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61.
Summary In order to investigate possible effects of smoking and drinking on the metabolism of toluence in occupational settings, 206 toluene-exposed men (mean age: 31.4 years) in shoemaking, painting, or surface-coating workshops together with 246 nonexposed control men (36.8 years) were studied for the time-weighted average intensities of exposure to toluene, hippuric acid concentration in shift-end urine samples, and the two social habits of smoking and drinking. The mean daily consumptions of cigarettes and ethanol were about 20 pieces and 10 g among smokers and drinkers, respectively. The geometric mean toluene concentration among the exposed subjects was about 20 ppm, with a maximum of 521 ppm. Regression analysis after classification of the subjects by smoking and drinking clearly demonstrated that the two social habits, when combined, markedly reduce the hippuric acid level in the urine of workers exposed to was a significant association between smoking and drinking habits, which hindered separate evaluation of the effects of the two habits on toluene metabolism. Comparison of the present results with the findings reported in the literature, however, suggested that the observed effects may be attributable to smoking rather than to drinking habits.  相似文献   
62.
应用原位杂交技术,观察了二乙基亚硝胺(DEN)诱发大鼠肝癌前病变组织中胎盘型谷胱甘肽S转移酶(GST-P)mRNA的表达。结果显示,GST-PmRNA主要在癌前病变肝组织中的变异灶及灶外卵圆形细胞内表达,且在变异灶间或和同一灶内阳性细胞间表达程度不尽一致,而正常肝、再生肝组织中未见其表达。提示在分子水平上变异灶细胞及卵圆型细胞可能成为实验性肝癌的癌前期细胞  相似文献   
63.
For the past 10 years the alfa-hydroxyacids and the bovine collagen injection have been used for peeling and the correction of multiple skin diseases. Until now, such progressive achievement has occurred in separate parallels just like the indications that have been held distinct. However, the studies carried out in order to clarify the mechanical action of the two substances have shown a common and fundamental denominator: the stimulation of synthesis of the new collagen in the patient's skin. On the basis of these results and the existence of common clinical indications of the use of glycolic acid and collagen, the authors have worked out a protocol involving a combined and contemporary application in progressive steps. They developed the rationales of such protocol and analyzed the results of its application on a number of carefully selected patients for a clinical comparison and on a sample of rats for a histological comparison. They have concluded that the contemporary use of glycolic acid and bovine collagen is a simple and safe method whose synergy action leads to more intense and long-lasting effects than the ones observed in the isolated application of the two substances. The authors have also obtained interesting and significant histological results.  相似文献   
64.
65.
BACKGROUND: In Europe, several filler devices are currently on the market for use in aesthetic dermatology and some of them cause severe, permanent, adverse reactions. Since 1996 a non-animal stabilized hyaluronic acid (NASHA) from Q-Medical, Sweden, has been introduced and is becoming a leading product in aesthetic dermatology. Hyaluronic acid has no species specificity and skin testing is not recommended before treatment. OBJECTIVE: Our purpose was to evaluate the incidence of adverse reactions from 1997 to 2001 and the safety of NASHA after injections into the skin for aesthetic reasons. METHOD: Surveys were sent to physicians in European countries that agreed to participate. This is a retrospective study. A total of 12 344 syringes were sold by the Q-Medical to these physicians and we evaluated the total number of patients treated to 35% of this number (4320). We separated immediate hypersensitivity reactions from delayed reactions and analysed infectious and other types of reactions. RESULTS: From 1997 until 2001, 34 cases of hypersensitivity were reported: 16 cases of immediate hypersensitivity and 18 cases of delayed. The global risk of sensitivity is 0.8%. Since 2000, the amount of protein in the raw product has decreased and the incidence of hypersensitivity reactions is around 0.6%. As 50% of these reactions are immediate and resolved within less than 3 weeks, the risk of strong but transient, delayed reaction is around 0.3%. Four cases of abscess were reported. They were all sterile. No bacterial infection was found. Herpetic recurrence is possible after lip augmentation according to the technique of injection. No systemic reactions were reported. CONCLUSION: NASHA is a very useful and safe filler product. Skin testing does not seem to be necessary.  相似文献   
66.
The effect of the barbiturate T2000 (1,3-dimethoxymethyl-5,5-diphenyl-barbituric acid; DMMDPB) on essential tremor, given in twice daily doses of 400 and 300 mg, was assessed in two brief, randomized, placebo-controlled, parallel-group, double-blinded, single-center trials in 12 and 22 patients, respectively. These trials represent the first clinical use of T2000 for a specific indication. The primary endpoint was the change in the mean scores of the treated and control groups based on the Fahn-Tolosa-Marin tremor scale. In the first study of 12 patients treated with 400 mg or placebo twice daily for 14 days, the mean change from baseline at day 14 was 19.3 (P < 0.0001) in the treated group and 9.0 (P = 0.0121) in the control group. Using a two-factor mixed ANOVA model to evaluate within group and between group changes, the effect of T2000 was significantly different from that of the placebo group (P = 0.03). In the second study of 22 patients treated with 300 mg of T2000 or placebo twice daily for 20 days, statistically significant changes were seen in treated patients compared to baseline, but the ANOVA model did not demonstrate a significant treatment effect of T2000 compared to placebo. When the treated groups from each study are compared, the 800-mg daily group is significantly different from the 600-mg daily group (P = 0.02). Some treated patients in each study, but no placebo patients, experienced marked improvement. These results support further evaluation of T2000 in the treatment of essential tremor.  相似文献   
67.
目的建立一种操作简便、高效的测定脑组织中去甲肾上腺素(NA)、肾上腺素(AD)、多巴胺(DA)、3,4二羟基苯乙酸(DOPAC)及高香草酸(HVA)的方法,为有关药物作用机理的研究提供实验手段.方法以有机溶剂提取,高效液相色谱--电化学检测器(HPLC-EC)测定大鼠纹状体、皮质、下丘脑NA、AD、DA、DOPAC及HVA的含量.结果测得NA、AD、DA、DOPAC及HVA的绝对回收率依次分别为:80.3%±12.4%,86.5%±14.3%,90.3%±12.1%,89.5%±17.2%、87.6%±[13].2%.线性范围0.2~20ng,批内与批间变异系数分别小于8%及10%.结论该方法具有简便、迅速、回收率较高的特点,便于实验室应用.  相似文献   
68.
目的研究肝癌病例癌组织、癌旁组织及非癌肝组织中HOXA9 mRNA的表达及其临床意义.方法标本经10%中性福尔马林固定后常规制作石蜡包埋切片,HOXA9 mRNA行原位杂交检测.结果临床分析发现术后血清AFP值、AFU值、Glo值、PAB值及SHCSP阳性率均有明显减少.癌组织HOXA9mRNA阳性表达评分(1.94±1.69)明显低于非癌肝组织(3.17±1.70),两者有显著差异;癌旁组织HOXA9mRNA阳性表达评分(2.54±1.20)与非癌肝组织及癌组织无显著差异.癌组织、癌旁组织及非癌肝组织三者HOXA9mRNA阳性表达率(54.84%、76.92%、83.33%)无显著差异.除HCC中HOXA9RNA阳性表达评分(1.81±1.78)显著低于MHC(2.75±0.50)外,HOXA9mRNA表达阳性率及阳性评分与癌分化程度、AFP值、SHCSP是否阳性、AFU值、肝硬化有无、转移情况、有无癌栓、大体形态及肿块最大径等临床病理特征均无明显关系.结论本研究结果显示HOXA9mRNA可能与肝癌的发生有密切关系.临床上检测HOXA9mRNA的表达情况对肝癌的早期发现和早期诊断可能有较重要的临床意义,值得深入研究.  相似文献   
69.
Summary: To develop a method for identification of differential gene expression between different cell populations, several convenient techniques of molecular biology, including subtractive hybridization, suppression PCR, T/A cloning and sequencing, were used to identify genes expressed differentially in CD45^- and CD45^- cells isolated from U266 cell line of multiple myeloma. Our results showed that the levels of abundant genes scale down 20 times through subtractive hybridization.Plasmid DNA from CD45^- cell clones was hybridized with forward or backward cDNA probes synthesized from CD45^- and CD45 cells, respectively. A few of differentially expressed genes reconfirmed by RT-PCR were identified from 500 expressed clones of CD45^- cells. It is concluded that a strategy for gene expression identification developed from conventional molecular biological methods can be used in different laboratories.  相似文献   
70.
蜂毒素微球经动脉介入治疗大鼠肝癌的实验研究   总被引:9,自引:0,他引:9  
目的:观察蜂毒素微球(M-MS)经动脉介入对大鼠肝癌的治疗作用.方法:采用改良的复乳-液中干燥法制备蜂毒素-聚乳酸/羟乙酸微球,建立大鼠移植性肝癌模型并随机分为四组,分别经肝动脉灌注生理盐水(NS,1.5ml/kg)、蜂毒素(Melittin,0.35mg/kg)、空白微球(B-MS,10mg/kg)和蜂毒素-聚乳酸/羟乙酸微球(10mg/kg).比较治疗后各组大鼠的肿瘤生长情况、肿瘤坏死程度和生存时间.结果:与生理盐水组比较,Melittin组、B-MS组肿瘤生长受到明显抑制(P<0.01),肿瘤坏死程度以轻中度为主,但两组动物生存时间均未能明显延长(P>0.05).M-MS组与NS组、Melittin组及B-MS组相比,肿瘤生长抑制显著(P<0.01),肿瘤坏死更广泛、更彻底,且经蜂毒素微球治疗的大鼠生存期显著延长(P<0.01).结论:蜂毒素以药物微球的剂型经肝动脉给药,抗肿瘤效果明显优于单纯的蜂毒素和空白微球.  相似文献   
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