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Objectives To evaluate uterine artery resistance during multiovulation induction in relation to the implantation rate in patients attendingin vitro fertilization (IVF) cycles.Patients Multiovulation induction for IVF was monitored by daily determination of the pulsatility index (PI) of the uterine arteries, obtained by a transvaginal probe (6.5 MHz) implemented with color-flow imaging. Doppler data were obtained from 5 days before hCG administration to the day of follicular aspiration. One IVF cycle was monitored in 70 patients. In 17 patients, 41 IVF cycles were monitored until a successful attempt occurred.Results In the 70 patients studied during one IVF attempt, the PI of the uterine arteries significantly varied (P < 0.001) in the different phases of the cycle. In the 24 patients who conceived, a significantly lower PI (P < 0.03) was found throughout the cycle. This result was mainly due to a highly significant difference of PI values observed the day after hCG administration (P < 0.005). In the 17 patients who conceived after 1 to 4 negativein vitro fertilizations, no significant difference in PI was observed in the uterine artery resistance in cycles in which implantation was or was not successful.Conclusions Uterine artery resistance varies significantly during phases of the induction therapy. Uterine artery resistance is lower throughout the course of multiovulation induction in patients with higher pregnancy rates. The PI on the day after hCG administration was the best index of pregnancy rate. Low uterine artery resistance was present even in negative attempts in patients who eventually achieved a successful implantation. PI values 3 can be considered a favorable prognostic factor for future IVF cycles.Presented at the 49th Annual Meeting of the American Fertility Society, Montreal, 1993 and the 50th Annual Meeting of the American Fertility Society, November 5–10, 1994, San Antonio, Texas.  相似文献   
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· Background: The aim of this study was to evaluate the focal electroretinogram (FERG), an objective indicator of outer retinal function, in nonexudative age-related macular degeneration (NE-AMD), and to compare FERG results with morphological lesions assessed by stereoscopic fundus photographs and fluorescein angiograms. · Methods: Twenty-five patients (25 eyes) with bilateral NE-AMD (visual acuity of the study eyes ≥0.4) as well as 10 age- and sex-matched control subjects (10 eyes) were evaluated. FERGs were recorded from the macular region (9°) in response to sinusoidal stimuli flickered at 32 Hz. Amplitude and phase angle of the Fourier-analyzed FERG fundamental component were measured. Fundus lesions were graded from color slides according to the Wisconsin age-related maculopathy grading system [15]. Fluorescein angiograms were evaluated by an image analysis technique to compute the area with pathological hyperfluorescence (associated with drusen and/or retinal pigment epithelial atrophy) within the macular (approximately 9°×9°) region. · Results: Compared to control eyes, NE-AMD eyes had a reduction in the mean FERG amplitude (57% loss, P<0.001) with no phase changes. Amplitudes of individual affected eyes were negatively correlated with either the Wisconsin grading score (r=–0.63, P<0.001) or the percentage area of pathological hyperfluorescence (r=–0.70, P<0.01). Eyes with minimal NE-AMD lesions (Wisconsin score ≤6) and normal acuity had a lower mean amplitude (47% loss, P<0.05) than that of control eyes. · Conclusions: The results indicate that, in NE-AMD, the FERG is altered in parallel with the extent and severity of fundus lesions. However, a functional impairment of outer macular layers, which is detected by FERG losses, could precede morphological changes typical of more advanced disease. Received: 6 March 1998 Revised version received: 5 June 1998 Accepted: 17 June 1998  相似文献   
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BACKGROUND: The relative contribution to the olfactory dysfunction of the lesions in the specific brain regions involved in olfaction compared with the lesions scattered all over the rest of the brain has not been fully clarified yet in patients with multiple sclerosis (MS). The concurrent use of Magnetic Resonance Imaging (MRI) and a standardized test of odor identification ability now permits to study the relation between smell loss and the extent of white matter abnormalities. METHODS: We tested the olfactory function of 40 patients with definite MS and of 40 age-sex- and smoking-habit-matched healthy controls by using the Cross Cultural Smell Identification Test. We measured also the lesion load on T2-weighted images in the inferior-frontal and temporal lobes and in the rest of the brain in MS patients. Therefore, we tried to correlate measures of lesion load and smell test scores. RESULTS: A robust correlation was demonstrated between MR measures of lesion load in the white matter of the olfactory brain region and smell loss (r=-0. 739, P<0.0001). A significant relationship has been found even after taking potential confounding factors, such as sex, age, disease duration, disability, anxiety and depression, into account (r=-0.90, P<0.0001). CONCLUSIONS: Our findings show, in MS patients with stable neurological impairment and no recent disease exacerbation, a correlation between smell loss and the lesion load in the regions of the brain involved in olfaction and support the theory that the extent and severity of MRI abnormalities in specific brain regions are related to the presence of selective neurologic and neuropsychologic impairment.  相似文献   
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Deep vein thrombosis results from the cooperative action of leukocytes, platelets, and endothelial cells. The proline-rich tyrosine kinase Pyk2 regulates platelet activation and supports arterial thrombosis. In this study, we combined pharmacological and genetic approaches to unravel the role of Pyk2 in venous thrombosis. We found that mice lacking Pyk2 almost completely failed to develop deep venous thrombi upon partial ligation of the inferior vena cava. Pyk2-deficient platelets displayed impaired exposure of phosphatidylserine and tissue factor expression by endothelial cells and monocytes was completely prevented by inhibition of Pyk2. In human umbilical vein endothelial cells (HUVEC), inhibition of Pyk2 hampered IL-1β-induced expression of VCAM and P-selectin, and von Willebrand factor release. Pyk2-deficient platelets showed defective adhesion on von Willebrand factor and reduced ability to bind activated HUVEC under flow. Moreover, inhibition of Pyk2 in HUVEC strongly reduced platelet adhesion. Similarly, Pyk2-deficient neutrophils were unable to efficiently roll and adhere to immobilized endothelial cells under venous flow conditions. Moreover, platelets and neutrophils from Pyk2-knockout mice showed defective ability to form heterogeneous aggregates upon stimulation, while platelet monocyte interaction occurred normally. Consequently, platelet neutrophil aggregates, abundant in blood of wild-type mice upon inferior vena cava ligation, were virtually undetectable in Pyk2-knockout mice. Finally, we found that expression of Pyk2 was required for NETosis induced by activated platelets. Altogether our results demonstrate a critical role of Pyk2 in the regulation of the coordinated thromboinflammatory responses of endothelial cells, leukocytes and platelets leading to venous thrombosis. Pyk2 may represent a novel promising target in the treatment of deep vein thrombosis.  相似文献   
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Despite the existence of an effective live-attenuated vaccine, measles can appear in vaccinated individuals. We investigated breakthrough measles cases identified during our surveillance activities within the measles/rubella surveillance network (MoRoNet) in Milan and surrounding areas (Northern Italy). Between 2017 and 2021, we confirmed measles virus (genotypes B3 or D8) infections in 653 patients and 51 of these (7.8%) were vaccinees. Among vaccinated individuals whose serum was available, a secondary failure was evidenced in 69.4% (25/36) of cases while 11 patients (30.6%) were non-responders. Non-responders were more frequently hospitalized and had significantly lower Ct values in both respiratory and urine samples. Median age and time since the last immunization were similar in the two groups. Importantly, we identified onward transmissions from vaccine failure cases. Vaccinees were involved in 20 outbreaks, in 10 of them they were able to transmit the virus, and in 8 of them, they were the index case. Comparing viral hemagglutinin sequences from vaccinated and non-vaccinated subjects did not show a specific mutation pattern. These results suggest that vaccination failure was likely due to the poor immune response of single individuals and highlights the importance of identifying breakthrough cases and characterizing their clinical and virologic profiles.  相似文献   
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The fused filament fabrication (FFF) process is widely used for producing prototypes and functional parts for diverse applications. While FFF is particularly attractive due to its cost-effectiveness, on the other hand, the fabricated parts have limitations in terms of large manufacturing time and reduced mechanical properties. The latter is strongly influenced by the fabrication process parameters, which affect the interlayer bonding and the adhesion between consecutive layers. Several works presented in the literature analysed the correlation between mechanical properties and process parameters. It was demonstrated that an increase in the fabrication feed rate causes slippage between filament and the feeding system, which leads to a decrease in the extruded material flow, and thus in part density. This work aims to investigate how the limitation of the slippage phenomenon affects the mechanical properties of parts fabricated using the FFF process. A prototype machine, equipped with a closed-loop control system on filament transport, was used to fabricate samples for tensile tests and dynamical mechanical analysis. Samples fabricated enabling the filament transport control showed an increase both in ultimate tensile strength and elongation at break for those fabricated with disabled control, whilst a decrease in stiffness was observed. In addition, the results showed that the use of a filament transport control system on a FFF machine increases the possibility of fabricating high value-added parts.  相似文献   
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Simple SummaryGlioblastoma is an aggressive brain tumor with a dismal prognosis. In a minority of cases, it presents with multiple lesions already at the time of diagnosis, affecting patients’ survival and treatment. Our retrospective study aims to increase the current understanding and define a treatment for this sub-entity, to improve patient survival. Chemoradiotherapy is a also safe and efficacy treatment in patients with multiple lesions. Survival advantages from extensive resection remain unclear.AbstractGlioblastomas with multiple foci at presentation (mGBMs) account for 2–35% of all GBMs. mGBMs have limited existing data and no standardized treatment. This study aims to determine their incidence, demographic and clinical features, outcome, and prognostic factors in terms of overall survival. We performed a monocentric retrospective study, reviewing patients treated at the Istituto Oncologico Veneto. Inclusion criteria were: new diagnosis of GBM and presence of multiple lesions on pre-treatment MRI. ECOG PS was used to evaluate clinical condition, RANO criteria for radiological assessment, and CTCAE v5.0 for treatment-related adverse events. The incidence of newly diagnosed mGBM was 7.2% and the study population consisted of 98 patients. Median age was 63 years, M:F ratio of 1.8:1, and a surgical approach was undertaken in 73 patients (mostly partial resection). MGMT was methylated in 47.5%, and 82 patients received active oncological treatment (65.9% radiotherapy plus temozolomide (RT + TMZ)). The disease control rate with RT + TMZ was 63%. Median OS of the entire study population was 10.2 months (95% CI 6.6–13.8), and median PFS was 4.2 months (95% CI 3.2–5.2). The ECOG PS, the extent of resection, and the RT + TMZ were significant prognostic factors in the univariate analysis for OS, but only the RT + TMZ was a significant independent OS predictor in the multivariate analysis (HR = 3.1, 95% IC 1.3–7.7, p = 0.014). The incidence of mGBM is not rare. RT + TMZ is confirmed to be an independent prognostic factor for survival and a safe and effective treatment. When feasible, RT + TMZ should be considered as a possible first-line treatment. The role of the extent of resection is still unclear.  相似文献   
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