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51.
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Gerardo J. Ramírez-Nava Clara L. Santos-Cuevas Isaac Chairez Liliana Aranda-Lara 《Medical & biological engineering & computing》2018,56(7):1135-1148
The aim of this study was to characterize the in vivo volumetric distribution of three folate-based biosensors by different imaging modalities (X-ray, fluorescence, Cerenkov luminescence, and radioisotopic imaging) through the development of a tridimensional image reconstruction algorithm. The preclinical and multimodal Xtreme imaging system, with a Multimodal Animal Rotation System (MARS), was used to acquire bidimensional images, which were processed to obtain the tridimensional reconstruction. Images of mice at different times (biosensor distribution) were simultaneously obtained from the four imaging modalities. The filtered back projection and inverse Radon transformation were used as main image-processing techniques. The algorithm developed in Matlab was able to calculate the volumetric profiles of 99mTc-Folate-Bombesin (radioisotopic image), 177Lu-Folate-Bombesin (Cerenkov image), and FolateRSense? 680 (fluorescence image) in tumors and kidneys of mice, and no significant differences were detected in the volumetric quantifications among measurement techniques. The imaging tridimensional reconstruction algorithm can be easily extrapolated to different 2D acquisition-type images. This characteristic flexibility of the algorithm developed in this study is a remarkable advantage in comparison to similar reconstruction methods. 相似文献
53.
Víctor Fernández Ventureira Ignacio Ros Arnal Gerardo Rodríguez Martínez Beatriz García Rodríguez Ruth García Romero Eduardo Ubalde Sainz 《Anales de pediatría (Barcelona, Spain : 2003)》2021,94(6):359-365
IntroductionAlthough changes in liver function tests can be non-specific in numerous clinical conditions, they can be the first sign of a potentially serious disease in an asymptomatic patient.Material and methodsRetrospective cohort study, performed by reviewing the records of children of a reference hospital central laboratory with alanine aminorransferase enzyme (ALT) elevation during a 6 month aleatory period.Results572 blood tests with serum ALT elevation corresponding to 403 patients had been assessed during the period studied. 98 patients were excluded for presenting abnormal liver test before the study period of comorbidity that could produce ALT elevation. The remaining 305 patients, 22.6% were diagnosed with a medical condition during the first blood test that explained the ALT elevation, although only 33.3% of them were followed up until verifying their normalization. Final study sample consists of 236 patients with abnormal liver test without apparent liver disease. Adequate follow-up was found only in 29% of them. From this group, 9 patients (13%) were diagnosed with liver disease. The rest of the sample were not properly monitored. In patients with higher serum ALT levels, follow-up was early and more appropiate.ConclusionsIn our area, most children without apparent liver disease are no properly monitored. Therefore, an opportunity to diagnosis and treat a potential liver disease was lost in a great number of children. All children with unexplainedhypertransaminasaemia must be studied. 相似文献
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Susanna Annibali MD DDS Isabella Bignozzi DDS Gerardo La Monaca DDS PhD Maria Paola Cristalli DDS PhD 《Clinical implant dentistry and related research》2012,14(1):3-40
Purpose: The purpose of this study was to review the reported evaluation criteria of the aesthetic result in oral implant rehabilitation. Materials and Methods: A literature search of MEDLINE, the Cochrane Collaboration, and EMBASE was performed to retrieve studies published between January 1990 and December 2008 using the following key words: “dental implants,”“clinical trial,” and “aesthetic index” (and their synonyms). A manual search of the literature published in the same period was also carried out using the following publications: Clinical Oral Implant Research, The International Journal of Oral and Maxillofacial Implants, and The International Journal of Periodontics and Restorative Dentistry. The inclusion criteria of the published studies were the following: human clinical trial, oral implant rehabilitation, at least 10 implants, at least 6 months of follow‐up from insertion of the prosthesis, and evaluation of the aesthetic result by means of an index. Results: The literature search revealed 650 relevant bibliographic references, of which 89 were selected for further analysis. A final total of 29 articles fulfilled the inclusion criteria; these included 10 retrospective case series, 11 prospective case series, 1 retrospective controlled clinical trial, 1 prospective controlled clinical trial, and 6 randomized controlled clinical trials. In general, evaluations of aesthetic results appear only in the more recent studies and refer mostly to implant rehabilitation in the maxillary anterior zone; the index used, in most cases, was the Papilla Index of Jemt. Conclusions: Although there appears to be a growing interest in aesthetics in dental implantology, there are as yet no universally accepted evaluation criteria of the aesthetic result. Therefore, further research is necessary to establish a common, complete, and reproducible index for the evaluation of aesthetic outcome that can add in the success criteria for implant therapy in the maxillary and mandibular anterior areas. 相似文献
56.
Repeatability of ectopic beats from 48‐hr ambulatory electrocardiography: The Atherosclerosis Risk in Communities (ARIC) Study 下载免费PDF全文
57.
Sunday A. Abiria Thomas V. Williams Alexander L. Munden Vandana K. Grover Ato Wallace Christopher J. Lundberg J. Gerardo Valadez Michael K. Cooper 《Journal of neuro-oncology》2014,117(2):243-251
DNA methylation plays an important role in cancer biology and methylation events are important prognostic and predictive markers in many tumor types. We have used methylation-specific multiplex ligation-dependent probe amplification to survey the methylation status of MGMT and 25 tumor suppressor genes in 73 glioblastoma cases. The data obtained was correlated with overall survival and response to treatment. The study revealed that methylation of promoter regions in TP73 (seven patients), THBS1 (eight patients) and PYCARD (nine patients) was associated with improved outcome, whereas GATA5 (21 patients) and WT1 (24 patients) promoter methylation were associated with poor outcome. In patients treated with temozolomide and radiation MGMT and PYCARD promoter methylation events remained associated with improved survival whereas GATA5 was associated with a poor outcome. The identification of GATA5 promoter methylation in glioblastoma has not previously been reported. Furthermore, a cumulative methylation score separated patients into survival groups better than any single methylation event. In conclusion, we have identified specific methylation events associated with patient outcome and treatment response in glioblastoma, and these may be of functional and predictive/prognostic significance. This study therefore provides novel candidates and approaches for future prospective validation. 相似文献
58.
Mathematical modeling of the electrical activity of the pancreatic β-cell has been
extremely important for understanding the cellular mechanisms involved in
glucose-stimulated insulin secretion. Several models have been proposed over the last 30
y, growing in complexity as experimental evidence of the cellular mechanisms involved has
become available. Almost all the models have been developed based on experimental data
from rodents. However, given the many important differences between species, models of
human β-cells have recently been developed. This review summarizes how modeling of
β-cells has evolved, highlighting the proposed physiological mechanisms underlying
β-cell electrical activity. 相似文献
59.
Susanna Annibali MD DDS Gerardo La Monaca DDS PhD Marco Tantardini DDS & Maria Paola Cristalli DDS PhD 《Journal of prosthodontics》2009,18(2):177-183
In prosthetically guided implantology, where ideal placement of implants is determined by the definitive restoration, the use of a radiographic/surgical template plays an essential role. This article describes how to fabricate a radiographic/surgical template to be used for radiographic diagnosis of the selected implant sites and as a guide during surgery for the insertion of the implant with correct angulation. 相似文献
60.
José Gerardo González-González Leonardo G. Mancillas-Adame Mercedes Fernández-Reyes† Minerva Gómez-Flores† Fernando Javier Lavalle-González Jorge Ocampo-Candiani† Jesús Zacarías Villarreal-Pérez 《Clinical endocrinology》2009,71(4):494-499
Background Epidemiological studies have associated androgenetic alopecia (AGA) with severe young-age coronary artery disease and hypertension, and linked it to insulin resistance. We carried out a case–control study in age- and weight-matched young males to study the link between AGA and insulin resistance using the homeostasis model assessment of insulin resistance (HOMA-IR) index or metabolic syndrome clinical manifestations.
Methods Eighty young males, 18–35 years old, with AGA ≥ stage III in the Hamilton–Norwood classification, and 80 weight- and age-matched controls were included. Alopecia, glucose, serum insulin, HOMA-IR index, lipid profile and androgen levels, as well as metabolic syndrome criteria, were evaluated.
Results The HOMA-IR index was significantly higher in cases than controls. Nonobese cases had a higher mean diastolic blood pressure and a more frequent family history of AGA than nonobese controls. A borderline difference in the HOMA-IR index was found in obese AGA cases vs. obese controls [ P = 0·055, 95% confidence interval (CI) 2·36–4·20 vs. 1·75–2·73]. Free testosterone values were significantly higher in controls than cases, regardless of body mass index (BMI). A statistically significant additive effect for obesity plus alopecia was found, with significant trends for insulin, the HOMA-IR index, lipids and free testosterone when BMI and alopecia status were used to classify the participants.
Conclusions Our results support the recommendation for assessing insulin resistance and cardiovascular-related features and disorders in all young males with stage III or higher AGA, according to the Hamilton–Norwood classification. 相似文献
Methods Eighty young males, 18–35 years old, with AGA ≥ stage III in the Hamilton–Norwood classification, and 80 weight- and age-matched controls were included. Alopecia, glucose, serum insulin, HOMA-IR index, lipid profile and androgen levels, as well as metabolic syndrome criteria, were evaluated.
Results The HOMA-IR index was significantly higher in cases than controls. Nonobese cases had a higher mean diastolic blood pressure and a more frequent family history of AGA than nonobese controls. A borderline difference in the HOMA-IR index was found in obese AGA cases vs. obese controls [ P = 0·055, 95% confidence interval (CI) 2·36–4·20 vs. 1·75–2·73]. Free testosterone values were significantly higher in controls than cases, regardless of body mass index (BMI). A statistically significant additive effect for obesity plus alopecia was found, with significant trends for insulin, the HOMA-IR index, lipids and free testosterone when BMI and alopecia status were used to classify the participants.
Conclusions Our results support the recommendation for assessing insulin resistance and cardiovascular-related features and disorders in all young males with stage III or higher AGA, according to the Hamilton–Norwood classification. 相似文献