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61.
62.
Akwa Y Allain H Bentue-Ferrer D Berr C Bordet R Geerts H Nieoullon A Onteniente B Vercelletto M 《Alzheimer disease and associated disorders》2005,19(4):226-239
Neurodegenerative diseases and, in particular, Alzheimer disease, are characterized by progressive neuronal loss correlated in time with the symptoms of the disease considered. Whereas the symptoms of those incapacitating diseases are beginning to be managed with a relative efficacy, the ultimate objective of therapy nonetheless remains preventing cell (neuronal and/or astrocytic) death in a neurocytoprotective approach. In biologic terms, in the light of progress at basic research level, three strategies may be envisaged: (1) antagonizing the cytotoxic causal events (excess intracellular calcium, accumulation of abnormal proteins, excitotoxic effects of amino acids, oxidative stress, processes related to inflammation, etc.); (2) stimulating the endogenous protective processes (anti-free radical or DNA repair systems, production of neurotrophic factors, potential cytoprotective action of steroids, etc.); (3) promoting damaged structure repair strategies (grafts) or deep brain or cortical neurostimulation with a view to triggering (beyond the symptomatic actions) potential 'protective' cell mechanisms. The clinical transition of the various strategies whose efficacy is being tested in animal and/or cell models, experimental analogs of the diseases, and thus the objective demonstration in humans of pharmacological and/or surgical neurocytoprotection, is currently the subject of considerable methodological debate (What are the right psychometric assessment criteria? What are the most pertinent laboratory or neuroradiological markers, etc.?). A number of clinical trials have been completed or are ongoing with drugs that are reputed to be neuroprotective. Thus, elements of the response are beginning to be generated with a view to determining whether it will soon be possible to effectively slow or even stop the neurodegenerative process whose etiology, in most cases, remains obscure. 相似文献
63.
O'Brien MF Connolly SS Kelly DG O'Brien A Quinlan DM Mulvin DW 《Irish journal of medical science》2004,173(1):23-26
Background Patients with prostate cancer with a pre-operative prostate-specific antigen (PSA) τ;15ng/ml who undergo radical retropubic
prostatectomy (RRP) generally do not have a good outcome, yet may have organ-confined cancer and should be offered the option
of surgery.
Aim To assess the outcome of patients who underwent RRP with a pre-operative PSA ≥ 15ng/ml.
Methods Thirty-four patients, mean pre-operative PSA: 25.46ng/ml (15.03–76.6) and mean Gleason score: 6.4 (5–9) were assessed.
Results Two groups were identified. Group I: 41% (14/34) have no biochemical recurrence to mean follow up of 58 months (30–106).
Mean PSA: 18.8ng/ml (15.03–25.84). Mean Gleason score: 6.1 (5–7). Clinical stage: T1c in 80%. No patient had seminal vesicle
or lymph node involvement. Group II: 59% (20/34) have biochemical recurrence or died (3) from their disease to mean follow
up of 66 months (36–98). Mean PSA: 28.9ng/ml (15.28–76.6). Mean Gleason score: 6.7 (5–9). Clinical stage: T1c in 25%. Eleven
patients had seminal vesicle (8) involvement or positive lymph nodes (3) or both (2).
Conclusion RRP seems feasible in patients whose pre-operative PSA is between 15 and 25ng/ml with stage T1c, Gleason score ≤ 7 and negative
lymph node frozen section. 相似文献
64.
BACKGROUND: The objectives of this study were to describe the use of benzodiazepines in the elderly and to identify socio-demographic and medical factors associated with this use. METHODS: Data on the use of sedative and sleeping drugs were collected from a self-reported questionnaire, in a sample of 1265 elderly subjects (aged 60 to 70 years) interviewed at the first follow-up examination of the EVA Study (Epidemiology of Vascular Aging Study). RESULTS: Use of sedative or sleeping drugs was reported by 28.7% of the participants and use of benzodiazepines by 23%. Most of the benzodiazepines used (71%) had anxiolytic indications, 48% were long-acting compounds (elimination half-life>=20 h.). Among benzodiazepine users, 71% reported using benzodiazepines daily and 77% reported they had been taking benzodiazepines for at least 2 years. Nearly two third of the benzodiazepine users reported taking their medications as prescribed. When they were not compliant, they took benzodiazepines less often and/or at slighter doses than prescribed. Use of benzodiazepines was associated with symptoms of depression or anxiety (women: odds-ratio=2.6 [1.7-4.1]; men: odds-ratio=4.4 [2.4-7.8]) and with regular use of at least three non-psychotropic drugs (women: odds-ratio=2.0 [1.4-2.9]; men: odds-ratio=1.8 [1.1-3.1]). Women with a high educational level or with moderate alcohol consumption were less likely to take benzodiazepines; these associations were not found in men. CONCLUSIONS: The present study shows that benzodiazepines are the sedative and sleeping drugs most widely used by the elderly. Nearly three quarters of benzodiazepine users were chronic users. 相似文献
65.
Acute appendicitis is the most common extra-uterine surgical emergency requiring immediate surgical intervention during pregnancy [1]. Six young female patients presented with appendicitis during May 1996 to May 2001 in different service hospitals. Five patients underwent emergency appendectomy successfully. Gestational age at presentation included first trimester in 4 patients, second trimester in 2 patients and none in third trimester. 84% had pathologically proven acute appendicitis. One patient presented with appendicular lump in first trimester, proved on ultra sonography examination, which was treated by Oshner Sherren regime and subsequently interval appendectomy was done in second trimester. No long term adverse maternal morbidity or mortality was reported. One patient had premature onset of labour and delivered. Natural history of acute appendicitis is not changed during pregnancy while gestational physiological changes obscure the accurate diagnosis of acute appendicitis.Key Words: Acute appendicitis, Appendectomy, Pregnancy 相似文献
66.
67.
Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
68.
Obstetric and nonmalignant gynecologic bleeding: treatment with angiographic embolization 总被引:4,自引:0,他引:4
Eight patients (seven post partum, one post abortion) with massive pelvic hemorrhage related to pregnancy and one patient with uncontrollable bleeding following a cervical biopsy underwent angiography to facilitate the identification and treatment of bleeding sites. In all nine patients pelvic hemorrhage was successfully controlled with embolization under angiographic guidance. Angiographic embolization allowed preservation of the uterus in six patients referred prior to hysterectomy, and one patient subsequently became pregnant. When conservative measures and minor surgical repairs have failed, embolization should be the next step in the treatment of postpartum hemorrhage to avoid major surgery in an unstable patient and to maintain reproductive function. 相似文献
69.
Liu SC; Palek J; Yi SJ; Nichols PE; Derick LH; Chiou SS; Amato D; Corbett JD; Cho MR; Golan DE 《Blood》1995,86(1):349-358
Southeast Asian ovalocytosis (SAO) is an asymptomatic trait characterized by rigid, poorly deformable red cells that resist invasion by several strains of malaria parasites. The underlying molecular genetic defect involves simple heterozygous state for a mutant band 3 protein, which contains a deletion of amino acids 400 through 408, linked with a Lys 56-to-Glu substitution (band 3-Memphis polymorphism). To elucidate the contribution of the mutant SAO band 3 protein to increased SAO red blood cell (RBC) rigidity, we examined the participation of the mutant SAO band 3 protein in increased band 3 attachment to the skeleton and band 3 oligomerization. We found first that SAO RBC skeletons retained more band 3 than normal cells and that this increased retention preferentially involved the mutant SAO band 3 protein. Second, SAO RBCs contained a higher percentage of band 3 oligomer-ankyrin complexes than normal cells, and these oligomers were preferentially enriched by the mutant SAO protein. At the ultrastructural level, the increased oligomer formation of SAO RBCs was reflected by stacking of band 3-containing intramembrane particles (IMP) into longitudinal strands. The IMP stacking was not reversed by treating SAO RBCs in alkaline pH (pH 11), which is known to weaken ankyrin-band 3 interactions, or by removing the cytoplasmic domain of band 3 from SAO membranes with trypsin. Finally, we found that band 3 protein in intact SAO RBCs exhibited a markedly decreased rotational mobility, presumably reflecting the increased oligomerization and the membrane skeletal association of the SAO band 3 protein. We propose that the mutant SAO band 3 has an increased propensity to form oligomers, which appear as longitudinal strands of IMP and exhibit increased association with membrane skeleton. This band 3 oligomerization underlies the increase in membrane rigidity by precluding membrane skeletal extension, which is necessary for membrane deformation. 相似文献
70.
0 引言 人类免疫缺陷病毒 (human immunodeficiencyvirus,HIV) - 1编码的反式激活蛋白 TAT具有独特的跨膜运转方式 ,而且有转导速度快 ,效率高的特点 ,被称为蛋白转导结构域 (protein transduction domain,PTD) [1 ,2 ] .本研究用PCR扩增了慢性粒细胞白血病慢粒 bcr/ abl融合蛋白的基因片段 ,在其 5′端融合 PTD结构域的编码区后在大肠杆菌中进行了表达 .表达产物经纯化后 ,加入培养的 HL 6 0细胞 ,表达的蛋白可直接进入细胞内 .这一结果为用外源蛋白负载(L oading)免疫细胞提供了新的途径 .1 材料和方法1.1 DNA重组 人工合… 相似文献