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61.
Abstract Effects of copper and hydrocortisone on the proliferation of cultured fibroblasts from macular mouse, a model of Menkes kinky hair disease, were analyzed by flow cytometry. In fibroblasts from the macular mouse, copper induced cytotoxicity and S-phase accumulation of cell cycle were observed at lower concentrations of copper than in fibroblasts from the controls. However, the fibroblasts cultured with a combination of copper and hydrocortisone revealed recruitment of cell cycle. These results suggest that the proliferative activity of the cells from a macular mouse are more vulnerable to an excess amount of copper than normal, and that supplementation of hydrocortisone is effective for the Menkes kinky hair disease.  相似文献   
62.
We report here complications of percutaneous transhepatic catheterization of the portal venous system in 170 Japanese patients with portal hypertension. All patients underwent percutaneous transhepatic portography and percutaneous transhepatic obliteration of oesophagogastric varices was also performed in 29 patients. After retraction of the catheter, the puncture canal was plugged with gelatin sponge in 150 subjects and with one steel coil in 20 others. The overall complication rate was 16.5%. Intraperitoneal bleeding occurred in 10.6% of patients and 2.9% required blood transfusion. In these patients with intraperitoneal bleeding, the gelatin sponge was used for plugging after retraction of the catheter, while in the 20 patients with a steel coil plug, haemoperitoneum never occurred. Right pleural effusion was recognized in 3.5% of patients, intraperitoneal bile leakage in 1.8% and deterioration of liver function due to arteriovenous fistula in 0.6%. By univariate and multivariate analyses, female gender was the only risk factor for intraperitoneal bleeding among 150 patients investigated by percutaneous transhepatic catheterization of the portal venous system with gelatin sponge plugging. Intraperitoneal bleeding is the most important complication in patients with portal hypertension; it is difficult to predict intraperitoneal bleeding before retraction of the catheter in patients for whom gelatin sponge is used. Thus, for patients undergoing percutaneous transhepatic catheterization of the portal venous system, close follow up is recommended.  相似文献   
63.
Three patients with submassive hepatic necrosis developed acute liver failure during the severe reactivation of chronic hepatitis B. The activity of hepatitis B virus (HBV) DNA polymerase increased in all three patients immediately before the onset of hepatic failure. Liver biopsy specimens obtained before and after the episode of submassive hepatic necrosis showed progression to advanced liver cirrhosis. The nucleotide sequences of the precore and core regions of HBV-DNA were investigated in two of the three patients and in another two patients with piecemeal and bridging necrosis. The nucleotide and amino acid sequences of the HBV-DNA core region changed after reactivation in the the two patients with submassive hepatic necrosis, while the sequences in the other two patients with piecemeal necrosis remained unchanged before and after reactivation. These results suggest that the antigenicity of the HBV-DNA core region may have been changed before and after severe reactivation. Due to mutation at the core region, a different type of epitope would be expressed on the hepatocytes after submassive hepatic necrosis, which would not be a target for the cytotoxic T cell. This was evident by the continuation of the normal serum GPT for 5 and 9 years, respectively.  相似文献   
64.
Adrenocorticotropic hormone (ACTH)-releasing activity of synthetic carp Urotensin I (UI) and its ten synthetic fragments were examined using cultured rat pituitary cells. Both UI(1-41) and rat CRF (rCRF) increased ACTH release in a similar fashion at a concentration range from 10 pm to 100 nm. The potency of UI(1-41) was about one seventh that of rCRF on a molar basis. Four often UI fragments, UI(1-36), UI(4-36), UI(6-36) and UI(1-19) showed relatively strong ACTH-releasing activity, whereas both UI(9–36) and UI(17–36) showed extremely weak ACTH-releasing activity. However, all these fragments showed the activity in a dose-dependent manner parallel with that of UI(1-41). The activity of Ul(1-36) was weaker than Ul(1–41), suggesting that the C-terminal 37-41 sequence is required to express the full ACTH-release activity, although each of four C-terminal fragments, UI(24-36), UI(24-41), UI(29-36) and UI(29-41), exhibited no activity. In summary, the 4-19 amino acid sequence of UI(is important to exhibit ACTH-releasing activity and the C-terminal 37–41 sequence will be necessary to express the full activity.  相似文献   
65.
A male infant with distal 9q trisomy syndrome associated with an unusual inheritance of ABO blood type is reported. His clinical features were concordant with those of distal 9q trisomy syndrome. His karyotype was 46,XY, ?10, +der (10) t(9;10) (q22.3;q24.3) confirmed by G-banding and high resolution methods. His father had the balanced translocation t(9;10) (q22.3;924.3). He had a blood type of AB, despite his father's blood type of AB and his mother's blood type of O. The gene of ABO blood type is located at 9q34.1-q34.2. Therefore, he would have received A and B type alleles from his father. 9q trisomy syndrome should be carefully investigated with ABO blood type.  相似文献   
66.
Transposable elements are DNA sequences that can move or duplicativelytranspose on the chromosome. A simple model of transposableelements was studied, and the frequency spectrum, allelism,and identity coefficients at equilibrium were obtained. In theanalyses, the two cases of asexual haploid with no recombinationand diploid with free recombination were treated separately.It was shown that the multiple allele theory of population geneticsis applicable to the problems of frequency spectrum and allelism.On the other hand, identity coefficients may be formulated analogouslyto the treatment of concerted evolution of multigene families.Results indicate that, except for allelic identity, the modelof transposable elements and that of multigene families predictsimilar values of identity coefficients  相似文献   
67.
68.
Ruptured aneurysms of anterior inferior cerebellar artery (AICA) after radiotherapy for vestibular schwannoma (VS) are rare, and no definite treatment has been established for distal AICA pseudoaneurysms. We describe a 61-year-old man who underwent Gamma Knife surgery (GKS) for left VS. Follow-up magnetic resonance imaging (MRI) revealed partial regression of the tumor. Twelve years after GKS, he suffered from subarachnoid hemorrhage. Initial angiogram showed no vascular lesions; second left vertebral angiogram, 10 days after admission, demonstrated a pseudoaneurysm in the lateral pontine segment of the left AICA. The proximal portion of the AICA was occluded by a coil. Postoperative MRI revealed an infarction on the left side of the pons and brachium pontis. Although the patient suffered from mild postoperative cerebellar ataxia and facial and abducens nerve palsy, he was discharged 1 month postoperatively requiring no assistance with activities of daily living. Twelve months later, he recovered satisfactorily with a modified Rankin Scale grade of 1, and no recanalization of the aneurysm was found on MR angiography. Endovascular parent artery occlusion for ruptured aneurysms at distal AICA carries the risk of brain stem infarction, but should be considered when no other option is available such as after radiotherapy for VS.  相似文献   
69.
Using a new method devised by our laboratory, the ultrastructure of dermal glycosaminoglycan in an involved area of lichen myxoedematosus was examined. Although histochemical and biochemical studies have indicated simply an accumulated deposition of hyaluronic acid in the lesion, the glycosaminoglycan ultrastructure within it was distinaly different from that in normal skin. The glycosaminoglycan structure of normal skin was similar to the proteoglycan aggregate model described by Rosenberg (1975). As confirmed by the enzymatic digestion procedure, it represents the ultrastructure of hyaluronic acid bound to glycosaminoglycans such as dermatan sulphate or chondroitin sulphate. In contrast, hyaluronic acid filaments observed in lesions of lichen myxoedematosus contained no glycosaminoglycan subunits.  相似文献   
70.
Summary Resonance frequency analysis (RFA) was introduced as a method for measuring implant stability more than a decade ago. Implant stability quotient (ISQ) values obtained using a recently introduced wireless RFA device have made it possible to evaluate stability in a non‐invasive technique; however, there are few studies of the factors that affect ISQ values determined using this device. The aim of the present study was to evaluate the association between ISQ values determined by wireless RFA and various factors related to dental implant stability using a pig cortical bone model. Dental implants (Replace® Select Tapered implants) with a length of 10 mm were placed into pig cortical bone samples, then, ISQ values were determined using wireless RFA under various conditions (probe orientation, diameter of implant, insertion torque and peri‐implant bone loss). The results of this study showed that ISQ values were not affected by the direction of the probe from parallel to perpendicular to the long axis of the pig bone or to the smart peg. In addition, the diameter of the implant did not have a significant effect on the measured ISQ values. Statistically significant correlations were found between insertion torque and ISQ values (Spearman’s test, P < 0·05), and lower ISQ values were observed for deeper peri‐implant vertical defects (Mann–Whitney U‐test, P < 0·05). A wireless RFA device appears to be useful for measuring implant stability within the limits of the present in vitro study.  相似文献   
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