Short-Term Toxicity of Bitumen Upgrading Products in the Rat Following Repeated Dermal Exposure

Light gas oil (B-LGO), heavy gas oil No. 1 (B-HGOI), and heavygas oil No. 2 (B-HGOII) fractions of bitumen upgrading products(BUPs) were applied on the dorsal skin of rats at 25 mg/kg bw/day(low dose), 100 mg/kg bw/day (intermediate dose), and 400 mg/kgbw/day (high dose) for 4 weeks. Control animals received normalsaline while positive controls received a medium boiling coalliquefaction product (CLP) at 100 and 400 mg/kg bw/day. Reducedfood consumption and growth suppression were observed in malesand females treated with B-HGOI, B-HGOII, and CLP, but onlyin males receiving B-LGO. Increased relative spleen, kidney,and liver weights were observed in animals treated with B-HGOI,B-HGOII, and CLP, but not in control or LGO groups. A dose-relatedincrease in absolute and relative liver weight was most markedin animals receiving B-HGOII where a significant increase wasobserved starting at the low dose, followed by those receivingB-HGOI and CLP. Appearance of pale foci on the splenic capsuleand increases in spleen/body weight ratio were limited to animalsreceiving B-HGOI and B-HGOII. Decreases in hematocrit and RBCand increase in percentage of reticulocytes were observed inanimals of both sexes receiving B-HGOI and B-HGOII. Female ratsappeared to be more severely affected because significant decreasesin hemoglobin and RBC were observed in animals receiving thelow dose of B-HGOII and the intermediate dose of B-HGO-I. Increasedserum cholesterol was observed in B-HGOII-treated females atall dose levels, and in males starting at the intermediate dose.Histological changes were observed in the thymus gland, wheremoderate to marked cortical atrophy was noted in male and femalerats receiving the high dose of B-HGOI and B-HGOII, and in thebone marrow, where the most significant abnormality was thepresence of focal myelofibrosis in some male rats treated withB-HGOI and B-HGOII. Mild to moderate histological changes werefound in the thyroid, liver, and spleen of rats of all treatmentgroups. Changes in the skin included moderate hyperkeratosisin fe males receiving high doses of B-LGO and in animals ofboth sexes receiving high doses of B-HGOI, and moderate to markedepidermal hyperplasia in rats receiving high doses of B-HGOI.Based on these multiple endpoints, the severity of systemictox icity was B-HGOII > B-HGOI > CLP B-LGO. The NOEL wasabout 25 mg/kg bw/day for B-LGO and lower than 25 mg/ kg bw/dayfor B-HGOI and B-HGOII.     

Subchronic Toxicity of 3,3',4,4',5-Pentachlorobiphenyl in the Rat: I. Clinical, Biochemical, Hematological, and Histopathological Changes

The systemic, toxicity of 3,3',4,4',5-pentachlorobiphenyl (PCB126) following subchronic dietary exposure was investigatedin Sprague-Dawley rats. PCB 126 was administered to rats ofboth sexes at concentrations of 0.1, 1.0, 10, or 100 ppb intheir diet for 13 weeks. Another group of rats received a loadingdose of 5 µg PCB/kg body wt at the start of the feedingperiod followed by exposure to 10 ppb PCB diet for the sameperiod of time as the other groups. Growth suppression and decreasedfood consumption were observed in the highest dose groups ofboth sexes. Increased organ/body weight ratios for the liveroccurred in the 10 and 100 ppb groups of both sexes. Rats ofboth sexes exposed to the highest dose of the PCB also exhibitedincreased relative kidney, spleen, and brain weights. Hematologicaland most serum biochemical changes were confined to the 100ppb groups. These included elevated alkaline phosphatase, bilirubin,cholesterol, and aspartate aminotransferase, and decreased serumglucose, hemoglobin, erythrocytes, hematocrit, and platelets.A dose-dependent increase in liver ethoxyre-sorufin-O-deethylaseactivity was observed in rats of both sexes starting at 0.1ppb. A dose-dependent increase in liver uroporphyrin levelswas observed in both sexes and significant changes occurredin the female rats at 1.0 ppb and higher dose groups. Decreasedliver vitamin A was observed in the 10 ppb group and higherin both sexes. Kidney vitamin A was elevated in the 100 ppbgroup. No statistically significant changes were noted in concentrationsof brain biogenic amines. PCB 126 residues were 10-fold higherin liver than in fat. Treatment-related histopathological changeswere observed in the thymus, thyroid, bone marrow, and liverof rats exposed to the 10 ppb diet, but increased frequencyof mild changes was observed in most of these tissues at the1.0 ppb level. Based on the above data, the no adverse effectlevel was judged to be 0.1 ppb in the diet or 0.01 µg/kgbody wt/day.     

高度近视眼白内障手术疗效观察

目的　分析高度近视眼白内障手术效果。方法　高度近视合并白内障病例共１９１ 例（２７９ 只眼）,行白内障术后３ｍｏ以上,随访视力、眼屈光度及并发症,计算测量误差及ＳＲＫ－ＩＩ公式误差。结果　术后矫正视力０ ．５ 者２００ 只眼,占７１．７ ％ ;矫正视力＜ ０．１ 者１３ 只眼,占４ ．７ ％ － 眼轴越长,近视性眼底病变越重。术后发生视网膜脱离２ 只眼（０ ．７％） 。眼轴长度测量误差值平均为０．５３ｍｍ ,ＳＲＫ－ＩＩ公式计算的平均绝对屈光误差值为１．１２Ｄ。结论　高度近视眼白内障手术效果较一般人群差,且眼轴越长效果越差。     

小剂量尿激酶与低分子肝素钙治疗不稳定性心绞痛

目的观察小剂量尿激酶+低分子肝素钙治疗不稳定性心绞痛(UAP)的临床疗效。方法将80例UAP患者随机分为尿激酶、低分子肝素钙组(A组)43例,尿激酶10万U溶于100ml生理盐水静脉滴注,连续12d,低分子肝素钙5000U皮下注射,1次/d,共12d;常规治疗组(B组)37例,硝酸甘油10mg溶于5%葡萄糖500ml静脉滴注,共12d,复方丹参20ml溶于5%葡萄糖200ml静脉滴注,共12d。观察两组治疗UAP总有效率及出血等不良反应的发生率,治疗前后测定血小板计数(BPC)、激活全血凝固时间(ACT)、纤维蛋白原定量(FB)。结果两组UAP治疗总有效率分别为88.4%和62.2%(P<0.05),轻微出血发生率两组间及治疗前后BPC、ACT、FB均无显著性差异(P>0.05)。结论小剂量尿激酶+低分子肝素钙治疗UAP疗效显著,且用药安全。     

甘糖酯对实验糖尿病大鼠粘附分子-CD54、CD106、CD62p的影响

目的观察糖尿病大鼠肾脏、主动脉等粘附分子的变化及甘糖酯干预的影响,为早期防治糖尿病并发症提供科学依据.方法实验分正常对照、糖尿病对照、高、低剂量甘糖酯共4组,通过免疫组织化学方法观察大鼠肾脏和主动脉CD54和/或CD106的表达,应用流式细胞仪测定血中单个核细胞表面CD54、血小板表面CI)62p的表达水平;应用甘糖酯治疗8周后,观察上述指标的变化.结果(1)血单个核细胞表面CD54测定表明高剂量甘糖酯组有明显降低,(CD54高=36.04±11.01%,VS CD54DM=65.09±14.92%,P＜0.05),而低剂量甘糖酯组降低不明显;甘糖酯时血小板表面CD62P表达影响不大;(2)肾脏和主动脉CD54、CD106免疫组化显示甘糖酯能降低其表达并减轻组织病理变化,且与剂量有关.(3)甘糖酯有降低血糖的作用,并与剂量有关(高剂量组BG治疗前=20.93土4.22mmol@L-1,BG治疗后=15.76±2.39mmol@L-1,P＜0.05;低剂量组BG治疗前=17.35±1.13mm0l@L-1,BG治疗后=13.52±6.24mmol@L-1,P＞0.05).结论糖尿病粘附分子的增加可能是糖尿病肾病和大血管病变的重要发病因素,甘糖酯可降低CD54、CD106对糖尿病并发症有延缓和改善作用.     

藻酸双酯钠注射液细菌内毒素检测

目的:建立藻酸双酯钠注射液的细菌内毒素检查法。方法:参照中国药典2000年版二部细菌内毒素检查法要求进行试验。结果:该药在 0.125g·L~(-1)下无干扰作用。结论:该药采用内毒素检查法进行检查是可行的。     

反相高效液相色谱法测定发酵液中梅岭霉素

目的:建立了发酵液中梅岭霉素的定量测定方法。方法:反相高效液相色谱法,Hypersil-C_(18)柱(4 mm×125mm,5μm),流动相为乙腈-水(78:22),流速1.2mL·min~(-1),检测波长238 nm,室温测定。结果:在1O.2～163.2μg·mL~(-1)范围内梅岭霉素浓度与峰面积呈良好线性关系,r=0.999 7,回归方程为Y=25.44X+2.72。样品的日间 RSD≤1.8％,高中低浓度样品的日内RSD≤2.5％(n=8)。平均回收率为96.9％(n=8,RSD<3.0％)。结论:本方法快速、准确、简便、稳定,为定量分析提供了可靠的依据。     

肾上腺素诱导兔血小板聚集的实践与理论探讨

目的创建以Ａｄｒ诱导兔血小板聚集的方法，并对受体分子特性作初步探讨。方法以高Ｋ＋缓冲液等取代兔ＰＲＰ中血浆，以Ａｄｒ诱导聚集，以Ａｐｙｒ证实结果。结果兔血小板悬浮于高Ｋ＋缓冲液时Ａｄｒ能单独诱导真正的聚集。结论由此推测血小板膜上α２肾上腺素受体分子可能为由两种亚单位组成：促聚亚单位和辅助亚单位。人辅助亚单位当Ａｄｒ浓度高达聚集阈值以上时可被激活，与促聚亚单位结合为活性的二聚体，与Ａｄｒ进一步结合发生聚集作用。兔辅助亚单位则还需要高Ｋ＋方能被激活     

γ1neo-hgp100基因的体外转染表达及体内免疫保护效应

肿瘤转移是一个复杂的、多步骤的、肿瘤细胞和宿主细胞相互作用的过程，是恶性肿瘤的重要生物学行为，往往是导致病人死亡的直接原因。随着分子生物学的发展，对肿瘤转移抑制的研究已进入分子水平，nm23基因即是近年来发现并被证实与多种肿瘤的转移有关的较新的肿瘤抑制基因，该基因可能通过影响细胞内微管的聚合／解聚和G蛋白介导的信号传导，而参与肿瘤的发生和发展。