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排序方式: 共有368条查询结果,搜索用时 15 毫秒
81.
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
82.
83.
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
84.
Narayanasamy Angayarkanni Radhakrishnan Selvi Rishi Pukhraj Jyotirmoy Biswas Shah J. Bhavesh Joyce Tombran-Tink 《Journal of ocular biology, diseases, and informatics》2009,2(1):20-28
Eales disease (ED) is an idiopathic inflammatory venous occlusion of the peripheral retina. As neovascularization is prominent in ED, this study attempts to look at the ratio of VEGF, the angiogenic factor, and PEDF, an anti-angiogenic factor in the vitreous of ED patients in comparison with the macular hole (MH) and Proliferative Diabetic Retinopathy (PDR). Vitreous levels of VEGF and PEDF were determined in the undiluted vitreous specimen obtained from 26 ED cases, 17 PDR, and seven patients with MH. The vitreous levels of VEGF and PEDF were estimated by ELISA. The immunohistochemistry (IHC) for VEGF and PEDF were done in the epiretinal membrane of ED and PDR case. The VEGF/PEDF ratio was found to be significantly increased in ED (p = 0.014) and PDR (p = 0.000) compared to MH. However the ratio was 3.5-fold higher in PDR than ED (p = 0.009). The IHC data on the ERM specimen from ED showed the presence of VEGF and PEDF similar to PDR. The high angiogenic potential seen as the ratio of VEGF/PEDF correlates with the peak clinical onset of the disease in the age group 21–30 years and the diseases usually self-resolves above the age of 40, which is reflected by the low ratio of VEGF/PEDF. The study shows that the VEGF/PEDF ratio is significantly increased in ED though the angiogenic potential is higher in PDR than in ED. Clinically Eales Disease is known as a self-limiting disease, while PDR is a progressive disease. 相似文献
85.
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
86.
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
87.
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
88.
Bone-targeted 2,6,9-trisubstituted purines: novel inhibitors of Src tyrosine kinase for the treatment of bone diseases 总被引:2,自引:0,他引:2
Wang Y Metcalf CA Shakespeare WC Sundaramoorthi R Keenan TP Bohacek RS van Schravendijk MR Violette SM Narula SS Dalgarno DC Haraldson C Keats J Liou S Mani U Pradeepan S Ram M Adams S Weigele M Sawyer TK 《Bioorganic & medicinal chemistry letters》2003,13(18):3067-3070
Novel bone-targeted 2,6,9-trisubstituted purine template-based inhibitors of Src tyrosine kinase are described. Drug design studies of known purine compounds revealed that both positions-2 and -6 were suitable for incorporating bone-seeking moieties. A variety of bone-targeting groups with different affinity to hydroxyapatite were utilized in the study. Compound 3d was determined to be a potent Src inhibitor and was quite selective against a panel of other protein kinases. 相似文献
89.
Kozlowski PA Williams SB Lynch RM Flanigan TP Patterson RR Cu-Uvin S Neutra MR 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(1):566-574
A cholera vaccine containing killed vibrios and cholera toxin B subunit (CTB) was used to compare mucosal immunization routes for induction of systemic and mucosal Ab. Four groups of women were given three monthly immunizations by the rectal immunization (R(imm)) route, nasal immunization (N(imm)) route, or vaginal immunization route during either the follicular (V-FP(imm)) or luteal (V-LP(imm)) menstrual cycle phase. N(imm) was performed with 10-fold less vaccine to determine if administration of less Ag by this route can, as in rodents, produce mucosal Ab responses comparable to those induced by higher dose R(imm) or vaginal immunization. Concentrations of Ab induced in sera and secretions were measured by ELISA. None of these routes produced durable salivary Ab responses. N(imm) induced greatest levels of CTB-specific IgG in sera. R(imm) failed to generate CTB-specific IgA in genital tract secretions. N(imm), V-FP(imm), and V-LP(imm) all produced cervical CTB-specific IgA responses comparable in magnitude and frequency. However, only V-FP(imm) induced cervical IgA2-restricted Ab to the bacterial LPS vaccine component. V-FP(imm), but not V-LP(imm), also induced CTB-specific IgA in rectal secretions. N(imm) was superior to V-FP(imm) for producing rectal CTB-specific IgA, but the greatest amounts of CTB-specific IgA and LPS-specific IgA, IgG, and IgM Ab were found in rectal secretions of R(imm) women. These data suggest that in women, N(imm) alone could induce specific Ab in serum, the genital tract, and rectum. However, induction of genital tract and rectal Ab responses of the magnitude generated by local V-FP(imm) or R(imm) will likely require administration of comparably high nasal vaccine dosages. 相似文献
90.