胆道梗阻伴肝动脉血流阻断对肝脏损伤的实验研究

通过检测正常大鼠肝细胞线粒体呼吸功能、ＡＴＰ含量和组织学改变，分别观察肝动脉结扎、胆道梗阻和胆道梗阻伴肝动脉结扎术后肝脏的损伤。结果表明：仅胆道梗阻伴肝动脉结扎组有８３．３３％的大鼠肝细胞出现凝固性坏死。其发生机制是胆道梗阻后门静脉血流量减少，肝脏更加依赖肝动脉血供；另外，肝细胞线粒体呼吸功能抑制和能量代谢紊乱也是肝动脉结扎促成或加重胆道梗阻肝细胞坏死的重要因素。提示对有明显胆道梗阻的病人，行肝动脉结扎或栓塞术应特别慎重。

雌激素对实验性心律失常的影响

静脉注射雌二醇（Ｅ２）６０μｇ／ｋｇ，缩短由乌头碱引起雄大鼠心律失常持续时间，提高哇巴因致雄豚鼠室早、室颤的剂量，降低由氯化钙（ＣａＣｌ２）引起的小鼠死亡率，缩短由肾上腺素诱发雄家兔心律失常持续时间。上述结果提示：雌激素具有抗心律失常作用，可能是通过抑制钠。

超声导引肝内酒精注射并发症发病机理的实验研究

目的：观察酒精注射后产生的不同途径并发症，探讨其病理机制和转归及预防措施。材料与方法：利用２４只家兔在直视下和超声导引下肝内注射无水酒精进行实验研究。结果：酒精主要通过肝内４条途径弥散及经针道外溢，以直接注入较大门脉分支造成弥漫性血管周围纤维化为最严重并发症。结论：拔针前留针３０秒和超声定位下动态观察与少量分次注射，对于减少并发症十分重要。

福尔马林储骨的移植实验

用家兔14只，以桡骨中段10mm骨缺损作为实验模型，右侧植入同种异体福尔马林储骨为实验组，左侧植入酒精储骨作为对照组。于术后2、4、8、10、12周取材，作X线片和普通光镜观察，结果显示：福尔马林储骨移植术后4周缺损区有大量新骨形成，骨质增生活跃。8周时移植骨大部分被新生骨替代。12周时骨缺损基本愈合。结果表明，经福尔马林处理后的同种异体骨有较好的生物相容性，能引导骨生长，从而为推广尸体骨移植的临床应用，简化骨处理步骤提供了实验依据。

门脉高压性胃病发生机制的实验研究

本实验采用二期门静脉结扎法复制大鼠门脉高压模型，测定门脉高压时大鼠胃粘膜血流量，损伤指数以及门脉血中超氧化物化酶，过氧化脂质的变化，并对其胃粘膜超微结构进行观察。结果表明：门脉高压时胃粘膜易受损害，其胃粘膜血流量增多，但在损伤因子作用下，其血流量减少较剧，而门脉血中ＳＯＤ及ＬＰＯ的变化并不显著。超微结构显示：门脉高压时其毛细血管结构的完整性受到破坏。提示门脉高压时胃粘膜在损伤因子作用下血流量减少是门脉高压性胃病发生的重要原因之一，其胃粘膜毛细血管结构的完整性受到破坏可能是血流量急剧减少的病理解剖学基础，而超氧化物歧化酶对自由基的清除作用可能并不参与胃粘膜的保护作用。

Polar residual network model for assisting evaluation on rat myocardial infarction segment in myocardial contrast echocardiography

Objective To investigate the value of polar residual network(PResNet)model for assisting evaluation on rat myocardial infarction(MI)segment in myocardial contrast echocardiography(MCE).Methods Twenty-five male SD rats were randomly divided into MI group(n=15)and sham operation group(n=10).MI models were established in MI group through ligation of the left anterior descending coronary artery using atraumatic suture,while no intervention was given to those in sham operation group after thoracotomy.MCE images of both basal and papillary muscle levels on the short axis section of left ventricles were acquired after 1 week,which were assessed independently by 2 junior and 2 senior ultrasound physicians.The evaluating efficacy of MI segment,the mean interpretation time and the consistency were compared whether under the assistance of PResNet model or not.Results No significant difference of efficacy of evaluation on MI segment was found for senior physicians with or without assistance of PResNet model(both P>0.05).Under the assistance of PResNet model,the efficacy of junior physicians for diagnosing MI segment was significantly improved compared with that without the assistance of PResNet model(both P<0.01),and was comparable to that of senior physicians.Under the assistance of PResNet model,the mean interpretation time of each physician was significantly shorter than that without assistance(all P<0.001),and the consistency between junior physicians and among junior and senior physicians were both moderate(Kappa=0.692,0.542),which became better under the assistance(Kappa=0.763,0.749).Conclusion PResNet could improve the efficacy of junior physicians for evaluation on rat MI segment in MCE images,shorten interpretation time with different aptitudes,also improve the consistency to some extent.

辅酶Q10对供心冷保存的保护作用

目的：探讨供心冷保存中，ＣｏＱ１０作为保存液成分对供心的保护作用，同时探讨在再灌注液中加入ＣｏＱ１０对供心缺血再灌注损害的保护作用．方法：新西兰大白兔２４只分成３组，１组为基础组，２组为对照组，３组为实验组，取心后，１组不保存，２、３组分别在ＵＷ液和ＵＷ＋ＣｏＱ１０液中保存６ｈ，然后在Ｌａｎｇｅｎｄｏｒｆ模型上，１、２组用ＫＨＢ液，３组用ＫＨＢ＋ＣｏＱ１０液再灌注。以功能、代谢和结构多个指标评价供心保存效果。结果：３组各指标优于２组。结论：ＣｏＱ１０作为保存液成分对供心有良好保护作用，在再灌液中加入ＣｏＱ１０对供心缺血再灌注损伤也有良好保护作用。

兔蛛网膜下腔出血后外周血中TNF的变化及其意义探讨

为探讨继发于蛛网膜下腔出血后的迟发性脑血管痉挛的发病机制，采用兔枕大池二次注血法复制蛛网膜下腔出血模型，用经颅多普勒监测脑基底动脉血管痉挛的发生情况，实验前、后分别检测外周血中ＴＮＦ含量。结果显示实验组动物迟发性脑血管痉挛的发生率达８４．６２％，实验第７ｄ外周血中ＴＮＦ含量较实验前升高（Ｐ＜０．０１）。结果表明：在蛛网膜下腔出血后脑血管痉挛的形成中确有免疫因素的参与。

Pharmacokinetics of Scutellarin in Dogs

Aim To establish an RP-HPLC method for the determination of scutellarin in plasma and study its pharmacokinetics in dogs. Methods Scutellarin was given to dogs by intravenous injection and determined by RP-HPLC, the mean plasma concentration-time curve was plotted and pharmacokinetic parameters were calculated by program 3p87. Resu;ts The concentration-time curve of scutellarin could be fitted to three-compartment model with T1/2 pi, T1/2 α and T1/2 β being 1.05 ± 0.80 min, 6.99 + 2.76 min and 51.61 + 28.78 min, respectively, Vc being 880.1 + 508.3 mL, CL being 189.6 + 53.8 mL@ min- 1, and AUC0-90 and AUC0-∞ being 574.43 + 133.95 μg@ min@ mL - 1 and 599.34 ± 132.00μg@ min@mL- 1, respectively. Conclusion The fact that the concentrations of scutellarin in plasma declined rapidly after the medication suggested that the T1/2 of scutellarin should be taken into account in drug administration and preparation development.

Effects of Low Dose Radiation on Tumor Apoptosis, Cell Cycle and Apoptosis-Related Protein Bcl-2 in Tumor-Bearing Mice

To study the effects of low dose radiation (LDR) on tumor apoptosis, cellcycle progression and changes of apoptosis-related protein Bcl-2 in tumor-bearing mice. Methods:Male mice of Kunming strain were implanted subcutaneously with S180 sarcoma cells in the left inguenas an in situ experimental animal model. Seven days later, the mice were subjected to 75 mGywhole-body γ-irradiation. At 24 and 48 h after the irradiation, all mice were sacrificed. The tumorsizes were measured, and tumor cell apoptosis and cell cycle progression were analyzed by flowcytometry. The expression of apoptosis-related protein Bcl-2 and the apoptotic rate of tumor cellswere observed by immunohistochemistry and electron microscopy. Results: Tumors grew significantlyslower after LDR (P 【 0.05). The tumor cells were arrested in G1 phrase and the expression of Bcl-2protein decreased at 24 h. Apoptotic rate of tumor cells was increased significantly at 48 h afterLDR (P 【 0.01). Conclusion: LDR could cause a G1-phase arrest and increase the apoptosis of tumorcells through the low level of apoptosis-related protein bcl-2 in the tumor-bearing mice. Theorganized immune function and anti-tumor ability are markedly increased after LDR. Our studyprovides practical evidence of clinical application to cancer treatment.

Fura－2荧光测定中药有效成分对神经细胞内Ca^（2＋）浓度的变化

将中药有效成分黄芩甙、豆腐果甙、金丝桃甙、熊果酸与大白鼠神经细胞一起进行温育，应用新型钙离子荧光指示剂Ｆｕｒａ－２／ＡＭ测定神经细胞内游离Ｃａ２＋浓度变化。结果表明，上述中药有效成分均能影响胞内Ｃａ２＋释放和胞外Ｃａ２＋内流。

梅山降糖神茶的降血糖作用

将梅山降糖神茶连续４周灌胃给予（ｉｇ）大鼠（３ｇｋｇ－１６ｇｋｇ－１）和小鼠（６ｇｋｇ－１、１２ｇｋｇ－１）后，可显著对抗四氧嘧啶（静脉注射６０ｍｇｋｇ－１）升高大鼠血糖作用；可显著抑制肾上腺素（腹腔注射０．２ｍｇｋｇ－１）和葡萄糖（腹腔注射２ｇｋｇ－１）升高小鼠血糖作用；病理切片结果提示：给药组大鼠胰岛形态。

Establishment of a mdr1 Multidrug Resistant Model of Orthotopic Transplantation of Liver Carcinoma on Nude Mice

To develop a new method of inducing mdrl multidrug resistance by establishinga nude mice model of orthotopic transplantation of liver carcinoma by sporadic abdominalchemotherapy at intervals. Methods: Hepatocellular carcinoma HepG2 cell was cultured and injectedsubcutaneously to form the tumor-supplying mice. The tumor bits from the tumor-supplying mice wereimplanted under the envelope of the mice liver and induced by abdominal chemotherapy withPharmorubicin. Physical examination, ultrasonography, spiral CT and operative inspection were usedto examine tumor progression. RT-PCR and immunohistochemistry were adopted to detect the expressionof mdr1-mRNA and its encoded protein P-gp protein (P-gp). Results: There was no operative dead, therate of implanting tumor successfully was 88% (22/25), the rate of implanting secondly successfullywas 100% (3/3), and the rate of inducing successfully was 80% (16/20). The expression of mdrl-mRNAand the P-gp in the inducing group was 23 folds and 13 folds in the control group respectively.Conclusion: We have established an in vivo model of mdr using nude mice transplanted with orthotopicliver neoplasm coupled to chemotherapy.

兔眼正常前房角小梁网凝集素亲和组化的研究

选用七种对N-乙酰氨基葡萄糖或半乳糖有特异亲和性的凝集素，对16只兔眼正常小梁网进行亲和组化研究。结果证实兔眼正常小梁网细胞外基质和内皮细胞胞浆中，分布有N-乙酰氨基葡萄糖和N-乙酰氨基半乳糖，前者的含量高于后者；ConA对N-乙酰氨基葡萄糖的亲和力比LCA和PSA强，DBA、PNA与PHA、SBA的亲和力相同。

Antitumor effect and mechanism of Gecko on human esophageal carcinoma cell lines in vitro and xenografted sarcoma 180 in Kunming mice

AIM: To investigate the anti-tumor effect of Chinese medicine Gecko on human esophageal carcinoma cell lines and xenografted sarcoma 180 in Kunming mice and its mechanism. METHODS: The serum pharmacological method was used in vitro . The growth rates of the human esophageal carcinoma cells (EC9706 or EC1) were measured by a modifi ed 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The transplanted tumor model of the mouse S180 sarcoma was established. Fifty mice were randomly divided into fi ve groups (n = 10). Three Gecko groups were treated respectively with oral administration of Gecko powder at a daily dose of 13.5 g/kg, 9 g/kg, and 4.5 g/kg. The negative group (NS group) was treated with oral administration of an equal volume of saline and the positive group (CTX group) was treated with 100 mg/kg Cytoxan by intraperitoneal injection at the fi rst day. After 2 wk of treatment, the anti-tumor activity was evaluated by tumor tissue weighing. The impact on immune organ was detected based on the thymus index, spleen index, phagocytic rate and phagocytic index. The protein expression of vascular endothelingrowth factor (VEGF) and basic fibroblast growth factor (bFGF) were detected by immunohistochemistry. The cell apoptotic rate was detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay. RESULTS: The A value in each group treated with Gecko after 72 h was reduced signif icantly in EC9706 and in EC1. The tumor weight in each group of Gecko was decreased signifi cantly (1.087 ± 0.249 vs 2.167 ± 0.592; 1.021 ± 0.288 vs 2.167 ± 0.592; 1.234 ± 0.331 vs 2.167 ± 0.592; P < 0.01, respectively). However, the thymus index and Spleen index of mice in Gecko groups had no significant difference compared with the NS group. The immunoreactive score of VEGF and bFGF protein expression of each Gecko group by immunohistochemical staining were lowered signifi cantly. The apoptosis index (AI) of each group was increased progressively with increase of dose of Gecko by TUNEL. CONCLUSION: Gecko has anti-tumor effects in vitro and in vivo; induction of tumor cell apoptosis and the down-regulation of protein expression of VEGF and bFGF may be contributed to anti-tumor effects of Gecko.

Bone marrow-derived mesenchymal stem cells protect against experimental liver fibrosis in rats

AIM: Recent reports have shown the capacity of mesenchymal stem cells (MSCs) to differentiate into hepatocytes in vitro and in vivo. MSCs administration could repair injured liver, lung, or heart through reducing inflammation, collagen deposition, and remodeling. These results provide a clue to treatment of liver fibrosis. The aim of this study was to investigate the effect of infusion of bone marrow (BM)-derived MSCs on the experimental liver fibrosis in rats. METHODS: MSCs isolated from BM in male Fischer 344 rats were infused to female Wistar rats induced with carbon tetrachloride (CCI4) or dimethylnitrosamine (DMN). There were two random groups on the 42nd d of CCI4: CCl4/MSCs, to infuse a dose of MSCs alone; CCI4/saline, to infuse the same volume of saline as control. There were another three random groups after exposure to DMN: DMN10/MSCs, to infuse the same dose of MSCs on d 10; DMN10/saline, to infuse the same volume of saline on d 10; DMN20/MSCs, to infuse the same dose of MSCs on d 20. The morphological and behavioral changes of rats were monitored everyday. After 4-6 wk of MSCs administration, all rats were killed and fibrosis index were assessed by histopathology and radioimmunoassay. Smooth muscle alpha-actin (alpha-SMA) of liver were tested by immunohistochemistry and quantified by IBAS 2.5 software. Male rats sex determination region on the Y chromosome (sry) gene were explored by PCR. RESULTS: Compared to controls, infusion of MSCs reduced the mortality rates of incidence in CCl4-induced model (10% vs 20%) and in DMN-induced model (20-40% vs 90%).The amount of collagen deposition and alpha-SMA staining was about 40-50% lower in liver of rats with MSCs than that of rats without MSCs. The similar results were observed in fibrosis index. And the effect of the inhibition of fibrogenesis was greater in DMN10/MSCs than in DMN20/MSCs. The sry gene was positive in the liver of rats with MSCs treatment by PCR. CONCLUSION: MSCs treatment can protect against experimental liver fibrosis in CCMnduced or DMN-induced rats and the mechanisms of the anti-fibrosis by MSCs will be studied further.

Presence and integration of HBV DNA in mouse oocytes

AIM: Hepatitis B is a worldwide public health problem. To explore the feasibility of hepatitis B virus (HBV) vertical transmission via oocytes, the presence and integration of HBV DNA in mouse oocytes were studied. METHODS: Genomic DNA was isolated and metaphases were prepared, respectively from mouse oocytes cocultured with pBR322-HBV DNA plasmids. PCR, Southern blot, dot hybridization and fluorescence in situ hybridization (FISH) were performed to explore the existence and integration of HBV DNA in oocytes.RESULTS: PCR detected positive bands in the tested samples, and then Southern blot revealed clear hybridization signals in PCR products. Final washing solutions were collected for dot hybridization and no signal for HBV DNA was observed, which excluded the possibility that contamination of washing solutions gave rise to positive results of PCR and Southern blot. FISH demonstrated that 36 of 1 000 metaphases presented positive signals. CONCLUSION: HBV DNA sequences are able to pass through the zona and oolemma to enter into oocytes and tointegrate into their chromosomes. HBV DNA sequences might be brought into embryo via oocytes as vectors when they are fertilized with normal spermatozoa.

Effects of rhubarb on isolated gastric muscle strips of guinea pigs

AIM:To study the effects of rhubarb (dried root of Rheum officinale Baill.) on contractile activity of isolated gastric muscle strips of guinea pigs and its possible mechanism. METHODS: A total of 48 guinea pigs were killed to remove the whole stomach. Then, the stomach was opened and the mucosal layer was removed. Parallel to the circular fibers, muscle strips were cut from the body. Each isolated gastric muscle strip was suspended in a tissue chamber containing 5 mL Krebs solution, constantly warmed by water jacket at 37℃ and bubbled continuously with a mixed gas of 950 mL/L O2 and 50 mL/L CO2. After being incubated for 1 h with 1 g tension, rhubarb of varied concentrations (1%, 2%, 7%, 20% and 70%) was added cumulatively into the tissue chamber at intervals of 2 min. Atropine (10-6 mol/L) or isoptin (5x10-8 mol/L) or hexamethonium (10-5 mol/L) was given 2 min before the administration of rhubarb. The isometrical response was measured with an ink-writing recorder. RESULTS: Rhubarb dose dependently increased the resting tension of gastric body circular muscle (CM) (r = 0.726, P<0.05). Atropine (r= 0.829, A:0.05), isoptin (r= 0.764, A;0.05) and hexamethonium (r = 0.797, P<0.05) did not affect its action in a dose-related manner. Atropine apparently reduced the increasing action of 1%, 3%, 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Isoptin inhibited the effect of 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Hexamethonium reduced the increasing action of 1%, 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Rhubarb increased the contractile frequency of CM of body. While atropine, isoptin and hexamethonium did not inhibit the contractile frequency of gastric body CM in comparison with rhubarb at the same concentration, rhubarb at the highest concentration (100%) decreased the mean contractile amplitude of gastric body CM. Atropine, isoptin and hexamethonium did not affect the mean contractile amplitude of gastric body CM compared to rhubarb at the same concentration. CONCLUSION: Rhubarb has exciting actions on isolated gastric smooth muscle strips of guinea pig. The exciting action of rhubarb is partly mediated via cholinergic M receptor, cholinergic N receptor and L-type calcium channel.

Effect of emodin on small intestinal peristalsis of mice and relevant mechanism

AIM: To investigate the effect of emodin on small intestinal peristalsis of mice and to explore its relevant mechanisms.METHODS: The effect of emodin on small intestinal peristalsis of mice was observed by charcoal powder propelling test of small intestine. The contents of motilin and somatostatin in small intestine of mice were determinated by radioimmunoassay. The electrical potential difference (PD) related to Na+ and glucose transport was measured across the wall of reverted intestinal sacs. Na+-K+-ATPase activity of small intestinal mucosa was measured by spectroscopic analysis.RESULTS: Different dosages of emodin can improve small intestinal peristalsis of mice. Emodin increased the content of motilin, while reduced the content of somatostatin in small intestine of mice significantly. Emodin 0.2, 0.4, 0.8, and 1.6 g/L decreased PD when there was glucose. However, emodin had little effect when glucose was free. The Na+-K+-ATPase activity of small intestinal mucosa of mice in emodin groups was inhibited obviously. CONCLUSION: Emodin can enhance the function of small intestinal peristalsis of mice by mechanisms of promoting secretion of motilin, lowering the content of somatostatin and inhibiting Na+-K+-ATPase activity of small intestinal mucosa.