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31.
32.
In the present study we evaluated the protective activity of pyridoxol L,2-pyrrolidon-5 carboxylate (metadoxine) against CCl4 intoxication in rats, especially in relation to liver fibrosis. After 6 consecutive weeks of CCl4 treatment, the animals developed liver fibrosis and inflammation as revealed by histological analysis which also included semiquantitative scoring of these features. In addition the serum levels of the immunoreactive prolyl hydroxylase (SIRPH), an enzyme involved in the hydroxylation of the procollagen molecule, were significantly higher (44.2 +/- 16.3 micrograms/ml; P less than 0.005) in this group of animals than in controls (26.1 +/- 8.06). On the contrary, animals treated with CCl4 + metadoxine (200 mg/kg i.p.) had less severe liver fibrosis and normal SIRPH levels (21.5 +/- 14.6). These data suggest that metadoxine may be an effective pharmacological tool for preventing the progression of liver disease in rats exposed to CCl4 to cirrhosis. 相似文献
33.
Enrico Verrina Barbara Andreetta Sergio Bassi Roberto Bonaudo Domenica A. Caringella Alfonso Castellani Pierluigi Cavalli Alberto Edefonti Giancarlo Lavoratti Luigi Longo Ivana Pela Rosa Penza Francesco Perfumo Virgilio Petrucci Marina Picca Mauro Ragaiolo Stefano Rinaldi Gianfranco Rizzoni Palma Sorino Giusto Viglino Graziella Zacchello Rosanna Gusmano 《Pediatric nephrology (Berlin, Germany)》1992,6(1):78-81
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%. 相似文献
34.
Metabolic transformation of the mucoregulator and bronchodilator 7-(1,3-thiazolidin-2-ylmethyl)theophylline was studied in vitro with a rat liver microsomal preparation containing a NADPH-generating system. The only metabolite observed was 7-theophyllinacetaldehyde. In contrast to previous literature pointing out the chemical nature of 2-substituted thiazolidine ring cleavage, the formation of 7-theophyllinacetaldehyde was mediated by monooxygenase-dependent oxidation. Possibly an unstable sulfoxide was the first metabolic product, rapidly converted to 7-theophyllinacetaldehyde by hydrolysis. The sulfoxidation was apparently catalyzed mainly by flavin-containing monooxygenases, as selective thermal inactivation and methymazole significantly reduced the rate of formation of the metabolite. No N7-dealkylation pathway producing theophylline was detected, indicating a high regioselectivity in in vitro metabolism, due to the nucleophilicity of the sulfur atom. 相似文献
35.
beta/A4, a peptide that forms the extracellular amyloid fibrils of Alzheimer senile plaques, has also been proposed to be a component of Alzheimer paired helical filaments (PHFs). We compared BR88, an antiserum to amino acids 1-12 of beta/A4, with BR126, an antiserum to the sequence SEKLDFKDRVQS in tau protein, since tau protein is the only confirmed component of PHFs. In enzyme-linked immunosorbent assays (ELISAs), both antibodies reacted with pronase-treated PHFs better after PHFs were treated with guanidine. tau protein shares no sequence homology with beta/A4. Nevertheless, BR88 cross-reacted with human recombinant tau isoforms by ELISA and Western blot analysis with potencies comparable to those for anti-tau antibodies. BR88 reacted with a beta/A4 peptide as well on a molar basis as with tau protein and showed some reactivity to the tubulin-binding region of tau protein. In conclusion, the beta/A4 antiserum BR88 cross-reacts with tau protein, possibly explaining its reactivity with PHFs. 相似文献
36.
Ruggero de Paulis Fabrizio Tomai Fabio Bertoldo Anna S Ghini Raffaele Scaffa Paolo Nardi Luigi Chiariello 《European journal of cardio-thoracic surgery》2004,26(1):66-72
OBJECTIVES: The sinuses of Valsalva are known to contribute to the normal function of the aortic valve. Little is known about their role in promoting coronary artery blood flow. The aim of this study was to compare coronary artery flow characteristics among patients undergoing a Bentall operation by means of a conventional cylindrical Dacron conduit or with a new conduit with pseudosinuses of Valsalva or in patients retaining their natural sinuses of Valsalva after aortic valve and supracoronary ascending aorta replacement. METHODS: One year after a Bentall procedure with a standard cylindrical Dacron conduit (7 patients, group A) or with the new conduit (7 patients, group B), or after aortic valve and ascending aortic replacement (control group, 7 patients, group C) coronary flow velocity reserve and diastolic to systolic time integral ratio at baseline and after maximal hyperemia (with 40 microg of adenosine) were assessed by using a 0.014-in. Doppler guidewire positioned in the middle portion of the left anterior descending coronary artery. All patients were in NYHA class I, sinus rhythm and free of coronary disease. RESULTS: Arterial blood pressures and heart rate were comparable among groups. Intracoronary Doppler measurements did not show any significant difference in coronary vascular reserve between the three groups (3.6+/-0.4 vs 3.1+/-0.7 vs 3.7+/-0.5, P = 0.2). A greater diastolic component at baseline was present in group B patients (5.5+/-1.9 vs 3.5+/-0.9 in group A and 3.7+/-0.9 in group C, P = 0.024). After maximal hyperemia the diastolic component increased slightly in group A patients (8%) while both in groups B and C significantly decreased (-15 and -20%, respectively) (P = 0.017). CONCLUSIONS: The presence of pseudosinuses of Valsalva does not influence coronary flow reserve. After maximal coronary vasodilation the increase in the systolic component of coronary flow is more evident in the presence of sinuses or pseudosinuses of Valsalva, thus suggesting that coronary flow pattern may be affected by the presence of sinuses. 相似文献
37.
Giant cavernous hemangiomas: Diagnosis and surgical strategies 总被引:4,自引:0,他引:4
Prof. Mario Lise M.D. Gianpietro Feltrin M.D. Pier Paolo Da Pian M.D. Diego Miotto M.D. Pier Luigi Pilati M.D. Leopoldo Rubaltelli M.D. Donatella Zane M.D. 《World journal of surgery》1992,16(3):516-520
From January, 1972 to June, 1989, 51 patients with liver hemangiomas (32 females and 19 males, mean age 35 years) were evaluated for surgical treatment. Diameters of the masses were 5 cm to 20 cm (median 8.5 cm). Nine of the patients had already been treated for cancer. Twenty-two (43.1%) of the 51 patients were symptomatic and 29 (56.9%) patients were asymptomatic. In 34 patients (66.7%) a definite diagnosis of hemangioma was made by scintiscan and/or ultrasound and/or computed tomography and/or angiography while in the remaining 17 (33.3%) patients the diagnosis was uncertain. The most common indications for resection were the presence of a symptomatic angioma, a symptomatic mass with an uncertain diagnosis, and/or lack of a definite pre-operative diagnosis. Surgery was performed on 25 patients. Ten anatomic and 15 atypical resections or enucleations were performed. There were no postoperative deaths. Two further patients, operated for probable hemangioma, were found to have primary hepatic malignancies. In the 26 unresected patients, no complications were observed during follow-up. In 3 patients, hemangioma enlargement was detected by ultrasound, but there were no symptoms. As cavernous liver hemangiomas are now more reliably diagnosed and their natural history is usually uneventful, surgery can be avoided in most cases. However, when a non-resection policy is adopted, an exact diagnosis is essential in order to rule out primary or metastatic cancer. Surgical exploration and treatment should be limited to symptomatic or complicated cases as well as to patients with an uncertain diagnosis.
Resumen Cincuenta y un pacientes con hemangiomas del higado (32 mujeres y 19 hombres, edad promedio 35 años) fueron valorados en cuanto a tratamiento quirúrgico en el período enero 1972 a junio de 1989; el diámetro de las lesiones oscilo entre 5 y 20 cm (promedio 8.5 cm). Nueve de los pacientes ya habían sido tratados por cáncer; 22/51 (43.1%) estaban sintomáticos y 29/51 (56.9%) eran asintomáticos. En 34/51 (66.7%) se hizo el diagnóstico definitivo de hemangioma mediante escintigrafia y/o ultrasonido y/o tomografía computadorizada y/o angiografia, en tanto que en los otros 17 pacientes (33.3%) el diagnóstico resultó incierto. Las indicaciones más comunes para resección fueron: presencia de un angioma sintomático, una masa asintomática con diagnóstico incierto y/o ausencia de diagnóstico preoperatorio definitivo. Se practicó cirugía en 25/51 pacientes, habiéndose realizado 10 resecciones anatómicas y 15 resecciones atípicas o enucleaciones. No hubo muertes postoperatorias. Otros dos pacientes operados por probable hemangioma demostraron tener neoplasias malignas hepáticas primarias. En los 26 pacientes no resecados no se observaron complicaciones durante el seguimiento; en tres casos se detectó ensanche del hemangioma en el examen con ultrasonido, pero no se presentaron síntomas. Puesto que actualmente los hemangiomas cavernosos del hígado pueden ser diagnosticados con mayor certeza y puesto que su historia natural generalmente está libre de complicaciones es posible evitar la cirugía en la mayoría de los casos. Sin embargo, cuando se pretenda adoptar una política de no resección es esencial establecer el diagnóstico exacto para excluir la posibilidad de un cáncer primario o metastásico. La exploración y el tratamiento quirúrgicos debe permanecer limitados a los hemangiomas sintomáticos o complicados, y en ningún caso deben significar riesgo para el paciente.
Résumé De Janvier 1972 à Juin 1989, 51 patients ayant un hémangiome du foie (32 femmes et 19 hommes, âge moyen 35 ans) ont été examinés en vue d'une exérèse chirurgicale. Le diamètre de la lésion variait entre 5 et 20 cm (médiane = 8.5 cm). Neuf des patients avaient déjà été traités pour un cancer; 22/51 (43.1%) étaient symptomatiques alors que 29/51 (56.9%) étaient asymptomatiques. Chez 34/51 patients (66.7%), le diagnostic définitif d'hémangiome a été confirmé par scintigraphie et/ou échographie et/ou tomodensitométrie, alors que chez les 17 autres (33.3%), le diagnostic était uncertain. Les indications d'une résection les plus fréquentes étaient: la présence d'un angiome symptomatique, une masse symptomatique avec un diagnostic uncertain, et/ou absence de diagnostic définitif préopératoire. Vingt-cinq des 51 patients ont été opérés. Il y a eu 10 résections anatomiques et 15 résections atypiques ou énucléations. Il n'y a pas eu de mortalité postopératoire. Deux autres patients, traités pour ce que l'on soupçonnait être une probalbe hémangiome du foie, avaient en fait un cancer hépatique. Chez les 26 patients non résequés, il n'y avait pas eu de complication. Chez trois patients, on a mis en évidence une augmentation de volume par l'échographie, mais ces modifications ne s'accompagnait d'aucune symptomatologie. Comme on peut faire le diagnostic d'hémangiome carverneux du foie avec plus de fiabilité qu'avant, et comme on sait que leur histoire naturelle est généralement bénigne, on peut le plus souvent surseoir à l'exérèse chirurgicale. Cependant, il importe de toujours faire le diagnositc avec certitude, de façon à éliminer un cancer primitif ou sécondaire du foie.相似文献
38.
Mario Lapecorella Assunta Orecchioni Luigi Dell'Orso Guglielmo Mariani 《Blood coagulation & fibrinolysis》2007,18(5):513-517
The intake of steroid hormone contraceptives is a strong and independent risk factor for venous thromboembolism. Several studies have assessed an increased risk of venous thromboembolism in women using oral contraceptives who are carriers of the G20210A mutation in the prothrombin gene. Most trials evaluating the thrombotic risk of oral contraceptives are based on combined oral preparations, but only a few focus on progestogen-only oral preparations. Results from such studies are conflicting and globally assess the thrombotic risk, ranging from modest to slightly increased. Furthermore, little is known about the relationship between the C677T mutation in the methylenetetrahydrofolate reductase gene and the progestogen-based preparations. Herewith we report the case of a 49-year-old woman with a complex genetic thrombosis risk factor who had taken oral progesterone for 15 months without any complication, but then experienced severe left upper extremity deep vein thrombosis 2 months after the drug suspension. 相似文献
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40.