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991.
Dyspnea is among the most frequent complaints in the elderly. The prevalence of comorbid medical conditions and the physiologic changes of aging present significant challenges in determining the cause. The initial approach to the elderly dyspneic patient mandates consideration of a broad range of diagnoses. Failure to diagnose life-threatening medical conditions presenting with dyspnea such as pulmonary embolus, acute coronary syndromes, congestive heart failure, asthma, obstructive pulmonary disease, pneumothorax, and pneumonia can lead significant morbidity and mortality. This article focuses on the rapid assessment and approach to the acutely dyspneic elderly patient. 相似文献
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995.
Ramos SG Barbosa GH Tavora FR Jeudy J Torres LA Tone LG Trad CS 《Journal of pediatric surgery》2007,42(5):e1-E4
An 8-year-old girl was evaluated for a mass in the left pulmonary lobe. Her clinical history was remarkable for an intermittent dry cough since the age of 2, with recurrent episodes of purulent sputum and fever. She underwent left lower lobectomy, which was found to be a bronchioloalveolar carcinoma arising in a type 1 congenital pulmonary airway malformation at pathologic examination. No additional therapies were undertaken. Two years after resection, imaging studies showed 5 contralateral pulmonary nodules suggestive of disseminated disease with a poor outcome. A review of presentation, treatment, and outcome of this association was made. 相似文献
996.
Mª Jos Gmez Ignacio Morn Carmen Torres Francisco Jos Esteban Lourdes de la Torre Antonio Cndido Antonio Maldonado Alberto Fernndez-Teruel Adolf Tobea Mª Dolores Escarabajal 《Neuroscience letters》2009,450(3):317-320
The goal of the present experiment was to study the performance of inbred Roman high- (RHA-I) and low- (RLA-I) avoidance rats in one-way avoidance learning and to relate the behaviour of the animals to cellular density in the basolateral amygdala (BLA), a brain region related to fear and anxiety. Thus, females from both strains were exposed either to 30 s or 1 s in the safe place as a function of experimental condition, until they reached five consecutive avoidance responses. Thereafter, the rats were perfused, and their brains sectioned in 40 μm coronal sections, stained with cresyl violet. The area (percentage of field) corresponding to the BLA structures was quantified by computerized-assisted image analysis. The results indicated that RLA-I showed a significantly poorer acquisition of the one-way avoidance task than did RHA-I rats, but only when safe time was the shortest (1 s). In addition, the number of trials needed to reach the behavioural acquisition criterion was negatively correlated with BLA cellular density in RLA-I rats. These data suggest the possibility of relating behavioural and neuro-anatomical indexes, enabling exploration of the biological basis of fear/anxiety behaviours. 相似文献
997.
Acosta Belsy Valdés Odalys Pi?ón Alexander Savón Clara Goyenechea Angel Gonzalez Grehete Gonzalez Guelsys Sarmiento Luis Más Pedro Guzmán María Guadalupe Llop Alina Perez Bre?a Ma Pilar Casas Inmaculada 《Archives of virology》2009,154(4):619-627
Adenoviruses are common pathogens that are responsible for a wide variety of infectious syndromes. The objectives of this
study were to identify and characterize members of different adenovirus species at the molecular level and to describe the
correlation between viruses and clinical syndromes during a period of 4 years. Between 2002 and 2006, 45 of 512 respiratory
specimens (8%) from patients with acute respiratory tract infection tested positive for adenovirus. Four adenovirus isolates
from samples sent for enterovirus isolation were also analyzed. This research identified 49 confirmed cases of human adenovirus
infection by PCR and/or viral culture. The most common diagnosis was upper respiratory infection (44%). Human adenovirus
D was the major species found (59%), followed by Human adenovirus
C (36%) and Human adenovirus
B (4%). Human adenovirus 5 was the major serotype found producing bronchiolitis, followed by human adenovirus 6. In patients
with upper respiratory infection, the major serotype found was human adenovirus 17. Viruses of the species Human adenovirus
D were identified in seven (77%) cases of acute febrile syndrome. Four isolates from clinical materials obtained from patients
with encephalitis, acute flaccid paralysis and meningoencephalitis were identified as belonging to the species Human adenovirus
D. Our data demonstrate a surprising result about the identification of an unusual association of viruses of the species Human adenovirus
D with different clinical syndromes. This observation could be evaluated as a possible indicator of the emergence of a novel
strain but further studies are required. 相似文献
998.
Faleh Tamimi Jesus Torres Uwe Gbureck Enrique Lopez-Cabarcos David C. Bassett Mohammad H. Alkhraisat Jake E. Barralet 《Biomaterials》2009,30(31):6318-6326
Onlay autografting is amongst the most predictable techniques for craniofacial vertical bone augmentation, however, complications related to donor site surgery are common and synthetic alternatives to onlay autografts are desirable. Recent studies have shown that the acidic calcium phosphates, brushite and monetite, are osteoconductive, osteoinductive and resorb faster in vivo than hydroxyapatite. Moreover, they can be 3D printed allowing precise host bone–implant conformation. The objectives of this study were to confirm that craniofacial screw fixation of 3D printed monetite blocks was possible and to compare the resulting vertical bone augmentation with autograft. 3D printed monolithic monetite onlay implants were fixed with osteosynthesis screws on the calvarial bone surface of New Zealand rabbits. After 8 weeks, integration between the implant and the calvarial bone surface was observed in all cases. Histomorphometry revealed that 42% of the monetite was resorbed and that the new bone formed within the implant occupied 43% of its volume, sufficient for immediate dental implant placement. Bone tissue within the autologous onlay occupied 60% of the volume. We observed that patterns of regeneration within the implants differed throughout the material and propose that this was due to the anatomy and blood supply pattern in the region. Rapid prototyped monetite being resorbable osteoconductive and osteoinductive would appear to be a promising biomaterial for many bone regeneration strategies. 相似文献
999.
Minimally invasive maxillofacial vertical bone augmentation using brushite based cements 总被引:1,自引:0,他引:1
Tamimi F Torres J Lopez-Cabarcos E Bassett DC Habibovic P Luceron E Barralet JE 《Biomaterials》2009,30(2):208-216
An ideal material for maxillofacial vertical bone augmentation procedures should not only be osteoconductive, biocompatible and mechanically strong, but should also be applied using minimally invasive procedures and remain stable with respect to the original bone surfaces. This way, implant exposure and infection might be reduced and good mechanical stability may be achieved. Calcium phosphate cements are proven biocompatible and osteoconductive materials that can be injected using minimally invasive procedures. Among these cements, brushite based cements have the added advantage of being biodegradable in vivo. Therefore, this material has the potential for use in the aforementioned procedures. An in vivo study was performed in rabbits to evaluate the potential use of brushite cements in minimally invasive maxillofacial vertical bone augmentation procedures. In this study, we injected self-setting brushite cements on the subperiosteal bone surface using a minimally invasive tunnelling technique. The cement pastes were stable on the bone surface and hardened soon after they were injected thereby negating the need for additional supports such as membranes or meshes. The animals were sacrificed 8 weeks after the intervention and histological observations revealed signs of successful vertical bone augmentation. Therefore, we have demonstrated a minimally invasive vertical bone augmentation procedure that is an attractive alternative to current surgical procedures in terms of increased simplicity, reduced trauma, and lower cost of surgery. 相似文献
1000.
José M. Cuevas Manuela Torres‐Puente Nuria Jiménez‐Hernández María A. Bracho Inmaculada García‐Robles Fernando Carnicer Juan del Olmo Enrique Ortega Fernando González‐Candelas Andrés Moya 《Journal of medical virology》2009,81(4):650-656
Hepatitis C virus (HCV) presents several regions involved potentially in evading antiviral treatment and host immune system. Two regions, known as PKR‐BD and V3 domains, have been proposed to be involved in resistance to interferon. Additionally, hypervariable regions in the envelope E2 glycoprotein are also good candidates to participate in evasion from the immune system. In this study, we have used a cohort of 22 non‐responder patients to combined therapy (interferon alpha‐2a plus ribavirin) for which samples obtained just before initiation of therapy and after 6 or/and 12 months of treatment were available. A range of 25–100 clones per patient, genome region and time sample were obtained. The predominant amino acid sequences for each time sample and patient were determined. Next, the sequences of the PKR‐BD and V3 domains and the hypervariable regions from different time samples were compared for each patient. The highest levels of variability were detected at the three hypervariable regions of the E2 protein and, to a lower extent, at the V3 domain of the NS5A protein. However, no clear patterns of adaptation to the host immune system or to antiviral treatment were detected. In summary, although high levels of variability are correlated to viral adaptive response, antiviral treatment does not seem to promote convergent adaptive changes. Consequently, other regions must be involved in evasion strategies likely based on a combination of multiple mechanisms, in which pools of changes along the HCV genome could confer viruses the ability to overcome strong selective pressures. J. Med. Virol. 81:650–656, 2009 © 2009 Wiley‐Liss, Inc. 相似文献