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71.
OBJECTIVES: GI blood loss is the most common cause of iron deficiency anemia (IDA) in postmenopausal women and menstrual blood loss in premenopausal women. We aimed to evaluate the diagnostic yield of endoscopy in women with IDA and to define predictive factors of a GI lesion. METHOD: Clinical, biological, endoscopic, and histological data from patients with IDA were systematically collected on a computer. Multivariate analysis (logistic regression) was performed to determine whether these data were associated with a GI lesion. RESULTS: Between January, 1989 and June, 1999, 241 consecutive women had endoscopies for IDA (mean age = 52.3 +/- 21.8 yr). A substantial GI lesion was detected in 119 patients (49.4%). Ten patients (4%) had both upper and lower GI lesions. A source of IDA was revealed by upper endoscopy in 86 cases (35.6%) and by colonoscopy in 33 (13.7%). The most common upper lesions were peptic ulceration (42/241 [17.4%]), esophagitis (15/241 [6.2%]), and cancer (9/241 [3.7%]). Colonic cancer (15/241 [6.2%]) and polyps (10/241 [4.1%]) were the most frequent lesions detected by colonoscopy. Predictive factors (odds ratio, 95% CI) of GI lesions diagnosed by endoscopy were abdominal symptoms (8.3, 3.9-17.2), age > 50 yr (4.4, 2.1-9.2), and Hb < 9 g/dl (3, 1.5-6.1). Thirty-one women (13%) had none of these predictive factors; in this group only two lesions were identified (one esophagitis and one duodenal ulcer). The positive predictive value of these three independent predictors was 87%, and the negative predictive value was 93.5%. CONCLUSION: Endoscopy revealed a source of IDA in 49.4% of cases. Three predictive factors of GI lesion were identified. Endoscopic investigation should be avoided in women without these three predictive factors. Conversely, these factors are strongly associated with a GI lesion.  相似文献   
72.
The goal of the study was to examine the effect of different types of eye movements on postural stability. Ten healthy young adults (25 ± 3 years) participated in the study. Postural control was measured by the TechnoConcept© platform and recorded in Standard Romberg and Tandem Romberg conditions while participants performed five oculomotor tasks: two fixation tasks (central fixation cross, without and with distractors), two prosaccade tasks toward peripheral targets displayed 4° to the left or to the right of the fixation cross (reactive saccades induced by a gap 0 ms paradigm and voluntary saccades induced by an overlap 600 ms paradigm) and one antisaccade task (voluntary saccade made in the opposite direction of the visual target). The surface, the length, and the mean speed of the center of pressure were analyzed. We found that saccadic eye movements improved postural stability with respect to the fixation tasks. Furthermore, antisaccades were found to decrease postural stability compared to prosaccades (reactive as well as voluntary saccades). This result is in line with the U-shaped nonlinear model described by Lacour et al. (Neurophysiol Clin 38:411–421, 2008), showing that a secondary task performed during a postural task could increase (prosaccade task) or decrease (antisacade task) postural stability depending on its complexity. We suggest that the different degree of attentional resources needed for performing prosaccade or antisaccade tasks are, most likely, responsible for the different effect on postural control.  相似文献   
73.

Background

Despite the use of combined antiretroviral therapy, HIV-infected individuals have a higher risk of developing B-cell lymphoma compared to the general population. We aim to explore whether lymphocyte activation, increase in Th1 response as well as markers of EBV reactivation, may precede lymphoma diagnosis.

Methods

Thirteen cases and 26 controls matched on CD4+ T-cell count and HIV plasma viral load were identified. Samples were collected 0 to 5 years prior to B-cell lymphoma diagnosis. Seven out of 13 (54 %) and 16/26 (61.5 %) of cases and controls were receiving antiretroviral therapy at the time of sampling, respectively. CD8+ T-cell activation and Th1 cytokine concentrations were measured before lymphoma onset, together with IgG antibodies directed against viral capsid antigen (VCA) and serum levels of EBV DNA.

Results

A higher level of CD8+ T-cell activation was observed in patients developing lymphoma. Four out of seven Th1 cytokine serum concentrations were significantly higher in patients with lymphoma than in the control group: IL-2R, IL-12p40/70, IFN-γ-inducible protein 10 (IP-10) and monokine induced by IFN-γ (MIG). Anti-VCA IgG level were significantly higher in cases than in controls. Four cases (30 %) but no controls had detectable EBV DNA in serum.

Conclusion

A higher level of T-cell activation, Th1 cytokine serum concentration and markers of EBV replication, preceded B-cell lymphoma diagnosis. This may suggest that viral antigen stimulation is associated with the genesis of lymphoma in HIV-infected patients.  相似文献   
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76.

INTRODUCTION

The elderly population is growing rapidly. Political and socio-economic changes led to the demographic transition in this population with the highest number of surgeries and as well as many comorbidities.

OBJECTIVE

To evaluate the impact of cardiovascular intervention on quality of life of elderly patients after three and six months.

METHODS

Analytical prospective cohort study with elderly between 60 and 80 years of age, of both sexes, with a diagnosis of coronary artery disease and underwent cardiovascular intervention during the period June 2010 to June 2011. Data were collected by individual interviews in the pre and postoperative periods (after three and six months) by telephone. We used the SF-36 to analyse quality of life in order to assess the physical and mental health of the study population.

RESULTS

Of the 44 individuals evaluated, 59.1% were men, 75% in the range of 65 to 74 years, 38.6% were white and 38.6% were black, 31.8% were uneducated, 43.2% were married and 68.2% had less than a minimum wage. Prevailed patients: non-diabetics (68.2%), non-obese (81.8%), hypertensive (84.1%), non-alcoholic and non-smokers (68.2% and 61.4%, respectively). A significant increase in the average of the SF-36 scores between pre and post-surgical periods (three and six months) for the domains: functional capacity, pain, general health, vitality and emotional aspect.

CONCLUSION

The elderly population undergoing intervention may have cardiovascular benefits and improvements of quality of life. Physical fitness improvement measures can be taken to resume that capability.  相似文献   
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Rezaie  AR; Esmon  CT 《Blood》1994,83(9):2526-2531
Protein C is a vitamin K-dependent plasma serine protease zymogen, which upon activation, functions as an anticoagulant. Protein C activation is catalyzed by a complex of thrombin (T) with thrombomodulin (TM). This activation is Ca(2+)-dependent, but Ca2+ inhibits protein C activation by thrombin alone. In most proteases, specificity is determined primarily by the residues that lie near the scissile bond. In protein C, the P2 position is Pro, whereas in the fibrinogen A chain, P2 is Val. We have expressed a Pro-->Val mutant of protein C (P168V) in mammalian cells. At saturating Ca2+, the P168V and wild-type proteins were activated by the T-TM complex equivalently, but half maximal rates of activation were obtained at 50 mumol/L Ca2+ for wild type and approximately 5 mmol/L Ca2+ for the P168V mutant. In the absence of TM, Ca2+ no longer inhibited the activation of the P168V mutant. These results indicate that Pro168 influences the Ca(2+)- dependent conformational changes in protein C that control activation. Recently, a patient with thrombotic complications has been identified with a Pro168-->Leu substitution. Both the P168V and the P168L mutation lead to impaired secretion caused by retention within the cell.  相似文献   
80.
Ball  ED; Mills  LE; Coughlin  CT; Beck  JR; Cornwell  GG d 《Blood》1986,68(6):1311-1315
Second or third chemotherapy-induced remissions in acute myelogenous leukemia (AML) are limited by early relapse of the leukemia. We developed monoclonal antibodies (MoAbs) that are cytotoxic to myeloid leukemia cells to treat bone marrow from these patients ex vivo for autologous transplantation. In this pilot study, bone marrow was harvested from ten patients with AML in remission, treated with one or two complement-fixing MoAbs, PM-81 and AML-2-23, which react with myeloid differentiation antigens, incubated with rabbit complement, and cryopreserved. These MoAbs were chosen because they have broad reactivity with AML cells but not with pluripotent progenitor cells. At the time of transplant, 6 patients were in second complete remission, 1 each was in third complete or partial remission, and 2 were in early first relapse. The patients were treated with cyclophosphamide (60 mg/kg a day for 2 days) and total body irradiation (200 cGy twice a day for 3 days) and given infusions of MoAb-treated bone marrow. Full bone marrow reconstitution was observed in eight patients; two patients did not recover platelets. Seven of the ten patients are surviving and disease-free at 21.0, 15.0, 13.0, 10.0, 6.0, 3.0, and 2.0 months posttransplant. Treating bone marrow with MoAbs to myeloid differentiation antigens does not interfere with pluripotential stem cell engraftment. Longer follow-up and a controlled study are necessary to prove that the apparent efficacy of this therapeutic approach in some patients is attributable to MoAb-mediated killing of leukemia cells.  相似文献   
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