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排序方式: 共有1114条查询结果,搜索用时 203 毫秒
991.
Bain O Otranto D Diniz DG dos Santos JN de Oliveira NP Frota de Almeida IN Frota de Almeida RN Frota de Almeida LN Dantas-Torres F de Almeida Sobrinho EF 《Emerging infectious diseases》2011,17(5):867-869
A male nematode was extracted from iris fibers of a man from the Brazilian Amazon region. This nematode belonged to the genus Pelecitus but was distinct from the 16 known species in this genus. Similarities with Pelecitus spp. from neotropical birds suggested an avian origin for this species. 相似文献
992.
Objective: To evaluate the peri-implant hard tissue change at 6 and 12 months after implant placement between definitive abutment placed at the same time of implant surgery, never removing it, and healing abutment disconnected and reconnected three times until the placement of the final rehabilitation. Material and methods: Each partial edentulous patient could receive between 1 and 4 platform-switched implants in the posterior regions. If the implants had primary stability—implant stability quotient (ISQ) equal to or greater than 50, they were randomized to the test group with the abutment inserted at the same time of implant placement (DA) or to the control group, receiving a healing abutment (PA). At 6 and 12 months after surgery, data related with vertical bone level changes (primary outcome) and other clinical parameters (implant mobility, bleeding on probing, probing depth, plaque index) were assessed. Results: 53 implants were included in the trial and completed 12 months follow-up (overall survival rate: 100%). All implants achieved primary stability, with an average ISQ value of 80.9 on the day of surgery. From surgery to 6 months, the mean bone loss was 0.14 ± 0.18 mm for the DA group and 0.23 ± 0.29 mm for the PA group, without statistical significance difference. Between 6 and 12 months, the mean bone loss was 0.14 ± 0.21 mm for the DA group and 0.21 ± 0.27 mm for the PA group, also without statistical significance between the two groups. There were no statistically significant differences (p = 0.330) in total bone loss after 12 months between the control and the study groups. Conclusions: The one abutment one time protocol has at least an equivalent effect on the peri-implant bone level changes when compared with the use of healing abutments that are disconnected and reconnected at least three times. 相似文献
993.
Wound care has been clinically demanding due to inefficacious treatment that represents an economic burden for healthcare systems. In Europe, approximately 7 million people are diagnosed with untreated wounds, leading to a cost between 6.000€ and 10.000€ per patient/year. In the United States of America, 1.5 million people over 65 years old suffer from chronic wounds. A promising therapeutic strategy is the use of exogenous growth factors because they are decreased at the wound site, limiting the recovery of the skin. Insulin is one of the cheapest growth factors in the market able to accelerate the re-epithelialization and stimulate angiogenesis and cell migration. However, the effectiveness of topical insulin in wound healing is hampered by the proteases in the wound bed. The encapsulation into nanoparticles improves its stability in the wound, providing adhesion to the mucosal surface and allowing its sustained release. The aim of this review is to perform a standing point about a promising strategy to treat different types of wounds by the topical delivery of insulin-loaded nanocarriers. 相似文献
994.
995.
Costa LM Pereira JE Filipe VM Couto PA Magalhães LG Bulas-Cruz J Maurício AC Geuna S Varejão AS 《Reviews in the neurosciences》2010,21(6):487-497
The two-dimensional (2D) kinematic approach is by far the most popular technique in rat gait analysis. This is a simple inexpensive procedure, which requires only one camera to record the movement. However, maximal precision and accuracy of the kinematic values are expected when the experimental protocol includes a three-dimensional (3D) motion analysis methodology. Locomotor speed is a basic kinematic parameter that is often neglected in most studies of movement disorders and neurological diseases. Because locomotor speed can act as confounder for the interpretation of the obtained results we also focused our attention on the relation between speed and 3D hindlimb kinematics. Our experimental set-up consisted of a motion capture system with four CMOS cameras which allowed a non-invasive estimation of the instantaneous position of color markers in a 3D measurement volume. Data were recorded while rats walked at different treadmill speeds (30 vs 60 cm/s). For the first time we reported detailed kinematic data for the sagittal, coronal and transverse plane during treadmill locomotion in rats. Despite the overall time course patterns of the curves were identical, we found significant differences between values of joint angular motion at 30 and 60 cm/s at selected points of the step cycle. The adaptation to higher treadmill walking included greater joint angular excursions. The present report highlights the importance of walking speed when evaluating rat hindlimb kinematics during gait. Hopefully, this study will be useful in experimental data assessment when multiple gait abnormalities are expected to occur in all planes of motion. 相似文献
996.
Filipe Dantas-Torres Maria Stefania Latrofa Stefania Weigl Viviana Domenica Tarallo Riccardo Paolo Lia Domenico Otranto 《Parasitology research》2012,110(2):695-698
Hepatozoon canis is a common protozoan of dogs, being among the most prevalent tick-borne pathogens infecting dogs around the world. It is
primarily transmitted by Rhipicephalus sanguineus, the brown dog tick. In this study we tested ticks collected from dogs and from the environment in order to track the origin
of an outbreak of H. canis infection detected in October 2009 in a private dog shelter in southern Italy. Ticks from dogs (n = 267) were collected during the spring of 2009, whereas ticks from environment (n = 300) were found on sticky traps placed in the same shelter during the summer of 2009. All ticks were tested by PCR for
the detection of a H. canis 18S ribosomal RNA gene fragment. Four (1.5%, one female and three males) ticks collected from dogs were PCR positive. None
of the larvae collected from the environment were positive, but a relatively high infection rate (8.0%) was detected in nymphs.
These findings point out that dogs became infected during the summer, when ticks were abundant and highly infected by H. canis. Moreover, this study suggests that castor oil sticky traps might be useful to collect engorged immature ticks in highly
infested environments (e.g., dog shelters). This might be particularly interesting to evaluate the level of infection by certain
pathogens in free-ranging ticks R. sanguineus, as done in the present study. 相似文献
997.
LF Azevedo A Costa-Pereira L Mendon?a CC Dias JM Castro-Lopes 《The journal of pain》2012,13(8):773-783
A cross-sectional nationwide epidemiological study was performed in a random sample of the Portuguese adult population, aiming to describe the prevalence and impact of chronic pain (CP). The 5,094 participants were selected by random digit dialing, between January 2007 and March 2008, and estimates were adequately weighted for the population. Prevalence of CP was 36.7% (95% confidence interval [CI] [35.3-38.2]), based on the definition of the International Association for the Study of Pain. Recurrent or continuous pain was present in 85% of those with CP, and moderate-to-severe intensity and disability were present in 68 and 35%, respectively. Highest CP prevalence was observed among the elderly, retired, unemployed, and less educated. Highest disability was found in relation with family/home responsibilities, recreational activities, occupation/work, and sleep/rest; 13% reported a diagnosis of depression and 49% reported interference in their job. The main factors associated with disability were sex, pain intensity, and depression or depressive symptoms. CP is highly prevalent, causes high personal and social burden, and affects particularly the most vulnerable subgroups. Portugal, depending on CP definition, could be placed in the lower prevalence group in Europe. Improvement in pain intensity management and special attention to affective components of CP are recommended. PERSPECTIVE: In this cross-sectional nationwide epidemiological study, we showed that chronic pain is a significant problem that is present in 37% of the Portuguese adult general population, is associated with high personal, family, and social burden, and affects in particular the most vulnerable subgroups of the population. 相似文献
998.
Parkinson's disease (PD) is the second most common neurodegenerative disorder affecting about 1% of the population older than 60 years. Classically, PD is considered as a movement disorder, and its diagnosis is based on the presence of a set of cardinal motor signs that are the consequence of a pronounced death of dopaminergic neurons in the substantia nigra pars compacta. There is now considerable evidence showing that the neurodegenerative processes leading to sporadic PD begin many years before the appearance of the characteristic motor symptoms, and that additional neuronal fields and neurotransmitter systems are also involved in PD, including olfactory structures, amygdala, caudal raphe nuclei, locus coeruleus, and hippocampus. Accordingly, adrenergic and serotonergic neurons are also lost, which seems to contribute to the anxiety in PD. Non-motor features of PD usually do not respond to dopaminergic medication and probably form the major current challenge in the clinical management of PD. Additionally, most studies performed with animal models of PD have investigated their ability to induce motor alterations associated with advanced phases of PD, and some studies begin to assess non-motor behavioral features of the disease. The present review attempts to examine results obtained from clinical and experimental studies to provide a comprehensive picture of the neurobiology and current and potential treatments for anxiety in PD. The data reviewed here indicate that, despite their high prevalence and impact on the quality of life, anxiety disorders are often under-diagnosed and under-treated in PD patients. Moreover, there are currently few clinical and pre-clinical studies underway to investigate new pharmacological agents for relieving these symptoms, and we hope that this article may inspire clinicians and researchers devote to the studies on anxiety in PD to change this scenario. This article is part of a Special Issue entitled 'Anxiety and Depression'. 相似文献
999.
1000.
L Lins VJ de Carvalho FF de Almeida Rego R Azevedo S Kashima VN Gallazi MT Xavier B Galvão-Castro LC Alcantara 《Journal of medical virology》2012,84(9):1428-1436
Human T‐lymphotropic virus type 1 (HTLV‐1) is associated with adult T‐cell leukemia (ATL) and HTLV‐1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) and has also been implicated in several disorders, including periodontal disease. The proviral load is an important biological marker for understanding HTLV‐1 pathogenesis and elucidating whether or not the virus is related to the clinical manifestation of the disease. This study describes the oral health profile of HTLV‐1 carriers and HAM/TSP patients in order to investigate the association between the proviral load in saliva and the severity of the periodontal disease and to examine virus intra‐host variations from peripheral blood mononuclear cells and saliva cells. It is a cross‐sectional analytical study of 90 individuals carried out from November 2006 to May 2008. Of the patients, 60 were HTLV‐1 positive and 30 were negative. Individuals from the HTLV‐1 positive and negative groups had similar mean age and social‐economic status. Data were analyzed using two available statistical software packages, STATA 8.0 and SPSS 11.0 to conduct frequency analysis. Differences of P < 0.05 were considered statistically significant. HTLV‐1 patients had poorer oral health status when compared to seronegative individuals. A weak positive correlation between blood and saliva proviral loads was observed. The mean values of proviral load in blood and saliva in patients with HAM/TSP was greater than those in HTLV‐1 carriers. The HTLV‐1 molecular analysis from PBMC and saliva specimens suggests that HTLV‐1 in saliva is due to lymphocyte infiltration from peripheral blood. A direct relationship between the proviral load in saliva and oral manifestations was observed. J. Med. Virol. 84:1428–1436, 2012. © 2012 Wiley Periodicals, Inc. 相似文献