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101.
102.
目的 对照血管内超声(intravascular ultrasound,IVUS)评价64层CT对冠状动脉粥样斑块的定性检测和定量分析。方法 2005年7月至10月连续纳入12例拟行PCI的稳定性心绞痛患者进行研究。所有患者术前接受64层CT的冠状动脉成像,术中行三支冠状动脉(左前降支、回旋支和右冠状动脉)的IVUS检查。结果 共对31支血管(左前降支12支,回旋支10支,右冠状动脉9支),88个节段进行了64层CT和IVUS的对比检查,其中64层CT可评价节段为68个。在IVUS检测到的51个有斑块节段中,64层CT检测出47个(敏感性92%),在17个IVUS判断为无斑块的节段中,64层CT判断16个为无斑块(特异性94%)。64层CT测量的斑块面积和IVUS测量的斑块面积相关(r=0.53,P〈0.01),但是高估了斑块面积[(9.09±3.89)mm。比(6.80±2.81)mm^2,P〈0.01]。64层CT在43个IVUS测定的低回声成分中检出30个为低密度成分,平均CT值67.39HU。结论 冠状动脉无严重钙化时,64层CT可准确检测冠状动脉近中段粥样斑块。64层CT测量的斑块面积虽然和IVUS测量结果相关,但准确测量受限。  相似文献   
103.
To clarify whether probucol and statins suppress oxidative stress in diabetic patients, we studied the effects of probucol and the statin atorvastatin on urinary 8-hydroxy-2'deoxyguanosine (8-OHdG) levels in diabetics with hypercholesterolemia. A randomized, open study was performed on a total of 36 patients with type 2 diabetes and hypercholesterolemia. The patients were randomly assigned to a probucol group (500 mg/day, n = 18) or an atorvastatin group (10 mg/day, n = 18). During three months, total- and LDL-cholesterol decreased significantly in both groups. LDL-cholesterol was significantly lower in the atorvastatin group than probucol group. HDL-C decreased significantly in the probucol group and did not change in the atorvastatin group. 8-OHdG decreased significantly in both groups after 3 months; 12.4 +/- 7.5 to 8.1 +/- 4.2 ng/mg/Cr in the atorvastatin group (p < 0.05) and 12.3 +/- 8.8 to 6.8 +/- 2.6 ng/mg/Cr in the probucol group (p < 0.05), and these changes did not differ significantly between the two groups. But, in patients with high 8-OHdG levels (more than 10 ng/mg/Cr) before administration, urinary 8-OHdG decreased significantly from 19.5 +/- 4.9 to 9.2 +/- 3.4 ng/mg Cr (p < 0.01) in the atorvastatin group, and from 19.7 +/- 8.2 to 6.67 +/- 2.2 ng/mg Cr (p < 0.01) in the probucol group. Urinary 8-OHdG was significantly lower in the probucol group than in the atorvastatin group after the second and third months of administration (p < 0.05). These results suggest that while probucol and atorvastatin both reduce systemic oxidative stress, probucol might be the more useful in patients with strong oxidative stress.  相似文献   
104.
The effects of methamphetamine (MAP) administration on neurotensin-like immunoreactivity (NTLI) were investigated in the rat brain. A single administration of MAP induced dose-dependent and reversible increases in NTLI in the caudate-putamen, limbic forebrain and midbrain. NTLI in the caudate-putamen, limbic forebrain and midbrain was also enhanced after repeated administration of MAP. It was assumed that MAP enhanced NTLI in the caudate-putamem, limbic forebrain and midbrain through its action upon the nigrostriatal and mesolimbic dopamine systems.  相似文献   
105.
We report on a patient who developed acute rhabdomyolysis after taking cerivastatin. A 74-year-old hypercholestrerolaemic woman taking cerivastatin (0.15 mg/day) for 22 days complained of general muscle weakness and muscle pain. Her serum creatinine phosphokinase level was 19,190 IU/L. Serum myoglobin was over 3000 ng/mL. Serum concentration of cerivastatin at 6 h after taking the last dose (0.15 mg) was 8062.5 ng/L, which was almost 5.7 times higher than that of normal persons. The serum concentration of cerivastatin showed that the half-life of cerivastatin in this patient was 22.4 h, compared with 2.4 h for normal controls. Cerivastatin is catabolized by cytochrome P450, 3A4 and 2C8 to M-1, and by 2C8 to M-23. The ratio of M-23 to M-1 in her serum was much lower than that of control persons (0.64 vs. 2.08). She had previously taken simvastatin which is metabolized by CYP3A4, without any sign and symptoms of rhabdomyolysis. These results suggest that the slowed clearance of cerivastatin in this patient might have been compounded by cytochrome P450, 2C8 dysfunction.  相似文献   
106.
BACKGROUND AND PURPOSE: Diffusion tensor imaging (DTI) was introduced as a good technique to evaluate structural abnormalities in the white matter. In this study, we used DTI to examine anisotropic changes of the pyramidal tracts displaced by chronic subdural hematoma (CSDH).MATERIALS AND METHODS: Twenty-six patients with unilateral CSDH underwent DTI before and after surgery. We measured fractional anisotropy (FA) values in pyramidal tracts of bilateral cerebral peduncles and calculated the ratio of the FA value on the lesion side to that on the contralateral side (FA ratio) and compared the ratios with motor weakness. Moreover, the relationships between FA ratios and clinical factors such as age, sex, midline shift, interval from trauma, and hematoma attenuation on CT were evaluated.RESULTS: FA values of pyramidal tracts on the lesion side were significantly lower than those on the contralateral side (0.66 ± 0.07 versus 0.74 ± 0.05, P < .0001). The FA ratio was correlated to the severity of motor weakness (r2 = 0.32, P = .002). FA ratios after surgery improved significantly compared with those before surgery (0.96 ± 0.08 versus 0.89 ± 0.07, P = .0004). Intervals from trauma and the midline shift were significantly associated with decreased FA ratios (P = .0008 and P = .037).CONCLUSIONS: In patients with CSDH, a reversible decrease of FA in the affected pyramidal tract on DTI was correlated to motor weakness. These anisotropic changes were considered to be caused by a reversible distortion of neuron fibers and vasogenic edema due to the hematoma.

Chronic subdural hematoma (CSDH) is a progressive space-occupying lesion, which may lead to reversible reduction in cerebral function due to brain compression or brain displacement. The causes, clinical characteristics, and therapeutic management of CSDH are well established; however, the detailed physiology, including the mechanisms of appearance with motor dysfunction in patients, is still controversial.14Diffusion tensor imaging (DTI) reveals the tissue microstructure and architecture of white matter tracts, including pyramidal tracts, and extracts the principal diffusivities, mean diffusivities (MD), and fractional anisotropy (FA). Previously, it was reported that decreased FA in the pyramidal tracts on DTI was associated with secondary degeneration and could be a reliable measure of motor weakness.58 The purpose of this study was to investigate changes of DTI in affected pyramidal tracts of patients with CSDH and to evaluate the association between changes of FA and clinical factors such as age, sex, hematoma thickness, midline shift, interval from the trauma, and attenuation on CT.  相似文献   
107.
108.
Aims/IntroductionWe investigated the association between gestational diabetes mellitus (GDM) and perinatal outcomes stratified by pre‐pregnancy body mass index (BMI) and/or gestational weight gain (GWG).Materials and MethodsData from the national birth cohort in the Japan Environment and Children''s Study from 2011 to 2014 (n = 85,228) were used. Japan uses the GDM guidelines of the International Association of Diabetes and Pregnancy Study Groups. The odds ratios (ORs) of perinatal outcomes were compared between women with and those without GDM.ResultsThe OR (95% confidence interval) of having a small for gestational age infant in the GDM group with a pre‐pregnancy BMI of ≥25.0 kg/m2 and insufficient GWG (<2.75 kg) was 1.78 (1.02–3.12). The OR of having a large for gestational age infant of the same BMI group with excessive GWG (>7.25 kg) was 2.04 (1.56–2.67). The OR of hypertensive disorders of pregnancy was higher in women with a BMI ≥18.5 kg/m2 in the GDM group than in the non‐GDM group.ConclusionsLarge for gestational age and hypertensive disorders of pregnancy were associated with pre‐pregnancy BMI and GWG in either normal weight or overweight/obese women, and the relationship was strengthened when GDM was present. Women with GDM and a BMI of ≥25.0 kg/m2 are at risk of having small for gestational age and large for gestational age infants depending on GWG.  相似文献   
109.
Pathogenesis of idiopathic scoliosis. Experimental study in rats.   总被引:19,自引:0,他引:19  
M Machida  I Murai  Y Miyashita  J Dubousset  T Yamada  J Kimura 《Spine》1999,24(19):1985-1989
STUDY DESIGN: A radiographic examination of pinealectomized rats to observe the development of scoliosis and halt the condition by administration of melatonin. OBJECTIVES: To discover whether pinealectomy has the same effect in mammals as shown in the chicken, and to determine whether the bipedal condition is important for development of scoliosis. SUMMARY OF BACKGROUND DATA: Pinealectomizing chickens shortly after hatching consistently resulted in scoliosis closely resembling human idiopathic scoliosis. It has not been determined whether this phenomenon is restricted solely to chickens, or if this experimental model is applicable to other animals, especially those more closely related to humans. METHODS: A sham operation in five bipedal rats served as the control in this study. Pinealectomy was performed in 10 quadrupedal rats, pinealectomy in 20 bipedal rats, and pinealectomy with implantation of melatonin pellet in 10 bipedal rats. Spinal radiographs were used to measure the degree of scoliosis at 3 months after surgery. RESULTS: Scoliosis developed only in pinealectomized bipedal rats and not in quadrupedal rats. It developed in none of the sham operation group and in only 1 of 10 pinealectomized bipedal rats with melatonin treatment. CONCLUSIONS: Melatonin deficiency secondary to pinealectomy alone does not produce scoliosis if the quadrupedal condition is maintained. The bipedal condition, such as that in chickens or humans, plays an important role in the development of scoliosis. The findings suggest a critical influence of a postural mechanism for the development of scoliosis.  相似文献   
110.
It is known that the temporal cortex is involved in perception of emotional facial expressions, and the involvement is relatively independent of the emotional valence of those expressions. The present study revealed a valence-dependent aspect of the temporal cortex through individual differences analyses involving the neuroticism trait, one of the representative affective personality traits. Functional MRI was administered while subjects classified expressions of faces, and neuroticism scores were obtained from individual subjects. Significant brain activity was observed in the temporal pole (TP) during perception of both happy and sad expressions relative to neutral expressions. Correlational analyses revealed that TP activity during perception of sad expressions, but not happy expressions, correlated with the neuroticism scores. These results demonstrate differential roles for the temporal cortex in perception of happy and sad faces, and suggest that TP recruitment during understanding of negative emotions is dependent on the personality of the individuals.  相似文献   
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