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71.
BackgroundWe searched for differences in resting-state functional connectivity (FC) between brain networks and its relationship with the microstructure of the thalamus between migraine with pure visual auras (MA), and migraine with complex neurological auras (MA+), i.e. with the addition of at least one of sensory or language symptom.Methods3T MRI data were obtained from 20 patients with MA and 15 with MA + and compared with those from 19 healthy controls (HCs). We collected resting state data among independent component networks. Diffusivity metrics of bilateral thalami were calculated and correlated with resting state ICs-Z-scores.ResultsAs compared to HCs, both patients with MA and MA + disclosed disrupted FC between the default mode network (DMN) and the right dorsal attention system (DAS). The MA + subgroup had lower microstructural metrics than both HCs and the MA subgroup, which correlated negatively with the strength of DMN connectivity. Although the microstructural metrics of MA patients did not differ from those of HCs, these patients lacked the correlation with the strength of DAS connectivity found in HCs.ConclusionsThe present findings suggest that, as far as MRI profiles are concerned, the two clinical phenotypes of migraine with aura have both common and distinct morpho-functional features of nodes in the thalamo-cortical network.  相似文献   
72.
OBJECTIVES: To compare two different schedules of two different anthracycline-containing regimens, where length of treatment is modulated according to the international prognostic index (IPI) in patients with aggressive non-Hodgkin's Lymphoma (NHL). METHODS: In 1993 the Gruppo Italiano per lo Studio dei Linfomi (GISL) started a randomized 2 x 2 factorial phase III clinical trial for patients with newly diagnosed aggressive NHL comparing ProME(Epidoxorubicin)CE-CytaBOM (PE-C) to ProMI(Idarubicin)CE-CytaBOM (PI-C) and a fixed to a flexible treatment schedule where anthracycline dose was to be modulated according to observed hematological toxicity. Patients with low or low-intermediate IPI (IPI 0-2) and those with intermediate-high or high IPI (IPI 3-5) should receive six or eight courses, respectively. Involved-field radiotherapy was allowed for patients with initial bulky disease or with residual masses. RESULTS: Three hundred and fifty-six patients were registered into the study and randomized. Patients were well balanced among the four study arms in terms of clinical characteristics and prognostic factors. Three hundred and forty-five patients were available for evaluation of study endpoints. At the end of induction therapy complete remission rate was 61%, 5-year failure-free survival (FFS) rate was 40% and 5-year overall survival (OS) rate was 59%; no differences were observed according to treatment arms. Patients in the flexible arm received higher dose intensity of anthracycline (P < 0.001) with no apparent increase in toxicity. However, the flexible schedule was not superior to the fixed one. Patients with IPI 3-5 showed lower response rates (45% vs. 67%: P < 0.0001) and lower 5-year FFS (29% vs. 45%: P < 0.0001) compared to those with IPI 0-2. CONCLUSIONS: six courses of fixed or flexible PE-C or PI-C can determine a promising success rate in patients with advanced aggressive NHL with IPI 0-2, whereas the same regimens are less effective in patients with IPI 3-5, even if two additional courses are delivered. For the latter group of patients innovative approaches are warranted.  相似文献   
73.
The outcome of operations performed in different institutions or by different surgeons can hardly be compared if the operative methods are not standardized. Six different vaginal hysterectomy methods were studied. The steps common in all of them were defined. These steps were analyzed for optimal performance and sequence during the operation. The resultant modified method was subjected to a prospective randomized study, which showed that the operation time and the need for pain drugs were reduced. This method was introduced to several departments in different countries. The optimization and standardization of surgical methods are expected not just to improve the postoperative outcome, but also to enable a comparison between different departments and surgeons.  相似文献   
74.
It is well-known that a soap film spanning a looped wire can have the topology of a Möbius strip and that deformations of the wire can induce a transformation to a two-sided film, but the process by which this transformation is achieved has remained unknown. Experimental studies presented here show that this process consists of a collapse of the film toward the boundary that produces a previously unrecognized finite-time twist singularity that changes the linking number of the film’s Plateau border and the centerline of the wire. We conjecture that it is a general feature of this type of transition that the singularity always occurs at the surface boundary. The change in linking number is shown to be a consequence of a viscous reconnection of the Plateau border at the moment of the singularity. High-speed imaging of the collapse dynamics of the film’s throat, similar to that of the central opening of a catenoid, reveals a crossover between two power laws. Far from the singularity, it is suggested that the collapse is controlled by dissipation within the fluid film surrounding the wire, whereas closer to the transition the power law has the classical form arising from a balance between air inertia and surface tension. Analytical and numerical studies of minimal surfaces and ruled surfaces are used to gain insight into the energetics underlying the transition and the twisted geometry in the neighborhood of the singularity. A number of challenging mathematical questions arising from these observations are posed.  相似文献   
75.
Low-grade inflammation is a common feature of chronic kidney disease (CKD) and persistent systemic inflammation is thought to be a strong predictor of cardiovascular events. Inflammation plays a role in determining the serum albumin levels in haemodialysis patients (HD) independently of the nutritional status. Increased cardiovascular mortality in CKD has been associated with the increased incidence of obesity in uremic patients. Ingenbleek suggested a prognostic inflammation and nutritional index (PINI), based on serum albumin, pre-albumin, C-reactive protein, and alpha1 acid glycoprotein, to identify and to follow up acutely ill patients at risk of major complications. The aims of the present study were: to verify the incidence of Normal Weight Obese (NWO) syndrome; to evaluate by PINI the effect of 8 weeks acetyl salicylic (100 mg/die) and atorvastatin (10 mg/die) combined treatment on chronic inflammation in 52 selected HD patients. Laboratory evaluation, anthropometric and body composition measurements were detected. At baseline the 56.25% of non-obese, the 84.21% of pre-obese-obese, and the 41.17% of NWO women showed PINI values >1 (normal status PINI<1). After the pharmacological treatment, high significant (P<0.001) reduction in lipid profile, an elevated increase of HDL levels, and a significant reduction of inflammatory markers were obtained. Firstly, our results showed that ASA and atorvastatin combined treatment was effective in reducing inflammatory status in HD patients independently of body composition: at the end of the study only 7.49% of the patients exhibited PINI>1. Further studies will be necessary to understand the causes of inflammation in non-responder patients.  相似文献   
76.
CA 125 antigen was measured in amniotic fluid, maternal blood, cord blood, and fetal urine by a commercially available immunoradiometric assay kit. The amniotic fluid was obtained from 99 normal pregnancies at various gestational ages. The mean antigen levels were 29,676, 3350, and 1680 U/ml in amniotic fluid of the first, second, and third trimesters, respectively. In maternal blood, 12.5% of pregnant women in the first trimester of pregnancy showed elevated levels of CA 125 (65 to 100 U/ml). Late in gestation, CA 125 levels in cord blood and fetal urine were always less than 65 U/ml. Immunohistochemical study of CA 125 in fetal membranes, placenta, and decidua showed the presence of antigen only in the amnion. These results suggest that CA 125 is shed into amniotic fluid directly from the amniotic membrane.  相似文献   
77.
BACKGROUND AND OBJECTIVES: During the last decade an epidemiological association between hepatitis C virus (HCV) and B-cell lymphoproliferative disorders (B-LPD) has been reported; the same association has not been observed for Hodgkin's disease (HD). Hepatitis G virus (HGV) shares genetic and biological features with HCV, thus it might also be involved in lymphomagenesis. DESIGN AND METHODS: The aim of this study was to compare the prevalence of HCV and HGV infection in patients at diagnosis of B-LPD or HD. RESULTS: We tested 227 consecutive untransfused patients (127 with B-LPD and 100 with HD) and 110 healthy controls. The prevalence of HCV infection was significantly higher in B-LPD patients than in controls (17.3% vs. 1.8%, p<0.002 ), whereas it was the same in HD patients as in controls. In contrast, the prevalence of HGV was significantly higher in patients, both those with B-LPD (7.8% vs. 0.9%, p<0.03) and those with HD (13% vs. 0.9%, p<0.002), than in controls. Among the various B-LPD tested, HGV infection was more frequent in B-NHL (11.5%). INTERPRETATION AND CONCLUSIONS: Our data support the hypothesis that HGV infection may play a role in lymphomagenesis and that this role is different and separate from that of HCV.  相似文献   
78.
OBJECTIVE: The aim of this study was to measure the time-effect profiles of a once-daily administered valsartan/hydrochlorothiazide combination and amlodipine on blood pressure using various indices derived from 24-h ambulatory blood pressure (BP) monitoring. METHODS: Of the 310 randomized outpatients with uncomplicated mild-to-moderate primary hypertension, 259 (133 on valsartan/hydrochlorothiazide, 126 on amlodipine) were eligible for analysis. After a 2-week placebo wash-out period, the patients were randomly allocated to treatment with either valsartan 80 mg once daily (o.d.) or amlodipine 5 mg o.d. for 4 weeks; in the case of an unsatisfactory blood pressure response, the treatments could be respectively changed to the fixed combination of valsartan 80 mg plus hydrochlorothiazide 12.5 mg o.d. or amlodipine 10 mg o.d. for a further 8 weeks. The trough:peak ratio (global and individualized approaches) and smoothness index (i.e., the ratio between the average of the 24-hourly BP changes after treatment and the corresponding standard deviation) were calculated from 24-h ambulatory blood pressure recordings made after the placebo period and after 4 weeks and 12 weeks of active treatment. RESULTS: Both regimens effectively lowered systolic and diastolic ambulatory pressures after 4 weeks and 12 weeks (all P<0.001) but, among the responders, the valsartan/hydrochlorothiazide combination had a greater antihypertensive effect during the night-time hours after 12 weeks (P=0.03/0.02). In the responders, the placebo-adjusted, mean trough:peak ratios were 0.76/0.74 in the valsartan/hydrochlorothiazide group (n = 111) and 0.66/0.62 in the amlodipine group (n = 101). The corresponding global trough:peak ratios were 0.61/0.57 for the valsartan/hydrochlorothiazide combination and 0.56/0.56 for amlodipine. However, the between-group differences in individual or global trough:peak ratios were not significant. The smoothness index was slightly, but insignificantly, greater for valsartan/hydrochlorothiazide than for amlodipine in the responders and the groups as a whole. CONCLUSION: Valsartan/hydrochlorothiazide and amlodipine were equally effective in reducing ambulatory BP, but the valsartan/hydrochlorothiazide combination led to more homogeneous BP control during the inter-dosing interval. Trough:peak ratio and smoothness index did not reflect this finding accurately.  相似文献   
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