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991.
OBJECTIVE: To assess the safety and immunogenicity of three doses of a five-valent (types 6B, 23F, 14, 18C, and 19F) pneumococcal conjugate vaccine (PCV) among children younger than 2 years who are and are not infected with human immunodeficiency virus (HIV). METHODS: A convenience sample of 18 HIV-infected children 2 years and younger (mean, 12.9 months) received three doses (each separated by 2 months) of PCV. An additional convenience sample of 33 non-HIV-infected children of virtually identical age, race, and sex as the HIV-infected group were randomized in a double-blind fashion to receive three doses of PCV or saline placebo. Safety data were collected for 72 hours after each vaccination. Sera were obtained before each and 1 month after the third vaccination to determine vaccine type-specific immunoglobulin G pneumococcal antibody titers by an enzyme-linked immunosorbent assay. RESULTS: Seventeen HIV- and 30 non-HIV-infected children completed the study. The PCV was well tolerated by both HIV- and non-HIV-infected children. No significant differences in local or systemic reactions were noted between HIV- and non-HIV-infected PCV or placebo recipients. Three doses of PCV were immunogenic, as evidenced by 16- to 659-fold increases in type-specific geometric mean antibody titers over prevaccination levels in HIV- and non-HIV-infected children. With respect to an arbitrary protective level, 78% of the antibody titers from HIV-infected children and 88% of the titers from non-HIV-infected children were 1.0 microgram/mL or greater 1 month after the third PCV dose. HIV-infected children with milder disease (Centers for Disease Control and Prevention classes N1-2, A1-2, and B1) were more likely to have protective antibody titers after the first and second PCV doses than HIV-infected children with more advanced disease (Centers for Disease Control and Prevention classes N3, A3, B2-3, and C1-3). However, after the third PCV dose, these differences disappeared. CONCLUSION: Three doses of PCV seem safe and immunogenic in both HIV- and non-HIV-infected children younger than 2 years. This type of vaccine should result in a marked reduction in systemic pneumococcal disease in both HIV- and non-HIV-infected children. Given the high incidence of invasive pneumococcal disease in HIV-infected children, this vaccine may markedly improve the quality of life for this unfortunate group of children. 相似文献
992.
M Weinreb PJ Day F Niggli JE Powell F Raafat PB Hesseling JW Schneider PS Hartley F Tzortzatou-Stathopoulou ER Khalek A Mangoud UR El-Safy F Madanat M Al Sheyyab C Mpofu T Revesz R Rafii K Tiedemann KD Waters JC Barrantes A Nyongo MS Riyat JR Mann 《Archives of disease in childhood》1996,74(1):27-31
Recent studies have suggested that Epstein-Barr virus (EBV) may play a role in the aetiology of Hodgkin's disease. To determine the role of EBV in childhood Hodgkin's disease in different geographical areas, immunohistochemical staining and in situ hybridisation were used to analyse latent membrane protein 1 (LMP 1) and small nuclear non-transcribed RNAs (EBER-1) respectively. Testing for EBV within the Reed-Sternberg and Hodgkin's cells was carried out in childhood Hodgkin's disease from 10 different countries. The proportion of LMP 1 positive cases varied significantly, being 50% of cases from the United Kingdom (38/75), South Africa (9/18), Egypt (7/14), and Jordan (8/16), 60% from the United Arab Emirates (6/10), 70% from Australia (11/16), 81% from Costa Rica (34/42), 88% from Iran (7/8), 90% from Greece (20/22), and 100% of the 56 cases from Kenya. A sensitive polymerase chain reaction based EBV strain typing technique was established using archival tissues. EBV strain type 1 was shown to be predominant in childhood Hodgkin's disease from the United Kingdom, South Africa, Australia, and Greece. Type 2 was predominant in Egypt. EBV strain types 1 and 2 were both detected in some cases of childhood Hodgkin's disease in the United Kingdom, Costa Rica, and Kenya. The high incidence of EBV and the presence especially in developing countries of dual infection with both strain types 1 and 2 may reflect socioeconomic conditions leading to malnutrition induced immunological impairment. The possibility of HIV infection also needs to be explored. 相似文献
993.
In adults greater energy expenditure, primarily on physical activity, is associated with greater leanness. Such an association has proved more difficult to demonstrate in infants, partly due to the difficulty of measuring fatness and free living energy expenditure in this age group. Stable isotope techniques now make such investigations more viable. OBJECTIVE: The relationship between body composition and energy expenditure was investigated in 12 week infants. METHODS: Total energy expenditure and fat mass were estimated using the doubly labelled water technique. SUBJECTS: 92 normal healthy infants. RESULTS: Fat mass was correlated with both triceps and subscapular skinfold thicknesses (p < 0.001). After controlling for body size, age was a significant predictor of fat mass (p = 0.003), whereas total energy expenditure was not (p = 0.463). CONCLUSIONS: The cross sectional link between activity level and fatness in young infants, reported previously, does not persist when energy expenditure is considered. 相似文献
994.
Maximal oxygen consumption (V? max, liters min?1) was measured in 60 nutritionally normal and 74 marginally undernourished girls 6–16 years of age and 27 upper socioeconomic (UEC) women and 22 women living in economically deprived conditions (LEC) in Cali, Colombia. All girls were recruited from the LEC neighborhoods. Lower values for V? max (liters min?1) in undernourished girls were replaced by a nutritionally normal status in adulthood in which V? max was not significantly different from that measured in UEC women. Physical condition varied from average to fair in the younger to older subjects compared to women from industrialized countries. When V? max is expressed as ml min?1 kg?1 of lean body mass (LBM), all age and group effects disappear, confirming regression analysis which demonstrated a close relationship (r2 = 0.81) between V? max (liters min?1) and LBM in which there were no significant differences between nutritional or socioeconomic groups. © 1994 Wiley-Liss, Inc. 相似文献
995.
JC Le Huec F Liquois O Leger D Chauveaux D Midy A Le Rebeller 《Surgical and radiologic anatomy : SRA》1995,17(2):121-128
Summary The data on the fasciocutaneous vascularisation of the medial aspect of the arm are incomplete in the literature. This study presents the methodology and results of an anatomic study on 19 upper limbs with arterial injection. The vascularisation of the upper part of this region is provided in 68% of cases by the superficial fasciocutaneous branch (SFCB) of the superior ulnar collateral artery (SUC), that of the middle and lower part by 3–4 fasciocutaneous pedicles originating from the SUC which are prolonged distally by the recurrent posterior ulnar artery. The SFCB has important relations with the ulnar nerve; it travels dorsal to the nerve in 64% of cases and then allows the raising of a distally-pedicled ulnar flap with a 3 : 1 ratio. In other anatomic configurations, a flap with retrograde flow supplied by the inferior pedicles of the SUC can always be raised. Its ratio is then 2 : 1. this flap allows coverage of all cases of posterior or anterior losses of substance at the elbow. These results supplement the data required for the raising of a distally-pedicled medial brachial flap. but also of a proximally-pedicled superior medial brachial flap and of a free superior medial brachial flap transposed by microsurgical means.
Etude de la vascularisation fasciocutanée de la face médiale du bras. Applications chirurgicales
Résumé Les connaissances sur la vascularisation fascio-cutanée de la face médiale du bras sont incomplètes dans la littérature. Cette étude présente la méthodologie et les résultats d'une étude anatomique sur 19 membres thoraciques avec injection artérielle. La vascularisation de la partie supérieure de cette région est assurée dans 68% des cas par la branche superficielle fasciocutanée (BSFC) de l'a. collatérale ulnaire supérieure (CUS), celle des parties moyenne et inférieure par 3 ou 4 pédicules fascio-cutanés issus de la CUS, qui se prolongent distalement par le rameau postérieur de l'a. récurrente ulnaire. La BSFC contracte des rapports importants avec le n. ulnaire, elle passe à la face dorsale du nerf dans 64% des cas et permet alors la levée d'un lambeau ulnaire à pédicule distal de ratio 3 sur 1. Dans les autres configurations anatomiques, un lambeau à flux rétrograde vascularisé par les pédicules inférieurs de la CUS est toujours prélevable. Son ratio est alors de 2 sur 1. Ce lambeau permet dans tous les cas la couverture de pertes de substance postérieures ou antérieures du coude. Ces résultats permettent de compléter les connaissances nécessaires à la levée du lambeau brachial médial à pédicule distal, mais aussi du lambeau brachial médial supérieur à pédicule proximal et du lambeau libre brachial médial supérieur transposé par méthode microchirurgicale.相似文献
996.
Jemma J Taitz Jian K Tan Camille Potier-Villette Duan Ni Nicholas JC King Ralph Nanan Laurence Macia 《European journal of immunology》2023,53(7):2250163
The gut microbiota has co-evolved with its host, and commensal bacteria can influence both the host's immune development and function. Recently, a role has emerged for bacterial extracellular vesicles (BEVs) as potent immune modulators. BEVs are nanosized membrane vesicles produced by all bacteria, possessing the membrane characteristics of the originating bacterium and carrying an internal cargo that may include nucleic acid, proteins, lipids, and metabolites. Thus, BEVs possess multiple avenues for regulating immune processes, and have been implicated in allergic, autoimmune, and metabolic diseases. BEVs are biodistributed locally in the gut, and also systemically, and thus have the potential to affect both the local and systemic immune responses. The production of gut microbiota-derived BEVs is regulated by host factors such as diet and antibiotic usage. Specifically, all aspects of nutrition, including macronutrients (protein, carbohydrates, and fat), micronutrients (vitamins and minerals), and food additives (the antimicrobial sodium benzoate), can regulate BEV production. This review summarizes current knowledge of the powerful links between nutrition, antibiotics, gut microbiota-derived BEV, and their effects on immunity and disease development. It highlights the potential of targeting or utilizing gut microbiota-derived BEV as a therapeutic intervention. 相似文献
997.
HPLC法测定鼻渊灵冲剂中黄芩苷含量 总被引:5,自引:2,他引:3
目的 :建立了高效液相色谱法测定鼻渊灵冲剂中黄芩苷含量的方法。方法 :样品水溶液经聚酰胺柱层析初步分离后 ,用高效液相色谱法测定。色谱条件 :ShimpackCLC -ODSC18柱 ( 6.0 × 1 50mm) ,以甲醇 -水 -磷酸 ( 53∶4 7∶0 .2 )为流动相 ,检测波长 2 76nm。结果 :线性范围 0 .0 8~ 0 .4 0 μg ,平均回收率为 95.93 % ,RSD =1 .1 2 % (n =5)。结论 :本法简便 ,灵敏度高 ,重现性好 ,可作为该制剂的质量控制方法。 相似文献
998.
磺酸基邻苯二甲酰亚氨甲基酞菁锌C光动力效应诱导肿瘤细胞凋亡 总被引:2,自引:0,他引:2
目的:研究新型光敏剂磺酸基邻苯二甲酰亚胺甲基酞菁锌C光动力效应诱导肿瘤细胞凋亡,探索其光动力杀伤机理,方法:用AO/EB荧光染色法,流式细胞仪及电子显微镜观察该光敏剂光动力效应与人白血病K562细胞形态,超微结构及DNA含量的影响,结果:药物作用2h,以红外照射后继续培养3h以上,就可出现明显的细胞凋亡特性征改变。结论:新型光敏剂磺酸基邻苯二甲酰亚氨甲基酞菁锌C光动力杀伤作用与诱导肿瘤细胞凋亡有关 相似文献
999.
1000.
REN Yi-jin JC. Maltha AM Kuijpers-Jagtman 《口腔医学研究》2004,20(3):282-285
目的:比较研究幼鼠和成年鼠正畸牙齿移动过程中的牙根吸收。材料与方法:本研究包括两组大鼠,其中幼鼠30只(年龄约6周),成年鼠30只(年龄约9~12个月)。大鼠上颌牙一侧用于实验侧,另一侧用于对照。实验侧的三颗磨牙用结扎丝颌粘接剂固为一个整体,在超弹性拉簧作用下(力值为0.1牛顿)向切牙侧移动。1,2,4,8和12周时给予大鼠过量麻醉剂,材料用于组织学研究。上颌第一磨牙的近中颊侧根为根吸收研究对象。压力侧和张力侧的牙根吸收程度在显微镜下进行长度测量。实验侧与对照侧,压力侧与张力侧,幼鼠与成年鼠之间的牙根吸收程度分别以实验时间为参照,在统计学手段下进行了组间和组内分析和比较,以探讨牙齿移动时间和年龄因素对于牙根吸收的影响。结果:实验侧的牙根吸收在幼鼠与成年鼠之间在1,2,4,8周时均没有统计学差异。而在第12周时,成年鼠实验侧牙根吸收大于幼鼠(P<0.05)。成年鼠实验组压力侧的牙根吸收明显大于对照组压力侧,而在幼鼠组没有发现这一差异。两组年龄幼鼠的实验组其压力侧和张力侧的牙根吸收均高度相关。结论:相对于对照侧,正畸牙齿移动并没有在幼鼠的实验侧诱发更多的牙根吸收。在成年鼠,长期的正畸作用力倾向于诱发更多的牙根吸收。这些研究结果表明对于正畸成年病人的后期治疗要更加注意防止牙根吸收。 相似文献