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81.
82.
The use of cement emulsified asphalt mortar (CA mortar) in the track structure of high-speed speed railways has been gaining considerations by many researchers due to its coupled merits of the strength of cement as well as the flexibility of asphalt material. The asphalt to cement ratio (A/C) and the compatibility among constituent materials are crucial to the properties of CA mortar. To improve the performance properties and application of CA mortar, it is imperative to have a broad understanding of the composition mechanisms and compatibility between constituent materials. This paper summarizes interesting research outcomes related to the composition and properties of CA mortar. The consumption of water by cement promotes the breakdown of emulsified asphalt, likewise, the adsorption of asphalt droplets on the surface of cement grains retards the hydration process of cement. An appropriate A/C is required for the cement hydration rate to match the speed of demulsification of asphalt emulsion. Depending on the type and properties for which the CA mortar is designed to possess, the A/C ranges from 0.2 to 0.6 for type 1 (CAM I), and 0.6 to 1.2 for type 2 (CAM II). This paper also discusses measures taken to improve performance properties, compatibility, the interaction between constituent materials of CA mortar, and the use of additives as a partial replacement of cement in CA mortar production. The current review also suggests areas of interest for future research studies. This paper is useful to those who aim to understand or study the composition mechanisms and performance properties of CA mortar.  相似文献   
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Eliminating malaria parasites during the asymptomatic but obligate liver stages (LSs) of infection would stop disease and subsequent transmission. Unfortunately, only a single licensed drug that targets all LSs, Primaquine, is available. Targeting host proteins might significantly expand the repertoire of prophylactic drugs against malaria. Here, we demonstrate that both Bcl-2 inhibitors and P53 agonists dramatically reduce LS burden in a mouse malaria model in vitro and in vivo by altering the activity of key hepatocyte factors on which the parasite relies. Bcl-2 inhibitors act primarily by inducing apoptosis in infected hepatocytes, whereas P53 agonists eliminate parasites in an apoptosis-independent fashion. In combination, Bcl-2 inhibitors and P53 agonists act synergistically to delay, and in some cases completely prevent, the onset of blood stage disease. Both families of drugs are highly effective at doses that do not cause substantial hepatocyte cell death in vitro or liver damage in vivo. P53 agonists and Bcl-2 inhibitors were also effective when administered to humanized mice infected with Plasmodium falciparum. Our data demonstrate that host-based prophylaxis could be developed into an effective intervention strategy that eliminates LS parasites before the onset of clinical disease and thus opens a new avenue to prevent malaria.  相似文献   
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BackgroundIn order to institute preventive programmes against harmful traditional oral health practices there is a need to identify targets.ObjectivesTo investigate factors influencing awareness and attendance of traditional oral health practices by residents of a peri-urban community in Ibadan, Nigeria.MethodsA cross-sectional study of adult residents selected by simple random sampling in a peri-urban community in Ibadan, Nigeria, was conducted over a period of six months. Information was obtained with interviewer administered questionnaires. Data were recorded using SPSS version 16 software.ResultsA total of 172 (44.1%) respondents were aware of the existence of traditional healers for dental problems. Only 34 (8.7%) participants had been to traditional healers on account of toothache. About 76.5% reported having relief after treatment with relapse occurring in 12 cases (46.2%). Twenty (58.8%) of these (34) participants said they would not choose this option of treating dental problems in future. Significant associations existed between knowing that traditional healers provided dental treatment and gender (p = 0.001) or history of dental problems (p =0.008).ConclusionThe study showed moderate awareness of traditional oral care practices in Ibadan, Nigeria as influenced by gender and previous dental problems.  相似文献   
85.

Background:

The few studies available in the literature on Wilms’ tumour (WT) from sub-Saharan Africa have reported a dismal outcome for children with the tumour. This study evaluated the risk factors that have been correlated with outcome in the literature and compare these with outcome among our patients.

Materials and Methods:

Cases of histologically confirmed WT between 2009 and 2013 in a tertiary hospital in Northwestern Nigeria were evaluated for gender, age, laterality, symptoms, duration before presentation, stage at presentation, histologic subtype and p53 mutation. These were then correlated with outcome.

Results:

Totally, 30 cases of WT were diagnosed with mean age of 4.8 ± 1.9 years; and male:female ratio of 2:1. No statistically significant relationship with outcome was found for gender (P = 0.138) or histologic subtype (P = 0.671). The most significant variables which positively influenced the outcome were presentation at earlier stages (P = 0.007) and completion of therapy (P = 0.0007). p53 mutation was seen in 3 (16.7%) of 18 cases and was not associated with a poor outcome (P = 0.089). However, 2 of the 3 cases presented in Stage IV and none of them survived the 1st year.

Conclusion:

This study shows that even though p53 mutation was associated with a more aggressive phenotype, the most significant determinants of a good outcome among patients in a developing country like ours is non-blastemal dominant histologic subtype, early stage at presentation and completion of therapy.Key words: Blastema, outcome, p53, Wilms’ tumour  相似文献   
86.
Purpose: To investigate objectively measured physical activity in stroke survivors living in low-income areas of Cape Town, South Africa, specifically to: (a) describe the volume of daily physical activity and time spent in different intensity levels and (b) investigate the association of factors covering the International Classification of Functioning, Disability and Health with sedentary behavior.

Materials and methods: A cross-sectional design was used, where forty-five ambulatory community-dwelling stroke survivors participated. Volume and intensity of physical activity were assessed with accelerometers for three to five consecutive days. Personal and environmental factors, along with body function and activity, were captured. Multiple linear regression was used to investigate factors associated with the percentage of days spent sedentary.

Results: The median number of steps per day was 2393, and of the average 703?minutes of wear time, 80% were spent in sedentary, 15% in light, and 5% in moderate-to-vigorous intensity physical activity. Age, stroke severity, and failing to receive outpatient rehabilitation were independently associated with sedentary, which, taken together, explained 52% of the variance.

Conclusions: Low volumes of physical activity and high amount of sedentary time emphasize the need to develop strategies that will increase physical activity. Providing outpatient rehabilitation in a systematic manner post-stroke is a potential target of health care programs in order to reduce sedentary behavior.
  • Implications for rehabilitation
  • Objectively measured physical activity among community-dwelling survivors of stroke in Cape Town, South Africa was low in volume, and the majority did not meet the recommendations of 150?minutes of at least moderate intensity physical activity.

  • The majority of stroke survivors in South Africa spent most of their time sedentary, which could further increase the risk of cardiovascular impairments.

  • Outpatient rehabilitation should be provided to all patients after stroke since it appears to reduce sedentary time.

  相似文献   
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OBJECTIVES: Autonomic dysfunction is associated with a wide variety of gastrointestinal symptoms. It is unclear how many patients with autonomic dysfunction have slow or rapid gastric emptying. The aim of this study was to determine the prevalence of rapid and delayed solid phase gastric emptying in patients with autonomic dysfunction referred for evaluation of gastrointestinal symptoms and the association of emptying rate with clinical symptoms. METHODS: Retrospective review of all patients with autonomic dysfunction who had a gastric emptying test from January, 1996 to March, 2005. Demographic data, clinical symptoms, composite autonomic scoring scale (CASS) score, and gastric emptying parameters were analyzed. RESULTS: Sixty-one subjects (women 49, age 42 [16-74] yr) with autonomic dysfunction were reviewed. Patients had mild-to-moderate (mean CASS score 3) autonomic dysfunction. Twenty-seven, 17, and 17 patients had rapid, normal, and delayed gastric emptying t(1/2), respectively. In addition, 10 patients had initially rapid emptying in phase 1, with subsequent slowing in phase 2 to produce an overall normal or delayed t(1/2). There was no difference in demographic data or CASS score among the three groups. More patients with initial or overall rapid emptying had diarrhea (70%) compared to patients with normal (33%) or delayed (33%) emptying (P= 0.018). CONCLUSIONS: Unexpectedly, more patients with autonomic dysfunction have rapid rather than delayed gastric emptying. The presence of diarrhea in patients with autonomic symptoms should prompt consideration for the presence of rapid gastric emptying. Conversely, the finding of rapid gastric emptying in patients with gastrointestinal symptoms should prompt consideration for the presence of underlying autonomic dysfunction.  相似文献   
90.
INTRODUCTION: Controversy exists as to whether there is an increased severity or frequency of recurrent hepatitis C viral (HCV) infection in recipients of adult living donor liver transplantation (LDLT) grafts. We sought to examine the time to histological recurrence and survival in HCV (+) patients who underwent split liver transplantation (SLT), which is technically similar to what occurs in the LDLT procedure. METHODS: Twenty four HCV (+) adult recipients were identified through the UNOS database as having had SLT procedures at three centers: Mount Sinai Medical Center, University of Chicago, and University of California at Los Angeles. Of these, 17 patients with comprehensive data were matched to 32 HCV (+) patients who underwent whole deceased donor liver transplantation (DDLT) during the same time period. Outcome and time to initial HCV recurrence as documented by liver biopsy were assessed. Liver biopsy was performed when clinically indicated. RESULTS: Patients who had SLT were significantly older (P=.01). There was no difference in number of rejection episodes (P=.40). Fifteen of 17 SLT (88%) versus 24/32 DDLT (75%) patients had documented HCV recurrence by biopsy (P=.46). The time to median cumulative incidence of recurrence of HCV post-liver transplantation was 12.6 months (SLT) versus 39.8 months (DDLT) patients. There was no difference in survival between SLT and DDLT patients (47 vs 70 months, P=.62) nor in cumulative incidence of histological HCV recurrence at 1, 2, and 3 years (P=.198, .919, and .806, respectively). CONCLUSION: There is no difference in the cumulative incidence of histological recurrence of HCV post-liver transplant or in survival between recipients of deceased donor and split liver transplants.  相似文献   
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