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排序方式: 共有1453条查询结果,搜索用时 15 毫秒
31.
32.
Breno José Acauan Filho Bartira Ercilia Pinheiro da Costa Patrícia Barcelos Ogando Matias Costa Vieira Ivan Carlos Antonello Carlos Eduardo Poli-de-Figueiredo 《Hypertension in pregnancy》2016,35(2):226-233
Objectives: To compare nitric oxide (NO) serum levels in women with and without preeclampsia. Methods: 106 women were classified into preeclampsia group (n = 40) and normotensive group (n = 66). NO content was measured in the serum. Clinical and laboratorial data were recorded for comparison. Results: Preeclampsia presented a significant increase in nitrate and NOx levels compared to the control group. Uric acid, gestational age, systolic and diastolic blood pressure, and creatinine showed correlation with nitrates and NOx. Conclusion: Increase of NO was observed in preeclampsia women. Failure in the mechanism of action, dependent on cyclic GMP, may justify this finding. 相似文献
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34.
Tereza Zelenková Maria Julia Mora Antonello A. Barresi Gladys Ester Granero Davide Fissore 《Journal of pharmaceutical sciences》2018,107(4):1157-1166
This work is focused on the synthesis of polycaprolactone nanoparticles, coated with chitosan, in a confined impinging jet reactor using the solvent displacement method. The role of the various reacting species was investigated, evidencing that a biocompatible polymer, for example, polycaprolactone, is required to support chitosan to obtain a monomodal particle size distribution, with low particle diameters. A surfactant is required to reduce the nanoparticle size (down to a mean diameter of about 260 nm) and obtain a positive zeta potential (about +31 mV), perfectly suitable for pharmaceutical applications. Different surfactants were tested, and Poloxamer 388 appeared to be preferable to polyvinyl alcohol. The effect of the concentration of Poloxamer 388 (in the range 0.5-5 mg mL?1) and of chitosan (in the range 1.5-5 mg mL?1) on both the mean particle size and zeta potential was also investigated, evidencing that chitosan concentration has the strongest effect on both parameters. Finally, the effect of solvent evaporation, quenching and feed flow rate was investigated, showing that the evaporation stage does not affect particle characteristics, quenching is required to avoid particle aggregation, and a minimum liquid flow rate of 80 mL min?1 is required in the considered reactor to minimize the particle size. 相似文献
35.
36.
Tappero Gianfranco Parente Renato Borghini Raffaele Trecca Antonello 《Techniques in coloproctology》2021,25(9):1093-1094
Techniques in Coloproctology - 相似文献
37.
Banu Murali Bindu Madhavan Vijaya Ramnath Devaraj Rajamani Emad Abouel Nasr Antonello Astarita Hussein Mohamed 《Materials》2022,15(3)
The present work aimed to investigate the dry sliding wear behaviors of hybrid polymer matrix composites made up of Kevlar, bamboo, palm, and Aloe vera as reinforcement materials of varying stacking sequences, along with epoxy as the matrix material. Three combinations of composite laminates with different stacking sequences such as AB, BC, and CA were fabricated by a vacuum-assisted compression molding process. The influence of composite laminates fabricated through various stacking sequences and dry sliding wear test variables such as load, sliding distance, and sliding velocity on the specific wear rate and co-efficient of friction were investigated. Experiments were designed and statistical validation was performed through response surface methodology-based D-optimal design and analysis of variance. The optimization was performed using grey relational analysis (GRA) to identify the optimal parameters to enhance the wear resistance of hybrid polymer composites under dry sliding conditions. The optimal parameters, such as composite combinations of CA, a load of 5 N, a sliding velocity of 3 m/s, and a sliding distance of 1500 m, were obtained. Furthermore, the morphologies of worn-out surfaces were investigated using SEM analysis. 相似文献
38.
Reading errors in patients with cerebellar vermis lesions 总被引:2,自引:0,他引:2
Dyslexia, both developmental and acquired, has been considered the result of cerebrocortical dysfunction, affecting the temporo-parieto-occipital
brain regions. However, dyslexia may involve abnormalities of the magnocellular component of the visual system, leading to
binocular instability or alterations of accommodation. To test the hypothesis of cerebellar involvement in the reading process
– justified by its emergent role in language and cognition – we studied 10 patients with cerebellar vermis/paravermis lesions
using reading tests and we compared the results with those produced by 10 normal volunteers. The data obtained demonstrate
an increased number of reading mistakes in the patient group, resulting from a possible alteration of the diffuse connection
system from the cerebellum to different cerebrocortical and subcortical structures. Acquired dyslexia due to cerebellar impairment
may be due to oculomotor alteration or, more subtly, to the intimate cerebellar-encephalic projections, connecting the cerebellum
to the attentive and alerting processes and to the language system. We discuss the data with an overview of literature.
Received: 22 May 2001, Received in revised form: 14 September 2001, Accepted: 25 September 2001 相似文献
39.
Trecca A Gai F Di Lorenzo GP Hreniuc H Pasciuto A Antonellis F Sperone M 《Chirurgia italiana》2004,56(1):31-36
Early endoscopic diagnosis of colorectal cancers is the best tool for the reduction of colorectal cancer mortality, but conventional colonoscopy seems unable to detect minor changes in the colorectal mucosa. The authors compare the results of conventional colonoscopy and chromoendoscopy plus magnifying endoscopy for the detection of colorectal lesions. This prospective study evaluated 995 consecutive selected patients. All patients with a previous diagnosis of colorectal polyps, inflammatory bowel disease, history of colorectal surgery, high coagulative risk or poor bowel preparation were excluded from the study. All examinations were performed by a single endoscopist. The authors compared the results of conventional endoscopy and chromoendoscopy with a 0.4% indigo carmine solution and magnifying endoscopy. At the end of each examination, data from ordinary and dye-spraying views were carefully recorded. A total of 202 protruding, 99 flat and 5 depressed lesions were detected. The incidence of high-grade dysplasia and early carcinoma was 9.9% for protruding lesions, 13.1% for flat lesions and 60% for depressed lesions. Chromoendoscopy revealed new neoplastic patterns not detectable at conventional endoscopy in 127 patients. This prospective study shows the high accuracy rate of chromoendoscopy for the detection of non-polypoid lesions. Chromoendoscopy could be used as a routine procedure in order to enhance the early diagnosis of colorectal cancers. 相似文献
40.
K-ras gene mutational analysis supports a monoclonal origin of biphasic pleomorphic carcinoma of the lung. 总被引:2,自引:0,他引:2
Giuseppe Pelosi Aldo Scarpa Michela Manzotti Giulia Veronesi Lorenzo Spaggiari Filippo Fraggetta Oscar Nappi Elvira Benini Felice Pasini Davide Antonello Antonio Iannucci Patrick Maisonneuve Giuseppe Viale 《Modern pathology》2004,17(5):538-546
We investigated 27 pleomorphic carcinomas of the lung for exon 1 K-ras gene mutations using polymerase chain reaction-single-strand conformation polymophism analysis and direct sequencing. All pleomorphic carcinomas were biphasic, that is, composed of an adeno-, squamous- or large-cell-carcinomatous component associated with a spindle- and/or giant-cell component. Of 27 cases, six (22%) showed K-ras codon 12 mutations, which is a figure higher than that previously reported on in pure sarcoma-like pleomorphic carcinomas. Five tumors displayed the same mutation in both the epithelial and the sarcomatoid components, whereas in one tumor the mutation was restricted to the epithelial component. All mutations occurred in smokers, and were transversions, including GGT (glycine) to TGT (cysteine) change in two cases, to GCT (alanine) in two and to GTT (valine) in two. No significant relationships were found between the occurrence and type of mutations and patients' survival or any other clinicopathological variable, suggesting that K-ras mutations are early events in the development of these tumors. Our results indicate that most, though not all, biphasic pleomorphic carcinomas of the lung are monoclonal in origin, and that cigarette smoking may have a causative role in the development of K-ras alterations in these tumors, as all mutations are transversions. 相似文献