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991.
T M Williams J M Bergman K Brashear M J Breslin C J Dinsmore J H Hutchinson S C MacTough C A Stump D D Wei C B Zartman M J Bogusky J C Culberson C Buser-Doepner J Davide I B Greenberg K A Hamilton K S Koblan N E Kohl D Liu R B Lobell S D Mosser T J O'Neill E Rands M D Schaber J R Huff 《Journal of medicinal chemistry》1999,42(19):3779-3784
992.
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
993.
Yang SS Chen CY Wei CB Lin YT 《Zhonghua Minguo wei sheng wu ji mian yi xue za zhi = Chinese journal of microbiology and immunology》1996,29(4):185-196
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
994.
Tissue potassium,selenium, and iron levels associated with gastric cancer progression 总被引:4,自引:0,他引:4
Chew-Wun Wu MD Yuan-Yaw Wei BS Chin-Wen Chi PhD Wing-Yiu Lui MD Fang-Ku P'eng MD Chien Chung PhD 《Digestive diseases and sciences》1996,41(1):119-125
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
995.
G. J. Molderings G. Weißenborn E. Schlicker J. Likungu M. Göthert 《Naunyn-Schmiedeberg's archives of pharmacology》1992,346(1):46-50
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
996.
Smidt GL McQuade KJ Wei SH 《The Journal of orthopaedic and sports physical therapy》1992,16(4):182-188
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 accuracy (average difference between known and measured points) of the Metrecom System was found to be 2.7 mm. Repeatability in terms of the stability of the Metrecom System as indicated by deviations along the X, Y, and Z axes was .22, .57, and .31 mm, respectively. The results involving the Metrecom Method showed that the intraexaminer and interexaminer differences were not statistically significant (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
997.
998.
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.相似文献
999.
目的 :建立测定更昔洛韦滴眼液含量的高效液相色谱法。方法 :以HypersilC18为色谱柱 ,甲醇 水 (10∶90 )为流动相 ,检测波长 2 5 2nm。结果 :更昔洛韦在 2 .5~ 4 0mg·L-1浓度范围内线性关系良好 (r =0 .9998) ,平均回收率为 10 0 .7% ,RSD为0 .33%。结论 :本方法简便、快速、灵敏 ,可作为该滴眼液的质量控制。 相似文献
1000.