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991.
992.
M R Abd al-Hady O Shehata M el-Mously F S Sallam 《The Journal of laryngology and otology》1990,104(12):927-936
Traumatic head injury is the principal cause of death and serious physical disability in adolescents and young adult. Hearing loss is a common sequela of head trauma. The results of pure tone and auditory brain-stem response (ABR) assessment of minor head injury revealed that 20 per cent of these cases showed impairment of hearing including both conductive and sensorineural hearing loss mostly in the high frequencies loss. ABR findings showed a significant difference of absolute wave V latency and interwave (III-V) latencies at repetition rate 11.1 click/sec., and a highly significant difference at a repetition rate of 51.1 click/sec., compared with the control group. In severe head injury, conductive hearing loss was found in only one case, in which a longitudinal fracture of the temporal bone was identified radiologically. No ABR could be recorded at a repetition rate of 11.1 click/sec. in either ear of this case; this patient died a few days later. Three cases were found with a mixed sensorineural hearing loss; one of them showed a longitudinal fracture radiologically. ABR findings in two cases showed prolongation of wave V and I-V interwave latencies, and the third case showed absence of ABR recording. In comatose patients, an ABR grading system is a more sensitive index of brainstem dysfunction than the simple division of normal versus abnormal ABR waves and interwave latencies. Presence or prolongation of wave V and interwave latency I-V even in one ear is of good prognostic value in the comatosed patient. 相似文献
993.
Intercellular junctions in Ewing sarcoma/primitive neuroectodermal tumor: additional evidence of epithelial differentiation. 总被引:1,自引:0,他引:1
Audrey N Schuetz Brian P Rubin John R Goldblum Bahig Shehata Sharon W Weiss Wendy Liu Mark R Wick Andrew L Folpe 《Modern pathology》2005,18(11):1403-1410
Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) has recently been shown to frequently express cytokeratins, suggesting partial epithelial differentiation. Older ultrastructural studies have documented primitive cell-cell junctions in ES/PNET, reportedly resembling poorly formed desmosomes. Recently, paraffin-reactive antibodies have become available to proteins found in a variety of intercellular junctions indicative of epithelial differentiation, including tight junctions, desmosomes and adherens junctions. We examined intercellular junction protein expression in a large number of genetically confirmed ES/PNET. Formalin-fixed, paraffin-embedded sections from 23 primary and seven recurrent or metastatic cases of genetically confirmed ES/PNET were immunostained for claudin-1 and occludin (tight junction structural proteins), zonula occludens-1 (ZO-1, tight junction linker protein), desmoglein 1/2 (desmosomal adherens protein), desmoplakin (desmosomal structural protein) and E-cadherin (epithelial adherens junction protein), using steam heat-induced epitope retrieval and the Dako Envision system. Cases with >5% positive cells were scored as 'positive'. Normal colonic epithelium and skin served as external positive controls. Claudin-1 was expressed by 19 of 30 specimens (63%), ZO-1 was expressed by 15 of 29 specimens (51%), and occludin was expressed by three of 28 specimens (11%). In 28 specimens all three tight junction markers were evaluable. In all, 15 samples (54%) expressed only one tight junction marker, and 10 samples (36%) expressed two tight junction markers. No case expressed all three tight junction markers. Desmoglein was expressed in one of 30 (3%) samples. Desmoplakin was expressed in two of 28 (7%) samples. E-cadherin was negative in all cases. Our data suggest that many of the previously described cell-cell junctions in ES/PNET are poorly formed tight junctions, given the high frequency of claudin-1 and ZO-1 expression. This may underestimate the true frequency of tight junction protein expression in ES/PNET, as there are at least 20 different claudins and other ZO proteins. These tight junctions are almost certainly abnormal, given the absence of occludin expression in most cases. Desmosomal and adherens junction protein expression was rare to absent. Our findings provide additional evidence that ES/PNET frequently show partial epithelial differentiation. 相似文献
994.
Thum MY Bhaskaran S Abdalla HI Ford B Sumar N Shehata H Bansal AS 《Human reproduction (Oxford, England)》2004,19(10):2395-2400
BACKGROUND: Our aim was to evaluate the effect of the absolute count of the activation marker (CD69), IgG Fc receptor (CD16) and inhibitor marker (CD94) expression on peripheral blood natural killer (NK) cells on implantation and miscarriage rates after IVF treatment. METHODS: Prospective observational study of 138 randomly selected women who underwent IVF treatment from December 2002 to September 2003. NK cells were identified as CD56(+) (dim + bright) and CD3(-) by flow cytometry. The absolute counts of the CD69(+), CD16(+) and CD94(+)expressing NK cells were recorded and their relation to IVF treatment outcome and miscarriage rate was analysed. RESULTS: The mean (+/-SD) absolute count of the CD56(dim)CD16(+)CD69(+) NK cells for women who had a successful ongoing pregnancy was 0.61 x 10(6)/l (+/-0.31). For those women who failed to achieve a pregnancy, the mean value of the absolute count of CD56(dim)CD16(+)D69(+) NK cells was significantly (P=0.003) higher at 1.66 x 10(6)/l (+/-0.52). The absolute count of CD56(dim)CD16(+)CD94(+) and CD56(dim)CD16(+) NK cells did not show any statistically significant differences between those women with successful and failed IVF treatment. Receiver operating characteristic (ROC) curve analysis was performed to select a CD69 threshold for further statistical analysis. The implantation rate (IR) was significantly lower (13.1%) and miscarriage rate (MR) was significantly higher (66.7%) for women with an absolute CD56(dim)CD16(+)CD69(+) NK cell count of >1.0 x 10(6)/l compared to women with count below this value (IR 28.2% and MR 16.7%). Further analysis of the absolute count of CD56(bright)CD69(+) and CD56(bright)CD94(+) NK cells did not show any significant difference between those women with successful and failed IVF treatment. CONCLUSIONS: An increase in the absolute count of activated NK cells (CD56(dim)CD16(+)CD69(+)) in the peripheral blood is associated with a reduced rate of embryo implantation in IVF treatment. Furthermore, women with high CD56(dim)CD16(+)CD69(+) peripheral blood NK cell absolute count, who are able to achieve pregnancy, have a significantly higher miscarriage rate. 相似文献
995.
Ahmad Tanveer Amjad Muhammad Iqbal Qumer Batool Asmat Noor Anam Jafir Muhammad Hussain Hammad Irfan Muhammad 《Bulletin of environmental contamination and toxicology》2022,109(2):266-271
Bulletin of Environmental Contamination and Toxicology - A case study was conducted to evaluate the microplastics and heavy metals distribution in Pakistani farmland. Wastewater, soil, and... 相似文献
996.
Purpose of Review
Invasive coronary angiography (ICA) is the gold standard for the anatomical assessment of coronary artery disease. In addition, it provides assessment to coronary physiology and myocardial blood flow through fractional flow reserve (FFR). Furthermore, invasive FFR provides a clear road map that helps in the management of suspected coronary artery disease patients especially if an intermediate coronary lesion is considered. Despite all these developments, this invasive technique carries its own risk. Non-invasive coronary assessment using coronary computed tomography angiography (CCTA) is now an established tool for the evaluation of coronary artery disease.Recent Findings
Recent technology allows the measurement of FFR using CCTA imaging. This technique was studied in a number of papers that confirmed its validity, accuracy, clinical utility and cost-effectiveness. However, this technique continues to have some challenges. In this paper, we will review the data related to this new promising technique as well as its clinical implications, limitations and challenges.Summary
FFRCT is a promising tool that will provide valuable clinical information needed in the management of multiple clinical scenarios. It is expected to grow further in the near future and have significant clinical impact once its clinical role is further defined and workflow is simplified.997.
Colon-specific drug delivery has found important applications in the wide array of diseases affecting the lower intestinal tract. Recent developments and advancements in the polymer-based colonic delivery ensure targeted therapeutics with reduced systemic adverse effects. Latest progress in the understanding of polymer science has decorated a polymer-based formulation with a number of special features, which may prove effective in the localized drug targeting at specific sites of the intestine. Upon oral administration, polymeric vehicles or polymer-coated formulations serve to protect the drug from premature release and degradation in the upper gastrointestinal tract. Moreover, it also facilitates the selective accumulation and controlled release of the drug at inflamed sites of the colon. This review article focuses on a wide coverage of major polymers, their modifications, pros and cons, mechanism of colon targeting and applications as a vehicle system for colonic drug delivery, with a special emphasis on the inflammatory bowel disease. 相似文献
998.
This study investigated the influence of fiber reinforcement on the flexural properties of four commercial (Artglass, Belleglass HP, Herculite XRV and Solidex) veneering composites (Series A) and two experimental composites (Series B&C). This study investigated how the composition of the veneering composites influenced the enhancement of strength and modulus produced by fiber reinforcement. The formulation of the experimental composites were varied by changing the filler load (Series B) or the resin matrix chemistry (Series C) to assess the effect these changes would have on the degree of reinforcement. In Series A, the commercial veneering composites were reinforced by an Ultra-High-Molecular-Weight Polyethylene fiber (UHMW-PE/Connect) to evaluate flexural properties after 24 hours and six months. In Series B, experimental composites with the same organic matrix but with different filler loads (40% to 80% by weight) were also reinforced by Connect fiber to evaluate flexural properties. In Series C, experimental composites (Systems 1-4) with the same filler load (76.5% by weight) but with different organic matrix compositions were reinforced by Connect fiber to evaluate flexural properties. For Series B and C, flexural properties were evaluated after 24 hours water storage. All the samples were prepared in a mold 2 mm x 2 mm x 25 mm and stored in distilled water at 37 degrees C until they were ready for flexural testing in an Instron Universal Testing Machine using a crosshead speed of 1 mm/minute. The results showed no significant differences in the flexural strength (FS) between any of the commercial reinforced composites in Series A. The flexural modulus (FM) of the fiber-reinforced Belleglass HP group was significantly higher than for Artglass and Solidex. Water storage for six months had no significant (p>0.05) effect on the flexural strength of three of the four reinforced veneering composites. The flexural strength for Artglass was significantly reduced (p<0.05) by six-month water storage. In Series B, however, increasing the amount of filler loading improved the flexural modulus of the reinforced experimental composite but had no effect on its flexural strength. In Series C, changing the organic matrix formulation had no affect on flexural strength but affected the flexural modulus of the reinforced experimental composite. 相似文献
999.
A new frameshift mutation encoding a truncated amelogenin leads to X-linked amelogenesis imperfecta 总被引:2,自引:0,他引:2
Greene SR Yuan ZA Wright JT Amjad H Abrams WR Buchanan JA Trachtenberg DI Gibson CW 《Archives of oral biology》2002,47(3):211-217
The amelogenin proteins are the most abundant organic components of developing dental enamel. Their importance for the proper mineralization of enamel is evident from the association between previously identified mutations in the X-chromosomal gene that encodes them and the enamel defect amelogenesis imperfecta. In this investigation, an adult male presenting with a severe hypoplastic enamel phenotype was found to have a single base deletion at the codon for amino acid 110 of the X-chromosomal 175-amino acid amelogenin protein. The proband's mother, who also has affected enamel, carries the identical deletion on one of her X-chromosomes, while the father has both normal enamel and DNA sequence. This frameshift mutation deletes part of the coding region for the repetitive portion of amelogenin as well as the hydrophilic tail, replacing them with a 47-amino acid segment containing nine cysteine residues. While greater than 60% of the protein is predicted to be intact, the severity of this phenotype illustrates the importance of the C-terminal region of the amelogenin protein for the formation of enamel with normal thickness. 相似文献
1000.
Simple enumerations of peripheral blood natural killer (CD56+ NK) cells, B cells and T cells have no predictive value in IVF treatment outcome 总被引:3,自引:0,他引:3
Thum MY Bhaskaran S Bansal AS Shehata H Ford B Sumar N Abdalla HI 《Human reproduction (Oxford, England)》2005,20(5):1272-1276
BACKGROUND: To evaluate the association between the absolute counts of the peripheral natural killer (NK) cells (including total CD56(+) NK cells, CD56(dim) NK cells and CD56(bright) NK cells), B cells and T cells on the implantation rate and miscarriage rate after IVF treatment. METHODS: This was a prospective observation study. A total of 138 patients who underwent IVF treatment from December 2002 to July 2003 were recruited to the study. Blood samples were obtained on the day of vaginal oocyte retrieval prior to the procedure. The absolute counts of lymphocytes, NK cells, B cells and T cells were identified by flow cytometry. These absolute counts and their relationships to IVF treatment outcome and miscarriage rate were analysed. RESULTS: There were no significant differences with regard the mean values of absolute lymphocyte count, T cell count, B cell count and NK cell count (including total CD56(+) NK, CD56(dim) NK and CD56(bright) NK cells) between the pregnant and non-pregnant groups and also between the ongoing pregnancy and miscarriage groups. The cause of infertility, duration of infertility, basal FSH levels, number of previous failed IVF treatments, number of previous miscarriages and stimulation characteristics were not significantly different between the pregnant and non-pregnant groups. Previous studies have suggested that women with a history of recurrent miscarriage and those with infertility accompanied by recurrent failed IVF treatments are associated with a peripheral blood NK cell percentage >12%, therefore further analysis of peripheral CD56(+) NK cell levels <12% (group A) and >12% (group B) was performed. There was no significant difference in implantation rate (group A: 17.0%; group B: 23.2%), pregnancy rate (group A: 36.6%; group B: 47.7%) or miscarriage rate (group A: 23.3%; group B: 28.6%). CONCLUSION: There were no significant differences between simple enumerations of peripheral blood NK cells (including total CD56(+) NK, CD56(dim) NK and CD56(bright) NK cells), B cells and T cells with IVF treatment outcome and pregnancy outcome. Women who had a peripheral NK cell level >12% did not have higher number of previous pregnancy losses. Importantly their pregnancy rate was not reduced and their miscarriages were not increased compared to women who had a peripheral NK cells level <12%. 相似文献