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51.
应用微血管灌注透明法观察研究5具成人周围神经干标本.重点观察神经自然分束部位微血管形态和分支分布规律.神经干内有非常完兽的血供系统.手术中循神经自然分束进行追踪分离,不会对神经血供产生明显影响.但在张力下牵拉缝合神经,将对神经干血供产生严重影响.神经束膜缝合比神经外膜缝合更强调在无张力下进行. 相似文献
52.
53.
《Obesity research & clinical practice》2022,16(2):170-173
IntroductionSleeve gastrectomy has currently become the most commonly performed bariatric. procedure worldwide according to the last IFSO survey, overtaking gastric bypass with. a share of more than 50% of all primary bariatric-metabolic surgery. Gastric leak, intraluminal bleeding, bleeding from the staple-line and strictures are the most common complications. Portomesenteric vein thrombosis (PMVT)after sleeve gastrectomy is. another complication that has been increasingly reported in case-series in recent.years, although it remains uncommon. In this case report is described an extended portomesenteric vein thrombosis after. sleeve gastrectomy interesting splenic vein too with a favorable course and an. uneventful follow-up. We try to search in this case for pathogenetic factors involved in. this complication.Case reportA 42-year old man, with a body mass index (BMI) of 45 kg/m2, with a medical history of Obstructive Sleep Apnea Sindrome (OSAS) underwent laparoscopic sleeve gastrectomy. Early postoperative course was uneventful. Six days after discharge he complained abdominal pain and was admitted at the Emergency Department. A CT scan with intravenous contrast showed an occlusion of the portal vein, of the intrahepatic major branches and an extension to the superior mesenteric vein and the splenic vein. The patient received heparin and oral anticoagulation together with intravenous hydration and proton pump inhibitors. Considering the favourable course the patient was discharged after six days with long-term oral anticoagulation therapy. Anticoagulation with acenocumarol was continued for six months after a CT scan showed resolution of the PMVT without cavernoma. He had no recurrence of symptoms.DiscussionPorto-mesenteric thrombosis after sleeve gastrectomy is a rare complication but it has been increasingly reported over the last 10 years along with the extensive use of sleeve gastrectomy. Because PMVT is closely associated with sleeve gastrectomy in comparison with other bariatric procedures, we need to investigate what pathogenetic factors are involved in sleeve gastrectomy. Thrombophylic state, prolonged duration of surgery, high levels of pneumoperitoneum, thermal injury of the gastroepiploic vessels during greater curvature dissection, high intragastric pressure, inadequate antithrombotic prophylaxis and delayed mobilization of the patient after surgery have been reported as pathogenetic factors of portmesenteric vein thrombosis. Most of the cases presented in the literature such as our clinical case resolve with medical therapy, although portal vein thrombus extends into the superior mesenteric vein and the splenic vein.ConclusionPortomesenteric venous thrombosis is a rare but serious complication of bariatric surgery, especially associated with sleeve gastrectomy. Diagnosis is based on CT examination with intravenous contrast, and initial therapy is anticoagulation. Etiologic factors reported in the literature include a long duration of surgery, a high degree of pneumoperitoneum, high intragastric pressure after sleeve gastrectomy and thermal injury to the short gastric vessels and gastroepiploic arcade. Limited operative time, controlled values of pneumoperitoneum, careful dissection with energy device of gastric greater curvature, appropriate prophylaxis with low molecular weight heparin may be useful tools to prevent and limit this complication. Nonetheless we have to search which factors may condition the evolution of an extended PMVT as that described in this case towards resolution or to a further worsening clinical state. Early diagnosis? Correct treatment? Undiscovered patientrelated factors? 相似文献
54.
《Diagnostic Histopathology》2023,29(1):67-70
Non-alcoholic fatty liver disease (NAFLD), also referred to as metabolic associated fatty liver disease (MAFLD), is the commonest form of chronic liver disorder arising from metabolic dysregulation. It encompasses a wide spectrum of fatty liver phenotypes including isolated steatosis to non-alcoholic steatohepatitis (NASH). NASH is considered more likely to lead to grave clinical consequences such as cirrhosis and hepatocellular carcinoma, compared to simple steatosis. NASH is characterised by steatosis, inflammation, and damage to hepatocytes. Here, we present a case of a middle-aged gentleman with a background of infectious hepatitis who presented with NASH, with emphasis on terminology and histological assessment criteria of NAFLD and NASH. Reflection on and consistent effort to standardise terminology and assessment criteria will aid in addressing the scientific and clinical needs of NAFLD and NASH. 相似文献
55.
Tingting Ma Hao Zhang Tongxi Li Junjie Bai Ziming Wu Tianying Cai Yifan Chen Xianming Xia Yichao Du Wenguang Fu 《Phytotherapy research : PTR》2023,37(1):181-194
Hepatic ischemia–reperfusion injury (HIRI) is of common occurrence during liver surgery and transplantation. Pinocembrin (PIN) is a kind of flavonoid monomer extracted from the local traditional Chinese medicine Penthorum chinense Pursh (P. chinense). However, the effect of PIN on HIRI has not determined. We investigated the protective effect and potential mechanism of PIN against HIRI. Model mice were subjected to partial liver ischemia for 60 min, experimental mice were pretreated with PIN orally for 7 days, and H2O2-induced oxidative damage model in AML12 hepatic cells was established in vitro. Histopathologic analysis and serum biochemical levels revealed that PIN had hepatoprotective activities against HIRI. The variation of GSH, SOD, MDA, and ROS levels indicated that PIN treatments attenuated oxidative stress in tissue. PIN pretreatment obviously ameliorated apoptosis, and restrained the expression of HMGB1 and TLR4 in vivo. In vitro, compared with H2O2 group, the contents of ROS, mitochondrial membrane potential, apoptotic cells, and Bcl-2 protein were decreased, while the Bax protein expression was increased. Moreover, HMGB-1 small interfering RNA test and western blotting showed that PIN pretreatment reduced HMGB1 and TLR4 protein levels. In conclusion, PIN pretreatment effectively protected hepatocytes from HIRI and inhibited the HMGB1/TLR4 signaling pathway. 相似文献
56.
57.
Luis Cristovao Porto Michèle Chevallier Jean-Alexis Grimaud 《Virchows Archiv : an international journal of pathology》1989,414(4):299-307
Summary Alcohol induced perivenular fibrosis of terminal hepatic veins (THV) is claimed to be a precursor lesion leading to fibrosis development in man and baboon. The nature and significance of the THV lesions found in four baboons chronically fed with alcohol were studied in liver biopsies obtained during a three year period. The surface of THV wall and the number of mesenchymal cells were assessed with a semi-automatic image analyser. Histologically, THV were characterized as (a) phlebitic, in the presence of an inflammatory cell infiltrate involving the venous wall; (b) oedematous, when the connective tissue of the THV wall was disrupted or dissociated and (c) fibrotic, when perivenular scarring appeared as an increased rim. These lesions were present simultaneously and their intensity and distribution were independent of the duration of alcohol intoxication. Morphometric data obtained from these THV confirmed the thickening of the THV wall (WS/IS in: oedematous 1.05±0.36; phlebitic 1.65±1.04; fibrotic 1.47±0.36); and revealed an increased number of mesenchymal cells in fibrotic (439 m2/cell;p<0.01) and in phlebitic THV (510 m2/cell;p<0.05). A constant relationship was found between phlebitis and the presence of inflammatory infiltrate within the hepatic acini. Fibrotic THV was a less frequent finding and the lesion disappeared in the sequential biopsies of one of the baboons. In conclusion, THV lesions were heterogeneous and the collagen deposition in the THV wall was potentially reversible during the three year alcohol intoxication period, regardless the inflammatory reaction and, thus, did not indicate early irreversible hapatic fibrosis.Dr. Porto was supported by a fellowship from MEC-CAPES, Brazil. A grant for morphometric equipment was obtained from the Fondation pour la Recherche Médicale and from the Societé d'Hépatologie Expérimentale, 77 rue Pasteur, Lyon, France 相似文献
58.
Andrew D. Medhurst Gerd E. K. Novotny Stephen G. Parker Nicola M. Deighton Alberto J. Kaumann 《Naunyn-Schmiedeberg's archives of pharmacology》1993,347(3):257-265
Summary To investigate whether 5-HT1-like receptor-mediated inhibition of adenosine 3 : 5-cyclic monophosphate (cyclic AMP) accumulation occurs in nerves or smooth muscle of saphenous vein, infusions of 6-hydroxydopamine (6-OHDA) were administered to dogs with the aim of inducing sympathetic nerve damage. The effects of 6-OHDA on other 5-HT1-like receptor-mediated responses at the pre- and post-junctional level were investigated for comparison by studying 5-hydroxytryptamine (5-HT)-induced inhibition of 3H-noradrenaline release and contraction of smooth muscle respectively.Disruption of nerve function by 6-OHDA was revealed by the lack of catecholaminergic fluorescence and neurogenic contractile responses in saphenous veins from dogs treated with 6-OHDA. In addition, severe impairment of neuronal uptake mechanisms were apparent since basal efflux of 3H-noradrenaline, electrically-evoked release of 3H-noradrenaline and remaining 3H-noradrenaline content were considerably reduced. Some 3H-noradrenaline was taken up and released in 6-OHDA treated tissues which is consistent with the existence of nerve varicosities resistant to the present dosing regime of 6-OHDA, an observation substantiated by electron microscopy studies showing inconsistent lesions of nerve terminals.6-OHDA pre-treatment potentiated the smooth muscle contractile responses mediated by 5-HT1-like receptors as well as potentiating 5-HT-evoked inhibition of prostaglandin E2-stimulated cyclic AMP accumulation. It did not, however, affect 5-HT-induced inhibition of 3H-noradrenaline release. The present results suggest that inhibition of cyclic AMP accumulation by 5-HT occurs predominantly in smooth muscle.
Correspondence to A. J. Kaumann at the above address 相似文献
59.
目的 分析临床急性感染性疾病所致肝功能损害的特点及其恢复时间。方法 对 135例急性感染性疾病患者入院肝功能指标进行分析 ,观察治疗第 2周及第 4周时患者异常肝功能指标恢复情况。结果 除 6例死亡外 ,其余患者异常肝功能指标升高多在正常值上限 3倍以内 ,治疗第 4周异常肝功能指标治愈率分别为 AL T92 .4%、AST91.6 %、GGT75 .6 %、AL P91.3%、 SB10 0 %、 SB’ 10 0 %和 TBA 85 .7% ,HBs Ag ( )携带者与 HBs Ag (- )者治疗第 4周上述指标治愈率无显著差异。第 4周时 GGT仍升高者恢复缓慢或不易恢复正常。结论 急性感染性疾病致肝功能损害多呈轻度及一过性升高 ;HBs Ag ( )携带者肝脏应急储备及修复功能较正常人无明显下降 ;GGT恢复缓慢或不易恢复正常者可能留有持久性的肝内毛细胆管损伤 相似文献
60.
The experimental hepatic cirrhosis was induced either by bile duct ligation (BDL) or by pretreatment with dimethylnitrosamine
(DMNA). The pharmacokinetics of theophylline were studied after a single intravenous or a single oral administration. Using
the ultrafiltration method, protein-drug binding experiments were also carried out. The bilirubin level was several-fold increased
by BDL, but not by DMNA treatment. The albumin content was decreased in both cirrhotic groups. The total clearance (Clt, ml/kg/hr)
of theophylline in both hepatic cirrhosis groups significantly decreased and the terminal half-life (t1/2) in the cirrhotic rats was increased about two-fold after intravenous and oral administration. The volume of distribution
at steady state (Vdss, ml/kg) was increased slightly in the cirrhotic groups. Protein binding in BDL (8.67±4.85%) decreased
about four-folds, but in DMNA (73.00±9.85%) similar result, was observed as compared with the control. Increased free fraction
of theophylline did not increase the volume of distribution in BDL. Therefore decreased total body clearance of theophylline
was mainly due to decreased intrinsic clearance of theophylline in the liver. The absolute bioavailability of theophylline
in these experiments was between 63.8 and 72.8%(66.1% in BDL, 63.8% in Sham operated and Control, 72.8% in DMNA). These results
suggest that in the experimental hepatic cirrhosis model, administration route does not affect the disposition of theophylline. 相似文献