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31.
The bioavailability of calcium (Ca) was assessed in 11 foodstuffs of plant or animal origin using rat feeding experiments and the criteria used for assessing the bioavailability were femur Ca and calcium efficiency. The bioavailability of Ca was found to be highest in fishes (Melouha) and cheeses (Mesh) fermented under local processing techniques. Germination of faba beans also enhanced the bioavailability of calcium to a mean value quite comparable to those of some dairy products, such as cottage cheese. The present study clearly demonstrates that the processes of fermentation and germination of selected foods are associated with an enhancement in the bioavailability of calcium. It is suggested that the breakdown of complex proteins under the fermentation or germination process is the underlying mechanism of action.  相似文献   
32.
This study aimed at evaluation of validity and reliability of dipstick haematuria and proteinuria in screening school children for Schistosoma haematobium infection. It included a random sample of 400 school children aged 6-15 years in rural area of Fayoum Governorate, upper Egypt. Urine samples of the studied children were tested parasitologically by urine filtration technique as a reference test and semiquantitatively for haematuria and proteinuria using urine reagent strips as screening tests. Results of the study revealed that haematuria was a better indicator for Schistosoma haematobium infection than proteinuria, as it was more sensitive (85.5% 73.4%, respectively), specific (94.4% 82.9%, respectively) and reliable (kappa=92% 80%, respectively). Moreover, it had stronger relationship with intensity of infection (r=0.88 & 0.67, respectively). A combination of different grades of haematuria and proteinuria did not significantly increase either sensitivity or specificity. Dipstick haematuria could be a valuable technique in screening rural Egyptian school children who are at risk of urinary schistosmiasis.  相似文献   
33.
Purpose: Both ondansetron and cyclophosphamide are thought to be metabolized by hepatic microsomal processes. The purpose of this study was to evaluate the potential pharmacokinetic interactions between ondansetron and high-dose alkylating agent chemotherapy. Methods: A total of 54 breast cancer patients receiving high-dose cyclophosphamide, cisplatin and carmustine were treated prospectively in four sequential cohorts. Cohorts I and II received continuous infusions of both ondansetron and prochlorperazine, and cohorts III and IV received a continuous infusion of ondansetron alone at the same doses. All patients received lorazepam every 4 h. A group of 75 matched historical controls had received a continuous infusion of prochlorperazine with lorazepam. Pharmacokinetic monitoring of each drug used in the high-dose chemotherapy regimen was conducted. Results: Median AUCs of cyclophosphamide in patients receiving ondansetron (73.6 mg/ml · min) were lower than those of the control patients (88.3 mg/ml · min, n = 75, P = 0.0004), but the median cisplatin AUC was approximately 10% higher and no difference in the disposition of carmustine was demonstrated. Patients treated with ondansetron displayed a higher frequency of headaches than the controls. The frequency of achieving complete emetic control was greater in the ondansetron + prochlorperazine groups compared to the ondansetron alone groups and was greater in both these groups than in the prochlorperazine alone group on the first day of therapy only. Conclusion: Ondansetron altered the systemic exposure to cyclophosphamide when these agents were administered concomitantly. Ondansetron did not substantially improve overall emetic control when used alone but may improve control in combination with prochlorperazine. Future randomized studies are needed to delineate the effect of ondansetron on the disposition of the active cyclophosphamide metabolites so that clinical implications can be addressed. Received: 28 October 1997 / Accepted: 9 March 1998  相似文献   
34.
OBJECT: Glioblastoma multiforme (GBM) invasiveness is a complex process that involves recognition and attachment of GBM cells to particular extracellular matrix (ECM) molecules before migrating into proteolytically modified matrix and inducing angiogenesis. The CD44 molecule, which is a transmembrane adhesion molecule found on a wide variety of cells including GBM, has been suggested as the principal mediator of migration and invasion. The aim of the present study was to demonstrate whether an antibody specific to the standard form of CD44 (CD44s, 85-90 kD) might prevent invasion and thus disrupt progression of C6 GBM in vivo. METHODS: Immunostaining demonstrated homogeneous expression of CD44s on the surface of C6 GBM cells and tumors. Flow cytometric analysis demonstrated binding saturation of anti-CD44s monoclonal antibody (mAb) to the receptor at 1 microg/5 x 10(5) cells. Blocking of CD44s in vitro resulted in a dose-dependent progressive (up to 94+/-2.7%; mean +/- standard deviation [SD]) detachment of C6 cells from ECM-coated culture. Blocking of CD44s in vivo resulted in significantly reduced C6 brain tumors (3.6+/-0.4% [SD])--measured as the quotient: tumor surface (mm2)/brain surface (mm2) x 100--compared with untreated (19.9+/-0.9%) or sham-treated (19.2+/-1.1 to 19.3+/-2.5% [SD]) rats. Disruption of C6 GBM progression correlated with an improved food intake; treated rats were significantly less cachectic (166.6+/-16.4 g [SD]) than those that were untreated (83+/-2.7 g [SD]) or sham-treated (83.4+/-1.1 to 83+/-2.2 g [SD]) rats. CONCLUSIONS: The authors conclude that CD44s-targeted treatment with specific mAb may represent an effective means for preventing progression of highly invasive GBMs.  相似文献   
35.
AIMS: To investigate glucose and leucine kinetics in association with metabolic and endocrine investigations in children with ketotic hypoglycaemia (KH) in order to elucidate the underlying pathophysiology. METHODS: Prospective interventional study using stable isotope tracer in nine children (mean age 4.23 years, range 0.9-9.8 years; seven males) with KH and 11 controls (mean age 4.57 years, range 0.16-12.3 years; four males). RESULTS: Plasma insulin levels were significantly lower in KH compared to subjects in the non-KH group. Plasma ketone body levels were significantly higher in KH than in non-KH. Basal metabolic rate was significantly higher in subjects with KH (45.48+/-7.41 v 31.81+/-6.72 kcal/kg/day) but the respiratory quotients were similar in both groups (KH v non-KH, 0.84+/-0.05 v 0.8+/-0.04. Leucine oxidation rates were significantly lower in children with KH (12.25+/-6.25 v 31.96+/-8.59 micromol/kg/h). Hepatic glucose production rates were also significantly lower in KH (3.84+/-0.46 v 6.6+/-0.59 mg/kg/min). CONCLUSIONS: KH is caused by a failure to sustain hepatic glucose production rather than by increased glucose oxidation rates. Energy demand is significantly increased, whereas leucine oxidation is reduced.  相似文献   
36.
A crucial factor in the efficient design of concrete sustainable buildings is the compressive strength (Cs) of eco-friendly concrete. In this work, a hybrid model of Gradient Boosting Regression Tree (GBRT) with grid search cross-validation (GridSearchCV) optimization technique was used to predict the compressive strength, which allowed us to increase the precision of the prediction models. In addition, to build the proposed models, 164 experiments on eco-friendly concrete compressive strength were gathered for previous researches. The dataset included the water/binder ratio (W/B), curing time (age), the recycled aggregate percentage from the total aggregate in the mixture (RA%), ground granulated blast-furnace slag (GGBFS) material percentage from the total binder used in the mixture (GGBFS%), and superplasticizer (kg). The root mean square error (RMSE) and coefficient of determination (R2) between the observed and forecast strengths were used to evaluate the accuracy of the predictive models. The obtained results indicated that—when compared to the default GBRT model—the GridSearchCV approach can capture more hyperparameters for the GBRT prediction model. Furthermore, the robustness and generalization of the GSC-GBRT model produced notable results, with RMSE and R2 values (for the testing phase) of 2.3214 and 0.9612, respectively. The outcomes proved that the suggested GSC-GBRT model is advantageous. Additionally, the significance and contribution of the input factors that affect the compressive strength were explained using the Shapley additive explanation (SHAP) approach.  相似文献   
37.
African swine fever virus (ASFV) is the causative agent of African swine fever (ASF), resulting in up to 100% mortality in pigs. Although endemic in most sub-Saharan African countries, where all known ASFV genotypes have been reported, the disease has caused pandemics of significant economic impact in Eurasia, and no vaccines or therapeutics are available to date. In endeavors to develop live-attenuated vaccines against ASF, deletions of several of the ~170 ASFV genes have shown contrasting results depending on the genotype of the investigated ASFV. Here, we report the in vivo outcome of a single deletion of the A238L (5EL) gene and double deletions of A238L (5EL) and EP402R (CD2v) genes from the genome of a highly virulent genotype IX ASFV isolate. Domestic pigs were intramuscularly inoculated with (i) ASFV-Ke-ΔA238L to assess the safety of A238L deletion and (ii) ASFV-Ke-ΔEP402RΔA238L to investigate protection against challenge with the virulent wildtype ASFV-Ke virus. While A238L (5EL) gene deletion did not yield complete attenuation, co-deletion of A238L (5EL) and EP402R (CD2v) improved the safety profile of the single deletions, eliciting both humoral and cellular immune responses and conferred partial protection against challenge with the virulent wildtype ASFV-Ke virus.  相似文献   
38.
We describe the characterization of an African swine fever genotype IX virus (ASFV-Kenya-IX-1033), which was isolated from a domestic pig in western Kenya during a reported outbreak. This includes the efficiency of virus replication and in vivo virulence, together with genome stability and virulence, following passage in blood macrophages and in a wild boar lung cell line (WSL). The ASFV-Kenya-IX-1033 stock retained its ability to replicate in primary macrophages and retained virulence in vivo, following more than 20 passages in a WSL. At the whole genome level, a few single-nucleotide differences were observed between the macrophage and WSL-propagated viruses. Thus, we propose that the WSL is suitable for the production of live-attenuated ASFV vaccine candidates based on the modification of this wild-type isolate. The genome sequences for ASFV-Kenya-IX-1033 propagated in macrophages and in WSL cells were submitted to GenBank, and a challenge model based on the isolate was developed. This will aid the development of vaccines against the genotype IX ASFV circulating in eastern and central Africa.  相似文献   
39.
Congenital heart surgery (CHS) is technically demanding, and its training is extremely complex and challenging. Training of the surgeon’s technical skills has relied on a preceptorship format in which the trainees are gradually exposed to patients in the operating room under the close tutelage of senior staff surgeons. Training in the operating room is an inefficient process and the concept of a learning curve is no longer acceptable in terms of patient outcomes. The benefits of surgical simulation in training of congenital heart surgeons are well known and appreciated. However, adequate surgical simulation models and equipment for training have been scarce until the recent development of three-dimensionally (3D) printed models. Using comprehensive 3D printing and silicone-molding techniques, realistic simulation training models for most congenital heart surgical procedures have been produced. Newly developed silicone-molded models allow efficient CHS training in a stress-free environment with instantaneous feedback from the proctors and avoids risk to patients. The time has arrived when all congenital heart surgeons should consider surgical simulation training before progressing to real-life operating in a similar fashion to the aviation industry where all pilots are required to complete simulation training before flying a real aircraft. It is argued here that simulation training is not an option anymore but should be a mandatory component of CHS training.  相似文献   
40.
An efficient electrochemical sensor containing polyaniline/cerium oxide (PANI/CeO2) nanocomposites for the detection of hydrogen peroxide has been fabricated using the traditional in situ oxidative polymerization process. PANI/CeO2 nanocomposite-based modified glassy carbon electrodes were utilized as an electrochemical sensor for the detection of hydrogen peroxide. Before the fabrication, CeO2 was prepared by a hydrothermal method, and common techniques confirmed its structure. PANI/CeO2 nanocomposites were prepared by adding variable loadings of the pre-prepared CeO2 nanoparticles (weight%) inside the polymer host matrix. All the nanocomposites were characterized to determine their chemical structures and suitability for electrode materials. The electrode detection limit, sensitivity, and effect of pH on the sensor performance were investigated using different electrochemical methods, including cyclic voltammetry, electrochemical impedance spectroscopy, and linear sweep voltammetry. The results indicated that the sensing abilities of the synthesized PANI/CeO2(10) nanocomposite-modified GCE presented good electrocatalytic oxidation properties towards H2O2 with an enhanced low limit of detection and good repeatability. The fabricated electrode sensor was successfully used to detect H2O2 in real samples.

An efficient electrochemical sensor containing (PANI/CeO2) for the detection of hydrogen peroxide has been fabricated using the in situ oxidative polymerization. The fabricated electrode sensor was successfully used to detect H2O2 in real samples.  相似文献   
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