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81.
82.
Use of a run-in period to decrease loss to follow-up in the Contact Lens and Myopia Progression (CLAMP) study 总被引:1,自引:0,他引:1
Rigid gas permeable (RGP) contact lenses are initially less comfortable to wear than spectacles. In previous studies evaluating the use of RGP contact lenses to control myopia, more subjects randomly assigned to wear RGP contact lenses have been lost to follow-up than spectacle wearers. Previous rigid contact lens myopia control studies have lost 44% and 47% of the rigid contact lens wearers. This unequal loss to follow-up may compromise the results of the study, so we conducted a run-in period prior to randomized treatment-group assignment to ensure that all participants could adapt to RGP contact lens wear. We enrolled 147 children ages 8-11 years with myopia in the run-in period. Of the 147 subjects, 116 (78.9%) were able to wear RGP contact lenses for at least 40 hours per week and reported that they were "usually comfortable" or "always comfortable." After 3 years, no subjects were lost to follow-up. The run-in period greatly reduced the loss to follow-up suffered by previous RGP contact lens myopia progression studies and may help provide more definitive answers regarding myopia control with RGP contact lenses. 相似文献
83.
Tomic K Mladinov D Batelja-Vuletic L Spajic B Mijic A Tomas D Belicza M Kruslin B 《Pathology, research and practice》2007,203(9):647-652
The aim of this study was to analyze morphometric parameters of renal arteries (longest diameter and tunica media thickness) in patients with renal cell carcinoma (RCC), to look into their relationship to tumor necrosis and to compare them with morphometric parameters recorded in a control group. We analyzed archival cases of RCC diagnosed in 2003 that also contained routinely sampled specimens of distal segments of renal artery. The control group consisted of specimens from both renal arteries obtained from 16 patients at routine autopsy during 2004-2005. Autopsy, as well as further histological analysis, did not disclose any malignant disease in the control group. Morphometric analysis of diameter and thickness of the renal artery tunica media was performed using Issa 3.1 software (Vamstek 2002, Zagreb, Croatia). The comparison of tunica media thickness showed that renal arteries from RCC cases were significantly thicker compared to distal parts of renal arteries in the control group (p=0.0002). Although renal artery samples from cases with necrotic tumor areas were thicker than those without tumor necrosis, the difference was not statistically significant. It is concluded that significantly thicker tunica media characterizes renal arteries in the group of patients with RCC when compared with the control group. 相似文献
84.
Kerlikowske K 《The New England journal of medicine》2007,356(3):297-300
85.
Twardella Dorothee Geiss Karla Radespiel-Tröger Martin Benner Axel Ficker Joachim H. Meyer Martin 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2018,61(1):20-31
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Beim Lungenkrebs werden verschiedene histologische Subtypen unterschieden. Im Wesentlichen sind dies das kleinzellige Karzinom,... 相似文献
86.
Modeling clustering and treatment effect heterogeneity in parallel and stepped‐wedge cluster randomized trials
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Cluster randomized trials are frequently used in health service evaluation. It is common practice to use an analysis model with a random effect to allow for clustering at the analysis stage. In designs where clusters are exposed to both control and treatment conditions, it may be of interest to examine treatment effect heterogeneity across clusters. In designs where clusters are not exposed to both control and treatment conditions, it can also be of interest to allow heterogeneity in the degree of clustering between arms. These two types of heterogeneity are related. It has been proposed in both parallel cluster trials, stepped‐wedge, and other cross‐over designs that this heterogeneity can be allowed for by incorporating additional random effect(s) into the model. Here, we show that the choice of model parameterization needs careful consideration as some parameterizations for additional heterogeneity induce unnecessary or implausible assumptions. We suggest more appropriate parameterizations, discuss their relative advantages, and demonstrate the implications of these model choices using a real example of a parallel cluster trial and a simulated stepped‐wedge trial. 相似文献
87.
Luis Cardoso Rasquin Fabíola Bastos de Carvalho Regina Karla de Pontes Lima 《Journal of applied oral science : revista FOB》2007,15(1):65-69
Objective:
The aim of this study was to evaluate the biomechanical preparation of flattened root canals using the following systems: Endo-Eze AET stainless steel oscillatory instruments (Ultradent) and RaCe rotary NiTi instruments (FKG Dentaire).Materials and Methods:
Twenty extracted human mandibular incisors were randomly assigned to two groups: Group 1 - Instrumentation with oscillatory Endo-Eze AET files (oscillatory technique); Group 2 - Instrumentation with rotary NiTi RaCe files (rotary technique). The teeth were decoronated, had their apices and coronal openingssealed with sticky wax and were embedded in crystal-clear orthophtalic polyester resin. The roots were sectioned transversally with diamond discs at 10 mm (middle third) and 5 mm (apical third) from the apex and the segments were reassembled for instrumentation. The sections were photographed before and after root canal instrumentation and evaluated with respect to whether the original root canal shape was modified by instrumentation. To evaluate the differences in the root canal shape before and after biomechanical preparation, scores were given regarding the instruments touch on the intracanal walls.Results:
In middle third of the root canals instrumented with the rotary system, there was a change in the original canal anatomy (p<0.05), with formation of a protuberance in the mesiodistal direction. This protuberance did not occur when the oscillatory instrumentation was used. The oscillatory system had better results in the middle and apical thirds as evaluated by Dunn’s multiple-comparison test (p>0.05).Conclusion:
Under the tested conditions, Endo-Eze oscillatory system yielded the instrumentation of all flattened root canal walls, maintaining the canal original shape throughout the biomechanical preparation, and was more effective than RaCe rotary system. 相似文献88.
Segundo AS Hennemann K Fontanella VR Rösing C 《Journal of the International Academy of Periodontology》2007,9(1):26-31
The aim of the present study was to determine the role of chronic stress in the pathogenesis of ligature-induced periodontal disease in rats. Fifty-three Wistar rats were randomly assigned to 4 experimental groups: 1--ligature; 2--ligature + stress; 3--stress only; 4--control. After 30 days the animals were sacrificed, blood samples were collected and histological sections were made for histometric analysis. The stress parameters evaluated were weight of thymus, spleen, adrenal glands and plasma glucocorticoid levels. Analysis of adrenal glands showed statistically significant differences between stressed and non-stressed groups (one-way ANOVA, p < 0.05). Plasma glucocorticoid levels were higher in Group 3 and lower in Group 2 (81.1 nmol/I versus 62.5 nmol/l, p < 0.05). Histometric measurements from the bone crest and from the first attached fiber were taken for all groups and for Groups 1 and 2 for the sites with and without ligatures. The ligature sites always displayed higher mean values than non-ligated sites (paired sample t test, p < 0.05). No statistically significant differences were observed between Groups 1 and 2 with regard to the ligated sites. However, differences were observed between Groups 1 and 2 in histometric bone levels in the non-ligated sites (mean values of 0.81 and 0.55 mm, respectively, p < 0.05). It may be concluded that stress can have a possible role in the activation of the hypothalamus-pituitary-adrenal (HPA) axis, with different levels of glucocorticoid release. 相似文献
89.
Roxanne Charles Asoke Basu Bryan Sanford Auria King‐Cenac Sharmine Melville‐Edwin Patricia Pow‐Brown Candice Sant Karla Georges 《Transboundary and Emerging Diseases》2020,67(Z2):129-134
Ticks and the pathogens they transmit can cause high morbidity and mortality in domestic animals. As part of a larger study to determine the tick‐borne pathogens infesting domestic animals and wildlife, the aim of this study was to survey the tick species infesting the canine and cattle populations in Trinidad, Tobago and St. Lucia. A total of 1,990 ticks were collected off 179 dogs in Trinidad (n = 163) and Tobago (n = 16) between June 2016 and 2018. Ticks were also collected from cattle throughout Trinidad (n = 1,098), Tobago (n = 306) and St. Lucia (n = 176). Collected ticks were morphologically identified using standard taxonomic keys. Tick‐infested dogs were characterized as pets (n = 161) or hunting dogs (n = 18). Only two tick species, Rhipicephalus sanguineus (1,926; 96.8%) and Amblyomma ovale (64; 3.2%), were found on the dogs. A total of 169 (94.4%) dogs and 10 (5.6%) dogs were infested with R. sanguineus and A. ovale, respectively. Three dogs (1.7%) were infested with both tick species. Hunting dogs or those closely associated with them were infested with A. ovale. Rhipicephalus sanguineus was widely distributed throughout both islands, whereas A. ovale was restricted to small foci in three rural settlements in both Trinidad (n = 2) and Tobago (n = 1). Rhipicephalus (Boophilus) microplus (n = 1,404) was the only tick species found in cattle from Trinidad (n = 62) and Tobago (n = 20), whilst R. B. microplus (n = 171) and Amblyomma variegatum (n = 5) were found infesting 14 and two heads of cattle, respectively, in St. Lucia. These preliminary findings will aid in determining whether there are links between ticks and tick‐borne pathogens associated with domestic, wildlife species and humans and give further insight into the potential movement of ticks and their pathogens between the human, animal and tropical forest interface. 相似文献
90.
Camargo Bárbara Tideman Sartorio Coca Kelly Pereira Amir Lisa Helen Corrêa Luciana Aranha Ana Cecília Corrêa Marcacine Karla Oliveira Abuchaim Érika de Sá Vieira Abrão Ana Cristina Freitas de Vilhena 《Lasers in medical science》2020,35(1):63-69
Lasers in Medical Science - Photobiomodulation with low-level laser therapy (PBM-LLLT) has been introduced as a new tool to relieve nipple pain and repair nipple damage in breastfeeding women;... 相似文献