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排序方式: 共有222条查询结果,搜索用时 15 毫秒
131.
BACKGROUND: Desmoplastic infantile ganglioglioma (DIG) is a rare WHO Grade I tumor of infancy that is characterized by large volume, superficial location, invariable supratentoriality, fronto-parietal lobe predilection and morphologically, by an admixture of astroglial and neuroepithelial elements in a desmoplastic milieu. With over 50 cases described, the histologic and radiographic spectrum of DIG has been well-characterized. The superficial location of DIGs may render them greatly amenable to preoperative assessment utilizing aspiration cytology; however, the cytologic features of this rare tumor have only been reported once previously. CASE PRESENTATION: We present herein cytomorphologic findings from the intraoperative aspiration of a typical case of DIG diagnosed in a 1-year-old male. As evaluated on a single liquid-based preparation, the specimen showed low cellularity and was comprised predominantly of a population of dispersed (occasionally clustered) large neuronal cells with eccentrically located hyperchromatic nuclei (which were occasionally binucleated) and abundant unipolar cytoplasm. Rare smaller astroglial cells were intermixed. Despite the tumor's characteristic desmoplastic histologic appearance, no stromal fragments were identified on the aspiration material. CONCLUSIONS: A differential diagnosis is presented and analyzed in detail and it is concluded that when these large neuronal cells are encountered in an aspirate of a brain mass in a child, a combination of clinical, radiologic and immunohistochemical parameters can eliminate most of the differential possibilities. 相似文献
132.
Idris R Trifonova R Puschenreiter M Wenzel WW Sessitsch A 《Applied and environmental microbiology》2004,70(5):2667-2677
Thlaspi goesingense is able to hyperaccumulate extremely high concentrations of Ni when grown in ultramafic soils. Recently it has been shown that rhizosphere bacteria may increase the heavy metal concentrations in hyperaccumulator plants significantly, whereas the role of endophytes has not been investigated yet. In this study the rhizosphere and shoot-associated (endophytic) bacteria colonizing T. goesingense were characterized in detail by using both cultivation and cultivation-independent techniques. Bacteria were identified by 16S rRNA sequence analysis, and isolates were further characterized regarding characteristics that may be relevant for a beneficial plant-microbe interaction-Ni tolerance, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase and siderophore production. In the rhizosphere a high percentage of bacteria belonging to the Holophaga/Acidobacterium division and alpha-Proteobacteria were found. In addition, high-G+C gram-positive bacteria, Verrucomicrobia, and microbes of the Cytophaga/Flexibacter/Bacteroides division colonized the rhizosphere. The community structure of shoot-associated bacteria was highly different. The majority of clones affiliated with the Proteobacteria, but also bacteria belonging to the Cytophaga/Flexibacter/Bacteroides division, the Holophaga/Acidobacterium division, and the low-G+C gram-positive bacteria, were frequently found. A high number of highly related Sphingomonas 16S rRNA gene sequences were detected, which were also obtained by the cultivation of endophytes. Rhizosphere isolates belonged mainly to the genera Methylobacterium, Rhodococcus, and Okibacterium, whereas the majority of endophytes showed high levels of similarity to Methylobacterium mesophilicum. Additionally, Sphingomonas spp. were abundant. Isolates were resistant to Ni concentrations between 5 and 12 mM; however, endophytes generally tolerated higher Ni levels than rhizosphere bacteria. Almost all bacteria were able to produce siderophores. Various strains, particularly endophytes, were able to grow on ACC as the sole nitrogen source. 相似文献
133.
Fairchild AS Smith JL Idris U Lu J Sanchez S Purvis LB Hofacre C Lee MD 《Applied and environmental microbiology》2005,71(10):5865-5872
There is a growing concern that antibiotic usage in animal production has selected for resistant food-borne bacteria. Since tetracyclines are common therapeutic antibiotics used in poultry production, we sought to evaluate the effects of oral administration on the resistance of poultry commensal bacteria and the intestinal bacterial community structure. The diversity indices calculated from terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA amplicons did not indicate significant changes in the cecal bacterial community in response to oxytetracycline. To evaluate its effects on cultivable commensals, Enterococcus spp., Escherichia coli, and Campylobacter spp. were isolated from the cecal droppings of broiler chickens. Enterococcus spp. and E. coli expressed tetracycline MICs of >8 microg/ml and harbored a variety of tet resistance determinants regardless of the tetracycline exposure history of the birds. The enterococcal isolates possessed tetM (61%), tetL (25.4%), and tetK (1.3%), as well as tetO (52.5%), the determinant known to confer a tetracycline resistance phenotype in Campylobacter jejuni. E. coli isolates harbored tetA (32.2%) or tetB (30.5%). Tetracycline MICs remained at <2 microg/ml for Campylobacter isolates before and after tetracycline treatment of the chickens, even though isolates expressing MICs of >16 mug/ml were commonly cultured from flocks that did not receive oxytetracycline. The results imply that complex ecological and genetic factors contribute to the prevalence of antibiotic resistance arising from resistance gene transfer in the production environment. 相似文献
134.
Wael Ammar Aldaddou Abdullah S. M. Aljohani Idris Adewale Ahmed Naser A. Al-Wabel Ibrahim M. El-Ashmawy 《化学与生物多样性》2023,20(7):e202300115
Most heavy metals and industrial chemicals such as nicotine and lead cause harm to the reproduction process through a decrease in sperm motility, fertilization process, and sperm binding to the oocyte. Salvia officinalis L. (sage) has been reported to enhance serum testosterone levels and other certain biochemical enzymes. Thus, the current study is aimed at evaluating the potential health benefits of S. officinalis L. methanol extract on lead and nicotine hydrogen tartrate-induced sperm quality degeneration in male rats and also identifying some of the non-polar volatile bioactive compounds that might be attributed to the bioactivity of S. officinalis extract using gas chromatography-mass spectrometry (GC/MS). In the study, fifty-four mature male albino rats of about 220–250 g [were divided randomly and equally into 9 groups (n=6)]. Sperm quality degeneration was induced through the oral administration of 1.5 g/L of lead acetate in drinking water or peritoneal injection of 0.50 mg/kg (animal weight) nicotine hydrogen tartrate for sixty days. Two doses (200 & 400 mg/kg b.w.) of S. officinalis L. were used. The rats were anesthetized after the experimental period and then sacrificed. Blood samples were collected while the epididymis, testicle, and accessory sex organs (prostates and seminal vesical) were taken for histopathological studies. Twelve major compounds were identified through the GC/MS analysis of S. officinalis L. methanol extract. Lead and nicotine toxicity had a great effect on the rats’ sperm quality causing a significant (p<0.05) decrease in the quantity of sperm and sperm motility as well as an upsurge in the abnormalities of the sperm and a reduction in the length & diameter of seminiferous tubules and size & weight of sexual organs (accessory sex glands, epididymis, and testis). The administration of S. officinalis L. methanol extract, however, had a positive impact on the sexual organ weights, semen quality & quantity, and rats’ fertility, thus, ameliorating the adversative effects of both lead and nicotine. Further evaluation and isolation of the bioactive components are recommended as potential drug leads. 相似文献
135.
Alex George Idris Raji Bekir Cinar Omer Kucuk Adegboyega K. Oyelere 《Bioorganic & medicinal chemistry》2018,26(8):1481-1487
Androgen receptor (AR) signaling is vital to the viability of all forms of prostate cancer (PCa). With the goal of investigating the effect of simultaneous inhibition and depletion of AR on viability of PCa cells, we designed, synthesized and characterized the bioactivities of bifunctional agents which incorporate the independent cancer killing properties of an antiandrogen and genistein, and the AR downregulation effect of genistein within a single molecular template. We observed that a representative conjugate, 9b, is much more cytotoxic to both LNCaP and DU145 cells relative to the antiandrogen and genistein building blocks as single agents or their combination. Moreover, conjugate 9b more effectively down regulates cellular AR protein levels relative to genistein and induces S phase cell cycle arrest. The promising bioactivities of these conjugates warrant further investigation. 相似文献
136.
137.
Murat Kaya Vykintas Baublys Idris Sargin Ingrida Šatkauskienė Algimantas Paulauskas Bahar Akyuz Esra Bulut Vaida Tubelytė Talat Baran Osman Seyyar Mahmut Kabalak Huseyin Yurtmen 《Food biophysics》2016,11(1):10-19
Chitin specimens from 16 arthropod species (13 of Insecta and 3 of Arachnida) were isolated for the first time using the same method. Fourier Transform Infrared Spectrometry (FTIR), Thermogravimetric Analysis (TGA), X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and elemental analysis have been applied to determine how physicochemical properties of chitin specimens are affected by taxonomic relationship. The characterisation studies revealed that physicochemical nature of the chitin specimens differed greatly and were found partially specific to taxa. Significant differences in the surface morphologies of chitin specimens were observed even in the same order. However, the chitin contents were recorded to be specific to the order in the class Insecta. The highest chitin content was observed in Coleoptera (18.2–25.2 %) followed by Hemiptera (10.6–14.5 %), Odonata (9.5–10.1 %), Hymenoptera (7.8–9.3 %), Diptera (8.1 %), Blattodea (4.7 %). In addition, the crystalline index (CrI) values of chitin specimens from Coleoptera were found to be higher than the other orders in Insecta. This study revealed that the chitin contents and CrI values can be related to taxonomical relationships. 相似文献
138.
139.
Murat Kaya Esra Bulut Muhammad Mujtaba Karolis Sivickis Idris Sargin Bahar Akyuz Sevil Erdogan 《Archives of insect biochemistry and physiology》2016,93(2):96-109
Earlier reports have established that chitin isolates from each body part of an insect cuticle can exhibit diverse physicochemical properties. But it is still unknown if the gender of the insect can influence characteristics of chitin isolates from different body parts. The present study addresses this question. As a result, important physicochemical differences in the chitin samples from different body parts of Melolontha sp. were recorded on the basis of sex. The chitin samples were extracted from eight different body parts (antennae, head, eyes, thorax, abdomen, elytra, hindwings, and legs) of female and male. The most remarkable variations in the chitin isolates from female and male body parts were recorded in chitin content, crystallinity, thermal stability, and surface morphology. And also it was wondered these chitin isolates from different body parts of female and male could find different applications. To check this hypothesis, the chitin samples from female and male were interacted with bovine serum albumin (BSA) protein and important variations were observed. 相似文献
140.