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61.
A highly efficient and straightforward synthesis of N-fused heterocyclic compounds including N′-(1-(4-nitrophenyl)ethylidene)imidazo[1,2-a]pyridine-6-carbohydrazide and N′-(1-(4-nitrophenyl)ethylidene)pyrido[1,2-a]pyrimidine-7-carbohydrazide derivatives is successfully achieved via a five-component cascade reaction utilizing cyanoacetohydrazide, 4-nitroacetophenone, 1,1-bis(methylthio)-2-nitroethylene and various diamines in a mixture of water and ethanol. The new efficient domino protocol involving a sequence of N,N-acetal formation, Knoevenagel condensation, Michael reaction, imine–enamine tautomerization and N-cyclization as key steps. The merit of this catalyst free approach is highlighted by its easily available starting materials, operational simplicity, clean reaction profile, the use of environmentally benign solvents and tolerance of a wide variety of functional groups.An easy synthesis of novel and highly substituted imidazo[1,2-a]pyridines and pyrido[1,2-a]pyrimidines using heterocyclic ketene aminals. 相似文献
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Sara A. Alfadda Hayam A. Al-Fallaj Hajar A. Al-Banyan Ruba M. Al-Kadhi 《Saudi Dental Journal》2015,27(2):93-98
Objective
The purpose of this study was to determine whether there is a correlation between the clinical quality of conventional complete dentures and patient quality of life.Materials and methods
This study included a random sample of 32 completely edentulous patients (15 males and 17 females) who were treated with conventional complete dentures. Using a validated questionnaire, three investigators evaluated the dentures independently on the basis of seven clinical parameters: esthetics (lip support and lower lip line), retention and stability of the maxillary and the mandibular dentures, and occlusion. Patients completed the validated Oral Health Impact Profile-20 (OHIP-20) questionnaire. Correlations were determined by using the point-biserial correlation coefficient.Results
Clinicians rated the overall clinical quality of the dentures satisfactory in 80.3% of patients. The mean (±standard deviation) total OHIP-20 score was 56.3 ± 15.9 out of a possible 120 maximum. A statistically significant negative correlation was found between the stability of the maxillary and mandibular dentures and the total OHIP-20 score (p = 0.009 and 0.0023, respectively). A negative correlation between the total OHIP-20 score and the retention of the mandibular denture approached significance (p = 0.092). Esthetics, retention of the maxillary denture, and occlusion were not correlated with patient quality of life (p > 0.169).Conclusion
Stability of the maxillary and mandibular dentures is the denture quality parameter that can most significantly affect patient quality of life. 相似文献64.
Amir Ahmadi Nader Maroufi Hamid Behtash Hajar Zekavat Mohamad Parnianpour 《European spine journal》2009,18(11):1677-1685
The study design is a prospective, case–control. The aim of this study was to develop a reliable measurement technique for
the assessment of lumbar spine kinematics using digital video fluoroscopy in a group of patients with low back pain (LBP)
and a control group. Lumbar segmental instability (LSI) is one subgroup of nonspecific LBP the diagnosis of which has not
been clarified. The diagnosis of LSI has traditionally relied on the use of lateral functional (flexion–extension) radiographs
but use of this method has proven unsatisfactory. Fifteen patients with chronic low back pain suspected to have LSI and 15
matched healthy subjects were recruited. Pulsed digital videofluoroscopy was used to investigate kinematics of lumbar motion
segments during flexion and extension movements in vivo. Intersegmental linear translation and angular displacement, and pathway
of instantaneous center of rotation (PICR) were calculated for each lumbar motion segment. Movement pattern of lumbar spine
between two groups and during the full sagittal plane range of motion were analyzed using ANOVA with repeated measures design.
Intersegmental linear translation was significantly higher in patients during both flexion and extension movements at L5–S1
segment (p < 0.05). Arc length of PICR was significantly higher in patients for L1–L2 and L5–S1 motion segments during extension movement
(p < 0.05). This study determined some kinematic differences between two groups during the full range of lumbar spine. Devices,
such as digital videofluoroscopy can assist in identifying better criteria for diagnosis of LSI in otherwise nonspecific low
back pain patients in hope of providing more specific treatment. 相似文献
65.
Vitamin D insufficiency among postmenopausal women in urban and rural areas in Guilan, Northern Iran
This study aimed to describe vitamin D status in postmenopausal women in urban and rural areas in Guilan, northern Iran. Between October 2004 and February 2005 a group of 750 women older than 50 years was randomly selected from urban and rural areas in Guilan. The participants were interviewed to collect data on age, educational level, body weight, height, employment status, reproductive history, medications, history of illness, and supplement use. Serum 25(OH) D was measured in 646 women (427 in urban areas and 219 women in rural areas). Serum 25(OH) D levels in urban and rural postmenopausal women were 18.5 ± 13.5 ng/ml and 22.9 ± 13.8 ng/ml (P < 0.0001), respectively. In urban and rural areas, 84.7% and 79.5% of the women had serum 25(OH) D levels less than 30 ng/ml, respectively. In this study, serum vitamin D levels and prevalence of vitamin D insufficiency was related to educational level in urban women. The urban women in the lowest educational level (<5 years schooling) had a better vitamin D status than other educational groups. This study showed that a high proportion of postmenopausal women living in Guilan province had vitamin D insufficiency. Vitamin D inadequacy was more common in urban areas and especially in the upper social class. Supplement use and national strategies to prevent vitamin D insufficiency are strongly needed in this community. 相似文献
66.
Contrast-enhanced 64-section coronary multidetector CT angiography versus conventional coronary angiography for stent assessment 总被引:5,自引:0,他引:5
Das KM El-Menyar AA Salam AM Singh R Dabdoob WA Albinali HA Al Suwaidi J 《Radiology》2007,245(2):424-432
PURPOSE: To prospectively evaluate the accuracy of 64-section computed tomography (CT) for diagnosis of stent restenosis, by using conventional coronary angiography as the reference standard. MATERIALS AND METHODS: The ethics committee granted permission for the study; patients gave written consent. Contrast material-enhanced coronary CT angiography was performed in 53 patients (45 men, eight women; mean age, 54 years +/- 9 [standard deviation]) suspected of having stent restenosis. Coronary CT angiographic findings were compared with conventional coronary angiographic findings. Two physicians analyzed coronary CT angiographic data sets with multiplanar reformatted images and three-dimensional reformations by using a volume-rendering technique and looked for stent detectability, low-attenuation in-stent filling defects, and grades of restenosis. Conventional coronary angiographic results were interpreted by one of several observers in consensus for stent restenosis; they were blinded to coronary CT angiographic data. Statistical software and general estimating equations were used for data analysis. RESULTS: One hundred ten stents were identified in 53 patients. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of coronary CT angiography in detection of in-stent restenosis were 96.9%, 88.0%, 77.5%, 98.5%, and 91%, respectively. Coronary CT angiography depicted in-stent low-attenuation filling defects with an accuracy of 91% and negative predictive value of 98.5% (95% confidence interval: 90.9, 99.9). Coronary CT angiography depicted the status of 97 of 107 stents. There was no significant difference between in-stent lumen visibility and stent diameter (P = .104). Coronary CT angiography helped diagnose 15 of 18 stent restenoses with less than 50% narrowing, five of five stent restenoses with 50%-74% narrowing, and nine of nine (100%) stent restenoses with 75% or greater narrowing or total occlusion of the stent lumen. CONCLUSION: Coronary CT angiography can depict in-stent low-attenuation filling defects, which appear to be a reliable sign of stent restenosis, and 64-section CT depicts such defects with a high degree of accuracy. 相似文献
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69.
Hajar Motamed Homayoon Bashiri Farideh Yari Arezo Bozorgomid Mosayeb Rostamian Yosef Azarakhsh Azam Hosseini Roya Chegene lorestani 《急性病杂志》2021,10(1):23-27
Objective: To examine whether the platelet index would be applicable for the diagnosis of community-acquired pneumonia (CAP).Methods: In this study, 64 CAP patients (the case group) and 68 healthy children (the control group) were included from 2017 to 2018. Baseline variables were recorded including total white blood cells, neutrophils, lymphocytes, red blood cells, platelet, mean platelet volume, platelet distribution width, erythrocyte sedimentation rate, and C-reactive protein, and compared between the case group and the control group. The cutoff value, sensitivity, and specificity of neutrophil-to-lymphocyte ratio, platelet, neutrophils, lymphocytes, and platelet larger cell ratio were calculated by receiver-operating characteristic curves. Results: The median platelet count of the case group and the control group were (411.09±67.40) mm3 and (334.48±78.15) mm3, respectively (P=0.000). The median neutrophil count of the case group was higher than that of the control group, while the lymphocyte level of the case group was lower. Differences in other variables including the mean platelet volume, platelet distribution width, C-reactive protein, and erythrocyte sedimentation rate were not statistically significant between the two groups. Conclusions: Due to the different levels of platelet, neutrophil and lymphocyte indices in the case and the control group, these indices can be used simultaneously for the diagnosis of CAP. 相似文献
70.
Seyed Saeed Hashemi Nazari Kamyar Mansori Hajar Nazari Kangavari Ahmad Shojaei Shahram Arsang-Jang 《Yebang Ŭihakhoe chi》2022,55(2):164
ObjectivesWe aimed to estimate the space-time distribution of the risk of suicide mortality in Iran from 2006 to 2016.MethodsIn this repeated cross-sectional study, the age-standardized risk of suicide mortality from 2006 to 2016 was determined. To estimate the cumulative and temporal risk, the Besag, York, and Mollié and Bernardinelli models were used.ResultsThe relative risk of suicide mortality was greater than 1 in 43.0% of Iran’s provinces (posterior probability >0.8; range, 0.46 to 3.93). The spatio-temporal model indicated a high risk of suicide in 36.7% of Iran’s provinces. In addition, significant upward temporal trends in suicide risk were observed in the provinces of Tehran, Fars, Kermanshah, and Gilan. A significantly decreasing pattern of risk was observed for men (β, −0.013; 95% credible interval [CrI], −0.010 to −0.007), and a stable pattern of risk was observed for women (β, −0.001; 95% CrI, −0.010 to 0.007). A decreasing pattern of suicide risk was observed for those aged 15–29 years (β, −0.006; 95% CrI, −0.010 to −0.0001) and 30–49 years (β, −0.001; 95% CrI, −0.018 to −0.002). The risk was stable for those aged >50 years.ConclusionsThe highest risk of suicide mortality was observed in Iran’s northwestern provinces and among Kurdish women. Although a low risk of suicide mortality was observed in the provinces of Tehran, Fars, and Gilan, the risk in these provinces is increasing rapidly compared to other regions. 相似文献