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71.
72.
M Tariq  A M Ageel  N S Parmar 《Toxicon》1986,24(1):101-103
Administration of endotoxin, a lipopolysaccharide extracted from cell walls of gram negative bacteria, elicited alterations in various metabolic parameters and in the electrocardiogram of rats. Cardiac glycogen and serum glucose were decreased, while serum pyruvate and acid phosphatase levels were increased. There was initial tachycardia followed by significant bradycardia and elevation of the ST segment in the animals with shock. Erythrocyte count, haemoglobin and haematocrit were not changed after shock. Treatment with naloxone caused significant decreases in the metabolic and electrocardiographic changes induced by endotoxin.  相似文献   
73.
Graphene is a 2D material with remarkable properties. The present study demonstrates the fabrication of a graphene-based sensor for measuring the temperature and humidity of a metal body. The graphene sensor was fabricated by depositing a thin film of graphene nanoparticles between silver electrodes (separated by ∼50 μm) on a glass substrate. The graphene thin film was characterized by XRD, Raman spectroscopy and UV-vis techniques. The capacitance and resistance for both the relative humidity (in the range of 0–100% RH) and temperature (in the range of 230–310 K) were measured using an LCR meter at 1 kHz in a controlled chamber. The graphene-based sensor expressed high sensitivity with fast response and recovery times for both humidity and temperature with long stability and low hysteresis curves. The sensor was also tested on a metal body, which expressed a good response time. Moreover, the measured data of capacitance and resistance was analyzed with classical and neutrosophic analysis as an application of modern material statistics. It was observed that neutrosophic analysis is more flexible for analyzing the capacitance and resistance of the fabricated sensor.

Graphene is a 2D material with remarkable properties.  相似文献   
74.
PURPOSE: To establish a baseline of phase differences between tissues in a number of regions of the human brain as a means of detecting iron abnormalities using magnetic resonance imaging (MRI). MATERIALS AND METHODS: A fully flow-compensated, three-dimensional (3D), high-resolution, gradient-echo (GRE) susceptibility-weighted imaging (SWI) sequence was used to collect magnitude and phase data at 1.5 T. The phase images were high-pass-filtered and processed region by region with hand-drawn areas. The regions evaluated included the motor cortex (MC), putamen (PUT), globus pallidus (GP), caudate nucleus (CN), substantia nigra (SN), and red nucleus (RN). A total of 75 subjects, ranging in age from 55 to 89 years, were analyzed. RESULTS: The phase was found to have a Gaussian-like distribution with a standard deviation (SD) of 0.046 radians on a pixel-by-pixel basis. Most regions of interest (ROIs) contained at least 100 pixels, giving a standard error of the mean (SEM) of 0.0046 radians or less. In the MC, phase differences were found to be roughly 0.273 radians between CSF and gray matter (GM), and 0.083 radians between CSF and white matter (WM). The difference between CSF and the GP was 0.201 radians, and between CSF and the CN (head) it was 0.213 radians. For CSF and the PUT (the lower outer part) the difference was 0.449 radians, and between CSF and the RN (third slice vascularized region) it was 0.353 radians. Finally, the phase difference between CSF and SN was 0.345 radians. CONCLUSION: The Gaussian-like distributions in phase make it possible to predict deviations from normal phase behavior for tissues in the brain. Using phase as an iron marker may be useful for studying absorption of iron in diseases such as Parkinson's, Huntington's, neurodegeneration with brain iron accumulation (NBIA), Alzheimer's, and multiple sclerosis (MS), and other iron-related diseases. The phases quoted here will serve as a baseline for future studies that look for changes in iron content.  相似文献   
75.
In the past, many studies have been conducted on the optimization of reinforced concrete (RC) structures. These studies have demonstrated the effectiveness of different optimization techniques to obtain an economical design. However, the use of optimization techniques to an obtain economical design is not so practical due to the difficulty in applying most of the optimization techniques to achieve an optimal solution. The RC beam is one of the most common structural elements encountered by a practising design engineer. The current study is designed to highlight the potential of the Solver tool in MS Excel as an easy-to-use option for optimizing the design of simply supported RC beams. A user-friendly interface was developed in a spreadsheet in which beam design parameters from a typical design can be entered and an economical design can be obtained using the Evolutionary Algorithm available in the MS Excel Solver tool. To demonstrate the effectiveness of the developed optimization tool, three examples obtained from the literature have been optimized. The results showed that up to 24% economical solution can be obtained by keeping the same material strengths that were assumed in the original design. However, if material strength is also considered as a variable, up to 44% of the economical solution can be obtained. A parametric study was also conducted to investigate the effect of different design variables on the economical design of simply supported RC beams and to derive useful rules of thumb for their design and proportioning, with the objective of cost minimization. The results of the parametric study suggest that the grade of the reinforcing steel is one of the most influential factors that affect the cost of simply supported RC beams. Practicing engineers can use the trends derived from this research to further refine their optimal designs.  相似文献   
76.
Herein, we synthesized the zinc oxide (ZnO) thin films (TFs) deposited on glass substrates via spray pyrolysis (SP) to prepare self-cleaning glass. Various process parameters were used to optimize photocatalytic performance. Substrates were coated at room temperature (RT) and 250 °C with a 1 mL or 2 mL ZnO solution while maintaining a distance from the spray gun to the substrate of 20 cm or 30 cm. Several characterization techniques, i.e., XRD, SEM, AFM, and UV–Vis were used to determine the structural, morphological, and optical characteristics of the prepared samples. The wettability of the samples was evaluated using contact angle measurements. As ZnO is hydrophilic in nature, the RT deposited samples showed a hydrophilic character, whereas the ZnO TFs deposited at 250 °C demonstrated a hydrophobic character. The XRD results showed a higher degree of crystallinity for samples deposited on heated substrates. Because of this higher crystallinity, the surface energy decreased, and the contact angle increased. Moreover, by using 2 mL solution, better surface coverage and roughness were obtained for the ZnO TFs. However, by exploiting the distance of the spray to the samples size distribution and surface coverage can be controlled, the samples deposited at 30 mL showed a uniform particle size distribution from 30–40 nm. In addition, the photoactivity of the samples was tested by the degradation of rhodamine B dye. Substrates prepared with a 2 mL solution sprayed at 20 cm showed higher dye degradation than other samples, which can play a vital role in self-cleaning. Hence, by changing the said parameters, the ZnO thin film properties on glass substrates were optimized for self-cleaning diversity.  相似文献   
77.

Background

Biliopancreatic diversion with duodenal switch (DS) is known to be superior in weight loss to other bariatric procedures, but with the disadvantage of increased complication rates. Single-anastomosis duodenal-ileal bypass (SADI-S) is reported to have similar weight loss with lower complication rates compared with traditional DS.

Objectives

The aim of this study was to compare weight loss and complication rate between SADI-S and double-anastomosis DS at a single institution.

Setting

Academic hospital, United States.

Methods

A retrospective chart review was performed on 185 patients who underwent laparoscopic or robot-assisted laparoscopic DS between March 1, 2015 and December 10, 2017. A total of 111 patients had SADI-S, and 74 patients underwent double-anastomosis DS.

Results

Baseline patient characteristics were comparable between the 2 groups. The mean preoperative body mass index was 56.3 kg/m2 and 54.4 kg/m2 in SADI-S and double-anastomosis DS patients, respectively. Thirteen (11.7%) and 4 (5.4%) patients were readmitted within 30 days after SADI-S and double-anastomosis DS, respectively (P?=?.16). Percentage of total weight loss was 22.0%, 38.5%, and 44.2% in the SADI-S group and 20.2%, 38.0%, and 48.4% in the double-anastomosis DS group at 6, 12, and 24 months, respectively. The majority of patients had vitamin A and E levels in the normal range. However, 40% to 60% of the patients had low levels of vitamin D after the procedure.

Conclusions

SADI-S and double-anastomosis DS are comparable in terms of weight loss and complication rate. However, close nutritional follow-up is warranted for both procedures.  相似文献   
78.

Background

The objective of this study was to analyze systematically the randomized, controlled trials that compared single-incision laparoscopic cholecystectomy (SILC) and conventional laparoscopic cholecystectomy (CLC).

Methods

The meta-analysis was conducted according to the Quality of Reporting of Meta-analysis (QUORUM) standards. The included studies were analyzed systematically using the statistical software package RevMan. The summated outcomes were expressed as the risk ratios (RR) for dichotomous variables and standardized mean differences (SMD) for continuous variables.

Results

Eleven randomized trials encompassing 858 patients were retrieved from the electronic databases. In the random effects model, postoperative pain, postoperative complications, length of hospital stay, cosmesis score, conversion rate, and time to return to normal activities were statistically comparable between the two cholecystectomy techniques. SILC was associated with a longer operating time [SMD 0.71; 95?% confidence interval (CI) 0.38, 1.05; z?=?4.18; p?<?0.0001) and an increased requirement for additional port insertion (RR 6.54; 95?% CI 2.19, 19.57; z?=?3.36; p?<?0008). However, there was significant heterogeneity among the trials.

Conclusions

SILC does not offer any advantage over CLC for treating benign gallbladder disorders. CLC may be used assiduously for this purpose.  相似文献   
79.
80.
A systematic review of randomised, controlled trials investigating the effectiveness of fibrin glue (FG) in reducing the postoperative seroma and seroma related morbidities following breast and axillary surgery was conducted. FG failed to influence the incidence of postoperative seroma, average volume of seroma, wound infection, complications and length of hospital stay in patients undergoing breast cancer surgery. However, a major multicentre and high quality randomised, controlled trial is required to validate these findings. J. Surg. Oncol. 2012; 106:783–795. © 2012 Wiley Periodicals, Inc.  相似文献   
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