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111.
目的 研究慢性"炎症性"肺动脉高压大鼠在肺动脉高压形成过程中肺动脉蛋白激酶C(PKC)亚型的表达.方法 建立野百合碱诱导的慢性"炎症性"肺动脉高压大鼠模型,应用Western blot技术检测肺动脉高压形成过程中大鼠肺动脉四种PKC亚型(PKCα、PKCβⅡ、PKCδ和PKCε)的表达变化.结果 PKCα、PKCβⅡ和PKCδ亚型在正常和肺动脉高压大鼠肺动脉中均有表达,而PKCε亚型未检测到.在肺动脉高压形成过程中,大鼠肺动脉胞浆和胞膜组分表达的PKCα均逐渐上升,到第14天达到高峰后略有下降,且胞膜表达量的升高远比胞浆明显.胞浆PKCβⅡ和PKCδ表达量均在第8天达最高,而胞膜中二者均表现出持续升高的趋势.结论 PKCα、PKCβⅡ和PKCδ亚型可能参与了慢性"炎症性"肺动脉高压的形成,其表达变化可能与其转位有关.  相似文献   
112.
Performance measurement of the microPET focus 120 scanner.   总被引:6,自引:0,他引:6  
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals.  相似文献   
113.
改良犬原位背驮式肝移植的解剖学观察   总被引:1,自引:0,他引:1  
目的观察犬肝脏解剖学特点,探索建立改良的犬同种异体原位背驮式肝移植模型。方法对15只杂交犬的肝脏进行活体和尸体标本的解剖观察。结果犬肝共分7叶,门静脉分左右支进入肝脏,门静脉左支供应约70%肝组织(Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ叶),门静脉右支供应约30%肝组织(Ⅵ、Ⅶ叶),分别阻断门静脉左、右支后5 min左右门静脉压力达到峰值,并迅速回复至门静脉正常压力值上限范围内;肝动脉和胆管与门静脉分支伴行进入各肝叶;左肝静脉粗大,可以作为肝静脉重建的流出道,其余3~6支肝静脉可以分别结扎,肝后下腔静脉易于与肝脏分离。结论犬肝的解剖学特点适宜于建立改良的原位背驮式肝移植模型。  相似文献   
114.
钬激光碎石术治疗复杂性输尿管结石(附87例报告)   总被引:1,自引:0,他引:1  
目的探讨复杂性输尿管结石经钬激光腔内治疗的有效性及安全性。方法回顾性分析2003年12月~2005年5月收治的经输尿管镜钬激光治疗复杂性输尿管结石87例的临床资料。87例均伴有患侧轻~中度肾盂积水,其中46例合并结石远端输尿管狭窄,69例合并有息肉或肉芽组织包裹,21例为ESWL治疗失败后。结果87例中83例单次手术碎石成功,单次手术结石粉碎率达95.4%(83/87),2例结石在钬激光碎石过程中移位于肾盏,术后再行ESWL治疗;1例进镜时输尿管穿孔,1例术中退镜时输尿管黏膜撕脱改为开放手术。结论输尿管镜下钬激光碎石术治疗复杂性输尿管结石安全、有效,尤其适用于体外冲击波碎石效果不佳的患者。  相似文献   
115.
OBJECTIVE: The recent development of fetal ultrasonography has allowed for an increasing number of prenatal diagnoses for congenital cystic adenomatoid malformation (CCAM). However, the appropriate surgical timing of these patients has not been studied as of yet. The aim of this study is to suggest a safe strategy for the treatment of CCAM by identifying the relationship between the timing of surgery and postoperative outcome. METHODS: Between 1987 and 2003, 40 patients (28 males, 12 females) underwent surgical resection for CCAM. The mean age was 38.6+/-9.1 (2 days-13 years) months. CCAM was diagnosed by prenatal ultrasonography in eight patients. Early operations were performed in four out of the eight. Operation was deferred until 2-12 months of age for the remaining four patients. RESULTS: Type I CCAM was found in 20 patients, type II in 20 and no patient exhibited type III. Five patients had associated pectus excavatum anomaly. There were no cases of operative mortality. Seventeen minor postoperative complications developed in 16 patients (40.0%): prolonged chest tube drain in 10, wound infection in 4, and 1 case of pneumonia, empyema and pleural space, respectively. The average hospital stay was 11.8 (6-29) days. During the mean follow-up period of 67.5 months, one patient died of accidental aspiration 7 months after operation during the postoperative recovery course of Ravich operation for pectus excavatum. The remaining patients reported doing well with normal physical activity. All five patients who underwent surgery at the age of under 1 month did not exhibit increased postoperative morbidity. CONCLUSIONS: We concluded that surgery for CCAM could be safely performed in all age groups with satisfactory long-term outcomes. It is suggested that early elective surgical correction can be recommended for a patient whose diagnosis was made in utero.  相似文献   
116.
Straight back syndrome (SBS) is a thoracic deformity with absence of upper thoracic spine kyphosis and heart compression. The anatomic abnormity of SBS may raise the difficulty of introcardial operation and increase the complicated risk of intervention performance. Here we report a case of SBS with complicated transseptal puncture during intervention catheter ablation of atrial fibrillation.  相似文献   
117.
目的观察过敏康Ⅱ号胶囊对AsAb阳性大鼠睾丸Bcl-2、Bax表达的影响。方法选取健康成年雄性SD大鼠60只,按体重随机分为正常组,模型组,对照组,高、中、低剂量组,每组10只。采用主动免疫法建立血清抗精子抗体(AsAb)阳性动物模型10只,灌胃给药,免疫组化方法观察药物对AsAb阳性大鼠睾丸Bcl-2、Bax表达的影响。结果过敏康Ⅱ号高剂量组睾丸生精细胞和精子Bcl-2表达的平均吸光值显著高于模型组(P〈0.01),而Bax表达的平均吸光值显著低于模型组(P〈0.01)。结论调节睾丸Bcl-2、Bax的表达是过敏康Ⅱ号清除或抑制AsAb起治疗作用的机制之一。  相似文献   
118.
目的:探讨胃癌肝细胞生长因子受体(c-Met)及肝细胞生长因子(HGF)表达与胃癌肝转移间的相关性。方法:晚期胃癌标本59例,其中11例同时有取自左肝外叶的肝转移标本,应用免疫组化方法对上述组织石蜡标本进行检测。结果:59例胃癌中,c-Met阳性率55.8%(33/59),HGF阳性率28.8%(17/59);在29例发生了同时或异时性肝转移的胃癌标本中,c-Met表达率为75.9%(22/29),HGF阳性率为37.9%(11/29),其中c-Met表达率在有和无肝转移组间有显著差异(P<0.05);在11例胃癌肝转移灶中,9例c-Met阳性表达率为81.8%,3例HGF阳性表达率为27.3%。结论:胃癌组织c-Met表达可能与胃癌肝转移行为相关。  相似文献   
119.
输尿管镜气压弹道碎石治疗输尿管结石110例   总被引:9,自引:2,他引:7  
目的总结输尿管镜气压弹道碎石治疗输尿管结石的临床效果。方法采用F8/9.8 Wolf硬性输尿管镜、JUN—AIR气压弹道碎石机治疗110例输尿管结石。结果输尿管镜直视下一次碎石成功105例,成功率95.5%(105/110),1~6周内结石全部排净。2例因置镜失败改开放手术,3例输尿管上段结石上移至肾脏行ESWL2例,口服排石药物治疗1例。术后泌尿系感染5例,轻度肉眼血尿1~3d。结论输尿管镜气压弹道碎石是治疗输尿管中、下段结石的有效方法之一,具有碎石率高、安全、并发症少、操作简单的优点。  相似文献   
120.
四氧化三铁微粒与碘化油混悬液栓塞兔肾动脉的实验研究   总被引:1,自引:0,他引:1  
目的 探讨四氧化三铁(Fe3O4)微粒与碘化油(Lp)混悬液(suspension from magnetic microspheres with lipi odol, S Fe3O4 Lp)对兔肾动脉的栓塞和导向作用机制。方法 测定工业工艺制备粒径为 50~250μm 5 种规格的 Fe3O4微粒在Lp中的沉降时间、速度;实验组用粒径250μm的S Fe3O4 Lp对右肾动脉栓塞,对照组用Lp栓塞。两组于术后不同时间比较栓塞效果、观察血生化和病理学改变。结果 五种粒度的Fe3O4 微粒能在一定时间范围内悬浮于Lp中;栓塞效果实验组优于对照组;实验组栓塞部位Fe3O4 微粒与Lp存留存在明显正相关关系(P<0.005,r=0.76)。结论 粒径为250μm的S Fe3O4 Lp对兔肾动脉栓塞效果好,无明显毒副反应;栓塞过程中Fe3O4 微粒与Lp具有同步、同向性,是S Fe3O4 Lp发挥导向性栓塞的基础。  相似文献   
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