Measurement of brain perfusion by volume-localized NMR spectroscopy using inversion of arterial water spins: accounting for transit time and cross-relaxation.

The theoretical model for perfusion measurement by NMR using arterial labeling of endogenous water is extended to include the effects of transit time and cross-relaxation of tissue water with macromolecules. Water magnetization in rat brain is monitored using the STEAM method to simultaneously determine the transit time, magnetization transfer rate constant, and perfusion. The results show that the transit time in rat brain is quite short, and thus its effect on perfusion measurement is small. It is also demonstrated both theoretically and experimentally that the steady-state effects of cross-relaxation with macromolecules on perfusion measurement are accounted for by a proper control experiment.     

Activation of phospholipase D by platelet-derived growth factor (PDGF) in rat C6 glioma cells: possible role in mitogenic signal transduction.

The effects of platelet-derived growth factor (PDGF) on phospholipase D (PLD) activity and deoxyribonucleic acid (DNA) synthesis in rat C6 glioma cells have been investigated. Pretreatment of serum-starved C6 cells with PDGF results in enhanced choline production and the phosphatidylethanol (PEt) formation in the presence of ethanol, indicating the activation of PLD acting on phosphatidylcholine (PC). The dose-response curve for choline generation and DNA synthesis were comparable. In addition, the effects of PDGF on both PEt formation and [3H]thymidine incorporation into acid-precipitable material was blocked by the potent protein kinase C (PKC) inhibitor 1-(5-isoquinolinesulphonyl)-2-methylpiperazine (H-7) but not by N-(2-guanidinoethyl)-5-isoquinolinesulphonamide (HA1004), a relatively weak inhibitor of PKC, suggesting that PDGF plays an important role as a positive regulator of glioma cell growth via a PLD-mediated mitogenic signal transduction cascades, which depends largely on the activation of PKC.     

妊娠期肝内胆汁淤积症与血清甘胆酸的关系

检测了７４例正常足月妊娠妇女和５６例妊娠期肝内胆汁淤积症（ＩＣＰ）患血清甘胆酸（ＣＧ）的浓度，结果ＩＣＰ患血ＣＧ浓度显升高（１３．５２±９．５４ｍｇ／Ｌ），为正常孕妇（２．６７±１．９２ｍｇ／Ｌ）的５～１０倍，根据血ＣＧ浓度将ＩＣＰ患分为〈１０、１０～２０，〉２０ｍｇ／Ｌ３组，将３组胎儿出生情况与正常组相对照，结果显示血ＣＧ浓度〈１０ｍｇ／Ｌ组羊水胎粪污染率及新生儿窒息率与正常组无差异，而     

Assessment of exposure to arsenic among smelter workers: A five-year follow-up

In a group of 43 smelter workers exposed to inorganic arsenic dust for 13-45 years, nerve conduction velocities (NCVs) were significantly lower in two peripheral nerves as compared with matching referents. With multivariate data analysis, a significant negative correlation was found between cumulative absorption of arsenic and NCV in four examined nerves and the sural amplitude. Clinical symptoms of neuropathy and other symptoms related to arsenic exposure were moderate, though the difference between the groups was significant. The mean total absorption of arsenic was calculated to be less than 5 g, and the maximal absorption about 20 g. These data indicate that the adverse effect of arsenic on the peripheral nerves is dependent on long-term exposure rather than on short-term fluctuations in exposure levels. © 1994 Wiley-Liss, Inc.     

Neuromuscular block with vecuronium reduces the rapidly extracted auditory evoked potentials index during steady state anesthesia

PURPOSE: During clinical monitoring, vecuronium appeared to reduce the rapidly extracted auditory evoked potentials index (A-line ARX index or AAI) to some extent. A prospective and randomized study was designed to analyze this phenomenon. METHODS: Forty adult patients undergoing elective surgery were studied. After tracheal intubation, anesthesia was maintained with an end-tidal isoflurane concentration (F(ET)ISO) of 1.0% for 20 min, then a 10-mL dose of either vecuronium 0.05 mg*kg(-1), 0.1 mg*kg(-1), 0.2 mg*kg(-1) or saline was administered in a randomized, double-blind design. The AAI and bispectral index (BI(hx)) were monitored throughout the study and analyzed off-line. RESULTS: BI(hx) was unaltered after the administration of saline or vecuronium. The mean of the averaged (per patient) AAI values recorded from two minutes to ten minutes after the administration of saline or vecuronium 0.05 mg*kg(-1) did not differ significantly from the corresponding mean recorded from 15 min to 20 min after F(ET)ISO maintained 1.0% (P = 0.678, 0.169), however after the administration of vecuronium 0.1 mg*kg(-1) or 0.2 mg*kg(-1), AAI was reduced from 18.3, 18.0 to 14.8, 13.4 (P = 0.016, 0.017). CONCLUSIONS: Neuromuscular block with vecuronium reduces AAI in patients during steady state anesthesia without surgical stimuli, while BI(hx) is unaltered. The cut-off values of AAI for events should be determined according to the level of neuromuscular blockade when monitoring the depth of anesthesia/sedation.     

Joint capsule matrix turnover in a rabbit model of chronic joint contractures: Correlation with human contractures.

To evaluate changes in matrix molecules of the joint capsule, the right knees of 24 skeletally mature female NZW rabbits were immobilized while the contralateral limb served as an unoperated control. The immobilization was discontinued at 8 weeks and the rabbits were divided among four groups (n = 6) based on the number of weeks the right knees were remobilized: 0, 8, 16, or 32. Three rabbits (six knees) that did not have operations provided normal control joint capsules. The mRNA levels for collagen types I, II, and III, and MMP-1 and -13 were significantly increased in the joint capsules of the contracture knees in all groups when compared to normal and contralateral limb joint capsules. In contrast, the mRNA levels for TIMP-1, -2, and -3 were decreased in the joint capsules of the contracture knees in all groups when compared to normal and contralateral limb joint capsules. The mRNA levels for lumican and decorin were increased in the joint capsules of the contracture knees in all groups when compared to normal capsules. Many of the changes observed in this animal model are similar to those observed in human joint capsules from posttraumatic elbow contractures, supporting the value of this rabbit model.     

主动吸入药物烟对大鼠一氧化氮的影响

目的　探讨主动吸入药物烟对大鼠NO的影响。方法　制备大鼠主动吸烟模型 ,采用硝酸还原酶法测定各组大鼠血清、肺、心肌及脑组织的NO含量。结果　非药物烟组大鼠血清、肺、心肌及脑组织中NO含量明显低于非给烟对照组 ,药物烟高、中剂量组NO含量明显高于非药物烟组 ,接近非给烟对照组。结论　吸烟对大鼠血液、肺、心肌及脑组织有不同程度的损伤作用 ,使NO含量降低 ;药物烟具有一定的保护和防止NO含量降低的作用。     

前列腺癌去雄激素治疗不良反应的预防和处理

目的观察去雄激素治疗前列腺癌的不良反应,并探讨其预防和治疗。方法回顾性分析1998年7月-2006年1月112例去雄激素治疗晚期前列腺癌的临床资料。结果112例患者中,97例完成了不良反应的调查。随访3-36月,去雄激素治疗后潮热、性功能障碍、病理性骨折发生率分别为46％、75％、4％;患者潮热、精神疲乏、四肢乏力、纳差症状明显加重(P<0．05);性功能明显减退(P<0．05)。12例潮热症状严重者使用抗抑郁药博乐欣(25mg,tid)1-2周症状减轻。7例有骨转移性疼痛或严重骨质疏松患者,应用唑来膦酸4mg静脉滴注,每45d一次,骨痛症状缓解。结论去雄激素对前列腺癌患者生活质量有一定影响。博乐欣可减轻患者潮热症状,唑来膦酸可预防和治疗去雄激素相关的骨质疏松并发症。     

开放手术观察腰椎间盘突出症溶核失败45例分析

目的 通过开放手术观察分析椎间盘髓核化学溶解术治疗腰椎间盘突出症失败原因。方法 收集溶核失败的腰椎间盘突出症45例行开放手术治疗。结果 术中见45例硬膜外脂肪完全消失，43例髓核未见溶解，2例髓核溶解呈糊状但未被吸收，21例伴有侧隐窝狭窄，15例突出物与神经根粘连，20例黄韧带增厚，2例椎管骨性狭窄，14例突出物钙化。结论 腰椎间盘突出症病变间隙合并有侧隐窝狭窄、神经根粘连、椎管狭窄、突出物钙化等，不是溶核治疗的适应证。     

Innervation of the trapezius muscle: is cervical contribution important to its function?

OBJECTIVE: To study the effect of the cervical plexus and the accessory nerve to the function of the trapezius muscle. STUDY DESIGN AND SETTING: Eighteen adult male Sprague-Dawley rats were randomly divided into three groups. The neurotomies were performed in the left sides and the right sides served as within-subject controls. In group A, the accessory nerve was transected. The C2-5 were transected in group B, and both of the accessory nerve and C2-5 were cut in group C. The electrophysiologic, myophysiologic, and histologic changes of the muscles were measured. RESULTS: There were significant differences (P < 0.05) between the three groups in the recovery rates of the transverse area of the muscles. The CMAP recorded from the experimental sides in group B were similar to the control sides. The values of the maximum tension of the tetanus contraction between the two sides showed no differences either (P > 0.05). CONCLUSION: The accessory nerve supplies the most important motor input to the trapezius. Motor innervations of the cervical plexus are not very significant.