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排序方式: 共有6016条查询结果,搜索用时 15 毫秒
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Stefano Di Domenico Giulio Bovio Maximiliano Gelli Ferruccio Ravazzoni Enzo Andorno Damiano Cottalasso Umberto Valente 《BMC surgery》2007,7(1):18
Background
Liver transplantation in presence of diffuse portal vein thrombosis is possible by using caval blood as portal inflow, through cavo-portal transposition. However, clinical results are heterogeneous and experimental studies are needed, but similar hemodynamic conditions are difficult to obtain, especially in small animals. Herein we describe a new simple model of cavo-portal transposition in rat. 相似文献3.
B Ricci 《Experimental eye research》1987,44(3):459-464
An experimental study was conducted on eight litters of newborn rats to evaluate the effects of supplemental oxygen administration on the retinal vasculature. The animals and their mothers were kept inside a pressure chamber and treated for the first 5 days of life. On the sixth day, they were removed and kept for five more days under room air and normobaric conditions. Three litters received continuous flow oxygen at 80% at a compression pressure of +81 kPa, one litter oxygen at 80% at a pressure of -39.5 kPa atms and three other litters received oxygen at 80% under normobaric conditions. The eighth litter was treated with room air oxygen at a compression pressure of +81 kPa. A severe retinopathy with marked retinal neovascularization was seen only in the newborn animals of the litters that received oxygen supplementation under normobaric or hypobaric conditions. Retinal vessels showed no pathological changes in the litters treated with hyperbaric normoxia or hyperoxia. It is possible to hypothesize that the prolonged period of oxygen supplementation failed to produce harmful effects on the retinal vasculature because the moderate hyperbarism caused mild retinal and choroidal vasoconstriction thus preventing excessive oxygen transport to the inner retina from the choroid during hyperoxia without inducing structural damage to the retinal tissue. 相似文献
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F. Ricci G. Castaldini G. de Manzoni G. Borzellino L. Rodella R. Kind 《Surgical endoscopy》1997,11(12):1179-1182
Background: Stones of the common bile duct are the most important factor in acute pancreatitis (AP). Endolaparoscopic surgery plays a well-recognized role in the treatment of this pathology. Methods: From January 1992 to December 1995 we observed 62 cases of acute biliary pancreatitis (ABP). In 57 cases (= 93.4%) we proposed a minimally invasive treatment, based on performance of endoscopic retrograde cholangiopancreatography (ERCP) combined with endoscopic sphincterotomy (ES) and then of laparoscopic cholecystectomy (LC). Results: ERCP was attempted in emergency in 40/57 cases and successfully done in 34 cases. An ES was performed in all but two cases. In 51 patients we performed LC. The overall morbidity was 8.9% with no mortality. Conclusions: In the case of ABP early treatment can achieve the restoration of patency of the papilla, reducing the risk of associated cholangitis and the development of pancreatic necrosis. The cholecystectomy prevents the risk of relapse of ABP. 相似文献
7.
A Rahmouni A Yang C M Tempany T Frenkel J Epstein P Walsh P K Leichner C Ricci E Zerhouni 《Journal of computer assisted tomography》1992,16(6):935-940
More accurate noninvasive estimation of prostate size is important in therapeutic trials for benign prostatic hyperplasia. The accuracy of MRI and transrectal ultrasound (TRUS) in assessing prostate weight was evaluated in 48 patients who underwent radical prostatectomy for stage A or B cancer. The volume derived from the wet weight of the freshly excised specimen was used as a reference. We compared that volume with volume estimates derived from the three-axis linear dimension measurement by MRI and TRUS using a tissue density of 1.05 g/cc and the standard formula for an ellipsoid object. Prostate and seminal vesicle volumes were also computed by contouring T2-weighted 5 mm thick contiguous MR images using a semiautomatic edge detection program and pixel summation. Three-axis volume MRI method versus volume from wet weight has slightly less scatter than TRUS three-axis method (r = 0.85 vs r = 0.81). Contoured MR volume method has the least scatter r = 0.93, statistically better than the linear axis method. Contoured MRI volumetric analysis appears superior to linear MRI or TRUS methods in estimating true prostate volume. 相似文献
8.
E A Cavalheiro M R de Feo O Mecarelli G Ricci 《Brain research. Developmental brain research》1992,67(2):371-374
Striatal pathways are important for modulating the threshold for seizures in the rat forebrain. N-Methyl-D-aspartate (NMDA), an excitatory amino acid derivative and powerful anticonvulsant agent, when injected into the brain, has been shown to protect adult rats against kindling and pilocarpine-induced seizures when injected into the caudate-putamen. The present study examines whether the anticonvulsant action of NMDA in the caudate-putamen varies with age. Bilateral striatal administration of NMDA was effective in suppressing bicuculline-induced seizures in rats older than 23 days of age. The results suggest that striatal pathways involved in the anticonvulsant activity of NMDA in the caudate-putamen are not functionally active in developing rats before the 4th week of life. 相似文献
9.
Claudio Baracchini Enzo Ballotta 《Journal of endovascular therapy》2004,11(6):749-50; author reply 750-1
10.
Annalisa Volpi Francesco Bacci Angelo Paradiso Luca Saragoni Emanuela Scarpi Monica Ricci Mirella Aldi Simonetta Bianchi Pietro Muretto Fiorella Nuzzo Gianni Simone Anita Mangia Francesco Schittulli Dino Amadori 《Modern pathology》2004,17(9):1038-1044
Available results highlight the lack of good level of evidence studies on the pure prognostic value of histological grade. In the present study, the prognostic relevance of histological grade and of its three components, tubule formation, nuclear pleomorphism and mitotic count, was analyzed in a series of 372 patients with node-negative breast cancer treated with locoregional therapy alone until early relapse. Histological grade was determined blindly by two observers and discordance between evaluations was resolved after joint review using a multihead microscope. No relation was observed between histological grade and any of its three components and disease-free survival. Conversely, a significant relation was observed between histological grade and distant metastasis-free survival (at 6 years, 94, 86 and 76% for grades 1, 2 and 3, respectively, P=0.013) as well as overall survival (98, 90 and 86%, P=0.001). A breakdown analysis as a function of the three components showed that neither tubule formation nor nuclear pleomorphism was associated with prognosis, and only mitotic count strongly influenced both distant metastasis-free survival (91, 82 and 74%, P=0.014) and overall survival (97, 87 and 85%, P=0.011). Histological grade suffers from a much higher subjectivity than any other microscopic evaluation of biomarkers as it is the sum of three different morphological features. Within the Italian Network for Quality Assessment of Tumor Biomarkers program we observed that histological grade is an independent prognostic variable, but also that this role is ascribable only to the number of mitotic figures. In conclusion, due to the ever smaller size of diagnosed breast cancers, resulting in less cancer tissue for biofunctional and molecular analysis, mitotic count evaluated under strict quality control conditions seems to be an accurate and feasible prognostic variable. 相似文献