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21.
The potential of by-products generated during extra-virgin olive oil (EVOO) filtration as a natural source of phenolic compounds (with demonstrated bioactivity) has been evaluated using pressurized liquid extraction (PLE) and considering mixtures of two GRAS (generally recognized as safe) solvents (ethanol and water) at temperatures ranging from 40 to 175 °C. The extracts were characterized by high-performance liquid chromatography (HPLC) coupled to diode array detection (DAD) and electrospray time-of-flight mass spectrometry (HPLC-DAD-ESI-TOF/MS) to determine the phenolic-composition of the filter cake. The best isolation procedure to extract the phenolic fraction from the filter cake was accomplished using ethanol and water (50:50, v/v) at 120 °C. The main phenolic compounds identified in the samples were characterized as phenolic alcohols or derivatives (hydroxytyrosol and its oxidation product), secoiridoids (decarboxymethylated and hydroxylated forms of oleuropein and ligstroside aglycones), flavones (luteolin and apigenin) and elenolic acid derivatives. The PLE extraction process can be applied to produce enriched extracts with applications as bioactive food ingredients, as well as nutraceuticals.  相似文献   
22.
OBJECTIVE: To analyse plasma HIV-1 RNA levels as a marker of clinical stability and survival in a cohort of HIV-infected patients whose time of seroconversion is unknown. DESIGN: Retrospective cohort study. SETTING: Retrovirology laboratory and AIDS Unit in a teaching hospital. PATIENTS: A total of 916 samples from 302 patients, most on antiretroviral therapy, were analysed. Mean initial CD4 cell counts and HIV-1 RNA were 299 x 10(6)/l (range: 0-1600) and 134,261 copies/ml (range: < 200-4,300,000), respectively. Sixty-six cases had been diagnosed previously with AIDS. METHODS: Analysis of progression to AIDS and survival, according to initial and longitudinal viral load (VL) and CD4 cell count measurements was performed by Kaplan-Meier test. Relative risks were calculated by Cox's proportional hazards model. RESULTS: During a mean follow-up of 444 +/- 309 days, 29 patients developed AIDS and 21 died. Relative risk (RR) of progression related to the group with VL < 35,000 was: 10.4 when CD4 > or = 250 x 10(6)/l and VL > or = 35,000 (P = 0.001); and 45.3 when CD4 < 250 x 10(6)/l and VL > or = 35,000 (P < 0.0001). Cumulative probability of progression was: 0%, 0% and 12.3%, at the first, second and third year respectively, for patients with all their sequential VL determinations < 60,000; and 13.3%, 34.7% and 79.3% for patients who did not maintain VL values always < 60,000 (RR = 23; P < 0.0001). The minimum value of VL that reached statistical significance for the survival analysis was 100,000 copies/ml (P < 0.0001). CONCLUSIONS: VL > or = or < 35,000 is a better discriminant for progression than a CD4 cell count > or = or < 250 x 10(6)/l. Sequential VL determinations < 60,000 are associated with a better prognosis.  相似文献   
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OBJECTIVE: To assess the longterm survival of patients with giant cell arteritis (GCA) in a well defined area in Northwestern Spain. METHODS: A followup study of consecutive biopsy proven patients with GCA diagnosed in Lugo, Spain January 1, 1982-March 31, 1996 was performed. Patients were followed from time of diagnosis until either their death or October 1, 1996. Time and cause of death were reviewed. Statistical methods included standardized mortality ratio (SMR), and Kaplan-Meier product-limit survival analysis. Cox proportional hazard models were used to identify clinical features and laboratory findings associated with survival. RESULTS: By October 1, 1996, full information about 109 biopsy proven patients with GCA (59 men/50 women) was available. The mean age +/- SD at the time of diagnosis was 73.9 +/- 7.3 years for women and 74.1 +/- 5.8 for men (p = NS). After a median followup of 54 months, 22 patients (20.2%) had died. Three died within the first month after diagnosis due to either vascular complications related to GCA or therapy complications. Apart from a history of severe underlying diseases (comorbid condition unrelated to GCA), neither sex nor any clinical features of GCA were significantly associated with an increase in mortality. As in the general population of the same age in Lugo, the majority of deaths were due to cardiovascular and cerebrovascular complications. SMR was 0.80 (95% CI 0.47-1.13). One, 2, 5, and 10 year survival rates were 95, 91, 81, and 62%, respectively. Hazard function was 1.8% at Day 30 after diagnosis and remained low until the end of the first year of treatment. Thereafter, mortality increased slightly. As this function was constant, we applied an exponential model. The estimated risk of death with this model was 5.3% per year. CONCLUSION: Longterm mortality of GCA in our area is low. However, it may be possible to further lower the mortality rate through early diagnosis and careful followup.  相似文献   
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The aim of this study was to assess the relationship between bulky DNA adducts in white blood cells (WBC) and lifestyle factors in a sample from the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC). 296 subjects aged between 35 and 64 years, from five regions, were included. Food intake was estimated with a computerized version of dietary history questionnaire. Daily intake of polycyclic aromatic hydrocarbons (PAH) was estimated using a database with information on food content of potential carcinogens. Data on lifestyle and health factors were collected and DNA adducts measured using the nuclease P1 32P-postlabelling technique. Geometric means of adducts were similar for men and women (4.11/109 and 3.94/109 nucleotides, respectively). Highest levels of adduct were observed in non-smokers and non-occupationally exposed. Meat intake, oils and fats were associated with higher levels of adducts, but all non-statistically significant. Higher intakes of calcium, sodium and phosphorus were associated with lower adducts levels. Summarising, our study shows that bulky adducts measured by 32P-postlabelling in DNA from WBC do not correlate with the usual diet of healthy Spanish adults. Although it has been proposed that diet be the main source of PAH in nonsmokers without occupational exposure, DNA adducts do not seem to be suitable biomarkers of dietary PAH in general population.  相似文献   
27.
The lack of availability of pediatric donors for liver transplant has resulted in a high mortality rate among children awaiting transplantation, especially in patients weighing less than 10 kg. Knowledge of techniques of liver reduction allows liver transplantation in low-weight children with an adult liver graft, although with increased risk. The authors studied 70 pediatric liver transplants, 14.3% of whom received a reduced-size organ. Maximal difference between donor and recipient weight was 7.7. Segments II, III and IV (right hepatectomy) were transplanted in eight cases while segments II and III were transplanted in two cases. Transfusional requirements during the 48 hour postoperative period were not significantly different between patients with reduced-size liver and patients who received the full-size organ. There was not morbi-mortality secondary to surgical technique in reduced liver transplant group of patients.  相似文献   
28.
The interplay between genetic and epigenetic factors plays a central role in mammalian embryo production strategies that superimpose ex vivo or in vivo manipulations upon strain background characteristics. In this study, we examined the relationship between genetic background and the phenotypic properties of mouse metaphase-II (M-II) oocytes that were matured under in vivo (IVO) or in vitro conditions, either in a basal (IVM) or a supplemented (IVM + ) medium. Differences existed amongst inbred (C57BL/6), outbred (CF-1, Black Swiss, NU/NU) and hybrid lines (B6D2F1) induced to superovulate with regard to cytoplasmic microtubule organizing center (MTOC) number but not spindle size or shape, except for larger and asymmetrical spindles in Black Swiss oocytes. When oocytes were matured in culture, meiotic spindle and cytoplasmic phenotypic properties of M-II oocytes were affected relative to in vivo conditions and between strains. Specifically, measures of meiotic spindle size, shape, polar pericentrin distribution and cytoplasmic MTOC number all revealed characteristic variations. Interestingly, the overall reduction in cytoplasmic MTOC number noted upon IVM was concomitant with an overall increase in spindle and polar body size. Maturation under IVM + conditions resulted in a further decrease in cytoplasmic MTOC number, but spindle and polar body characteristics were intermediate between IVO and IVM. How these oocyte phenotypic properties of maternal origin may be linked to predictive assessments of fecundity remains to be established.  相似文献   
29.
We present a beam-shaping technique for two-photon excitation (TPE) fluorescence microscopy. We show that by inserting a properly designed three-ring pupil filter in the illumination beam of the microscope, the effective optical sectioning capacity of such a system improves so that the point spread function gets a quasi-spherical shape. Such an improvement, which allows the acquisition of 3D images with isotropic quality, is obtained at the expense of only a small increase of the overall energy in the axial sidelobes. The performance of this technique is illustrated with a scanning TPE microscopy experiment in which the image of small beads is obtained. We demonstrate an effective narrowing of 12.5% in the axial extent of the point spread function, while keeping the 82% of the spot-fluorescence efficiency.  相似文献   
30.
The effect of selection for growth rate on the sensory characteristics of rabbit meat was assessed by comparing a selected and a control population of rabbits. Embryos belonging to generation 7th were frozen, thawed and implanted in does in order to produce the control group. The control group was formed from the offspring of the embryos belonging to the 7th generation. Selected animals belonging to 21st generation (S) were compared with animals of the control group (C), both were contemporary. Forty animals per group were slaughtered at 9-weeks-old. The sensory analysis was carried out on samples of the Longissimus dorsi muscle. The parameters evaluated were: intensity of rabbit flavour (IRF), aniseed odour (AO), aniseed flavour (AF), liver flavour (LF), tenderness (T), juiciness (J), fibrousness (F). A Bayesian analysis was performed. The ratio of the selection and control effects was analysed. There was a difference between the selected and control groups for IRF, AO, AF and LF. Conversely, no differences were found in T, J and F between groups. Selected group had 3% and 23% higher values of IRF and LF, respectively, than the control group. A relevant effect of selection on AO and AF appeared (probability of relevance P(r)=1), with lower values for selected animals. There was a difference between male and female groups for IRF, but this was not relevant. No differences between sexes were found for the rest of the characteristics evaluated. Selection for growth rate did not affect the main sensory characteristics of meat, like T and J but, it had a negative effect on some flavour characteristics.  相似文献   
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