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91.
Atherosclerosis, which is closely linked to nutritional habits, is a major cause of mortality in Western countries. Most of the previous investigations carried out on health effects of apples have been focused on their capacity to lower lipid concentration as well as on their antioxidant effects. The aim of the present study was to investigate the antiatherosclerotic effects of apple polyphenols and fibers. A crude apple polyphenol extract and low-viscosity apple fibers isolated from cider apples were administered separately or in association with the diet of apo E-deficient mice. After 4 months of supplementation, lipemia and oxidative stress biomarkers were measured and atheroslerotic lesions assessed by histomorphometry. Total plasmatic cholesterol and triacylgycerol levels were not affected by supplementation, and hepatic cholesterol level was lower in the group supplemented with both fibers and polyphenols. Uric acid concentrations and antioxidant capacity (FRAP) in plasma were reduced in all groups supplemented with polyphenols or fibers. The mean lesion area was reduced by 17, 38, and 38%, respectively, for the polyphenol, fiber, and polyphenol + fiber groups. Apple constituents supplied at nutritional doses therefore limit the development of atherosclerotic lesions in the aorta of apo E-deficient mice. On the basis of the results, we hypothesize that apple fibers and polyphenols may play a role in preventing atherosclerosis disease by decreasing uric acid plasma level.  相似文献   
92.
The carbonyl-amine reaction between pyruvic acid and alpha-amino alcohols was monitored by Fourier transform infrared spectroscopy at a temperature range between 20 and 100 degrees C and under acidic and basic conditions. To avoid interference, the reactions were conducted in the absence of solvent using liquid reactants such as methyl pyruvate, pyruvic acid, ethanolamine, and 1-amino-2,3-propanediol. Analysis of the time- and temperature-dependent spectra indicated that under basic conditions and at room temperature, the initial imine formation and its subsequent isomerization through a 1,3-prototropic shift occur very rapidly and the reaction goes to completion within 12 min. Interestingly, the isomerization product of the initial imine is the so-called Schiff base intermediate formed when the corresponding amino acid and the reducing sugar react during a typical Maillard reaction. Furthermore, the detailed studies also indicated that during the first 30 s, the rate of formation of the initial imine was faster than the rate of its isomerization; however, after 60 s, its rate of isomerization becomes faster than the rate of its formation. The data also indicated that under acidic conditions, this isomerization was prevented from occurring and the reaction was terminated at the initial imine formation stage. In addition, temperature-dependent spectra indicated that the isomerization of the Schiff's base into eneaminol can be achieved at or above 60 degrees C and its subsequent rearrangement into Amadori product can be attained at temperatures above 80 degrees C even under basic conditions, thus providing a novel route to Maillard reaction products starting from a keto acid and an amino alcohol. This observation was also confirmed through identification of the common Amadori product in both keto acid/amino alcohol and sugar/amino acid mixtures, by the application of tandem mass spectrometry and chemical ionization techniques.  相似文献   
93.
X-ray absorption spectroscopy (XAS) of Fe(2+) in Fe(2)SiO(4) liquid at 1575 kelvin and 10(-4) gigapascal (1 bar) shows that the Fe(2+) -O bond length is 1.98 +/- 0.02 angstroms compared with approximately 2.22 angstroms in crystalline Fe(2)SiO(4) (fayalite) at the melting point (1478 kelvin), which indicates a decrease in average Fe(2+) coordination number from six in fayalite to four in the liquid. Anharmonicity in the liquid was accounted for using a data analysis procedure. This reduction in coordination number is similar to that observed on the melting of certain ionic salts. These results are used to develop a model of the medium-range structural environment of Fe(2+) in olivine-composition melts, which helps explain some of the properties of Fe(2)SiO(4) liquid, including density, viscosity, and the partitioning of iron and nickel between silicate melts and crystalline olivines. Some of the implications of this model for silicate melts in the Earth's crust and mantle are discussed.  相似文献   
94.
H Moltz  R Levin  M Leon 《Science (New York, N.Y.)》1969,163(871):1083-1084
Postpartum female rats deprived of suckling stimulation while being kept continuously with pups nonetheless suspended ovarian cyclicity for an average of 16 days and responded to uterine trauma by forming deciduomata. These results show that the extramammary stimulation afforded by young is alone capable of sustaining prolactin output from the adenohypophysis of the postpartum rat.  相似文献   
95.
96.
Although cryptosporidiosis is frequently diagnosed in the U.S., there has been very little assessment of obstetrician–gynaecologist knowledge about this disease. In 2010, we surveyed U.S. obstetricians about the diagnosis, treatment and epidemiology of cryptosporidiosis. Data were examined through univariable analysis and multivariable regression models. Of 1000 obstetrician–gynaecologists surveyed, 431 (43.1%) responded. Only 44.4% of respondents correctly identified that prolonged, intermittent diarrhoea would lead them to consider cryptosporidiosis in a differential diagnosis. Routine ova and parasites (O&P) testing was incorrectly chosen to identify Cryptosporidium in stool by 30.4% of respondents. Questions about nitazoxanide, the only drug approved by the U.S. Food & Drug Administration (FDA) for treatment of cryptosporidiosis, were the most frequently missed questions. Only 9.0% of respondents correctly classified nitazoxanide as an FDA pregnancy Category B drug, and only 5.6% of respondents correctly indicated that FDA approved nitazoxanide for immunocompetent patients aged ≥1 years. Regarding prevention‐ and control‐related knowledge, only 14.1% of respondents correctly indicated that alcohol‐based hand sanitizers were not effective at inactivating Cryptosporidium spp., and <10% correctly indicated that cryptosporidiosis is a reportable disease in their state of practice. Multivariable analysis found that ≥19 years in practice was positively associated with O&P diagnostic testing knowledge, while rural and urban non‐inner city practice location, compared with suburban practice location, was positively associated with nitazoxanide knowledge. The low level of knowledge among obstetrician–gynaecologists about cryptosporidiosis indicates a need to develop resources for physicians about all aspects of cryptosporidiosis, particularly on diagnosis, treatment and prevention strategies.  相似文献   
97.
A 7-year-old castrated border collie dog was anesthetised for surgical resection of a hippocampal mass. Anesthesia was maintained using a previously unreported TIVA protocol for craniectomy consisting of alfaxalone and remifentanil. Recovery was uneventful, and the patient was discharged from hospital. We describe the anesthetic management of this case.  相似文献   
98.
The aim of the present study was to evaluate anti-Neospora caninum antibodies and the vertical transmission rate in naturally infected pregnant zebu beef cows (Bos indicus) reared on pasture. The present study began with 200 cows from four farms (50 cows from each farm), and these animals were submitted to timed artificial insemination (TAI). After ultrasonography, 76 pregnant cows were selected, 22, 15, 22, and 17, respectively, from farms 1, 2, 3, and 4. Blood samples were taken from cows thrice during the first, second, and third trimester of gestation, and a blood sample was collected from 31 calves before colostrum milking. From 76 cows 23 (30.3%) had anti-N. caninum antibodies detected by indirect ELISA (Idexx), and 53 (69.7%) did not. Sixty-four cows that initiated the experiment were negative to N. caninum and 11 became positive either during the second or third trimester of gestation, this mean an infection incidence of 17.2% (11/64). OD for ELISA was higher (OD = 2.08) during the second and third (OD = 2.10) trimesters of pregnancy when compared with the first (OD = 1.81), however, there were no statistical differences (P = 0.45). The vertical transmission was calculated to be 29.0% (9/31), and the risk of vertical transmission of N. caninum in seropositive dams was 26.25 times higher than seronegative animals (OR = 26.25, 2.38 < OR < 289, P = 0.007). In conclusion, the rate of vertical transmission of N. caninum in pregnant zebu beef cows was 29%, and the risk was 26.25 higher in seropositive dams relative to than seronegative animals.  相似文献   
99.
The performance of micro flood irrigation (MFI) under different inflow rates was evaluated on 90 m closed ended furrows in the South African Tukulu soil. A single irrigation was used to characterise the surface and subsurface soil water distribution from the 20, 40, 80 and 160 L/min inflow rates treatments. Neutron access tubes were installed to a depth of 1 m at every 10 m distance interval starting at 5 m from the furrow inlet. Soil water content measurements were taken using the WaterMan neutron water meter. The HYDRUS-2D software was also used to provide insight on irrigated furrows soil water content and subsurface water distribution. The 20 L/min produced a stream flow that could advance up to the 60 m furrow distance. The stream flow from the rest of the inflow rates were able to reach the furrow end with the 180 L/min recording the fastest advance time of 23 min. The 20 L/min and 40 L/min had recession period of less than 7 min while the 80 L/rain and 160 L/min lasted more than an hour. Distribution uniformity (DU) at longer furrow distances was the highest from the 80 L/min and 160 L/min with the 20 L/min and 40 L/min recorded similar performances at shorter distances. The 40 L/rain was one of the smaller inflow rates that recorded the highest DU of 0.96 for the generated average infiltrated depth of the 30 m long furrow and therefore should be adopted for furrow distances of less than 60 m on the Tukulu soil.  相似文献   
100.
The ide Leuciscus idus (Linnaeus 1758) belongs to autochthonous, less frequent and vulnerable fish species in the frame of ichthyofauna of the Czech Republic. It was the reason for testing the possibility of captive breeding and production of fry in a controlled environment. The goal of this paper was to find the optimal transfer time of ide larvae from live food (Artemia salina nauplii) to dry starter feed providing good survival and growth. At the end of the experiment, high values of cumulative survival (in percentages) and individual weight (in milligrammes) were found for ide fry in groups D (90.6%, 178.6 mg; 15 days A. salina + 10 days starter feed), A (89.9%, 169.9 mg; A. salina only) and C (88.6%, 160.4 mg; 10 days A. salina + 15 days starter feed). Significantly lower values of the given parameters were found in group B (57.1%, 92.6 mg; 5 days A. salina + 20 days starter feed), and the lowest ones were in group E (29.8%, 75.6 mg; starter feed only). Mean values of the level of ontogenesis at the end of the experiment in fry of A–E groups were analogous to length and weight growth. Groups D, C and A consisted of juveniles only (J1, J2), and groups B and E consisted of larvae and juveniles (L4, L5, L6, J1, J2). Condition and production parameters [Fulton’s coefficient of condition (FWC), total length (TL), weight (w), specific growth rate (SGR), food conversion ratio (FCR), cumulative survival] and relationships between basic lengths TL, fork length (FL) and standard length (SL) were evaluated.  相似文献   
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