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101.
M. J. Trovoada L. Pereira L. Gusmão A. Abade A. Amorim M. J. Prata 《Annals of human genetics》2004,68(1):40-54
We have analysed the matrilineal genetic composition of three self‐reported ethnic groups from São Tomé e Príncipe (Gulf of Guinea), an African archipelago whose settlement begun in the late fifteenth century. Sequence data from the hypervariable segments I (HVS‐I) and II (HVS‐II) were obtained for 30 Angolares, 35 Forros and 38 Tongas. The repertory of mtDNA lineages in São Tomé e Príncipe denoted a fully African maternal pool, primarily arisen from a Central/Southwestern substratum. The absence of any lineages of putative European descent means that the European impact at the mitochondrial pool was virtually nil. Angolares showed a clear reduction of mtDNA diversity and a slight genetic differentiation relative to Tongas or Forros, whereas the latter two groups did not present any signs of genetic boundaries between each other. The data obtained here reinforce the depiction of genetic substructuring in São Tomé e Príncipe previously derived from Y‐chromosome STRs. In addition, the crossing of mtDNA and Y‐STR information led to the inference that the female mediated gene flow within the archipelago was less restricted than the male, a pattern that could be framed in the cultural traditions and socio‐historical interactions among the groups. 相似文献
102.
孤独症患儿脑干听觉诱发电位研究 总被引:1,自引:0,他引:1
目的 :探讨孤独症患儿脑干听觉诱发电位 (BAEP)的表现。方法 :将研究对象分 3组 :(I)孤独症组 (AD ;2 2例 ) ;(II)单纯智力低下组 (MR ,2 0例 ) ;(III)正常对照组 (NG ,30例 )。智商测验采用 0 - 4岁小儿神经心理发育量表及韦氏智力量表 ;研究对象给予脑干听觉诱发电位测试。结果 :(1 )ADBAEP之III、V波潜伏期及I-III,I-V波峰间期 (IPL)较NG延长 (P <0 0 0 1 )。(2 )ADBAEP之III波潜伏期及I-III波IPL较MR组延长 (P <0 0 0 5)。 (3) :MRV波潜伏期及III-V、I-V波IPL较NG延长 (P <0 0 0 1 )。结论 :(1 )孤独症患儿的脑干听觉诱发电位异常 ,尤其是脑干传导时间 (BTT)的延长 ,提示脑干机能障碍导致信息向大脑传递通路的损害可能是造成孤独症患儿在认知、社会及语言能力等方面异常发育的原因之一。 (2 )孤独症患儿BAEP异常原因可能与孤独症本病特性有关而非伴随智力低下所致。 相似文献
103.
The telemedicine and medical remote monitoring in particular, today represents an effective solution to the health professional shortcomings facing to the increasing older population. In addition to the comfort of being at home, this system decreases the cost of long hospitalization. The proposed system achieves the home medical telesurveillance by means of microphones and medical sensors to detect a distress situation. This system is designed for elderly people at home or for the patient with chronic illness. The experimental apartment is equipped with medical sensors (tensiometer, oxymeter, balance, etc.), infrared position sensors, and acoustic sensors (1 microphone/room). The originality of the system comes from the replacement of the video surveillance with a sound surveillance. The sound analysis system is divided in two stages: firstly, the detection/extraction of the sounds is operated and secondly, a classification of these sounds in known classes takes place. A wavelet-based algorithm with good performance when applied in noisy environments is proposed. The acoustical classification step uses a Gaussian Mixture Models to classify the sounds according to the 7 predefined classes. The detection algorithm allows an equal error rate of 0% for the signal to noise ratio superior or equal to 10 dB and 4% for the 0 dB. The proposed system coupled with a classical medical telesurveillance system will bring extra information needed for the reliability of the global system. 相似文献
104.
The study of in vivo occupancy of benzodiazepine receptors in rat hippocampus and cerebellum indicates that premazepam reaches only about 70% and 80% occupancy respectively within the dose range used for pharmacological tests in rats. Moreover, at equiactive doses (antileptazol ED50), more brain receptors are occupied by premazepam than by other benzodiazepines, suggesting that premazepam may act as a partial agonist at benzodiazepine receptors, with intrinsic activity lower in cerebellum than in hippocampus. These results may explain the lack of sedative and ataxic properties of premazepam. 相似文献
105.
106.
Daniela Vitucci Angela Amoresano Marcella Nunziato Simona Muoio Andreina Alfieri Giovannangelo Oriani Luca Scalfi Luigi Frusciante Maria Manuela Rigano Piero Pucci Luigi Fontana Pasqualina Buono Francesco Salvatore 《Nutrients》2021,13(4)
The isoforms of lycopene, carotenoids, and their derivatives including precursors of vitamin A are compounds relevant for preventing chronic degenerative diseases such as cardiovascular diseases and cancer. Tomatoes are a major source of these compounds. However, cooking and successive metabolic processes determine the bioavailability of tomatoes in human nutrition. To evaluate the effect of acute/chronic cooking procedures on the bioavailability of lycopene and carotene isoforms in human plasma, we measured the blood levels of these compounds and of the serum antioxidant potential in volunteers after a meal containing two different types of tomato sauce (rustic or strained). Using a randomized cross-over administration design, healthy volunteers were studied, and the above indicated compounds were determined by HPLC. The results indicate an increased bioavailability of the estimated compounds and of the serum antioxidant potential with both types of tomato purée and the subsequently derived sauces (the increase was greater with strained purée). This study sheds light on the content of nutrient precursors of vitamin A and other antioxidant compounds derived from tomatoes cooked with different strategies. Lastly, our study indicates that strained purée should be preferred over rustic purée. 相似文献
107.
Katrin Gaardbo Kuhn Anne Kathrine Hvass Annette Hartvig Christiansen Steen Ethelberg Susan Alice Cowan 《Emerging infectious diseases》2021,27(4):1133
Campylobacteriosis is a disease of worldwide importance, but aspects of its transmission dynamics, particularly risk factors, are still poorly understood. We used data from a matched case-control study of 4,269 men who have sex with men (MSM) and 26,215 controls, combined with national surveillance data on Campylobacter spp., Salmonella spp., and Shigella spp., to calculate matched odds ratios (mORs) for infection among MSM and controls. MSM had higher odds of Campylobacter (mOR 14, 95% CI 10–21) and Shigella (mOR 74, 95% CI 27–203) infections, but not Salmonella (mOR 0.2, 95% CI 0–13), and were less likely than controls to have acquired Campylobacter infection abroad (χ2 = 21; p<0.001). Our results confirm that sexual contact is a risk factor for campylobacteriosis and also suggest explanations for unique features of Campylobacter epidemiology. These findings provide a baseline for updating infection risk guidelines to the general population. 相似文献
108.
乙肝清胶囊对实验性肝损伤的保护作用 总被引:1,自引:0,他引:1
目的:通过本实验观察乙肝清胶囊的保肝降酶作用。方法:实验采用四氯化碳(CCl4)和D-氨基半乳糖(D-Gal),造成动物急性实验性肝损伤,测定小鼠和大鼠血清GPT和LDH,并进行组织形态学观察。结果:乙肝清胶囊灌胃给药对CCl4和D-Gal急性肝损伤所引起的小鼠和大鼠GPT和LDH升高,均具有明显的抑制作用,且对小鼠和大鼠肝组织病理损伤具有一定保护作用,其1-2g/kg与联苯双酯15mg/kg作用效果接近。结论:乙肝清胶囊对化学物质的所引起的小鼠和大鼠急性肝损伤,具有保肝降酶作用。 相似文献
109.
兔角膜缘上皮细胞体外培养及其生物学特性的初步研究 总被引:11,自引:3,他引:8
目的:建立体外培养兔角膜缘上皮细胞的方法,观察其体外生长的生物学特性。方法:应用组织培养的方法,对兔角膜缘上皮细胞进行体外原代和传代培养,用倒置显微镜观察培养的兔角膜缘上皮细胞体外生长的特征,用苏木精-伊红染色、糖原(PAS)染色,细胞角蛋白免疫组化染色和电镜检查的方法对培养细胞进行形态学检查和鉴定。结果:兔角膜缘上皮细胞可以在体外成功的培养传代,原代培养细胞大多48h贴壁,5天后旺盛生长,15天形成单层,传代培养细胞次日贴壁10天形成单层。细胞角蛋白AE1单克隆抗体染色阳性,PAS染色阴性,培养细胞呈多角形,细胞表面具有丰富的微绒毛,细胞之间有桥粒连接,结论:应用组织培养的方法可以成功获得原代和传代培养的兔角膜缘上皮细胞,培养的细胞具有与正常兔角膜上皮细胞相一致的生物学特性。 相似文献
110.
银翘解毒丸中微量元素的测定 总被引:4,自引:0,他引:4
目的 :对银翘解毒丸中微量元素进行测定。方法 :试样经过化学处理 ,采用原子吸收光谱法。结果 :方法简便、重现性好。结论 :可以应用于银翘解毒丸的质量控制和药理研究参考 相似文献