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31.

Background

Laparoscopic Roux en-Y gastric bypass (LRYGB) achieves sustained long-term weight loss and reduced mortality in morbidly obese patients. It is routinely performed using an ante- or retrocolic approach with the jejuno-jejunostomy constructed in the infracolic compartment. We have modified the standard technique of performing LRYGB by constructing both anastomoses in the supracolic compartment. This study describes the outcomes of consecutive primary LRYGB performed using this novel retrocolic–supracolic approach.

Methods

Data were prospectively collected on consecutive primary LRYGB performed in a tertiary-referral Bariatric Centre in the United Kingdom from September 2009 to March 2013. Data included demographics, operative outcomes (duration of surgery, postoperative anastomotic leak/bleeding/reoperations), development of strictures, length of stay, excess weight loss (EWL) and resolution of diabetes mellitus.

Results

Hand-sewn LRYGB was successfully performed using the retrocolic–supracolic approach in 300 of 307 (98 %) consecutive patients (72 % female). Median (IQR) age, weight and baseline body mass index were 49 (41–56) years, 146 (134–163) kg and 52.9 (48.8–57.2) kg/m2, respectively. There were 4 (1.3 %) anastomotic leaks and 8 (2.6 %) postoperative bleeds. The 30-day reoperation rate was 1.6 %. Median (IQR) hospital stay was 2 (2–2) days. Postoperative dysphagia requiring endoscopic balloon dilatation occurred in 19 (6.3 %) patients. Mean ± SD 12-month EWL was 69.9 ± 19.0 %. Within the follow-up period, 81 % of patients with type II diabetes mellitus achieved remission and 19 % reduced dosage of diabetes medication.

Conclusions

LRYGB performed using the retrocolic–supracolic approach was safe, feasible, technically advantageous and resulted in clinical outcomes akin to the standard infracolic approach.
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Cardiovascular disease (CVD) is the leading cause of death worldwide, and due to the lack of early detection techniques, the incidence of CVD is increasing day by day. In order to address this limitation, a knowledge based system with embedded intelligent heart sound analyser (KBHSA) has been developed to diagnose cardiovascular disorders at early stages. The system analyses digitized heart sounds that are recorded from an electronic stethoscope using advanced digital signal processing and artificial intelligence techniques. KBHSA takes into account data including the patient's personal and past medical history, clinical examination, auscultation findings, chest x-ray and echocardiogram, and provides a list of diseases that it has diagnosed. The system can assist the general physician in making more accurate and reliable diagnosis under emergency conditions where expert cardiologists and advanced equipment are not readily available. To test the validity of the system, abnormal heart sound samples and medical data from 40 patients were recorded and analysed. The diagnoses made by the system were counter checked by four senior cardiologists in Malaysia. The results show that the findings of KBHSA coincide with those of cardiologists.  相似文献   
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The present study demonstrated the systematic adaptation of quality by design-integrated approach for the development of novel nanostructured lipid carrier (NLC) of an anti-hypertensive drug isradipine (ISD) to address the inherent challenges such as low solubility and low oral bioavailability. Plackett-Burman design was used for preliminary screening of significant process and formulation variables (p <0.05), which were further processed using Box-Behnken design for the attainment of optimization goal that is, mean particle size (85.7 ± 7.3 nm), drug entrapment efficiency (87.4 ± 3.29%), and in vitro drug release characteristics (92.89 ± 5.47%). The optimized ISD-NLC formulation also demonstrated well-dispersed uniform-shaped particles (polydispersity index 0.207 ± 0.029), high gastrointestinal fluid stability (zeta potential ?10.17 ± 0.59 mV), and higher in vitro gut permeation (21.69 ± 2.38 μg/cm2 of ISD-NLC as compared to 11.23 ± 1.74 μg/cm2 in ISD suspension). Furthermore, lipolysis studies were performed for the purpose of in vivo fate, and significantly higher drug content of ISD from ISD-NLC in aqueous phase was found (72.34 ± 4.62%) as compared to drug suspension (3.01 ± 0.91%). Relative bioavailability of ISD-NLC and ISD suspension was increased by 4.2-fold and 1.78-fold in the absence and presence of cycloheximide which is a lymphatic uptake inhibitor revealing lymphatic uptake of ISD-NLC in bioavailability improvement. Hence, systematic adaptation of quality by design integrated approach improved gut permeation and potential solubilizaton fate (dynamic lipolysis) of ISD-NLC, which further improved the lymphatic uptake and biodistribution of drug thereby promisingits in vivo prospect and clinical efficacy.  相似文献   
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The study evaluated the hepatoprotective activity of plant extracts of cinnamon and glycyrrhizin in distinct dosage ways to minimize the oxidative stress induced by carbon tetrachloride (CCl4) in BALB/cJ inbred albino mice. Fifteen albino mice were divided into five groups, each group containing three mice. Group A was referred as positive control while group B, C, D and E were injected intraperitoneally with 1 mL/kg body weight of CCl4 twice a week for 1 month. Group C and D were treated orally with isolated extracts of cinnamon @50 mg/kg and glycyrrhizin @50 mg/kg respectively on daily basis for 1 month. However, group E was treated orally with combination dose of cinnamon @50 mg/kg + glycyrrhizin @50 mg/kg body weight. The increase in the levels of alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP), triglyceride (TG), malondialdehyde (MDA) and glucose were recorded in CCl4 induced liver injury in mice while there is decrease in the levels of total protein (TP), reduced glutathione (GSH), Superoxide dismutase (SOD) and catalase (CAT) in CCL4 intoxicated mice. Isolated therapy of plant extracts of cinnamon and glycyrrhizin decreased the levels of ALT, AST, ALP, MDA, TG and glucose whereas increase in TP, GSH, SOD and CAT was observed in plant extracts treated mice. The best restoration of all the above said parameters near to control was observed in group of mice treated with combination dose of cinnamon and glycyrrhizin @50 mg/kg. Therefore, the present study declared the antioxidative, anti-inflammatory and hepatoprotective activity of standardized extracts of cinnamon and glycyrrhizin and their potent defensive property.

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To avoid time-consuming, costly, and laborious experimental tests that require skilled personnel, an effort has been made to formulate the depth of wear of fly-ash concrete using a comparative study of machine learning techniques, namely random forest regression (RFR) and gene expression programming (GEP). A widespread database comprising 216 experimental records was constructed from available research. The database includes depth of wear as a response parameter and nine different explanatory variables, i.e., cement content, fly ash, water content, fine and coarse aggregate, plasticizer, air-entraining agent, age of concrete, and time of testing. The performance of the models was judged via statistical metrics. The GEP model gives better performance with R2 and ρ equals 0.9667 and 0.0501 respectively and meet with the external validation criterion suggested in the previous literature. The k-fold cross-validation also verifies the accurateness of the model by evaluating R2, RSE, MAE, and RMSE. The sensitivity analysis of GEP equation indicated that the time of testing is the influential parameter. The results of this research can help the designers, practitioners, and researchers to quickly estimate the depth of wear of fly-ash concrete thus shortening its ecological susceptibilities that push to sustainable and faster construction from the viewpoint of environmentally friendly waste management.  相似文献   
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