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31.
This study measured the time course of psychophysical end-stopping and compared it with the time course of masking. For a 10' D6 target on an 18' D6 pedestal, two abutting end-zone masks (each 13.5' long) covering the filter end-zones reduce masking. This facilitatory 'end-stopping' effect was measured over a range of exposure durations and stimulus onset asynchronies (SOAs). We found that psychophysical end-stopping has a delayed onset which is around 70-100 ms after stimulus onset, in contrast to masking which is robust immediately after stimulus onset, suggesting intracortical feedback processes in the generation of psychophysical end-stopping. The development course of psychophysical end-stopping is relatively long and lasts for approximately 150-200 ms after stimulus onset, in contrast to that of masking which lasts for approximately 100-150 ms. Our results also showed that end-stopping occurs only when the center mask and the end-zone masks have sufficient temporal overlap, possibly indicating that the feedback process for generating end-stopping is triggered by the activation of the spatial filter center by the center mask. These results are in tune with current knowledge of intracortical feedback modulating activities of receptive fields, and have been incorporated into our model to describe the temporal dynamics within end-stopped spatial filters. 相似文献
32.
Strabismic amblyopes show losses in positional acuity that cannot be explained by their resolution or contrast sensitivities. One hypothesis for these losses is a reduction in the density of cortical neurons that are driven by the amblyopic eye (cortical undersampling). The question this study addressed was whether the foveal representation of the amblyopic eye is undersampled in the cortex of strabismic amblyopes. In order to assess spatial sampling psychophysically, we recorded the perceived orientation of a stationary grating as a function of grating orientation and frequency in three strabismic amblyopes. To ensure high retinal contrast, the grating was imaged on the fovea of each observer using a laser interferometer. We found that the strabismic amblyopes misperceived the orientation of the grating at spatial frequencies that are a factor of two to six lower than the sampling frequency of the foveal cones. Since the retina and LGN in strabismic amblyopes are presumably normal, this result suggests sparse cortical sampling in the foveal representation of the amblyopic eye. Undersampling by cortical neurons may contribute to the spatial distortions present in strabismic amblyopic eyes. 相似文献
33.
R Pregazzi C Bouchè G Ricci F G Toffoletti R Levi D'Ancona F Barciulli 《Minerva ginecologica》1991,43(7-8):335-339
This study concerns clinical data of 142 women, who were subjected to functional evaluation of perineum during the last part of pregnancy. The 16 cases characterized by synergic activation, during the examination of perineal muscles ("perineal testing"), of antagonist muscles ("inverted control"), were examined taking into account data regarding evolution of labour and perineal outcome. "Inverted control" seems to influence, in this study, length of the second stage and frequency of operative deliveries whereas we can't confirm the importance of this disorder within pathogenesis of perineal obstetric complications. 相似文献
34.
Minghetti L Greco A Cardone F Puopolo M Ladogana A Almonti S Cunningham C Perry VH Pocchiari M Levi G 《Journal of neuropathology and experimental neurology》2000,59(10):866-871
The levels of 2 arachidonic acid metabolites formed either by enzymatic activity of cyclooxygenase, i.e. prostaglandin E2 (PGE2), or by free radical-catalyzed peroxidation, i.e. F2-isoprostane 8-epi-prostaglandin F2alpha (8-epi-PGF2alpha), were measured in the CSF of subjects with sporadic and familial Creutzfeldt-Jakob disease (CJD) and in brain homogenates of scrapie-infected mice. The CSF levels of both metabolites were increased in sporadic CJD (n = 52) and familial CJD (n = 10) patients when compared with a group of patients with noninflammatory disorders. Similarly, PGE2 and 8-epi-PGF2alpha levels were higher in brain homogenates obtained from C57BL/6J mice infected with the ME7 scrapie strain than in brain homogenates from control animals. As PGE2 is 1 of the most abundant prostaglandins released during inflammation and 8-epi-PGF2alpha is a quantitative marker of lipid peroxidation, our results provide in vivo biochemical evidence for the occurrence of inflammation and oxidative stress in human and experimental transmissible spongiform encephalopathies (TSEs), a concept so far based mainly on histopathological and in vitro evidence. Interestingly, in sporadic CJD patients, high CSF levels of PGE2, but not 8-epi-PGF2alpha, correlated with short survival time, suggesting that the inflammatory response correlates with the clinical duration of disease. 相似文献
35.
S Gallus A Altieri C Bosetti S Franceschi F Levi E Negri L Dal Maso E Conti P Zambon C La Vecchia 《Annals of oncology》2003,14(2):209-213
BACKGROUND: Tobacco smoking is one of the main risk factors for oral, pharyngeal and oesophageal cancers in developed countries. Information on the role of the tar yield of cigarettes in upper digestive tract carcinogenesis is sparse and needs to be updated because the tar yield of cigarettes has steadily decreased over the last few decades. PATIENTS AND METHODS: We analysed two case-control studies, from Italy and Switzerland, conducted between 1992 and 1999, involving 749 cases of oral and pharyngeal cancer and 1770 controls, and 395 cases of squamous-cell oesophageal carcinoma and 1066 matched controls. Odds ratios (ORs) were estimated by unconditional multiple logistic regression models, including terms for age, sex, study centre, education and alcohol consumption. RESULTS: Based on the brand of cigarettes smoked for the longest time, the multivariate ORs for current smokers compared with never smokers were 6.1 for <20 mg and 9.8 for >or=20 mg tar for oral and pharyngeal neoplasms, and 4.8 and 5.4 for oesophageal cancer, respectively. For the cigarette brand smoked in the previous six months, the ORs for >or=10 mg compared with <10 mg were 1.9 for cancer of the oral cavity and pharynx and 1.8 for oesophageal cancer, after allowance for number of cigarettes and duration of smoking. CONCLUSIONS: The present study confirms the direct relationship between the tar yield of cigarettes and upper digestive tract neoplasms, and provides innovative information on lower tar cigarettes, which imply reduced risks compared with higher tar ones. However, significant excess risks were observed even in the lower tar category, thus giving unequivocal indications for stopping smoking as a priority for prevention of upper digestive tract neoplasms. 相似文献
36.
Ana Milojevi Marija Zdravkovi Milica Brajkovi Lidija Memon Vera Gardijan Jelena Veki Aleksandra Zeljkovi Aleksandra Stefanovi Marija Mihajlovi Jasmina Ivanievi Nataa Bogavac-Stanojevi Vojislav Radosavljevi Vesna Spasojevi-Kalimanovska Ana Nini 《Medical principles and practice》2022,31(3):293
ObjectivesObstructive sleep apnea (OSA) is a common condition closely related to obesity, insulin resistance, dyslipidemia, and cardiovascular disease. The aim of this study was to explore the possible relationship between OSA and proprotein convertase subtilisin/kexin type 9 (PCSK9).MethodsFull-night polysomnography was performed on 150 participants who were divided into three groups: controls, OSA patients on statin therapy, and OSA patients not on statin therapy. Biochemical markers, plasma low-density lipoprotein (LDL) and high-density lipoprotein (HDL) subclasses, and PCSK9 were determined.ResultsPCSK9 was highest in OSA patients on statins compared to the control group and to OSA patients not on statins (p = 0.036 and p = 0.039, respectively), after adjustment for body mass index (BMI). LDL diameter was greater in OSA patients not on statins compared to OSA patients on statins (p = 0.032). PCSK9 was highest in the group of patients with all three risk factors (diagnosed OSA, statins, BMI ≥25 kg/m<sup>2</sup>) compared to groups with no, one, and two risk factors (p = 0.031, p = 0.001, and p = 0.029, respectively). Presence of OSA, statin therapy, and BMI ≥25 kg/m<sup>2</sup> when combined were independently associated with higher levels of PCSK9 when adjusted for antihypertensive therapy, small dense LDL, and HDL 3c subclass (odds ratio = 2.849; interquartile range [1.026–7.912], p = 0.044).ConclusionStatin therapy was closely related to PCSK9. OSA along with obesity and statin use induces elevation of PCSK9. 相似文献
37.
Milica Zekovi Jelena Mileevi Marija Taki Marija Knez Ivana arac Agnes Kadvan Mirjana Gurinovi Marija Glibeti 《Nutrients》2022,14(15)
The Serbian Food Consumption Survey among 1–9-year-old-children was conceptualized and conducted in compliance with the principles, established protocols, and guidelines of the EU Menu project between 2017 and 2021. Valid data were collected for 576 individuals (290 1–3-year-old toddlers and 276 3–9-year-old children). Regardless of age and gender category, the majority (68.80%) of children had normal weights according to the Body Mass Index-for-age classification system. The median daily energy intake was 1406.71 kcal with no differences between the settlement types. The overall median contributions of carbohydrates, protein, and fat to the total energy intake were 47.54%, 14.06%, and 37.88%, respectively. The proportions of the macronutrient intake deviated from the dietary reference values with compliance to the recommendations being particularly poor for fat and fiber. The consumption of energy-dense food groups such as meat and meat products, fat and oil, sugar, and confections was more pronounced among older children. The survey results provide a valuable insight into the nutritional status and dietary habits of toddlers and children 1–9 years old living in Serbia. They may serve as an evidence platform for public health programs, a valuable asset for decision-makers, and a reliable reference to guide nutritional policies, diet monitoring, and interventions targeting this population group in the future. 相似文献
38.
Most midwives are aware of the need to collect clinical practice data and of its usefulness in supporting the care they provide, which contributes to healthy outcomes for mothers and babies. For the individual midwife, there is more than one easily accessible, standardized data collection instrument from which to choose. However, despite these choices, in an American College of Nurse-Midwives (ACNM) Division of Research (DOR) survey on midwifery clinical data collection (N = 263), the majority of member respondents (n = 135; 51%) reported using a self-designed data collection tool, and more than one-third did not know of the ACNM Nurse-Midwifery Clinical Data Sets (NMCDS). On a larger scale, the midwifery profession is also in need of an organized and consistent approach to data collection for the purpose of capturing midwifery practice and outcomes in order to provide data to support legislation, practice, and policy changes. However, the profession currently lacks a single common midwifery practice database. In order to facilitate data aggregation that captures a larger view of midwifery practice at the local, regional, and national levels, it is imperative that all midwives collect relevant data that are uniform and standardized, and that the midwifery professional organizations move forward with the development of a common electronic database. This article describes currently available data collection tools as well as their best uses, applications to practice, and future directions. 相似文献
39.
Itay Bar-Or Victoria Indenbaum Merav Weil Michal Elul Nofar Levi Irina Aguvaev Zvi Cohen Virginia Levy Roberto Azar Batya Mannasse Rachel Shirazi Efrat Bucris Orna Mor Alin Sela Brown Danit Sofer Neta S. Zuckerman Ella Mendelson Oran Erster 《Viruses》2022,14(6)
In this report, we describe a national-scale monitoring of the SARS-CoV-2 (SC-2) variant dynamics in Israel, using multiple-time sampling of 13 wastewater treatment plants. We used a combination of inclusive and selective quantitative PCR assays that specifically identify variants A19/A20 or B.1.1.7 and tested each sample for the presence and relative viral RNA load of each variant. We show that between December 2020 and March 2021, a complete shift in the SC-2 variant circulation was observed, where the B.1.1.7 replaced the A19 in all examined test points. We further show that the normalized viral load (NVL) values and the average new cases per week reached a peak in January 2021 and then decreased gradually in almost all test points, in parallel with the progression of the national vaccination campaign, during February–March 2021. This study demonstrates the importance of monitoring SC-2 variant by using a combination of inclusive and selective PCR tests on a national scale through wastewater sampling, which is far more amendable for high-throughput monitoring compared with sequencing. This approach may be useful for real-time dynamics surveillance of current and future variants, such as the Omicron (BA.1, BA.2) and other variants. 相似文献
40.
Cheryl Duzenli Elisa K. Chan Theodora Koulis Sheri Grahame Joel Singer David Morris Josslynn Spence Terry Lee Levi Burns Robert A. Olson 《Current oncology (Toronto, Ont.)》2022,29(7):4734
There has been an increasing interest in patient-reported outcome (PRO) measures in both the clinical and research settings to improve the quality of life among patients and to identify when clinical intervention may be needed. The primary purpose of this prospective study was to validate an acute breast skin toxicity PRO measure across a broad sample of patient body types undergoing radiation therapy. Between August 2018 and September 2019, 134 women undergoing adjuvant breast radiotherapy (RT) consented to completing serial PRO measures both during and post-RT treatment and to having their skin assessed by trained trial radiation therapists. There was high patient compliance, with 124 patients (92.5%) returning to the clinic post-RT for at least one staff skin assessment. Rates of moist desquamation (MD) in the infra-mammary fold (IMF) by PRO were compared with skin assessments completed by trial radiation therapists. There was high sensitivity (86.5%) and good specificity (79.4%) between PRO and staff-reported presence of MD in the IMF, and there was a moderate correlation between the peak severity of the MD reported by PRO and assessed by staff (rho = 0.61, p < 0.001). This prospective study validates a new PRO measure to monitor the presence of MD in the IMF among women receiving breast RT. 相似文献