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51.
逆行灌注心脏不停跳心肌保护的实验研究   总被引:2,自引:1,他引:1  
目的:探讨逆行灌注心脏不停跳心肌保护的效果。方法:中国大白兔32只随机分为4组,每组8只,A组(对照组),B组(心脏不停跳组,血温34℃),C组(温血心脏麻痹液组,血温34℃),D组(冷血心脏麻痹液组,血温4℃)。采用离体兔心左室做功模型,经冠状静脉窦逆行灌注稀释血液或血停搏液60min。比较观察心功能、冠脉排出液心肌酶谱、心肌组织乳酸、心肌细胞内游离钙浓度、心肌细胞膜ATP酶活性、心肌细胞膜脂质过氧化产物丙二醛含量的变化。结果:B组心功能恢复、心肌细胞膜ATP酶活性显著优于C组和D组,C组优于D组;B组心肌酶漏出、乳酸生成量、心肌细胞内游离钙浓度、心肌细胞膜丙二醛(MDA)含量低于C组和D组,C组低于D组。结论:常温氧合血逆灌心脏不停跳良好的心肌保护效果与其减轻自由基损伤,较好地保持细胞内外Ca^2 平衡,减轻细胞内钙超载,保护细胞膜酶功能有关。  相似文献   
52.
Retrograde transport of the fluorescent tracer True Blue was used in combination with immunohistochemical staining of dopamine-beta-hydroxylase (a marker protein for noradrenergic neurons) to determine the origin of noradrenergic projections to three cranial nerve nuclei: 1) the motor nucleus of the trigeminal nerve, 2) the motor nucleus of the facial nerve, and 3) the spinal trigeminal nucleus pars interpolaris. Noradrenergic cells in the rat brainstem were divided into subgroups and their numbers were determined in serial sections stained with an antiserum to rat dopamine-beta-hydroxylase. Following tracer injections into the three brainstem nuclei, retrogradely labeled noradrenergic neurons were counted and the percentage of True Blue-labeled noradrenergic cells in each subgroup was calculated. Injections of tracer into the three cranial nerve nuclei resulted in distinctly different labeling patterns of noradrenergic cells. Of the total number of norepinephrine neurons projecting to the motor nucleus of the trigeminal nerve, 68% were observed within the A7 cell group; 75% of those innervating the motor nucleus of the facial nerve were found in the A5 cell group, and 65% of those projecting to the spinal trigeminal nucleus pars interpolaris were present in the locus ceruleus and subceruleus. These findings indicate that norepinephrine cells in the rat brainstem do not constitute a homogeneous population of cells but that several discrete systems can be identified that differ not only in topography but also in the terminal distribution of their axons. This combined retrograde transport-immunohistochemical study reveals a much higher degree of topographic order in the projections of norepinephrine neurons than has previously been recognized. The observation of differential projections of noradrenergic subgroups argues against the notion of a global influence of these cells over functionally diverse areas of the brainstem.  相似文献   
53.
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   
54.
The role of endoscopic extraperitoneal herniorrhaphy (EEPH) in the management of giant scrotal hernias has not been well defined, and the technical details relating to operations on such hernias have not been described. We present our experience with 17 patients undergoing repair of giant scrotal hernias. Foley catheter bladder decompression was routinely employed. The Retzius space was developed early in the procedure and hernia sac contents were reduced in all cases. The inferior epigastric vessels were likewise divided in all patients. The average operative time was 76 min and all patients were discharged home the same day. There have been no recurrences on follow-up. There was no mortality, and morbidity was limited to seroma formation in two patients. We conclude that with certain technical modifications, EEPH can be safely employed for the treatment of giant scrotal hernias. Received: 7 May 1996/Accepted: 12 July 1996  相似文献   
55.
内镜鼻胆管引流术在腹腔镜和开腹胆总管探查术中的应用   总被引:10,自引:7,他引:3  
目的 评价内镜鼻胆管引流术 (Endoscopicnasobiliarydrainage ,ENBD)配合腹腔镜和常规开腹手术治疗胆总管结石的疗效。 方法 回顾分析 1997年 1月~ 2 0 0 1年 7月应用ENBD配合完成腹腔镜胆总管探查、I期缝合术 4 4例及开腹胆总管探查、I期缝合术 34例。 结果  78例均手术成功 ,术后无胆漏、胆道出血、胆管炎等并发症。术中结石取净率 10 0 % (78 78)。术后住院时间 :腹腔镜组为 (6 2±1 3)d ,开腹组为 (7 4± 2 1)d。随访 5 7例 ,时间 (1~ 4 5 )年 ,平均 2 6年 ,腹部彩色B超检查无胆管狭窄及结石复发。 结论 ENBD配合腹腔镜和开腹胆总管探查取石、胆总管I期缝合术安全、可靠。  相似文献   
56.
赵卫东 《山东医药》2004,44(14):11-12
目的 探讨在十二指肠乳头括约肌切开 (EST)胆总管取石术前静注咪唑安定的可行性及价值。方法 将 71例拟行 EST胆总管取石患者随机分为咪唑安定组 (试验组 ) 5 1例和对照组 (2 0例 ) ,两组术前均给予 6 5 4 -2 (10 mg)静脉注射 ,试验组同时静脉注射咪唑安定 (3~ 5 mg)。观察两组患者的进镜时间、麻醉程度 ,患者的反应与配合程度、自身感受程度 ,同时监测患者的血压、心率、血氧饱和度。结果 试验组进镜时间缩短、镇静程度适中、患者自身感受好 ,与对照组比较 ,差异有显著性 (P<0 .0 1) ;患者心血管及呼吸参数无明显变化。结论 EST胆总管取石术前静脉注射咪唑安定可提高麻醉效果 ,有利于提高患者配合的依从性 ,对血压、心率、血氧饱和度无明显影响  相似文献   
57.
Total extrusion of the talus without recovery of the bone is a very unusual injury. The authors present a case of a 25-year-old man who sustained an open total enucleation of the talus in a motorcycle accident. The talus was not recovered at the scene of the accident. An immediate tibiocalcaneal stabilization was performed by using an external fixator. In the postoperative period, a polymicrobic infection was observed and treated with parenteral antibiotics. Nine months after injury, the patient developed an infection of both the empty space and the distal third of the tibia. A wound debridement with tibial sequestrectomy and insertion of gentamicin-impregnated polymethylmethacrylate beads was performed. Three months later, after multiple negative bacteriologic examinations, a tibiocalcaneal arthrodesis with staples and autogenous bone graft was performed. Because of a pseudoarthrosis, the patient underwent a revision of the arthrodesis by retrograde tibiocalcaneal nailing, achieving clinical and radiographic success. The definitive treatment of total enucleation of the talus is still controversial because of its rarity and the high rate of complications, such as avascular necrosis, osteomyelitis, and ankle stiffness. In this case, without recovery of the talus, retrograde nailing afforded good stability by bypassing the bone defects.  相似文献   
58.
BACKGROUND: Severe ulcerative colitis is potentially life threatening even though a policy of intensive medical management and early colectomy in recent years reduced mortality to almost zero. However, colectomy, with or without ileal-anal anastomosis, has its own problems (morbidity, pouchitis, cuffitis) and no reliable prognostic index of surgical outcome has been developed. Intravenous steroids are still the mainstay of medical therapy but their maximal duration before stating a 'treatment failure' has not been defined. AIM OF THE STUDY: To evaluate the effectiveness, safety and outcome of an intensive medical approach in a series of patients with severe ulcerative colitis. PATIENTS AND METHODS: One hundred and forty-nine episodes of severe ulcerative colitis in 115 patients admitted to a Gastroenterology Unit in a 7-year period were retrospectively evaluated. Intravenous glucocorticosteroids--methylprednisolone 1 mg/kg/day--and topical steroids were administered, and supportive treatments with intensive monitoring were extended to all the patients. Second-line strategies for steroid-refractoriness were prolonged glucocorticosteroids treatment, oral ciclosporin, infliximab or surgery. RESULTS: The median number of Truelove criteria at admission was 3 (range 2-5), median CRP 34 mg/l (range 10-196). Median follow-up after discharge was 49 months. In 84 (57%) episodes an early response was noted, while 65 (43%) did not respond within 10 days to the standard steroid treatment. In the non-responders group, 28 patients went into remission with a prolonged steroid treatment (slow responders); 15 patients were treated with ciclosporin (eight responders) and 6 with infliximab (four responders). A total of 24 colectomies was performed in this group of patients (in 21 cases within 30 days from admission). Slow responders showed lower albumin levels (P = 0.02), higher cumulative dose of glucocorticosteroids in the year prior to admission (P = 0.02) and higher age (P = 0.03), in comparison with early responders. Major complications were noted in four episodes which responded to medical treatment. Disease-related mortality was zero. CONCLUSIONS: Medical treatment and use of second-line therapies were effective in the present series of patients. A group of slow responders has been identified and, if an intensive medical monitoring is guaranteed, steroids can be safely prolonged after the first 10 days of treatment. Cumulatively, about 80% of the patients responded to short-term medical treatment, only 5% of the patients underwent colectomy in the follow-up period. Major adverse events were recorded in four patients, who had recovered completely after adequate medical treatment.  相似文献   
59.
目的 了解套扎与硬化夹心联合法 (套扎 硬化 套扎 )能否获得优于单纯内镜下食管静脉曲张结扎 (EVL)的疗效。方法 对 98例肝硬化食管静脉曲张伴活动性出血或近期出血的患者随机采用单纯EVL或夹心法治疗 (EVL组 5 0例 ,夹心法组 4 8例 )。EVL组每条曲张静脉结扎皮圈不超过 3个 ,夹心法组每条曲张静脉结扎 2个皮圈 ,并在两个结扎点之间的曲张静脉内注射 1~ 3ml硬化剂。夹心法组 7例在首次内镜治疗时接受食管静脉造影检查。 7~ 10d重复 1次内镜治疗 ,直至静脉曲张消除。结果  7例行静脉造影检查 ,其中 6例硬化剂在曲张静脉内滞留时间超过 4 5min。两种方法控制活动性食管静脉曲张出血 (EVB)的止血成功率相同 (10 0 .0 % ) ;两组间静脉曲张消除率相似 (夹心法组 93.8% ,EVL组 90 .2 % ,P >0 .0 5 ) ,但夹心法组一次治疗后静脉曲张消除率明显高于EVL组 (6 6 .7%比10 .0 % ,P <0 .0 0 1) ,达到消除的平均治疗次数明显减少 (1.2± 0 .4比 3.8± 1.5 ,P <0 .0 1) ,所需时间显著缩短 [(13.1± 4 .3)d比 (42 .5± 16 .7)d ,P <0 .0 1];与EVL组相比 ,夹心法组再出血率较低 (8.3%比2 8.0 % ,P <0 .0 5 ) ,随访期内静脉曲张复发率明显下降 (8.3%比 4 4 .0 % ,P <0 .0 0 5 ) ;两组间并发症发生率相似 (夹心法组 1  相似文献   
60.
逆行静脉穿刺的临床应用效果观察   总被引:10,自引:1,他引:9  
目的探讨逆行静脉穿刺的临床应用效果,为长期静脉输液及浅静脉穿刺困难的患者提高手背浅静脉的利用率,以保护血管。方法随机选择静脉输液患者126例(正向和逆向静脉穿刺),采用掌指关节附近血管进行静脉穿刺。结果两种穿刺方法对同种液体最大滴速无显著影响(P〉0.05),对手的活动度及局部渗出、肿胀有显著影响(P〈0.01)。结论逆行静脉穿刺可提高穿刺的成功率,便于固定,增加患者的舒适度。  相似文献   
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