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排序方式: 共有686条查询结果,搜索用时 15 毫秒
621.
Liu Q Liu R Kashyap MV Agarwal R Shi X Wang CC Yang SH 《中国神经肿瘤杂志》2009,7(3):203-203
OBJECT: Brainstem gliomas are common in children and have the worst prognosis of any brain tumor in this age group. On the other hand, brainstem gliomas are rare in adults, and the authors of some clinical studies have suggested that this lesion behaves dif ferently in adults than in children. In the present study, the authors test an orthotopic C6 brainstem glioma model in juvenile and adult rats, and investigate the biological behavior of this lesion in the 2 age groups. METHODS: The C6 glioma cells were stereotacti eally implanted into the pons of juvenile or adult male rats. Neurological presentation and survival time were recorded. 相似文献
622.
623.
CC Bonifácio§ CJ Kleverlaan† DP Raggio‡ A Werner† RCR de Carvalho WE van Amerongen§ 《Australian dental journal》2009,54(3):233-237
Background: This study evaluated mechanical properties of glass ionomer cements (GICs) used for atraumatic restorative treatment. Wear resistance, Knoop hardness (Kh), flexural (Fs ) and compressive strength (Cs ) were evaluated. The GICs used were Riva Self Cure (RVA), Fuji IX (FIX), Hi Dense (HD), Vitro Molar (VM), Maxxion R (MXR) and Ketac Molar Easymix (KME).
Methods: Wear was evaluated after 1, 4, 63 and 365 days. Two-way ANOVA and Tukey post hoc tests (P = 0.05) analysed differences in wear of the GICs and the time effect. Fs , Cs , and Kh were analysed with one-way ANOVA.
Results: The type of cement (p < 0.001) and the time (p < 0.001) had a significant effect on wear. In early-term wear and Kh, KME and FIX presented the best performance. In long-term wear, F s and Cs , KME, FIX and HD had the best performance. Strong explanatory power between Fs and the Kh (r2 = 0.85), Cs and the Kh (r2 = 0.82), long-term wear and Fs of 24 h (r2 = 0.79) were observed.
Conclusions: The data suggested that KME and FIX presented the best in vitro performance. HD showed good results except for early-term wear. 相似文献
Methods: Wear was evaluated after 1, 4, 63 and 365 days. Two-way ANOVA and Tukey post hoc tests (P = 0.05) analysed differences in wear of the GICs and the time effect. F
Results: The type of cement (p < 0.001) and the time (p < 0.001) had a significant effect on wear. In early-term wear and Kh, KME and FIX presented the best performance. In long-term wear, F
Conclusions: The data suggested that KME and FIX presented the best in vitro performance. HD showed good results except for early-term wear. 相似文献
624.
MA Braga O Tarzia CC Bergamaschi FA Santos ED Andrade FC Groppo 《International journal of dental hygiene》2009,7(2):126-130
Abstract: Objective: The aim of the present study was to compare the effect of low‐dose pilocarpine and cevimeline as stimulants for salivary flow in healthy subjects. Methods: In this cross‐over clinical trial with a 1‐week washout period, 40 male volunteers were submitted to an oral dose of pilocarpine 1% (Salagen?) ?60 μg kg?1 body‐weight (Group 1) or Cevimeline (Evoxac?) ?30 mg (Group 2). Saliva samples were collected and the salivary flow rate was measured (ml min?1) at baseline and 20, 40, 60, 80, 140 and 200 min after administration of drugs. In addition, salivary secretion was also measured under mechanical stimulation to observe salivary gland function. Results: The data were analyzed by Friedman and Wilcoxon signed‐rank tests (significance level = 5%). Pilocarpine and cevimeline significantly increased salivary flow 140 min after intake. There was a significant higher secretion with cevimeline 140 and 200 min after administration. There were no differences seen among subjects in the salivary glands function by mechanical stimulation. Conclusion: Both drugs showed efficacy in increasing the salivary flow in healthy volunteers, but cevimeline was more effective than pilocarpine. 相似文献
625.
The authors have developed an automated algorithm for segmentation of magnetic resonance images (MRI) of the human brain. They investigated the quantitative analysis of tissue-specific human motor response through an approach combining gradient echo functional MRI and automated segmentation analysis. Fifteen healthy volunteers, placed in a 1.5 T clinical MR imager, performed a self-paced finger opposition throughout the activation periods. T1-weighted images (WI), T2WI, and proton density WI were acquired for segmentation analysis. Single-slice axial T2* fast low-angle shot (FLASH) images were obtained during the functional study. Pixelwise cross-correlation analysis was performed to obtain an activation map. A cascaded algorithm, combining Kohonen feature maps and fuzzy C means, was applied for segmentation. After processing, masks for gray matter, white matter, small vessels, and large vessels were generated. Tissue-specific analysis showed a signal change rate of 4.53% in gray matter, 2.98% in white matter, 5.79% in small vessels, and 7.24% in large vessels. Different temporal patterns as well as different levels of activation were identified in the functional response from various types of tissue. High correlation exists between cortical gray matter and subcortical white matter (r = 0.957), while the vessel behaves somewhat different temporally. The cortical gray matter fits best to the assumed input function (r = 0.957) followed by subcortical white matter (r = 0.829) and vessels (r = 0.726). The automated algorithm of tissue-specific analysis thus can assist functional MRI studies with different modalities of response in different brain regions. 相似文献
626.
627.
Accuracy and feasibility of point-of-care and continuous blood glucose analysis in critically ill ICU patients 总被引:1,自引:0,他引:1
Corstjens AM Ligtenberg JJ van der Horst IC Spanjersberg R Lind JS Tulleken JE Meertens JH Zijlstra JG 《Critical care (London, England)》2006,10(5):R135-7
Introduction
To obtain strict glucose regulation, an accurate and feasible bedside glucometry method is essential. We evaluated three different types of point-of-care glucometry in seriously ill intensive care unit (ICU) patients. The study was performed as a single-centre, prospective, observational study in a 12-bed medical ICU of a university hospital. 相似文献628.
de Jonge Hendrik CC Azad Kishwar Seward Nadine Kuddus Abdul Shaha Sanjit Beard James Costello Anthony Houweling Tanja AJ Fottrell Ed 《BMC pregnancy and childbirth》2014,14(1):1-7
Ethiopia is among seven high-mortality countries which have achieved the fourth millennium development goal with over two-thirds reduction in under-five mortality rate. However, the proportion of neonatal deaths continues to rise and recent studies reported low coverage of the essential interventions saving newborn lives. In the context of low uptake of health facility delivery, it is relevant to explore routine practices during home deliveries and, in this study, we explored the sequence of immediate newborn care practices and associated beliefs following home deliveries in rural communities in Ethiopia. Between April-May 2013, we conducted 26 semi-structured interviews and 2 focus group discussions with eligible mothers, as well as a key informant interview with a local expert in traditional newborn care practices in rural Basona woreda (district) near the urban town of Debrebirhan, 120 km from Addis Ababa, Ethiopia. The most frequently cited sequence of newborn care practices reported by mothers with home deliveries in the rural Basona woreda was to tie the cord, immediately bath then dry the newborn, practice ‘Lanka mansat’ (local traditional practice on newborns), give pre-lacteal feeding and then initiate breastfeeding. For ‘Lanka mansat’, the traditional birth attendant applies mild pressure inside the baby’s mouth on the soft palate using her index finger. This is performed believing that the baby will have ‘better voice’ and ‘speak clearly’ later in life. Coverage figures fail to tell the whole story as to why some essential interventions are not practiced and, in this study, we identified established norms or routines within the rural communities that determine the sequence of newborn care practices following home births. This might explain why some mothers delay initiation of breastfeeding and implementation of other recommended essential interventions saving newborn lives. An in-depth understanding of established routines is necessary, and community health extension workers require further training and negotiation skills in order to change the behaviour of mothers in practicing essential interventions while respecting local values and norms within the communities. 相似文献
629.
Barton KN Stricker H Kolozsvary A Kohl R Heisey G Nagaraja TN Zhu G Lu M Kim JH Freytag SO Brown SL 《The Journal of urology》2006,175(5):1921-1925
PURPOSE: A significant limitation of adenoviral mediated suicide gene therapy is poor gene distribution in vivo. The choice of vehicle has been demonstrated to affect the level of adenoviral delivered gene transduction. We examined the hypotheses that 1) adenovirus suspended in PEG400 improves gene expression in the na?ve canine prostate model, 2) improved transgene expression with PEG400 results in improved tumor control and 3) vehicle affects the initial adenoviral spread from a single intratumor injection. MATERIALS AND METHODS: The magnitude and volume of gene expression were measured 24 hours following intraprostatic injection of adenovirus suspended in PEG400 (12.5% weight per volume) or saline as vehicle. Tumor growth delay was measured in mice bearing human tumor xenografts following the injection of adenovirus in PEG400 and saline. The initial spread of adenovirus was measured by confocal microscopy following a single injection of fluorescently labeled adenoviral particles in human tumor xenografts using each vehicle. RESULTS: Adenovirus suspended in PEG400 provided an average of twice the level of gene expression in the canine prostate and significantly better tumor control relative to saline in preclinical tumor models (p = 0.046 and 0.036, respectively). The initial spread of adenovirus with PEG400 was superior to that of adenovirus in saline and the latter was largely limited to the needle tract. CONCLUSIONS: Adenoviral gene therapy vectors suspended in PEG400 results in improved tumor control because of greater initial adenoviral spread, and the increased volume and magnitude of gene expression in vivo. 相似文献
630.