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101.
102.
A Marciniak GR Sutherland M Marciniak P Claus B Bijnens M Jahangiri 《European journal of echocardiography》2009,10(1):112-119
Aims: Early left ventricular (LV) dysfunction in asymptomatic patientswith severe aortic regurgitation (AR) may go undetected dueto the lack of a sufficiently sensitive diagnostic tool. Ultrasonicstrain/strain rate (S/SR) imaging should now provide such sensitivityin detecting early dysfunction in regional LV systolic deformation.The aim of this study was to understand and define the changesin LV regional systolic deformation based on S/SR imaging inpatients with asymptomatic or minimally symptomatic AR. Methods and results: Eighty-one individuals were studied: 59 asymptomatic patientswith isolated non-ischaemic AR who were divided into three sub-groupssuch as mild, moderate, and severe AR and 22 age-matched healthysubjects. All patients underwent standard echocardiographicexaminations including a tissue Doppler imaging study. For LVradial deformation, the posterior wall (LVPW) was examined.To assess LV longitudinal deformation, S and SR data were acquiredfrom the LV lateral wall and septum. Radial as well as longitudinalpeak systolic SRs were significantly decreased in patients withboth moderate AR (LVPW, P = 0.0009; septum, P = 0.03; LV lateralwall, P = 0.0009) and severe AR (P < 0.0001) compared withhealthy subjects. Changes in regional LV deformation correlatedinversely both with LV end-diastolic volume and with end-systolicvolume. Conclusions: Strain rate imaging is a sensitive tool in detecting the spectrumof changes in radial and longitudinal deformation in asymptomaticor minimally symptomatic patients with AR. The index where volumewas corrected by deformation should form the basis for predictingsubclinical LV dysfunction in patients with increasing LV dilatation. 相似文献
103.
为探讨预防动脉粥样硬化的药物普罗布考,维生素C和维生素E是否抑制内皮细胞表面粘附分子表达和白细胞一内皮细胞的粘附,以及这种抑制是否通过影响核因子-kB的活性来实现的,在液体流动小室中进行细胞粘附实验。用ELISA方法测定内皮细胞粘附分子E-选择素的表达;用电泳迁移率分析测定内皮细胞核因子-kB的活性,经肿瘤坏死因子α刺激的内皮细胞核因子-B活性增加,粘附分子E-选择素的表达上调(是基础水平的3.5倍),其表面HL60细胞的粘附增加(是基础水平的4-26倍),而抗氧化剂PDTC使所有这些变化都受到抑制。PDTC浓度为18umol/L时对粘附分子E-选择素的表达呈最大半抑制;PDTC浓度为52umol/L时对内皮细胞表面HL60细胞的粘附呈最大半抑制,普罗布考,维生素C和维生素E对肿瘤坏死因子α诱导的粘附分子表达和HL60细胞与内皮细胞的粘附没有作用,对核因子-kB的活性没有影响,临床上常用的这三种抗氧化剂并未影响作为动脉粥样硬化始动机制之一的E-选择素介导的白细胞-内皮细胞粘附水平。 相似文献
104.
Waller EK; Olweus J; Lund-Johansen F; Huang S; Nguyen M; Guo GR; Terstappen L 《Blood》1995,85(9):2422-2435
There is a long-standing controversy as to whether a single bone marrow (BM)-derived cell can differentiate along both hematopoietic and stromal lineages. Both primitive hematopoietic and stromal progenitor cells in human BM express the CD34 antigen but lack expression of other surface markers, such as CD38. In this study we examined the CD34+, CD38- fraction of human fetal BM by multiparameter fluorescence- activated cell sorting (FACS) analysis and single-cell sorting. CD34+, C38- cells could be divided into HLA-DR+ and HLA-DR- fractions. After single-cell sorting, 59% of the HLA-DR+ cells formed hematopoietic colonies. In contrast, the CD34+, CD38-, HLA-DR- cells were much more heterogeneous with respect to their light scatter properties, expression of other hematopoietic markers (CD10, CD36, CD43, CD49b, CD49d, CD49e, CD50, CD62E, CD90w, CD105, and CD106), and growth properties. Single CD34+, CD38-, HLA-DR- cells sorted into individual culture wells formed either hematopoietic or stromal colonies. The presence or absence of CD50 (ICAM-3) expression distinguished hematopoietic from stromal progenitors within the CD34+, CD38-, HLA-DR- population. The CD50+ fraction had light scatter characteristics and growth properties of hematopoietic progenitor cells. In contrast, the CD50- fraction lacked hematopoietic progenitor activity but contained clonogenic stromal progenitors at a mean frequency of 5%. We tested the hypothesis that cultures derived from single cells with the CD34+, CD38- , HLA-DR- phenotype could differentiate along both a hematopoietic and stromal lineage. The cultures contained a variety of mesenchymal cell types and mononuclear cells that had the morphologic appearance of histiocytes. Immunophenotyping of cells from these cultures indicated a stromal rather than a hematopoietic origin. In addition, the growth of the histiocytic cells was independent of the presence or the absence of hematopoietic growth factors. Based on sorting more than 30,000 single cells with the CD34+, CD38-, HLA-DR- phenotype into individual culture wells, and an analysis of 864 stromal cultures initiated by single CD34+ BM cells, this study does not support the hypothesis of a single common progenitor for both hematopoietic and stromal lineages within human fetal BM. 相似文献
105.
Treatment of compulsive behaviour in eating disorders with intermittent ketamine infusions 总被引:2,自引:0,他引:2
Mills IH; Park GR; Manara AR; Merriman RJ 《QJM : monthly journal of the Association of Physicians》1998,91(7):493-503
We have previously shown that eating disorders are a compulsive behaviour
disease, characterized by frequent recall of anorexic thoughts. Evidence
suggests that memory is a neocortical neuronal network, excitation of which
involves the hippocampus, with recall occurring by re-excitement of the
same specific network. Excitement of the hippocampus by glutamate-NMDA
receptors, leading to long-term potentiation (LTP), can be blocked by
ketamine. Continuous block of LTP prevents new memory formation but does
not affect previous memories. Opioid antagonists prevent loss of
consciousness with ketamine but do not prevent the block of LTP. We used
infusions of 20 mg per hour ketamine for 10 h with 20 mg twice daily
nalmefene as opioid antagonist to treat 15 patients with a long history of
eating disorder, all of whom were chronic and resistant to several other
forms of treatment. Nine (responders) showed prolonged remission when
treated with two to nine ketamine infusions at intervals of 5 days to 3
weeks. Clinical response was associated with a significant decrease in
Compulsion score: before ketamine, mean +/- SE was 44.0 +/- 2.5; after
ketamine, 27.0 +/- 3.5 (t test, p = 0.0016). In six patients
(non-responders) the score was: before ketamine, 42.8 +/- 3.7; after
ketamine, 44.8 +/- 3.1. There was no significant response to at least five
ketamine treatments, perhaps because the compulsive drive was
re-established too soon after the infusion, or because the dose of opioid
antagonist, nalmefene, was too low.
相似文献
106.
Bash RO; Crist WM; Shuster JJ; Link MP; Amylon M; Pullen J; Carroll AJ; Buchanan GR; Smith RG; Baer R 《Blood》1993,81(8):2110-2117
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study. 相似文献
107.
Acute cytomegalovirus (CMV) infection is a commonly encountered complication in the post liver transplant setting. We present a case of a 71-year-old male with acute CMV infection, initially presenting with a gastrointestinal bleed due to acute CMV gastritis and later on complicated by acute venous thromboembolism occurring as an unprovoked event in the post liver transplant period. Traditional risk factors for venous thromboembolism have been well described in the medical literature. Sporadic cases of thromboembolism due to CMV infection in the immune compromised patients have been described, especially in the post kidney transplant patients. Liver transplant recipients are equally prone to CMV infection particularly in the first year after successful transplantation. Venous thromboembolism in this special population is particularly challenging due to the fact that these patients may have persistent thrombocytopenia and anticoagulation may be a challenge for the treating physician. Since liver transplantation is severely and universally limited by the availability of donor organs, we feel that this case report will provide valuable knowledge in the day to day management of these patients, whose clinical needs are complex and require a multidisciplinary approach in their care and management. Evidence and pathophysiology linking both the conditions is presented along with a brief discussion on the management, common scenarios encountered and potential impact in this special group of patients. 相似文献
108.
Case report Leptomeningeal involvement in diffuse intrinsic brain stem gliomas is rarely diagnosed clinically and in majority of the instances diagnosed only on postmortem examination. We report two cases of diffuse pontine glioma diagnosed clinicoradiologically and treated with conventional radiotherapy.Observations On follow-up, both patients showed clinical features suggestive of meningeal spread although imaging for pontine tumor showed stable disease. Leptomeningeal disease in the spine was confirmed on imaging and in one case by cerebrospinal fluid examination also. During the follow-up of patients with pontine glioma, the possibility of leptomeningeal involvement must be borne in mind. 相似文献
109.
Bizhan Helli Majid Mohammad Shahi Karim Mowla Mohammad Taha Jalali Hossein Khadem Haghighian 《Phytotherapy research : PTR》2019,33(9):2421-2428
Inflammation is one of the main characteristics of rheumatoid arthritis. Based on the antiinflammatory properties of sesame, this study was conducted to evaluate the sesamin supplement effects on serum levels of some proteolytic enzymes, inflammatory biomarkers, and clinical indices in women with rheumatoid arthritis. In this randomized, triple‐blind, placebo‐controlled clinical trial, 44 patients were randomly divided in intervention and control groups. Patients received 200‐mg/day sesamin supplement or placebo in the intervention and control group for 6 weeks. Serum levels of proteolytic enzymes (hyaluronidase, aggrecanase, and matrix metalloproteinases‐3) and inflammatory biomarkers (hs‐CRP, IL‐1β, IL‐6, TNF‐α, and cyclooxygenase‐2) were measured with enzyme‐linked immunosorbent assay method at the beginning and end of the study. After intervention, serum levels of hyaluronidase and matrix metalloproteinases‐3 decreased significantly in sesamin group. Also, serum levels of hs‐CRP, TNF‐α, and cyclooxygenase‐2 in intervention group were significantly decreased in intervention group compared with placebo group. Sesamin supplementation also caused a significant reduction in the number of tender joints and severity of pain in these patients. According to the results, it seems that the sesamin by reducing inflammatory mediators can relieve clinical symptoms and pathological changes that caused by inflammatory impairment in patients with rheumatoid arthritis. 相似文献
110.
Dayananda S Sharma Rakesh Jalali Chandrashekhar M Tambe Deepak D AnimeshDeshpande 《Radiotherapy and oncology》2004,70(1):49-54
BACKGROUND AND PURPOSE: The aim of this work was to measure the dose to foetus both in vivo and in vitro during three-dimensional conformal radiation therapy (3DCRT) in a pregnant patient with a pituitary adenoma. The study was then extended to assess the components contributing to the foetal dose such as collimator scatter, internal scatter, head leakage, wedge scatter and multileaf collimator (MLC) effect. PATIENTS AND METHODS: A 30-year-old pregnant woman with a non-functioning pituitary macroadenoma was planned for 3DCRT with 6MV X-ray using four equally weighted MLC-shaped non-coplanar wedged portals. In vivo dosimetry was carried out using thermoluminescent (TL) phosphor powder, which was placed at different positions on the patient, corresponding to different locations in the uterus and also at external os. In vitro measurements were also performed on a simulated phantom using the same set-up parameters and beam arrangement to verify the in vivo measured dose. Experiments were carried out to measure the respective contributions of different components towards peripheral dose. RESULTS: In vitro measured dose to foetus was found to be slightly more than that of in vivo measurement with a maximum of 0.044% of the prescribed dose of 45Gy, which corresponded to 0.0199+/-0.0008Gy. Thermoluminescence dosimeter (TLD) kept at the external os of the patient showed a dose of 0.031% of the prescribed dose. Among the various components of the peripheral dose (foetal dose) measured, head leakage was found to be the leading cause contributing 52%, followed by wedge scatter (31%), collimator scatter (14%) and internal scatter (13%). The use of MLC reduced not only the volume of normal brain irradiation as compared to open fields but also the peripheral dose by 10%. CONCLUSION: Radiotherapy of brain tumours during pregnancy poses a unique clinical situation and decisions to deliver radiotherapy should be taken after detailed in vitro and in vivo dosimetric measurements. Our findings suggest that the beam arrangement using 3-4-fields generally used for 3DCRT of brain tumour with MLC for optimal coverage can be employed for pregnant patients even in early trimester. A possible increase in foetal dose from wedges to a large extent can be compensated with the use of MLC. 相似文献