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81.

Background

Obesity is associated with increased cardiovascular morbidity and mortality. A direct effect of isolated obesity on cardiac function is not well established. The study was designed to determine the direct effect of various grades of isolated obesity on echocardiographic indices of systolic and diastolic left ventricular function.

Methods

Fifty one obese and 25 normal weight, serving personnel without any other pathological condition were studied. Group I (n=25) consisted of subjects with normal weight and body mass index (BMI <25kg/m2), Group II (n=34) of overweight subjects (BMI 25-29.9 kg/m2) and Group III (n=17) of obese subjects (BMI >30 kg/m2). Echocardiographic indices of systolic and diastolic function were obtained and dysfunction was assumed when at least two values differed by ≥ 2 SD from the normal weight group.

Result

Ejection fraction, fractional shortening were increased (p<0.05) in Group II and III. Left ventricular dimensions were increased (p< 0.001) but relative wall thickness was unchanged. Systolic dysfunction was not observed in any of the obese patients. The mitral valve pressure half time (p< 0.01), left atrial diameter (p < 0.01) and the deceleration time were increased (p< 0.01) in obese subjects, while other diastolic variables were unchanged. No difference were found between obesity subgroups. Subclinical diastolic dysfunction was more prevalent among obese subjects. BMI correlated significantly with indices of left ventricular systolic and diastolic function.

Conclusion

Subclinical left ventricular diastolic dysfunction was noted in all grades of obesity which correlates with BMI.Key Words: Obesity, Systolic function, Diastolic function, Echocardiography  相似文献   
82.

Background:

Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation.

Materials and Methods:

Twenty-two children (18 boys, 4 girls) aged 6-16 years with recent (> 3 days) femoral diaphyseal fractures (20 closed, 2 open) were stabilized with Titanium Elastic Nail (TEN). These fractures were in proximal third (n=3), middle third (n=15) and in the distal third (n=4) 17 patients underwent surgery within seven days of their injury. The results were evaluated using Flynn''s scoring criteria. Statistical analysis was done using Fischer''s exact test.

Results:

All 22 patients were available for evaluation after a mean of 26 months (14-36 months) of followup. Radiological union in all cases were achieved in a mean time of 8.7 weeks. Full weight bearing was possible in a mean time of 8.8 weeks. Mean duration of hospital stay was 9.8 days. The results were excellent in 13 patients (59.0%), successful in six (27.2%) and poor in three patients (13.6%). All patients had early return to school.

Conclusion:

Intramedullary fixation titanium elastic nailing is an effective treatment of diaphyseal fractures of the femur in properly selected patients of the 6-16 years age group.  相似文献   
83.
Hyperlipidemia is a major risk factor for the premature development of coronary heart disease and it has been shown to increase the incidence of myocardial ischemia and cardiac events. Pentacyclic triterpenes possess antiatherosclerotic, antioxidant, anti-inflammatory and cytoprotective effects. To study the effect of plant derived triterpene, lupeol and its ester lupeol linoleate, on lipid status and biochemical changes on heart tissue, male albino Wistar rats were fed high-cholesterol diet (normal rat chow supplemented with 4% cholesterol and 1% cholic acid; HCD) for 30 days. There was a significant (p<0.001) increase in the levels of total cholesterol, triglycerides and phospholipids along with augmented activities of lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase in the heart tissue. Triterpenes treatment reduced the above alterations produced in hypercholesterolemic rats. The transmembrane enzymes, namely Na(+), K(+)-ATPase, Ca(2+)-ATPase and Mg(2+)-ATPase showed a decrease in their activities. Triterpenes treatment reversed these levels, prevented the hypertrophic cardiac histology and restored the normal ultrastructural architecture. In conclusion, lupeol and lupeol linoleate intervention minimized the lipid abnormalities and abnormal biochemical changes induced by HCD fed rats. This shows that triterpenes possess cardioprotective effects which will be beneficial in hypercholesterolemic condition. Out of these two triterpenes tested, lupeol linoleate appeared to be even more effective than lupeol.  相似文献   
84.
85.
Gellan gum (GG)‐based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine‐tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG‐MA) and high‐acyl gellan gums (HA‐GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA‐GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA‐GG content induced greater weight loss in the GG‐MA/HA‐GG formulation compared to GG‐MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein‐AM and ATP assays. Results showed that tunable GG‐MA/HA‐GG hydrogels were non‐cytotoxic and supported viability of rabbit NP cells. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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88.

Aim

To investigate whether participation in a clinical audit and education session would improve GP management of patients who smoke.

Methods

GPs who participated in an associated smoking cessation research program were invited to complete a three-stage clinical audit. This process included a retrospective self-audit of smoking cessation management practices over the 6 months prior to commencing the study, attending a 2.5 hour education session about GP management of smoking cessation, and completion of a second retrospective self-audit 6 months later. Twenty-eight GPs completed the full audit and education process, providing information about their smoking cessation management with 1114 patients. The main outcome measure was changes in GP management of smoking cessation with patients across the audit period, as measured by the clinical audit tool.

Results

The majority of GPs (57%) indicated that as a result of the audit process they had altered their approach to the management of patients who smoke. Quantitative analyses confirmed significant increases in various forms of evidence-based smoking cessation management practices to assist patients to quit, or maintain quitting across the audit period. However comparative analyses of patient data challenged these findings, suggesting that the clinical audit process had less impact on GP practice than suggested in GP's self-reported audit data.

Conclusion

This study provides some support for the combined use of self-auditing, feedback and education to improve GP management of smoking cessation. However further research is warranted to examine GP- and patient-based reports of outcomes from clinical audit and other educational interventions.  相似文献   
89.

Background

The aim of this study was to assess the role of middle cerebral artery peak systolic velocity (MCA-PSV), as measured by doppler ultrasound, in detecting foetal anaemia in Rh- isoimmunised pregnancies. Intra-uterine foetal blood transfusion was performed in such anaemic foetuses to tide over the crisis of foetal immaturity till considered fit for extra-uterine survival.

Methods

Rh-isoimmunised pregnancies reporting to a tertiary institute from 2003 to 2005, were screened by doppler ultrasound to estimate MCA-PSV to detect foetal anaemia. If the foetus developed MCA-PSV of more than 1.5 multiple of median (MoM) for the gestational age, foetal blood sampling through cordocentesis was performed to confirm foetal anaemia, followed by intrauterine foetal blood transfusion to all anaemic foetuses at the same sitting. Neonatal outcome was evaluated by recording gestational age at the time of delivery, duration of gestational time gained and need for blood transfusion in the neonatal period.

Results

A total of thirteen isoimmunised pregnancies were evaluated. Three pregnancies did not require in-utero foetal blood transfusion. Twenty-one intrauterine foetal blood transfusions were performed in the remaining ten patients. Five received blood transfusion in the neonatal period. Intra uterine foetal death occurred in one grossly hydropic foetus and favourable neonatal outcome was recorded in the rest.

Conclusion

The clinical outcome of these pregnancies justifies the use of doppler studies of MCA-PSV in detecting foetal anaemia and intra uterine foetal blood transfusion is the only hope of prolonging pregnancy and salvaging such foetuses.Key Words: Rh-isoimmunisation, Middle cerebral artery peak systolic velocity, Foetal anaemia, Foetal blood transfusion  相似文献   
90.
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