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101.
Eighty patients who had undergone jejunoileal bypass for morbid obesity were examined by ultrasound at their routine follow-up visits to the clinic. Ultrasonographic evidence of intestinal intussusception was found in 15 patients (19%). Two of these patients were asymptomatic. Ultrasonographic findings were confirmed by operation in 6 patients (5 with intussusception, 1 negative).  相似文献   
102.
目的 探讨高频超声检测小儿腹股沟斜疝腹股沟管扩张程度对于选择手术方式的价值。 方法 回顾分析 4 88例施行单纯疝囊高位结扎手术的小儿腹股沟斜疝超声检测的腹股沟管扩张最大内径 ,分组追踪其术后斜疝复发率。 结果 腹股沟管扩张最大内径 >1.5 cm的一组病例术后复发率明显增高。 结论 高频超声检测腹股沟管扩张最大内径 >1.5 cm的小儿腹股沟斜疝有必要行斜疝修补术 ,减少复发率 ,为临床医师提供有价值的客观指标  相似文献   
103.
Prostaglandin E1 (PGE1) was used in renal transplant recipients with living related donors. The drug was given intravenously from day 1 to day 7 after transplantation at a dose of 40 µg/kg twice a day. A total of 45 patients were studied divided into two groups: 25 patients were treated with PGE1 (group B) and the remaining 20 patients did not receive the drug (group A). In group B, 24-h creatinine clearance (Ccr) was 66 ± 12.8 ml/min compared with 40.3 ± 13.4 ml/min in group A on the fifth postoperative day (P < 0.05). Urinary levels of N-acetyl-β-d -glucosaminidase (NAG) and serum levels of platelet factor 4 (PF4) in group B were significantly lower than in group A. On the fourth postoperative day, the urinary excretion of thromboxan B2 (TxB2) in group A was higher than in group B, but not significantly (5.1 ± 3.0 ng/day and 2.8 ± 1.1 ng/day, respectively). Acute rejection occurred in four patients in group B and in 10 patients (40%) in group A. The percentage of Leu2a-positive lymphocytes in group B was higher than in group A. We conclude that postoperative administration of PGE1 improves graft function in kidneys from living related donors.  相似文献   
104.
高强度聚焦超声及其医学应用   总被引:1,自引:0,他引:1  
HIFU技术的研究在国内外已掀起了热潮.到目前为止.HIFU技术已得到广泛的实验和临床支持。本文将对HIFU治疗设备的总体结构做一阐述.并讨论其在医学领域中的应用及发展方向。  相似文献   
105.
The dynamics of the speed of transcranial propagation of ultrasonic impulses has been established in humans. The possibility of detecting the changes in mechanical state of intracranial structures by dynamic measurement of the time of transcranial propagation of ultrasonic impulses (TUPT) has been ascertained for 10 healthy persons and 11 patients with different neurological pathology. The cerebrospinal fluid pressure (CSFP) was simultaneously monitored for 4 of the patients. Spontaneous fluctuations in TUPT and the changes caused by jugular veins, inferior vena cava compression, hyperventilation and temporary retention of breathing were detected for all investigated subjects. Spontaneous TUPT changes in the range of 0.25-0.85 x 10(-4) of initial mean value, which are related with cardiac and respiratory cycles, have been found in healthy persons while in patients they ranged from 0.07 x 10(-4) to 4.5 x 10(-4) of mean time. In healthy persons bilateral jugular vein compression leads to a decrease in TUPT by 1.8-3.0 x 10(-4), while the compression of inferior vena cava gives an increase in TUPT by 1.6-2.6 x 10(-4). Changes in TUPT during these maneuvers in neurological patients were found to be of different amplitude and direction. The rise of CSFP by 8.4-20.2 mmHg (mean 12.4 mmHg) was observed in 4 investigated patients during the compression of jugular veins or during the inferior vena cava compression, while the changes in TUPT obtained during each of such maneuvers were of opposite character. The results suggest that dynamic evaluation of acoustic impedance of intracranial system reflects the changes in the mechanical state of brain parenchyma.  相似文献   
106.
Summary. The increasing spectrum of therapeutic options for tumors of the gastrointestinal tract has resulted in a refinement of the pretherapeutic diagnostic strategies. The diagnostic approach in surgical institutions that are focused on primary surgical resection will therefore be much less sophisticated than in institutions who propose a selective therapeutic approach based on the pretherapeutic tumor stage and prognostic parameters. Pretherapeutic assessment of the depth of tumor infiltration, i. e. the T-category, is essential because most further diagnostic and therapeutic decisions are based on this information. This can today be achieved with a high degree of accuracy by endoscopy and endoscopic ultrasonography. Early T-stages (T1–2) are usually an indication for primary surgical resection and, after exclusion of distant metastases, no further diagnostic studies are required. In patients with locally advanced esophageal, gastric or rectum tumors (T3–4) multimodal therapeutic concepts should be considered. This usually requires additional diagnostic studies. None of the available diagnostic imaging modalities today allows satisfactory pretherapeutic assessment of lymph node metastases. The assumed nodular status should therefore currently not influence therapeutic decisions. Essential is, however, the assessment of distant metastases, since the documentation of distant tumor spread will change the therapeutic approach to a palliative situation. Detailed histologic and molecular-biologic assessment of tumor characteristics is growing in importance. This not only provides therapeutically relevant information regarding tumor grading, but opens the door towards a modern molecular diagnostic approach. It can be expected that in the near future a vast amount of relevant prognostic information can be obtained from endoscopic tumor biopsies, which may soon alter our therapeutic concepts.   相似文献   
107.
目的:探讨门静脉临床病变类型及超声诊断价值,指导临床治疗及预防。方法:通过120例超声诊断门静脉病变分析总结,对门静脉病变进行归纳分类,指导临床治疗及预防。结果:按门脉节段分类门脉病变分为:①门脉属支病变,②门脉主干病变,③门脉分支病变。每一病变又分门脉血流异常,门脉本身病变,门脉外异常影响门脉。并分析部分异常出现的原因及后果,指导预防及治疗。结论:应用彩超可以评价门脉病变性质、部位,部分指导临床治疗。  相似文献   
108.
Skin reactions to irritants assessed by non-invasive bioengineering methods   总被引:3,自引:1,他引:2  
Pathophysiological components of irritant contact dermatitis caused by 3 chemically-different irritants were investigated. 20 healthy volunteers were patch tested with sodium lauryl sulphate, nonanoic acid and hydrochloric acid on the flexor side of the upper arm. The skin response was evaluated after 24, 48 and 96 h by visual scoring and measured by the following bioengineering methods: transepidermal water loss measurement, electrical conductance for measurement of skin hydration, laser Doppler flowmetry for measurement of cutaneous blood flow and 20 MHz ultrasound A-scan for measurement of skin thickness. In spite of homogeneous inflammatory responses, significant differences in the severity of the injury to the skin barrier function caused by the different irritants were found. Also significant differences between irritants were found in the time course of development of maximum irritant reactions. Bioengineering methods indicating inflammatory responses (measurement of blood flow and skin thickness) were helpful in quantifying the irritant response in general, while bioengineering methods indicating epidermal damage (measurement of TEWL and electrical conductance) were helpful in classifying the individual irritants.  相似文献   
109.
经阴道超声诊断子宫内膜癌   总被引:1,自引:0,他引:1  
目的 探讨应用经阴道超声(TVS)诊断绝经前后出血妇女子宫内膜癌的价值。方法 采用彩色多普勒超声诊断仪检测74例阴道异常出血的妇女,其中绝经前28例,绝经后46例,所有患者均取子宫内膜组织行病理对照。结果 TVS检测子宫内膜癌的敏感性、特异性、假阳性率、假阴性率、阳性预测值和阴性预测值,绝经前妇女依次为61.5%,50.0%,14.3%,23.8%,94.1%和54.5%,绝经后妇女依次为97.3%,55.6%,44.4%,2.7%,90.0%和83.0%。结论 TVS检测可作为子宫内膜癌首选的筛查方法,尤其对于绝经后妇女价值更大。  相似文献   
110.
We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound (20 MHz ultrasonic miniprobe; UMP). Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone EIS. The collaterals were divided into two groups: peri‐esophageal collateral veins (peri‐ECVs) and para‐esophageal collateral veins (para‐ECVs). These were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe the peri‐ECVs group than in mild the peri‐ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, UMP findings included a significantly higher incidence of severe peri‐ECVs, a significantly larger diameter of perforating veins compared with patients without recurrence. In conclusion, the presence of severe peri‐ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these UMP abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension.  相似文献   
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