应用荧光探针H2DCF-DA检测光照致细胞内活性氧产生的初步研究

目的应用荧光显微镜及新型荧光探针H2DCF-DA检测在光源照射过程中人脐静脉血管内皮细胞(ECV304)内活性氧的产生情况。方法将ECV304细胞接种于35mm培养皿中,24h后加入H2DCF-DA,使其终浓度为10μmol/L,孵育30min。利用荧光显微镜的激发光源作为照射光源,在采集荧光图像的同时完成光源照射,光源输出波长范围为460～490nm,功率密度约为100mW/cm2。连续采集DCF的荧光图,观察细胞内DCF荧光的变化情况,采用计算机图像处理和分析技术,求得细胞内不同照射时间点DCF平均荧光强度,进而得到平均荧光强度-时间曲线。另外,使用线粒体特异标记探针MitoFluorRed589与H2DCF-DA共同孵育细胞,分别采集同一细胞的DCF的荧光图和MitoFluorRed589的荧光图,并利用像素-荧光强度分析方法来确定DCF荧光在细胞内的分布位置。结果在光源照射的开始阶段,ECV304细胞内的DCF荧光强度迅速增加,在第10s时便上升至第2s时的2.2倍,但是随着照射时间逐渐延长,荧光强度增幅逐渐变小,到第60s时上升至第2s时的4.7倍。观察时间进一步延长,DCF的荧光强度的变化似乎进入平台期,继而开始出现下降。考察DCF荧光在ECV304细胞内的分布位置主要通过比较细胞内不同区域的I1/I2值,通过图像分析与计算得到线粒体区、细胞核区以及细胞质非线粒体区内I1/I2值分     

肝素钠软膏（海普林）治疗皮质类固醇激素依赖性皮炎疗效观察

目的观察肝素钠软膏（海普林）治疗皮质类固醇激素依赖性皮炎的效果。方法随机抽取部分病例组成对照组，其余病例组成治疗组，分别使用单纯乳剂和肝素钠软膏外涂，配合相关内服药物治疗，比较治疗组和对照组疗效。结果对照组治疗有效率为24．81％，治疗组治疗有效率为52．24％，两组结果差异有非常显著性。结论应用肝素钠软膏外用治疗皮质类固醇激素依赖性皮炎取得了满意的疗效。     

低分子肝素对不稳定型心绞痛病理生理干预作用的研究

目的:观察低分子肝素(LMWH)对不稳定型心绞痛((UAP)的临床症状、心电图、血脂以及内皮素(ET)的影响。方法:前瞻性地将84例UAP患者随机分为两组:对照组使用硝酸甘油、倍他乐克、阿司匹林等药物;治疗组(LMWH组)在上述治疗基础上加用LMWH(速避凝)。治疗前后调查临床症状以及心电图改变,抽血测定血脂、红细胞压积、血小板及内皮素水平的变化。结果:两组治疗后,患者心绞痛发作次数、持续时间以及硝酸甘油的用量明显减少,心电图明显改善,且LMWH组优于对照组(P<0.05)。LMWH治疗后,患者HCT、TC、TG及ET较治疗前明显降低(P<0.05)。对照组血浆ET水平无变化。结论:LMWH对UAP患者不仅具有抗凝抗栓作用,而且可以降低血液粘度、保护血管内皮细胞,纠正脂类代谢紊乱状态,     

Structural variations in the crystal structures of two homologous DL-Leu and Δ-Leu containing peptides+

The similar conformations and interaction modes of Ac-DL-Leu-Nme₂ and Ac-Δ-Leu-NMe₂ molecules in the solid state allow the comparison of their geometrical parameters. The most evident variations are essentially restricted to the α,β-unsaturated side-chain which adopts the Z-disposition. The dimensions of the peptide backbone are much less sensitive to α,β-unsaturation, with a small shortening by 0.04 Å and 0.02 Å of the N-C^α and C^α-C′ bonds, respectively, and an increase by 6° of the N-C^α- C′ bond angle. The ethylenic and amide groups in the Δ-Leu derivative are far from coplanarity, and a significant electronic conjugation of the π-orbital is likely to be rejected.     

Clinical and manometric evaluation of anorectal function following low anterior resection with low anastomotic line using an EEA™ stapler for rectal cancer

Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line, using an EEA^™ stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is a functionally acceptable option for low rectal cancer.     

小鼠轮状病毒EW株VP7基因的克隆及其在重组腺病毒中的表达

目的：构建表达小鼠轮状病毒(EDIM)EW株VP7基因的重组腺病毒，以在小鼠模型上研究轮状病毒的免疫保护机制。方法：用RT-PCR方法扩增EDIM VP7全长cDNA并进行基因序列分析，将所得的VP7基因片段插入腺病毒穿梭质粒pShuttle-CMV，获得重组质粒pShuttleCMV-EVP7，将该质粒与腺病毒骨架质粒pAdEasy-1共转化大肠杆菌BJ5183获得重组腺病毒质粒pAdCMV-EVP7，将该质粒线性化后转染293细胞包装重组腺病毒rvAdEVP7。以rvAdEVP7感染293细胞，并分别应用电子显微镜、PCR、RT-PCR和Western blot等方法观察rvAdEVP7的形态、VP7基因整合、遗传稳定性、VP7基因在细胞内转录及表达等有关生物学特性。结果：获得了小鼠轮状病毒的全长cDNA，重组腺病毒rvAdEVP7具有典型的腺病毒形态，PCR、RT-PCR和Western blot等分子生物学方法分析显示：rvAdEVP7中确有特异性的VP7基因稳定整合；有较好的遗传稳定性；感染293细胞后能有效转录；可表达轮状病毒主要结构蛋白VP7。结论：成功构建含VP7基因的重组腺病毒rvAdEVP7，为进一步研究轮状病毒的免疫保护机制打下了基础。     

Influence of heparin on fibrinogen and D-dimer plasma levels in acute myocardial infarction treated with streptokinase

The purpose of this study was to investigate whether, to whatextent, and through which mechanisms intravenous heparin, administeredbefore and after streptokinase, affects the plasma levels ofD-dimer and fibrinogen in myocardial infarction. Data concerningmortality and incidence of coronary recanalization in patientsreceiving heparin and thrombolytic therapy after acute myocardialinfarction are controversial; furthermore, the mechanisms throughwhich heparin acts in combination with thrombolytic therapyare unclear. Thirty-eight patients with acute myocardial infarctiontreated with streptokinase were considered. Nineteen of themreceived, immediately before the beginning of thrombolytic treatment,a bolus of heparin (100 U. kg¹ intravenously) and, 2 h later,intravenous heparin in doses raising the partial thromboplastintime to 2-2.5 times the normal value (Group 1); the remaining19 did not receive anticoagulant treatment (Group 2). Multipledeterminations of plasma D-dimer and fibrinogen levels wereobtained in all patients before, and in the seven days followingthrombolytic treatment. Six hours after streptokinase, fibrinogendecreased from 304 ± 34 to 61 ± 34 mg. dt¹ inGroup 1 and from 312 ± 29 to 38 ±21 mg. dt¹ inGroup 2 (P<002 versus Group 1). The same difference betweengroups persisted at the 12th and at the 18th hour. D-dimer values,from 0-5 ± 01 \ig. dl¹ in Group 1 and 04 ±01 fig.dt¹ in Group 2, increased at the 1st hour to 37.2 ± 36.5fig. dt¹ and 52.2 ± 39.8 µg. dl¹, respectively.A peak value was reached in both groups at the 6th hour, whichwas followed by a slow decrease. A significant difference betweenthe two groups (P<0.05) was observed at the 1st, 2nd, 4thand 6th hour. An inverse correlation between maximal changesof fibrinogen and of D-dimer was found in both groups (r= 0.89,P<0.001 in Group 1; r=-0.81, P<0.001 in Group 2). The relationship between D-dimer and fibrinogen variations afterstreptokinase and changes induced by heparin, support the hypothesisthat the decrease of fibrinogen, following thrombolysis, isnot only the consequence of its direct degradation, but alsothe result of its transformation by streptokinase into fibrin,fibrin cross-linked (with facilitation of thrombogenic condition)and then into the stable catabolite, D-dimer. These data confirma thrombogenic effect of streptokinase therapy; this tendencycan be limited by prompt use of high doses of heparin.     

Role of technetium-99m planar bone scanning in the evaluation of low back pain

The records of 1018 patients with low back pain in a tertiary spine referral practice were reviewed. One hundred thirty-nine out of 1018 (13.6%) underwent technetium-99m planar bone scanning as part of their investigation. Seventy-three out of 139 scans (52%) showed increased uptake in some area, but only 27 out of 139 (19.4%) showed increased uptake specifically in the low back. Scans consistently yielded no findings with reference to the back when the prescan diagnosis was spinal stenosis, lumbar pain syndrome, herniated nucleus pulposus, or postlaminectomy syndrome. Some scans gave positive findings in patients with a diagnosis of degenerative disc disease, pseudarthrosis, spondylolisthesis, fracture, infection, metabolic disorder, or tumor. Positive scans were generally obtained early after presentation (within 3 months) and negative scans obtained later (after 6 months), suggesting that clinical suspicion is still the main indication for early scanning. Planar bone scanning was helpful in both diagnosis and therapeutic decisionmaking in many conditions.     

骨形态计量学评价低钙对大鼠皮质骨的作用研究

目的 评价低钙饮食对大鼠皮质骨的影响。方法 3月龄SD普通级雄性大鼠40只，随机分为5组。第1、2组饲养1个月，分为正常对照组(1mol，ca1．0％)和极低钙组VLCD(1mol，Ca0．1％)，余下3组饲养3个月，分为正常对照组(3mol，Ca1．0％)、极低钙组VLCD(3mol，Ca0．1％)和低钙组LCD(3mol，Ca0．3％)。各组动物喂养包含对应钙含量的精制饲料，处死前进行双荧光标记。实验结束时，取左侧胫骨中段行骨形态计量学检测。结果 无论是低钙饮食1个月，还是3个月，无论是极度缺钙，还是仅有轻微的钙不足，胫骨中段横截面皮质骨始终未出现显著意义的变化，但骨内膜骨吸收有增加的趋势。结论 低钙对皮质骨作用不明显，这可能与机体在低钙状态下动用骨骼的次序或快慢有关。