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121.
Summary A duplex ultrasound system was used to examine the blood flow of the common femoral artery in ten young patients with fractures of the lower extremities. Two patients had fractures of both legs. In eight patients the blood flow in the injuried leg was comparable with that in the not injured leg. The flow alterations were measured on 3–7 different days over a period of 6–224 days after trauma. All patients showed a significant (to twice or three times that before injury) increase in blood flow in the injured leg a few days after trauma and/or operation, whereas the blood flow in the uninjured leg remained the same or even decreased a little. In the case of undisturbed fracture healing the change in blood flow disappeared within 8–12 weeks, corresponding to fracture consolidation. When fracture healing was delayed and/or further operations on the injured leg were necessary, the blood flow was increased for much longer. The hemodynamics of an injured extremity are compared with those reported elsewhere in the literature. The increased demand for oxygen or energy can explain the changes only in part. Another function of the reflective increase in blood flow could be the temperature increase in the extremity.
Doppler-sonographische durchblutungsmessungen der unteren extremität des menschenII. Hämodynamik nach trauma und operation
Zusammenfassung Mittels Doppler-sonographischer Durchblutungsmessung wurde die Hämodynamik der verletzten Extremität an 10 jungen Patienten mit Frakturen der unteren Extremität untersucht. Bei 8 Patienten konnte die Durchblutung des verletzten Beins mit der unverletzten Gegenseite verglichen werden. Die Messungen erfolgten an 3–7 verschiedenen Tagen in einem Zeitraum von 6–224 Tagen nach dem Unfall. An allen verletzten Extremitäten steigt die Durchblutung wenige Tage nach dem Unfall und/oder der Operation deutlich um das 2- bis 3fache an, während die Durchblutung des unverletzten Beins niedrig bleibt. Bei einem ungestörten klinischen Verlauf sinkt die Durchblutung in 8–12 Wochen wieder. Heilungsstörungen und weitere Operationen an dem Bein verzögern diese Normalisierung deutlich. Diese Ergebnisse werden mit anderen Untersuchungen der Literatur verglichen. Ursache und Funktion der hämodynamischen Änderungen könnte u. a. in einer reflektorischen Temperaturerhöhung zu sehen sein.
  相似文献   
122.
The relationship between internal jugular vein diameter as measured with an ultrasound imaging machine (SiteRite, Dymax) and external jugular vein diameter was studied in 50 anaesthetised patients undergoing elective cardiac surgery. There was an inverse correlation between external jugular vein diameter and internal jugular vein diameter ( r  = −0.47, p < 0.001). All patients with an external jugular vein diameter of 7 mm or greater had an internal jugular vein diameter of less than 15 mm. No patient with an external jugular vein diameter of less than 7 mm had an internal jugular vein diameter of less than 20 mm. No other patient dimension (height, weight, body mass index, neck circumference) predicted internal jugular vein size. These results suggest that a large external jugular vein (i.e. 7 mm or greater in external diameter) may be associated with a small internal jugular vein. A size 5.0-mm internal diameter tracheal tube may be used to provide a rapid assessment of external jugular vein diameter.  相似文献   
123.
癌胚抗原的测定及意义   总被引:1,自引:0,他引:1  
癌胚抗原(carcinoembryonicantigen,CEA)作为肿瘤标志物之一,近年在肿瘤,特别是恶性肿瘤的诊断、监测和判断预后等方面得到了广泛地应用,是较灵敏和可靠的指标.本文就CEA的测定、意义及不同标本测定的差别等作一综述  相似文献   
124.
125.
Summary: We studied the effect of antiepileptic drugs (AEDs) on internal carotid artery (ICA) blood flow velocity, as an index of total cerebral blood flow (CBF). The subjects were 45 newly diagnosed children with febrile convulsion or epilepsy who were seizure-free for a period long enough not to affect the results. They had no neurologic deficit, received fixed monotherapy, and were examined by a noninvasive Doppler ultrasound method, in comparisonwith 13 age-matched normal volunteers with no AED. In 30 patients, the measurements were performed before and after AED administration [10 with phenobarbital (PB), 10 with carbamazepine (CBZ), and 10 with valproate (VPA)], and performed before and after AED discontinuation in the remaining 15 patients (all with PB). Normal volunteers underwent the two consecutive examinations with a mean interval equal to that of the entire patient group, and there was no difference in velocity values between the measurements. In patients receiving CBZ or VPA, a significant reduction was noted in blood flow velocity after drug administration. Although velocity values in the patients receiving PB did not change after drug administration, they were significantly increased after complete discontinuation. In the present study, a slight but significant reduction in CBF caused by AED administration at therapeutic doses in children was suggested.  相似文献   
126.
Laparoscopic cryosurgery for hepatic tumors   总被引:2,自引:0,他引:2  
Background: Hepatic cryosurgery has been shown to be a safe technique that may be well suited to a laparoscopic approach. Methods: The technical feasibility and safety of laparoscopic cryosurgery was explored first in a pig model. Thereafter we performed the first successful case of laparoscopic hepatic cryosurgery at our institution. Results: In the animal model, we found that it is possible to safely identify, target, and cryoablate specific lesions in the liver. Temperature in the peritoneal cavity remained above 35°C, and pathologic examination of the abdominal wall around the cryoprobe site revealed no damage. We also successfully treated a 62-year-old man with a metastatic colorectal carcinoma deep in the right lobe of the liver with laparoscopic cryosurgery using a transpleural approach. Conclusion: We conclude that laparoscopic cryosurgery is feasible for lesions anywhere in the liver. For lesions high on the dome of the liver, a transpleural approach may provide better access.  相似文献   
127.
Marker enzymes of Sertoli and germ cells were estimated to study the mechanism of action of antispermatogenic compound CDRI 84/35 in adult male rat testis. Animals were killed after 22, 41, and 64 days of treatment with antispermatogenic dose of CDRI 84/35 in order to evaluate the effect of the compound on spermatid, spermatocyte, and spermatogonial stages, respectively. Studies were also extended to a recovery period of 90 days. Results indicate a direction action of the compound on germ cells, with no apparent effect on Sertoli cells. Studies also show a massive depletion of postmeiotic germ cells after the treatment, with some damage to premeiotic germ cells as well. Reversibility of the compound was partial, with the marker enzymes of pre- and postmeiotic germ cells not being restored to control levels after withdrawal of treatment.  相似文献   
128.
对126列原发性肝癌与37例转移性肝癌介入治疗前均进行了B超、CT与数字减影血管造影(DSA)检查。DSA显示原发性肝癌多数血供丰富,而转移性肝癌以少血供者为主;CT显示小病灶的敏感性稍差,病灶的密度和均匀性与血供多少有一定关系,但特异性不高,而病灶的增强次应与血供关系密切,多血供者中95%有显示的增强效应,少血供者仅占4.7%;B超所示病灶的回声高低与血供亦有一定关系,但特异性稍差。结果表明,D  相似文献   
129.
颈动脉粥样硬化及其相关因素的探讨   总被引:2,自引:0,他引:2  
目的:探讨颈动脉粥样硬化与相关危险因素的关系。方法:对200例研究对象的颈总动脉内中膜厚度(IMT)和颈动脉粥样硬化斑块进行超声检测,根据TMT分为IMT≤0.99mm组和IMT≥1.00mm组,并记录胆固醇(TC)、甘油三脂(TG)、高密度脂蛋白(HDL-c)、低密度脂蛋白(LDL-c)、载脂蛋白AI(APOAI)、载脂蛋白B_(100)(APOB_(100))、脂蛋白(α)[LP(α)]、纤维蛋白原(Fbg)、血糖(BG)、血压(BP)、体重指数(BMI)、吸烟指数及年龄等指标。结果:随着IMT增厚,颈动脉粥样硬化斑块发生率增加(P<0.01),IMT与TC、LDL-c、APOB_(100)、LP(α)、Fbg、SBP、吸烟指数及年龄呈明显正相关(P<0.05~0.01)。结论:颈动脉粥样硬化与TC、LDL-c、APOB_(100)、LP(α)、Fbg、SBP及嗜烟和年龄密切相关。定期超声监测颈动脉及检查相应危险因素对防治颈动脉粥样硬化有一定的实用参考价值。  相似文献   
130.
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   
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