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71.
本文用中草药红背丝绸醇提物、乙酸乙脂提取物和单体CA-1201 三种不同成分对ET-1 在动物整体及离体水平生物学效应的拮抗作用进行了研究。结果发现:这三种成分对ET-1 致小鼠进行死亡有保护作用,使得小鼠的死亡率及死亡数下降;并可拮抗ET-1 致胸主动脉的缩血管效应,醇提物和乙酸乙脂提取物(10- 7母液)拮抗ET 缩血管效应分别为57.27% 和58.61% ;CA-1201 10- 8和10- 9 M 亦能拮抗ET-1 的缩血管效应;醇提物和乙酸乙脂提取物口服及CA-1201 静脉注射后能拮抗ET-1 的升压作用,拮抗ET-1 作用均呈现明显的剂量依赖性。提示中草药红背丝绸不同成分可拮抗ET-1 的生物学效应。  相似文献   
72.
对16例垂体腺瘤采用单侧鼻前庭切口经蝶切除,效果满意,既可减少手术创伤,又缩短了手术距离,且避免了美容缺陷,是一种设计巧妙,较为实用的手术方法,尤其适用于生长激素腺瘤。  相似文献   
73.
The chick chorioallantoic membrane (CAM) model was used to study vascular effects of photodynamic therapy (PDT) and hyperthermia (HPT) and the synergism of these modalities. The CAM is a convenient medium for monitoring the modifications of the vasculature. It is possible to view the CAM and to examine structural changes of individual blood vessels in real time. Moreover, the CAM is a closed system which lends itself to mathematical modeling of the temporal and spatial temperature profile and in which HPT can be performed quantitatively and to a selected depth, using different lasers. A porphyrin-type photosensitizer solution was applied to areas of the CAM, defined by teflon O-rings placed on the surface. Uptake dynamics of the sensitizer into the CAM was determined by analyzing its fluorescence in vivo. The CAM area was irradiated with a dual-wavelength laser system composed of a dye laser at 644 nm (to induce PDT) and a CO2 laser at 10.6 microns (to bring about HPT). Damage to the CAM vasculature, due to combined PDT+HPT, was compared to the outcome of the separate modalities, and a synergistic effect of about 40% was observed.  相似文献   
74.
以辣根过氧化物酶(PO)和抗-PO作为免疫沉淀中的抗原和抗体,用光电比色法,对78例小儿肾脏疾病血清补体对免疫沉淀的抑制作用(IIPC)进行了研究,并同时检测补体成分C3、C4。结果,正常对照IIPCOD值为0.505±0.085,急性肾小球肾炎(0.137±0.108)显著降低(P<0.001);慢性肾小球肾炎(0.470±0.053)改变不明显(P>0.05);肾病综合征(0.401±0.038)明显低下(P<0.05)。IIPC低下的发生率依次为急性肾小球肾炎(83%)、肾病综合征(43%)、慢性肾小球肾炎(32%)。表明小儿肾小球疾病时IIPC大多降低并与疾病的活动性有关。因此认为IIPC低下在肾脏病的发生和发展中起一定作用。  相似文献   
75.
76.
Laparoscopic nephrectomy was performed in 15 male pigs, the procedure was successful in 14. Extraction of the intact kidney through a 5-cm lower abdomen incision was done in 7 animals; complete destruction and evacuation of the kidney was accomplished by a round-knife suction device through a 1-cm port in another 7 pigs. Grossly, the specimen consisted of sausage-like tubular renal tissue and a small amount of tissue debris. Pathology revealed that the glomerular and tubular structures were well preserved, no interstitial hematoma could be found. Four ports were usually used, one 1-cm umbilical camera port, one 0.5-cm port for ureter traction, and two 1-cm working ports along the midclavicular line. All the pigs recovered uneventfully. The average operation time was 3 h 20 min. The application of endo-GIA (United States Surgical Corporation) for renal hilum reduced the operative time to 2 h 20 min. Complications included renal vein tear during endoclip application and cutting in the first case, mild subcutaneous emphysema in 2 cases. This first pig received exploratory laparotomy for the repair and ligation of the renal vein. No more major complications occurred with increasing experience. From this porcine experiment, we conclude that the combination of laparoscopy, a tissue destroyer and an endobag for the entrapment of kidney seem to be a promising technique for clinical nephrectomy.  相似文献   
77.
目的研究杜氏/贝氏进行性肌营养不良(DMD/BMD)携带者视网膜眼电图(ERG)的改变,探讨ERG对DMD/BMD携带者的诊断意义。方法对22个基因突变类型明确的DMD/BMD家系.用定量PCR法结合系谱分析将家系中女性成员分成肯定携带者和非携带者,对患者和家系女性成员进行详细的眼科检查和ERG检测,并用ERG国际测量标准记录结果。结果22名患者中17名出现异常ERG改变;11名肯定携带者中5名出现ERG异常,14名非携带者无ERG改变,两组无重叠。结论ERG是一项对DMD/BMD诊断非常敏感和特异的检查,而ERG对携带者的诊断也具有一定的临床意义。  相似文献   
78.
SARS家庭聚集型病例8例报告分析   总被引:1,自引:0,他引:1  
SARS是由变异冠状病毒引起的新型烈性传染病,具有在家庭和医院内聚集发病的特点。其影像学表现对于临床诊断和随诊观察具有重要价值。本文报告了分属3个家庭的8个病例发病早期(1周)影像学表现(包括胸部平片和CT)和部分临床表现资料,讨论并分析SARS早期影像学表现的若干特点及与临床表现之间的关系。  相似文献   
79.
Nuclear factor-kappaB (NF-kappaB) plays a key role in inflammation, which is involved in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). In the present study, we assessed the potential role of NF-kappaB in regulation of cerebral vasospasm. Nuclear factor-kappaB DNA-binding activity was measured in cultured vascular smooth muscle cells (VSMCs) treated with hemolysate and pyrrolidine dithiocarbamate (PDTC, 80 micromol/L), an inhibitor of NF-kappaB. Forty-two rabbits were divided into three groups: control, SAH, and PDTC groups (n=14 for each group). The caliber of the basilar artery was evaluated. Nuclear factor-kappaB DNA-binding activity and the gene expression levels of cytokines and adhesion molecules in the basilar artery were measured. Immunohistochemical study was performed to assess the expression and localization of tumor necrosis factor (TNF)-alpha, intercellular adhesion molecule (ICAM)-1, and myeloperoxidase (MPO). It was observed that NF-kappaB DNA-binding activity was significantly increased by treatment with hemolysate in cultured VSCMs, but this increase was suppressed by pretreatment with PDTC. Severe vasospasm was observed in the SAH group, which was attenuated in the PDTC group. Subarachnoid hemorrhage could induce increases of NF-kappaB DNA-binding activity and the gene expression levels of TNF-alpha, interleukin (IL)-1 beta, ICAM-1, and vascular cell adhesion molecule (VCAM)-1, which were reduced in the PDTC group. Immunohistochemical study demonstrated that the expression levels of TNF-alpha, ICAM-1, and MPO were all increased in the SAH group, but these increases were attenuated in the PDTC group. Our results suggest that NF-kappaB is activated in the arterial wall after SAH, which potentially leads to vasospasm development through induction of inflammatory response.  相似文献   
80.
Parkinson's disease (PD) is a major cause of disability. To date, there have been no large-scale efforts to measure the quality of PD care because of a lack of quality indicators for conducting an explicit review of PD care processes. We present a set of quality indicators for PD care. Based on a structured review of the medical literature, 79 potential indicators were drafted. Through a two-round modified Delphi process, an expert panel of seven movement disorders specialists rated each indicator on criteria of validity, feasibility, impact on outcomes, room for improvement, and overall utility. Seventy-one quality indicators met validity and feasibility thresholds. Applying thresholds for impact on outcomes, room for improvement, and overall utility, a subset of 29 indicators was identified, spanning dopaminergic therapy, assessment of functional status, assessment and treatment of depression, coordination of care, and medication use. Multivariable analysis showed that overall utility ratings were driven by validity and impact on outcomes (P < 0.01). An expert panel can reach consensus on a set of highly rated quality indicators for PD care, which can be used to assess quality of PD care and guide the design of quality improvement projects.  相似文献   
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