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991.
992.
Summary. The complete nucleotide sequence of isolates of Cucumber vein yellowing virus (CVYV) has been determined. The viral genome comprises 9734 nucleotides, excluding a 3′-terminal poly(A) sequence. The genome of CVYV has a 5′-non coding and a 3′ non coding region of respectively 67 and 240 nucleotides. The RNA of CVYV encodes a single polyprotein of 3148 amino acid residues and has a deduced genome organization and motifs typical for a member of the family Potyviridae. However, CVYV is atypical because it lacks a coding sequence region for the putative helper-component as well as conserved helper-component-proteinase motifs which may account for its vector relations. All the present coding regions were compared to those from several members of the Potyviridae family. CVYV is most closely related to Sweetpotato mild mottle virus confirming its assignation to the genus Ipomovirus, despite similarities with tritimoviruses.  相似文献   
993.
OBJECTIVE: The prevalence of malnutrition is high in patients with head and neck cancer due to tumor location and coadjuvant treatment. We studied changes in resting energy expenditure (REE) during treatment with chemoradiotherapy and compared the measured REE by indirect calorimetry (IC) with the value estimated by the Harris-Benedict (HB) formula. METHODS: Eighteen patients with head and neck cancer (15 men and 3 women, mean age 57 +/- 10.7 y, age range 30-71 y) entered the study. All patients were treated with radiotherapy (70.8 +/- 1 Gy, range 70-72) and received 37.4 +/- 3.5 fractions (range 32-42) and concurrent chemotherapy with cisplatinum (absolute doses of 400 to 1000 mg). Nutrition assessment included anthropometry (body mass index, triceps skinfold thickness, subscapular skinfold thickness, midarm circumference, and midarm muscle circumference) and tetrapolar bioimpedance (Holtain BC). The IC (kcal/24 h; Deltatrac II MBM-200) was performed after an overnight fast. Measurements were done before treatment, at weeks 2, 4, and 6 of treatment, at the end of treatment, and 2 wk after treatment. RESULTS: Body mass index decreased during treatment from 24.7 +/- 4.4 kg/m(2) (range 16.9-31.4) to 22.3 +/- 4.2 kg/m(2) (range 15.1-29.6). REE (kcal/24 h) changed significantly during treatment (IC P < 0.05, HB formula P < 0.001). REE measured by IC appeared as a U-shaped curve, but REE estimated by the HB formula decreased during treatment. The HB underestimated REE measurements compared with IC. These differences were statistically significant before treatment, at the end of treatment, and 2 wk after treatment (P < 0.05) and showed a limited clinical agreement with the Bland-Altman method. CONCLUSIONS: REE measured by IC significantly changed during chemoradiotherapy. It was higher before treatment, at the end of treatment, and 2 wk after treatment. The HB formula underestimated REE in these patients. IC is a suitable method for measuring REE in this cohort of patients.  相似文献   
994.
A 6-month intervention trial was conducted among 542 Filipino children aged 4 to 7 years to determine the effect of vitamin A-fortified coconut cooking oil intake on their vitamin A status and to identify factors that influence this. Children were randomly assigned to the Experimental group, with vitamin A-fortified cooking oil ration; to Control-1 group with unfortified cooking oil ration; and to Control-2 group without cooking oil ration. In all groups, children's serum retinol concentration improved. Relative change in serum retinol concentration was significantly higher among the Experimental group, with one-third of total vitamin A intake coming from vitamin A-fortified cooking oil intake, than in the Control groups, with more than half of intake from other vitamin A-rich foods. Determinants of post-intervention serum retinol concentration included baseline serum retinol concentration, caregiver's education, receipt of high-dose vitamin A capsule, interaction between consumption of vitamin A-fortified cooking oil and of other vitamin A-rich foods, and between households purchasing cooking oil and food expenditure. Intake of vitamin A-fortified cooking oil combined with vitamin A-rich foods was necessary to increase serum retinol concentration. It is recommended to vigorously promote the consumption of vitamin A-fortified cooking oil together with other vitamin A-rich sources to sustain the prevention and control of vitamin A deficiency.  相似文献   
995.
West Nile virus has been isolated for the first time in Mexico, from a sick person and from mosquitoes (Culex quinquefasciatus). Partial sequencing and analysis of the 2 isolates indicate that they are genetically similar to other recent isolates from northern Mexico and the western United States.  相似文献   
996.
To find new compounds with potential neuroprotective activity, we have designed, synthesized, and characterized a series of neural nitric oxide synthase (nNOS) inhibitors with a kynurenamine structure. Among them, N-[3-(2-amino-5-methoxyphenyl)-3-oxopropyl]acetamide is the main melatonin metabolite in the brain and shows the highest activity in the series, with an inhibition percentage of 65% at a 1 mM concentration. The structure-activity relationship of the new series partially reflects that of the previously reported 2-acylamido-4-(2-amino-5-methoxyphenyl)-4-oxobutyric acids, endowed with a kynurenine-like structure. Structural comparisons between these new kinurenamine derivatives, kynurenines, and 1-acyl-3-(2-amino-5-methoxyphenyl)-4,5-dihydro-1H-pyrazole derivatives also reported confirm our previous model for the nNOS inhibition.  相似文献   
997.
998.
Anorectal melanoma: report of three cases with extended follow-up   总被引:1,自引:0,他引:1  
Primary anorectal melanoma is rare. There is controversy regarding the best surgical treatment because of its poor prognosis. Three cases with extended follow-up are reported in this article. A 53-year-old woman with rectal bleeding was diagnosed with a melanoma of the rectum and underwent an abdominoperineal resection. The patient died with distant metastases 8 months later. An 80-year-old woman with rectal bleeding was diagnosed with a melanoma of the rectum and underwent a transanal local excision. She remains alive 4 years later but with locally recurrent disease. A 78-year-old man with rectal bleeding was diagnosed with a melanoma of the rectum and underwent an abdominoperineal resection. He died with local and metastatic disease 25 months later. Recent trends favor local excision when technically feasible, although some patients may require an abdominoperineal resection of the rectum, especially for larger tumors.  相似文献   
999.
1000.
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