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81.
Unilateral lung agenesis is a rare congenital condition of unknown etiology. A 33-year-old nullipara with right lung agenesis and scoliosis was admitted to the hospital at 30 weeks of gestation because of oligohydramnios. At 32 weeks she was treated for an upper respiratory tract infection with azithromycin. She went into premature labor at 34 weeks and was delivered by Cesarean for breech presentation. Both mother and infant did well. 相似文献
82.
83.
Martina Pitzer Guenter Esser Martin H. Schmidt Manfred Laucht 《European archives of psychiatry and clinical neuroscience》2009,259(8):445-458
In a high-risk community sample, we examined the role of regulative temperament and emotionality as well as the extent of
gender specificity in the development of externalizing problems. 151 boys and 157 girls born at differing degrees of obstetric
and psychosocial risk were followed from birth into adolescence. In infancy and childhood, NYLS-derived temperamental characteristics
were assessed by a highly structured parent interview and standardized behavioral observations. At age 15 years, externalizing
problems were measured by the Child Behavior Checklist. As revealed by multiple linear regression and logistic regression,
low regulative abilities predicted adolescent behavioral and attentional problems over and above obstetric and psychosocial
risks. Gender specificity was found in the strength of the association rather than in the kind with a stronger long-term prediction
from infant and toddler temperament in girls. Compared to regulative abilities, temperament factors describing aspects of mood and fear/withdrawal versus approach tendencies
played a minor role in the development of externalizing problems. Findings are discussed in terms of gender-specific risk
factors and possible differential developmental trajectories to subtypes of disruptive behavior. 相似文献
84.
C Wilfert JE Aronson DT Beck AR Fleischman MW Kline LM Mofenson GB Scott DW Wara PN Whitley-Williams 《Pediatrics》1999,103(2):509-511
Although the character of acquired immunodeficiency syndrome is changing into a chronic illness, it is estimated that by the end of this century, 80 000 children and adolescents in the United States will be orphaned by parental death caused by human immunodeficiency virus infection. Plans for these children need to be made to ensure not only a stable, consistent environment that provides love and nurturing, but also the medical and social interventions necessary to cope with the tragic loss. Pediatricians should become aware of local laws and community resources and initiate discussion early in the course of parental illness to facilitate planning for the future care and custody of the children. States need to adopt laws and regulations that provide flexible approaches to guardianship and placement of children orphaned by acquired immunodeficiency syndrome. 相似文献
85.
目的:一定量的电磁辐射可引起中枢神经系统神经元的损伤,但其对小胶质细胞的影响尚不清楚。实验观察电磁辐射对小胶质细胞活化状态以及分泌功能的影响,揭示电磁辐射对小胶质细胞及中枢神经损伤的效应关系。方法:实验于2006-08/2007-05在解放军第三军医大学电磁辐射医学防护教育部重点实验室完成。取体外培养的N9小胶质细胞接受X波段脉冲波,平均功率密度为90mW/cm2的电磁波,一次性照射20min,在辐照后0,1,3,6,12,24h等6个时相点观察活化的N9细胞形态学,采用免疫组化的方法观察OX-42的表达情况,用酶联兔疫吸附测定方法检测N9细胞培养上清液中肿瘤坏死因子α的水平,采用硝酸还原酶法检测培养上清液中NO浓度。以未接受电磁波辐照的N9小胶质细胞为假辐照组进行对照。结果:①电磁辐射后3hN9小胶质细胞OX-42表达开始明显增强,并一直持续到辐照后24h,细胞形态由静息状态转变为激活状态;②NO的浓度在辐照后1h开始升高(P<0.05),到辐照后6h达到峰值(P<0.01),12h后趋于恢复,24h后再次明显升高(P<0.05)。③肿瘤坏死因子α水平辐照3h后显著升高(P<0.01),并一直持续到12h,到辐射后24h又再次升高,并达到峰值(P<0.01)。结论:电磁辐射辐照可明显诱导小胶质细胞激活,活化后的小胶质细胞分泌NO、肿瘤坏死因子α等细胞因子的功能增强,分泌大量细胞因子反馈调节引起辐射后期的小胶质细胞激活。 相似文献
86.
Waters WR Nonnecke BJ Palmer MV Robbe-Austermann S Bannantine JP Stabel JR Whipple DL Payeur JB Estes DM Pitzer JE Minion FC 《Clinical and diagnostic laboratory immunology》2004,11(4):729-735
Immunological diagnosis of Mycobacterium bovis infection of cattle is often confounded by cross-reactive responses resulting from exposure to other mycobacterial species, especially Mycobacterium avium. Early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) are dominant gamma interferon (IFN-gamma)-inducing antigens of tuberculous mycobacteria, and they are absent from many environmental nontuberculous mycobacteria. Because M. avium exposure is the primary confounding factor in the diagnosis of M. bovis-infected animals, in vitro responses to a recombinant ESAT-6:CFP-10 (rESAT-6:CFP-10) fusion protein by blood leukocytes from cattle naturally exposed to M. avium or experimentally challenged with Mycobacterium avium subsp. avium or Mycobacterium avium subsp. paratuberculosis were compared to responses by M. bovis-infected cattle. Responses to heterogeneous mycobacterial antigens (i.e., purified protein derivatives [PPDs] and whole-cell sonicates [WCSs]) were also evaluated. Tumor necrosis factor alpha (TNF-alpha), IFN-gamma, and nitric oxide responses by M. bovis-infected cattle to rESAT-6:CFP-10 exceeded (P < 0.05) the corresponding responses by cattle naturally sensitized to M. avium. Experimental infection with M. bovis, M. avium, or M. avium subsp. paratuberculosis induced significant (P < 0.05) IFN-gamma and nitric oxide production to WCS and PPD antigens, regardless of the mycobacterial species used for the preparation of the antigen. Responses to homologous crude antigens generally exceeded responses to heterologous antigens. Nitric oxide and IFN-gamma responses to rESAT-6:CFP-10 by blood leukocytes from M. bovis-infected calves exceeded (P < 0.05) the corresponding responses of noninfected, M. avium-infected, and M. avium subsp. paratuberculosis-infected calves. Despite the reported potential for secretion of immunogenic ESAT-6 and CFP-10 proteins by M. avium and M. avium subsp. paratuberculosis, it appears that use of the rESAT-6:CFP-10 fusion protein will be useful for the detection of tuberculous cattle in herds with pre-existing sensitization to M. avium and/or M. avium subsp. paratuberculosis. 相似文献
87.
88.
Little evidence for genetic susceptibility to influenza A (H5N1) from family clustering data 总被引:2,自引:0,他引:2
Pitzer VE Olsen SJ Bergstrom CT Dowell SF Lipsitch M 《Emerging infectious diseases》2007,13(7):1074-1076
The apparent clustering of human cases of influenza A (H5N1) among blood relatives has been considered as evidence of genetic variation in susceptibility. We show that, by chance alone, a high proportion of clusters are expected to be limited to blood relatives when infection is a rare event. 相似文献
89.
90.
Continuous activation and deactivation of integrin CD11b/CD18 during de novo expression enables rolling neutrophils to immobilize on platelets 总被引:2,自引:3,他引:2
In an in vitro flow model, unstimulated neutrophils rolled steadily over a surface coated with platelets, until superfusion of the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (fMLP) caused a dose-dependent (10(-11) to 10(-7) mol/L) transition from rolling to stationary attachment in seconds, followed more slowly by neutrophil shape change and spreading on the surface, However, at low concentrations of Ca2+ and Mg2+ (0.1 mmol/L and 0.05 mmol/L, respectively, rather than physiologic 1 mmol/L and 0.5 mmol/L), neutrophils first halted but then started to roll again and to detach from the surface over 5 to 10 minutes. At the low cation concentration, stopping was largely inhibited by antibodies to the neutrophil integrins CD18 or CD11b, but not CD11a. When neutrophils were pretreated with antibodies to CD11b or CD18 in 1 mmol/L Ca2+ 0.5 mmol/L Mg2+, stopping was not prevented but delayed. However, if antibodies were also included with the superfused fMLP, stopping was inhibited, and detachment followed. This indicates that CD11b/CD18 was newly expressed during shape change and mediated the second phase of neutrophil immobilization and spreading in a cation-dependent manner. Prestimulated neutrophils also bound to platelets and spread, but immobilization was blocked if they were perfused with antibody to CD18 or CD11b or with low Ca2+ and Mg2+. Examining the cation-dependence further, it was evident that the presence of Mg2+ was essential for integrin-mediated adhesion and that the Mg2+ concentration determined whether immobilization could be maintained or was transient. Continuous superfusion of fMLP was also essential for maintenance of stable adhesion and spreading. Thus, activation of constitutive CD11b/CD18 rapidly and reversibly converted rolling to stationary attachment, whereas maintenance of adhesion and neutrophil spreading required continual expression of additional CD11b/CD18 that was only functional at physiologic Mg2+. Continual activation and deactivation of CD11b/CD18 during de novo expression could mediate immobilization and onward migration of neutrophils in vivo, and activated platelets appear capable of supporting this process as well as endothelial cells. 相似文献