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991.
p-Methylselenostyrene ( 1 ) and p-phenylselenostyrene ( 2 ) as selenium-containing vinyl monomers were prepared. Both monomers are readily polymerized free radically to afford the corresponding polymers having molecular weight of about 20 000 ∼ 150 000. These homopolymers are stable below 300°C. From the copolymerization with styrene, Q values of 1 and 2 were calculated to be 1,18 and 1,03, respectively. On the other hand, e values of these monomers are −0,24 and −0,04, respectively, indicating the electron withdrawing character of the seleno groups.  相似文献   
992.
目的 评价自动定量分析法(automated quantitative analysis,AQUA)测定表皮生长因子受体(epidermal growth factor receptor,EGFR)在口咽部鳞状细胞癌组织中的表达水平,了解其在判定预后中的价值.方法 AQUA系统分析了一个由95例口咽癌石蜡标本组成的组织微阵列中EGFR的表达,并进行临床和组织病理学资料的相关性分析,将细胞角蛋白(cytokeratin)设为标志物,将数码相机自动拍摄的显示其表达强度的图像载入自动分析系统,设定了每个微阵列点的肿瘤范围,同时用荧光色素原Cy5的耦连抗体显示靶抗原EGFR,并自动计算EGFR表达的像素密度,将其表达数字化,这样就产生了一个数字化的连续变量,它与单位面积内阳性表达的靶抗原分子数量成正比.按表达变量的中位数划分其表达强弱,分成高、低表达组.结果 ①5年局部复发率,肿瘤组织中EGFR细胞高表达组为57.8%,而低表达组为17.2%,相比有显著的统计学意义(P<0.01);在肿瘤组织中EGFR细胞核高表达组的5年局部复发率为54.4%,低表达组为21.4%,相比也有统计学意义(P<0.05);②在5年无瘤生存率方面,EGFR肿瘤细胞高表达组(19.0%)及细胞核高表达组(19.0%),分别与细胞低表达组(43.4%)和细胞核低表达组(44.8%)相比也有显著的统计学差异(P均<0.05);③多变量风险回归分析,肿瘤细胞和细胞核EGFR高表达都是一个独立的预后负相关因子,有统计学意义.结论 AQUA系统可以有效地对石蜡组织切片中EGFR的表达进行连续变量分析,揭示了EGFR的表达与其产生的生物学作用的联系,EGFR的AQUA数值有望成为能预测EGFR靶向治疗敏感性的一个生物学指标.  相似文献   
993.
ContextThe bulb of Lilium brownii F. E. Brown (Liliaceae) (LB) is a common Chinese medicine to relieve insomnia.ObjectiveTo investigate the molecular mechanism of LB relieving insomnia.Materials and methodsInsomnia model was induced by intraperitoneally injection p-chlorophenylalanine (PCPA) in Wistar rats. Rats were divided into three groups: Control, PCPA (400 mg/kg, i.p. 2 days), LB (598.64 mg/kg, oral 7 days). The levels of 5-hydroxytryptamine (5-HT), norepinephrine (NE), melatonin (MT), and the expression of GABAA, 5-HT1A and MT receptors, as well as pathological changes in hypothalamus, were evaluated. 16S rDNA sequencing and UPLC-MS/MS were used to reveal the change of the intestinal flora and metabolic profile.ResultsThe adverse changes in the abundance and diversity of intestinal flora and faecal metabolic phenotype altered by PCPA in rats were reversed after LB treatment, accompanied by the up-regulated levels of 5-HT as 8.14 ng/mL, MT as 16.16 pg/mL, 5-HT1A R and GABAA R, down-regulated level of NE as 0.47 ng/mL, and the improvement of pathological phenomena of cells in the hypothalamus. And the arachidonic acid metabolism and tryptophan metabolism pathway most significantly altered by PCPA were markedly regulated by LB. Besides, it was also found that LB reduced the levels of kynurenic acid related to psychiatric disorders and trimethylamine-N-oxide associated with cardiovascular disease.ConclusionThe mechanism of LB relieving insomnia involves regulating flora and metabolites to resemble the control group. As a medicinal and edible herb, LB could be considered for development as a health-care food to relieve increasing insomniacs in the future.  相似文献   
994.
目的 探讨血脂水平与中老年人偏头痛的相关性,分析其对偏头痛的诊断的临床意义.方法 选取41例偏头痛患者为实验组,46例健康体检者为对照组.采用标准酶促法测定实验组和对照组的血清中的TC、TG、LDL-C的水平,并进行统计分析.结果 偏头痛组TC、LDL-C水平与对照组相比无统计学差异,偏头痛组TG水平与对照组相比差异有...  相似文献   
995.
Causative agent identification is important in the treatment of poisoning. We report the case of a patient who presented with an altered level of consciousness after drinking a fluorescent pink liquid. Upon measuring the anion gap and urinary calcium oxalate level, the patient was diagnosed with early ethylene glycol poisoning.  相似文献   
996.
Background: Invasive pneumococcal disease (IPD) is an infectious disease where Streptococcus pneumoniae can be detected in the cerebrospinal fluid or blood.Methods: Eight patients presented to our hospital with adult IPD. We compared with 69 cases of pneumococcal pneumonia treated in our department between 2012 and 2014. None of the patients had a history of pneumococcal vaccine administration.Results: Hematological examination showed the platelet count was significantly lower and the serum C-reactive protein level was significantly higher in the IPD group. There was a significant difference in the use of a respirator and mortality in the IPD group. About antibiotics, Carbapenem and quinolone were used for the treatment of many patients in the IPD group. In the fatal three cases of IPD, the age of all members were 65 years or younger. Two of three had no underlying disease.Conclusion: IPD develops without elderly people and in those without underlying disease. Also, the patients who took a sudden course may result in death. In line with previous studies that have reported the effectiveness of the pneumococcal vaccine, our study findings emphasize the need of administering vaccination for prevention of IPD in person who was younger than 65 years old.  相似文献   
997.
PurposeNon-calcified cholesterol stones that are small in size are hard to be depicted on CT or magnetic resonance cholangiopancreatography. This institutional review board (IRB)-approved retrospective in vitro study aims to characterize contrast behaviors of 3 main components of the gallstones, i.e., cholesterol component (CC), bilirubin calcium component (BC) and CaCO3 (CO) on 3D radial scan with ultrashort TE (UTE) MRI, and to test the capability of depicting CC of gallstones as bright signals as compared to background saline.MethodsFourteen representative gallstones from 14 patients, including 15 CC, 6 BC and 4 CO, were enrolled. The gallstones underwent MRI including fat-saturated T1-weighted image (fs-T1WI) and UTE MRI with dual echoes. The contrast-to-noise ratio (CNR) and the chemical analysis for the 25 portions of the stones were compared.ResultsBC was bright on fs-T1WI, which did not change dramatically on UTE MRI and the signal did not remain on UTE subtraction image between dual echoes. Whereas the CC was negative or faintly positive signal on fs-T1WI, bright signal on UTE MRI and the contrast remained even higher on the UTE subtraction, which reflected their short T2 values. Median CNRs and standard errors of the segments on each imaging were as follows: on fs-T1WI, −10.2 ± 4.2 for CC, 149.7 ± 27.6 for BC and 37.9 ± 14.3 for CO; on UTE MRI first echo, 16.7 ± 3.3 for CC, 74.9 ± 21.3 for BC and 17.7 ± 8.4 for CO; on UTE subtraction image, 30.2 ±2.0 for CC, −11.2 ± 5.4 for BC and 17.8 ± 10.7 for CO. Linear correlations between CNRs and cholesterol concentrations were observed on fs-T1WI with r = −0.885, (P < 0.0001), UTE MRI first echo r = −0.524 (P = 0.0072) and UTE subtraction with r = 0.598 (P = 0.0016).ConclusionUTE MRI and UTE subtraction can depict CC bright.  相似文献   
998.
999.
1000.
Maintenance of the cluster of differentiation 4 (CD4) positive lymphocyte count (CD4 count) is important for human immunodeficiency virus (HIV) positive individuals. Although a higher body mass index (BMI) is shown to be associated with a higher CD4 count, BMI itself does not reflect body composition. Therefore, we examined the association of body weight, body composition and the CD4 count, and determined the optimal ranges of CD4 count associated factors in Japanese HIV positive individuals. This cross-sectional study included 338 male patients treated with antiretroviral therapy for ≥12 months. Multiple logistic regression analysis was used to identify factors significantly associated with a CD4 count of ≥500 cells (mm3)−1. The cutoff values of factors for a CD4 ≥ 500 cells (mm3)−1 and cardiovascular disease risk were obtained by receiver operating characteristic curves. Age, body fat percentage (BF%), nadir CD4 count, duration of antiretroviral therapy (ART), years since the HIV-positive diagnosis and cholesterol intake showed significant associations with the CD4 count. The cutoff value of BF% for a CD4 ≥ 500 cells (mm3)−1 and lower cardiovascular disease risk were ≥25.1% and ≤25.5%, respectively. The BF%, but not the BMI, was associated with CD4 count. For the management of HIV positive individuals, 25% appears to be the optimal BF% when considering the balance between CD4 count management and cardiovascular disease risk.  相似文献   
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