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Objectives: The present study was designed to evaluate the efficacy of Lactuca sativa (LS) Linn. (Asteraceae) against scopolamine-induced amnesia and to validate its traditional claim as memory enhancer.

Methods: Ethanol extract of fresh LS leaves (LSEE), standardized on the basis of quercetin content, was successively partitioned using various solvents viz., hexane, ethyl acetate, and n-butanol in increasing order of polarity. LSEE (50, 100, and 200?mg/kg) and its various fractions (at a dose equivalent to dose of LSEE exhibiting maximum activity), administered orally for 14 days, were evaluated for their memory enhancing effect against scopolamine-induced (1?mg/kg, i.p.) amnesia in 3–4 months old male Laca mice (n?=?6 in each group). The memory enhancing effect was evaluated using behavioural (elevated plus maze, novel object recognition and Morris water maze tests) and biochemical parameters (acetylcholinesterase activity, malonaldehyde, superoxide dismutase, nitrite, catalase, and reduced gultathione content). The results of the test substances were compared with both scopolamine and donepezil that was used as a standard memory enhancer and acetylcholinesterase inhibitor.

Results: Scopolamine elicit marked deterioration of memory and alteration in biochemical parameters in comparison to the control group. LSEE and its n-butanol and aqueous fractions significantly (P?n-butanol fraction (15?mg/kg) exhibited maximum anti-amnesic effect among various tested dose levels.

Discussion: The results exhibited that LS prophylaxis attenuated scopolamine-induced memory impairment through its acetylcholinesterase inhibitory and antioxidant activity validating its traditional claim.  相似文献   
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Surface morphology is an important indicator of malignant potential for solid-type lung nodules detected at CT, but is difficult to assess subjectively. Automated methods for morphology assessment have previously been described using a common measure of nodule shape, representative of the broad class of existing methods, termed area-to-perimeter-length ratio (APR). APR is static and thus highly susceptible to alterations by random noise and artifacts in image acquisition. We introduce and analyze the self-overlap (SO) method as a dynamic automated morphology detection scheme. SO measures the degree of change of nodule masks upon Gaussian blurring. We hypothesized that this new metric would afford equally high accuracy and superior precision than APR. Application of the two methods to a set of 119 patient lung nodules and a set of simulation nodules showed our approach to be slightly more accurate and on the order of ten times as precise, respectively. The dynamic quality of this new automated metric renders it less sensitive to image noise and artifacts than APR, and as such, SO is a potentially useful measure of cancer risk for solid-type lung nodules detected on CT.  相似文献   
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Various antiprotozoal drugs have been used to counteract the spread of giardiasis. However, due to increase in resistance to these compounds, there is an urgent need to find a natural biocompatible product to fight the pathogen in more healthy and effective way. The present study was designed to compare the therapeutic effect of probiotic Lactobacillus casei alone and in conjunction with antiprotozoal drugs on the outcome of giardiasis in murine model. BALB/c mice were challenged with Giardia intestinalis trophozoites, and 1 day after infection, these mice were treated with either probiotic alone or in conjunction with antiprotozoal drugs. Cyst, trophozoite, and lactobacilli counts were monitored vis-a-vis histopathological alterations in the small intestine. It was found that albendazole administered orally 1 day after Giardia infection was the most effective antiprotozoal drug among albendazole, tinidazole, metronidazole, and nitazoxanide. It reduced both the severity and duration of giardiasis. More specifically, oral administration of the probiotic L. casei in conjunction with albendazole further reduced the Giardia infection as was evident by the restored normal gut morphology. This suggests that probiotics and antiprotozoal drugs in combination may be the better alternative therapy for treatment of gastrointestinal diseases and enhanced recovery.  相似文献   
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Melioidosis is endemic in the South Asian regions, like Thailand, Singapore Malaysia and Australia. The disease is more pronounced in the southern part of the country. It is caused by Burkholderia pseudomallei which causes systemic involvement, morbidity and mortality associated with the disease is high. Due to highly varied clinical presentation, and low general awareness this infection is largely underdiagnosed and under reported in our country. Most laboratories in the country still rely on conventional culturing methods with their low sensitivity, adding to the under reporting. To enhance physician awareness we describe here two cases who presented to our institute after months of misdiagnosis.  相似文献   
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Acute myocardial infarction is responsible for a significant proportion of morbidity and mortality in patients with ischaemic heart disease. Apart from cardiogenic shock, important mechanical complications include myocardial rupture, mitral regurgitation, mural thrombosis, left ventricular true aneurysm and pericarditis. Such patients are likely to be older (more than 60 years of age), especially women with hypertension, single-vessel disease, first episode of transmural infarction, smaller area of infarction, and/or delayed thrombolytic therapy. The incidences of all these complications have significantly reduced due to availability of reperfusion techniques. Myocardial rupture includes rupture of the left ventricular free wall, interventricular septum or papillary muscles, which can occur within few hours or days after infarction and emergency surgery is indicated. Lateral displacement of papillary muscles due to post-infarctional left ventricular remodelling is the main factor for ischaemic mitral regurgitation; some patients would require mitral valve repair or replacement. Mural thrombosis results from an abnormal flow and local hypercoagulable state and requires thrombolytic therapy or even surgical excision. Post-infarctional fibrosis is also responsible for formation of ventricular apical aneurysms and depending on the clinical status, reconstructional surgery may be required. Dressler's syndrome is a rare occurrence of fibrinous pericarditis accompanied by constitutional symptoms, which responds to immunomodulation.  相似文献   
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One hundred volunteer female college teachers were selected from Jalandhar, Punjab, India. General obesity was found in 56.6%, 76.9%, and 76.2%, abdominal obesity in 56.6%, 57.7%, and 81.0%, of 30- to 39-year-old (Group I), 40- to 49-year-old, (Group II) and 50- to 59-year-old (Group III) participants, respectively. A significantly (p ≤ .05) lower mean value of uncontrolled eating domain was observed in the participants belonging to Group I in comparison to Groups II and III. The cognitive restraint was less in Group III (13.71%), followed by Group II (14.04%) and I (13.71%). The mean values of emotional eating domain revealed not much difference in Group I (12.19%), Group II (12.65%), and Group III (12.00%). Adiposity showed a significant (p ≤ .10, .05) relationship with age and eating behaviors. In conclusion, lesser cognitive dietary restraint and emotional eating were the variables associated with adiposity in the participants.  相似文献   
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