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171.
Modified sleeve anastomosis for reconstruction of the hepatic artery in rat liver transplantation 总被引:13,自引:0,他引:13
End-to-end sleeve anastomosis between a donor common hepatic artery and a recipient proper hepatic artery was proven to be the most physiological and simple method for hepatic rearterialization in rat liver transplantation. Current technical variants of the sleeve technique, however, are hampered by the high rate of bleeding from the anastomotic site. This report deals with a technical modification which inhibits postoperative bleeding efficiently. The procedure consisted of a guiding suture, as previously described in other technical variants, and a modified fixing suture. Instead of using a single stitch to fix the feeding vessel with the receiving vessel, a running suture between the edge of the donor common hepatic artery and the adventitia of the recipient proper hepatic artery was performed to avoid a possible backflow. The patency rate of 91% was as high as reported by others using a sleeve technique, which was also reflected in the histomorphological picture, being indistinguishable from normal liver histology. This technical modification simplified the procedure of reconstructing the hepatic artery and could contribute to a wider use of the arterialized liver transplantation model in rats. 相似文献
172.
A single subcutaneous bolus of erythropoietin normalizes cerebral blood flow autoregulation after subarachnoid haemorrhage in rats 总被引:10,自引:0,他引:10
Springborg JB Ma X Rochat P Knudsen GM Amtorp O Paulson OB Juhler M Olsen NV 《British journal of pharmacology》2002,135(3):823-829
Systemic administration of recombinant erythropoietin (EPO) has been demonstrated to mediate neuroprotection. This effect of EPO may in part rely on a beneficial effect on cerebrovascular dysfunction leading to ischaemic neuronal damage. We investigated the in vivo effects of subcutaneously administered recombinant EPO on impaired cerebral blood flow (CBF) autoregulation after experimental subarachnoid haemorrhage (SAH). Four groups of male Sprague-Dawley rats were studied: group A, sham operation plus vehicle; group B, sham operation plus EPO; group C, SAH plus vehicle; group D, SAH plus EPO. SAH was induced by injection of 0.07 ml of autologous blood into the cisterna magna. EPO (400 iu kg(-1) s.c.) or vehicle was given immediately after the subarachnoid injection of blood or saline. Forty-eight hours after the induction of SAH, CBF autoregulatory function was evaluated using the intracarotid (133)Xe method. CBF autoregulation was preserved in both sham-operated groups (lower limits of mean arterial blood pressure: 91+/-3 and 98+/-3 mmHg in groups A and B, respectively). In the vehicle treated SAH-group, autoregulation was abolished and the relationship between CBF and blood pressure was best described by a single linear regression line. A subcutaneous injection of EPO given immediately after the induction of SAH normalized autoregulation of CBF (lower limit in group D: 93+/-4 mmHg, NS compared with groups A and B). Early activation of endothelial EPO receptors may represent a potential therapeutic strategy in the treatment of cerebrovascular perturbations after SAH. 相似文献
173.
Maitland-van der Zee AH Stricker BH Klungel OH Kastelein JJ Hofman A Witteman JC Breteler MM Leufkens HG van Duijn CM de Boer A 《Pharmacogenetics》2002,12(8):647-653
We aimed to assess whether the effectiveness of statins in the prevention of myocardial infarction, stroke and total mortality is influenced by apolipoprotein E (apoE) genotype in an elderly population. We used data from the Rotterdam Study, a prospective population-based cohort study in the Netherlands which started in 1990 and included 7983 subjects aged 55 years and older. Subjects who were treated with cholesterol lowering drugs at baseline or with a serum total cholesterol > or = 6.5 mmol/l at baseline were included. We compared the incidence of myocardial infarction, stroke and total mortality in subjects who received > or = 2 years of statin treatment with that in subjects who had been treated for less than 2 years, and in untreated subjects, using a Cox proportional hazard model with cumulative statin use defined as time-dependent covariates. The adjusted relative risk of all-cause mortality was 0.79 [95% confidence interval (CI) 0.51-1.22] and of myocardial infarction and stroke 0.50 (95% CI 0.28-0.91) for subjects treated with statins for > or = 2 years compared to untreated subjects. The adjusted relative risks for subjects with the epsilon4 allele were 0.91 (95% CI 0.45-1.84) for all-cause mortality and 0.63 (95% CI 0.23-1.78) for myocardial infarction and stroke. In subjects without the epsilon4 allele, adjusted relative risks were 0.71 (95% CI 0.41-1.24) for all-cause mortality and 0.46 (95% CI 0.22-0.95) for myocardial infarction and stroke. We found a protective effect of statins on the risk of myocardial infarction and stroke that was independent of apoE genotype. The protective effect of statins on total mortality was not statistically significant, but did not seem to differ between subjects with different apoE genotypes. 相似文献
174.
Dietz U Horstick G Manke T Otto M Eick O Kirkpatrick CJ Meyer J Darius H 《Cardiology》2003,99(1):32-38
A previous study in rabbit hearts demonstrated the feasibility of creating transmyocardial channels by application of temperature-regulated high-frequency (HF) energy. Feasibility of creating non-transmural channels using a transvascular approach was tested in 14 pigs which were followed for 1 h, and 3 and 9 weeks (group A, B and C). Myocardial channels were found to be highly reproducible and patent in more than two thirds in group A. Channels were replaced by connective tissue during follow-up which contained newly formed small vessels. A functional communication between the left ventricular cavum and newly formed vessels of the channel remnants could be demonstrated in one heart of group C. Thus, intramyocardial HF ablation can be performed with high reproducibility to induce local angiogenesis. 相似文献
175.
Wöhrle J Grebe OC Nusser T Al-Khayer E Schaible S Kochs M Hombach V Höher M 《Circulation》2003,107(14):1840-1843
176.
EEG synchronization to modulated auditory tones in schizophrenia, schizoaffective disorder, and schizotypal personality disorder 总被引:5,自引:0,他引:5
Brenner CA Sporns O Lysaker PH O'Donnell BF 《The American journal of psychiatry》2003,160(12):2238-2240
OBJECTIVE: The authors tested whether neural synchronization deficits were present in subjects with schizophrenia and schizotypal personality disorder. METHOD: Amplitude-modulated tones were used to evaluate auditory steady-state evoked potential entrainment in a combined group of 21 subjects with schizophrenia or schizoaffective disorder, 11 subjects with schizotypal personality disorder, and 22 nonpsychiatric comparison subjects. RESULTS: The schizophrenia or schizoaffective disorder group exhibited decreased power compared to the schizotypal personality disorder and nonpsychiatric comparison groups. There were no differences between groups in N100 amplitude. CONCLUSIONS: Subjects with schizophrenia but not subjects with schizotypal personality disorder have deficits in steady-state responses to periodic stimuli, despite an intact response to sensory-evoked potentials (N100). These deficits reflect aberrant neural synchronization or resolution and may contribute to disturbed perceptual and cognitive integration in schizophrenia. 相似文献
177.
To test the hypothesis that characteristics of perinatal infection are associated with long-term cognitive limitations among preterm infants, we analyzed data from 294 infants (142 females, 152 males) < or = 1500 g birthweight and <37 completed weeks of gestation who were examined at age 9 years. We identified 47 children (20 females, 27 males) who had a non-verbal Kaufman Assessment Battery for Children (K-ABC) scale standard value below 70, i.e. more than 2 SDs below the age-adjusted mean. The 247 children (122 females, 125 males) with a score > or = 70 served as control participants. Maternal nationality and education, and low gestational age were significantly associated with a K-ABC non-verbal standard value <70. Both neonatal brain damage (intraventricular hemorrhage) and long-term sequelae (cerebral palsy [CP], diagnosed at age 6 years) were significantly associated with a below-normal non-verbal K-ABC score. Maternal fever at birth was present in five cases (11%) and eight controls (3%; odds ratio 3.6, 95% confidence interval 1.1 to 11.4). Clinical chorioamnionitis and preterm labor and/or premature rupture of membranes (as opposed to toxemia and other initiators of preterm delivery) were also more common among cases than control participants. When adjusting for potential confounders such as gestational age, maternal education and nationality, and CP, the risk estimate for maternal fever remained unchanged (3.8, 0.97 to 14.6). We conclude that perinatal infection might indeed contribute to an increased risk for long-term cognitive deficits in preterm infants. 相似文献
178.
Absolute quantification of proteins and phosphoproteins from cell lysates by tandem MS 总被引:20,自引:0,他引:20 下载免费PDF全文
Gerber SA Rush J Stemman O Kirschner MW Gygi SP 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(12):6940-6945
A need exists for technologies that permit the direct quantification of differences in protein and posttranslationally modified protein expression levels. Here we present a strategy for the absolute quantification (termed AQUA) of proteins and their modification states. Peptides are synthesized with incorporated stable isotopes as ideal internal standards to mimic native peptides formed by proteolysis. These synthetic peptides can also be prepared with covalent modifications (e.g., phosphorylation, methylation, acetylation, etc.) that are chemically identical to naturally occurring posttranslational modifications. Such AQUA internal standard peptides are then used to precisely and quantitatively measure the absolute levels of proteins and posttranslationally modified proteins after proteolysis by using a selected reaction monitoring analysis in a tandem mass spectrometer. In the present work, the AQUA strategy was used to (i) quantify low abundance yeast proteins involved in gene silencing, (ii) quantitatively determine the cell cycle-dependent phosphorylation of Ser-1126 of human separase protein, and (iii) identify kinases capable of phosphorylating Ser-1501 of separase in an in vitro kinase assay. The methods described here represent focused, alternative approaches for studying the dynamically changing proteome. 相似文献
179.
Müller O Traoré C Becher H Kouyaté B 《Tropical medicine & international health : TM & IH》2003,8(4):290-296
OBJECTIVE: To describe the pattern of fever-associated morbidity, treatment-seeking behaviour for fever episodes, and cause-specific mortality in young children of a malaria-holoendemic area in rural Burkina Faso. METHODS: In a longitudinal community-based intervention study, 709 representative children aged 6-31 months were followed daily over 6 months (including the main malaria transmission period) through village-based field staff. RESULTS: Of 1848 disease episodes, 1640 (89%) were fever episodes, and of those, 894 (55%) were attributed to malaria (fever + > or =5000 parasites/microl). Eighty-five percent of fever episodes were treated, mainly with chloroquine and paracetamol, 69% of treatments took place in households, 16% in local health centres, 13% in villages, and 1% in hospitals. Treatment-seeking in a health centre or hospital was associated with accessibility and disease severity. Cerebral malaria and malnutrition-associated diarrhoea were the most frequently diagnosed causes of death. While most children with a post-mortem diagnosis of diarrhoea had not received any treatment, children who died of malaria had often received insufficient treatment. In particular, there was a lack of an appropriate second-line treatment at formal health services after chloroquine treatment had failed to resolve symptoms. CONCLUSIONS: These findings call for more effective prevention and treatment of malaria, malnutrition and diarrhoea in rural African communities, as well as for better supervision of existing malaria treatment guidelines in formal health services. 相似文献
180.