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31.
M. S. Al-Buriahi V. P. Singh Halil Arslan V. V. Awasarmol Baris T. Tonguc 《Radiation and environmental biophysics》2020,59(1):145-150
Mass attenuation coefficients ($$\mu _{\text {m}}$$) for some nonlinear optical materials such as potassium dihydrogen phosphate, ammonium dihydrogen phosphate, zinc tris-thiourea sulphate, and zinc thiourea chloride were measured using a $$2\times 2$$ NaI(Tl) scintillation detector at gamma energies of 122 keV, 356 keV, 511 keV, 662 keV, 840 keV, 1170 keV, 1270 keV, and 1330 keV. In addition, GEANT4 simulations were carried out to mimic the experiment at these energies. As a result, good agreement between the experimental and GEANT4 results was observed. The measured $$\mu _{\text {m}}$$ values were used to compute effective atomic numbers ($$Z_{\text {eff}}$$) for the selected materials. It was found that the $$Z_{\text {eff}}$$ values were in the range typical for dosimetric materials. 相似文献
32.
Sule Karadayi Sulhattin Arslan Zeynep Sumer Mustafa Turan Haldun Sumer Kursat Karadayi 《Molecular biology reports》2013,40(8):4701-4704
We hypothesized that solid tumors rarely occur in patients with hydatid disease. We obtained the serum of 14 patients diagnosed with hydatid disease, the serum of 10 patients who did not have a history of hydatid disease, and the hydatid cyst fluid from six patients. These sera and fluid samples were added at different concentrations to NCI-H209/An1 human lung small cell carcinoma cells and L929 mouse fibroblasts as a control group. Sera of patients with hydatid diseases had cytotoxic effects on NCI-H209/An1 cells, but they did not have cytotoxic effects on fibroblast cells. Sera from healthy subjects did not have a cytotoxic effect on the tumor cell line or control fibroblasts. Cyst fluid, also, did not have toxic effects on the NCI-H209/An1 cell line, but was toxic to fibroblasts up to a 1:32 dilution. Sera from patients with hydatid disease had cytotoxic effects on human small cell lung cancer cells in vitro. 相似文献
33.
Gungor Kanbak Kazım Kartkaya Eda Ozcelik Ahmet Burak Guvenal Sibel Canbaz Kabay Gul Arslan Ramazan Durmaz 《Gene》2013
Our aim in this study was to investigate the effect of moderate acute alcohol administration on cysteine protease mediated neuronal apoptosis and nitric oxide production in the traumatic brain injury. A total of 29 adult Sprague–Dawley male rats weighing 250–300 g were used. The rats were allocated into four groups. The first group was the control (sham-operated) group in which only a craniotomy was performed, the others were alcohol, trauma and trauma + alcohol groups. Caspase-3 enzyme activity in the trauma group increased significantly in comparison with the control group. The alcohol given group showed a decreased caspase-3 enzyme activity compared to the trauma group. The level of caspase-3 enzyme activity in the alcohol + trauma group decreased in comparison to the trauma group. SF/FEL ratio of cathepsin-L enzyme activity in the trauma group was significantly higher than in the control group. Our results indicate that moderate alcohol consumption may have protective effects on apoptotic cell death after traumatic brain injury. Protective effects of moderate ethanol consumption might be related to inhibition of lysosomal protease release and nitric oxide production. 相似文献
34.
Syed Ghulam Musharraf Arslan Ali Naik Tameem Khan Maria Yousuf Muhammad Iqbal Choudhary 《Steroids》2013,78(2):171-181
Electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to investigate the effect of different substitutions introduced during metabolism on fragmentation patterns of four anabolic steroids including methyltestosterone, methandrostenolone, cis-androsterone and adrenosterone, along with their metabolites. Collision-induced dissociation (CID) analysis was performed to correlate the major product ions of 19 steroids with structural features. The analysis is done to portray metabolic alteration, such as incorporation or reduction of double bonds, hydroxylations, and/or oxidation of hydroxyl moieties to keto functional group on steroidal skeleton which leads to drastically changed product ion spectra from the respective classes of steroids, therefore, making them difficult to identify. The comparative ESI-MS/MS study also revealed some characteristic peaks to differentiate different steroidal metabolites and can be useful for the unambiguous identification of anabolic steroids in biological fluid. Moreover, LC–ESI-MS/MS analysis of fermented extract of methyltestosterone, obtained by Macrophomina phaseolina was also investigated. 相似文献
35.
Jan Zima Atilla Arslan Petr Benda Miloš Macholán Boris Kryštufek 《Acta theriologica》2013,58(3):255-265
The study reports on chromosomes in several populations of social voles from south-eastern Europe and the Middle East. The standard karyotypes of individuals of Microtus hartingi and Microtus guentheri originating from both south-eastern Europe and Asia Minor comprised 54 mostly acrocentric chromosomes. However, variation between populations was found in the amount and distribution of C-heterochromatin in certain autosomes and the sex chromosomes. Furthermore, a specific pattern of argyrophilic nucleolar organizer region distribution was recorded in different geographic populations. In a population from Asia Minor, a heterozygous centric fusion of two autosomes was found. The G-banded karyotypes of M. guentheri and Microtus socialis were compared, and tandem fusions of autosomes were suggested as possible mechanism of the divergence. The karyotypes of the nine currently recognized species of social voles are reviewed, and implications of chromosomal data for systematics are evaluated. 相似文献
36.
A bioassay-guided phytochemical analysis of the triterpene saponins from under ground parts of Gypsophila arrostii var. nebulosa allowed the isolation of two triterpene saponins; nebuloside A, B based on gypsogenin and quillaic acid aglycone. Two new oleanane type triterpenoid saponins (nebuloside A, B) and three known saponins (1–3) were isolated from the root bark of Gypsophila arrostii var. nebulosa. The structures of the two new compounds were elucidated as 3-O-β-d-galactopyranosyl-(1→2)-[β-d-xylopyranosyl-(1→3)]-β-d-glucuronopyranosyl quillaic acid 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside A) and 3-O-β-d-xylopyranosyl-(1→3)-[β-d-galactopyranosyl(1→3)-β-d-galactopyranosyl-(1→2)]-β-d-glucuronopyranosyl gypsogenin 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside B), on the basis of extensive spectral analysis and chemical evidence. Nebuloside A and B showed toxicity enhancing properties on saporin a type-I RIP without causing toxicity by themselves at 15 μg/mL. 相似文献
37.
本文采用傅里叶变换红外光谱仪测定了四大种植主产区(安徽、江苏、福建、贵州)的栽培品及河南的野生品,共13个批次太子参甲醇提取物,获得不同产地太子参栽培品的FTIR指纹图谱,并对指纹图谱进行了相似度的计算,同时结合(共有峰率,变异峰率)双指标序列分析方法,对不同产地太子参的FTIR光谱进行了研究。结果表明,该方法所建立的太子参FTIR指纹图谱能够区分栽培品和野生品的差异,双指标序列分析法能够为产区间和产区内太子参品质差异提供参考,两种分析方法结合可为该药材的质量分析、评价与控制提供依据。 相似文献
38.
对2008年在甘肃省发生的一起疑似手足口病(HFMD)的发热出疹性疾病的流行进行病原体的实验室检测,明确引起这起传染病流行的病原体。从4名发热出疹患者采集的8份临床标本中(每个患者采集咽拭子和疱疹液标本),首先将临床标本接种到RD和HEp-2细胞上进行病毒分离,对病毒分离阳性的标本提取病毒核酸,然后使用荧光定量-逆转录-聚合酶链式反应(RT-PCR)进行人肠道病毒(HEV)核酸的检测。对HEV检测结果阴性的标本采用序列非依赖的单引物扩增技术(SISPA)进行"未知病原体"的鉴定。分离到的6株病毒均鉴定为单纯疱疹病毒I型(HSV-1),结合分析这起流行中患者的临床表现、流行病学调查结果以及实验室检测结果,表明HSV-1是引起这起发热出疹性疾病流行的病原体。6株HSV-1的gG区核苷酸和氨基酸水平上差异都较小,同源性分别高达98.8%和97.9%,说明这起疫情是由同一个病毒传播链引起的。HSV-1等病毒引起的发热出疹性疾病需要与HFMD进行鉴别诊断,由于仅从临床症状和流行病学资料上判断引起发热出疹性疾病的病原体是非常困难的,因此,必须依赖于实验室的诊断。 相似文献
39.
采用形态学观察和分子鉴定方法对2011年在陕西省发生的一种烟草未知病害的病原菌进行鉴定。从病叶组织分离纯化得到病原菌,通过致病性测定以及人工接种后再分离病菌,证明编号LJL007的菌株为该病的致病菌。依据病原菌的形态学和培养特征,将菌株LJL007鉴定为灰葡萄孢Botrytis cinerea Pers.,其有性型为富氏葡萄孢盘菌Botryotinia fuckeliana Whetzel。通过核糖体DNAITS序列分析,分离菌株LJL007序列(登录号:HM17900)与富氏葡萄孢盘菌序列(登录号:HM849615)同源性达100%,进一步证明该病原菌是灰葡萄孢Botrytis cinerea。云芝多糖在离体条件下,对灰葡萄孢的菌丝生长和孢子萌发均无直接抑制作用。云芝多糖对烟草灰霉病有较好预防保护作用,其预防效果可达56.29%。云芝多糖可显著提高烟草体内几丁质酶和β-1,3-葡聚糖酶活性,其活性峰值分别比对照提高56.89%和429.83%,说明云芝多糖可诱导植物产生抗病性。 相似文献
40.
目的:探讨激素联合丙种球蛋白治疗小儿重症肌无力的临床疗效及对患儿免疫球蛋白和补体的影响。方法:回顾性分析在我院治疗的70例重症肌无力患儿的临床资料,采用随机序号的方式将其分为观察组和对照组各35例,观察组给予甲泼尼龙联合丙种球蛋白,对照组仅给予甲泼尼龙,观察两组的临床疗效及免疫球蛋白和补体变化情况。结果:观察组总有效率为94.3%明显优于对照组74.3%,两组比较有统计学意义(P〈0.05);观察组症状明显缓解时间(6.55±1.35)d以及总住院天数(17.15±3.65)d较对照组明显缩短,两组比较差异均有统计学意义(P〈0.05)。结论:采用激素联合丙种球蛋白治疗小儿重症肌无力,可以明显改善患者肌无力症状,获得较为满意的临床疗效,值得进一步推广使用。 相似文献