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81.
将Wistar大鼠随机分成氧化胆固醇组(Och)、纯胆固醇组(Pch)和对照组,分别用氧化胆固醇混合物(250mg/kg bw/d)、纯胆固醇(250mg/kg bw/d)以及悬浮固醇用的明胶液体给大鼠灌胃,连续二天。于第二次灌胃后18小时,从大鼠尾静脉注射伊文思兰溶液,并于注射后2小时处死;取出主动脉用荧光显微分光光度术测定主动脉内膜的通透性。此外,另一部分动物在第二次灌胃后24小时处死,取出主动脉作扫描电镜的内膜观察。结果表明,Och大鼠主动脉内膜的通透性显著高于Pch组与对照组大鼠(P<0.01),而Pch组大鼠主动脉内膜的通透性和对照组无显著差异(P>0.05)。 相似文献
82.
The use of three different mesh materials in the treatment of abdominal wall defects 总被引:1,自引:1,他引:0
N. Deligiannidis I. Papavasiliou K. Sapalidis I. Kesisoglou S. Papavramidis O. Gamvros 《Hernia》2002,6(2):51-55
Abstract
Abstract. Various prosthetic materials have been proposed for the repair of abdominal wall defects. These materials offer tension-free
repair and significantly lower recurrence rate. Their respective properties are related to such complications as seroma, infection,
fistula formation, intestinal adhesions and removal. We compared the final outcome in treating abdominal wall defects in 56
patients with three different prosthetic materials: conventional polypropylene in a preperitoneal location, expanded polytetrafluoroethylene
mesh, and hydrophilic membrane coated polyester mesh in an intraperitoneal location. The hydrophilic coated polyester group
exhibited the lowest complication rate and the polypropylene group the highest.
Electronic Publication 相似文献
83.
Abdominal Stab Wounds in Children: an 18-Year Experience 总被引:1,自引:0,他引:1
Hayrettin ?ztürk Abdurrahman Onen Selcuk Ot?u Ali hsan Dokucu Yusuf Yamur Senol Gedik 《European Journal of Trauma》2002,28(2):85-89
Objective: Evaluation of the diagnosis, management, and the role of selective treatment in children with abdominal stab wounds.
Patients and Methods: 59 children (56 male and three female) were included in the study. The patients' median age was 11.8 years (range, 5–14 years).
Time between injury and admission was about 3 h. Laparotomy was performed in 44 patients (74%). Solid organ injury was detected
in 32 of these patients (73%) and could not be observed in twelve (27%). 15 patients (26%) were treated conservatively, and
only one (6.6%) underwent laparotomy during the follow-up. The stomach was the most frequently injured organ (ten patients),
followed by the intestines (nine patients). Types of surgical treatment were as follows: primary suture in 28 patients, resection-anastomosis
in three, and osteotomy in two.
Results: Some prognostic factors such as presence of abdominal organ evisceration and pneumoperitoneum were not significantly correlated
with intraabdominal organ injury, whereas some other risk factors such as acute abdomen on admission (p < 0.002) or abdominal
clinical and hemodynamic findings (p < 0.001) showed significant correlation with intraabdominal organ injury. The relative
risk (odds ratio) of developing an intraabdominal organ injury was > 2 for patients with signs of an acute abdomen on admission.
Postoperative complications were observed in five patients with organ injuries. None of our patients died.
Conclusions: Conservative treatment can be safely performed in most children with abdominal stab injuries. Signs of major internal hemorrhage
or generalized peritonitis are an absolute indication for emergency operation for abdominal stab wounds. Peritoneal penetrations,
free air on the abdominal X-ray, and omental or intestinal evisceration are poor indicators of significant organ injuries,
and patients presenting these signs shold be closely followed up for developing acute abdominal symptoms.
Received: November 2, 2001; revision accepted: February 15, 2002 相似文献
84.
Relationships between Activators and Inhibitors of Plasminogen, and the Progression of Small Abdominal Aortic Aneurysms 总被引:1,自引:0,他引:1
J. S. Lindholt B. Jrgensen G. -P. Shi E. W. Henneberg 《European journal of vascular and endovascular surgery》2003,25(6):546-551
OBJECTIVE: plasmin is a common activator of the known proteolytic systems involved in the aneurysmal degradation, and is reported to be associated with the expansion of abdominal aortic aneurysms (AAA). The aim of this study was to study the activating pathways of plasminogen as predictors of the progression of AAA. MATERIALS AND METHODS: one hundred and twelve of 122 male patients with a small AAA (def.: +3cm) were interviewed, examined, had blood samples taken at diagnosis, and scanned annually for 1-5 years (mean 3.5 years), and referred for surgery if the AAA exceeded 5cm in diameter.A random sample of 70 of the 112 cases had plasma levels of urokinase-like-plasminogen activator (uPA), tissue-type-plasminogen activator (tPA), plasminogen-activator-inhibitor-1 (PAI-1), macrophage inhibiting factor (MIF), tumour-growth-factor-beta1 (TGF-beta1), homocysteine, and serum levels of IgA-antibodies against Chlamydia pneumoniae (IgA-CP) and Cotinine (a nicotine metabolite) measured. Spearmans correlation analysis was used for statistics. RESULTS: the annual expansion rate correlated positively with tPA, IgA-CP and S-Cotinine; r =0.37 (p=0.002), 0.29 (p=0.006) and 0.24 (p=0.038), while PAI1, uPA, TGF-beta1, homocysteine, and MIF did not. S-Cotinine did also correlate positively with tPA, r=0.24 (p=0.049). CONCLUSION: the aortic matrix degradation in AAA may be partly caused by an activation of plasminogen by tPA, but apparently not by uPA, which usually dominates matrix degradation. Smoking seems to be a factor for this pathway, while the pathways of IgA-CP and MIF, a new marker of aneurysmal progression, seem different. The latter observations suggest that other proteolytic pathways are involved in the aortic wall degradation in AAA. 相似文献
85.
目的总结坏疽穿孔性阑尾炎阑锁阑尾切除术后发生腹腔残余脓肿(PAIAA)的原因及防治体会。方法对2003年-2006年7月共763例阑尾切除术,其中75例坏疽穿孔阑尾炎,术后5例发生腹腔残余脓肿的临床资料行回顾性分析。结果5例病例均治愈出院,3例经抗感染保守治疗脓肿逐渐吸收而愈,2例手术引流后治愈。结论坏疽穿孔阑尾炎术后易发生腹腔残余脓肿,术中术后的正确处理是可以减少阑尾术后腹腔残余脓肿的发生。 相似文献
86.
Use of amniotic grafts in the repair of gastroschisis 总被引:1,自引:0,他引:1
This article describes the use of amniotic grafts (AG) in the repair of large abdominal wall defects in newborns with gastroschisis. From 1988 to 1995, 22 newborns with gastroschisis underwent surgical repair. In 12 primary closure (PC) was performed; in 10 the abdominal wall defect was covered with an AG. A double layer of AG was used and the graft was additionally covered with a silastic silo in 8 cases. The overall mortality was 14%; 3 children died from necrotizing enterocolitis or sepsis after AG. However, the difference in mortality of newborns with PC versus AG was not statistically significant. Patient characteristics, the postoperative courses, nd the frequency of complications were similar after PC and AG. It is concluded that AG has no negative impact on the postoperative course and yields a low overall mortality. In our opinion there are several advantages in using the AG technique: it is an autoplastic material that is readily available without costs, reefing and removal is unnecessary, and there is a potentially low rate of adhesions. 相似文献
87.
M. Antonelli M. L. Moro R. R. D'Errico G. Conti M. Bufi A. Gasparetto 《Intensive care medicine》1996,22(8):735-741
Objective The aim of this study was to identify risk factors and to describe epidemiological patterns for early—(EOB) and late—onset bacteremias (LOB) after trauma.Design A prospective study conducted on 141 consecutive trauma patients.Setting A general intensive care unit (ICU) of a university hospital.Patients All multiple trauma patients admitted to our general intensive care unit (ICU) from December 1990 to May 1992 were prospectively enrolled in the study. The following information was collected for each patient and recorded in a computer database: demography, severity of trauma according to the Abbreviated Injury Scale (AIS), severtity of trauma according to the Glasgow Coma Scale (GCS), presence of pneumothorax, pulmonary contusion, rib fractures, hemothorax, and abdominal trauma, use of mechanical ventilation, and placement of central venous catheters. Bacteremias were defined as EOB when onset occurred within 96 h after trauma, and as LOB when appearing after 96 h from trauma.Results Thirty-seven patients developed bacteremia during their ICU stay (26%): 11 (29.7%) EOB and 26 (70.3%) LOB. Gram-positive cocci were isolated more frequently in EOB than in LOB (x
2=4.1,P=0.04). The risk of EOB was significantly increased by the presence of pulmonary contusion [relative risk (RR) 15.0; confidence interval (CI) 1.99-113.25], pneumonia before the onset of bacteremia (RR 3.56; CI 1.17-10.69), AIS score greater than 32 and an abdominal injury score greater than 9 (RR 3.11; CI 1.02-9.49), while intravascular catheters and mechanical ventilation did not represent risk factors for EOB. LOB had a very different pattern and their risk was significantly increased by exposure to intravascular catheters (RR 4.96; CI 1.23-19.94) and to mechanical ventilation lasting more than 7 days (RR 3.6; CI 1.6-8.1).Conclusions Scoring with the AIS of the abdominal and thoracic trauma at admission to the ICU appears a useful tool for identifying trauma patients at increased risk of EOB. A rigorous policy of catheter placement and maintenance as a means of reducing late bacteremias in trauma patients is essential. 相似文献
88.
Management of abdominal sepsis 总被引:2,自引:0,他引:2
D. Berger K. Buttenschoen 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1998,383(1):35-43
Introduction: Today the management of the different forms of peritonitis is generally standardised. The classification of primary and secondary
peritonitis is well accepted. From a pathophysiological point of view, postoperative and post-traumatic peritonitis should
be considered as independent entities. The bacteriological isolates from the inflamed peritoneal cavity do not correlate with
the clinical course, and the occurrence of enterococci and bacteroides may be slightly related to ongoing infectious complications.
Classification: Valuable scoring systems mainly rely on systemic signs of the septic disease and seem to better differentiate the prognosis
of the disease than more surgically oriented scores do. Although the scoring systems did not allow any clinical decision,
they should be used to help better compare patients treated in different institutions. The observation of the minor relevance
of bacteriology and the superiority of general sepsis scores agrees with the fact that pre-existing septic organ dysfunction
and pre-existing comorbidity are the main determinants of mortality. Treatment: Surgical therapy focuses on the control of the source of infection because it has been clearly shown that, without resolving
the source of infection, the prognosis remains poor. Adjuvant surgical measures aim at the further reduction of the bacterial
load in the peritoneal cavity. Planned relaparotomy, relaparotomy on demand, and continuous closed peritoneal lavage are used.
Results: Clinical results proved these methods to be equally effective although pathophysiological considerations favour closed peritoneal
lavage. Conclusion: Summarising the available data, we need a more sophisticated understanding of the pathophysiology of the peritonitis, and
well-designed clinical studies are necessary to define the optimal surgical treatment modalities.
Received: 27 November 1997 相似文献
89.
Yuta Ishizuka Yasushi Ishida Qing-Hua Jin Ayumi Shimokawa Mitsuhiko Saita Kazuo Kato Takato Kunitake Takamitsu Hanamori Yoshio Mitsuyama Hiroshi Kannan 《Brain research》1998,789(1):10
Nitric oxide (NO) has recently been shown to modulate the hypothalamic–pituitary–adrenal axis response to interleukin-1β (IL-1β). We measured levels of nitrite (NO2−) and nitrate (NO3−) in the hypothalamic paraventricular nucleus (PVN) region using an in vivo brain microdialysis technique in conscious rats. Intraperitoneally administered IL-1β produced a significant increase in both NO2− and NO3− levels in the PVN region. We also examined the possible involvement of the abdominal vagal afferent nerves in this effect. In abdominal-vagotomized rats, the increase was significantly attenuated compared to that in sham-operated rats. Our results suggest that the abdominal vagal afferent nerves are involved in intraperitoneally administered IL-1β-induced NO release in the PVN region. 相似文献
90.
Hyett Jon; Moscoso Gonzalo; Nicolaides Kypros 《Human reproduction (Oxford, England)》1995,10(11):3045-3048
Pathological examination of the heart and great vessels wasperformed in 61 specimens obtained after surgical terminationof pregnancy for psychosocial indications at 918 weeksof gestation. The aorta and pulmonary trunk were identifiedand external diameters were measured at the level of, and distalto the aortic valve and pulmonary valve, the level of the aorticisthmus and thoracic aorta, and the proximal and distal ductusarteriosus. All eight vessel diameters increased linearly withgestational age and the ratio of the diameter of the aorticisthmus to that of the aortic valve or the distal ductus arteriosusalso increased with gestation. Early pregnancy is characterizedby rapid growth of the fetal head and this may well be the consequenceof a preferential distribution of left ventricular output infavour of the head due to relative narrowing of the aortic isthmusat this gestation. 相似文献