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91.
92.
Objective: The purpose of this retrospective observational cohort study was to determine the impact of certain risk factors on fetal loss, after mid-trimester amniocentesis.

Material and methods: Six thousand seven-hundred and fifty-two (6752) consecutive amniocenteses with known pregnancy outcome performed during a 7-year period (2004–2010) were included in this study. Different maternal-, fetal- and procedure-related factors were evaluated in this study.

Results: During this 7-year period, 6752 cases who underwent amniocentesis, with complete data available were evaluated for the outcome and risk factors mentioned. Total fetal loss rate (FLR) up to the 24th week was 1.19%. Risk factors associated with increased risk of fetal loss after amniocentesis were maternal age (OR:2.0), vaginal spotting (OR:2.2) and serious bleeding (OR:3.5) during pregnancy, history of 2nd trimester termination of pregnancy (OR:4.0), history of more than three spontaneous (OR:3.0) or surgical first trimester abortions (OR:2.1), fibromas (OR:3.0) and stained amniotic fluid (OR:6.1).

Conclusions: Amniocentesis is a safe-invasive procedure for prenatal diagnosis with total FLR of 1.19% in our institution during the study period. The present study has emphasized the significance of certain risk factors for adverse outcome and therefore the need to individualize the risk.  相似文献   
93.
The Jefferson Scale of Empathy (JSE) is a broadly used instrument developed to measure empathy in the context of health professions education and patient care. Evidence in support of psychometrics of the JSE has been reported in health professions students and practitioners with the exception of osteopathic medical students. This study was designed to examine measurement properties, underlying components, and latent variable structure of the JSE in a nationwide sample of first-year matriculants at U.S. colleges of osteopathic medicine, and to develop a national norm table for the assessment of JSE scores. A web-based survey was administered at the beginning of the 2017–2018 academic year which included the JSE, a scale to detect “good impression” responses, and demographic/background information. Usable surveys were received from 6009 students enrolled in 41 college campuses (median response rate?=?92%). The JSE mean score and standard deviation for the sample were 116.54 and 10.85, respectively. Item-total score correlations were positive and statistically significant (p?<?0.01), and Cronbach α?=?0.82. Significant gender differences were observed on the JSE scores in favor of women. Also, significant differences were found on item scores between top and bottom third scorers on the JSE. Three factors of Perspective Taking, Compassionate Care, and Walking in Patient’s Shoes emerged in an exploratory factor analysis by using half of the sample. Results of confirmatory factor analysis with another half of the sample confirmed the 3-factor model. We also developed a national norm table which is the first to assess students’ JSE scores against national data.  相似文献   
94.
95.
The 3-D spatial and mechanical features of nano-topography can create alternative environments, which influence cellular response. In this paper, murine fibroblast cells were grown on surfaces characterized by protruding nanotubes. Cells cultured on such nano-structured surface exhibit stronger cellular adhesion compared to control groups, but despite the fact that stronger adhesion is generally believed to promote cell cycle progression, the time cells spend in G1 phase is doubled. This apparent contradiction is solved by confocal microscopy analysis, which shows that the nano-topography inhibits actin stress fiber formation. In turn, this impairs RhoA activation, which is required to suppress the inhibition of cell cycle progression imposed by p21/p27. This finding suggests that the generation of stress fibers, required to impose the homeostatic intracellular tension, rather than cell adhesion/spreading is the limiting factor for cell cycle progression. Indeed, nano-topography could represent a unique tool to inhibit proliferation in adherent well-spread cells.  相似文献   
96.
Arginine-rich protein motifs have been described as potent cell-penetrating peptides (CPPs) but also as rather specific ligands of the cell surface chemokine receptor CXCR4, involved in the infection by the human immunodeficiency virus (HIV). Polyarginines are commonly used to functionalize nanoscale vehicles for gene therapy and drug delivery, aimed to enhance cell penetrability of the therapeutic cargo. However, under which conditions these peptides do act as either unspecific or specific ligands is unknown. We have here explored the cell penetrability of differently charged polyarginines in two alternative presentations, namely as unassembled fusion proteins or assembled in multimeric protein nanoparticles. By this, we have observed that arginine-rich peptides switch between receptor-mediated and receptor-independent mechanisms of cell penetration. The relative weight of these activities is determined by the electrostatic charge of the construct and the oligomerization status of the nanoscale material, both regulatable by conventional protein engineering approaches.  相似文献   
97.
OBJECTIVES: Kinetic characterization of TEM-134, a new TEM-type extended-spectrum beta-lactamase variant isolated from Citrobacter koseri during an Italian nationwide survey. TEM-134 is a natural derivative of TEM-2 with the following substitutions: E104K, R164H and G238S. METHODS: Recombinant TEM-134 was purified from Escherichia coli HB101 (pMGP-134) by three chromatographic steps (cation-exchange chromatography, gel permeation and fast chromatofocusing). Steady-state kinetic parameters (K(m) and k(cat)) were determined by measuring substrate hydrolysis under initial rate conditions using the Hanes linearization of the Michaelis-Menten equation. Modelling was carried out using the software Modeller (version 9.1). RESULTS: TEM-134 hydrolysed with variable efficiency (k(cat)/K(m) ranging from 5 x 10(3) to 8.0 x 10(5) M(-1) . s(-1)) penicillins, narrow-spectrum cephalosporins, cefepime, cefotaxime, ceftazidime and aztreonam, which appeared to be the best substrate. Molecular modelling of the enzyme indicated that the R164H substitution may result in a compromised omega loop in TEM-134 and this may be responsible for its narrower spectrum of activity. CONCLUSIONS: Kinetic data and molecular modelling suggested that R164H has a mild detrimental effect on the global activity of the enzyme.  相似文献   
98.
IgG4-related aortitis is an inflammatory condition of the aorta, characterized by aortic wall thickening and periaortic soft-tissue involvement. Therefore, this condition can mimic an aortic intramural hematoma (IMH), due to similar radiological findings. We hereby report the case of an IgG4-related aortitis misdiagnosed as an IMH, associated with cerebral hemorrhage, possibly due to cerebral vascular system involvement.  相似文献   
99.
Anorectal melanoma is a rare cancer with a very poor prognosis. Symptoms on presentation include rectal bleeding, anal pain, an appreciable anorectal mass, change in bowel habits, pruritis, and tenesmus. Current surgical treatment options include abdominoperineal resection and wide local excision (WLE). However, recent reports suggest that WLE is adequate for disease control while minimizing the morbidity associated with surgery. We present a case of a 63 year old female with an initial diagnosis of an unspecified rectal tumour found to be anorectal melanoma.  相似文献   
100.
The 20th conference of the Society on NeuroImmune Pharmacology will be held March 26-29, 2014. It features the latest in research examining the intersection of neuroscience, immunology and pharmacology, relevant for human health and disease. Particular emphases are placed on HIV and other infectious diseases, and abused substances, including illicit drugs and alcohol.  相似文献   
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