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101.
Dissection of an adult male cadaver revealed an absence of the left inferior thyroid artery; its usual area of distribution to the thyroid gland was supplied by the right inferior thyroid artery. Absence of the left inferior thyroid artery occurs in 1-6% of cases. The inferior thyroid artery arises commonly from the thyrocervical trunk, passes posterior to the carotid sheath and supplies the inferior pole of the corresponding lobe of the thyroid gland; its branches can course anterior or posterior to or between branches of the recurrent laryngeal nerve. During thyroid surgery it is imperative to identify the relationship of the inferior thyroid artery to the recurrent laryngeal nerve or to establish its absence because injury to the nerve can be a major complication; awareness of significant variations of the surgical anatomy of the thyroid gland is vital for preserving the integrity of important structures.  相似文献   
102.
The effects of oestrogen therapy and of orchidectomy on coronarystauts, as reflected by exercise ECG-testing before and afteryear of tretment, were assessed in a randomized study of patients(N=100) prostatic cancer. Oestrogen was given as polyestradiolphosphate 80 mg i.m. per month in combination with 150 µgor in pre-traetment exercise test results Twelve months afterstart of therapy the oestrogen group showed a significantlygreater depression of the ST-segment during maximal exercisein leads CH2 (P<0.0005) and CH5)P<0.01) compared withthe pre-treatment depression. Twenty-five per cent (N=13) ofthe patients in the oestrogen group suffered cardiovascularcomplications during the yera the of therapy, whereas no suchcomplications were observed in the orchidectomy group. However,even the patients in the oestrogen group who had not sufferedcardiovascular complications had significantly greater depressionsof the ST-segment during exercise both in lead CH2 (P<0.0005)and in CH5 (P<0.05). There was no significant change in theST-segment level in the orchidectomy group twelve months aftersurgery. In summary, we found of an induction of myocardialishaemia during treatment with exogenous oestrogens at low dosagein patients with prostatic. This deleterious effect of oestrogenon the coronary status argues against oestrogen therapy, sinceoedtrogen has not been shown to be more beneficial than orhidectomyagainst prostatic carcinoma.  相似文献   
103.
Summary Anterior displacement of the mandible (ADM) was performed in 34 patients undergoing surgery for malformations or atheromatous lesions of the distal segment of the extracranial internal carotid artery (ICA). This procedure greatly facilitates surgical access to the upper cervical region and has several advantages over mandibulotomy-mandibulectomy, namely: A shorter operating time, sparing of the inferior alveolar nerve and of the mandibular branch of cranial nerve VII, with no need for post-operative immobilization of the mandible. ADM permits the correction of ICA lesions extending as far as the first cervical vertebra. For lesions extending into the carotid canal ADM needs to be supplemented by various other procedures via the base of the skull.  相似文献   
104.
Summary Recent observation of one patient suffering from dysphagia lusoria has suggested critical review of treatment of the symptomatic aberrant right subclavian artery. Surgical correction of such an anomaly is difficult and may produce serious complications, and is not always successful. Endoscopic dilatation of the oesophageal stricture, even though it might only produce temporary relief of dysphagia, represents a valid therapeutical alternative because of its favourable cost/benefit ratio, low incidence of complications and patient acceptability.  相似文献   
105.
Regional cerebral blood flow after occlusion of the middle cerebral artery   总被引:3,自引:0,他引:3  
Occlusions of the middle cerebral artery (MCA) are mostly of embolic origin (appr. 80%) and give rise to about one third of all ischemic strokes, most of these being major strokes. MCA occlusions lasting for less than 1/2 h are tolerated without occurrence of permanent tissue damage. Occlusions lasting between 1/2 h to 4-8 h lead to permanent tissue damage and neurological deficits that are proportional to the duration of occlusion. Maximal tissue damage is obtained after 4-8 h occlusion. A cerebral blood flow of 8-23 ml/100 gr/min is sufficient for cellular viability but insufficient for normal tissue function ("ischemic penumbra"). Cellular function is completely abolished in the interval 8-16 ml/100 gr/min and flow at that level is tolerated only for 1-3 h before neuronal death ensues. In the interval 18-23 ml/100 gr/min there is some functional activity although it is reduced. Experimental and clinical evidence suggests that flow in this interval may be tolerated for several days, months or even longer ("chronic ischemic penumbra"). After MCA occlusion the blood flow falls below 8 ml/100 gr/min in most cases and permanent MCA occlusion always leads to relatively large areas of frank infarction. The ischemic infarcts may be surrounded by collaterally perfused areas where the blood flow is pressure-dependent (impaired autoregulation) and quite commonly insufficient for normal neuronal function (below 23 ml/100 gr/min). Such collaterally perfused areas may include a "chronic ischemic penumbra". Emboli causing MCA occlusions commonly disintegrate and/or migrate more peripherally within the first few weeks post stroke. This leads to reperfusion and changes of ischemic infarcts into hyperemic infarcts where flow is severely increased. The vascular reactivity is completely abolished in hyperemic infarcts and the hyperemic state lasts for about two weeks. Probably, anemic infarcts are equivalent to ischemic infarcts while the hemorrhagic variety is equivalent to hyperemic infarcts. The "partial infarct" with selective neuronal necrosis occurs in experimental animals after MCA occlusions of less than four h but not after permanent MCA occlusion. The significance of partial infarction in human stroke is not clarified. The extent of irreversible tissue damage can be reduced only if therapy sets in within 4-8 h after the occlusion. If a "chronic penumbra" exists the extension of reversible tissue damage can be reduced if therapy aimed at increasing the blood flow in the penumbra sets in within weeks or even months after the stroke.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
106.
Summary The interaction between rauwolscine and angiotensin II was investigated in the isolated mesenteric artery of the rabbit. Rauwolscine, known as an antagonist at 2-adrenoceptors, did not induce contraction itself but interacted with angiotensin to produce a facilitated response of the vascular tissue. In the presence of rauwolscine, the contractile response of the tissue to angiotensin was markedly enhanced. The degree of facilitation appeared to be dependent on the rauwolscine concentration used rather than that of angiotensin. Moreover, rauwolscine induced a concentration-dependent increase in tension (pD2=6.8) in the presence of even subcontractile concentrations of angiotensin (10–10 mol/l). This effect was not attributable to an indirect action involving presynaptic catecholamines, as revealed by the use of tissue strips from animals pretreated with reserpine or after chemical sympathectomy. Furthermore, an interaction via the prostaglandin system was excluded by negative results obtained with indomethacin. The agonistic effect of rauwolscine was significantly attenuated by phentolamine (1/2) but not by prazosin (1) or phenoxybenzamine when applied for only a short time. The 2-antagonist BDF 6143 behaved like rauwolscine whereas the 1-antagonist corynanthine, a stereoisomer of rauwolscine, did not. The results indicate that the rauwolscine effect is mediated by a receptor with 2-characteristics. In general, angiotensin appears to interfere with some process which determines the expression of a drug's intrinsic effect.This study was supported by a grant of the Deutsche Forschungsgemeinschaft  相似文献   
107.
肺癌支气管动脉灌注化疗并发症的防治   总被引:1,自引:0,他引:1  
目的 :探讨肺癌支气管脉灌注化疗 (BAI)并发症产生原因及防治措施。方法 :中晚期肺癌 38例行BAI6 2例次 ,15例次出现并发症。结果 :恶心 ,呕吐 8例次 ,局部皮损 3例次 ,脊髓损伤 2例次。经积极治疗 ,以上并发症均得以控制。结论 :BAI可出现不同并发症 ,应注意预防 ,积极处理  相似文献   
108.
目的观察髂内动脉灌注化疗联合手术治疗膀胱癌的疗效。方法对32例中晚期膀胱癌先行介入治疗,再手术切除。结果32例膀胱癌完全缓解(CR)率为71.9%。结论介入治疗中晚期膀胱的手术提供了良好基础,对一部分原本行扩大切除术甚至全切的患实行单纯部分切除术,从而保留了膀胱生理功能,有助于提高患生活质量,延长生命。  相似文献   
109.
目的 探讨植物有效成分蜕皮甾酮(ecdysteron,EDS)对心肌梗死有益作用,并探讨其机制。方法 采用冠状动脉左前降支结扎致大鼠心肌梗死模型,ip EDS,连续7d。测定血清肌酸磷酸激酶(CPK)、谷草转氨酶(GOT)、乳酸脱氢酶(LDH)活性、心肌梗死面积、冠状动脉血清、毛细血管密度及血管内皮生长因子(VEGF)的表达量。结果 0.5,5,50mg/kgEDS能剂量能依赖地影响大鼠血清CPK、GOT、LDH活性,以5mg/kg剂量的EDS降低心肌酶谱为最佳。5mg/kgEDS能明显减少心肌梗死面积、增加冠状动脉血流量、毛细血管密度和VEGF表达量。结论 EDS能减轻冠状动脉结扎致心肌梗死,机制在于促进VEGF的表达和毛细血管再生及增加冠状动脉血流量。  相似文献   
110.
Introduction and objectivesPreoperative renal artery embolization (PRAE) for large renal masses may be performed prior to nephrectomy in order to simplify the procedure and reduce intraoperative bleeding. The objective of this work is to determine the role of PRAE on intraoperative bleeding and postoperative complications in left renal tumors with tumor thrombus limited to the left renal vein (level 0).Material and methodsRetrospective analysis to evaluate 46 patients who underwent left radical nephrectomy and thrombectomy for the treatment of renal cell carcinoma with level 0 tumor thrombus during the period 1990-2020. PRAE was limited to those cases in which surgical access to the main renal artery was presumed a priori difficult in the preoperative imaging study (n = 9; 19.6%). Intraoperative bleeding was estimated based on the perioperative transfusion rate, and postoperative complications were categorized according to the Clavien-Dindo classification. The Chi-squared test was used for comparisons. A multivariate analysis was performed to identify predictors of transfusion and complications.ResultsThere were no significant differences in the overall complication rate (11.1% vs. 32.4%, P = .19), major complication rate (0% vs.8.1%, P = .51), or transfusion rate (11.1% vs. 19%, P = .49) between both groups (PRAE vs. non-PRAE). In the multivariate analysis, PRAE did not behave as a predictor of complications (OR:0.11, 95%CI 0.01-2.86; P = .18) nor transfusion (OR:0.46, 95%CI 0.02-7.38;P = .58).ConclusionsIn our study on left renal cell carcinomas with level 0 tumor thrombus and difficult access to the main renal artery, PRAE was not associated with increased bleeding or postoperative complications, and it did not behave as an independent predictor of these variables. Therefore, it could be used as a preoperative maneuver to facilitate vascular management in selected cases.  相似文献   
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