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31.
目的 :观察硬膜外腔自动镇痛泵 (AFA)用于剖宫产术后镇痛效果及对产后各项生理指标的影响。方法 :选择剖宫产术后患者 10 0例 ,随机分为两组 ,每组各 5 0例。硬膜外腔自动镇痛泵内含有 0 75 %布比卡因 15ml,0 5 %布比卡因 0 5ml,氟哌啶醇 5mg ,吗啡 8mg ,麻黄素 15mg ,生理盐水 80ml,以每小时 2ml速度给药 ,持续给药 48小时 ,对照组则不给任何药物。采用视觉模拟评分法 ,分别观察 2组患者术后的疼痛情况 ,肠蠕动恢复时间 ,拔尿管后排尿情况 ,产后出血、子宫复旧、泌乳情况及下床活动早晚情况 ,以及是否有恶心、呕吐、呼吸抑制等。结果 :①术后镇痛泵组患者术后无明显疼痛感 ,镇痛效果好 ,而对照组患者术后有明显疼痛感 (P <0 0 1) ;②镇痛泵组患者术后肠蠕动恢复时间为 (16 68±9 3 2 )h ,对照组 (16 2 3± 10 1)h ,两者比较无明显差异 (P >0 0 5 ) ;③术后尿管拔除后尿潴留发生率 ,镇痛泵组 8例 ,对照组 2例 ,差异有显著性 (P <0 0 5 ) ;④镇痛泵组下床活动时间为 (19± 5 )h ,明显早于对照组 (2 7± 8)h ,两组比较差异有显著性 (P <0 0 5 ) ;⑤ 2组患者产后出血、泌乳情况、子宫复旧、术后恶心呕吐、呼吸抑制发生情况比较 ,差异均无显著性(P >0 0 5 )。结论 :硬膜外自动镇痛泵具有良好的镇痛  相似文献   
32.
The inadvertent carryover of amplified fragments of nucleic acids (amplicons) is a potential source of contamination in the polymerase chain reaction. Recently, a method has been developed to generate amplicons with deoxyuracil triphosphate (dUTP) and to specifically hydrolyze these amplicons with uracil-DNA glycosylase (UNG) following the completion of the assay. We evaluated this system for the specific amplification of RNA from coxsackievirus A3 and B3. We found that RNA from both viruses could be amplified with dUTP, although the use of this triphosphate in place of TTP resulted in some loss of assay sensitivity. We also found that the dUTP-containing amplicons could be efficiently hydrolyzed by UNG, resulting in a 10,000,000-fold reduction in amplicon concentration with little effect on the native nucleic acid. The dUTP-UNG method has a great deal of potential for reducing amplicon contamination during the routine performance of nucleic acid amplification reactions.  相似文献   
33.
子宫内膜异位症是育龄妇女的常见疾病 ,近年来其发病率有上升趋势 ,研究认为EM发生发展与腹腔氧化作用有关。氧化作用是一种炎症反应 ,EM中巨噬细胞释放的氧化活性物 ,腹腔液中氧化低密度脂蛋白及其产物的增加 ,子宫内膜细胞氧化酶与抗氧化酶的异常表达 ,腹腔液中VitE的消耗 ,均说明EM与腹腔氧化作用有关。本文综述有关研究结果为用抗氧化剂和抗炎症制剂预防EM发生提供新的研究途径  相似文献   
34.
To estimate the quantitative relation between exposure to respirable silica dust and risk of an attack of silicosis, 1151 workers exposed to silica dust and employed from 1958 to 1987 in a tungsten mine in China were investigated. The results showed that the ratio of respirable silica dust concentration to total silica dust concentration was 0.529. Then, the total silica dust concentration in historical surveillance and monitoring data was converted to respirable silica dust concentration. The free silica content in respirable dust determined by x ray diffraction averaged 24.7%. Multiple logistic regression was used for the dichotomous dependent variables (presence or absence of silicosis). The independent variables in the multiple logistic regression with presence of silicosis as the dependent variable were age when first exposed, tuberculosis (presence or absence), and cumulative exposure to respirable silica dust. The partial regression coefficient of individual cumulative exposure was estimated as 0.079. It implied a positive association between exposure to respirable silica dust and risk of an attack of silicosis. The exposure limit for respirable silica dust was estimated as 0.24 mg/m3 under given conditions.  相似文献   
35.
The effect of exogenous vascular endothelium growth factor (VEGF) on wound healing in an ischaemic skin flap model was evaluated in this study. Seventy-two Sprague-Dawley rats were used. Normal incisional wound and H-shaped double flaps were used as the wound models. The study was divided into two parts. In Part I, VEGF protein levels were determined from the incisional and H-shaped ischaemic wounds at 12 and 24 h, postoperatively. In Part II, tensile strength and immunohistochemical stains were examined to determine the level of microvessel density (MVD) at 1 and 2 weeks, postoperatively in simple incisional wounds, ischaemic wounds, and ischaemic wounds following 1 ml (1 microg/ml) exogenous VEGF injections into the subcutaneous tissue. The results showed a significantly higher level of VEGF protein in the ischaemic wounds than the incisional wounds. Tensile strength was statistically higher in the incisional wound group and in the ischaemic flap wounds with VEGF treatment compared to the ischaemic flaps with no treatment at 1 week, postoperatively (p>0.05). MVD data indicated that ischaemic wound repair with VEGF treatment had significantly higher MVD than the normal incisional wounds and ischaemic wounds without treatment. We conclude that exogenous application of VEGF can increase early angiogenesis and tensile strength in the ischaemic wound.  相似文献   
36.
抗人生长激素免疫血清的制备和鉴定   总被引:1,自引:1,他引:0  
Using small dosage of human growth hormone to immunize rabbit or guinea pig, it is able to induce anti-hGH antibody formation with high titre and high affinity that could be applied to hGH RIA. In the present study five rabbits and three guinea pigs were immunized with 125-200 micrograms and 250-285 micrograms per animal of hGH respectively, followed by boosters of 10-20 or 160-250 micrograms of hGH at 2-4 week intervals for 6 or 3 months. Blood was drown 1-2 weeks before each booster for determination of antibody formation. Antibody titre and affinity were successively observed and specificity of antibody was determined for the final bleeding. It was shown that titres of immune sera from guinea pigs were much higher than those of rabbit immune sera, but vice versa for antibody affinity. This might be due to larger immunogen dose used for guinea pigs than for rabbits. Fourteen different peptide hormones were tested in reference to cross-immunoreactivity to anti-hGH antibody. It could be demonstrated that the major cross-reactive hormones are hFSH and hLH, and hTSH also reacts to rabbit anti-hGH immune sera at a lesser degree. These cross reactivities are obviously owing to the molecular homogeneities between hGH and these hormones especially of their alpha-subunits.  相似文献   
37.
38.
Theoretically, two predominant paths for obtaining more selective anticancer agents may be envisaged. These are: (a) to make compounds which distribute only or preferentially in cancer cells; (b) to make compounds that are able selectively to kill or to differentiate cancer cells. Although in the last two decades research into new anticancer drugs has not produced satisfactory results, there is solid ground on which novel strategies can be developed, mainly based on a much greater biological knowledge of human tumours. This article does not review all the possible approaches that may be followed, but simply discusses some ideas and problems mainly taken from the current research of our laboratory.  相似文献   
39.
本文描述了奇特长唇瓢虫Shiro(?)lla mirol(?)ilis Sasaji的雄性外生殖器与本属两新种:附肢长唇瓢虫Sh.oppe(?)nd(?)a sp.n.,阿里山长唇瓢虫Sh.(?) sp.n.,均产于台湾.种类检索如下:1(2).后基线伸达第一腹板1/2略强:阳基侧叶长,无触须状附肢;鞘翅淡黄棕色,具七个黑色斑纹;体 长1.82 mm………………………………………………………阿里山长唇瓢虫Sh.(?)sp.n.2(1).后基线后缘远超第一腹板长度的1/2;阳基侧叶短,具触须状附肢:3(4).前胸背板棕色,具两个暗棕色模糊斑点;鞘翅棕色,具九个黑斑;体长2.12~2.59 m………… …………………………………………………………………………附肢长唇瓢虫Sh.(?)sp.n.4(3).前胸背板淡黄棕色,无斑点;鞘翅淡黄棕色,具六个黑斑,侧面的一对长形;体长2.00~2.26mm …………………………………………………………………………奇特长唇瓢虫Sh.(?)sasaji  相似文献   
40.
1. The vascular effects of the soluble guanylyl cyclase inhibitor, methylene blue as well as the nitric oxide (NO) synthase inhibitors, NG-nitro-L-arginine (L-NOARG) and diphenyleneiodonium (DPI) were studied in rat isolated aortic rings and conscious, unrestrained rats. 2. Acetylcholine (ACh) and sodium nitroprusside (SNP) caused concentration-dependent relaxation of preconstricted aortic rings. Both methylene blue (1 x 10(-5) M) and L-NOARG (3 x 10(-5) M) abolished ACh-induced relaxation; however, methylene blue but not L-NOARG shifted the concentration-response curve of SNP to the right. 3. In conscious rats, i.v. infusion of methylene blue (1.1 x 10(-5) mol kg-1 min-1), at a concentration which reduced the aortic tissue level of cyclic GMP by 50%, did not significantly alter mean arterial pressure (MAP) and heart rate (HR). In contrast, i.v. bolus injection of L-NOARG (1.5 x 10(-4) mol kg-1) markedly increased MAP and decreased HR. 4. Both ACh and SNP dose-dependently decreased MAP in conscious rats. Methylene blue did not alter the magnitude or duration of ACh- or SNP-induced depressor responses. L-NOARG, on the other hand, significantly though incompletely, reduced the magnitude and duration of the depressor response to ACh but not SNP. The depressor response to ACh or SNP was not altered by pretreatment with indomethacin (1.4 x 10(-5) mol kg-1) or capsaicin (3.3 x 10(-4) mol kg-1). 5. NG-nitro-L-arginine methyl ester (L-NAME) also caused dose-dependent increases in MAP in conscious rats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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