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111.
The behaviour of the donor melanoblasts from the leg bud mesoderm of Silver Campine implanted into White Leghorn embryos has been studied. Their schedule of migration from intracoelomic grafts to various parts of hosts is worked out. Different hypotheses for differentiation of grafted spherical melanoblasts in various tissues of hosts have been investigated.  相似文献   
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Levels of luteinizing hormone (LH), estradiol-17 beta and progesterone were determined by specific radioimmunoassays in sera obtained from Beagle bitches during proestrus, estrus and diestrus. Concentrations of LH (expressed as NIH-LH-SI equivalents) were 2.8 plus or minus 0.1 ng/ml in proestrus, 35.5 plus or minus 10.0 ng/ml during early estrus and 2.2 plus or minus 0.1 ng/ml in early diestrus. Peak levels of estradiol-17beta (68.9 plus or minus 11.0 ng/ml) were detected 24 hr prior to the LH peak, declined rapidly and reached basal levels (17.8 plus or minus 6.3 ng/ml) by five days following the LH peak. Levels of progesterone were 1.7 plus or minus 0.3 ng/ml during proestrus, 3.5 plus or minus 0.3 ng/ml during early estrus and 23.3 plus or minus 2.8 ng/ml on day 5 after the LH peak . Progesterone levels remained elevated through day 28 of diestrus and pregnancy. A significant decrease (p smaller than 0.05) in levels of prosgesterone occurred between day 28 of pregnancy and one day prior to shelping (3.3 plus or minus 1.2 ng/ml, with a further decrease on the day of whelping (1.1 plus or minus 0.2 ng/ml). Levels of estradiol-17beta and LH did not change significantly (p smaller than 0.0k) during diestrus or pregnancy.  相似文献   
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Summary F1 plants, monosomic for chromosomes 1A to 7B, from crosses of three lines of Triticum durum var. Khapli with the Chinese series were investigated together with their backcrosses to normal Chinese Spring. The three Khapli lines were designated K1-A, K1-B, and K1-D. Five parameters were analyzed: awn development, glume color, degree of selfing, crossing ability, and seed abortion.Morphological examination of F1 monopentaploid plants revealed that, in the three lines, chromosomes 5A, 1B, 3B, 4B, 5B, and 6B had promotor genes and 2A, 6A, and 2B had inhibitor genes for awn development. Results on glume color suggested the presence of at least three inhibitor genes on 1B, 5B, and 7B, and three promotor genes on 3A, 6A, and 6B chromosomes of Chinese Spring.The first backcross of interspecific hybrids seemed to indicate that some chromosomes (1A, 1B, and 4B) originating from the Khapli lines possessed promotor genes, others (2B and 4A) carried inhibitor genes for seed setting. Similarily, the genetic factor (s) carried by chromosome 5A increased seed abortion whereas those on 2B and 6B reduced it.Self fertility in K1-D hybrids was probably the result of the inhibitor factor (s) on 7A and promotor genes on 3B, 4B, 5B, and 6B chromosomes coming from K1-D.  相似文献   
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In a double-blind crossover trial sodium valproate or placebo was added to the existing anticonvulsant treatment of 20 patients with chronic uncontrolled epilepsy. Sodium valproate 1200 mg/day significantly reduced the frequency of both tonic-clonic and minor seizures in these patients. Only mild and transient side effects occurred (drowsiness, ataxia, and nausea), and these may have been due to the effect of adding sodium valproate to existing phenobarbitone or phenytoin treatment. Further controlled trials are needed to assess more fully the efficacy of this drug in various types of epilepsy.  相似文献   
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ObjectivesTo assess the prevalence of noncommunicable disease (NCD) risk factors among Saudi university employees and their families; to estimate the cardiovascular risk (CVR) amongst the study population in the following 10years.MethodsThe NCD risk factors prevalence was estimated using a cross-sectional approach for a sample of employees and their families aged ≥ 18 years old, in a Saudi university (Riyadh in Kingdom of Saudi Arabia; KSA). WHO STEPwise standardized tools were used to estimate NCD risk factors and the Framingham Coronary Heart Risk Score calculator was used to calculate the CVR.ResultsFive thousand and two hundred subjects were invited, of whom 4,500 participated in the study, providing a response rate of 87%. The mean age of participants was 39.3±13.4 years. The majority of participants reported low fruit/vegetables consumption (88%), and physically inactive (77%). More than two thirds of the cohort was found to be either overweight or obese (72%), where 36% were obese, and 59% had abdominal obesity. Of the total cohort, 22–37% were found to suffer from dyslipidaemia, 22% either diabetes or hypertension, with rather low reported current tobacco use (12%). One quarter of participants was estimated to have >10% risk to develop cardiovascular disease within the following 10-years.ConclusionThe prevalence of NCD risk factors was found to be substantially high among the university employees and their families in this study.  相似文献   
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We previously reported the antifungal properties of a monoterpene phenol “Eugenol” against different Candida strains and have observed that the addition of methyl group to eugenol drastically increased its antimicrobial potency. Based on the results and the importance of medicinal synthetic chemistry, we synthesized eugenol-tosylate and its congeners (E1-E6) and tested their antifungal activity against different clinical fluconazole (FLC)- susceptible and FLC- resistant C. albicans isolates alone and in combination with FLC by determining fractional inhibitory concentration indices (FICIs) and isobolograms calculated from microdilution assays. Minimum inhibitory concentration (MIC) results confirmed that all the tested C. albicans strains were variably susceptible to the semi-synthetic derivatives E1-E6, with MIC values ranging from 1–62 μg/ml. The test compounds in combination with FLC exhibited either synergy (36%), additive (41%) or indifferent (23%) interactions, however, no antagonistic interactions were observed. The MICs of FLC decreased 2–9 fold when used in combination with the test compounds. Like their precursor eugenol, all the derivatives showed significant impairment of ergosterol biosynthesis in all C. albicans strains coupled with down regulation of the important ergosterol biosynthesis pathway gene-ERG11. The results were further validated by docking studies, which revealed that the inhibitors snugly fitting the active site of the target enzyme, mimicking fluconazole, may well explain their excellent inhibitory activity. Our results suggest that these compounds have a great potential as antifungals, which can be used as chemosensitizing agents with the known antifungal drugs.  相似文献   
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