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排序方式: 共有2749条查询结果,搜索用时 15 毫秒
71.
Maha Ibrahim Metwally Mohammad Abd Alkhalik Basha Ghada Adel AbdelHamid Mohamad Gamal Nada Reham Ramadan Ali Reem Abdel Fattah frere Al Shaimaa Fathi Elshetry 《The British journal of radiology》2021,94(1120)
Objectives:To set age-specific normal reference values for brainstem, cerebellar vermis, and peduncles measurements and characterize values’ variations according to gender, age, and age by gender interaction.Methods:565 normal brain magnetic resonance examinations with normal anatomy and signal intensity of the supra- and infratentorial structures were categorized into six age groups (infant, child, adolescent, young adult, middle-age adult, and old aged adults). Patients with congenital malformations, gross pathology of the supra- or infratentorial brain, brain volume loss, developmental delay, metabolic disorders, and neuropsychological disorders (n = 2.839) were excluded. On midsagittal T1 weighted and axial T2 weighted images specific linear diameters and ratios of the brainstem, cerebellar vermis, and peduncles were attained. Two observers assessed a random sample of 100 subjects to evaluate the inter- and intraobserver reproducibility. Intraclass correlation coefficients, means ± standard deviation, one and two-way analysis of variance tests were used in the statistical analysis.Results:Good to excellent inter- and intraobserver measurements’ reproducibility were observed, except for the transverse diameter of the midbrain, the anteroposterior diameter of the medulla oblongata at the pontomedullary and cervicomedullary junctions, cerebellar vermis anteroposterior diameter, and thickness of the superior cerebellar peduncle. Age-specific mean values of the investigated measurements were established. A significant gender-related variation was recorded in the anteroposterior diameter of the basis pontis (p = 0.044), the anteroposterior diameter of the medulla oblongata at the cervicomedullary junction (p = 0.044), and cerebellar vermis height (p = 0.018). A significant age-related change was detected in all measurements except the tectal ratio. Age by gender interaction had a statistically significant effect on the tectal ratio, inferior, and middle cerebellar peduncles’ thickness (p = 0.001, 0.022, and 0.028, respectively).Conclusion:This study provides age-specific normal mean values for various linear dimensions and ratios of the posterior fossa structures with documentation of measurements’ variability according to gender, age, and their interaction.Advances in knowledge:It provides a valuable reference in the clinical practice for easier differentiation between physiological and pathological conditions of the posterior fossa structures especially various neurodegenerative diseases and congenital anomalies. 相似文献
72.
This study addresses the clinical problem of the patient with breast cancer that has been operated on for an ovarian mass. It specifies the spectrum of histopathologic diagnoses and the differentiating magnetic resonance imaging (MRI) features of ovarian masses with correlations between clinical features, histopathologic, and MRI findings. Sensitivity and specificity of MRI vs histopathology in diagnosing malignancy are estimated. The study included 53 women with breast cancer who underwent surgery for an ovarian mass. Complete medical records, US and MRI images for the ovarian mass, and histopathology slides of both breast and ovarian resection specimens were reviewed and analyzed retrospectively. Thirty-six (67.9 %) patients had benign masses, and 17 (32.1%) had malignant masses, of which 8 (15.1%) were primary ovarian malignancies and 9 (17%) were metastatic from breast carcinomas. There was a significant association between benign and primary malignant ovarian masses and stage II breast cancer (P = .00). There was a significant association between metastatic ovarian masses and stage III to IV breast disease (P = .00) and negative estrogen receptor status (P = .05). Magnetic resonance imaging had a specificity of 91.7% and a sensitivity of 94.1% in diagnosing malignant ovarian masses. In conclusion, the spectrum of ovarian masses diagnosed in patients with breast cancer is broad, including benign lesions, primary ovarian malignancies, and breast metastases. Knowledge of the imaging features may allow a specific diagnosis aiding in surgical planning. Despite the high specificity and sensitivity of MRI to differentiate benign from malignant lesions, the unique ability to differentiate between primary and metastatic malignancies is conserved to histopathology. 相似文献
73.
Badr E. S. El‐Bialy Mabrouk A. Abd Eldaim Azza Hassan Mohamed M. Abdel‐Daim 《Environmental toxicology》2020,35(2):124-135
This study was carried out to evaluate the protective effects of Panax ginseng aqueous extract (GAE) against hepatorenal toxicity induced by lambda‐cyhalothrin‐acetamiprid insecticide mixture in rats. A total of 32 male albino rats were assigned into four groups. Normal control group received distilled water. Insecticide control group intoxicated with the insecticide at a dose of 2.14 mg/kg b.wt orally day after day for 45 days. GAE control group was treated with GAE at a dose 200 mg/kg b.wt orally. GAE experimental group was administered GAE 1 hour before insecticide administration. Intoxication of rats with the insecticide caused a significant increase in serum aspartate aminotransferase and alanine aminotransferase activities and urea and creatinine levels as well as malondialdehyde concentration and proteins expression of caspase‐3 and induced nitric oxide synthase in hepatic and renal tissues. However, it decreased the serum levels of total protein and globulin and reduced the glutathione content and catalase activity in hepatic and renal tissues. In addition, insecticide induced histopathological alterations in both hepatic and renal tissues. In contrast, GAE modulated insecticide‐induced alterations in liver and kidney functions and structures as it ameliorated the effects of insecticide on the above mentioned parameters. These results indicated that GAE was a potent antioxidant agent that could protect rats against insecticide‐induced hepatorenal toxicity. 相似文献
74.
75.
Psychometric properties of the revised Malay version Medical Outcome Study Social Support Survey using confirmatory factor analysis among postpartum mothers
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76.
Hamady Dieng Rahimah Binti Hassan Ahmad Abu Hassan Idris Abd Ghani Fatimah Bt Abang Tomomitsu Satho Fumio Miake Hamdan Ahmad Yuki Fukumitsu Nur Aida Hashim Wan Fatma Zuharah Nur Faeza Abu Kassim Abdul Hafiz Ab Majid Rekha Selvarajoo Cirilo Nolasco-Hipolito Olaide Olawunmi Ajibola Andrew Alek Tuen 《Acta tropica》2015
Even with continuous vector control, dengue is still a growing threat to public health in Southeast Asia. Main causes comprise difficulties in identifying productive breeding sites and inappropriate targeted chemical interventions. In this region, rural families keep live birds in backyards and dengue mosquitoes have been reported in containers in the cages. To focus on this particular breeding site, we examined the capacity of bird fecal matter (BFM) from the spotted dove, to support Aedes albopictus larval growth. The impact of BFM larval uptake on some adult fitness traits influencing vectorial capacity was also investigated. In serial bioassays involving a high and low larval density (HD and LD), BFM and larval standard food (LSF) affected differently larval development. At HD, development was longer in the BFM environment. There were no appreciable mortality differences between the two treatments, which resulted in similar pupation and adult emergence successes. BFM treatment produced a better gender balance. There were comparable levels of blood uptake and egg production in BFM and LSF females at LD; that was not the case for the HD one, which resulted in bigger adults. BFM and LSF females displayed equivalent lifespans; in males, this parameter was shorter in those derived from the BFM/LD treatment. Taken together these results suggest that bird defecations successfully support the development of Ae. albopictus. Due to their cryptic aspects, containers used to supply water to encaged birds may not have been targeted by chemical interventions. 相似文献
77.
78.
Background
Obesity in type 2 diabetes patients is a serious health issue by itself; it is also associated with other health problems including psychiatric illnesses. The psychological effects of dieting and weight loss have been a matter of controversy in the field of obesity management.Objective
The aim of this study was to compare the impact of weight loss because of aerobic exercise training and dietary measures on psychological wellbeing and biochemical modulation in obese type 2 diabetes patients.Material and methods
One hundred obese type 2 diabetes patients of both sexes participated in this study, and were included into two equal groups. The first group (A) received aerobic exercise training, three sessions per week for three months combined with dietary measures. The second group (B) received no training intervention for three months.Results
There was a significant decrease in body mass index (BMI), leptin, total cholesterol (TC), low density lipoprotein cholesterol (LDL-c), triglycerides(TG), homeostasis model assessment-insulin resistance- index (HOMA-IR) , beck depression inventory (BDI ) & profile of mood states(POMS) and increase in high density lipoprotein cholesterol (HDL-c) & Rosenberg self-esteem scale (RSES) of group (A) after treatments, but the changes of group (B) were not significant. Moreover, there were significant differences between mean levels of the investigated parameters of group (B) and group (A) at the end of the study.Conclusion
Physical training and dietary measures can be used as methods of choice for psychological wellbeing and biochemical modulation in obese type 2 diabetes patients. 相似文献79.
The use of fibers in cementitious composites yields numerous benefits due to their fiber-bridging capabilities in resisting cracks. Therefore, this study aimed to improve the shear-resisting capabilities of conventional concrete through the hybridization of multiple synthetic fibers, specifically on reinforced concrete structures in seismic-prone regions. For this study, 16 hybrid fiber-reinforced concretes (HyFRC) were developed from the different combinations of Ferro macro-synthetic fibers with the Ultra-Net, Super-Net, Econo-Net, and Nylo-Mono microfibers. These hybrids were tested under direct shear, resulting in improved shear strength of controlled specimens by Ferro-Ultra (32%), Ferro-Super (24%), Ferro-Econo (44%), and Ferro-Nylo (24%). Shear energy was further assessed to comprehend the effectiveness of the fiber interactions according to the mechanical properties, dosage, bonding power, manufactured material, and form of fibers. Conclusively, all fiber combinations used in this study produced positive synergistic effects under direct shear at large crack deformations. 相似文献
80.
Hamady Dieng Sudha Rajasaygar Abu Hassan Ahmad Che Salmah Md. Rawi Hamdan Ahmad Tomomitsu Satho Fumio Miake Wan Fatma Zuharah Yuki Fukumitsu Ahmad Ramli Saad Suhaila Abdul Hamid Ronald Enrique Morales Vargas Abdul Hafiz Ab Majid Nik Fadzly Nur Faeza Abu Kassim Nur Aida Hashim Idris Abd Ghani Fatimah Bt Abang Sazaly AbuBakar 《Acta tropica》2014
Despite major insecticide-based vector control programs, dengue continues to be a major threat to public health in urban areas. The reasons for this failure include the emergence of insecticide resistance and the narrowing of the spectrum of efficient products. Cigarette butts (CBs), the most commonly discarded piece of waste, also represent a major health hazard to human and animal life. CBs are impregnated with thousands of chemical compounds, many of which are highly toxic and none of which has history of resistance in mosquitoes. This study was performed to examine whether exposure to CB alters various biological parameters of parents and their progeny. We examined whether the mosquito changes its ovipositional behaviors, egg hatching, reproductive capacity, longevity and fecundity in response to CB exposure at three different concentrations. Females tended to prefer microcosms containing CBs for egg deposition than those with water only. There were equivalent rates of eclosion success among larvae from eggs that matured in CB and water environments. We also observed decreased life span among adults that survived CB exposure. Extracts of CB waste have detrimental effects on the fecundity and longevity of its offspring, while being attractive to its gravid females. These results altogether indicate that CB waste indirectly affect key adult life traits of Aedes aegypti and could conceivably be developed as a novel dengue vector control strategy, referring to previously documented direct toxicity on the larval stage. But this will require further research on CB waste effects on non-target organisms including humans. 相似文献