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31.
Bonnie J. Baty Lynn B. Jorde Brent L. Blackburn John C. Carey 《American journal of medical genetics. Part A》1994,49(2):189-194
Developmental data were abstracted from medical records on 50 trisomy 18 individuals ranging in age from 1 to 232 months and 12 trisomy 13 individuals ranging in age from 1 to 130 months. Data on the age when trisomy 18 and trisomy 13 children achieved developmental skills were collected from a larger group of 62 trisomy 18 individuals and 14 trisomy 13 individuals whose families filled out parent questionnaires. Developmental quotient (DQ), defined as developmental age divided by chronological age, averaged 0.18 for trisomy 18 and 0.25 for trisomy 13. There was a dramatic drop in DQ from infancy to later childhood. The highest DQs and the greatest variation in DQs were in the first 2–3 years of life. Developmental ages in 7 skill areas were significantly different, with daily living and receptive language having the highest values and motor and communication skills having the lowest. When chronological age was taken into account, there was no significant difference in DQs in the same 7 skill areas, although there was a trend that was similar to the pattern of differences with developmental age. Older children could use a walker, understand words and phrases, use a few words and/or signs, crawl, follow simple commands, recognize and interact with others, and play independently. Walking and some toileting skills were also reported for trisomy 13. Although individuals with trisomy 18 and trisomy 13 were clearly functioning in the severe to profound developmentally handicapped range, they did achieve some psychomotor maturation and always continued to learn. © 1994 Wiley-Liss, Inc. 相似文献
32.
Trang T. Duong Joanne St. Louis Joseph J. Gilbert Fred D. Finkelman Gill H. Strejan 《Journal of neuroimmunology》1992,36(2-3)
SJL/J mice challenged with myelin basic protein (MBP) in complete Freund's adjuvant (CFA) developed only mild chronic-relapsing experimental allergic encephalomyelitis (EAE) with very low incidence. However, treatment of challenged mice with anti-infeferonγ (IFN-γ) monoclonal antibody (mAb) determined severe disease in all cases. Similarly, in passive EAE, the addition of anti-IFN-γ to the in vitro MBP-activated cells at the time of transfer led to significant disease exacerbation in all recipients. The disease enhancing effect was observed only when the mAb was given at the time of active challenge or of passive transfer, but not at later times. Anti-interleukin-2 (IL-2) antibody had only a marginal effect in the active induction, but drastically reduced the manifestations of passive EAE, even when mixed with a disease-enhancing dose of anti-IFN-γ. These findings support the notion that IL-2 is required for disease induction whereas IFN-γ plays a disease-limiting role early in the development of EAE. 相似文献
33.
34.
Lactate dehydrogenase (LDH, EC 1.1.1.27) catalyzes an exchange reaction between pyruvate and lactate. It is demonstrated here that this reaction is sufficiently fast to cause a significant magnetization (saturation) transfer effect when the 13C resonance of pyruvate is saturated by a continuous-wave (CW) RF pulse. Infusion of [2-(13)C]glucose was used to allow labeling of pyruvate C2 at 207.9 ppm to determine the pseudo first-order rate constant of the unidirectional lactate-->pyruvate flux in vivo. During systemic administration of GABAA receptor antagonist bicuculline, this pseudo first-order rate constant was determined to be 0.08+/-0.01 s-1 (mean+/-SD, N=4) in halothane-anesthetized adult rat brains. In 9L and C6 rat glioma models, the 13C saturation transfer effect of the LDH reaction was also detected in vivo. Our results demonstrate that the 13C magnetization transfer effect of the LDH reaction may be useful as a novel marker for utilizing noninvasive in vivo MRS to study many physiological and pathological conditions, such as cancer. 相似文献
35.
肿瘤微环境对树突细胞功能状态的影响 总被引:2,自引:0,他引:2
目的:探讨肿瘤细胞分泌的可溶性细胞因子营造的微环境对树突细胞(DCs,dendritic cells)的分化发育的影响,以进一步揭示肿瘤的免疫逃逸机制。方法:用免疫磁珠从人外周血分离CD14^ 单核细胞,加入粒细胞巨噬细胞集落刺激因子(GM-CSF)、白细胞介素4(IL-4)和人白血病细胞Jurkat培养上清液体外培养DCs,以正常培养诱导的DCs作为对照,采用傅立叶变换红外光谱(FTIR)技术分析人白血病细胞培养上清液对DCs分化发育的影响。结果:正常培养DCs与肿瘤上清液培养的DCs相比,在细胞内蛋白质和核酸的相对含量和细胞内消耗葡萄糖重新合成磷脂的量方面差异无显著性,但是,在细胞的转录状态方面差异有显著性。结论:肿瘤细胞上清液培养液所营造的微环境细胞转录水平上对DCs的功能状态有明显的抑制作用。 相似文献
36.
Summary In order to study the immune function of patients on maintenance hemodialysis (MHD), we assayed NK cell cytotoxicity against
K562 targets in 40 patients on MHD, and the production of IL-2 and IFN in peripheral blood mononuclear cells (PBMC) after PHA
stimulation, in contrast to those in normal controls. The results showed that NK cell activity and IL-2 and IFN levels were
markedly lower in the patients than in the controls. Afeter a single dialysis, NK cell activity as well as IL-2 and IFN levels
were elevated to different extent. But there was no significant change in patients after long-term dialysis. There was a positive
correlation between the NK cell activity and IL-2 and IFN activity in the controls, but no such correlation was found in the
patients on MHD. There was a positive correlation between the NK cell activity and IL-2 activity in patients after dialysis,
suggesting that immune function were impaired in the patients on MHD, with a decline in the activity of NK cell and IL-2 and
IFN, and a disorder of immune regulation cycle. These abnormal immune impairments in the patients could be partly corrected
by hemodialysis. However, long-term hemodialysis is not much helpful in the improvement of patient’s immune function. 相似文献
37.
Interleukin-5 has a specific role in various eosinophilic activities. It is the predominant cytokine produces by activated T-lymphocytes isolated from patients with idiopathic hypereosinophilic syndrome. We studied a young patient suffering from idiopathic hypereosinophilic syndrome who presented with Horner's syndrome, peripheral neuropathy and skin ulcers. The IL-5 gene expression by CD4+ T-lymphocytes and the peripheral eosinophil count were raised. The skin ulcers continued to deteriorate despite a swift reduction of the IL-5 gene expression and peripheral eosinophil count following systemic corticosteroid treatment. We suggest that peripheral eosinophilia may not be responsible for the damage in skin lesions and more aggressive treatment may be required. 相似文献
38.
Christian Foged Christer Halldin Christian Loc’h Bernard Mazière Stefan Pauli Mariannick Maziére Holger C. Hansen Tetsuya Suhara Carl-Gunnar Swahn Per Karlsson Lars Farde 《European journal of nuclear medicine and molecular imaging》1997,24(10):1261-1267
NNC 13-8241 has recently been labelled with iodine-123 and developed as a metabolically stable benzodiazepine receptor ligand
for single-photon emission computed tomography (SPECT) in monkeys and man. NNC 13-8199 is a bromo-analogue of NNC 13-8241.
This partial agonist binds selectively and with subnanomolar affinity to the benzodiazepine receptors. We prepared 76Br labelled NNC 13-8199 from the trimethyltin precursor by the chloramine-T method. Carbon-11 labelled NNC 13-8199 was synthesised
by N-alkylation of the nitrogen of the amide group with [11C]methyl iodide. Positron emission tomography (PET) examination with the two radioligands in monkeys demonstrated a high uptake
of radioactivity in the occipital, temporal and frontal cortex. In the study with [76Br]NNC 13-8199, the monkey brain uptake continued to increase until the time of displacement with flumazenil at 215 min after
injection. For both radioligands the radioactivity in the cortical brain regions was markedly reduced after displacement with
flumazenil. More than 98% of the radioactivity in monkey plasma represented unchanged radioligand 40 min after injection.
The low degree of metabolism indicates that NNC 13-8199 is metabolically much more stable than hitherto developed PET radioligands
for imaging of benzodiazepine receptors in the primate brain. [76Br]NNC 13-8199 has potential as a radioligand in human PET studies using models where a slow metabolism is an advantage.
Received 19 April and in revised form 10 June 1997 相似文献
39.
大鼠坐骨神经慢性挤压性损伤后痛阈和血清IL-6的变化及相关性研究 总被引:2,自引:0,他引:2
目的:通过大鼠坐骨神经慢性挤压伤(CCI)神经性疼痛模型的热敏变化及血清中IL-6含量的变化,探讨血清IL-6在神经性疼痛形成中的作用及可能机制.方法:36只250~300g的健康雄性Wistar大鼠,在戊巴比妥钠麻醉下于大腿中部暴露坐骨神经并作结扎,取对侧大腿坐骨神经暴露作为模拟对照(B组).术后1,3,5,7,9,11,13,15 d测定大鼠(n=12)两侧后爪对热敏阈值的变化.于术后第15 d处死大鼠,取血清,ELISA法测定IL-6浓度.结果:大鼠双侧后爪(CCI和B)的收缩潜伏期在术后第3,5,7,9,11,13,15 d有显著差异;CCI组血清IL-6与对照组比较有显著差异.结论:IL-6与大鼠坐骨神经慢性挤压性损伤后出现的神经源性疼痛过敏有关. 相似文献
40.