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71.
Background: Peptic ulcers are a frequent cause of upper G.I. bleeding. Since endoscopic methods may be unsuccessful, we have studied the feasibility of a new laparoscopic approach on a porcine model to control the bleeding of these ulcers with transgastric suturing. Methods: After approval of the Animal Ethics Committee, 20 pigs (20 kg) were anticoagulated with intravenous sodium heparin (400 U/kg), and anesthetized. A nasogastric tube was inserted and a 15 mmHg pneumoperitoneum was created. Two 10-mm trocars and one 5-mm trocar were inserted through the abdominal cavity for laparoscopic guidance of three 7-mm endoluminal trocars inside the stomach through the anterior wall. Two posterior gastric ulcers were mechanically made on each pig by a lift and cut technique. Ulcers were observed for at least 1 min for evidence of continued bleeding. First, bleeding ulcers were treated with sclerosing agents (epinephrine and ethanolmine oleate 5%); following sclerotherapy, ulcers were sutured intraluminaly with 2-0 silk, with intracorporeal knots. Results: Ulcers created extended into the vascular submucosa and averaged 7 mm in diameter. Bleeding rate was variable, but significant (2 cm3/min) in 40%. It was technically possible to suture these ulcers in 80%. Bleeding was controlled in 95% of cases with sclerotherapy and intraluminal sutures. One perforation of the posterior gastric wall occurred and four endoluminal trocars had to be reinserted after dislodgement. Conclusions: It is possible to technically control bleeding ulcers in most cases with a laparoscopic transgastric technique using sclerosing agent and intraluminal sutures. This approach is promising for future human application; also, the intragastric suturing skills developed may be useful for other surgical interventions.Poster presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Orlando, Florida, USA, 11–14 March 1995  相似文献   
72.
Summary Here ditary cerebral hemorrhage with amyloidosis Dutch type (HCHWA-D) is characterized clinically by recurrent strokes and pathologically by deposition of amyloid (A) in cerebral vessel walls and, to a lesser extent, in the neuropil. Distinct from Alzheimer's disease, amyloid formation in HCHWA-D is not associated with neurofibrillary changes. Since a central issue in the pathophysiology of Alzheimer's disease and related conditions is the role of A in the neurodegencrative process, we investigated HCHWA-D brains for the presence of neuritic abnormalities using antibodies to ubiquitin and to phosphorylated neurofilaments. The study showed that amyloid deposits in the vessel walls and in the neuropil were surrounded by abnormal ubiquitinated neurites, suggesting that A deposition induces neuritic changes.Supported by the Italian Ministry of Health. Department of Social Services, and by N.I.H. Grants AG05891 and AG08721 (to B.F.)  相似文献   
73.
Summary Blood (3.4–13.5% of blood volume) was pumped in and out of the circulation of rats at different rates and period lengths during continuous measurements of blood conductivity (reciprocally related to hematocrit) and arterial pressure. Hct followed the same zig-zag course as the induced changes of blood volume in every case, indicating that fluid shifts (v) between interstitium and intravascular space closely follow blood volume changes. As the het increase during reinfusion was not as great as the preceding decrease, hct dropped continuously during the 20–90 minutes of experimentation, so that a final volume increase (v) by about 4% was calculated, which was confirmed by a corresponding decrease of plasma protein concentration. Both final v and v during periodic volume change (% B.V.) were greater when arterial pressure dropped. v was directly related to % B.V. but not to its rate of change. Heart rate dropped slightly at the end of the reinfusion periods, whereas it rose to control at the end of the withdrawal periods. The results were regarded as evidence of blood volume regulation proportional to the absolute volume of blood lost in non-hypotensive hemorrhage.Supported by DFG-grant AZ 3/3  相似文献   
74.
Summary A nine-year-old boy, presenting only with signs of increased ICP, underwent computerized tomography. This examination demonstrated no abnormalities in the precontrast scan. Following C. E., it showed scattered areas of blood-like density in both hemispheres, as well as a presumedly abnormal vessel in the left occipital region and dilated vein of Galen, sinus rectus, and tentorial veins. The presumptive diagnosis of left occipital AVM was not confirmed by angiography, which also ruled out obstructions of the intracranial sinuses.The possible mechanism responsible for this atypical CT picture is briefly discussed in the light of pertinent literature. It is suggested that careful consideration should be given to the indications for angiography in similar cases, in the presence of a hypervascular aspect of the postcontrast CT scan, particularly if a considerable amount of contrast medium has been used.  相似文献   
75.
Children suffering from Gaucher's disease were examined by magnetic resonance imaging (MRI) during a characteristic episode of bone crisis. An unexpectedly high intramedullary as well as subperiosteal signal was observed on both the T1 and T2-weighted sequences in 5 patients, suggesting a subacute hemorrhage or hematoma. It is conceivable that such a painful hemorrhage is an important component of the bone crisis phenomenon. Furthermore, in these cases this is a specific sign which may enable differentiation of bone crises from other types of bone pain associated with Gaucher's disease.  相似文献   
76.
Methods for the acquisition and analysis of intracranial pressure (ICP) signals are reviewed from clinical and technical perspectives. The clinical importance of ICP monitoring is presented, and methods for ICP transduction are briefly discussed. These methods include intraventricular catheters, subarachnoid screws, epidural techniques, and the new fiberoptic ICP measurement systems. Approaches to the visual analysis of the ICP waveform are presented, with special emphasis on the relationship between the ICP waveform and the arterial blood pressure signal. Methods of computer-based ICP analysis are also reviewed, including histogram and systems analysis methods. Methods to predict ICP pressure rises and to estimate intracranial compliance are also discussed. Finally, ICP monitoring is reviewed from the point of view of patient outcome. It is concluded that advanced ICP waveform analysis methods warrant further clinical evaluation to demonstrate their clinical usefulness.  相似文献   
77.
Summary Contusions and lacerations of the frontal lobes are very frequent; 43.4% in the whole series of traumatic brain mass lesions. Clinical, ICP, CT scan data and neuropathological findings in patients with such lesions are analysed and correlated. Moreover, the clinical features and the outcome of frontal masses undergoing surgery are also compared with similar lesions located in the temporal lobes.Frontal lesions cannot be differentiated on purely clinical grounds and the factors governing the outcome in both locations are the same. On the whole, surgical indications nowadays seem to be rather rare; only lesions behaving truly as expanding lesions with obvious intracranial hypertension benefiting from surgery.Brain contusion-laceration syndromes in general can no longer be considered separate entities. Neither should they be included in the miscellaneous group of traumatic intracranial mass lesions, since the pathophysiological significance of purely extracerebral effusions is entirely different.Traumatic contusions and lacerations and/or intracerebral haematomas, whether frontal or located elsewhere, should, instead, be considered in the context of head injuries of a different degree of gravity, as having collateral features which, on occasion, may call for surgical management.  相似文献   
78.
目的实验研究重组组织纤溶酶原激活物预防蛛网膜下腔出血后迟发性脑血管痉挛(DVS).方法实验选取12只家犬,随机分成两组.采取"两次出血法"制成蛛网膜下腔出血(SAH)模型.SAH前先做基底动脉造影,然后行枕大池穿刺,抽出脑脊液4ml后注入等量自体动脉血.第一次"SAH"后48小时再次注入自体动脉血4ml.第二次注血后6小时治疗组6只动物经枕大池穿刺注入组织型纤维蛋白溶解酶原激活物(r-TPA)25mg;对照组注入生理盐水.7天后再次行基底动脉造影.结果动脉造影r-TPA治疗组基底动脉口径无明显变化(P>0.05);解剖除1例基底动脉外膜上可见数点凝血外,其余动物颅底均无血块.对照组两次动脉造影基底动脉缩小极为明显(P<0.01),有严重的血管痉挛.颅底充满血块,基底动脉被血块所包绕.结论r-TPA能充分地溶解未成熟的(SAH后48小时)蛛网膜下腔凝血块,从而有效的预防迟发性脑血管痉挛的出现.  相似文献   
79.
腰穿置管稳压引流治疗蛛网膜下腔出血后脑积水   总被引:1,自引:0,他引:1  
目的探讨蛛网膜下腔出血(SAH)后脑积水简便、安全、有效的治疗方法。方法所收治的283例SAH病人中有90例发生了急性脑积水,在内科治疗基础上,其中46例进行了腰穿置管稳压引流治疗结果与无脑积水者对照比较。结果上法治疗后32例(32/46,70%)意识水平均有所改善;所有受治病人12d内再出血和脑缺血的发生率与无脑积水的病人组无显著性差异〔5/46(11%),24/193(12%);16/46(35%)60/193(31%)。P>0.05〕。治疗组未发生脑室炎或脑膜炎。结论腰穿置管稳压引流是一种治疗SAH后脑积水简便、安全、有效的方法。  相似文献   
80.
产后出血的高危因素分析   总被引:14,自引:0,他引:14  
目的 分析产后出血发生的相关危险因素 ,探讨预防和减少产后出血的措施。方法 对我院1 990年 1月~ 2 0 0 2年 1 2月间住院分娩的产妇出现产后出血的产妇 31 9例 ,对照 6 38例。通过多元Logistic回归分析评价各危险因素的相对危险性。结果 产后出血的发病率为 2 0 9%。相对独立的多个危险因素作用大小的顺位为 :胎盘粘连或植入、前置胎盘、多胎妊娠及胎儿体重≥ 4 0 0 0g、重度妊高征、流产次数≥ 2次、胎盘早剥 ;在阴道分娩的产妇中 ,作用相对独立的危险因素的顺位为胎盘粘连或植入、胎儿体重≥ 4 0 0 0g、妊高征、第三产程 >1 0min、流产次数≥ 2次。结论 避免产前非意愿妊娠以减少前置胎盘、胎盘粘连或植入 ;减少巨大儿、多胎的发生 ,有助于预防和减少产后出血  相似文献   
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