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51.
The aim of this research was to assess whether common genetic variants within the C-reactive protein gene ( CRP ) are related to the degree of acute rise in plasma C-reactive protein (CRP) levels following an acute coronary syndrome (ACS). While polymorphisms within CRP are associated with basal CRP levels in healthy men and women, less is known about the relationship of such genetic variants and the degree of CRP rise during and after acute ischemia. Plasma CRP is associated with increased rates of recurrent coronary events. We evaluated seven common genetic variants within CRP and assessed their relationship to the degree of rise in CRP levels immediately following an acute coronary syndrome in 1827 European American patients. Variants in the putative promoter region, −757T > C and −286C > T > A, were associated with the highest CRP elevations after ACS. Patients with two copies of the A allele of SNP −286C > T > A had median CRP values of 76.6 mg/L, compared to 11.1 mg/L in patients with no copies of the rare variant (p-value <0.0001), post ACS. The lowest CRP values were found for patients with minor alleles of the exonic 1059G > C and the 3'untranslated region 1846G > A SNPs. For example, patients homozygous for the minor allele of 1059G > C had 71% lower median CRP values than those homozygous for the major allele [3.5 vs 12.0 mg/L, p < 0.0001]. These trends persisted in the chronic stable phase after ischemia had resolved, and after adjustment for infarct size by peak creatinine kinase levels and clinical status by Killip class. Assessment of CRP genetic variants identified patients with higher and lower CRP elevation after acute coronary syndrome.  相似文献   
52.
A rehabilitation program including foot sensory stimulation, balance and gait training with limited vision was performed in 24 patients with clinically defined sensory ataxia. There were 15 patients with bilateral somatosensory loss related to chronic neuropathy and nine patients with unilateral loss-related to multiple sclerosis. After training, balance control assessed using the Berg Balance Test improved similarly in both groups, and Romberg's sign disappeared in some patients, suggesting an improvement in dynamic balance and in the proprioceptive contribution. Conversely, balance assessed on a static force platform remained similar in the open-eyes condition and improved in the closed-eyes condition only in patients with unilateral sensory loss. These results show that ataxic patients can improve their balance with better results in dynamic conditions and that the relative contribution of proprioceptive and visual inputs may depend on the extent of somatosensory loss.  相似文献   
53.
m.  fox    r.  sweis    t.  wong  † & a.  anggiansah 《Neurogastroenterology and motility》2007,19(10):798-803
Oesophageal spasm presents with dysphagia and chest pain. Current treatments are limited by poor efficacy and side effects. Studies in health and oesophageal dysmotility show that sildenafil reduces peristaltic pressure and velocity; however the clinical efficacy and tolerability in symptomatic oesophageal spasm remains uncertain. We provided open-label sildenafil treatment to two patients with severe, treatment resistant symptoms associated with oesophageal spasm. The effects of sildenafil on oesophageal function and symptoms were documented by high resolution manometry (HRM). Patients were followed up to assess the efficacy of maintenance treatment with sildenafil b.i.d. HRM revealed focal and diffuse spasm in the smooth muscle oesophagus that were associated with symptoms in both cases, especially on swallowing solids. Lower oesophageal sphincter function was normal. A therapeutic trial of 25-50 mg sildenafil suppressed oesophageal contraction almost completely for water swallows; however effective, coordinated peristalsis returned with reduced frequency of spasm for solid swallows. Dysphagia and chest pain resolved during the therapeutic trial and efficacy was maintained on maintenance treatment with 25-50 mg sildenafil b.i.d. without troublesome side effects. This report shows that sildenafil can improve oesophageal function and relieve dysphagia and chest pain in patients with oesophageal spasm in whom other treatments have failed.  相似文献   
54.
Limited spatial resolution is a key obstacle to the study of brain white matter structure with diffusion tensor imaging (DTI). In its frequent implementation with single-excitation spin-echo echo-planar sequences, DTI's ability to resolve small structures is strongly restricted by T2 and T2* decay, B0 inhomogeneity, and limited signal-to-noise ratio (SNR). In this work the influence of sensitivity encoding (SENSE) on diffusion-weighted (DW) image properties is investigated. Computer simulations showed that the PSF becomes narrower with increasing SENSE reduction factors, R, enhancing the intrinsic resolution. After a brief theoretical discussion, we describe the estimation of SNR on a pixel-by-pixel basis as a function of R. The mean image SNR behavior is manifold: SENSE is capable of increasing SNR efficiency by reducing the echo time (TE). Each SNR(R) curve reveals a maximum that depends on the amount of partial Fourier encoding used. The overall best SNR efficiency for an eight-element head coil array and a b-factor of 1000 s/mm2 is achieved at R = 2.1 and partial Fourier encoding of 60%. In vivo tensor maps of volunteers and a patient, with an in-plane resolution of 0.78 x 0.78 mm2, are also presented to demonstrate the practical implementation of the parallel approach.  相似文献   
55.
稳定性核素测定大鼠小肠蛋白质合成   总被引:2,自引:1,他引:1  
目的:建立稳定性核素([L-^15N]亮氨酸)测定大鼠小肠蛋白质合成率的方法。方法:分别测定静脉注射相同剂量[L-^15N]亮氨酸不同时相的大鼠小肠^15N丰度及不同剂量[L-^15N]亮氨酸同一时相的大鼠小肠^15N丰度。结果:大鼠小肠游离氨基酸池中^15N核素丰度在注射后0.5h内呈线性上升并达高峰,维持4h后缓慢下降,小肠蛋白质中的^15N丰度0.5h至12h基本维持不变;随着注射剂量的增加,大鼠小肠蛋白质分数合成率(FSR)亦增加,当[L-^15N]亮氨酸剂量在1.0mmol/kg以上,FSR并不随施加[L15N]亮氨酸剂量的加大而增加。结论:在进行大鼠小肠蛋白质合成率测定时,一次性静脉注射的测量最佳时限为0.5h,剂量为1.0mmol/kg。  相似文献   
56.
目的观察卡维地洛对不稳定型心绞痛(UAP)患者高敏C反应蛋白(hs-CRP)、白介素-6(IL-6)及细胞间可溶性黏附分子1(sICAM-1)水平的影响。方法UAP患者62例采用完全随机化方法分成对照组(n=30)和治疗组(n=32),在常规抗血小板、扩血管治疗基础上,对照组予美托洛尔(12.5mg,2次/d×3d)口服,治疗组服卡维地洛(6.25mg,2次/d×3d),在治疗前后分别测定hs-CRP、IL-6、sICAM-1值。结果对照组和治疗组在治疗前hs-CRP、IL-6、sICAM-1均无显著性差异;用药后两组3指标均较用药前显著降低(P<0.05);治疗组在用药后IL-6、sI-CAM-1显著低于对照组(P<0.05)。同时,用药后两组患者的心率、血压、心肌耗氧量均较用药前显著降低(P<0.05),治疗组的心肌耗氧量显著低于对照组(P<0.05)。结论卡维地洛可显著降低UAP患者的炎症因子IL-6、sICMA-1水平。  相似文献   
57.
The role of intracellular Zn2+ in the translocation of protein kinase C from cytosol to membrane fractions was examined by the [3H]phorbol 12,13-dibutyrate (PDBu) binding method in guinea pig cerebral synaptoneurosomes. N-methyl-d-aspartate (NMDA, 100 μM) and calcium ionophore A23187 (0.3–30 μM) decreased the binding activity in the cytosol with a concomitant increase in the membrane fractions. Pretreatment of synaptoneurosomes with a heavy metal chelator, N,N,N′,N′-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN), inhibited the NMDA- and A23187-induced changes of the distribution of [3H]PDBu binding sites in cytosol and membrane fractions. The inhibitory effect of TPEN was negated by a preincubation of TPEN with equimolar Zn2+ but not by that with Ca2+. The addition of 500 μM Zn2+ to the lysate of synaptoneurosomes induced an increase of [3H]PDBu binding activity in the membrane fraction with a concomitant decrease in the cytosol fraction, as did 100 μM Ca2+. Low concentrations of Zn2+ (10 μM), which alone had no effect on the distribution of the binding, significantly enhanced the effect of 10 μM Ca2+ in the lysate. Under those conditions TPEN inhibited the Zn2+-potentiated Ca2+-dependent changes in the binding. These results suggest that intracellular Zn2+ is essential for the agonist-induced translocation of protein kinase C in guinea pig synaptoneurosomes.  相似文献   
58.
Abstract: Precise determination of the peptide content in drug substance samples depends highly upon the particular peptide compound and methodology used. Four independent methods were evaluated and compared to determine which would produce the best experimental precision for analysis of thymalfasin (thymosin α‐1). Four different methods were evaluated including elemental analysis (CHN), quantitative amino acid analysis (AAA), high‐performance liquid chromatography (HPLC), and Kjeldahl. This study demonstrates that the AAA method is highly variable in one laboratory while quite precise in another laboratory. Similarly, HPLC results depended on the laboratory conducting the study with more precise values obtained under cGMP. On the contrary, the CHN method yielded highly precise [i.e. <2% coefficient of variation (CV)] values. As precise knowledge of protein content is fundamental for the compounding of final pharmaceutical product of a specific potency, the CHN analysis is recommended for peptide content determination of the drug substance thymalfasin.  相似文献   
59.
目的:探讨survivin反义寡核苷酸(ASODN)对人肝癌细胞HepG2的抑制作用。方法:采用免疫组织化学法检测肝细胞癌(HCC)组织中survivin的表达。采用脂质体介导survivin ASODN体外转染人肝癌细胞株HepG2,Western blot检测细胞survivin蛋白的表达,FCM检测细胞的凋亡率,观察细胞在软琼脂中的集落形成能力。建立人肝癌裸鼠皮下移植瘤模型,观察survivin ASODN的体内抑癌作用。 结果:(1)肝癌组织中survivin表达阳性率为75.8%(25/33),明显高于癌旁组织和正常肝组织(P<0.01);(2)survivin ASODN体外转染可明显下调HepG2细胞survivin蛋白表达,ASODN组HepG2细胞凋亡率明显高于空白对照组和SODN组(P<0.01),ASODN组HepG2细胞在软琼脂中形成的集落数目明显少于空白对照组和SODN组(P<0.01);(3)ASODN组瘤体生长速度较空白对照组和SODN组明显减慢(P<0.01),ASODN组瘤体重量较空白对照组和SODN组明显减轻(P<0.05)。结论:Survivin在HCC组织中高表达;survivin ASODN可以诱导HepG2细胞凋亡,在体外实验和动物实验中对HepG2细胞生长都有抑制作用。  相似文献   
60.
血管内皮生长因子在高原脑水肿形成中作用的实验研究   总被引:4,自引:0,他引:4  
目的:探讨血管内皮生长因子(VEGF)在高原脑水肿形成中的作用。方法:建立大鼠模拟高原模型,应用脑干湿重比率法定量脑水肿情况、应用荧光素钠透过率测定BBB通透性、应用实时荧光定量RT-PCR法检测脑组织VEGF mRNA含量以及应用蛋白印迹法半定量脑组织VEGF含量。结果:大鼠在高原24 h后脑组织含水率明显增高(P<0.05),荧光素钠透过率显著增加(P<0.01);VEGF mRNA转录及其表达显著增高(P<0.001)。结论:VEGF表达在高原脑水肿形成中起重要作用。  相似文献   
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