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51.
Priv.-Doz. Dr. V. Nutz M. Peschen 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1992,377(6):372-377
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
52.
目的:观察上腹器官簇移植术实验中血流动力学及血生化变化。方法:杂种猪32只。随机分为供体组和受体组,无肝期行体外静脉转流。测定术中的血流动力学和血生化指标。结果:(1)术中血流动力学在无肝期初期及开放后早期时间内有明显的波动,心输出量、血压、肺动脉压和肺毛细血管楔压下降,心率加快;(2)转流在一定程度上稳定血流动力学;(3)生化变化:开放前行肝冲洗的8例,血钾仅轻度升高;未作冲洗的6例,则血钾明显升高;(4)开放后均有不同程度的代谢性酸中毒。结论:上腹器官簇移植术,机体血流动力学及血生化均有改变,特别是在肝移植阶段明显。其它器官移植期处理也应考虑肝移植后续作用的影响。 相似文献
53.
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
54.
本文报道了北京市房山区1147人血压家庭相似性研究结果。亲子代回归法得出的血压遗传度估计值为0.42(收缩压)和0.48(舒张压),全同胞相关法得出的血压遗传度估计值为0.37(收缩压)和0.53(舒张压)。两种方法得出的遗传度估计值相差不大,这一结果提示血压的遗传符合加性多基因模型。本文报道的血压遗传度没有区分遗传效应和共同生活环境效应。此外,本文强调了将血压作为数量性状采用数量遗传学方法进行遗传度估计的合理性和有效性。 相似文献
55.
Hans Rommelspacher Lutz G. Schmidt Torsten May 《Alcoholism, clinical and experimental research》1991,15(3):553-559
Based on the hypothesis that condensation products of neurotransmitters with aldehydes are involved in the pathogenesis of alcoholism, aromatic beta-carbolines (norharman and harman) were measured in the blood plasma of alcoholics and nonalcoholics. The identity of the extracted compounds was confirmed by various elution conditions of the high performance liquid chromatography (HPLC), newly developed radioreceptor assays, and the mass spectrum of norharman. The levels of norharman and harman in nonalcoholics were unchanged after a load with ethanol (1 g/kg body weight). The norharman levels of the alcoholics were significantly higher than that of the nonalcoholic controls (99.5 +/- 26.6 pg/ml vs. 26.9 +/- 10.7 pg/ml; p less than 0.001) and did not change significantly during a 3-week detoxication period. In the subgroup of alcoholics with delirium or hallucinosis, a slight increase of norharman during detoxication could be detected while in alcoholics with vegetative withdrawal symptoms norharman levels dropped slightly over time (p = 0.07). No difference was found with respect to harman between nonalcoholics and alcoholics. These results suggest disturbed regulatory processes in the formation and/or metabolism of norharman in alcoholics. Further investigations are needed to reveal a possible marker function of norharman in alcoholic patients. 相似文献
56.
A. Rudehill J. M. Lundberg A. Sollevi P. Hjemdahl 《Acta anaesthesiologica Scandinavica》1987,31(2):132-138
Graded increases of intracranial pressure (ICP) in anaesthetized pigs induced elevations of plasma levels of neuropeptide Y (NPY)-like immunoreactivity (LI) and catecholamines, simultaneously with hypertension and tachycardia. Plasma adrenaline (ADR) increased at a lower ICP-level than did the plasma levels of noradrenaline (NA) and NPY-LI. At the maximal ICP elevation, 22.9 kPa (172 mmHg), plasma NPY-LI was increased about 10-fold, from 48 +/- 8 pmol/l in the basal state, while NA and ADR concentrations increased more than 100-fold. At this maximal ICP-level the plasma levels of NPY-LI were correlated to the concentrations of both NA (r = 0.87, P less than 0.01) and ADR (r = 0.92, P less than 0.001). Plasma NPY-LI continued to increase to about 1000 pmol/l, 10 min after the maximal elevation of ICP was discontinued, while the catecholamines then had declined considerably. A slight cardiac release of NPY-LI was observed at the maximal elevation of ICP. The half-life of NPY-LI in plasma was about 6 min upon systemic infusion. At plasma levels similar to those obtained upon maximal ICP elevation, exogenous NPY caused slight vasoconstriction in the spleen and skeletal muscle, but had no effects on coronary blood flow or systemic blood pressure. This suggests that NPY mainly exerts local actions after release from nerve endings, while levels of circulating NPY in plasma must be very high to influence blood flow in some organs. It is concluded that elevation of ICP results in hypertension and tachycardia related to elevated plasma levels of NPY-LI and catecholamines.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
57.
讨论了一系列N-酰化壳聚糖膜的抗张强度、透水性、VB_(12)的透过性、透氧性以及血液相容性。N-已酰化壳聚糖膜具有良好的血液相容性。在制膜过程中,加入分子量为1500的聚乙二醇为致孔剂,则可使N-己酰化壳聚糖膜的渗透性有较大提高。同时保持较好的血液相容性和强度。 相似文献
58.
These studies demonstrate the presence of pontomedullary areas in the rat brainstem which, when stimulated electrically, serve to set postural muscle tone in the hindlimbs. Low amplitude stimulation of the dorsal tegmental field (DTF) was found to inhibit postural muscle tone and, in some rats, was found to decrease mean arterial pressure. Low amplitude stimulation of the ventral tegmental field (VTF) was found to increase postural muscle tone and, in all cases tested, was found to increase mean arterial pressure. 相似文献
59.
60.
The authors report a spiny dogfish (Squalus cubensis/megalops group) sting of a professional fisherman. He was injured on the left hand by the spine anterior to the fish's dorsal fin and manifested local edema, erythema, and excruciating pain for 6 h. Sharks of the genus Squalus megalops/cubensis and Squalus acanthias are found throughout the world; they have two spines in front of their dorsal fins and channels with a whitish mass containing large vacuolated cells which secrete venom. The Squalus genus has a complex taxonomy; the species involved in this injury belongs to the megalops/cubensis group. A detailed taxonomic and toxinological study on the Squalus genus is important and would complement other work on these fish, especially as stings in humans are very rare and not fully understood. 相似文献