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61.
Intersymbol interference (ISI) degrades the bit error rate (BER) performance of sequential detectors such as maximum likelihood sequence detection (MLSD) and the maximum a posteriori (MAP) algorithm due to minimum distance reduction. This paper describes a novel rotation method that can increase the minimum distance and results in significant improvement in the BER performance for binary PSK and 4QAM systems when operating over severe ISI channels. Simulation results show that this method can improve the BER performance of systems employing MLSD and MAP turbo equalization by up to 4.6 dB compared to existing approaches including known precoding schemes.  相似文献   
62.
Urinary iodine was estimated chemically by the kinetic method, after mineralisation of the organic iodide by alkaline ashing. The experimental conditions were optimised. The methodological modifications of an existing technique are highlighted. Urinary iodine levels were determined in 349 school children of Bombay, of whom 163 had Grade IA/IB/II goitre and the remaining 186 did not have goitre. Urinary iodine concentration (Mean±SEM) of the control (n=186) and the goitre (n=163) groups were 76.47±4.97 and 71.09±6.23 μg/g creatinine respectively. The difference in the means was statistically not significant. Urinary iodine exhibited a log-normal distribution. It is concluded that the presence of goitre in the clinically euthyroid group of children was not caused by iodine deficiency.  相似文献   
63.
Curcuma longa commonly known as tumeric is traditionally used as a spice in Indian food. A wide range of biological activities e.g. anticancer, antimicrobial, antiinflammatory and free radical scavenging activity of the plant suggests a logical basis for its traditional use in foodstuff. Various phytothreapeutic uses ofCurcuma longa have been reviewed.  相似文献   
64.
In the present study the antioxidative potential ofMomordica charantia, Azadirachta indica, Allium sativum andOcimum sanctum was assessed in streptozotocin induced diabetic rats. Lipid peroxide levels were also measured in normal, diabetic and treated animals. Malondialdehyde (MDA) levels were significantly higher and antioxidant activity was found low in diabetic groups as compared to the control groups, and significant alteration in both the MDA levels and antioxidant activity was also observed when the above herbal hypoglycemic agents were given to diabetic rats. On the basis of our results we conclude thatM. charantia, A. indica, A. sativum andO. sanctum are not only useful in controlling the lipid peroxide levels but are also helpful in further strengthening the antioxidant potential.  相似文献   
65.

Objective

This study involves a reanalysis of data from a randomized controlled trial to examine whether child-parent psychotherapy (CPP), an empirically based treatment focusing on the parent-child relationship as the vehicle for child improvement, is efficacious for children who experienced multiple traumatic and stressful life events (TSEs).

Methods

Participants comprised 75 preschool-aged children and their mothers referred to treatment following the child's exposure to domestic violence. Dyads were randomly assigned to CPP or to a comparison group that received monthly case management plus referrals to community services and were assessed at intake, posttest, and 6-month follow-up. Treatment effectiveness was examined by level of child TSE risk exposure (<4 risks versus 4+ TSEs).

Results

For children in the 4+ risk group, those who received CPP showed significantly greater improvements in PTSD and depression symptoms, PTSD diagnosis, number of co-occurring diagnoses, and behavior problems compared to those in the comparison group. CPP children with <4 risks showed greater improvements in symptoms of PTSD than those in the comparison group. Mothers of children with 4+ TSEs in the CPP group showed greater reductions in symptoms of PTSD and depression than those randomized to the comparison condition. Analyses of 6-month follow-up data suggest improvements were maintained for the high risk group.

Conclusions

The data provide evidence that CPP is effective in improving outcomes for children who experienced four or more TSEs and had positive effects for their mothers as well.

Practice implications

Numerous studies show that exposure to childhood trauma and adversity has negative consequences for later physical and mental health, but few interventions have been specifically evaluated to determine their effectiveness for children who experienced multiple TSEs. The findings suggest that including the parent as an integral participant in the child's treatment may be particularly effective in the treatment of young children exposed to multiple risks.  相似文献   
66.
During post-analytical phase, critical value notification to responsible caregiver in a timely manner has potential to improve patient safety which requires cooperative efforts between laboratory personnel and caregivers. It is widely accepted by hospital accreditors that ineffective notification can lead to diagnostic errors that potentially harm patients and are preventable. The objective of the study was to assess the variables affecting critical value notification, their role in affecting it’s quality and approaches to improve it. In the present study 1,187 critical values were analysed in the Clinical Chemistry Laboratory catering to tertiary care hospital for neuropsychiatric diseases. During 25 months of study period, we evaluated critical value notification with respect to clinical care area, caregiver to whom it was notified and timeliness of notification. During the study period (25 months), the laboratory obtained 1,279 critical values in clinical chemistry. The analytes most commonly notified were sodium and potassium (20.97 & 20.8 % of total critical results). Analysis of critical value notification versus area of care showed that critical value notification was high in ICU and emergency area followed by inpatients and 64.61 % critical values were notified between 30 and 120 min after receiving the samples. It was found that failure to notify the responsible caregiver in timely manner represent an important patient safety issue and may lead to diagnostic errors. The major area of concern are notification of critical value for outpatient samples, incompleteness of test requisition forms regarding illegible writing, lack of information of treating physician and location of test ordering and difficulty in contacting the responsible caregiver.  相似文献   
67.
As a stress agent, inducing apoptosis and blocking it, Cd can have both helpful and harmful effects. The atmosphere is a thin envelope which makes the worid a global village. Cd is the most toxic metal in air. As both the first and second messenger of the stress response, it is synergistically toxic with all other stressors, including many other carcinogens. Elimination of Pb and its replacement with added benzene in gasoline appears to have increased the toxicity of atmospheric Cd. With scientific understanding of the molecular basis of Cd's role in carcinogenesis and anti-carcinogenesis, primary cancer prevention can be practiced by reducing Cd and chemical air pollution and educating the public on smoke cessation, healthy eating habits and stress reduction. Using the existing information on Cd and its effects, determinations could be made on established cancers so that individualized treatment protocols can be developed to improve patient care.  相似文献   
68.
Despite enormous research in the field of hypertension, its pathophysiology still remains largely unresolved and appears to be multifactorial. In the present communication, we have analyzed the status of nitric oxide (NO) in the patients with essential hypertension and age matched controls. We have found that the levels of NO are lowered in essential hypertension. The normalization of blood pressure by administration of antihypertensive therapy causes rise in the NO level indicating that perturbed NO status in essential hypertension is reversible. Addition of antioxidant to the antihypertensive drugs causes a further, though non significant, rise in the levels of NO, suggesting that antioxidants may be combined with antihypertensive drugs as adjunct in the management of essential hypertension.  相似文献   
69.
Regulation of intracellular cholesterol homeostasis exists under balance between intracellular biosynthesis and uptake from extracellular origin by cell surface transport proteins. Expected role of cholesterol on either tumor suppressor gene and/or DNA synthesis has been aimed in the present study to explore intracellular cholesterol homeostasis in CLL subjects. Higher expressions of p53R2 (p53 dependent subunit of ribonucleotide reductase) and p53 were found in lymphocytes of chronic human lymphocytic leukemia as comparison to their normal counterparts. Inverse relation was found with p53 independent R2 subunit (in human hRRM2) of ribonucleotide reductase, which was found to be decreased from its control group. More expression of peripheral type benzodiazepine receptor, a cholesterol transporter, was noticed in isolated nuclear fraction with simultaneous increase of cholesterol concentration in cytoplasmic and nuclear compartments. A parallel increase of cholesterol in cell nucleus with increased p53R2 expression shows priority of the involvement of cholesterol in the process of cell replication.  相似文献   
70.
We investigated the effect of cholesterol and the metalloporphyrins cobalt mesoporphyrin (CoMP) and chromium protoporphyrin (CrPP) on phospholipase A2 (PLA2) activity and the consequent hepatic mitochondrial stability as well as on lipid concentrations. Our studies revealed that on administration of cholesterol, CrPP, CoMP as well as simultaneous adminstration of cholesterol and CrPP, there was an inhibition of PLA2 activity. These moieties may therefore, be agents for preventing destabilisation of the mitochondrial membrane and the consequent pathological conditions which may arise due to membrane lysis. Our results revealed that cholesterol administration increased phospholipid concentration, albeit by modest amounts. Although the independent administration of metalloporphyrins led only to minor elevations in phospholipid concentration, the simultaneous administration of cholesterol and CrPP generated a steep elevation in the concentration of total phospholipid. Since cholesterol inhibits PLA2 activity it has the potential of being therapeutic agent for preventing the pathological conditions which may arise due to membrane lysis.  相似文献   
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