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OBJECTIVE: Enlargement of the ascending aorta is often combined with valvular, coronary, or other cardiac diseases. Reduction aortoplasty can be an optional therapy; however, indications regarding the diameter of aorta, the history of dilatation (poststenosis, bicuspid aortic valve), or the intraoperative management (wall excision, reduction suture, external reinforcement) are not established. METHODS: In a retrospective study between 1997 and 2005, we investigated 531 patients operated for aneurysm or ectasia of the ascending aorta (diameter: 45-76mm). Of these, in 50 patients, size-reducing ascending aortoplasty was performed. External reinforcement with a non-coated dacron prosthesis was added in order to stabilize the aortic wall. RESULTS: Aortoplasty was associated with aortic valve replacement in 47 cases (35 mechanical vs 12 biological), subvalvular myectomy in 29 cases, and CABG in 13 cases. The procedure was performed with low hospital mortality (2%) and a low postoperative morbidity. Computertomographic and echocardiographic diameters were significantly smaller after reduction (55.8+/-9mm down to 40.51+/-6.2mm (CT), p<0.002; 54.1+/-6.7mm preoperatively down to 38.7+/-7.1mm (echocardiography), p<0.002), with stable performance in long-term follow-up (mean follow-up time: 70 months). CONCLUSIONS: As demonstrated in this study, size reduction of the ascending aorta using aortoplasty with external reinforcement is a safe procedure with excellent long-term results. It is a therapeutic option in modern aortic surgery in patients with poststenotic dilatation of the aorta without impairment of the sinotubular junction of the aortic valve and root.  相似文献   
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The volume of the nuclei and nucleoli of certain hypothalamic centers (SON, PVN, SCN, AN, VMN) was determined in control rats and in rats after deafferentation of the mediobasal hypothalamus. Sex differences were found in the parvocellular formations of the control animals: The volumes of nuclei and nucleoli of neurons of AN and VMN, and also of the nucleolus of SCN neurons were larger in females than in males. After deafferentation of the mediobasal hypothalamus the volume of the cell nuclei was increased, especially in hypothalamic formations located outside the isolated zone. This increase was more clearly defined in rats constantly in a state of estrus after the operation. Statistically significant differences between volumes of both nuclei and nucleoli of the cells in subgroups of rats with permanent estrus and with permanent diestrus were found only in the case of SCN. No such differences were found for AN, despite the considerable difference in the constant of luteinizing hormone in the pituitary of the same rats. It is suggested that gonadotropin releasing factors are not produced by the cells of AN and that control over the succession of phases of the sex cycle may be exerted by SCN.Laboratory of Neuroendocrinology, I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Chernigovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 3, pp. 352–354, March, 1980.  相似文献   
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In the past several decades, marine organisms have generouslygifted to the pharmaceutical industries numerous naturallybioactive compounds with antiviral, antibacterial,antimalarial, anti-inflammatory, antioxidant, and anticancerpotentials. But till date only few anticancer drugs (cytarabine,vidarabine) have been commercially developed from marinecompounds while several others are currently in differentclinical trials. Majority of these compounds were tested in thetumor xenograft models, however, lack of anticancer potentialdata in the chemical- and/or oncogene-induced pre-initiationanimal carcinogenesis models might have cost some of the marineanticancer compounds an early exit from the clinical trials. Thisreview critically discusses importance of preclinicalevaluation, failure of human clinical trials with certainpotential anticancer agents, the screening tests used, and choiceof biomarkers.  相似文献   
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To learn the reasons for the high incidence of biliary carcinomain patients with anomalous arrangement of the pancreaticobiliaryduct (APBD) mutagenicity of the bile of APBD-modeled dogs thathad received a dorsal pancreatico-cholecystostomy was assayedby the Ames Salmonella mutation test. The bile from two outof 18 APBD dogs was mutagenic for Salmonella typhimurium strainTA98 under the condition of metabolic activation by rat liverS9 fraction, while the bile from 17 normal dogs was not mutagenic.Furthermore, the bile from five APBD dogs i.p. administered1-nitropyrene (1-NP), which is a typical environmental mutagen,was more mutagenic for strain TA98 than that from 1-NP-treatednormal dogs. The bile from the APBD dogs had very high amylaseactivity, indicating that the bile contained pancreatic juiceas a result of the pancreatico-cholecystostomy. When pancreaticjuice from a normal dog was added to the bile from 1-NP-treatednormal dogs, mutagenicity of the bile increased 1.6- to 2.0-fold.Furthermore, sulfatase increased the mutagenic activity of thebile in the presence of the pancreatic juice. HPLC revealedthat the bile from a 1-NP-treated APBD dog contained mutagenic1-nitro-6/8-hydroxypyrene and 1-nitro-3-hydroxypyrene, whilebile from a 1-NP-treated normal dog did not contain these deconjugatedproducts. The pancreatic juice from a normal dog had very high-glutamyltransferase (GGT) and aminopeptidase activities andlow sulfatase activity, but it had no ß-glucuronidaseactivity. In addition, the bacteria that easily infect the biliaryduct of APBD dogs, Escherichia coli, Klebsiella, Enterobacterand Proteus, had high ß-glucuronidase activity. Inparticular, Klebsiella showed a very high sulfatase activity.These results suggest that pancreatic juice enzymes and bacteriainfecting the biliary duct deconjugate the detoxified mutagensin the bile and induce mutagenicity of the bile from APBD dogsor APBD patients.  相似文献   
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Left atrial thrombus after acute pancreatitis (AP) is a rare clinical statement. Because of induction of systemic prothrombotic process by AP; some patients with underlying risk factors may develop an intra-cardiac thrombus. We present a 53 years-old-woman with moderate mitral stenosis and atrial fibrillation. However the patient was under warfarin treatment, she developed a big left atrial big thrombus which was originated from left atrial appendage after she was suffered from AP.  相似文献   
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Simple bone cyst (SBC) also known as unicameral bone cyst is a benign, radiolucent bone lesion that is seen commonly in childhood. These lesions are usually found incidentally although pain and swelling can be seen. The most common complication is a pathological fracture, and this is often the cause of presentation. Here, we present a 22-year-old male with right lower quadrant pain due to SBC related pathological fracture of right iliac bone which is mimicking acute appendicitis.  相似文献   
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