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991.
George Christodoulou M.D. Mathieu Powell M.D. Van‐Hung Nguyen M.D. Kevin Watters M.D. Fatemeh Jafarian M.D. 《Pediatric dermatology》2014,31(6):e164-e166
Bullous systemic lupus erythematosus (BSLE) is a rare autoimmune subepidermal blistering disease with a female predominance characterized as an acute vesicobullous eruption in patients with systemic lupus erythematosus (SLE). Here we report a case of BSLE in a 16‐year‐old boy that does not adhere to the criteria originally established and suggest a new outlook on this condition. 相似文献
992.
Tahereh Haghpanah Marefat Ghaffari Novin Reza Masteri Farahani Fatemeh Fadaei-Fathabadi Maryam Dehghani-Mohammadabadi 《Systems biology in reproductive medicine》2016,62(1):1-10
Common methods employed in assisted reproduction technology (ART) include intracytoplasmic sperm injection (ICSI) with an unspecified level of sperm DNA fragmentation (SDF) and preimplantation genetic diagnosis (PGD). The aim of this study was to investigate the impact of SDF on human preimplantation embryo development and the incidence of apoptosis following a single blastomere biopsy. Using sperm chromatin dispersion (SCD) to assess SDF, a total of 20 processed semen samples were categorized into two groups; group I: SDF ≤30% and group II: SDF >30%. After ICSI, fertilization, cleavage, and embryo quality score were assessed. A single blastomere was biopsied from day 3 embryos and development was monitored on day 4. The frequency of apoptosis in biopsied embryos was assayed by TUNEL and the level of BCL-2, BAX, hsa-mir-15a, and hsa-mir-16-1 were assessed by quantitative real-time polymerase chain reaction (qRT-PCR). SCD was found to be negatively correlated with sperm motility and normal form spermatozoa (p?<?0.05). The rate of fertilization, cleavage, and embryo quality score were not significantly different between the two groups (all p?>?0.05). SDF >30% had no negative effect on potential development and did not increase the proportion of apoptotic cells and the level of apoptosis-related genes and microRNAs (miRNAs) in group II vs. group I (p?>?0.05). It appears that at the levels assessed paternal genome damage had little if any negative effect on preimplantaton embryo development and apoptosis following single blastomere biopsy. This may reflect the selection of morphologically normal sperm for ICSI and the repair capacity of the oocyte. 相似文献
993.
S. Taghipour Zahir M. Mortaz M. Baghi Yazdi N. Sefidrokh Sharahjin M. Shabani 《Neuro-Chirurgie》2018,64(1):76-78
Glioblastoma multiforme (GBM) is a high grade glial tumor, primarily located in cerebral hemispheres. The most common clinical presentations are slowly progressive neurological deficit such as motor weakness, seizure, and headaches that last less than three months. Calvarium and extra-axial invasion are very rare and generally occur after a brain biopsy or surgery, or secondary to radiotherapy of primary intra-axial glial tumors. We report a case of GBM with calvarium involvement in a 60-year-old man who presented with a frontal bump and left-sided clumsiness. Imaging studies revealed a tumoral lesion that destroyed the frontal bone with white matter involvement of the frontal lobe and extension into the corpus callosum. Histopathological examination of intra-axial and extra-axial lesions revealed pleomorphic high-grade tumor with large areas of necrosis and hemorrhage. Immunohistochemical (IHC) studies confirmed GBM that spread directly into the dura, galea, and calvarium (positive reaction for GFAP, S-100, CD68, OLIG2, and p53). The patient was treated with radiotherapy (60 Gy/30 fractions) and concomitant temozolomide. Unfortunately, the patient died seven months after the initial diagnosis. 相似文献
994.
Mohammad Taghi Bahreyni Toossi Mahdi Ghorbani Fatemeh Akbari Mohammad Mehrpouyan Leila Sobhkhiz Sabet 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2016,39(1):113-122
The aim of this study is to evaluate the effect of tooth and dental restoration materials on electron dose distribution and photon contamination production in electron beams of a medical linac. This evaluation was performed on 8, 12 and 14 MeV electron beams of a Siemens Primus linac. MCNPX Monte Carlo code was utilized and a 10 × 10 cm2 applicator was simulated in the cases of tooth and combinations of tooth and Ceramco C3 ceramic veneer, tooth and Eclipse alloy and tooth and amalgam restoration materials in a soft tissue phantom. The relative electron and photon contamination doses were calculated for these materials. The presence of tooth and dental restoration material changed the electron dose distribution and photon contamination in phantom, depending on the type of the restoration material and electron beam’s energy. The maximum relative electron dose was 1.07 in the presence of tooth including amalgam for 14 MeV electron beam. When 100.00 cGy was prescribed for the reference point, the maximum absolute electron dose was 105.10 cGy in the presence of amalgam for 12 MeV electron beam and the maximum absolute photon contamination dose was 376.67 μGy for tooth in 14 MeV electron beam. The change in electron dose distribution should be considered in treatment planning, when teeth are irradiated in electron beam radiotherapy. If treatment planning can be performed in such a way that the teeth are excluded from primary irradiation, the potential errors in dose delivery to the tumour and normal tissues can be avoided. 相似文献
995.
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997.
Fatemeh Rafii J.G.H. Ruseler-Van Embden Yasmin F. Asad 《Digestive diseases and sciences》1997,42(1):133-136
Azoreductase and nitroreductase activities ofbacteria in feces of five patients with ileal reservoirswere evaluated, both at the onset of symptoms ofpouchitis and following recovery after treatment with drugs. All stool samples tested had bacteriawith azoreductase and nitroreductase activities.Azoreductase and nitroreductase activities were higherafter recovery than during attacks of pouchitis. During reestablishment of the normal microflora in theileal reservoirs after pouchitis, the anaerobic bacteriaincreased and the aerobic bacteria decreased. 相似文献
998.
Isolation of Nitrofurantoin-Resistant Mutants of Nitroreductase-Producing Clostridium sp. Strains from the Human Intestinal Tract 总被引:1,自引:0,他引:1
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Five spontaneous nitrofurantoin-resistant mutants (one each of Clostridium leptum, Clostridium paraputrificum, two other Clostridium spp. strains from the human intestinal microflora, and Clostridium perfringens ATCC 3626) were selected by growth on a nitrofurantoin-containing medium. All of the Clostridium wild-type and mutant strains produced nitroreductase, as was shown by the conversion of 4-nitrobenzoic acid to 4-aminobenzoic acid. High-performance liquid chromatography (HPLC) analysis of the mutants during incubation with 50 μg of nitrofurantoin per ml showed the gradual disappearance of the nitrofurantoin peak. The nitrofurantoin peak also disappeared when cell-free supernatants instead of cultures of each of the resistant and wild-type bacteria were used, but it persisted if the cell-free supernatants had been inactivated by heat. At least two of the mutants converted nitrofurantoin to metabolites without antibacterial activity, as was shown by a bioassay with a nitrofurantoin-susceptible Bacillus sp. strain. Nitrofurantoin at a high concentration (50 μg/ml) continued to exert some toxicity, even on the resistant strains, as was evident from the longer lag phases. This study indicates that Clostridium strains can develop resistance to nitrofurantoin while retaining the ability to produce nitroreductase; the mutants metabolized nitrofurantoin to compounds without antibacterial activity. 相似文献
999.