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101.
慢性肾病(chronic kidney disease,CKD)可引起肠道菌群失调及肠道屏障功能受损,而肠道稳态的破坏有
利于肠源性毒素的产生及肠腔细菌、内毒素的易位,加重CKD的尿毒症毒性及全身性炎症。膳食纤维可靶向作用于
“肠-肾轴”,从而降低CKD的尿毒症毒素水平及减轻全身性炎症。膳食纤维有望成为治疗CKD的新策略。 相似文献
102.
医用显微图像处理系统的研制和软件开发 总被引:1,自引:1,他引:0
目的 建立医用显微图像处理系统。方法 用普通光学显微镜、工业用摄像机、视频卡和计算朵等构成硬件系统,用VC++5.0和微软基础类库(Microsoft Function Class,MFC)开发了显微图像处理的专用类CDIB,并结合数据库系统,完成了外周血白细胞分类诊断系统。结果 应用该系统对130例病人进行白细胞分类与人工镜检对比,两者结果相符合。结论 该系统具有很好的实用价值和推广价值,可广泛 相似文献
103.
In sheep cardiac Purkinje fibers concentration-dependent inhibition of transient outward current (ito) by 4-aminopyridine (4-AP, 3-1000 mol/l) was recorded with the two-microelectrode voltage-clamp technique, and correlated effects on action potential duration measured at — 70 mV (APD-70) were investigatigated.Half-maximal inhibition of ito-amplitude occurred at 15 mol/l 4-AP. The drug exhibited no major effect on voltage-dependent control of inactivation but reduced the maximally available ito-current. At different activation frequencies (0.05 Hz, 0.25 Hz, 1 Hz) an equal amount of ito-current, measured as percentage of the respective control, was inhibited by 4-AP. The APD-70 was on the average increased by 4-AP (3–500 mol/l) in a concentration-dependont manner up to 151 % of control. The drug-induced prolongation, measured as percentage of the respective control, was independent of stimulation frequency (0.05 Hz, 0.25 Hz, 1 Hz). Prolongation of APD-70 was on the average more pronounced for short action potentials (APD-70<150 ms: 169 % of reference) than for longer ones (APD-70 150–300 ms: prolongation to 117 % of reference; 500 mol/l 4-AP; 0.25 Hz stimulation rate). Few long control signals (APD-70 >300 ms) were shortened by 4-AP. These results indicate that inhibition of ito-current by appropriate drugs will result in a reduction of inhomogeneity of action potential duration. 相似文献
104.
We carried out a morphometric study on the myelinated fibers in the anterolateral funiculus (ALF) and lateral corticospinal tract (LCS) in the cervical segment of the spinal cord of 13 patients with classic amyotrophic lateral sclerosis (ALS), 6 of whom had been on a respirator: 5 age-matched subjects were used as controls. The results obtained revealed that: (1) the fiber-size distributions of the myelinated fibers in the ALF and LCS of the control subjects had peaks at 2 m; (2) there were marked and significant losses of large myelinated fibers in the ALF and LCS of ALS patients; (3) the patients who required respirator support showed more severe degeneration in the ALF than those who required none; and (4) the degree of myelinated fiber loss in the LCS did not correlate with either the illness duration or the history of respirator use. 相似文献
105.
106.
《Seminars in perinatology》2022,46(5):151591
The objective of this chapter is to trace the evolution of intraventricular hemorrhage in the premature infant highlighting the importance of the germinal matrix, a critical role for cerebral blood flow changes in the genesis of hemorrhage, clinical factors that increase the bleeding risk, and potential preventative strategies. In 1976, neuropathological studies demonstrated capillary rupture within the germinal matrix as the precursor of hemorrhage. In 1980, introduction of cranial ultrasound facilitated diagnosis of intraventricular hemorrhage. In 1979, loss of cerebral autoregulation in sick newborn infants was demonstrated. In the 1980’s, studies demonstrated the importance of intravascular factors in provoking hemorrhage. In 1983, the association of cerebral blood flow velocity fluctuations and subsequent hemorrhage was demonstrated. In 1994, antenatal steroids use to accelerate lung development was recommended. This was associated with an unanticipated reduction in hemorrhage. In the mid 1990’s early indomethacin administration was associated with a reduction of severe hemorrhage. 相似文献
107.
采用湿法纺丝工艺纺制了聚醚酰亚胺(PEI)-聚苯醚砜(PES)中空纤维H2-N2和He-N2分离共混膜,得到H2和He的渗透通量及选择性为:JH2=360GPU,αH2/N2=162,JHe=181GPU,αHe/N2=76.7;研究了芯液组成及其流量对膜性能的影响。通过扫描电镜,分析了中空纤维膜的结构,讨论了膜制备过程中的相转化原理。 相似文献
108.
109.
采用单导管射频消融法治疗12 例预激综合征( W P W) 。12 例中8 例有反复快速性房颤史,3 例须用同步直流电复律,1 例伴有晕厥。旁路分别为左侧8 条,右后间隔2 条,右后侧及右前间隔各1 条,右侧者有1 例并存1 条左侧隐匿旁路。全部旁路一次消融成功。术中未诱发房颤。随访5 ~17 月未见复发。 相似文献
110.
Neurological prognosis correlated with variations over time in the number of subependymal nodules in tuberous sclerosis 总被引:2,自引:0,他引:2
In tuberous sclerosis (TS), brain CT reveals subependymal nodules, cortical tubers and white matter lesions. This study is a retrospective analysis of the relationship between the variations over time in the number of subependymal nodules and the clinical course in cases of tuberous sclerosis. Twenty-four children with tuberous sclerosis, who attended the National Children's Hospital as outpatients, were followed by means of brain CT examinations for 7 years and 1 month on average. Cranial MRI was also performed in 22 cases. Brain CT disclosed subependymal nodules already in early infancy. In almost all cases, the number of subependymal nodules gradually increased with age, especially around the frontal horn of the lateral ventricle. The increase stopped at around age 10. The cases with five or more subependymal nodules at the initial or subsequent CT examination (17 patients; Group A) exhibited a significantly greater number of cortical tubers than those with less than five (five patients; Group B) and had white matter lesions unlike Group B. In addition, the number of cases with either infantile spasms or mental retardation was significantly higher in Group A than Group B (P<0.005). In conclusion, the number of ventricular subependymal nodules may allow prediction of the severity of the cerebral dysfunction in TS. Our results suggest that its variation may reflect the degree of the embryologic disorder when neuronal cells grow in the early gestational period. 相似文献