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排序方式: 共有545条查询结果,搜索用时 15 毫秒
141.
The new species Acantholimon doganii Y. Bağcı, Doğu & Akaydın is described and illustrated. Diagnostic morphological characteristics in closely related species are discussed and the conservation status of the new species is analysed. A revised key to the Turkish Acantholimon species with persistent circinnate leaf basis is also provided. 相似文献
142.
Substituted polyaniline/chitosan(PANIs/Ch) composites were chemically synthesized by using ammonium peroxydisulfate as oxidant and characterized by measurements of conductivity, FTIR, UV–vis, SEM and TGA techniques. FTIR spectra of the composites revealed that there is a strong interaction between substituted polyanilines and chitosan. Among the substituted polyaniline/chitosan composites synthesized, poly(N-ethylaniline)/chitosan PNEANI/Ch has the highest conductivity with a value of 1.68 × 10?4 S/cm. The P2EANI/Ch composite exhibited higher thermal stability than the other composites. SEM images of the composites showed an agglomerated granular morphology of substituted polyaniline particles coated on the surface of chitosan. 相似文献
143.
Erdem Yavuz Gülay Bayramoğlu B. Filiz Şenkal M. Yakup Arıca 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(14-15):1479-1486
Crosslinked-poly(vinylbenzylchloride), poly(VBC), beads were prepared by suspension polymerization and poly(glycidylmethacrylate) was grafted by surface-initiated-atom radical polymerization (SI-ATRP) technique. Epoxy groups of the grafted poly(GMA) were reacted with hydrazine and ammonia to create an affinity binding sites. The hydrazine and amine functionalized poly(VBC-g-GMA) beads were used as an affinity support for adsorption of invertase from solution and yeast crude extract. The influence of pH, equilibrium time, ionic strength and initial invertase concentration on the adsorption capacities of both hydrazine and amine functionalized beads has been investigated. Maximum invertase adsorptions onto hydrazine and amine functionalized beads, were 86.7 and 30.4 mg/g at pH 4.0 and 5.5, respectively. The experimental equilibrium data fitted well to the Temkin isotherm model. Finally, the hydrazine functionalized poly(VBC-g-GMA) beads were used for the purification of invertase from crude yeast extract in a batch system and the purity of the eluted invertase from the hydrazine functionalized beads was determined as 92% by HPLC from single step purification protocol. 相似文献
144.
E. Rencüzoğullari H. B. İla A. Kayraldiz S. B. Diler A. Yavuz M. Arslan F. Funda Kaya M. Topaktas 《Russian Journal of Genetics》2006,42(6):623-627
The aim of this study was to investigate the mutagenic and antimutagenic effects of Ecballium elaterium (EE) fruit juice, which has an anti-inflammatory effect, using in vitro human peripheral lymphocytes. To investigate the
mutagenic effects of the EE fruit juice, human peripheral lymphocytes were treated with three doses (18, 36, and 72 μl/l)
of fruit juice alone for 24 and 48 h. For investigating the antimutagenic effects of the EE fruit juice, the human lymphocytes
were also treated with the mixture of the fruit juice and 0.25 μg/ml MMC. The EE fruit juice induced the percentage of total
CA when used alone (especially the percentage of structural CA than the percentage of the numerical CA) and synergically induced
the percentage of total CA when used as a mixture with MMC. The EE fruit juice did not affect the SCE frequency for 24 and
48 h treatment time. In contrast, EE and MMC as a mixture sinergically induced the SCE frequency at the highest concentration
for 48 h treatment time only. EE alone did not decrease the RI while it decreased the MI in a dose-dependent manner. EE and
MMC as a mixture have a higher cytotoxic effect than the cytotoxic effects of EE alone. As a result, it can be concluded that
EE had no antimutagenic effect while EE had a mutagenic and a cytotoxic effect in human peripheral lymphocytes.
This article was submitted by the authors in English. 相似文献
145.
Zoledronic acid is synergic with vinblastine to induce apoptosis in a multidrug resistance protein-1 dependent way: an in vitro study 总被引:2,自引:0,他引:2
Yildiz M Celik-Ozenci C Akan S Akan I Sati L Demir R Savas B Ozben T Samur M Ozdogan M Artac M Bozcuk H 《Cell biology international》2006,30(3):278-282
We have explored the action of zoledronic acid, which has an apoptotic effect and is used as an agent for treating skeletal metastases and osteoporosis, in the presence of vinblastine, and whether this effect is associated with MRP-1 (multidrug resistance protein-1) expression. HEK (human embryonic kidney) 293 cells were transfected to form the multidrug resistant cell line designated 293MRP (MRP-1 expressing HEK293 cells). Both lines were treated with varying concentrations of vinblastine and zoledronic acid. Apoptosis was determined by the TUNEL (deoxyuridine triphosphate nick end-labeling) method. The type of treatment, MRP-1 expression status, and the type of treatment with respect to MRP-1 expression status significantly affected (P < 0.001) the degree of apoptosis. The largest increase in cytotoxicity was noted in HEK293 cells, when 100 micromol zoledronic acid was added to 4 microg/ml vinblastine (an increment of 80.3%, P < 0.001). This preliminary work shows that zoledronic acid acts synergistically with vinblastine to induce apoptosis in an MRP-1 dependent way. 相似文献
146.
147.
Günhan O Yildiz E Karslioğlu Y Aydintuğ Y Doğan N Celasun B 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2003,25(2):85-89
OBJECTIVE: To investigate the nuclear morphometric features of epithelial cells lining keratocysts and some other odontogenic cysts. STUDY DESIGN: All cases were selected from the archives of the Department of Pathology, Gülhane Military Medical Academy, as follows: 20 keratocysts and 10 dentigerous and 10 radicular cysts. Nuclear morphometric variables were measured on hematoxylin and eosin-stained histologic slides. Basal and intermediate cells of the epithelium were evaluated separately. Nuclei of the cells were outlined interactively and measured using a specially written macro program. Area, feret ratio (ratio of the longest nuclear axis to the shortest one) and circularity (F circle) of the nuclei were calculated. Additionally, nuclear densitometric analysis was performed on the keratocyst cases. RESULTS: The number of cells in the basal layer (cell density) was higher in keratocysts than in other cysts. The mean nuclear area of basal cells was smaller than of intermediate cells in both keratocysts and other cysts (P < .001). The feret ratio values revealed that basal cell nuclei of keratocysts were more ovoid as compared to those of other cysts (P < .001). Nuclear densitometric findings showed that the DNA indices of all keratocyst cases were close to 1.0, and the cells were considered diploid. CONCLUSION: Increased cell density, a more ovoid nuclear shape and more variation in the size of basal layer cell nuclei in keratocysts were helpful in differentiating these lesions from other odontogenic cysts. 相似文献
148.
Celik-Ozenci C Catalanotti J Jakab A Aksu C Ward D Bray-Ward P Demir R Huszar G 《Biology of reproduction》2003,69(4):1347-1355
The relationship between abnormal sperm morphology and chromosomal aberrations has been of interest. Thus far, however, studies have focused on frequencies of sperm with either abnormal morphology or aneuploidies in semen samples, not on detection of individual spermatozoa exhibiting both abnormal morphology and aneuploidy. To assess the feasibility of simultaneous evaluation of both attributes in an individual sperm cell, we investigated whether sperm shape is preserved after decondensation and denaturation, procedures that are required for fluorescent in situ hybridization (FISH). On 21 slides, 395 sperm were fixed, photographed, and then digitized by the computer-assisted Metamorph morphometry program for individual evaluation before decondensation. To establish whether sperm of various shapes would behave in similar manners, the cells were also classified, according to their head shapes, into symmetrical (n = 115), asymmetrical (n = 115), irregular (n = 115), and amorphous (n = 50) categories. Following decondensation and subsequent denaturation, sperm that had been photographed initially were relocalized and digitized for morphometry. Head area, perimeter, long axis, short axis, shape factor, and tail length were evaluated in each of the 395 sperm in both the native and decondensed states. After the decondensation and denaturation protocol of the FISH procedure, the sperm exhibited a proportional increase in dimensions as compared to their original sizes. Their initial shapes were preserved with high fidelity whether the sperm were in the symmetrical, asymmetrical, irregular, or amorphous categories. Hybridization with the chromosome probes had no further effect on sperm shape or size. We provide images to demonstrate how these findings facilitate studies about the relationship between sperm shape and chromosomal content or aberrations in individual spermatozoa. 相似文献
149.
150.