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81.
目的探讨肺炎性假瘤的临床与X线误诊原因;方法依据临床与X线资料分析;结果均有不同程度的呼吸道症状,有14例痰中带血丝。肿块直径小于4cm11例,密度高而均匀,边缘光整,误诊为肺良性肿瘤。肿块直径大于4cm13例,密度不太均,边缘有分叶或有毛刺,误诊为肺癌;结论临床上多无急慢性感染症状,本病与其他占位性病变极相似,缺少特征,对本病缺乏认识是导致误诊的主要原因。肿块邻近胸膜,边缘出现尖角征,动态变化缓慢这3点对提高正确诊断率有独特的价值。  相似文献   
82.
目的 对111眼屈光范围球镜在-3.00 ̄-17.00D及柱镜在-0.50D ̄-4.50D范围的患者进行了PRK术后的分析。方法 采用美国VISX20/20B准分子激光系统的最新软件包进行角膜切削,并行术前后的主客观验光及角膜透明度检查。结果与结论 准分子激光PRK术是目前理想的屈光手术之一,特别对于中低度近视尤为适合,对高度近视则其预见性稳定性较差,并发症的发生并未成为影响术后效果的主要因素。  相似文献   
83.
Both filtering surgery with Mitomycin-C and diode laser cyclophotocoagulation have proved to be effective alternatives in cases of glaucoma with poor surgical prognosis. The right eyes of 40 pigmented rabbits were randomly divided into 2 groups: Mitomycin-C group underwent filtering surgery with application of 0.4 mg/ml of Mitomycin-C whereas the diode laser (DL) group received 15 applications of 1.8 J (1800 mW. 1000 ms) distributed in 270°. Mean IOP showed statistical differences in two periods between days 3–13 and 45–60 — Mann-Whitney U test — with a higher IOP lowering in the DL group. The comparison of IOP survival curves (Log-Rank test) was not significant p = 0.070809. Ocular hypertension, hyphema and inflammatory signs were higher in the DL group, both in short and long term, but in terms of statistical significance only ocular hypertension showed differences p = 0.00011717 - Fisher exact test. Microscopic examination revealed patent sclerostomies in 60% of the MMC group eyes with different grades of fibroblastic proliferation. In the DL group we observed necrosis of the sclieral stroma and of the pigmented and unpigmented ciliary epithelium, with signs of thermal coagulation of the ciliary stroma and of the stromal vasculature. We must point out that the treatment with laser has proved to be more effective although both treatments showed very acceptable IOP lowering until 2 months after the surgery.  相似文献   
84.
Haemostasis was effected in vessels of melanin-rich (MR: choroid) and melanin-free (MF: mesentery) rabbit tissue irradiated with a cw-Nd: YAG laser. The following parameters were employed: - pulse duration: 200 ms (MR) and 100ms (MF); focal spot diameter: 200 m (MR) and 80 m (MF); pulse energies: 100–250 mJ (MR) and 0.5-1J (MF); irradiances: 1.6–4.0kWcm–2 (MR) and 1–2 × 102kWcm2 (MF). In melanin-rich tissue, laser energy is absorbed principally by melanin granules contained within the stromal melanocytes. The heat generated in these structures radiates into the surrounding tissue where it is dissipated. The damage thus incurred by the endothelium of blood vessels encompassed within this field triggers the haemostatic mechanism whereby blood flow is arrested. This effect is realized by the formation of an occluding plug of platelets, which is stabilized by the deposition of fibrin, particularly in capillaries, and to a lesser degree in larger vessels of the vascular lamina. In melanin-free tissue, haemoglobin serves as the primary site of energy absorption, which is thus shifted from the stroma to the vessel lumen. Irradiation of vessels in such tissue leads to thermocoagulation of plasma proteins and consequent stasis of blood flow.  相似文献   
85.
Summary The uptake and localisation of O-(-hy-droxyethyl)-rutosides (HR) in the venous wall was studied in 8 patients undergoing crossectomy for a varicose long saphenous vein. The fluorescence of cross-sections of the vein wall was measured by laser scanning microscopy, based on the autofluorescence of HR. Four patients (treated group) received 2 × 1.5 g HR IV before surgery, and four (untreated patients) served as controls.Uptake of HR into the veins from treated patients was seen, with a mean fluorescence intensity of 80.9 units compared to 49.4 units in the untreated veins. The increase in fluorescence was clearly demarcated on the endothelial side of the vein wall.It is concluded that HR passes into the vascular wall, where it is localised in the endothelial and sub-endothelial areas.  相似文献   
86.
A solitary hepatic metastasis is amenable to surgery. However, if surgery is contraindicated or if multiple lesions are present in both liver lobes, other treatment modalities have to be considered. We compared the effect of interstitial laser hyperthermia with damage caused by alcoholization. Six anaesthetized beagle dogs were studied. Three animals were treated with laser hyperthermia. A bare laser fibre (400m diameter) was introduced through a 17-gauge needle, length 170 mm, positioned into the liver under real time ultrasonographic guidance. Lesions were produced by continuous 500-s exposure of 1W YAG laser (Medilas MBB 40N) power. Three dogs were subjected to an injection of 4 ml of 98% pure ethanol into the liver through the same needle system. Two days after the procedure the animals were killed and the livers examined. The surface of the livers treated with the YAG laser were entirely normal; superficial lesions were, however, clearly visible. Laserinduced lesions were well reproducible, clearly demarcated, roughly spherical with a mean diameter of 1.01±0.23 cm (n=16). In contrast, the dogs treated with alcohol had free intraperitoneal serohaemorrhagic fluid and the surface of the liver was diffusely abnormal. The lesions had a more or less cylindrical shape, 1.22±0.43 cm on 0.40±0.10 cm (n=12) although exact measurement was often difficult. The border of the lesions was irregular and there was a clear necrotic zone along the puncture track. On microscopic examination the laser-induced lesions consisted of a central evaporation area, a zone of carbonized material and an outer zone of coagulation necrosis. The alcohol-induced lesions were characterized by both fixation necrosis and coagulative necrosis but surprisingly, there was also necrosis present at a distance of the lesions extending along the centrilobular and even portal veins. These data show that laser-induced interstitial necrosis in the liver is better controlled and more reproducible than necrosis induced by injection of pure ethanol. Moreover, pure ethanol may cause damage to the liver surface and even at a distance of the injection site.  相似文献   
87.
Summary Sixty patients with raised intracranial pressure and lowered attenuation areas around the lateral ventricles (periventricular lucency, PVL) on CT scanning were reviewed, and compared with a control group of 90 similar patients who did not have PVL. It was confirmed that PVL tends to occur in patients with acute or subacute obstructive hydrocephalus due to a tumour, and is more common in the presence of papilloedema and/or a decreased level of consciousness. Patients with very dilated lateral ventricles did not in general have PVL, but it was frequently seen in association with diastasis of the sutures. Twelve patients with PVL had no other clinical or radiological indication of raised intracranial pressure. Comparison with the control cases did not reveal any reason as to why some patients should develop PVL while others did not.  相似文献   
88.
Summary In 11 mongrel dogs both kidneys have been subjected to a 2 h ischaemic period. One kidney was cooled by perfusing the renal artery at 4°C while the contralateral normothermic kidney was clamped for 2 h. Studying the renal blood flow using the Xenon wash out technique, sequential renal scanning and angiography, marked differences between hypo- and normothermic ischaemia kidneys were observed. One or two hours following hypothermic perfusion a marked decrease of blood flow in the first compartment and vasoconstriction was evident, while within this period following normothermic ischaemia an enhanced renal blood flow was observed. After 24 h renal blood flow and renal function tested by 131I-Hippuran clearance returned to normal values. Angiographic studies corresponded to the preoperative findings. In contrast, normothermic ischaemia kidneys showed a decreased renal blood flow, impairment of kidney function in isotope studies and pathological angiographic changes.Supported by Deutsche Forschungsgemeinschaft  相似文献   
89.
家兔血清中黄芩苷的薄层扫描法测定及药动学参数   总被引:4,自引:0,他引:4  
采用薄层扫描法测定家兔血清中的黄芩甙及在兔体内的药物动力学参数。结果显示血清药物浓度在0.5~25μg/ml范围内线性关系良好,体内药物动力学呈开放性二室模型。并通过回收率试验确定了方法的准确性。  相似文献   
90.
茎突CT薄层冠状扫描在诊断茎突过长综合征中的价值   总被引:1,自引:2,他引:1  
目的 探讨“一点一线垂直法”茎突CT薄层冠状扫描在诊断茎突过长中的价值。方法测量72例双侧茎突的长度、方位、形态、厚度、尖端与咽侧壁距离,总结茎突过长病人的临床症状与诊断。 结果 ①41例67侧长度超过3.0cm,符合茎突过长的诊断;②12例12侧茎突虽未超过3.0cm(均在2.5~2.9cm),且茎突方位角>20°、末端与咽侧壁的距离<20mm,并有临床症状的应考虑茎突过长综合征;③按茎突的形态进行分型:锥型(分直锥、弧锥),束状型,分节型,发育不良型。其中分节型与临床症状有密切关系。结论 ①茎突CT薄层冠状扫描能清晰显示茎突的长度、形态、厚度、末端与咽侧壁距离,是诊断茎突过长的一种可靠方法;②“一点一线垂直法”茎突CT薄层冠状扫描无需进行图像重建,可操作性强、简捷易行、便于推广。  相似文献   
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