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101.
CT增强扫描在评价NSCLC血管生成中的临床意义 总被引:3,自引:3,他引:0
目的 探讨非小细胞肺癌 (NSCLC)血管内皮生长因子 (VEGF)的表达水平与CT增强程度的关系 ,从影像学角度评价肿瘤血管生成在肺癌诊断、治疗及淋巴结转移中的临床价值。方法 对 30例NSCLC病人进行动态螺旋CT扫描 (SCT) ,测量病灶增强幅度 ,并利用免疫组化技术检测VEGF。对病灶增强值、VEGF阳性表达及淋巴结转移情况进行统计学分析。结果 30例肺癌病人CT增强值均数为 (36 .2 8± 6 .41 )HU ,VEGF阳性表达 2 1例 ,阴性表达 9例。VEGF在中晚期的阳性表达高于早期病人 (Ρ<0 .0 5) ,淋巴结转移组高于非淋巴结转移组 (Ρ <0 .0 5) ;癌灶增强值与VEGF阳性表达、肿瘤分期及淋巴结转移亦呈正相关。结论 NSCLC的CT增强程度能够反映肿瘤的血管生成 ,并与淋巴结转移密切相关 ,有助于肺癌的诊断、TNM分期 ,而且可以从肿瘤分子生物学行为方面补充目前肺癌分期方法的不足 相似文献
102.
103.
A method has been derived for calculating the mean absorption time of an oral drug and its interconversion metabolite which is generated from the drug systemically and presystemically. The method evolves from the convolution integral and requires plasma AUC and AUMC values after separate intravenous administration of the drug and its interconversion metabolite and oral administration of the drug. It can also be used to calculate the mean input time of a drug undergoing reversible metabolism and administered by any other extravascular route. Results of a simulation study using both errorless and errant data indicate that, when the absorption rate constant of a drug or its interconversion metabolite is not much larger than the apparent elimination rate constant, the proposed method performs satisfactorily. However, when the absorption rate constant of a drug or its interconversion metabolite is much larger than the apparent elimination rate constant, the proposed method appears to be inaccurate. 相似文献
104.
一种便携式野战多功能骨科手术器械。重量仅1.1kg,体积为215mm×105mm×15mm,如铅笔盒,而功能多达33种,具有结构紧凑、操作简便、一械多用、轻巧便携。价廉实用、效价比高的特点。是基层巡诊、抢险救灾救治中适用的骨科器械。 相似文献
105.
电针对沙鼠急性脑缺血再灌注后神经原损伤的保护作用 总被引:9,自引:0,他引:9
本实验利用沙鼠急性脑缺血再灌注模型,研究电针对脑缺血及再灌注各期脑电活动的影响及组织病理学的改变。结果表明:缺血10mln,脑电幅度受到严重抑制,甚至变平坦,总功率大大下降,再灌注后总功率难以恢复,在120min时仅恢复到缺血前的27.39±11.31%,以后即不再进一步恢复,电针组动物缺血10min再灌注后,脑电的恢复明显比对照组快,120min时恢复至缺血前的71.45±16.46%(P<0.01),240min时继续恢复至缺血前的75.27±18.43%。同时电针能明显减轻缺血10min后再灌注24小时的神经原缺血性损伤。结果提示:电针对急性脑缺血引起的神经原损伤具有保护作用,并能促进脑功能的恢复。 相似文献
106.
Background : A retrospective analysis of 103 case records from 1978 to 1996 with a provisional diagnosis of Buerger's disease was undertaken at the Department of Surgery, University of Hong Kong, Queen Mary Hospital. The aim of the study was to elucidate the clinical course and evaluate the results of surgical intervention of Buerger's disease in Hong Kong Chinese people. Methods : Fourteen patients were subsequently excluded from the study because of inability to fulfil our diagnostic criteria. Data on clinical presentation, investigations, indications and results of surgical intervention were reviewed. Sympathectomies and arterial reconstructions were performed on 42 and four patients, respectively, for critical ischaemia or rest pain. Outcome was analysed with respect to the rate of ulcer healing, pattern of recurrence and limb loss. Results : The patients were all young male heavy smokers with a mean age of 36.5 years. The majority of patients (80%) presented with ischaemic ulceration or gangrene. Vascular reconstruction was undertaken in four patients and satisfactory long-term results were obtained in three patients. Sympathectomy was able to relieve symptoms in 87% of operated patients and ischaemic ulceration healed in 2.6 (mean) ± 1.7 (SD) months after the operation. If the patient continued to smoke, surgical intervention did not exempt the patient from a relapse or amputation. Conclusion : Sympathectomy provides short-term pain relief and promotes ulcer healing in patients with Buerger's disease but carries no long-term benefit. Complete abstinence from smoking is the only means of arresting the progression of the disease. 相似文献
107.
作者综述了10年来对Duchenne型肌营养不良症(DMD)的研究概况。主要包括①DMD的临床研究。②血清生化研究表明CK、LDH、Mb是诊断DMD病人和携带者的敏感指标。③心脏无创性检测和肌肉超微结构研究。④部分抗肌萎缩蛋白基因YAC物理图谱,精细限制酶图谱和缺失热区的核苷酸顺序分析,首次发现内含子中AT富集区的同源顺序与DMD断裂有关。⑤抗肌萎缩蛋白的缺失热区疏水肽段存在与否与DMD发病密切相关。 相似文献
108.
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
109.
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
110.
S Kimel L O Svaasand M Hammer-Wilson V Gottfried S Cheng E Svaasand M W Berns 《Lasers in surgery and medicine》1992,12(4):432-440
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