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排序方式: 共有2583条查询结果,搜索用时 15 毫秒
91.
Juliano L. Fernandes Matheus A. Silveira Kleber Fertrin Samira Lauar Andre Fattori Otavio Coelho Flavia Pegado Junqueira Guilherme Moura da Cunha Antonio Carlos Coutinho Jr. Fabricio B. Pereira Monica Verissimo Sara T. Saad 《Annals of hematology》2012,91(12):1839-1844
Thalassemia major (TM) patients have altered ventricular volumes and ejection fraction compared to normals, although evidence for these findings stem from restricted patient groups and has never been reproduced. We sought to evaluate cardiac parameters by cardiovascular magnetic resonance (CMR) in a group of young TM patients not covered by previous studies that are more representative of the TM population in many countries. Seventy patients including 40 TM with normal myocardial iron concentrations, and 30 age- and gender-matched normal (NL) volunteers underwent a CMR study for assessment of left and right ventricle volumes and function using a 1.5-T scanner. Left and right ventricle ejection fraction, indexed systolic and diastolic volumes, and indexed mass were compared between the two groups. Mean age of TM patients was 18.2?±?7.1 versus 17.5?±?8.5?years in NL with no significant differences (P?=?0.73). There was no difference in left ventricular (LV) ejection fraction between the groups (TM 64.9?±?5.7?%, NL 64.9?±?5.2?%; P?=?0.97). LV normalized end-diastolic and end-systolic volumes were significantly higher in patients with TM compared to NL volunteers (76.8?±?19.4 versus 66.6?±?11.7?mL/m2, P?=?0.008, and 27.0?±?8.8 versus 23.6?±?5.0?mL/m2, P?=?0.045). LV indexed mass was also higher in TM patients compared to NL (51.2?±?11.9 versus 42.0?±?8.5?g/m2, P?<?0.001). No significant differences were observed in right ventricular parameters. In conclusion, younger patients with TM do not present different left or right ventricular function values compared to normal controls despite having increased left ventricular volumes and mass. 相似文献
92.
MD Bastos S Santos A Souza B Finkmoore O Bispo T Barreto I Cardoso I Bispo F Bastos D Pereira L Riley E Carvalho 《BMC infectious diseases》2012,12(1):199
ABSTRACT: BACKGROUND: HTLV-1 is associated with increased susceptibility to Mycobacterium tuberculosis infection and severity of tuberculosis. Although previous studies have shown that HTLV-1 infected individuals have a low frequency of positive tuberculin skin test (TST) and decreasing in lymphoproliferative responses compared to HTLV-1 uninfected persons, these studies were not performed in individuals with history of tuberculosis or evidence of M. tuberculosis infection. Therefore the reasons why HTLV-1 infection increases susceptibility to infection and severity of tuberculosis are not understood.The aim of this study was to evaluate how HTLV-1 may influence the clinical, bacteriologic and immunologic presentation of tuberculosis. METHODS: The study prospectively enrolled and followed 13 new cases of tuberculosis associated with HTLV-1 (cases) and 25 patients with tuberculosis without HTLV-1 infection (controls). Clinical findings, bacterial load in the sputum, x-rays, immunological response and death were compared in the two groups. RESULTS: There were no differences in the demographic, clinical and TST response between the two study groups. IFN-gamma and TNF-alpha production was higher in unstimulated cultures of mononuclear cells of case than in control patients (p < 0.01). While there was no difference in IFN-gamma production in PPD stimulated cultures, TNF-alpha levels were lower in cases than in controls (p = 0.01). There was no difference in the bacterial load among the groups but sputum smear microscopy results became negative faster in cases than in controls. Death only occurred in two co-infected patients. CONCLUSION: While the increased susceptibility for tuberculosis infection in HTLV-1 infected subjects may be related to impairment in TNF-alpha production, the severity of tuberculosis in co-infected patients may be due to the enhancement of the Th1 inflammatory response, rather than in their decreased ability to control bacterial growth. 相似文献
93.
Flavia R. Toledo Aline A. Antunes Francieli C. D. Vannini Liciana V. A. Silveira Luis C. Martin Pasqual Barretti Jacqueline C. T. Caramori 《International urology and nephrology》2013,45(6):1747-1752
Purpose
Malnutrition is a strong predictor of mortality in hemodialysis patients. Several scoring systems for evaluating nutritional status have been proposed. However, they rely on different sets of anthropometric and laboratory markers to make a diagnosis of malnutrition and assess its impact on prognosis. To validate them, nutritional scores should be compared with clinical outcomes. Thus, the purpose of this study was to assess malnutrition by three different nutrition scoring systems and determine which best predicts mortality in hemodialysis patients.Methods
This prospective study included 106 adult chronic hemodialysis patients. Their mean age was 56.3 ± 14.9 years and mean body mass index 24.8 (21.8–28.9); 52 % were men and they had been on dialysis for 24 (5–55) months. Nutritional status was classified according to the diagnostic systems proposed by Wolfson et al. (Am J Clin Nutr 39(4):547–555, 1984), International Society of Renal Nutrition and Metabolism (ISRNM) (Fouque et al. in Kidney Int 73(4):391–398, 2008), and Beberashvili et al. (Nephrol Dial Transplant 25(8):2662–2671, 2010). During about 2 years of follow-up, mortality was assessed by Kaplan–Meier curves, log-rank, and Cox’s models adjusted for diabetes, sex, C-reactive protein, time on dialysis, age, and fractional urea clearance.Results
Twenty-three deaths (21.5 %) occurred during the study period. According to the systems of Wolfson, Beberashvili, and the ISRNM, 54, 32, and 20 % of patients, respectively, had malnutrition. Both univariate and multivariate analyses showed that the ISRNM system was the only one that predicted poorer survival (fourfold higher death risk) in malnourished patients.Conclusions
The scoring system proposed by the ISRNM most accurately identifies patients at higher risk of death. 相似文献94.
Olfactory identification ability implicates the integrity of the orbitofrontal cortex (OFC). The fronto–striatal circuits including the OFC have been involved in the neuropathology of Obsessive Compulsive Disorder (OCD). However, only a few studies have examined olfactory function in patients with OCD. The Brief Smell Identification Test (B-SIT) and tests from the Cambridge Neuropsychological Automated Battery (CANTAB) were administered to 25 patients with OCD and to 21 healthy matched controls. OCD patients showed a significant impairment in olfactory identification ability as well as widely distributed cognitive deficits in visual memory, executive functions, attention, and response inhibition. The degree of behavioural impairment on motor impulsivity (prolonged response inhibition Stop-Signal Reaction Time) strongly correlated with the B-SIT score. Our study is the first to indicate a shared OFC pathological neural substrate underlying olfactory identification impairment, impulsivity, and OCD. Deficits in visual memory, executive functions and attention further indicate that regions outside of the orbitofronto–striatal loop may be involved in this disorder. Such results may help delineate the clinical complexity of OCD and support more targeted investigations and interventions. In this regard, research on the potential diagnostic utility of olfactory identification deficits in the assessment of OCD would certainly be useful. 相似文献
95.
96.
97.
Flavia Mancini Matthew R. Longo Elisa Canzoneri Giuseppe Vallar Patrick Haggard 《The European journal of neuroscience》2013,37(5):768-776
Pain can be modulated by several contextual factors. For example, simply viewing one's own body can reduce pain, suggesting that the visual context may influence the processing of nociceptive stimuli. We studied changes in electroencephalographic (EEG) oscillatory activity related to visual modulation of nociception, comparing cortical oscillations during innocuous or noxious contact heat, while participants viewed either their own hand or a neutral object at the same location. Viewing the body compared with viewing the object reduced the intensity ratings of noxious stimuli, but not of innocuous heat. Time–frequency analysis of EEG data revealed that noxious, as opposed to warm, stimulation was associated with reduced beta (15–25 Hz) power. Classically, such decreases in oscillatory power indicate increases in sensory cortical activation. These event‐related oscillatory changes were moreover modulated by the visual context; viewing one's own body increased noxious stimulation‐induced beta oscillatory activity bilaterally, relative to viewing a neutral object, possibly indicating inhibition of cortical nociceptive processing. These results demonstrate that visual–nociceptive interactions involve changes in sensorimotor EEG rhythms. 相似文献
98.
F Baratto-Filho DP Leonardi BM Crozeta SP Baratto EA Campos FS Tomazinho TM Deliberador 《Brazilian dental journal》2012,23(3):256-262
This paper describes and discusses the multidisciplinary treatment involving a permanent maxillary lateral incisor fused to a supernumerary tooth, both presenting pulp necrosis and periapical lesion. A 15-year-old male patient sought treatment complaining of pain, swelling and mobility on the maxillary right lateral incisor. After clinical and radiographic examination, root canal preparation was performed according to the crown-down technique and a calcium hydroxide dressing was placed for 15 days. The patient returned and the definitive endodontic filling was done with thermomechanical compaction of gutta-percha and sealer. After 18 months, clinical and radiographic examinations were carried out and no pain or swelling was reported. Two years after endodontic treatment, the patient returned for periodontal and cosmetic treatments. Nine months later, a cone-beam computed tomography (CBCT) revealed that the previously detected periodontal defect and periapical lesion were persistent. Apical endodontic surgery was indicated. The supernumerary tooth was removed, the communicating distal surface was filled and the surgical site received bioactive glass and demineralized bovine organic bone. The pathological tissue was submitted to histopathological examination and the diagnosis was periapical cyst. One year after the apical endodontic surgery, CBCT showed bone formation at maxillary lateral incisor apical area. Two years after the surgery, the restoration was replaced due to aesthetic reasons and periapical radiograph showed success after 5 years of treatment. A correct diagnosis and establishment of an adequate treatment plan resulted in a successful management of the case. 相似文献
99.
Foderaro Giuseppe Isella Valeria Mazzone Andrea Biglia Elena Di Gangi Marco Pasotti Fabrizio Sansotera Flavia Grobberio Monica Raimondi Vanessa Mapelli Cristina Ferri Francesca Impagnatiello Valentina Ferrarese Carlo Appollonio Ildebrando Marco 《Neurological sciences》2022,43(5):3053-3063
Neurological Sciences - Mini-Mental State Examination (MMSE) is one of the most used tests for the screening of global cognition in patients with neurological and medical disorders. Norms for the... 相似文献
100.
Joao Seda Neto Eduardo A. Fonseca Helry L. Cândido Renata Pugliese Flavia H. Feier Mario Kondo Rodrigo L. Azambuja Paulo Chapchap 《Pediatric transplantation》2016,20(5):717-722
Many publications discuss the various strategies for vascular reconstruction (VR) in pediatric LDLT. Having knowledge of alternative techniques is helpful in planning transplants. This article presents three case reports that illustrate some of the alternative techniques for HV, PV, and HA reconstruction in pediatric LDLT. It also reviews the available alternative strategies reported for VR in pediatric LDLT. In the first case, a 13‐month‐old girl presented a PRETEXT III HB with invasion of the retrohepatic vena cava. An LLS graft HV was anastomosed to a DD iliac vein graft and subsequently implanted in a “standard” fashion in the recipient. In the second case, a 44‐month‐old boy presented with multifocal HB and portomesenteric thrombosis and the portal inflow was done through a renoportal anastomosis. In the third case, a 22‐month‐old child with a failed Kasai procedure had extensive HA thrombosis. The HA reconstruction was performed with an interposition of the recipient's IMV graft. The use of alternative techniques for VR in pediatric LDLT is paramount to the success of such a complex procedure. Imaging studies can help transplant surgeons outline surgical strategies and define the best technique to be used in each case. 相似文献