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排序方式: 共有1282条查询结果,搜索用时 15 毫秒
101.
Mostafazadeh B Farzaneh Sheikh E Afsharian Shishvan T Seraji FN Salmasian H 《Turkish neurosurgery》2008,18(3):228-231
Intracranial berry aneurysms are the most common kind of aneurysms in the brain, and are caused by head trauma in 1% of cases. They may remain asymptomatic for a long time or may rupture and cause intracranial hemorrhage. These aneurysms are associated with a high mortality rate. A definitive diagnosis can be made by angiography or autopsy. We studied the cadavers of 425 people who passed away accidentally. The number and location of berry aneurysms were recorded. Twelve cases (2.82%) were found to have a single berry aneurysm and two (0.47%) had multiple aneurysms. The aneurysms had a tendency to occur in the frontal half of the Circle of Willis and in approximation of the bifurcation of arteries. The main characteristics of cases of berry aneurysm in the Iranian population were in agreement with that reported in previous Western studies. 相似文献
102.
Sorond FA Lipsitz LA Hollenberg NK Fisher ND 《Neuropsychiatric Disease and Treatment》2008,4(2):433-440
BACKGROUND AND PURPOSE: Cerebral ischemia is a common, morbid condition accompanied by cognitive decline. Recent reports on the vascular health benefits of flavanol-containing foods signify a promising approach to the treatment of cerebral ischemia. Our study was designed to investigate the effects of flavanol-rich cocoa (FRC) consumption on cerebral blood flow in older healthy volunteers. METHODS: We used transcranial Doppler (TCD) ultrasound to measure mean blood flow velocity (MFV) in the middle cerebral artery (MCA) in thirty-four healthy elderly volunteers (72 +/- 6 years) in response to the regular intake of FRC or flavanol-poor cocoa (FPC). RESULTS: In response to two weeks of FRC intake, MFV increased by 8% +/- 4% at one week (p = 0.01) and 10% +/- 4% (p = 0.04) at two weeks. In response to one week of cocoa, significantly more subjects in the FRC as compared with the FPC group had an increase in their MFV (p < 0.05). CONCLUSIONS: In summary, we show that dietary intake of FRC is associated with a significant increase in cerebral blood flow velocity in the MCA as measured by TCD. Our data suggest a promising role for regular cocoa flavanol's consumption in the treatment of cerebrovascular ischemic syndromes, including dementias and stroke. 相似文献
103.
Sorond FA Schnyer DM Serrador JM Milberg WP Lipsitz LA 《Cortex; a journal devoted to the study of the nervous system and behavior》2008,44(2):179-184
Aging is associated with frontal subcortical microangiopathy and executive cognitive dysfunction, suggesting that elderly individuals may have impaired metabolic activation of cerebral blood flow to the frontal lobes. We used transcranial Doppler (TCD) ultrasound to examine the cerebral blood flow response to executive control and visual tasks in the anterior and posterior cerebral circulations and to determine the effects of healthy aging on cerebral blood flow regulation during cognitive tasks. Continuous simultaneous anterior cerebral artery (ACA) and posterior cerebral artery (PCA) blood flow velocities (BFVs) and mean arterial pressure (MAP) were measured in response to word stem completion (WSC) and a visual search (VS) task in 29 healthy subjects (14 young, 30+/-1.5 years; 15 old, 74+/-1.4 years). We found that: (1) ACA and PCA blood flow velocities are both significantly increased during WSC and VS cognitive tasks, (2) ACA and PCA activations were task specific in our young volunteers, with ACA>PCA BFV during the WSC task and PCA>ACA BFV during the VS task, (3) while healthy elderly subjects also had PCA>ACA BFV during the VS task, they did not have ACA>PCA activation during the WSC task, and (4) healthy elderly subjects tend to have overall greater increases in BFV during both cognitive tasks. We conclude that TCD can be used to monitor cerebrovascular hemodynamics during the performance of cognitive tasks. Our data suggest that there is differential blood flow increase in the ACA and PCA in young versus elderly subjects during cognitive tasks. 相似文献
104.
105.
NMDA receptors of dorsal hippocampus are involved in the acquisition, but not in the expression of morphine-induced place preference 总被引:1,自引:0,他引:1
Zarrindast MR Lashgari R Rezayof A Motamedi F Nazari-Serenjeh F 《European journal of pharmacology》2007,568(1-3):192-198
In the present study, involvement of the N-methyl-d-aspartate (NMDA) receptors of the CA1 region of dorsal hippocampus (intra-CA1) in the acquisition or expression of morphine-induced conditioned place preference in rats was studied. Male Wistar rats were used in these experiments. NMDA-receptor agonist (NMDA) and antagonist (MK-801) were injected into the CA1 region of the dorsal hippocampus (intra-CA1) and morphine was injected subcutaneously. An unbiased conditioned place preference paradigm was used to study the effect of these agents. In the first set of experiments, the drugs were used during the development of conditioned place preference by morphine or they were used alone in order to see if they induce conditioned place preference or conditioned place aversion. Our data showed that subcutaneous (s.c.) injection of morphine sulphate (2.5-10 mg/kg) induced conditioned place preference in rat. NMDA (0.1-1 microg/rat) or MK-801 (1-4 microg/rat) did not induce conditioned place preference or conditioned place aversion. Intra-CA1 administration of different doses of NMDA (0.1-1 microg/rat) increased, while MK-801 (1-4 microg/rat) decreased morphine-induced place preference. MK-801 reversed the effect of NMDA on morphine response. In the second set of experiments, when the drugs were used before testing on Day 5, in order to test their effects on the expression of morphine (7.5 mg/kg)-induced place preference, intra-CA1 administration of NMDA or MK-801 did not alter the morphine response. None of the drugs influenced locomotion. It is concluded that NMDA receptor of the CA1 region of hippocampus are involved in the acquisition but not expression of morphine-induced place preference. 相似文献
106.
107.
Hepatitis B virus (HBV) genotype and YMDD motif mutation profile among patients infected with HBV and untreated with lamivudine. 总被引:1,自引:0,他引:1
Samad Amini-Bavil-Olyaee Sayed Younes Hosseini Farzaneh Sabahi Seyed-Moayed Alavian 《International journal of infectious diseases》2008,12(1):83-87
OBJECTIVES: A few reports exist on hepatitis B virus (HBV) genotype distribution in Iran; however the sample sizes of these studies are insufficient. The first objective of this study was to determine the HBV genotype distribution with a large sample size (147 specimens). The second objective was to determine the incidence of the lamivudine-resistant YMDD mutant profile among HBV-infected patients not treated with lamivudine; some studies have reported that YMDD mutants are detectable even before antiviral treatment. METHODS: We used two cost-effective PCR-based methods that have been developed in-house: gap-PCR and artificially created restriction site-PCR (ACRS-PCR). Also, 11 samples were randomly selected and bi-directionally sequenced and subjected to phylogenetic analysis. RESULTS: Gap-PCR results revealed genotype D of HBV in all patients, and ACRS-PCR results disclosed the absence of mutation within the YMDD motif before antiviral therapy in the study population. Phylogenetic analysis supported the former genotyping results with the segregation of all Iranian HBV isolates in the genotype D branch with a high bootstrap value (99%, 1000 replicates). CONCLUSIONS: The present study using two cost-effective methods showed that genotype D of HBV is dominant among Iranian HBV-infected subjects, and HBV lamivudine-resistant strains do not exist naturally among Iranian patients not treated with lamivudine. 相似文献
108.
PEGylation of microspheres for therapeutic embolization: preparation, characterization and biological performance evaluation 总被引:1,自引:0,他引:1
In this study, microspheres designed for embolization, defined as GF2000-Trisacryl MS (GF-MS) and DEAE-Trisacryl MS (DEAE-MS), were originally PEGylated using (3-amino propyl) triethoxy silane as coupling agent. Indomethacin was loaded into both PEGylated and non-PEGylated DEAE-MS, displaying ion-exchange ability, through a batch process with a respective capacity of 1.2 and 0.25 g/g. The morphology of naked and PEGylated MS was evaluated by scanning electron microscopy (SEM). Both micosphere resins surface looked like orange skin, although DEAE-MS showed a slightly rougher surface due to the copolymerization process. PEGylated microspheres have a most likely swelling surface owing to the presence of PEG hydrophilic chains. The mean diameters were of about 66 and 60 microm for GF-MS and DEAE-MS, respectively. Data obtained for PEGylated MS by Fourier Transform Infrared spectroscopy (FTIR) confirmed that microspheres were successfully PEGylated. Finally, complement activation in vitro was performed to evaluate the activating capacity of different microspheres. Both PEGylated GF-MS and DEAE-MS activated the complement system of about 33% less than their corresponding naked microspheres, while loading PEGylated DEAE-MS with indomethacin almost suppressed complement activation. This inhibiting role implies that PEGylation as well as loading the microspheres with anti-inflammatory drug has a compact effect on the interaction of microspheres with blood proteins. 相似文献
109.
Farzaneh Mohammadzadeh Rostami Hadis Mousavi Morteza Rabi Nezhad Mousavi Milad Shahsafi 《Clinical Microbiology Newsletter》2018,40(12):97-103
Deaths from infectious diseases and deep concerns about increases in microbial resistance make it necessary for scientists to develop innovative therapeutic solutions and complementary therapies. Growing evidence is available on the therapeutic effects of probiotics. There are also documents about the beneficial effects of probiotics, but it is difficult to draw a definitive conclusion regarding the results of these studies because of the small sample size, the limitations of the study methods, and the use of different strains of probiotic bacteria. This review study summarizes the articles available on the scientific and electronic databases Embase, Medline, and Scopus until the end of 2017, including case studies describing beneficial microbes as tools for improving the process of controlling infectious diseases. Until the development of novel vaccines or other approaches occurs, the use of probiotics seems to be a logical way to attempt to control certain infectious diseases. 相似文献
110.
Rasoul Pourebrahim Hossein Fakhrzadeh Fatemeh Bandarian Ozra Tabatabaie Masoomeh Noori Forouzan Djalilpour Farzaneh Zahedi Iman Rahimi Ramin Heshmat Ebrahim Djavadi Sara Ghotbi Bagher Larijani 《European journal of cardiovascular prevention and rehabilitation》2006,13(2):229-235
BACKGROUND: A parental history of cardiovascular disease has a strong relationship with risk factor clusters in the offspring. This study was performed to identify major cardiovascular risk factors in middle school-aged children and their parents in both high and low-risk families. DESIGN: A school-based, cross-sectional study. METHODS: The middle schools of the 6th district of Tehran were divided randomly into two groups. A total of 169 high-risk children with their families were recruited from the first group and 105 low-risk children with their families were recruited from the second group of schools. Anthropometric and metabolic measurements were performed. RESULTS: The means of the waist circumference and waist-to-hip ratio were significantly higher in high-risk fathers. The means of total and low-density lipoprotein (LDL) cholesterol were significantly higher in both parents and children of the high-risk group. The means of the fasting plasma glucose were significantly higher in fathers and offspring of high-risk families. More fathers in high-risk families were smokers. The prevalence of increased total cholesterol, LDL-cholesterol and hyperglycemia (> or = 100 mg/dl) were higher in high-risk parents and children. The prevalence of increased body mass index (> or = 25 kg/m for parents and 85th percentile for children) was higher in fathers and children of high-risk families. CONCLUSIONS: Cardiovascular risk factors are more prevalent and clustered in high-risk families. The screening of high-risk families is essential to prevent the progression of atherosclerosis from childhood and reduce the burden of cardiovascular disease in adulthood. 相似文献