N-methyl-D-aspartate exposure blocks glutamate toxicity in cultured cerebellar granule cells.

Exposure of cultured cerebellar granule cells to glutamate results in a concentration-dependent (EC50 = 22.7 +/- 0.4 microM) and delayed (24-72 hr) neurotoxicity, which is blocked by the specific N-methyl-D-aspartate (NMDA) receptor antagonists 2-amino-5-phosphovalerate and MK-801 but is unaffected by the non-NMDA receptor antagonists 6-cyano-7-nitroquinoxaline-2,3-dione and 6,7-dinitroquinoxaline-2,3-dione. Although glutamate toxicity in these cells is mediated by the NMDA subtype of glutamate receptor, pretreatment of cerebellar granule cells with subtoxic concentrations of NMDA markedly antagonizes the neurotoxic actions of glutamate, with an IC50 of 55 +/- 4 microM. The neuroprotective effect of NMDA requires a preincubation time of approximately 120 min to be fully manifested and does not require the presence of NMDA during glutamate exposure. These data demonstrate that NMDA receptors mediate both neurotoxicity and neuroprotection in cerebellar granule cells. Among four glutamate receptor agonists tested (NMDA, quisqualate, ibotenate, and kainate), only NMDA was able to provide a robust neuroprotection against glutamate toxicity. Quisqualate was neither neurotoxic nor neuroprotective, whereas ibotenate, which was nontoxic by itself, induced a small degree of neuroprotection. In contrast, kainate, which was neurotoxic to cerebellar granule cells, also provided considerable neuroprotection against glutamate toxicity. Because preincubation of cerebellar granule cells with NMDA fails to alter NMDA receptor-mediated phosphoinositide hydrolysis or the specific binding of [3H]MK-801 to NMDA receptors, it appears that the neuroprotective effects of NMDA are not due to NMDA receptor desensitization.     

体外循环后鱼精蛋白不良反应的预防(附64例报告)

目的探讨体外循环不同途径给予鱼精蛋白所产生的不良反应及地塞米松对这些不良反应的预防作用。方法将 6 4例患者按给药途径及是否预防性给予地塞米松分为 4组 :A1,A2 ,B1和B2 组。A组升主动脉给药 ,B组颈内静脉给药 ;A1,B1组给予地塞米松 ,A2 ,B2 组不给予地塞米松。观察各组注射鱼精蛋白后 3,10 ,2 0 ,30min平均动脉压 (meanarterialpressure ,MAP)、平均肺动脉压 (meanpulmonaryarterialpressure ,MPAP)及气道压力(airwaypressure ,AP)的变化。结果A1组各时间点数据无显著性差异 (P >0 .0 5 ) ,A2 组给予鱼精蛋白 3min后血压下降 (P <0 .0 5 ) ;B1组给予鱼精蛋白 3min后血压下降 (P <0 .0 5 ) ,气道压力升高 (P <0 .0 5 ) ,B2 组给予鱼精蛋白 3,10 ,2 0min后血压明显下降 (P <0 .0 5 ,P <0 .0 1) ,气道压力升高 (P <0 .0 5 ,P <0 .0 1)。结论从主动脉根部注射鱼精蛋白对血流动力学影响较静脉给药小 ,地塞米松对鱼精蛋白的副作用有一定的预防作用     

Further evidence supporting a cause and effect relationship between blood transfusion and earlier cancer recurrence.

Studies of associations between perioperative blood transfusions and later recurrence of solid tumors have yielded conflicting results. A previous analysis of transfused patients suggested that recurrence was associated with transfusion of whole blood as opposed to red blood cell concentrates. Additional analyses were performed on patients with cancers of the colon, rectum, cervix, and prostate to determine if patients receiving whole blood, red blood cells only, or no transfusions had differing outcomes. Patients receiving 1 unit or more of whole blood had uniformly poor outcomes compared with nontransfused patients (p less than 0.001). In contrast, patients receiving only red blood cells had progressively worse recurrence and death rates with increasing numbers of transfusion, suggesting the presence of a dose-effect relationship. Employing multivariate techniques, blood transfusion of less than or equal to 3 units that included any whole blood were independently and significantly associated with earlier recurrence (p = 0.003) and death due to cancer (p = 0.02). Transfusions of less than or equal to 3 units of blood comprised solely of red blood cell concentrates were associated with no greater risk of recurrence than that seen in patients receiving no transfusion (p = 0.50). These results provide a potential explanation for the disparate results reported in studies of blood transfusion and cancer outcome. The marked difference in outcome seen between patients receiving a few units of red blood cells and comparable patients receiving even one unit of whole blood are consistent with the hypothesis that transfusion of stored blood plasma causes earlier tumor recurrence in some instances. Strategies for reducing these risks might include avoidance of whole blood transfusions when only 1-3 units are required, more conservative transfusion practice, use of autologous blood transfusions, and perhaps, use of red blood cells washed free of plasma and white cell debris. Clinical trials to test these hypotheses are urgently needed.     

双针并行内固定在断指再植中的应用（附14例报告）

目的 探讨断指再植中骨折的内固定方法。方法 对2000年10月～2003年3月收治的14例患者17断指采用双针并行髓内贯穿固定骨折，并与同期其他内固定方法进行对比。结果 所有断指均再植成活，随访的10例患者中无1例发生骨不连或骨延迟愈合。平均骨愈合时间5周，关节功能恢复满意。结论 双针并行内固定方法固定更加牢固，更有利于骨折愈合，是一种较为理想的内固定方法。     

24例病毒性、15例化脓性脑炎患者脑脊液中乳酸脱氢酶及同功酶分析

目的 :观察病毒性、化脓性脑炎脑脊液(csf)中乳酸脱氢酶 (LDH)活性及其各同功酶活性百分率的变化。方法:病毒性脑炎24例 ,化脓性脑炎15例 ,酶动力学法检测脑脊液总乳酸脱氢酶 (TLDH)活性 ,琼脂糖凝胶电泳法检测脑脊液中LDH各同功酶活性百分率。结果:病毒性脑炎与对照组比较 ,脑脊液总乳酸脱氢酶 (TLDH)明显降低 (P<0.01) ,LDH1同功酶显著降低 (P<0.01) ,LDH5显著升高 (P<0.01) ;化脓性脑炎与对照组比较脑脊液TLDH明显升高 (P<0.01) ,LDH1同功酶明显降低 (P<0.01) ,LDH5明显升高 (P<0.01)。结论:脑脊液TLDH值的测定可以鉴别病毒性、化脓性脑膜炎 ,检测脑脊液LDH各同功酶活性 (LDH1和LDH5)的变化程度对脑炎的进展及预后有一定的价值。     

经单侧椎板开窗夹闭硬脊膜动静脉瘘

目的　总结经单侧椎板开窗入路夹闭硬脊膜动静脉瘘的经验。方法　回顾性分析了 5 6例经脊髓MR和脊髓血管造影确诊的硬脊膜动静脉瘘患者经单侧椎板开窗夹闭瘘口的临床资料。结果　 5 4例患者术后行脊髓血管造影复查 ,显示瘘口全部消失。 38例患者术后 6个月行脊髓MR复查 ,显示脊髓周围的血管流空影完全消失 ,T2 像髓内高信号影消失或明显减少。 5 4例患者获随访 ,随访时间 3～ 36个月 ,2 4例症状完全消失 ,2 7例症状改善 ,3例无变化。结论　经单侧椎板开窗夹闭瘘口的手术方法是硬脊膜动静脉瘘的首选治疗方法。     

保留胸背神经的背阔肌皮瓣游离移植

目的 为减少背阔肌皮瓣切取时供区的代价，尽可能保留肌皮瓣切取后背阔肌的功能。方法 通过了解胸背神经、血管的解剖特点，切取肌皮瓣时不将胸背神经完全切断，保留部分或全部神经的支配。手术前后对背阔肌的神经肌肉动作电位进行检查，了解术后保留的背阔肌功能。临床应用20例修复下肢或前臂软组织缺损或伴骨外露。结果 19例移植皮瓣成活良好，保留的背阔肌有收缩功能存在。结论 在切取一定大小的背阔肌皮瓣时，保留胸背神经的支配，可减小背阔肌的功能损失，使供区的代价降低，符合皮瓣切取原则。     

骨髓间充质干细胞体外诱导为神经细胞的研究

本实验观察了大鼠MSCs向神经细胞方向的诱导分化情况,以期为MSCs在神经移植领域的临床应用提供理论基础。用含10 ng／ml bFGF+20％FBS的DMEM对MSCs进行预诱导24 h后,以含200μmol／L的BHA+2％DMSO的无血清DMEM对MSCs进行诱导,观察诱导后细胞的光、电镜形态学变化,通过免疫组织化学法对诱导后细胞进行神经细胞表型及神经递质合成酶鉴定。结果显示:MSCs经BHA和DMSO诱导后,80％以上的细胞表现出神经元样形态,胞浆内可见较多Nissl体,并表达nestin、NSE、NF、MAP、SYN,部分诱导后的细胞表达ChAT、TH、GAD;电镜下观察,诱导后细胞核大而圆,核仁明显,胞浆内细胞器发达,可见大量粗面内质网和游离核糖体。提示,MSCs体外可被诱导分化为神经元样细胞,诱导后的细胞有合成某些神经递质的能力并具有发育早期神经元的超微结构特点。     

炎性肠梗阻15例诊治体会

目的探讨炎性肠梗阻的诊断和治疗。方法分析15例炎性肠梗阻的临床特点和治疗。结果15例经保守治疗,其中1例因肠扭转缺血损伤严重,出现全身性炎症反应综合征致多脏器衰竭死亡外,其他病例均痊愈,平均治愈时间为12.6d。结论炎症性肠梗阻由无菌性炎症致广泛肠粘连引起,应用小剂量激素减缓炎症反应,抗生素防止肠道菌群易位,经内镜逆行置入肠减压管及营养支持治疗,多数病例可保守治愈。     

Inhibitory effect of islet amyloid polypeptide of glucose-induced proinsulin biosynthesis in rat insulinoma cells.

Islet amyloid polypeptide (IAPP) has been recently identified as the principal constituent of amyloid deposits in pancreatic islets of patients with type 2 (non-insulin-dependent) diabetes mellitus and causes insulin resistance in some target cells. In addition, glucose-induced insulin secretion is inhibited by IAPP. We studied the effect of IAPP on proinsulin biosynthesis in rat insulinoma (RINr) cells. Glucose at concentrations of 0, 15, 30, 60, 100, and 300 mg/dl stimulated proinsulin biosynthesis in a dose-responsive and and actino-mycin D-inhibitable manner after 6 h of incubation. At a glucose concentration of 300 mg/dl, IAPP decreased the mean responses of proinsulin biosynthesis to 61.2 and 29% at concentrations of 0.1 and 1 microM, respectively, compared with the IAPP-free control. In conclusion, IAPP inhibits glucose-induced proinsulin biosynthesis in RINr cells. IAPP might play an important role in the pathogenesis of type 2 diabetes mellitus.