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排序方式: 共有5579条查询结果,搜索用时 15 毫秒
81.
Piero Barbanti MD PhD Cinzia Aurilia MD Sabina Cevoli MD PhD Gabriella Egeo MD PhD Luisa Fofi MD Roberta Messina MD Antonio Salerno MD Paola Torelli MD Maria Albanese MD PhD Antonio Carnevale MD Francesco Bono MD Domenico D'Amico MD Massimo Filippi MD Claudia Altamura MD PhD Fabrizio Vernieri MD EARLY Study Group 《Headache》2021,61(9):1351-1363
82.
Piero Olliaro Luciano Lombardi Simona Frigerio Nicoletta Basilico Donatella Taramelli Diego Monti 《Ultrastructural pathology》2013,37(1):9-13
Hemozoin, the detoxification product of hemoglobin heme, piles up as electron-dense material in the food vacuole (FV) of intraerythrocytic malaria parasites (malaria pigment). In infected individuals, pigment is internalized by both circulating and resident phagocytes, thus modulating their functions. Synthetic beta-hematin, prepared in vitro from hematin (ferriprotoporphyrin IX hydroxide) in acidic condition, is spectroscopically identical to hemozoin. In this electron microscopy study, native and synthetic hemozoin also prove to be morphologically indistinguishable (large polygonal crystals with apparent transverse banding) and to undergo the same process when internalized by phagocytes (primarily a direct uptake of crystals, similar to what is described for asbestos fibers). On the contrary,whole parasites appear to follow a classical endocytic pathway. This suggests that there may be differences between the ingestion of free particles and whole parasites in terms of modulation of phagocytes' functions. 相似文献
83.
Daniele Recupero Lorenzo Daniele Caterina Marchiò Luca Molinaro Isabella Castellano Paola Cassoni Alberto Righi Filippo Montemurro Piero Sismondi Nicoletta Biglia Giuseppe Viale Mauro Risio Anna Sapino 《The Journal of pathology》2013,229(3):390-399
A subgroup of HER2‐overexpressing breast tumours co‐expresses p95 $^{{\rm{HER2}}}$ , a truncated HER2 receptor that retains a functional HER2 kinase domain but lacks the extracellular domain, thus impairing trastuzumab binding. We evaluated p95 $^{{\rm{HER2}}}$ expression in 99 frozen breast carcinoma samples by western blot analysis. The HER2‐positive cell line BT474 treated with pervanadate or pronase was used as a positive control for p95 $^{{\rm{HER2}}}$ expression. Immunohistochemistry was performed on parallel formalin‐fixed, paraffin‐embedded sections of the same case series using antibodies directed against either the intra‐ or extra‐cellular binding domain of HER2. In particular, biotinylated trastuzumab (BiotHER) was used to evaluate the binding capacity of the humanized antibody. To avoid a subjective evaluation of the score values and the percentage of immunostained cells, the slides were scanned and automatically analysed. The number of cases with HER2 overexpression (score 3+) and HER2 gene amplification was higher in the p185 $^{{\rm{HER2}}}$ ‐positive/p95 $^{{\rm{HER2}}}$ ‐positive samples than in the p185 $^{{\rm{HER2}}}$ ‐positive/p95 $^{{\rm{HER2}}}$ ‐negative group. Automated analysis confirmed a significantly higher percentage of 3+ scored cells in p95 $^{{\rm{HER2}}}$ ‐positive cases. Conversely, the percentage of 2+ scored cells was higher in p95 $^{{\rm{HER2}}}$ ‐negative cases. The status of the HER2 extracellular domain was then studied using flow cytometry on BT474 cells after pronase enzymatic digestion using trastuzumab and pertuzumab, while the presence of HER2‐HER3 dimers was studied using a proximity‐ligation assay. In vitro experiments showed that short‐term pronase digestion of BT474 cells produced two HER2 fragments (of 95 and 150 kDa, detectable in tissue specimens as well), increased the binding affinity of trastuzumab, reduced the rate of HER2–HER3 dimers, and did not interfere with pertuzumab‐binding capacity. In conclusion, the presence of p95 $^{{\rm{HER2}}}$ as detected by western blot analysis does not compromise the immunohistochemical detection of HER2. Our data suggest that a reduction of the receptor steric hindrance as induced by enzymatic shedding may facilitate the binding capacity of trastuzumab. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
84.
Ning Jiang Silvia Muceli Bernhard Graimann Dario Farina 《Medical & biological engineering & computing》2013,51(1-2):143-151
Myoelectric control has been extensively applied in multi-function hand/wrist prostheses. The performance of this type of control is however, influenced by several practical factors that still limit its clinical applicability. One of these factors is the change in arm posture during the daily use of prostheses. In this study, we investigate the effect of arm position on the performance of a simultaneous and proportional myoelectric control algorithm, both on trans-radial amputees and able-bodied subjects. The results showed that changing arm position adversely influences the performance of the algorithm for both subject groups, but that this influence is less pronounced in amputee subjects with respect to able-bodied subjects. Thus, the impact of arm posture on myoelectric control cannot be inferred from results on able-bodied subjects and should be directly investigated in amputee subjects. 相似文献
85.
Deepanker Tewari Fabio Del Piero Stephen Cieply Willard Feria Helen Acland 《Journal of virological methods》2013
Equine herpesvirus-1 (EHV-1) strains with a single point mutation at the 2254 nucleotide position with a G2254 constitution within the DNA polymerase gene are associated strongly with equine myeloencephalopathies. Infections with non-neuropathogenic EHV-1 strains without the G2254 nucleotide but with an A2254 nucleotide are associated less frequently with equine neurologic disease. A retrospective study utilizing DNA extracted from formalin fixed paraffin embedded tissues was conducted with real time PCR and pyrosequencing, to determine the infecting EHV-1 strains. Infection with EHV-1 A2254 and or G2254 strain was detected with real time PCR, and was confirmed with a rapid pyrosequencing technique. Pyrosequencing was useful in at least 2 cases where real time PCR was equivocal in determining the infecting EHV-1 strain type. The strain with G2254 mutation was detected in 9.4% of 21 studied abortion cases, and in 86.6% of 15 neurologic cases. 相似文献
86.
Jakob K. Anninga Piero Picci Marta Fiocco Herman M. J. A. Kroon Daniel Vanel Marco Alberghini Hans Gelderblom Pancras C. W. Hogendoorn 《Virchows Archiv : an international journal of pathology》2013,462(1):109-120
Osteosarcomas of hands or feet are rare, and seemingly these cases differ in presentation and behavior compared to those in usual locations. The clinico-pathological presentation of patients with osteosarcomas of the hand or foot was studied and compared with published cases. Forty osteosarcomas were identified among 4,221 cases, representing 0.95 % of all osteosarcomas. Thirty of these were well documented. Mean age at diagnosis was 43 years (hands) and 36 years (feet) and male–female ratio was 1.2:1 and 2.0:1, respectively. In the hand, 62 % of the osteosarcomas presented in the metacarpals and 23 % in the phalanges, and only two cases occurred in the carpal bones. Distribution in the foot was tarsal bones 56 %, metatarsal bones 33 %, and phalanges 11 %.Of the cases in the hand 54 % were of high grade and of those in the foot 71 %. Survival of osteosarcomas of the hand or foot was 81 %. Only patients with high-grade osteosarcoma died of the disease. Histological grade was the only significant variable related to survival. High-grade osteosarcoma of the hand or feet should be treated similar to those in conventional sites. Osteosarcomas of hands or feet are rare and in a relative high proportion are of low grade. Survival in high-grade cases is comparable to that in conventional sites. 相似文献
87.
Fiorenza Giganti Silvia Ramat Iole Zilli Sara Guidi Laura Maria Raglione Sandro Sorbi Piero Salzarulo 《Journal of sleep research》2013,22(2):197-200
Normal subjects show an increase of sleepiness in the morning, early afternoon and before sleep. In the advanced stages of Parkinson's disease (PD) the mean level of sleepiness is quite high, while with respect to healthy subjects it seems to be unchanged in the early stages. The aim of this study was to evaluate the time–course of the sleepiness level during the wakefulness period in untreated patients with early‐stage Parkinson's disease. Eighteen Parkinson's disease patients who had never been treated before with dopaminergic drugs (male = 9, female = 9, age: 68.39 ± 1.89, mean ± standard error) and 18 healthy subjects (male = 9, female = 9, age: 67.22 ± 1.98) were recruited for this study. All subjects underwent continuous actigraphic recording for three consecutive days, during which they also completed the Karolinska Sleepiness Scale (KSS) once an hour throughout wakefulness. Our results showed a higher level of sleepiness in the patients than the controls in the hours following awakening and in the early afternoon, specifically at 08:00 and 14:00 hours (08:00 hours, PD patients, KSS: 3 ± 0.3 versus healthy subjects, KSS: 2 ± 0.2, P < 0.05; 14:00 hours, PD patients, KSS: 4.4 ± 0.5 versus healthy subjects, KSS: 3 ± 0.3, P < 0.05). We suggest that some daytime hours are sensitive windows showing the first increase of sleepiness which will spread later to the whole daytime. 相似文献
88.
Dawn Peck Amy White Gisele Pino April Studinski Meghan Strenk Randi Gadea Jennifer Gannon Bryce Heese Esperanza Font-Montgomery Tracy Klug Jennifer Burton George Hoganson Devin Oglesbee Dimitar Gavrilov Dietrich Matern Kimiyo Raymond Piero Rinaldo Silvia Tortorelli 《Molecular genetics and metabolism》2021
89.
Alessandro Conforti Ilenia Di Cola Viktoriya Pavlych Piero Ruscitti Onorina Berardicurti Francesco Ursini Roberto Giacomelli Paola Cipriani 《Autoimmunity reviews》2021,20(2):102735
Rheumatoid arthritis (RA) is an inflammatory disease typically affecting the joints, but the systemic inflammatory process may involve other tissues and organs. Many extra-articular manifestations are recognized, which are related to worse long outcomes. Rheumatoid nodules are the most common extra-articular feature, found in about 30% of patients. Secondary Sjögren's syndrome and pulmonary manifestations are observed in almost 10% of patients, also in the early disease. Active RA with high disease activity has been associated with an increased risk of such features. Male gender, smoking habit, severe joint disease, worse function, high pro-inflammatory markers levels, high titer of rheumatoid factor, and HLA-related shared epitope have been reported as clinical predictors of occurrence of these rheumatoid complications. In addition, there is a little evidence deriving from randomized controlled trials in this field, thus the therapeutic strategy is mainly empiric and based on small case series and retrospective studies. However, considering that these extra-articular manifestations are usually related to the more active and severe RA, an aggressive therapeutic strategy is usually employed in view of the poor outcomes of these patients.The extra-articular features of RA remain, despite the improvement of joint damage, a major diagnostic and therapeutic challenge, since these are associated with a poor prognosis and need to be early recognized and promptly managed. 相似文献
90.
Farina Roberto Simonelli Anna Baraldi Andrea Pramstraller Mattia Minenna Luigi Toselli Luca Maietti Elisa Trombelli Leonardo 《Clinical oral investigations》2021,25(10):5897-5906
Clinical Oral Investigations - To evaluate yearly tooth loss rate (TLR) in periodontitis patients with different periodontal risk levels who had complied or not complied with supportive periodontal... 相似文献