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1.
Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy.  相似文献   
2.
We examined the mechanisms of the inhibition of DNA synthesis by a new platinum compound, (-)-( R )-2-aminomethylpyrrolidine(1,1-cyclobutane-dicarboxylato)-2-platinum(II) monohydrate (DWA-2114R), a derivative of the antitumor drug cis- diamminedichloroplatinum(II) (CDDP), using prokaryotic and eukaryotic DNA polymerases. Preincubating activated DNA with CDDP or DWA-2114R reduced its template activity for prokaryotic and eukaryotic DNA polymerases in a dose-dependent manner. DWA2114R required six times greater drug concentration and two times longer incubation time to show the same decrease of the template activity compared to CDDP. Treatment of primed pUC118 ssDNA templates with the two drugs followed by second-strand synthesis by prokaryotic and eukaryotic DNA polymerases revealed that DWA2114R bound to DNA in a similar manner to CDDP and these adducts blocked DNA elongation by DNA polymerases of eukaryotes as well as of prokaryotes. With these two drugs, the elongations by E. coli DNA polymerase I (Klenow fragment), T7 DNA polymerase and calf thymus DNA polymerase α were strongly arrested at guanine-guanine sequences (GG). Stop bands were also observed at adenine-guanine sequences (AG) guanine-adenine-guanine sequences (GAG) and mono-guanine sequence (G). Calf testis DNA polymerase β was also arrested efficiently at AG, GAG and G, but much more weakly at GG. This pattern was common to DWA2114R and CDDP.  相似文献   
3.
Intraventricular hemorrhage (IVH) in preterm infants is well known to be associated with the high morbidity and mortality of this group. Previous studies have suggested altered cerebral blood flow (CBF) as an important pathologic factor. We measured the CBF in nearterm rabbit fetuses using the hydrogen clearance technique. The local CBF of the rabbit fetuses was significantly low compared with that of the maternal rabbits. The response of CBF to changes in PaCO2 was observed in rabbit fetuses. The CO2 reactivity index of the fetal rabbit was lower than that of the maternal rabbit. This low CO2 reactivity might reflect the immaturity of the fetal brain and its low CBF. We were unable to monitor the fetal blood pressure, but the fetal CBF remained stable when the maternal blood pressure was altered. It is well known that IVH in preterm infants originates from the subependymal germinal matrix and that this has many fragile vessels. Our observation suggests that even a small increase of CBF during hypercapnia might have a large effect towards producing hemorrhage.  相似文献   
4.
Invasive aspergillosis (IA) is a severe complication of liver transplantation. Risk factors for IA after deceased donor liver transplantation (DDLT) have been presented in several reports, but are not well established for living donor liver transplant recipients. Here, a retrospective case-control study was performed. Five cases with IA were investigated after living donor liver transplantation (LDLT) between January 1999 and December 2002 at Kyoto University Hospital. For comparison, living donor liver transplant recipients without IA were taken as controls. These patients had undergone LDLT 1 month before or after each IA case and had the same survival times as the latter. We evaluated the clinical and laboratory findings for both groups up until their demise. Patients with IA after LDLT had a very poor prognosis. By univariate analysis, risk factors for IA were preoperative intensive care unit stay (P = 0.02) and preoperative steroid administration (P = 0.02). Preoperative steroid administration for fulminant hepatitis possibly predisposed to the development of IA after LDLT.  相似文献   
5.
6.
Journal of Neurology - A high incidence of valvular heart disease in Parkinson's disease (PD) patients treated with ergot-derived dopamine agonists, such as cabergoline and pergolide, has been...  相似文献   
7.
Neuronavigation has become an effective therapeutic modality and is used routinely for intra-axial tumor removal. This retrospective study was conducted to evaluate the clinical impact of neuronavigation and image-guided extensive resection for adult patients with supratentorial malignant astrocytomas. Between 1990 and 2002, 76 adult patients with pathologically confirmed malignant astrocytomas underwent craniotomy and removal of the tumors at the Toyama Medical and Pharmaceutical University Hospital. Of these 76 patients, 42 were treated using neuronavigation with conventional microneurosurgery and the other 34 were treated with conventional microneurosurgery alone. Postoperative early MRI with contrast enhancement was done, and gross total resection was defined as the complete absence of residual tumor. Survival time was analyzed with the Kaplan-Meier method. Prognostic factors were obtained from the Cox proportional hazards model. In univariate analysis, age (< 65), grade 3, preoperative KPS (>/= 80), use of neuronavigation, and gross total resection were significantly associated with longer survival. However, when the data were submitted to multivariate analysis, grade 3, preoperative KPS (>/= 80), and gross total resection were independent prognostic factors. The median survival periods of patients receiving gross total resection (vs. partial resection) and neuronavigation (vs. no neuronavigation) were 16 (vs. 9) months and 16 (vs. 10) months, respectively. The percentage of a gross total resection was significantly higher in the neuronavigation group compared to that in the no-navigation group (64.3 % vs. 38.2 %, p < 0.05). Neurological deterioration occurred in 4 of 42 (9.5 %) and in 6 of 34 (17.6 %) patients after surgery with neuronavigation and surgery without neuronavigation, respectively, although this difference was not statistically significant. Our results showed that neuronavigation increases the radicality in the resection of malignant astrocytomas and is objectively useful for improving survival time.  相似文献   
8.
H Yamamoto  S Tsuji  Y Nagai 《Brain research》1991,558(1):117-119
We established a MAb N-25 reacted with a minor unknown antigen (AgX) in a commercially available GQ1b sample. It also recognized minor antigens in bovine brain (X-1, 2, 3, 4 and 5) and cultured neural cell lines (X-1). AgX is identical to X-5. X-5 is sialidase sensitive and has the common structure as X-1, which is resorcinol positive. These results suggested that novel gangliosides exist in bovine brain and neural cell lines.  相似文献   
9.
The thermal conversion of 1 alpha-hydroxyprevitamin D3 (1 alpha-OH-previtamin D3) diacetate to 1 alpha-hydroxyvitamin D3 (1 alpha-OH-vitamin D3) diacetate was investigated in five solvents. The fraction of 1 alpha-OH-vitamin D3 diacetate was calculated from the HPLC peak areas (UV detection) of 1 alpha-OH-previtamin D3 diacetate and 1 alpha-OH-vitamin D3 diacetate. When 1 alpha-OH-previtamin D3 diacetate was dissolved in ethanol, benzene, toluene, isopropyl ether, or n-hexane, and heated at 60 degrees C, the yield of 1 alpha-OH-vitamin D3 diacetate increased during the first 4 h, and reached an equilibrium level after 8.5 h. Differences in the ratio of 1 alpha-OH-previtamin D3 diacetate to 1 alpha-OH-vitamin D3 diacetate at thermal equilibrium, and in the rate of the thermal isomerization were observed among these five solvents. Molecular mechanics (MM) calculations were performed in order to estimate solvent effects on conformation for 1 alpha-OH-previtamin D3 diacetate and 1 alpha-OH-vitamin D3 diacetate. The solvent effect was treated by specifying a dielectric constant representative of each of the three solvents: ethanol (polar), n-hexane (nonpolar), and benzene (aromatic). The dielectric constants used were 24.3 for ethanol, 1.5 for n-hexane, and 2.3 for benzene. It is suggested that the conformation of 1 alpha-OH-vitamin D3 diacetate is stabilized in polar solvent. However, the order of conformational stability when solvent effects are included in the calculations is: ethanol greater than benzene greater than n-hexane. This order does not follow the experimental results. The proton NMR chemical shifts of 1 alpha-OH-vitamin D3 diacetate are different in deuterated n-hexane, ethanol, and benzene. The downfield shift of the C-6 vinyl proton of 1 alpha-OH-vitamin D3 diacetate, when compared to the chemical shift in benzene, is 0.15 and 0.11 ppm relative to the chemical shift in n-hexane and ethanol, respectively, and that of the C-7 proton was 0.30 and 0.33 ppm, respectively. No significant proton shift of 1 alpha-OH-previtamin D3 diacetate is recorded in these three solvents. To account for the increased ratio of 1 alpha-OH-vitamin D3 diacetate to 1 alpha-OH-previtamin D3 diacetate ratio in benzene, we suggest that 1 alpha-OH-vitamin D3 diacetate may be stabilized via specific solute-solvent interactions in benzene.  相似文献   
10.
Sixteen malignant tumors of soft tissue (15 cases) were treated with low voltage direct current (DC therapy) with or without systemic chemotherapy. Two platinum or stainless steel electrodes were placed in the tumor and around 10 volts of direct current was passed for 1 hour. In cases in which chemotherapy was performed, single or combined anticancer agents consisted of ADM and BLM were administered simultaneously with DC therapy by systemic route. Ten cases (11 tumors) out of 15 cases received no other local treatment. Histological examination was performed in 6 of 11 lesions, and in all lesions pathological therapeutic effects were recognized. Decrease in tumor size was observed in 9 lesions. In 2 cases the tumors disappeared completely after DC therapy only. In one case receiving DC therapy with chemotherapy, the tumor decreased dramatically and became resectable. Main complications were slight pain during treatment and slight fever after treatment, but special treatment for these complications was not necessary. Our results suggested that DC therapy with or without systemic chemotherapy was useful for local control of malignant tumors. And also if DC therapy had been performed simultaneously with chemotherapy the therapeutic effects seemed to be more emphasized than single use of these therapies.  相似文献   
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