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991.
脊髓损伤后并发肺损伤的实验研究   总被引:2,自引:0,他引:2  
目的探讨脊髓损伤后并发肺损伤的机理、病理及治疗方法。方法家兔40只,通过改良Allen法制成脊髓损伤模型,截瘫按Talove分级为1~2级,分为治疗组(B)和对照组(A),治疗组于伤后3h开始自静脉给予常规剂量(0.35mg/kg)的地塞米松治疗,分别于不同的时相点处死家兔,观察动物肺脏的病理改变。结果家兔脊髓损伤后均发生了不同程度的肺脏损伤,肺出血(100%)。脊髓损伤所致的肺出血,治疗组明显轻于对照组(P<0.01)。结论脊髓损伤均并发不同程度的肺损伤。肺损伤的发生机理主要是神经-体液应急反应。应用常规剂量的地塞米松即可以有效地预防和治疗脊髓损伤并发的肺损伤。  相似文献   
992.
目的 探讨单开门棘突重建颈椎管扩大成形术治疗无骨折脱位型颈脊髓损伤的疗效。方法 无骨折脱位型颈脊髓损伤15例,均行单开门棘突重建颈椎管扩大成形术。采用JOA、Frankel分级及影像学进行疗效评价。结果 平均随访2年5个月,JOA评分术后改善率为35.83%,Frankel分级B→C1例,C→C2例,C→D7例,D→D2例,D→E3例。影像学检查示15例颈椎生理屈度正常,未发现有再“关门”及不稳定现象。结论 单开门棘突重建颈椎管扩大成形术由于重建了颈后方韧带复合体,对于改善和维持颈椎的生理曲度、稳定性方面具有重要的临床意义。  相似文献   
993.
超声引导经皮射频治疗肝脏良恶性肿瘤   总被引:18,自引:1,他引:18  
目的 评价经皮射频(PRFA)治疗肝脏良恶性肿瘤的效果、安全性及实用性。方法 应用RF-2000射频仪和10电极LeVeen射频针经皮穿刺治疗肝脏恶性肿瘤114例153个病灶和良性肿瘤13例16个病灶,共计127例169个病灶。B超引导监测,局麻配合全身镇痛处理,对于肿瘤病灶大于2.5cm者进行分层多点叠合毁损,大于5.0cm或多发的恶性肿瘤配合肝动脉导管化疗栓塞术,随访观察治疗效果、并发症和生存情况。结果 实施成功率100%,PRFA治疗肝脏恶性肿瘤并发症发生率6.14%(7/114),均保守治愈,无相关死亡。PRFA治疗肝脏良性肿瘤未遇并发症,病人均健在。114例肝脏恶性肿瘤病人的3个月、6个月、1年、2年、3年生存率分别为100%(114/114)、97.4%(111/114)、74.6%(85/114)、59.4%(41/69)和36.8%(7/19)。结论 PRFA微创、有效、简捷、实用、可重复、相对安全,在肝脏恶性肿瘤的综合治疗中有重要价值,亦可作为肝脏良性肿瘤的一种选择疗法。  相似文献   
994.
多次胆道术后老年重症胆管炎的手术时机与方法   总被引:1,自引:0,他引:1  
目的 探讨多次胆道术后老年重症胆管为患者手术时机和方法。方法 回顾性分析46例60 y以上多次胆道术后老年重症胆管炎患者临床资料。结果 46例全部行手术治疗,择期手术44例(95.65%),急诊手术2例(4.35%),术前伴随一种并存病93.47%(三种以上并存病19.56%);术后并发症39.02%,死亡率6.81%,2例ACST术前死于中毒性休克及MODF。术后死亡3例,2例死于MODF,1例死于心肺骤停。结论 掌握手术时机和方法,不前行PTCD或EBEBND,处理并存病,争取择期手术,避免急诊手术盲目性是外科治疗多次胆道术后老年重症胆管炎,减少并发症。降低死亡率的关键。  相似文献   
995.
Yan L  Crabtree NJ  Reeve J  Zhou B  Dequeker J  Nijs J  Falch JA  Prentice A 《BONE》2004,34(3):584-588
To explore whether there are ethnic differences in calculated hip strength that might explain the low incidence of hip fracture in China, we used Lunar DPX 'beta' version of hip strength analysis (HAS) and hip axis length (HAL) programs to compare hip geometry, calculated strength and densitometric values from Chinese subjects in Shenyang to those of Caucasian subjects in Oslo and Leuven participating in the European Prospective Osteoporosis Study (EPOS). Subjects were 210 Chinese and 403 Caucasian men and women aged 53-77 years. Parameters investigated included bone mineral density (BMD), bone mineral content (BMC), bone area (BA), cross-sectional moment of inertia (CSMI) and section modulus (both indicating strength and rigidity of the femoral neck), HAL, neck length (NL), neck diameter, tensile stress (Tstress) and compressive stress (Cstress) (indicating the stress in the femoral neck at its weakest cross section arising from walking or a standard fall, respectively), safety factor (SF, indicating the resistance to fracture for forces generated during walking) and fall index (FI, indicating the resistance to fracture from force generated during a fall in the greater trochanter). The Chinese men and women were significantly shorter and lighter than their Caucasian counterparts (P<0.01) and had significantly lower BMD, BMC and BA of the femoral neck (P<0.01). After adjusting for BA, weight and height, there was no significant ethnic difference in either gender in BMC. CSMI and section modulus were significantly lower, and HAL, NL and neck diameter were significantly shorter in the Chinese men and women (P<0.01). These differences all remained after adjusting for weight and height. There were no significant differences in Tstress, Cstress, SF and FI between ethnic groups in either gender. Most of the parameters of calculated hip strength in the Chinese subjects were similar to or poorer than those in the Caucasian subjects. There was no evidence to indicate that Shenyang Chinese have superior BMD or BMC or better calculated hip strength. The short HAL and NL of the population, however, could be an independent factor contributing to the low incidence of hip fracture.  相似文献   
996.
The use of immunosuppressive drugs in models of chronic rejection may limit their usefulness for mechanistic studies. We have developed a new minor histocompatibility-mismatched rat kidney transplant model without the need for immunosuppression. Kidneys from LEW (RT1(l)) donors were transplanted to congenic WF.1L (RT1(l)) recipients and compared with the reversed strain combination and isogenic controls. Urinary protein excretion was measured serially in all recipients; kidneys were harvested 90, 120, and 180 d after transplantation for morphologic analysis and cytokine gene expression. In vitro lymphocytic reactivity and cytokine analysis of mixed lymphocyte reaction (MLR) culture supernatants by ELISA was also carried out. LEW into WF.1L kidney grafts developed proteinuria starting 120 d after transplantation and were associated with morphologic changes of focal segmental glomerulosclerosis together with interstitial cell infiltrates, upregulated gene expression of IL-1beta, IL-2, and TNF-alpha/-beta, as well as IL-2, IFN-gamma, and TNF-alpha production by lymphocytes in MLR culture supernatants. WF.1L kidneys transplanted into LEW recipients did not develop chronic rejection and had upregulation of Th2 cytokines, both within the allograft and in MLR supernatant of recipient lymphocytes cultured with WF.1L cells. Furthermore, these lymphocytes produced both Th1 and Th2 cytokines when cultured with WF cells, unlike lymphocytes from the LEW isografts, which produced Th1 cytokines when challenged with WF cells. These studies show that indirect allorecognition can cause strain-dependent chronic rejection associated with Th1-like cytokine production, whereas production of Th2 cytokines is associated with protection from the development of chronic rejection.  相似文献   
997.
PURPOSE: We describe our pilot experience with percutaneous cryoablation of renal masses using real-time sonography. MATERIALS AND METHODS: Three patients presented with 4 renal masses in 4 kidneys, which enhanced with contrast administration by computerized tomography or magnetic resonance imaging criteria. Renal neoplasm cryoablation was performed using general anesthesia with 17 gauge cryoneedles percutaneously placed into the renal tumor under real-time sonographic guidance. Followup cross-sectional imaging was performed 6 to 7 weeks following cryoablation in all patients. RESULTS: No perioperative complications were noted. All patients were discharged home within 24 hours of the procedure and postoperative pain was controlled with oral nonnarcotic medications. Followup cross-sectional imaging indicated that the lesions shrank an average 63% +/- 15% from initial pretreatment volume. Importantly none of the lesions showed contrast enhancement by computerized tomography or magnetic resonance imaging criteria. CONCLUSIONS: Our initial experience shows that percutaneous, sonographically guided renal neoplasm cryoablation can be a safe method for treating renal masses.  相似文献   
998.
AIMS: Weakening of pelvic supportive tissues is thought to be a contributing etiology in female pelvic floor disorders such as stress urinary incontinence and/or pelvic organ prolapse (SUI/POP). Since elastin modulates the mechanical properties of supportive tissues, we examined elastase activity in vaginal tissue from women with pelvic floor dysfunction compared to asymptomatic controls, by comparing overall elastase activity, human neutrophil elastase, cathepsin K, and alpha-1 antitrypsin (a serine protease inhibitor) mRNA and protein levels. METHODS: Full-thickness peri-urethral vaginal wall tissues were collected from age and menstrual-phase matched SUI/POP and control women at the time of pelvic surgery. Elastolytic activity in the homogenized tissue was determined by the generation of amino groups from succinylated elastin. To quantify mRNA levels of each protein, quantitative competitive-PCR and confirmatory Western blot analyses were performed on the samples for human neutrophil elastase, cathepsin K, and alpha-1 antitrypsin. RESULTS: The mean elastolytic activity in vaginal tissues from the SUI/POP group was similar to that in the control group. With respect to the proteolytic enzymes, neither human neutrophil elastase nor cathepsin K differed between the two groups. However, alpha-1 antitrypsin mRNA and protein levels were significantly decreased in tissues from affected women. CONCLUSIONS: A significant decrease in alpha-1 antitrypsin expression was seen in tissues from women with SUI/POP compared to controls. This data suggest that altered elastin metabolism may contribute to the connective tissue alterations observed in pelvic floor dysfunction. Future investigations are warranted to help define the role of elastin turnover in pelvic floor dysfunction.  相似文献   
999.
对假单胞菌Y8产壳聚糖酶培养条件进行研究,得到一个比较优化的培养条件为:pH值6.5,温度32℃,壳聚糖3g/L,酵母膏质量分数0.3%,培养时间3d.不同金属离子及不同诱导物对酶合成的影响表明:Fe2+激活作用显著,而Mg2+,Zn2+,Mn2+则具有一定的抑制作用,壳聚糖和氨基葡萄糖对壳聚糖酶的产生都有较好的诱导作用.  相似文献   
1000.
OBJECTIVES: Treatment of intra-abdominal infections remains a challenge because of their polymicrobial nature and associated mortality risk. Broad-spectrum empiric coverage is usually required. This randomized study compared the efficacy and safety of intravenous piperacillin/tazobactam with those of intravenous imipenem/cilastatin in the treatment of 293 hospitalized patients with intra-abdominal infection. METHODS: A total of 149 patients received piperacillin/tazobactam 4 g/500 mg every 8 hours, and 144 patients received imipenem/cilastatin 500 mg/500 mg every 6 hours. Efficacy was evaluated by clinical and bacteriological response. Safety was evaluated by analysis of adverse events and physical and laboratory examinations. RESULTS: Clinical and bacteriological responses in both evaluable treatment groups were equivalent. The clinical success was 97% (108/111) for piperacillin/tazobactam and 97% (100/103) for imipenem/cilastatin. Bacteriological success was 97% (67/69) for piperacillin/tazobactam and 95% (61/64) for imipenem/cilastatin. The most common pathogens were Escherichia coli, Klebsiella pneumoniae, Enterobacter species and Pseudomonas aeruginosa. The frequencies of treatment-related adverse events were similar (16 with piperacillin/tazobactam and 19 with imipenem/cilastatin). CONCLUSIONS: These results suggest that the safety and efficacy of piperacillin/tazobactam administered every 8 hours are equivalent to those of imipenem/cilastatin administered every 6 hours for the treatment of intra-abdominal infections.  相似文献   
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