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81.
82.
Abnormalities of the executive control network in multiple sclerosis phenotypes: An fMRI effective connectivity study 下载免费PDF全文
Ekaterina Dobryakova Maria Assunta Rocca Paola Valsasina Angelo Ghezzi Bruno Colombo Vittorio Martinelli Giancarlo Comi John DeLuca Massimo Filippi 《Human brain mapping》2016,37(6):2293-2304
The Stroop interference task is a cognitively demanding task of executive control, a cognitive ability that is often impaired in patients with multiple sclerosis (MS). The aim of this study was to compare effective connectivity patterns within a network of brain regions involved in the Stroop task performance between MS patients with three disease clinical phenotypes [relapsing‐remitting (RRMS), benign (BMS), and secondary progressive (SPMS)] and healthy subjects. Effective connectivity analysis was performed on Stroop task data using a novel method based on causal Bayes networks. Compared with controls, MS phenotypes were slower at performing the task and had reduced performance accuracy during incongruent trials that required increased cognitive control. MS phenotypes also exhibited connectivity abnormalities reflected as weaker shared connections, presence of extra connections (i.e., connections absent in the HC connectivity pattern), connection reversal, and loss. In SPMS and the BMS groups but not in the RRMS group, extra connections were associated with deficits in the Stroop task performance. In the BMS group, the response time associated with correct responses during the congruent condition showed a positive correlation with the left posterior parietal → dorsal anterior cingulate connection. In the SPMS group, performance accuracy during the congruent condition showed a negative correlation with the right insula → left insula connection. No associations between extra connections and behavioral performance measures were observed in the RRMS group. These results suggest that, depending on the phenotype, patients with MS use different strategies when cognitive control demands are high and rely on different network connections. Hum Brain Mapp, 37:2293–2304, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
83.
84.
Porru D Leva F Parmigiani A Barletta D Choussos D Gardella B Daccò MD Nappi RE Allegri M Tinelli C Bianchi CM Spinillo A Rovereto B 《International urogynecology journal》2012,23(9):1193-1199
Introduction and hypothesis
Intravesical instillations of hyaluronic acid (HA) and chondroitin sulfate (CS) may lead to regeneration of the damaged glycosaminoglycan layer in interstitial cystitis/bladder pain syndrome (IC/BPS).Methods
Twenty-two patients with IC/BPS received intravesical instillations (40?ml) of sodium HA 1.6% and CS 2.0% in 0.9% saline solution (IALURIL?, IBSA) once weekly for 8?weeks, then once every 2?weeks for the next 6?months.Results
The score for urgency was reduced from 6.5 to 3.6 (p?=?0.0001), with a reduction in pain scores from an average of 5.6 to 3.2 (p?=?0.0001). The average urine volume increased from 129.7 to 162?ml (p?0.0001), with a reduction in the number of voids in 24?h, from 14 to 11.6 (p?0.0001). The IC Symptom and Problem Index decreased from 25.7 to 20.3 (p?0.0001), and the Pain Urgency Frequency score, from 18.7 to 12.8 (p?0.0001).Conclusion
The treatment appeared to be effective and well tolerated in IC/BPS in this initial experience. 相似文献85.
Eller-Vainicher C Morelli V Ulivieri FM Palmieri S Zhukouskaya VV Cairoli E Pino R Naccarato A Scillitani A Beck-Peccoz P Chiodini I 《Journal of bone and mineral research》2012,27(10):2223-2230
Patients with adrenal incidentalomas (AIs) and subclinical hypercortisolism (SH) have increased risk of fracture independent of bone mineral density (BMD) and possibly due to reduced bone quality. The trabecular bone score (TBS) has been proposed as a index of bone microarchitecture. The aim of the study was to investigate TBS in AI. In 102 AI patients, SH was diagnosed in the presence of at least two of the following: (1) urinary free cortisol >70 µg/24 h (193.1 nmol/L); (2) cortisol after 1‐mg dexamethasone suppression test (1‐mg DST) >3.0 µg/dL (82.8 nmol/L); or (3) adrenocorticotropic hormone (ACTH) <10 pg/mL (<2.2 pmol/L). In patients and in 70 matched controls, BMD was measured at lumbar spine (LS) and femur (neck [FN] and total [FT]) by dual X‐ray absorptiometry and TBS was assessed in the region of LS‐BMD; BMD and TBS data were reported as Z‐scores. In patients, vertebral deformities were assessed by radiograph. Patients with SH (n = 34) had lower LS‐BMD (?0.31 ± 1.17), FT‐BMD (?0.29 ± 0.91), and TBS (?3.18 ± 1.21) than patients without SH (n = 68, 0.31 ± 1.42, p = 0.03; 0.19 ± 0.97, p = 0.01; ?1.70 ± 1.54, p < 0.0001, respectively) and controls (0.42 ± 1.52, p = 0.02; 0.14 ± 0.76, p = 0.02; ?1.19 ± 0.99, p < 0.0001, respectively). TBS was inversely correlated with 1‐mg DST (β = ?0.26, t = ?2.79, p = 0.006) regardless of age, LS‐BMD, body mass index (BMI), and gender. The presence of fracture was associated with low TBS alone (odds ratio [OR], 4.8; 95% confidence interval [CI], 1.85–12.42, p = 0.001) and with the cluster low TBS plus low LS‐BMD (OR, 4.37; 95% CI, 1.71–11.4, p = 0.002), after adjustment for age, BMI, and gender. Low TBS plus low LS‐BMD showed a good specificity (79%) for predicting fractures, whereas normal TBS (ie, > ?1.5) plus normal LS‐BMD high specificity (88.1%) for excluding fractures. Finally, TBS predicted the occurrence of a new fracture in 40 patients followed for 24 months (OR, 11.2; 95%CI, 1.71–71.41, p = 0.012) regardless of LS‐BMD, BMI, and age. In SH, bone quality, as measured by TBS, is altered. TBS is useful in detecting AI patients at risk of fractures. © 2012 American Society for Bone and Mineral Research. 相似文献
86.
Vacante Marco DAgata Velia Motta Massimo Malaguarnera Giulia Biondi Antonio Basile Francesco Malaguarnera Michele Gagliano Caterina Drago Filippo Salamone Salvatore 《BMC surgery》2012,12(1):1-8
Background
Five percent of all patients with breast cancer have distant metastatic disease at initial presentation. Because metastatic breast cancer is considered to be an incurable disease, it is generally treated with a palliative intent. Recent non-randomized studies have demonstrated that (complete) resection of the primary tumor is associated with a significant improvement of the survival of patients with primary metastatic breast cancer. However, other studies have suggested that the claimed survival benefit by surgery may be caused by selection bias. Therefore, a randomized controlled trial will be performed to assess whether breast surgery in patients with primary distant metastatic breast cancer will improve the prognosis.Design
Randomization will take place after the diagnosis of primary distant metastatic breast cancer. Patients will either be randomized to up front surgery of the breast tumor followed by systemic therapy or to systemic therapy, followed by delayed local treatment of the breast tumor if clinically indicated. Patients with primary distant metastatic breast cancer, with no prior treatment of the breast cancer, who are 18 years or older and fit enough to undergo surgery and systemic therapy are eligible. Important exclusion criteria are: prior invasive breast cancer, surgical treatment or radiotherapy of this breast tumor before randomization, irresectable T4 tumor and synchronous bilateral breast cancer. The primary endpoint is 2-year survival. Quality of life and local tumor control are among the secondary endpoints. Based on the results of prior research it was calculated that 258 patients are needed in each treatment arm, assuming a power of 80%. Total accrual time is expected to take 60 months. An interim analysis will be performed to assess any clinically significant safety concerns and to determine whether there is evidence that up front surgery is clinically or statistically inferior to systemic therapy with respect to the primary endpoint.Discussion
The SUBMIT study is a randomized controlled trial that will provide evidence on whether or not surgery of the primary tumor in breast cancer patients with metastatic disease at initial presentation results in an improved survival.Trial registration
NCT01392586. 相似文献87.
Gastric Cancer Precursor Lesions and Helicobacter pylori Infection in Patients with Partial Gastrectomy for Peptic Ulcer 总被引:3,自引:0,他引:3
Giuliani A Caporale A Demoro M Benvenuto E Scarpini M Spada S Angelico F 《World journal of surgery》2005,29(9):1127-1130
The mucosa of the gastric stump is considered at greater risk of dysplastic and neoplastic changes than that of the intact
stomach. The combination of enteric reflux and Helicobacter pylori infection may have a synergistic damaging effect on the
mucosa of the gastric remnant, both producing and increasing mucosal proliferation. The aim of this study was to assess whether
the occurrence of H. pylori infection in the remnant mucosa of partially gastrectomized subjects for peptic ulcer disease is associated with an increase
of the mucosal precursor lesions of malignancy. A series of 151 subjects who underwent partial gastrectomy for peptic ulcer
disease were submitted to upper digestive endoscopy for long-term surveillance. Biopsy specimens of the gastric stump were
tested for the occurrence of H. pylori infection and for the presence of precancerous mucosal lesions. The prevalence of H. pylori colonization in the remnant stomach was less than 30% and similar in subjects with different time intervals between gastrectomy
and endoscopy. Age at surgery (χ2: p = 0.03) and H. pylori infection (χ2: p = 0.002) were significantly associated with the grading of mucosal lesions. The prevalence of normal mucosa was 10 times
higher in H. pylori-negative patients as in H. pylori-positive ones (22.0% vs. 2.4%), and the prevalence of intestinal metaplasia was four times higher in H. pylori-positive patients than in H. pylori-negative ones (19.6% vs. 4.6%). We concluded that H. pylori infection may play a causal role in the development of gastric lesions in the operated stomach. 相似文献
88.
Pasquale Mastroroberto Massimo Chello Francesco Onorati Attilio Renzulli 《European journal of cardio-thoracic surgery》2005,27(3):531-2; author reply 532
89.
Anna Linda Chiara Zuiani Viviana Londero Eleonora Di Gaetano Anna Dal Col Rossano Girometti Massimo Bazzocchi 《La Radiologia medica》2014,119(6):393-399
Purpose
This study was undertaken to evaluate whether magnetic resonance (MR) imaging is able to rule out malignancy in the case of BI-RADS 3 microcalcifications, providing a sufficient negative predictive value (NPV) for early work-up, and to reduce unnecessary stereotactically guided vacuum-assisted biopsy (SVAB) procedures.Materials and methods
We prospectively enrolled consecutive women with BI-RADS 3 microcalcifications, who subsequently underwent MR imaging and SVAB. The MR studies were reviewed according to the MR-BI-RADS classification system; lesions assessed as MR-BI-RADS 1 and 2 were considered negative for malignancy, categories MR-BI-RADS 3, 4 and 5 indicated malignant lesions. The presence of additional findings was recorded. Histologic analysis and follow-up were the reference standard. MR sensitivity, specificity, positive predictive value (PPV) and NPV were calculated.Results
The final population consisted of 71 lesions. Histologic analysis showed malignancy in six cases (malignancy rate 8 %). At MR analysis, 60 (85 %) lesions were considered negative for malignancy and 11 (15 %) malignant. Additional MR imaging findings were identified in 19 (27 %) patients, all corresponding to nonmalignant lesions. MR sensitivity was 33 %, specificity 86 %, PPV 18 % and NPV 93 %.Conclusions
Because of its relatively low NPV, MR imaging is not able to safely exclude malignancy in the case of BI-RADS 3 microcalcifications. The relatively high malignancy rate found in this study might support SVAB in the case of BI-RADS 3 microcalcifications. 相似文献90.
Maria Assunta Cova Fulvio Stacul Roberto Quaranta Pierpaolo Guastalla Guglielmo Salvatori Giuseppe Banderali Claudio Fonda Vincenzo David Massimo Gregori Antonio Alberto Zuppa Riccardo Davanzo 《European radiology》2014,24(8):2012-2022