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71.
Summary Seventy-five livers with metastases were cut sagitally into 1 cm thick slices. A total number of 11,581 metastases sections was exactly mapped. There was an average of 154 metastases sections per liver. The average diameter of the metastases was 1 cm. 40% of the metastases reached to the hepatic surface, and 60% were invisible due to their deposition in the internal parenchyma. In 8% of the livers there were only superficial metastases (average 3.2 metastases), and in 12% were only deep metastases detected (average 2.6). The total number of superficial metastases increased with increasing diameter of the secondary tumors.An approximately homogeneous distribution of hepatic metastases within the liver parenchyma has been demonstrated. 相似文献
72.
TLR2和TLR4在原发性肝癌中的表达 总被引:1,自引:0,他引:1
目的:本研究通过检测原发性肝癌Toll样受体2(TLR2)和Toll样受体4(TLR4)的表达,分析其与临床病理生理因素的关系,探讨TLR2,TLR4在原发性肝癌疾病过程中的可能作用。方法:采用免疫组化法和实时荧光定量PCR分别在蛋白水平及mRNA水平检测原发性肝癌组织和配对癌旁组织TLR2、TLR4的表达。结果:原发性肝癌组织在蛋白水平和mRNA水平TLR2和TLR4的表达均明显低于癌旁组织(P<0.01)。但免疫组化结果显示不论是肝癌组织还是癌旁组织,TLR2和TLR4的表达均明显高于正常肝组织(P<0.01,P<0.05),有门静脉分支癌栓的患者癌组织TLR4的表达强度低于无门静脉分支癌栓的患者(P<0.05)。结论:肝癌组织TLR2和TLR4的表达与癌旁组织相比受到相对抑制,但高于正常肝组织,TLR2和TLR4信号途径可能参与了原发性肝癌的病理过程。 相似文献
73.
Anatomic bases for liver transplantation 总被引:1,自引:0,他引:1
Summary This study gathers the anatomic implications for a good liver transplantation. During hepatic removal a left hepatic a.exists in 20% of cases; a right hepatic artery originating from the superior mesenteric a. (SMA) can be the only arterial supply in 9% of cases; the whole lesser omentum has to be removed and the SMA from 6 cm to its origin. The SMA must be freed from the celiac ganglia and its ostium removed with the celiac trunk in an aortic patch cut on the anterior side in order to avoid the renal ostia. During total hepatectomy, dissection of the portal triad is often difficult because of portal hypertension dilating accessory portal veins (parabiliary arcade) and pedicular lymphatics. Nerve plexuses are thick in front of the hepatic artery or behind the portal triad. Transection of triangular ligaments leads to the retrohepatic inferior vena cava (IVC) that must be freed from its posterior tributaries (right suprarenal vein and inferior phrenic veins flowing either into the IVC or into the hepatic veins). One big problem during hepatic replacement is the biliary anastomosis which must be well irrigated. In the recipient, dissection up to the hilum preserves hepatic and pancreatico-duodenal pedicles. The biliary tract of the graft must be cut low, behind the pancreas, and several centimeters of the gastroduodenal artery must be preserved to save hepatic and gastroduodenal pedicles.
Bases anatomiques de la transplantation hépatique
Résumé Ce travail rassemble les notions anatomiques nécessaires au bon déroulement d'une transplantation hépatique. Le prélèvement du greffon doit enlever tout le petit omentum contenant une éventuelle a. hépatique gauche née de l'a. gastrique gauche (20%) et emporter l'a. mésentérique supérieure jusqu'à 6 cm de son origine pour ne pas oublier une a. hépatique droite née de cette dernière: son ostium est pris avec le tronc clique dans un patch aortique découpé sur la face antérieure. Lors de l'hépatectomie totale, la dissection du pédicule hépatique est rendue délicate par l'hypertension portale qui dilate les veines portes diets accessoires (arcade parabiliaire) et les lymphatiques pédiculaires. Les plexus nerveux sont riches devant l'artère hépatique et derrière le pédicule. La section des ligaments triangulaires droit et gauche amène à la veine cave inférieure (VCI) rétro-hépatique qu'il faut libérer de ses afférences postérieures (en particulier la veine surrénale principale droite toujours haut située et les veines phréniques inférieures qui s'abouchent soit dans la VCI soit dans les veines hépatiques du carrefour). Lors du remplacement, l'anastomose biliaire doit être vascularisée. Chez le receveur la dissection jusqu'au hile permet de conserver les pédicules. La voie biliaire du greffon doit être coupée bas derrière le pancréas et les premiers centimètres de l'artère gastro-duodénale conservés pour préserver les pédicules hépatique et pancréaticoduodénal.相似文献
74.
Behavioral and neurochemical effects induced by subchronic combined exposure to toluene at 40 ppm and noise at 80 dB-A in rats 总被引:1,自引:0,他引:1
We investigated whether exposure to noise, in addition to its well-known potentiating effect on toluene-induced ototoxicity, may also exacerbate behavioral disturbances and brain neurochemical alterations produced by subchronic exposure to low toluene concentration. To test this hypothesis, we evaluated whether subchronic combined exposure (16 weeks, 104 h per week) to noise at 80 dB-A and toluene at 40 ppm potentiates the recently reported neurotoxic effects of subchronic exposure to 40 ppm toluene. Locomotor and rearing activities, sensitization to narcosis induced by acute toluene at high concentration, and tyrosine and tryptophan hydroxylase activities in the caudate-putamen and hippocampus were investigated in both male and female rats. Our results confirm that subchronic exposure to 40 ppm toluene significantly decreases rearing activity and leads to a sensitization to toluene-induced narcosis, as evaluated by loss of righting reflex, but fails to demonstrate any adverse effect of noise, alone or in combination with toluene. Given that toluene has addictive properties, the lack of potentiating behavioral and neurochemical effect of noise is discussed with regards to a recent study that has shown that methamphetamine neurotoxicity is potentiated by exposure to loud noise. 相似文献
75.
Amadou Kane Edmond Ekué Creppy Angelika Roth Robert Röschenthaler Guy Dirheimer 《Archives of toxicology》1986,58(4):219-224
The distribution of a single low dose of [3H]ochratoxin A (OTA) in different tissues of male Wistar rats, after administration by intubation, was investigated after 5 h, 24 h and 48 h. This dose corresponds to concentrations encountered in naturally contaminated feed (4 ppm). The distribution of [3H]-label varied with the time elapsed after administration; at 5 h the highest specific label was found in the stomach contents and in decreasing order in: intestinal contents, lung, liver, kidney, heart, fat, intestine, testes, and the lowest in muscles, spleen and brain. With exception of brain, fat, stomach and lung, all tissues showed maximum levels at 24 h, after which time the label decreased steadily, whereas in fat it increased.After a 12-week feeding experiment, with doses of 288.8 g/kg corresponding to an intake of 4 ppm in feed each 48 h, the DNA in liver and kidneys was investigated for damage. By the alkaline elution method combined with micro-spectrofluorimetric determinations of DNA, evidence for DNA single-strand breaks was obtained. These findings support reports on the carcinogenic action of OTA. 相似文献
76.
《Journal of the American Medical Directors Association》2022,23(4):690-694
ObjectiveWith increasing age, there is greater need for right-sided colonic resections than its left-sided counterparts. Older age is associated with limited physical and functional status, which carries greater operative risk. Improvements in robotic surgery questions its role, especially in older adults, compared with laparoscopy. The objective is to investigate whether robotic right hemicolectomy (RRH) is as safe and effective as laparoscopic right hemicolectomy (LHR) in octogenarians (age >80 years).DesignRetrospective cross-sectional analysis.Settings and ParticipantsOctogenarians who underwent elective RRH and LRH by the Tweed Colorectal Group over 5 years.MethodsComplications within 30 days, age, gender, smoking status, immunocompromised status, presence of diabetes, American Society of Anesthesiologists (ASA) physical status score, preoperative Eastern Cooperative Oncology Group (ECOG) performance status, mFI-5 (modified frailty index), operative time, method of anastomosis, postoperative length of stay (LOS), need for rehabilitation, and short-term oncologic data using the TNM criteria were compared using univariate and multivariate analysis.ResultsSeventy-eight elective patients were included. LRH and RRH groups had similar median ages, gender distribution, and comorbidities. Across the entire cohort, 61.5% had no 30-day complications. RRH had nonsignificantly shorter operative time but significantly shorter LOS (5 vs 8 days) and fewer minor complications (24.5% vs 34.5%). Major complications and overall complications were not significantly different between the groups. Lower ASA and ECOG status were associated with lower complication rates across both groups. Oncologic resection outcomes were similar for both approaches.Conclusions and ImplicationsRRH does not confer an increased risk of complications compared to LRH in the octogenarians and may be a viable alternative in the field of minimally invasive surgery for older patients. Future research should focus on intracorporeal anastomoses, as it is a potential confounder leading to the shorter inpatient LOS shown in our robotic group. 相似文献
77.
78.
79.
Isabel M. A. Brüggenwirth Maureen J. M. Werner René Adam Wojciech G. Polak Vincent Karam Michael A. Heneghan Arianeb Mehrabi Jürgen L. Klempnauer Andreas Paul Darius F. Mirza Johann Pratschke Mauro Salizzoni Daniel Cherqui Michael Allison Olivier Soubrane Steven J. Staffa David Zurakowski Robert J. Porte Vincent E. de Meijer all the other contributing centers the European Liver Intestine Transplant Association 《Transplant international》2021,34(10):1928-1937
High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (P < 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT. 相似文献
80.
Jacopo Lanari Morten Hagness Alessandra Sartori Eugenia Rosso Enrico Gringeri Svein Dueland Umberto Cillo Pål-Dag Line 《Transplant international》2021,34(9):1722-1732
Liver transplantation (LT) for colorectal liver metastasis (CRLM) may provide excellent survival rates in patients with unresectable disease. High tumor load is a risk factor for recurrence and low overall survival (OS) after liver resection (LR). We tested the hypothesis that LT could offer better survival than LR in patients with high tumor load. LR performed at Padua University Hospital for CRLM was compared with LT for unresectable CRLM performed both at Oslo and Padua. High tumor load was defined as tumor burden score (TBS) ≥ 9, and inclusion criteria were as in the SECA-I transplant study. 184 patients were eligible: 128 LRs and 56 LTs. 5-year OS after LR and LT was 40.5% and 54.7% (P = 0.102). In the high TBS cohort, 5-year OS after LR and LT was 22.7% and 52.2% (P = 0.055). In patients with Oslo score ≤ 2 and TBS ≥ 9 (13 LR; 24 LT) the 5-year OS after LR and LT was 14.6% and 69.1% (P = 0.002). The corresponding disease-free survival (DFS) was 0% and 22.9% (P = 0.005). Selected CRLM patients with low Oslo score and high TBS could benefit from LT with survival outcomes that are far better than what is achieved by LR. 相似文献