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81.
Antegrade locked nailing for humeral shaft fractures 总被引:19,自引:0,他引:19
Treatment results of antegrade locked nailing of acute humeral shaft fractures, including union rate and recovery of shoulder function, have been inconsistent. This led the current authors to hypothesize that implant design and surgical techniques might account for this inconsistency. In the current study, 47 fractures (38 acute; nine pathologic) in 47 patients achieved union with the techniques of closed nailing, short to long segment nailing, and fracture compression. Satisfactory recovery of shoulder function occurred because of minimal surgical trauma, prevention of impingement by the nail or locking screws, and prevention of axillary nerve injury or comminution of the humeral head. Forty-seven patients with 38 acute fractures and nine pathologic fractures were treated with humeral locked nails. Mean followup time was 21.4 months. With a single operation, all 38 acute fractures proceeded to eventual union; the average time to union was 7.8 weeks. Thirty-five patients had excellent or satisfactory recovery of shoulder function. Complications included slipout of the proximal screw, nail breakage, fragment displacement, and transient postoperative radial nerve palsy. All nine patients with pathologic fractures had substantial pain relief and increased arm function after surgery. The current study shows the reliability of antegrade locked nailing for proximal and middle third fractures of the humeral shaft. 相似文献
82.
Optimization of fast acquisition methods for whole-brain relative cerebral blood volume (rCBV) mapping with susceptibility contrast agents 总被引:1,自引:0,他引:1
Hou L Yang Y Mattay VS Frank JA Duyn JH 《Journal of magnetic resonance imaging : JMRI》1999,9(2):233-239
Fast gradient-echo magnetic resonance scan techniques with spiral and rectilinear (echoplanar) k-space trajectories were optimized to perform bolus-tracking studies of human brain. Cerebral hemodynamics were studied with full brain coverage, a spatial resolution of 4 mm, and a temporal resolution of 2 seconds. The sensitivity of the techniques to detect image signal-intensity changes during the first pass of the contrast agent was studied at a range of TEs using dedicated experiments. For single-shot versions of spiral scanning and echoplanar imaging techniques with a 0.1-mmol/kg injection of gadolinium diethylenetriamine pentaacetic acid using a mechanical injector at 10 mL/sec under 1.5 T, the maximum sensitivity was obtained at TEs between 35 and 45 msec. At TEs less than 35 msec, signal-intensity artifacts were observed in the images. Analysis of the point-spread function revealed that susceptibility changes induced by the contrast agent can result in signal shifts to neighboring voxels. These artifacts are attributed to susceptibility-related signal changes during the acquisition window. 相似文献
83.
Studies on plasma endothelin changes in varicocele patients 总被引:1,自引:0,他引:1
Aim: To investigate the possible role endothelin may play in the pathogenesis of varicocele and varicocele-induced infer-tility. Methods: In varicocele patients, radioimmunoassay is used to determine the blood endothelin concentration inthe spermatic vein and the antecubital vein separately. Results: The blood endothelin concentration of the spermaticvein (66.8±23.5 pg/mL) was significantly higher (P <0.05) than that of the antecubital vein (55.3±25.3 pg/mL).The endothelin concentration in the spermatic vein in Grade Ⅱ varicocele patients was not significantly different from thatin Grade Ⅲ patients ( P = 0.87). Conclusion: The higher blood endothelin level in the spermatic vein may indicate theinvolvement of endothelin in the pathophysiology of varicocele and varicocele-induced infertility. (Asian J Androl 1999Sep ; 1: 159 - 160) 相似文献
84.
Transforming Growth Factor-β2 mRNA Level in Unloaded Bone Analyzed by Quantitative In Situ Hybridization 总被引:2,自引:0,他引:2
The effects of tail suspension hypokinesia on the gene expression for TGF-β2 at different sites within bone were evaluated. TGF-β2 mRNA signal levels were determined quantitatively by an image analysis system. The osteopenia induced by tail suspension
was verified by histomorphometry. In the periosteum of nonsuspended control rats, TGF-β2 mRNA was highly expressed in the preosteoblasts and osteoblast-rich cambial layers; very little signal was present within
the middle and outer fibroblastic layers. Gene expression was significantly reduced in suspended rats, and this was evident
both in terms of the number of silver grains in unit area or length of tissue and in each osteoblast and preosteoblast. Hypokinesia
also reduced the expression of TGF-β2 mRNA level in cortical and trabecular bone osteocytes, but did not adversely affect the mRNA level in chondrocytes in growth
plate. The results affirm the site-specific response of TGF-β2 gene expression in rats, and suggest that the cortical and trabecular bone osteopenia associated with hypokinesia in rats
may be associated with a deficit in osteoblastic and osteocytic TGF-β2 level.
Received: 6 February 1998 / Accepted: 10 November 1998 相似文献
85.
胃肠道癌手术与门静脉单细胞转移的相关性研究 总被引:10,自引:1,他引:9
目的 进一步了解在胃癌、大肠癌的根治过程中,手术对单细胞转移的影响。方法 172例2分2组,阳性受检组111例,先结扎肿瘤区引渡以血和的阴性对照组61例。开腹探后将导管置入门静脉抽取血标本,抗上皮细胞膜克隆抗体为探针,ABC免疫组化法检测门静脉癌细胞。结果 阳性受检组111例患者中有72例发现肿瘤细胞、阳性率为64.9%,有性对照组的61例仅发现13例,阳性率为21.3%,两组且间差异有显著性, 相似文献
86.
窥镜下激光治疗前列腺增生症 总被引:2,自引:0,他引:2
目的 评价经尿道激光前列腺切除术(TULP)的疗效及其与前列腺大小的关系。方法 回顾分析了1988年至1998年10年,采用TULP治疗的469例前列腺增生症患者对手术技术、手术前后的症关改善情况进行比较,并对233例符合条件的患者TULP手术效果与前列腺大小的相关性进行了研究。结果 469例患者前列腺症状评分(IPSS)平均值由术前的26.7降到术后的14.2;最大尿流率平均值由6.2ml/s上 相似文献
87.
U Carstensen S M Hou A K Alexandrie B H?gstedt C Tagesson M Warholm A Rannug B Lambert A Axmon L Hagmar 《Scandinavian journal of work, environment & health》1999,25(4):351-360
OBJECTIVES: Airborne exposure to polycyclic aromatic hydrocarbons (PAH) in the potroom of an aluminum reduction plant was studied in relation to genotoxic or mutagenic effects, and the possibility of host genotypes of different metabolizing enzymes modifying associations between PAH exposure and genotoxic or mutagenic response was assessed. SUBJECTS AND METHODS: Ninety-eight male potroom workers and 55 male unexposed blue-collar workers constituted the study population. Micronuclei in CD4+ and CD8+ lymphocytes, DNA (deoxyribonucleic acid) single-strand breaks, hypoxanthine guanine phosphoribosyl transferase (HPRT) mutation frequency, and genotype for cytochrome P-4501A1, glutathione transferases M1, T1 and P1, and microsomal epoxide hydrolase were analyzed using peripheral mononuclear cells. Urine samples were collected for the analysis of 8-hydroxydeoxyguanosine. RESULTS: Micronuclei in peripheral CD4+ and CD8+ lymphocytes, DNA single-strand breaks, HPRT mutation frequency, and 8-hydroxydeoxyguanosine in urine did not differ between the potroom workers and the unexposed referents. With the exception of an observed exposure-response relationship for potroom workers with Tyr/Tyr genotype for microsomal epoxide hydrolase, between airborne PAH and CD8+ micronuclei, no correlations were found between any of the genotoxicity biomarkers and any of the exposure measures (airborne particulate PAH, airborne gas phase PAH, length of employment in the potroom, 1-hydroxypyrene in urine, or PAH-DNA adducts in peripheral lymphocytes), also when genotypes for biotransforamtion enzymes were considered. CONCLUSIONS: The results indicate that the employed biomarkers of mutagenic or genotoxic effects are not appropriate for surveillance studies of potroom workers exposed to current airborne levels of PAH. The significance of the correlation between airborne PAH and CD8+ micronuclei in Tyr/Tyr genotype subjects should be evaluated. 相似文献
88.
目的探讨治疗臁疮的有效方药;方法应用白行研制的愈溃膏,采用外敷的方法,治疗臁疮80例,同期常规治疗45例作为对照;结果应用愈溃膏治疗80例患均取得较好效果,明显优于对照组;结论愈溃膏对于臁疮有较好疗效。 相似文献
89.
Y Nakai W L Dean Y Hou N A Delamere 《Investigative ophthalmology & visual science》1999,40(7):1460-1466
PURPOSE: To determine whether dopamine receptor stimulation regulates Na,K-ATPase-mediated ion transport in cultured nonpigmented ciliary epithelium (NPE). METHODS: Using a rabbit NPE cell line, active Na-K transport activity was determined by measuring ouabain-sensitive potassium (86Rb) uptake in cell monolayers. Western blot analysis of membrane material obtained from cell homogenates was conducted to examine tyrosine phosphorylation of membrane proteins. RESULTS: Ouabain-sensitive potassium (86Rb) uptake was inhibited in the presence of either dopamine or the D1-selective agonist SKF82958. The response was suppressed by SCH23390, a D1 antagonist, but not by sulpiride, a D2-selective antagonist. Quinpirole, a D2-selective agonist, did not cause inhibition of ouabain-sensitive potassium (86Rb) uptake. Cyclic adenosine monophosphate (cAMP) was detectably increased in SKF82958-treated cells, although the concentration of SKF required to elevate cell cAMP was higher than the concentration needed to inhibit ouabain-sensitive potassium (86Rb) uptake. The protein kinase A inhibitor H89 prevented the 86Rb uptake response to SKF82958. Genistein, an inhibitor of tyrosine kinases, also prevented the 86Rb uptake response to SKF82958. Membrane material isolated from cells exposed to SKF82958 showed an increase in the density of several phosphotyrosine bands. These changes in phosphotyrosine immunoblot density were not observed in material isolated from cells that received either genistein or SCH23390 before SKF82958 treatment. CONCLUSIONS: The results of this study suggest D1 agonists cause a reduction of Na,K-ATPase-mediated ion transport by a mechanism that could involve a tyrosine kinase step. 相似文献
90.
本文调查分析1所大型综合性医院1989-1994年麻醉性镇痛药使用情况,平均年消耗量为29645±s5591DDDs。年开支金额逐年增加,1994年为1990年的440%。内科用量占全院的55.3%,二氢埃托啡片1991年猛增至10万片以上,卫生部下达文件后下降。门诊麻醉镇痛药用量占4.9%,其处方量占总处方量的0.35%。主要使用单位是急诊科,占70.2%。男女患者比为2.4:1;26-45aa组占45.6%。药物利用指数0.29-0.70,使用不当者主要是二氢埃托啡,发现2人发生依赖性。43名癌痛患者很少按“三阶梯止痛疗法”给药。根据存在的问题,本文提出相应的建议。 相似文献