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61.
The possibility of poly(ADP-ribosyl)ation playing a role during liver regeneration induced by partial hepatectomy (PH) in vivo was examined. When rats were given an i.p. injection of 3-antinobenzamide (ABA) at a dose of 600 mg/kg body weight 12 h after PH, the levels of DNA synthesis at 20 h after PH were significantly reduced. The time course of DNA synthesis in regenerating liver was significantly delayed in the ABA-treated group. Enzymatic assay revealed the activity of poly-(ADP-ribose)polymerase (PADPRP) in controls to be increased in parallel with the increase of DNA synthesis induced by PH. This increase in PADPRP activity was delayed and very much weaker after ABA treatment. The results thus suggested that poly (AUP-ribosyl)ation might play an important role in DNA synthesis during liver regeneration in vivo.  相似文献   
62.
This study aimed to define the difference in cardiac hypertrophy between hypertensive patients with and without renal artery stenosis (RAS). When cardiac ultrasonographic examination was performed in 971 consecutive hypertensive outpatients, renal peak systolic velocity (PSV) was examined. Compared with patients without RAS, those with RAS (PSV ≥180 cm/s, 4.1%) were significantly older and included a higher proportion of male patients and had a higher left ventricular mass index (LVMI). A stratified analysis in the selected 120 patients showed that the LVMI was significantly higher in patients with RAS than in those without RAS for each confounding factor such as age and blood pressure. RAS was independently associated with a higher LVMI on propensity score analysis and multivariate analysis. Thus, the difference in LVMI between hypertensive patients with and without RAS was confirmed, irrespective of age and blood pressure, by stratified propensity score analysis and multivariate regression analysis.  相似文献   
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Hodgkin's lymphoma (HL) is in general a lymph node‐based disease. Hepatic involvement usually occurs in the advanced disease. Primary and prominent manifestation of the disease in the liver is extremely rare. We report magnetic resonance imaging leading to diagnosis in a rare case of liver involvement as the first sign of HL.  相似文献   
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We performed fixation using laminar screws in 2 patients in whom lateral mass screws, pedicle screws or transarticular screws could not be inserted. One was a 56-year-old woman who had anterior atlantoaxial subluxation (AAS). When a guide wire was inserted using an imaging guide, the hole bled massively. We thought the re-insertion of a guide wire or screw would thus increase the risk of vascular injury, so we used laminar screws. The other case was an 18-year-old man who had a hangman fracture. Preoperative magnetic resonance angiography showed occlusion of the left vertebral artery. A laminar screw was inserted into the patent side (i.e., the right side of C2). Cervical pedicle screws are the most biomechanically stable screws. However, their use carries a high risk of neurovascular complications during screw insertion, because the cervical pedicle is small and is adjacent laterally to the vertebral artery, medially to the spinal cord, and vertically to the nerve roots. Lateral mass screws are also reported to involve a risk of neurovascular injuries. The laminar screw method was thus thought to be useful, since arterial injuries could thus be avoided and it could also be used as a salvage modality for the previous misinsertion.  相似文献   
68.
A robust constrained blind source separation (CBSS) algorithm has been developed as an effective means to remove ocular artifacts (OAs) from electroencephalograms (EEGs). Currently, clinicians reject a data segment if the patient blinked or spoke during the observation interval. The rejected data segment could contain important information masked by the artifact. In the CBSS technique, a reference signal was exploited as a constraint. The constrained problem was then converted to an unconstrained problem by means of non-linear penalty functions weighted by the penalty terms. This led to the modification of the overall cost function, which was then minimised with the natural gradient algorithm. The effectiveness of the algorithm was also examined for the removal of other interfering signals such as electrocardiograms. The CBSS algorithm was tested with ten sets of data containing OAs. The proposed algorithm yielded, on average, a 19% performance improvement over Parra's BSS algorithm for removing OAs.  相似文献   
69.
To develop novel biodegradable biomedical materials, polylactide-grafted dextrans (Dex-g-PLA)s having various lengths, numbers of graft chains and sugar units were synthesized using the trimethylsilyl (TMS) protection method. To explore the possibility of using Dex-g-PLA as a biomedical soft-material, the contact angle, cell attachment and protein adsorption properties of the films prepared from these biodegradable and amphiphilic graft co-polymers were investigated. The poly-L-lactide (PLLA) film did not absorb water at all because of its high hydrophobicity, while the graft co-polymer films started immediately to swell after immersion in PBS. The percentage of water absorption at equilibrium increased with increasing sugar unit content. The receding contact angle of the Dex-g-PLA films against water was smaller than that of the PLLA film. The receding contact angle of Dex-g-PLA films against water decreased with increasing the sugar unit content. The top surface of the Dex-g-PLA film was suggested to be covered with hydrophilic Dex segments by means of annealing in water and to afford the wettable surface. Such a wettable surface led to the suppression of cell attachment and protein adsorption onto the film.  相似文献   
70.
To investigate the effects of polymorphisms in the ATP-binding cassette transporter A1 (ABCA1) gene on the high-density lipoprotein cholesterol (HDL-C) level and the incidence of myocardial infarction (MI), we performed association studies. Sequence analysis identified 14 polymorphisms in the promoter region of ABCA1. After considering linkage disequilibrium, three polymorphisms in the promoter region and 11 polymorphisms from the JSNP database were determined in 1,880 subjects recruited from the Suita Study, representing the general population in Japan. We evaluated the association between the ABCA1 genotype and HDL-C level adjusted not only for standard factors, but also for genetic factors including ApoA1 and ApoE genotypes. Of the 14 polymorphisms tested, the G(–273)C (P=0.0074), C(–297)T (P=0.0195), and IMS-JST071749 (P=0.0093) polymorphisms were significantly associated with the HDL-C level in the Suita population. We could reconfirm that the G(–273)C genotype was influential in another set of subjects (P=0.0310, n=743). However, the distribution of the ABCA1 G(–273)C genotype in subjects with MI (n=598) was not different from that in the control population (n=801). These results indicate that ABCA1 G(–273)C has a significant effect on the HDL-C level in the general Japanese population, but not on the incidence of MI.  相似文献   
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