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991.
吴强  卫煊 《眼科研究》1999,17(3):183-185
目的 从基因转录水平确定人视网膜色素上皮(RPE)细胞是否具有合成纤溶酶原激活物抑制-1(PAI-1)蛋白酶的生物学特性。方法 取供体人眼RPE细胞进行体外培养,当细胞生长融合岳取RNA,应用Nothernblot分析技术,经特异3的探针对人RPE细胞总RNA进行检测。结果 在体外培养的RPE细胞基因转录产生中存在PAI-1mRNA的表达,其长度分别为3.0kb和2.3kb,结论 人RPE细胞能够  相似文献   
992.
3 124例各类斜视手术的分布调查   总被引:4,自引:2,他引:2  
卢炜 《眼科》1999,8(4):209-210
目的:了解临床各类斜视手术的分布情况,以掌握最常见斜视手术分布数据。方法:3年3124例斜视手术资料的统计分析。结果:共同性斜视的手术2629例占84.2%。麻痹性斜视的手术495例占15.8%。共同性外科视的手术1779例占67.7%。先天性麻痹性斜视手术中先天性上斜肌麻痹手术量占第一位。后天性麻痹性斜视手术中外直肌麻痹手术量占第一位。结论:最常见的斜视手术是共同性斜视。共同性外斜视的手术量最大  相似文献   
993.
994.
宋诗铎  张同海 《天津医药》1999,27(10):602-604
目的:为获得与天然鲑鱼生长激素一致的基因工程产物,对已构建的鲑鱼生长激素基因分泌型表达质粒pOsGH153进行改造,删除所编码表达产物氨基端多余的9个碱基,方法:采用PALTER系统进行寡聚核苷酸指导下的基因定点缺失突变。突变质粒pOsGH158经限制性酶切图谱及Southern印迹杂交分析加以证,结果:含有表达质粒pOsGH158的大肠杆菌株经IPTG诱导后提取周质帽白,经SDS-PAGE及免疫  相似文献   
995.
Several microbes were isolated from the contaminated fuel-oil in Taiwan and the microbial corrosion of aluminum alloy A356-T6 was tested by MIL-STD-810E test method. Penicillium sp. AM-F5 and Cladosporium resinac ATCC 22712 had significant adsorption and pitting on the surface of aluminum alloy, Pseudomonas acruginosa AM-B5 had weak adsorption and some precipitation in the bottom, and Candida sp. AM-Y1 had the less adsorption and few cavities formation on the surface. pH of the aqueous phase decreased 0.3 to 0.7 unit for 4 months of incubation. The corrosion of aluminum alloy was very significant in the cultures of Penicillium sp. AM-F2, Penicillium sp. AM-F5 and C. resinac ATCC 22712. The major metabolites in the aqueous phase with the inoculation of C. resinac were citric acid and oxalic acid, while succinic acid and fumaric acid were the minors.  相似文献   
996.
The contents of 10 minor and trace elements in histologically confirmed gastric adenocarcinomas and their corresponding normal gastric mucosal tissues obtained from 39 patients at the time of gastric resection were simultaneously determined by instrumental neutron activation analysis. Specimens were irradiated by reactor neutrons and subsequently subject to direct analysis using a high-resolution HPGe -spectrometer. Univariate analysis revealed that gastric cancer tissues had significantly higher concentrations of Fe, K, Mg, Na, Rb, Se, and Zn than normal gastric mucosal tissues. However, multivariate analysis found that Fe, K, and Se were independent elements that associated with gastric cancer. Upon further evaluation of their clinical significance, we found a high tissue K level was related to lymphatic duct metastasis. High Se tissue levels were linked to intestinal type adenocarcinoma. A positive correlation was found between high Fe levels and vascular involvement. These findings suggest that Fe and K are associated with gastric cancer progression. Se is involved in carcinogenesis of stomach in high-risk areas. The mechanisms that underlie the corresponding pathohistological features deserve further study.  相似文献   
997.
Summary The human saphenous vein was used to examine whether presynaptic histamine receptors can modulate noradrenaline release and, if so, to determine their pharmacological characteristics. Strips of this blood vessel were incubated with [3H]noradrenaline and subsequently superfused with physiological salt solution containing desipramine and corticosterone. Electrically (2 Hz) evoked 3H overflow was inhibited by histamine and the H3 receptor agonist R-(–)--methylhistamine. Histamine-induced inhibition of electrically evoked tritium overflow was not affected by 2-adrenoceptor blockade by rauwolscine. S-(+)--methylhistamine (up to 10 mol/l) as well as the histamine H1 and H2 receptor agonists 2-(2-thiazolyl)ethylamine (up to 3 mol/l) and dimaprit (up to 30 mol/l), respectively, were ineffective. The selective histamine H3 receptor antagonist thioperamide abolished the inhibitory effect of histamine. The histamine H2 and H1 receptor antagonists ranitidine and pheniramine, respectively, did not affect the histamine-induced inhibition of evoked tritium overflow. The present results are compatible with the suggestion that the sympathetic nerves of the human saphenous vein are endowed with inhibitory presynaptic histamine receptors of the H3 class. Send offprint requests to M. Gothert at the above address  相似文献   
998.
Several factors can be involved in evaluating a motion analysis system. The purposes of this study were to evaluate: 1) the accuracy, repeatability, and linearity of the Skeletal Analysis System (Metrecom System) and 2) the reliability of bony landmark identification with a method using the Metrecom Skeletal Analysis System (Metrecom Method) to obtain coordinates for human skeletal landmarks. A calibration control object with 20 known three-dimensional coordinates in a rectangular field was used as the gold standard for evaluating the Metrecom System for measuring X, Y, and Z spatial coordinates. The Metrecom Method was then evaluated using a test-retest approach for 10 bony landmarks on each of 10 normal subjects examined by two different examiners. Relative to the Metrecom System, the results demonstrated that the hysteresis was minimal (1.8 mm), and linearity was excellent. The differences between the true and measured distances for the 20 known points were not statistically significant (p >/= .05). The variability for any point within the field of measurement was homogeneous (p /= .05). The mean intrarater reliability (ICC) for identification of coordinates for 10 bony landmarks was .95 for one examiner and .96 for the other examiner. The mean interrater ICC was .87, with all coefficients being above .80. In conclusion, use of the Metrecom System is affected by controllable human factors, in which case valid and reliable measurements for skeletal landmarks can be obtained. J Orthop Sports Phys Ther 1992;16(4):182-188.  相似文献   
999.
1000.
Since the rapid development of microsurgery it is feasible to replant most severed thumbs and digits. In certain patients, however, the trauma is so severe that replantation cannot be performed, such as crush or burst injuries where the amputated part is badly smashed or broken into pieces. There are many methods used to reconstruct amputated thumbs or digits. In our hospital reconstruction of the thumb is accomplished by second toe transplantation, nail flap of the great toe transplantation and bone graft, and nail flap of the great toe and skeleton from the second toe transplantation. Reconstruction of fingers is undertaken through second toe transplantation and second and third toe transplantation. After total loss of the hand, double second toe transplant is used for reconstruction.
Resumen Gracias al rápido desarrollo de la microcirugía, actualmente es factible reimplantar la mayor parte de los pulgares y los dedos de la mano que hay an sido amputados. Sin embargo, en ciertos pacientes el trauma es tan severo que la reimplantación no puede ser realizada, tal como ocurre con las lesiones por aplastamiento o por explosión, donde la parte amputada resulta severamente aplastada o fragmentada en pedazos. Existen muchos métodos de reconstrucción; los siguientes son los utilizados en nuestro hospital.

Résumé En raison du développement rapide de la microchirurgie, il est possible de réimplanter la plupart des doigts amputés. Chez certains patients, cependant, le traumatisme est tellement important qu'aucune réimplantation ne peut être tentée: dans les accidents par écrasement ou les lésions par souffle dans lesquelles la partie amputée est abîmée ou fracasée. Il existe de nombreuses méthodes pour reconstruire un pouce ou un doigt. Les procédés que nous employons dans notre Hôpital sont: (1) pour le pouce, le transfert du deuxième orteil, le lambeau unguéal du gros orteil avec greffon osseux, le lambeau unguéal et le transfert osseux du deuxième orteil; (2) pour les autres doigts, le transfert du deuxième orteil, seul ou combiné avec celui du troisième; (3) pour la main, le transfert bi ou unilatéral du deuxième orteil; et (4) des prothèses de main à visée esthétique.
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