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991.
Hiccup is a forceful, involuntary inspiration commonly experienced by fetuses, children and adults. Its purpose is unknown and its pathophysiology still poorly understood. Short hiccup bouts are mostly associated with gastric distention or alcohol intake, resolve spontaneously or with simple folk remedies and do not require medical attention. In contrast, prolonged hiccup is a rare but disabling condition which can induce depression, weight loss and sleep deprivation. A wide variety of pathological conditions can cause chronic hiccup: myocardial infarction, brain tumour, renal failure, prostate cancer, abdominal surgery etc. Detailed medical history and physical examinations will often guide diagnostic investigations (abdominal ultrasound, chest or brain CT scan...). Gastric and duodenal ulcers, gastritis, oesophageal reflux and oesophagitis are commonly observed in chronic hiccup patients and upper gastrointestinal investigations (endoscopy, pH monitoring and manometry) should be included in the diagnostic evaluation systematically. Etiological treatment is not always available and chronic hiccup treatment has classically relied on metoclopramide and chlorpromazine. Recently, baclofen (LIORESAL) has emerged as a safe and often effective treatment.  相似文献   
992.
993.
This work presents a theoretical and experimental study of the biodiesel (ethyl ester from a waste vegetable oil) performance in a flame tube furnace. The heat transfer rate was analysed in several sections along the furnace and the performance of the biodiesel was compared to that of diesel oil. The flow of heat from the burn of each fuel in the direction of the walls of the combustion chamber was evaluated under the same fuel injection pressure. The peak of the heat transfer occurred around 0.45 m far from the fuel injection nozzle in a 0.305 m inner diameter combustion chamber. The diesel oil showed a higher heat transfer rate in most parts exposed to the flame. In the region where the body of the flame is not present, the heat transfer of biodiesel becomes higher.  相似文献   
994.
995.
996.
The present study aimed to evaluate the effect of crude protein degradability and corn processing on lactation performance, milk protein composition, milk ethanol stability (MES), heat coagulation time (HCT) at 140°C, and the efficiency of N utilization for dairy cows. Twenty Holstein cows with an average of 162 ± 70 d in milk, 666 ± 7 kg of body weight, and 36 ± 7.8 kg/d of milk yield (MY) were distributed in a Latin square design with 5 contemporaneous balanced squares, 4 periods of 21 d, and 4 treatments (factorial arrangement 2 × 2). Treatment factor 1 was corn processing [ground (GC) or steam-flaked corn (SFC)] and factor 2 was crude protein (CP) degradability (high = 10.7% rumen-degradable protein and 5.1% rumen-undegradable protein; low = 9.5% rumen-degradable protein and 6.3% rumen-undegradable protein; dry matter basis). A significant interaction was observed between CP degradability and corn processing on dry matter intake (DMI). When cows were fed GC with low CP degradability, DMI increased by 1.24 kg/d compared with cows fed GC with high CP degradability; however, CP degradability did not change DMI when cows were fed SFC. Similar interactions were observed for MY, HCT, and lactose content. When cows were fed GC diets, high CP degradability reduced MY by 2.3 kg/d, as well as HCT and lactose content, compared with low CP degradability. However, no effect of CP degradability was observed on those variables when cows were fed SFC diets. The SFC diets increased dry matter and starch total-tract digestibility and reduced β-casein (CN) content (% total milk protein) compared with GC diets. Cows fed low-CP degradability diets had higher glycosylated κ-CN content (% total κ-CN) and MES, as well as milk protein content, 3.5% fat-corrected milk, and efficiency of N for milk production, than cows fed high-CP degradability diets. Therefore, GC and high-CP degradability diets reduced milk production and protein stability. Overall, low CP degradability increased the efficiency of dietary N utilization and MES, probably due to changes in casein micelle composition, as CP degradability or corn processing did not change the milk concentration of ionic calcium. The GC diets increased β-CN content, which could contribute to reducing HTC when cows were fed GC and high-CP degradability diets.  相似文献   
997.
Abstract

Autism Spectrum Disorders (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) are two increasingly prevalent neurodevelopmental disorders. This rise may be associated with a higher dietary intake of n-6 polyunsaturated fatty acids (PUFAs) and lower of n-3 PUFAs. Docosahexaenoic acid (DHA), a key nutritional n-3 PUFA, is crucial for an optimal offspring’s neurodevelopment through the last trimester of pregnancy. Recently, lower DHA levels have been reported in children with ASD and ADHD. The present review summarizes the main research achievements concerning the effect of DHA in children neurodevelopment, in order to elicit its role in the prevention and mitigation of ASD and ADHD. As main finding, a low DHA supply seems to negatively affect childhood neurodevelopment in specific conditions and increase the risk and the severity of ASD or ADHD. Higher DHA status at birth was associated with better childhood neurodevelopmental, but controversial results found in prenatal supplementation raised the hypothesis that the benefits of DHA may be influenced by other factors as socio-economic background and life-style. In conclusion, an optimal DHA provision through maternal diet or breastfeed may promote some neuronal protection in specific offspring’s populations, suggesting that DHA may act as a modifiable risk factor for ASD and ADHD.  相似文献   
998.
The chemical composition and the antioxidant potential of three species of wild mushrooms from Northeastern Portugal, namely Agaricus albertii, Agaricus urinascens var. excellens, and Pleurotus eryngii, were compared. Standard procedures were followed in the nutritional value evaluation, while chromatographic procedures were used to analyze free sugars, fatty acids, tocopherols, phenolic compounds, and organic acids. To assess the antioxidant potential, reducing power, radical-scavenging activity, and lipid peroxidation inhibition were evaluated. P. eryngii revealed the highest levels of macronutrients, except proteins, as also the highest sugars, tocopherols, and monounsaturated fatty acids contents. A. albertii and A. urinascens var. excellens showed similar macronutrients composition. However, A. albertii revealed the highest content in PUFA and phenolic compounds. P. eryngii revealed the highest reducing power and radical-scavenging activity and A. albertii the highest lipid peroxidation inhibition. This study provides a detailed chemical characterization and antioxidant potential evaluation of three species of wild mushrooms from Portugal not yet previously reported. Thus, this work intended to contribute to the increase of information concerning species of edible mushrooms (directed to the scientific community and general population) as well as contribute to the conservation of these resources as sources of compounds of interest.  相似文献   
999.
This paper describes the models of a wind power system, such as the turbine, generator, power electronics converters and controllers, with the aim to control the generation of wind power in order to maximize the generated power with the lowest possible impact in the grid voltage and frequency during normal operation and under the occurrence of faults. The presented work considers a wind power system equipped with the doubly-fed induction generator and a vector-controlled converter connected between the rotor and the grid. The paper presents comparative results between proportional-integral controllers and neural networks based controllers, showing that better dynamic characteristics can be obtained using neural networks based controllers.  相似文献   
1000.
Bacteria of the genus Pseudomonas have been associated with the spoilage of raw milk and dairy products due to the production of thermostable proteolytic enzymes. The apr gene encodes for alkaline metalloprotease in Pseudomonas and other related bacteria. Its presence in psychrotrophic proteolytic bacteria isolated from raw milk collected from cooling tanks was verified. A polymerase chain reaction (PCR) technique was used with degenerate primers. Total DNA from 112 isolates was pooled in different groups and then used as template for the amplification reactions. Controls consisted of DNA extracted from 26 cultures. An expected DNA fragment of 194 bp was detected in groups that contained bacteria identified as Pseudomonas. The PCR product was observed only when DNA from control cultures of Pseudomonas aeruginosa, Pseudomonas fluorescens, Serratia marcescens and Aeromonas hydrophila were used. A detection limit assay indicated that the apr gene could be directly amplified from pasteurized milk inoculated with 10(8) CFU/ml of P. fluorescens. With this method it was possible to detect proteolytic bacteria at 10(5) CFU/ml in reconstituted skim milk powder if cells were recovered for DNA extraction before amplification.  相似文献   
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