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101.
本文对近 10年收治 77例急性中毒的患儿进行了回顾性分析。观察到 :年幼小儿、农村小儿发病率较高 ,因误服药物、鼠药的食物致急性中毒的患儿较多 ,死亡病例均因就诊太晚。提示 :对急性中毒必须早诊断、早治疗。并提出减少小儿意外中毒的关键应从预防着手 相似文献
102.
Plate fixation of fresh displaced midshaft clavicle fractures 总被引:2,自引:0,他引:2
From 1992-1994, we operated on 251 fresh completely displaced mid-third clavicle fractures in adults; 232 were followed up. The fractures were plated with a Mizuho C-type plate or an AO/ASIF 3.5 mm reconstruction plate. Comminuted fragments were reduced and wired (133 cases). There were 150 men and 82 women; the median age was 37.3 years (range 18-79). The mean follow-up was 4.4 years (range 3.0-5.9). The mean time to radiographic union was 10 weeks. Seven patients (3%) developed nonunion. Healing with angulation occurred in 14 patients. Deep infection developed in one patient, and superficial infection in four cases; 21 patients reported soreness with changes in the weather and activity; 28 patients had residual skin numbness caudal to the incision. No patient had shoulder droop, and none had impairment of range of motion or shoulder strength. None developed new or late neurovascular impairment; 171 patients eventually had the hardware removed at an average 401 days post operatively. Overall, 94% were satisfied with the procedure. For completely displaced clavicle fractures in adults, plating is a reliable procedure. 相似文献
103.
The biosynthesis and secretion of pro-opiomelanocortin (POMC) was examined in the pituitary of Cpe(fat)/ Cpe(fat)mice, which are deficient in carboxypeptidase E, a sorting receptor for the regulated secretory pathway (Cool D R, Normant E, Shen F S, et al. Cell 1997; 83: 73-83). Dopamine inhibited forskolin-stimulated accumulation of cAMP in the intermediate lobe of Cpe(fat)/ Cpe(fat)mice, showing that their dopamine receptors were fully functional. This result indicates that the elevated, dopamine-insensitive POMC secretion previously observed in the intermediate pituitary of Cpe(fat)/ Cpe(fat)mice was constitutive, rather than due to defective dopamine receptors. Concomitant with the increase in POMC secretion was a twofold increase in POMC mRNA levels and [(35)S]-methionine incorporation into POMC. In the anterior pituitary of Cpe(fat)/ Cpe(fat)mice, a 1.6-fold increase in basal release of POMC was accompanied by a similar increase in [(35)S]-methionine incorporation into POMC, although POMC mRNA levels were unchanged. Thus, the intermediate and anterior pituitary of Cpe(fat)/ Cpe(fat)mice compensate for the constitutive secretion of POMC by upregulating biosynthesis. 相似文献
104.
正常眼共焦扫描激光多普勒视网膜血流图 总被引:7,自引:0,他引:7
目的 探讨共焦扫描激光多普勒视网膜血流图的临床应用价值。方法 应用Heidelberg共焦扫描激光多普勒视网膜血流图仪对48 例(82 只正常眼)视乳头及视网膜血流灌注进行检测。结果 视乳头大血管血流量为20314 ±7477,血流速为6 27243 ±2 26007 ,红细胞移动速率为1314 ±258 ;视乳头筛板处的血流量为2636 ±1474 ,血流速为46799 ±27015 ,红细胞移动速率为193 ±107 。颞侧视乳头盘沿的血流量为2290 ±1132,血流速为51453 ±37021,红细胞移动速率为169±112 ;鼻侧视乳头盘沿的血流量为2177 ±983,血流速为49321 ±29029,红细胞移动速率为165±090;颞侧与鼻侧比较差异无显著性(t 值分别为0682 5 ,0410 4,0250 1,P> 005) 。颞侧视乳头旁视网膜的血流量为3255 ±1300,血流速为55863 ±29345 ,红细胞移动速率为178 ±083;鼻侧视乳头旁视网膜的血流量为2061 ±892 ,血流速为35864 ±21266 ,红细胞移动速率为12 相似文献
105.
A spot weld & heating treatment tri-uses device based on modern mechanical-electric technique, was developed for dental spot weld, stainless steel orthodontic wire heating-reversion and Ni-Ti orthodontic wire heating-overload metamorphism. The device will be very helpful instrument in orthodontic clinic. The paper not only described the operating methods of the device, but also discussed the Performance-improved principles of stainless steel orthodontic wire and the principles of heating overload metamorphism of Ni-Ti orthodontic wire. 相似文献
106.
分离性垂直偏斜(简称DVD)亦称上隐斜。该病病因不清,治疗方法亦各不相同,临床较多采用上直肌减弱术。下斜肌止端转位术是KratZ1989年报道的一种新的DVD矫正术。近三年我们采用上直肌后徙术及下斜肌止端转位术治疗DVD,取得较好疗效。现报告如下,l临床资料11对象本组16例,年龄7一月岁,男6例,女10例,合并内斜9例,合并外斜5例,Helveston综合征2例。患者术前均行视力、屈光状态、眼位、注视性质、眼底、三棱镜及同视机检查。1.2手术设计及效果DVD手术定量主要根据第一眼位用交替遮盖试验测量最大斜视程度来决定,一般在Drp影… 相似文献
107.
Chorvat RJ Bakthavatchalam R Beck JP Gilligan PJ Wilde RG Cocuzza AJ Hobbs FW Cheeseman RS Curry M Rescinito JP Krenitsky P Chidester D Yarem JA Klaczkiewicz JD Hodge CN Aldrich PE Wasserman ZR Fernandez CH Zaczek R Fitzgerald LW Huang SM Shen HL Wong YN Chien BM Arvanitis A 《Journal of medicinal chemistry》1999,42(5):833-848
The synthesis and CRF receptor binding affinities of several new series of N-aryltriazolo- and -imidazopyrimidines and -pyridines are described. These cyclized systems were prepared from appropriately substituted diaminopyrimidines or -pyridines by nitrous acid, orthoester, or acyl halide treatment. Variations of amino (ether) pendants and aromatic substituents have defined the structure-activity relationships of these series and resulted in the identification of a variety of high-affinity agents (Ki's < 10 nM). On the basis of this property and lipophilicity differences, six of these compounds (4d,i,n,x, 8k, 9a) were initially chosen for rat pharmacokinetic (PK) studies. Good oral bioavailability, high plasma levels, and duration of four of these compounds (4d,i,n,x) prompted further PK studies in the dog following both iv and oral routes of administration. Results from this work indicated 4i,x had properties we believe necessary for a potential therapeutic agent, and 4i1 has been selected for further pharmacological studies that will be reported in due course. 相似文献
108.
Hepatotoxic alkylation of mouse liver cells by acetaminophen is characterized by an early loss of ion regulation, accumulation of Ca2+ in the nucleus, and fragmentation of DNA in vitro and in vivo. Acetaminophen-induced DNA cleavage is accompanied by the formation of a "ladder" of DNA fragments characteristic of Ca(2+)-mediated endonuclease activation. These events unfold well in advance of cytotoxicity and the development of necrosis. The present study utilized cultured mouse hepatocytes and mechanistic probes to test whether DNA fragmentation and cell death might be related in a "cause-and-effect" manner. Cells were isolated by collagenase perfusion, cultured in Williams' E medium for 22-26 hr, and exposed to acetaminophen. Aurintricarboxylic acid, a general Ca(2+)-endonuclease inhibitor, and EGTA, a chelator of Ca2+ required for endonuclease activation, significantly decreased DNA fragmentation at 6 and 12 hr and virtually abolished cytotoxicity. N-Acetylcysteine also eliminated DNA fragmentation and cytotoxicity. 3-Aminobenzamide, an inhibitor of poly(ADP-ribose) polymerase-stimulated DNA repair, failed to alter the amount of DNA fragmentation at 6 hr but substantially increased acetaminophen cytotoxicity in hepatocytes at 12 hr. With the exception of when DNA repair was inhibited by 3-aminobenzamide, Ca2+ accumulation in the nucleus, DNA fragmentation, and hepatocyte death varied consistently and predictably with one another. Collectively, these findings suggest that unrepaired damage to DNA contributes to acetaminophen-induced cell death in vivo and may play a role in necrosis in vivo. 相似文献
109.
Y H Shen 《中国中西医结合杂志》1992,12(11):677-9, 646
In order to observe the influence of modified Yu Ping Feng San (MYPFS) on bacterial adhesion of tracheal mucosa, four experiments of bacterial adhesion in pneumatic tract were conducted, in which mice of chronic bronchitis model (CBM) induced by SO2 stimulation and another health control group breathed in aerosol contained Pseudomonas aeruginosa under the same condition were observed. The results showed that, with scanning electron microscopy, ultrastructural lesions on tracheal mucosa surface and adhesive bacterial number in CBM administrated MYPFS were far less than that in CBM without MYPFS (P < 0.001), and quantitative culture of Pseudomonas aeruginosa with tracheal tissue homogenate was also markedly reduced. However, the tracheal mucosa of healthy control animals were intact, the adhesive bacteria were not found. It is suggested that bacterial adhesion was closely related to the injury of tracheal-mucosa, and MYPFS could play a role of anti-bacterial adhesion through the protection of tracheal mucosa epithelium or reduction of pneumatic tract injury. These were quite in accordance with the theories of traditional Chinese medicine in "strengthening body resistance to eliminate the pathogenic factor", so that they provided experimental evidence for TCM tonics to prevent and treat infection of respiratory tract. 相似文献
110.
Wisloclki Peter G.; Juliana M. Margaret; MacDonald James S.; Chou Ming W.; Yang Shen K.; Lu Anthony Y. H. 《Carcinogenesis》1981,2(6):511-514
The newborn mouse lung adenoma model has been shown to be asensitive test for studying the tumor-igenicity of bay regiondiol epoxides and their precursor dihydrodiols. When a totaldose of 28 nmol of 7, 12-dimethylbenz[a]anthracene (DMBA) orits derivatives was injected i.p. into the preweaning mice,it was found that the 3, 4-dihydrodiols of both DMBA and 7-hy-droxymethyl-12-methylbenz[a]anthracenecaused 13.3 and 4.1 times more lung adenomas than DMBA, respectively.The mice treated with the 5, 6- and 8, 9-dihydro-diols of DMBA,7-hydroxymethyl-12-methylbenz[a]-anthracene and its 5, 6- 8,9-and 10,11-dihydrodiols, 7-methyl-12-hydroxymethylbenz[a]an-thraceneand 7,12-dihydroxymethylbenz[a]anthracene developed a levelof lung adenomas/mouse less than Mold higher than that foundin the DMSO-treated control group. Liver tumors also developedin some of the mice. The percentage of mice with liver tumorsalso indicated that the 3, 4-dihydrodiols of both DMBA and 7-hydroxymethyl-12-methylbenz[a]anthracenewere more tumorigenic than DMBA itself. These data indicatethat the 3, 4-dihydrodiols of both DMBA and its 7-hydroxymethylderivative may be proximate carcinogenic metabolites of DMBAin the newborn mouse. 相似文献