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排序方式: 共有493条查询结果,搜索用时 15 毫秒
91.
DK Ng KW Chau C Black TMM Thomas KL Mak & M Boxer 《Journal of paediatrics and child health》1999,35(3):321-323
A case of neonatal Marfan syndrome is presented. The patient was noted to have cardiomegaly and tricuspid regurgitation on antenatal ultrasound scan. She was born with long, slender fingers and toes, an aged appearance and non-paralytic hypotonia. Echocardiogram revealed a dilated right atrium, right ventricle, dysplastic tricuspid valve and severe tricuspid regurgitation. She subsequently died of severe heart failure. Post-mortem examination showed the pathological features of lobar emphysema and cystic medial necrosis of the aorta. These features supported the diagnosis of neonatal Marfan syndrome. Nucleotide sequencing showed substitution of G by A at codon 1032 in exon 25 located in the long arm of chromosome 15. This resulted in the substitution of a cysteine by a tyrosine. A de novo mutation is suggested by the absence of affected family members. 相似文献
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93.
Catherine Mathews Sander M. Eggers Loraine Townsend Leif E. Aarø Petrus J. de Vries Amanda J. Mason-Jones Petra De Koker Tracy McClinton Appollis Yolisa Mtshizana Joy Koech Annegreet Wubs Hein De Vries 《AIDS and behavior》2016,20(9):1821-1840
Young South Africans, especially women, are at high risk of HIV. We evaluated the effects of PREPARE, a multi-component, school-based HIV prevention intervention to delay sexual debut, increase condom use and decrease intimate partner violence (IPV) among young adolescents. We conducted a cluster RCT among Grade eights in 42 high schools. The intervention comprised education sessions, a school health service and a school sexual violence prevention programme. Participants completed questionnaires at baseline, 6 and 12 months. Regression was undertaken to provide ORs or coefficients adjusted for clustering. Of 6244 sampled adolescents, 55.3 % participated. At 12 months there were no differences between intervention and control arms in sexual risk behaviours. Participants in the intervention arm were less likely to report IPV victimisation (35.1 vs. 40.9 %; OR 0.77, 95 % CI 0.61–0.99; t(40) = 2.14) suggesting the intervention shaped intimate partnerships into safer ones, potentially lowering the risk for HIV. 相似文献
94.
Human papillomavirus molecular biology and pathogenesis 总被引:15,自引:0,他引:15
G Sanclemente † DK Gill‡ 《Journal of the European Academy of Dermatology and Venereology》2002,16(3):231-240
Human papillomavirus (HPV) infection is the most common sexually transmitted disease in the world and accounts for an estimated 11% of the global cancer incidence in women. HPV-16 is the most prevalent type detected in cervical cancer and along with types 18, 31, 33 and 45 has been classified as a class I carcinogen. In addition to cervical cancer, HPVs are also associated with the malignant transformation of other mucosal and skin cancers. Thus, the combination of the malignant potential of HPV and its high prevalence of infection confers to it an importance of generalized clinical and virological significance. The natural history of HPV infection with or without treatment varies from spontaneous regression to persistence. The most important mechanism for wart regression appears to be cell-mediated immunity. Cytokines released by keratinocytes or cells of the immune system may play a part in the induction of an effective immune response against HPV infection and the subsequent regression of lesions. This review discusses the molecular biology, pathogenesis and immunology of HPV infections. 相似文献
95.
复合自适应滤波器用于体感诱发电位信噪比的提高 总被引:1,自引:0,他引:1
本研究以可靠、快速提取体感诱发电位为目标,试图解决相干叠加方法既费时又不能反映体感诱发电位时变特征的缺点。运用以自适应噪声减法器和自适应增强器为基础构造的复合自适应滤波器提取体感诱发电位。仿真实验表明,运用复合自适应滤波器可实现从强噪声背景中快速提取体感诱发电位,能更快地识别体感诱发电位的潜伏期及幅值,并且系统性能稳定。 相似文献
96.
Response of Plasmodium falciparum to dihydrofolate reductase inhibitors in Malindi, Kenya 总被引:2,自引:0,他引:2
H C Spencer W W Watkins D G Sixsmith D K Koech 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1986,80(2):201-203
The response of Plasmodium falciparum isolates to dihydrofolate reductase inhibitors (DHFRI) was examined in Malindi, Kenya. All 20 infected children treated with pyrimethamine/sulphadoxine responded. In contrast, after treatment with pyrimethamine, parasitaemia in 9 of 14 infections failed to clear or recrudesced during the seven-day follow-up. In a 48-hour in vitro test, five of six isolates resistant to pyrimethamine in vivo had a minimal inhibitory concentration (MIC) to pyrimethamine greater than or equal to 300 nmoles/1 compared with less than or equal to 100 nmoles/1 for the four sensitive isolates; four isolates did not grow. MIC to M-B 35769, an experimental DHFRI structurally similar to pyrimethamine were the same (six isolates) or 10-fold lower (three isolates). In the laboratory four of five isolates adapted to in vitro culture had the same MICs as in the field while one isolate became less responsive to both drugs. Cycloguanil (the active metabolite of proguanil) was more active in vitro in the laboratory than pyrimethamine or M-B 35769. 相似文献
97.
98.
99.
黄芪皂苷抗实验性肝损伤作用 总被引:21,自引:0,他引:21
两种黄芪苷ASI和SK能对抗D-半乳糖胺,醋氨酚引起的肝损伤。表现为减轻肝毒引起的病变,SGPT降低,肝MDA下降,GSH升高;且三项指标变化呈明显相关。从离体大鼠肝细胞制备法也证明ASI和SK在0.75μmol/L~0.18 nmol/L浓度范围内,可对抗CCl4引起的GPT升高。给小鼠连续灌服ASI 12,50 mg/kg或SK 6,20 mg/kg能提高肝微粒体细胞色素P—450活性。此结果表明,黄芪苷是黄芪抗肝毒损伤的有效成分。其机理除抗生物氧化外,尚与代谢调节作用有关。 相似文献
100.
SC Gandevia GM Allen JE Butler RB Gorman DK McKenzie 《Clinical and experimental pharmacology & physiology》1998,25(10):757-763
1. Given the importance of the ventilatory ‘pump’ muscles, it would not be surprising if they were endowed with both sensory and motor specializations. The present review focuses on some unexpected properties of the respiratory muscle system in human subjects. 2. Although changes in blood gas tension were long held not to influence sensation directly, studies in subjects who are completely paralysed show that increases in arterial CO2 levels elicit strong sensations of respiratory discomfort. 3. Stretch reflexes in human limb muscles contain a monosynaptic spinal excitation and a long-latency excitation. However, inspiratory muscles show an initial inhibition when tested with brief airway occlusions during inspiration. This inhibition does not depend critically on input from pulmonary or upper airway receptors. 4. Human inspiratory muscles (including the diaphragm) have been considered to fatigue during inspiratory resistive loading. However, recent studies using phrenic nerve stimulation to test the force produced by the diaphragm show that carbon dioxide retention (hypoventilation) and voluntary cessation of loading occur before the muscles become overtly fatigued. 相似文献