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101.
It is largely unknown why a variety of bacteria present in the oral cavity are capable of establishing themselves in the periodontal pockets of nonimmunocompromised individuals in the presence of competent immune effector cells. In this paper we present evidence for the immunosuppressive role of Fusobacterium nucleatum, a gram-negative oral bacterium which plays an important role in the generation of periodontal disease. Our studies indicate that the immunosuppressive role of F. nucleatum is largely due to the ability of this organism to induce apoptotic cell death in peripheral blood mononuclear cells (PBMCs) and in polymorphonuclear cells (PMNs). F. nucleatum treatment induced apoptosis of PBMCs and PMNs as assessed by an increase in subdiploid DNA content determined by DNA fragmentation and terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end-labeling assays. The ability of F. nucleatum to induce apoptosis was abolished by either heat treatment or proteinase digestion but was retained after formaldehyde treatment, suggesting that a heat-labile surface protein component is responsible for bacterium-mediated cell apoptosis. The data also indicated that F. nucleatum-induced cell apoptosis requires activation of caspases and is protected by NF-kappaB. Possible mechanisms of F. nucleatum's role in the pathogenesis of periodontal disease are discussed. 相似文献
102.
For patients with coronary artery disease and left ventricular dysfunction who undergo revascularization, it is important to estimate the left ventricular ejection fraction (LVEF) improvement after revascularization, as this is a strong indicator of the long-term outcome. Identification of viable segments from echocardiography has been considered a predictive sign of LVEF improvement. However, a quantitative relation between segmental function recovery and global ejection fraction improvement has not been established. There is a clinical need to determine parameters that are predictive to LVEF improvement. A cylindrical left ventricular model is proposed to establish the relation between segmental myocardial function and LVEF based on a 12-segment echocardiograph model. Model results show that LVEF improvement is directly related to the contraction ratio in normal segments and a weighted sum of the number of viable segments that recover to normal or hypokinetic, which is equal to a weighted sum of the change in wall motion scores. This new combined parameter is a better predictor of the amount of LVEF improvement than the total number of viable segments or preoperative ejection fraction. The predictive value of the model was illustrated in a group of four patients with coronary artery disease who underwent revascularization. 相似文献
103.
STUDY OBJECTIVES: Very few studies have evaluated narcolepsy in Asian countries, outside of Japan. Our goal was to study narcolepsy at the genetic, clinical and pathophysiological level in Korea. DESIGN: Prospective study of consecutive patients and age matched controls. Clinical data ascertained from the Stanford Sleep Inventory, Polysomnography and MSLT data, as well as clinical notes. High resolution DRB1 and DQB1 typing in all subjects and studies of CSF hypocretin-1 was also evaluated in a subset of patients. PARTICIPANTS AND SETTING: 20 patients diagnosed at St. Vincent and Korea University Hospitals (Seoul, Korea). 21 Korean control subjects. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: For narcoleptic subjects, mean age was 28.2 years old and 45% were female. Mean BMI was 23.9+/-3.4 kg/m2, a significantly higher value than that expected in an age- and sex-matched sample (p<0.01). All patients had sleepiness and cataplexy while the prevalence of other symptoms ranged from 60-75%. All but 2 subjects were HLA-DR15 (DR2), DQB1*0602 positive (90%). This high DQB1*0602 percentage compared with 24% DQB1*0602 positivity in 21 control Koreans. Protective effects were observed for the DQB1*0601 and DRB1*0406 alleles, Hypocretin (orexin) CSF studies were also performed in 6 cataplectic subjects, all of which had undetectable CSF hypocretin levels. Two of these subjects had started narcolepsy less than 1 year before analysis yet had undetectable hypocretin levels. CONCLUSION: These results illustrate the similarity of narcolepsy-cataplexy in Korea in comparisons with other more studied populations. We also identified a new potential HLA protective subtype, HLA-DRB1*0406. 相似文献
104.
T H Lim J S Lee B I Choi I O Kim C H Suh M C Han C W Kim 《Journal of computer assisted tomography》1987,11(3):474-479
The pattern of renal enhancement and washout of contrast medium was observed on sequential follow-up CT in 12 patients with Korean hemorrhagic fever, in which acute renal failure is one of the most important clinical features. Renal contrast enhancement and contrast medium washout were delayed longer in patients with severe oliguric renal failure. The delayed washout peaked at 4-5 days and did not return to normal until 8-9 days in the patients with severe oliguria; in the patients without severe oliguria the times were 1-2 days and 3-4 days, respectively. A characteristic "cart-wheel" pattern was observed during the washout stage in patients without severe oliguria. This "cart-wheel" pattern of washout is thought to result from relief of vasoconstriction and repair of tubular function. Multifocal "wedge-shaped" nonenhanced areas of the kidney, seen on the 2 week follow-up postcontrast CT, are thought to be ischemic zones due to persistent vasoconstriction. On the 6 week follow-up postcontrast CT in one patient, scarring of the kidney was detected in the same area that did not enhance on the 2 week CT. This scarring is thought to be a result of permanent vasoconstriction. 相似文献
105.
Han Ji-sheng韩济生Department of Physiology Beijing Medical University Beijing 《中华医学杂志(英文版)》1987,100(6):459-464
roiiowing the rapid progress iri molecular bio
logy, we are moving from the period of "one peptide
a year" to a period of "one peptide a day". To
cope with the rapid emergence of novel biologically
active peptides, new techniques are needed to clarify
their physiological functions. Evidence is presented
here to show that antibody microinjection is a rapid
and reliable method to evaluate the functions of
endogenously released peptides. It is especially
useful when no specific receptor antagonist is yet
avaiilable for pharmacological study. 相似文献
106.
Sun Chang-ti孙昌惕 Cao Lu-cheng曹履诚and Han Ke-han韩可汉Institute of Urology Beijing Medical University Beijing 《中华医学杂志(英文版)》1987,100(12):935-939
The formation of calcium oxalate nephrolithiasis
can be estimated by measuring the concentration of
calcium oxalate versus the inhibitory role of crystal
formation in the urine. In recent studies, the
calcium oxalate saturation index and the inhibitory
activity (by modified Sarig's method) of the urine
during fasting and after oral calcium loading in
normal subjects and in patients with calcium nepliro-
lithiasis were determined. It was shown that, in
normal comrols after calcium loading the inhibitory
activity of the urine increased in parallel with the
increase in urinary excretion of calcium oxalate; in
contrast, in patients with kidney stones, it remained
unchanged or fell slightly. This abnormal response
might result in a disturbance of the saturation-inhibi-
tion balance and formation of kidney stone. In
normal individuals, there may be a "protective re-
sponse" to prevent the precipitation of calcium
oxalate when the urrine is oversaturated with calcium
oxalate while a defect of the "protective response"
in patients may be an important factor in calcium
oxalate stone formation. 相似文献
107.
Seventy three patients with disseminated diffuse non-Hodgkin's lymphomas were treated with combinations of cyclophosphamide, vincristine sulfate, prednisone, and doxorubicin with and without 2 weekly doses of oral methotrexate in "intermediate" doses, followed by calcium leucovorin rescue. The addition of methotrexate did not increase the complete remission rate, the remission duration, or the survival (P value = 1.0, 0.74, and 0.78, respectively) in patients who did not have previous chemotherapy treatment. In previously treated patients, the complete remission rate was somewhat higher and the remission duration and survival were longer among those patients treated with the methotrexate containing program; however these differences were not statistically significant (P values = 0.88, 0.81, and 0.46, respectively). There was substantial morbidity and mortality during treatment with both treatment arms, among patients aged more than 60 years. 相似文献
108.
Wong Jasin Ezeife Nnaemezie Kudla Angelika Crown Deborah Trierweiler Robert Capraro Pamela Tomazin Stephanie Su Han Pham Tri Heinemann Allen W. 《Journal of occupational rehabilitation》2022,32(3):464-472
Journal of Occupational Rehabilitation - Purpose The COVID-19 pandemic has disproportionately affected the lives of people with disabilities (PWD). How the pandemic affects the employment of PWD... 相似文献
109.
溃疡性结肠炎(UC)是一种临床常见的消化系统疾病,致病机制尚不明确,病情复杂多变,迁延难愈,治疗周期漫长,且无特效药。目前,UC的治疗多采用皮质类固醇、氨基水杨酸及生物制剂等西医手段,短时间起效快,疗效确切。但随着用药时间的延长,部分患者会出现耐药性和加剧病情发展,导致结肠癌的发生。有研究发现,氧化应激是UC重要的致病因素之一,影响着UC的发生、发展。氧化应激是机体内氧化产物与抗氧化系统不平衡的一种应激状态,丙二醛(MDA)、活性氧(ROS)、一氧化氮(NO)等氧化产物的过表达或者超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽(GSH)抗氧化酶的不足都会导致氧化应激的发生。值得注意的是,中医药作为我国独有的医学特色,运用中医药治疗UC疾病已经取得显著的成效。研究表明,中医药一方面通过抑制代谢产物的堆积,有效抑制UC发生,另一方面,通过提高抗氧化系统,达到拮抗UC发展的治疗效果。因此,以中医药调节氧化平衡状态作为诊疗思路,可能是未来治疗UC疾病的新手段、新方向。基于上述研究,该文总结了氧化应激关键致病蛋白与UC发生、发展的作用机制,归纳了中药有效成分、单味中药、中药复方、针灸调控氧化应激上下游靶点蛋白,减轻肠黏膜病理损害,降低结肠损伤指数,以及丰富肠道菌群,增加结肠长度,改善UC临床症状,以期为扩大中医药治疗UC疾病的应用范围,提供可靠的科学理论依据。 相似文献
110.