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961.
A forelimb of a new sauropod dinosaur (Angolatitan adamastor n. gen. et sp.) from the Late Turonian of Iembe (Bengo Province) represents the first dinosaur discovery in Angola, and is one of the few occurrences of sauropod dinosaurs in sub-Saharan Africa collected with good chronological controls. The marginal marine sediments yielding the specimen are reported to be late Turonian in age and, thus it represents a non-titanosaurian sauropod in sub-Saharan Africa at a time taken to be dominated by titanosaurian forms. Moreover, Angolatitan adamastor is the only basal Somphospondyli known in the Late Cretaceous which implies in the existence of relict forms in Africa.  相似文献   
962.
Agronomic efficiency of intercropping tomato and lettuce   总被引:1,自引:0,他引:1  
Four experiments were carried out at the S?o Paulo State University, Brazil, with the aim of determining the agronomic viability of intercropping tomato and lettuce, under greenhouse conditions. The studied intercropping systems were established by transplanting lettuce at 0, 10, 20 and 30 days after transplanting (DAT) tomato and by transplanting tomato at 0, 10, 20 and 30 DAT lettuce. Intercropped tomato and lettuce were evaluated during two seasons and compared to their sole cropping. The experimental design was a randomized complete block with nine treatments. The productivity and the classification of the tomato fruits were not influenced by having lettuce intercropped with it, but lettuce production was lowered when tomato was intercropped with it. The longer the delay in lettuce transplanting, the greater the reduction in its productivity. There was an effect of cropping season on the extent of the agronomic advantage of intercropping over sole cropping. In the first cropping season, intercropping established by transplanting lettuce during the interval between 30 days before up to 20 DAT tomato yielded land use efficiency (LUE) indices of 1.63 to 2.22. In the second period, intercropping established with the transplanting of lettuce up to 30 days before tomato yielded LUE indices of 1.57 to 2.05.  相似文献   
963.
The authors present a solution for motion preservation in severe wrist arthritis with intercarpal involvement. Acellular dermal allograft is used as an interposition arthroplasty in these situations, rather than local tissue flaps such as previously described. Proximal row carpectomy has been shown to be one of the most successful procedures to correct chronic destructive arthritis in the wrist, keeping useful motion. Traditionally, a contraindication for proximal row carpectomy includes an arthritis that invades the lunate-capitate joint. The authors describe a technique to extend the traditional indications by covering the eroded articular surfaces with dermal allograft scaffold.  相似文献   
964.
Customized glass fiber posts that is well adjusted into the root canal and have mechanical properties similar to those of dentin may be a suitable treatment for severely compromised endodontically treated teeth. This article reports a 3-year follow up of severely damaged endodontically treated teeth restored with unidirectional fiber glass customized post and core system instead of a conventional fiber post. The fabrication of this glass fiber customized post is a simple technique, providing an increased volume of fibers into the root canal, and an adequate polymerization of the post-core system. Over a three-year period, the treatments demonstrated good clinical and radiographic characteristics, with no fracture or loss of the post and/or crown. This technique can be considered effective, less invasive, and suitable for restore endodontically treated teeth.  相似文献   
965.

Introduction

Images of oral lesions can look so exceptionally similar that a diagnosis hypothesis could be difficult. Lesions mimicking apical periodontitis must be considered when making a differential diagnosis. Intraosseous lipoma is a rare benign tumor of low incidence among all bone tumors, and therefore few cases have been reported in the literature.

Methods and Results

A case of intraosseous lipoma associated with the distobuccal root of tooth #1 in a 39-year-old woman is described. The dental general practitioner did not perceive anything of note in terms of the radiographic aspect, so consequently the periapical lesion went unnoticed. However, after tooth extraction, a different feature was noticed in the surgical specimen. The lesion associated to the roots of tooth #1 was surrounded by soft tissue forming a fibrous capsule (10 mm in diameter). A histopathologic examination showed an area of bone of lamellar aspect surrounding a central area of fat tissue diagnosed as intraosseous lipoma. This type of lesion is asymptomatic, and its etiology is unclear.

Conclusions

Intraosseous lipoma should be considered in the differential diagnosis of other jaw lesions. A histologic examination is mandatory for the diagnosis, because this lesion is characterized by bone of lamellar aspect surrounding a central area of fat tissue. The treatment chosen in this case was surgical excision, and the outcome was favorable.  相似文献   
966.
Belo Horizonte, the capital of the southeastern state of Minas Gerais, Brazil, and the fourth-largest city in the country, has the highest incidence of human visceral leishmaniasis (VL) together with a high prevalence of canine VL. The Northeast Sanitary District (NSD) of Belo Horizonte has the largest historical average of human VL cases in the metropolitan region, and is classified as a priority area for epidemiological and entomological monitoring of the disease. The objectives of the present study were to determine the seasonal variation in phlebotomine fauna and to describe the environmental situations in the NSD through characterization of peri-domiciles and application of geographical information system analysis. Entomological captures were performed every two weeks during the period July 2006 to June 2007 using HP light traps placed at 16 locations where cases of human VL had been reported in 2005. The environmental characterization of these locations was accomplished using forms and photographic images. Spatial analyses was used to determine the influence of vegetation, hydrography, altitude and pockets of poverty on the occurrence of cases of human and canine VL, and of phlebotomine vectors. A total of 633 phlebotomines belonging to the subtribes Psychodopygina and Lutzomyina were captured and, of these, 75% were identified as Nyssomyia whitmani and 11% as Lutzomyia longipalpis. The majority of the studied peri-domiciles presented inadequate hygienic conditions that would favor the development of phlebotomines. No significant correlations could be established between biogeographical aspects and either the incidence of human and canine VL or the occurrence of phlebotomines. The proximity of areas with vegetation, villages, slums and open watercourses exerted little influence on the incidence of VL. These findings reinforce the urbanization of the VL profile since the disease occurred in locations where conditions that have been classically related to its prevalence were not present. The results reported herein will be important for implementing measures against VL in the study area.  相似文献   
967.
Malaria and severe pneumonia in hospitalized young children may show striking clinical similarities, making differential diagnosis challenging. We investigated ways to increase diagnostic accuracy in patients hospitalized with clinical symptoms compatible with malaria and severe pneumonia, in an area with high a prevalence of infection with human immunodeficiency virus. A total of 646 children admitted at the Manhiça District Hospital in Manhiça, Mozambique who met the World Health Organization clinical criteria for severe pneumonia and malaria were recruited for 12 months and thoroughly investigated to ascertain an accurate diagnosis. Although symptom overlap between malaria and severe pneumonia was frequent among hospitalized children, true disease overlap was uncommon. Clinical presentation and laboratory determinations were ineffective in reliably distinguishing between the two diseases. Infection with human immunodeficiency virus differentially influenced the epidemiology and clinical presentation of these two infectious diseases, further challenging their discrimination on clinical grounds, and having a greater impact on the current burden and prognosis of severe pneumonia.  相似文献   
968.

Objective

Chemical solutions have been widely used for disinfection of dentures, but their effect on color stability of denture tooth acrylic resins after repeated procedures is still unclear. The aim of this in vitro study was to evaluate whether repeated cycles of chemical disinfectants affected the color stability of two denture tooth acrylic resins.

Material and Methods

Sixty disc-shaped specimens (40 mm x 3 mm) were fabricated from two different brands (Artiplus and Trilux) of denture tooth acrylic resin. The specimens from each brand (n=30) were randomly divided into 6 groups (n=5) and immersed in the following solutions: distilled water (control group) and 5 disinfecting solutions (1% sodium hypochlorite, 2% sodium hypochlorite, 5.25% sodium hypochlorite, 2% glutaraldehyde, and 4% chlorhexidine gluconate). Tooth color measurements were made by spectrophotometry. Before disinfection, the initial color of each tooth was recorded. Further color measurements were determined after subjecting the specimens to 7, 21, 30, 45, 60, and 90 immersion cycles in each tested solution. Color differences (ΔE*) were determined using the CIE L*a*b* color system. Data were analyzed using two-way repeated measures analysis of variance (ANOVA) followed by Tukey tests. The significance level was set at 5%.

Results

There were statistically significant differences in ΔE* among the 5 disinfectants and water during the 90 cycles of immersion for both denture tooth acrylic resins. Distilled water promoted the greatest color change in both denture tooth acrylic resins, nevertheless none of tested disinfectants promoted ΔE* values higher than 1.0 on these acrylic materials during the 90 cycles of disinfection.

Conclusions

Repeated immersion cycles in disinfecting solutions alter ∆E* values, however these values do not compromise the color of the tested denture tooth acrylic resins because they are imperceptible to the human eye.  相似文献   
969.
The aim of the present study was to analyze dental research trends in Brazil over the past nine years. All abstracts presented at the 26th Annual Meeting of the Brazilian Society for Dental Research in 2009 (n = 2648) were classified based on field of knowledge, home institution and geographic region. Data were compared with those previously published based on abstracts presented at various meetings. Between 2001 and 2006, five fields of knowledge had a greater than 10% representation among the total number of studies. These fields included restorative dentistry/dental materials (RD/DM), periodontics, endodontics, pediatric dentistry and population-based oral health. In 2009, only RD/DM maintained a greater than 10% proportion of meeting abstracts, and basic fields comprised the second position among those fields with greater representation (9.8%). The majority of research studies were performed at public institutions, and the number of abstracts per state increased significantly in 2009 (Wilcoxon test, p < 0.001). The southeastern region of Brazil submitted the greatest number of abstracts; however, other regions also demonstrated increased participation in research (11%). The percentage distribution of abstracts between states remained constant (Wilcoxon test, p = 0.255; r s = 0.873). The results of the present study suggest a slight shift in the scientific research profile in Brazilian dentistry: fields related to professional disciplines have declined in relative research participation, while increasing interest has been observed in basic fields and new specialties.  相似文献   
970.
Five multidrug-resistant nonclonally related Enterobacteriaceae isolates were recovered in Belgium in 2010 from three patients who had been hospitalized in Pakistan, Montenegro, and Serbia/Kosovo. New Delhi metallo-β-lactamase (NDM-1) was detected in each of the isolates in addition to several extended-spectrum β-lactamases (CTX-M-15, SHV-12), plasmidic cephalosporinases (CMY-16, CMY-58), rRNA methylases (ArmA, RmtB), and Qnr genes (qnrA6, qnrB1, qnrB2). One patient died from uncontrolled sepsis, while the two others recovered. No secondary cases occurred in any of the hospitals.  相似文献   
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