Magnetic resonance imaging: absence of in vitro cytogenetic damage

Human lymphocytes and Chinese hamster ovary (CHO) cells in culture were exposed for 12 1/2 hours to a magnetic resonance imaging apparatus with a 2.35-Tesla magnet and 100-MHz radio frequency emission. The cells were examined for cytogenetic damage manifested either as chromosome aberrations or sister chromatid exchanges (SCEs), which constitute very sensitive measures of genetic and cellular damage. In either unstimulated or stimulated human lymphocytes, as well as in exponentially growing CHO cells, no increase in either chromosome aberrations or SCEs was found as a result of exposure to these MR conditions. The data indicate that long-term exposure to MR imaging conditions far exceeding those to be found in the clinical situation does not cause cytogenetic damage.     

咪苯嗪酮对TXA2和HHT生成的选择性抑制作用

咪苯嗪酮(CI-914)能抑制大鼠血小板环氧酶和TXA₂合成酶产物HHT的生成,而对脂氧酶产物12-HETE的生成仅高浓度药物才有弱的抑制作用,提示CI-914主要影响花生四烯酸(AA)环氧酶途径,而对脂氧酶途径影响较少。在大鼠血小板和中性白细胞CI-914能抑制TXA₂的生成,同时CI-914还可使白细胞6-keto-PGF_1a和血小板PGE₂的产生量显著增加,提示CI-914在这两种细胞引起了AA的转向合成。上述结果基本证实,CI-914在大鼠中性白细胞和血小板对TXA₂合成酶具有选择性抑制作用。     

Cerebrospinal fluid analyses in migraine patients and controls

To investigate the role of central neurotransmitters in the pathogenesis of migraine, we measured cerebrospinal fluid (CSF) levels of certain amino acids (glycine, taurine, glutamine) and metabolites of biogenic amines (5-hydroxyindoleacetic acid and homovanillic acid) in 38 migraine patients and compared them with the levels from 10 headache-free controls. The levels of taurine, glycine and glutamine were significantly higher in the migraine patients (p < 0.0001 for taurine and glycine; p < 0.0009 for glutamine); there were no significant differences among the three migraine subgroups (infrequent migraine, frequent migraine and transformed migraine). In seven patients subsequently treated with divalproex sodium, CSF taurine levels decreased significantly from pretreatment baseline values. These data support the concept that migraine is at least in part a disorder of central neurotransmission.     

Temporomandibular joint arthrography: comparison of morbidity with ionic and low osmolality contrast media

We compared patient morbidity associated with temporomandibular joint (TMJ) arthrography using both meglumine/sodium diatrizoate (60%) and the new monoacidic dimer, Hexabrix, in a double-blind randomized clinical trial in 31 patients. Patients experienced maximal discomfort from TMJ arthrography with the initial joint filling and joint distension; this rapidly resolved over 10 minutes. Delayed exacerbation of pain is less than described for shoulder arthrography. The newer contrast media promise to decrease patient morbidity with arthrography.     

大剂量甘露醇治疗癌性颅内高压症1例

1 临床资料患者、女性、38岁、因右小细胞肺癌术后16 mo,间断性头痛10 mo,加重1 wk后于2003-01-01入院.在2002-02因枕部疼痛,行头颅CT示: 脑多发转移癌.行多次头颅局部X-刀、γ-刀加全脑预防性放疗和化疗,疗效达部分缓解.2002-12末头痛症状复发,约1.5 h发作1次,伴短暂意识丧失、喷射状呕吐和四肢抽搐.     

A STD/HIV prevention trial among adolescents in managed care

OBJECTIVE: To determine if sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV) infection, risk assessment, and education tools provided as part of office-based primary care reduce adolescent risky sexual behaviors. DESIGN: A randomized intervention trial with 3- and 9-month follow-up. SETTING: Five staff-model managed care sites in Washington, DC (n = 19 pediatricians). PATIENTS: Consecutive 12- to 15-year-olds receiving a general health examination; 81% minority. Participation rate = 215/432 (50%). Nine-month follow-up rate = 197/215 (92%). INTERVENTION: Audiotaped STD risk assessment and education about staying safe (safer = condoms, safest = abstinence). MAIN OUTCOME MEASURES: Adolescent-reported sexual intercourse and condom use. RESULTS: More intervention adolescents reported pediatrician discussion on 11/13 sexual topics. Although more vaginal intercourse (odds ratio [OR] = 2.46, 95% confidence interval [CI] = 1.04-5.84) was reported in the intervention group at 3 months, this was not true of overall sexual intercourse (OR = 1.55, 95% CI =.73-3.32). More sexually active adolescents reported condom use in the intervention group at 3 months (OR = 18.05, 95% CI = 1.27-256.03). At 9 months, there were no group differences in sexual behaviors; however, more signs of STD were reported by the control (7/103) than the intervention group (0/94). CONCLUSIONS: STD risk assessment and education tools administered in a single office visit facilitated STD/HIV prevention education. Any impact on sexual activity and condom use was short-lived. Further research is needed to develop brief, office-based sexual risk reduction for young adolescents.     

塞来昔布在类风湿性关节炎中对甲氨喋呤的药代动力学影响

目的：确定塞来昔布对于经常服用稳定剂量甲氨喋呤（ＭＴＸ）治疗类风湿性关节炎（ＲＡ）患者的肾脏清除率和血浆药代动力学方面的影响。方法：选取１４例至少已服用ＭＴＸ３个月,且每个星期的剂量稳定在５－１５ｍｇ,有类风湿关节炎的成年妇女,随机给予塞来昔布（２００ｍｇ．ｂｉｄ）或安慰剂单盲治疗,每一阶段７,分二阶段交叉试验,研究ＭＴＸ的药代动力学和肾脏平均清除率。结果：当ＭＴＸ和塞来昔布或安慰剂合用时,ＭＴＸ