabbit cerebral (basilar) artery, ryanodine-sensitive Ca2+-induced Ca2+ release pools play key roles in the generation of caffeine- and histamine-induced intracellular Ca2+ oscillations.  相似文献   
198.
This study investigated a previously unaccounted for source of error in a high-capacity, six degree-of-freedom load cell used in multi-degree-of-freedom robotic testing of musculoskeletal joints, an application requiring a load cell with high accuracy in addition to high load capacity. A method of calibration is presented for reducing the error caused by changes in universal force-moment sensor (UFS) orientation within a gravitational field. Uncorrected, this error can exceed a magnitude of 1% of the full-scale load capacity—the manufacturer-stated accuracy of the UFS. Implementation of the calibration protocol reduced this error by approximately 75% for a variety of loading conditions. This improvement in load cell accuracy (while maintaining full load capacity) should improve both the measurement and control of specimen kinetics by robotic/UFS and other biomechanical testing systems. © 1999 Biomedical Engineering Society. PAC99: 8719Rr, 8780Vt, 0620Fn, 0620Dk, 8719Ff  相似文献   
199.
Hua ZC  Sohn SJ  Kang C  Cado D  Winoto A 《Immunity》2003,18(4):513-521
FADD is an adaptor known to transmit apoptotic signals from members of the tumor necrosis factor receptor family. We show here that FADD has a domain implicated in cell proliferation. Mice bearing the Asp mutation in the serine 191 phosphorylation site are runted and anemic and display splenomegaly. Apoptosis is unimpaired in these mice, but they exhibit many immune developmental problems indicative of proliferative defects. Mutant FADD T cells are defective in cell cycle progression, suggesting that regulation of phosphorylation at serine 191 is essential for growth/proliferation. Remarkably, serine 191 is conserved among mammalian FADD proteins, but this C-terminal region is absent in lower organisms, suggesting that FADD acquired a domain during evolution, rendering it a "proliferation-apoptosis coupler" that balances cell proliferation and apoptosis.  相似文献   
200.
The effect of a competitive soccer match on maximal power performance was assessed on 19 members of an NCAA Division III female soccer team. Performance testing occurred within 24 hours prior to the game (Pre), immediately postgame (IP), and 24 hours postgame (24P). Each subject performed a squat jump (SJ) and countermovement jump (CMJ). Comparisons between starters (n = 10) and nonstarters (n = 9) revealed no between-group differences in power performance at IP, but starters were found to have significantly lower power and force measures at 24P than nonstarters. There were significant correlations between playing time and peak force during the SJ at 24P (r = -0.47), and between playing time and peak power during the SJ at IP (r = -0.57) and 24P (r = -0.51), and during the CMJ at IP (r = -0.49). Comparisons between different positions revealed no differential fatigue patterns. Results of this study show that power performance appears to be maintained for the duration of a soccer match but declines significantly within 24 hours after the match. Position played does not appear to affect performance decrements seen at 24 hours postmatch.  相似文献   
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