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71.
A change in the polyacrylamide gel electrophoretic pattern of the double-stranded RNA genome segments of a cytoplasmic polyhedrosis virus was observed following only one or two passages through laboratory-reared larvae of Heliothis armigera. This change consisted of the loss of a high molecular weight segment concomitant with the appearance of a low molecular weight segment and was a reproducible feature observed with several separate isolates from the field. 相似文献
72.
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.
B Deslaugiers Ph Vaysse JM Combes J Guitard J Moscovici M Visentin D Vardon J Bécue 《Surgical and radiologic anatomy : SRA》1994,16(2):173-177
Summary The dissection of 100 external jugular veins in 50 cadavers was the object of this anatomic study. A certain number of notions concerning the afferent veins, the mode of termination and the valvular system of this vessel were defined. 1)Afferent veins. Along its pathway toward the deep venous system, the external jugular vein successively received: the transverse cervical vein in 88 cases (88%), usually opposite the intersection of the external jugular vein with the dorsal border of the sterno- cleidomastoid muscle; the suprascapular vein in 47 cases (47%); the anterior jugular vein in 46 cases (46%); the cervical vein or anastomosis with the latter in 13 cases (13%). 2)Mode of termination. Forty-three subjects presented a symmetric mechanism. 100 anastomoses can be classed into three types: in 60 cases (60%), the external jugular vein flowed into the jugulo-subclavian venous confluence; in 36 cases (36%), in to the subclavian vein at a distance from its junction with the internal jugular vein; in 4 cases (4%) in to the trunk of the internal jugular vein. 3)Study of the valves. There were studied in 25 subjects (50 external jugular veins). The valves were found in the ostial and paraostial position in 49 out of 50 veins.
Contribution à l'étude des afférences et de la terminaison de la veine jugulaire externe
Résumé Cette étude anatomique repose sur la dissection de 100 vv. jugulaires externes chez 50 cadavres. Elle a permis de préciser un certain nombre de notions concernant les veines afférentes, le mode de terminaison et le système valvulaire de ce vaisseau. 1)Veines afférentes. Le long de son trajet vers le sytème veineux profond, la v. jugulaire externe reçoit successivement: la v. cervicale transverse dans 88 cas (88 %), habituellement en regard du croisement de la v. jugulaire externe avec le bord dorsal du m. sterno-cléido-mastoïdien ; la v. supra-scapulaire dans 47 cas (47 %); la v. jugulaire antérieure dans 46 cas (46 %) ; la v. céphalique ou une anastomose avec celle-ci dans 13 cas (13 %). 2)Mode de terminaison. Quarante trois sujets présentent un dispositif symétrique. Les 100 abouchements peuvent être classés en trois types : dans 60 cas (60 %) la v. jugulaire externe se déverse dans le confluent veineux jugulo-subclavier ; dans 36 cas (36 %), dans la v. subclavière à distance de sa réunion avec la v. jugulaire interne ; dans 4 cas (4 %) dans le tronc de la v. jugulaire interne. 3)Etude des valvules. Recherchées chez 25 sujets (50 vv. jugulaires externes), les valvules ont été retrouvées dans 49 cas sur 50 en position ostiale ou paraostiale.相似文献
75.
This paper presents an evaluation of the inhalation and ingestion doses from exposure to Rn and Rn progeny; an overview of the human and animal health-effects data; estimations of the cancer risks from Rn and Rn-progeny exposures; and suggested limits for Rn concentrations in drinking water and indoor air. We suggest that a rounded Rn-in-water concentration limit of 10,000 pCi/l can be supported by health-effects considerations alone, based on the conservative "tolerance dose" concept and other conservative assumptions regarding lung dose. A practical concentration limit (or action level) of 20,000 pCi/l has been derived by estimations of exposure distributions in the United States and in relation to current U.S. Environmental Protection Agency (EPA) standards for U-tailings-contaminated buildings. Research needed for resolution of the uncertainties in these estimates is suggested. We conclude that before a maximum contaminant level (MCL) for Rn in water can be firmly established, the broader issue of setting the MCL for Rn in indoor air must be addressed. 相似文献
76.
Studies on the mechanism of phorbol ester-induced inhibition of intercellular junctional communication 总被引:1,自引:0,他引:1
Intercellular gap-junctional communication was measured using[14C]citrulline incorporation in co-cultures of argininosuccinatelyase-deficient human fibroblasts and argininosuccinate synthetase-deficientChinese Hamster V79 cells. As previously shown, in this systemjunctional communication is completely inhibited by the tumorpromoting phorbol ester 12-O-tetra-decanoylphorbol-13-acetate(TPA). In the absence of extracellular calcium, TPA inhibitionwas less pronounced. However, synergism with calcium ionophoreA23187 could not be demonstrated. Chlorpromazine, trifluoperazineand 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl esterpartially antagonised the effect of TPA. No antagonism was demonstrablebetween calmidazolium and TPA. Treatment of co-cultures withexogenous phospholipase C or 1-oleoyl-2-acetylglycerol (OAG)resulted in communication inhibition, suggesting that proteinkinase C activation is involved in the mechanism of phorbolester-mediated communication inhibition. However co-cultureswhich had been made refractory to TPA by prolonged exposureto high concentrations remained sensitive to inhibition by phospholipaseC and OAG. These results suggest either that diacylglycerolcan produce other effects independent of protein kinase C activation,or that refractoriness to phorbol esters is not simply due toa decrease in the amount of protein kinase C. 相似文献
77.
Attitudes toward aging were assessed in three groups of elderly men (age 65-85), including: hospitalized veterans, veteran outpatients, and a group of non-hospitalized "healthy" veteran volunteers, using the Rosencranz and McNevin Semantic Differential Scale. Social objects rated included an "old man", a "young man", and the participant, himself, ("self"). Attitudes toward "old men" were significantly more negative than attitudes toward "young men" in all three groups. In addition, significant group by "object-rated" interactions were obtained on the autonomous/dependent and instrumental/ineffective dimensions of this scale. These interactions were attributable to a more negative "self" rating by the hospitalized group. These results suggest that within the population studied, older persons in poor health tend to view themselves more like the stereotyped "old person" than do healthy old people, who tend to perceive themselves as being more like a "young person". 相似文献
78.
The ileoanal J pouch: radiographic evaluation 总被引:1,自引:0,他引:1
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through. 相似文献
79.
Michel Ribeiro Fernandes Caroline Lorenzoni Almeida Ghezzi Tomaz JM Grezzana-Filho Fl via Heinz Feier Ian Leipnitz Aljamir Duarte Chedid Carlos Thadeu Schmidt Cerski Marcio Fernandes Chedid Cl ber Rosito Pinto Kruel 《World journal of gastrointestinal surgery》2021,13(3):315-322
BACKGROUNDPrimary extra-gastrointestinal stromal tumors (E-GIST) of the liver are rare. The clinical presentation may range from asymptomatic to bleeding or manifestations of mass effect. Oncologic surgery followed by adjuvant therapy with imatinib is the standard of care. However, under specific circumstances, a cytoreductive approach may represent a therapeutic option. We describe herein the case of an 84-year-old woman who presented with a tender, protruding epigastric mass. Abdominal computed tomography scan revealed a large, heterogeneous mass located across segments III, IV, V, and VIII of the liver. The initial approach was transarterial embolization of the tumor, which elicited no appreciable response. Considering the large size and central location of the tumor and the advanced age of the patient, non-anatomic complete resection was indicated. Due to substantial intraoperative bleeding and hemodynamic instability, only a near-complete resection could be achieved. Histopathology and immunohistochemical staining confirmed the diagnosis of primary E-GIST of the liver. Considering the risk/benefit ratio for therapeutic options, debulking surgery may represent a strategy to control pain and prolong survival.CASE SUMMARYHere, we present a case report of a patient diagnosed with E-GIST primary of the liver, which was indicated a cytoreductive surgery and adjuvant therapy with imatinib.CONCLUSIONE-GIST primary of the liver is a rare conditional, the treatment is with systemic therapy and total resection surgery. However, a cytoreductive surgery will be necessary when a complete resection is no possible. 相似文献
80.
V. R. Harley D. Chan J. G. Rogers W. G. Cole 《Journal of inherited metabolic disease》1990,13(2):219-226
Summary The structure and metabolism of type I and III collagens were studied in fibroblast cultures and dermis from 25 unrelated patients including 23 with typical Marfan syndrome and two infants with a very severe clinical form of this syndrome. Electrophoretic analysis of collagen -chains, as well as one- and two-dimensional electrophoresis of collagen cyanogen bromide peptides, failed to show any evidence of primary structure defects or overmodification of lysine residues in these collagens. The proportion of hydroxylated prolyl residues in isolated 1(I) chains was also normal. There was a minimal increase in the proportion of type III collagen produced by nine cultures. The findings in this study indicate that the underlying molecular defects in the patients studied are unlikely to involve the structure of the main fibrillar type I and III collagens. 相似文献