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991.
A 41-year-old male presented with an ill-demarcated mass involving the left fronto-temporal lobe and the basal ganglia. Light microscopically the tumor was diagnosed as an anaplastic oligoastrocytoma. Electron microscopy revealed several cytoplasmic crystalline inclusions in tumor cells of oligodendroglial lineage. No crystalline inclusions were membrane bound. The morphologic features with unique ultrastructural findings are presented. 相似文献
992.
慢性肾衰患者外周血IL-18水平及血液透析对其的影响 总被引:6,自引:0,他引:6
为探讨慢性肾衰竭 (CRF )患者外周血IL 18表达量的变化以及血液透析 (HD )对其表达的影响 ,选取 10名健康志愿者及 2 9例CRF患者 ,应用ELISA测定血浆IL 18水平 ,同时采用半定量逆转录多聚酶链反应 (RT PCR )技术 ,检测PBMC中IL 18mRNA表达量。结果是未行HD的CRF患者血浆IL 18水平及PBMCIL 18mRNA表达量较正常对照组增高 ,差异有显著统计学意义 (P <0 0 1) ,单次HD对CRF患者血浆IL 18水平及基因表达无明显影响 (P >0 0 5 ) ,但长期维持HD则可使CRF患者外周血IL 18水平及基因表达增高 (P <0 0 5 )。提示外周血IL 18的高表达可能参与CRF的发病过程及HD相关并发症的发生发展 相似文献
993.
Ok-Sub Lee Byung-Jo Ha Soo-Nam Park Yoon-Sik Lee 《Macromolecular chemistry and physics.》1997,198(9):2971-2976
Chitosan/calcium-alginate beads were prepared by a coacervation method in aqueous medium. Their swelling properties and morphologies were studied. Complexed beads with a mean diameter of 500 μm were obtained by dropwise addition of a sodium alginate solution into a chitosan-calcium chloride solution. From scanning electron microscopic studies, we observed that chitosan modifies the morphology of calcium-alginate beads. The swelling properties of chitosan/calcium-alginate beads are different from those of calcium-alginate beads. In the case of the calcium-alginate beads, the swelling volume increases as the pH of the medium increases. However, chitosan/calcium-alginate beads show a maximum swelling volume at pH 9.0. 相似文献
994.
Status of hepatitis B virus DNA in hepatocellular carcinoma: a study based on paired tumor and nontumor liver tissues 总被引:1,自引:0,他引:1
M Y Lai D S Chen P J Chen S C Lee J C Sheu G T Huang T C Wei C S Lee S C Yu H C Hsu 《Journal of medical virology》1988,25(3):249-258
To investigate the hepatitis B virus (HBV) DNA status in the liver when hepatocellular carcinoma (HCC) has developed, 35 paired nontumorous and tumorous liver tissues from 27 hepatitis B surface antigen (HBsAg)-seropositive and 8 HBsAg-negative patients with HCC were studied by Southern blot analysis. The hybridization patterns of HBV DNA were different in the nontumor and tumor parts in 26 (96.3%) of the 27 HBsAg-positive patients. In the nontumor parts, integration of HBV DNA into the host genome was significantly less when compared to the tumor parts (15/27 vs. 25/27, P less than 0.05), whereas free replicative viral forms were significantly more frequent (17/27 vs. 7/27). The integrated HBV DNA in the nontumor parts showed discrete band patterns in the majority of cases (13/15). Hepatitis B e antigen (HBeAg) was significantly associated with the expression of free replicative forms of HBV DNA in the tumor tissues. An integrated HBV DNA sequence was detected in the tumor part of one HBsAg-negative patient, but not in her nontumor counterpart. Our observation that discrete integrated HBV DNAs are present in the nontumor part, representing subclinical clonal expansion that precedes the development of HCC, suggests the risk of future new tumor growth from these cell clones. 相似文献
995.
M Lee S Park J S Han Y Y Lee H Y Lee K C Kye B K Kim J S Lee 《Journal of Korean medical science》1986,1(1):53-58
Twenty male patients with Korean hemorrhagic fever were evaluated with thrombelastography (TEG) to assess the changes in coagulation system, and the results were compared with those of conventional coagulation tests. Procoagulant activity in the plasma was determined by comparing the reaction time "r" of the normal plasma and that of the mixture of equal parts of the normal plasma and the patient's plasma. The TEG was found to be a useful measure of the changes in the coagulation profile, and provided instant accurate assessment of the patient's hemostatic function. Presence of the procoagulant activity was demonstrated in the plasma of the patients and indicated occurrence of active intravascular coagulation during the early stage of the disease. 相似文献
996.
Ahn HW Shin WG Park KJ Suh OK Choi JH 《Research communications in molecular pathology and pharmacology》1999,105(1-2):105-113
Theophylline has been widely used to treat apnea of premature neonates. The purpose of this study was to compare the pharmacokinetic parameters of theophylline and caffeine after intravenous administration of aminophylline to seven Korean low-birthweight neonates with apnea to those in other countries. The serum concentrations of theophylline and caffeine were measured simultaneously by high-performance liquid-chromatography (HPLC). The mean (+/- S.E.M.) birth weight and gestational period were 1190 +/- 253 g and 31.5 +/- 1.99 weeks, respectively. The mean (+/- S.E.M.) theophylline maintenance dosage was 1.28 +/- 0.15 mg/kg (given as equivalent aminophylline solution) every six hours. The mean (+/- S.E.M.) volume of distribution, 0.937 +/- 0.232 l/kg, elimination rate constant, 0.0249 +/- 0.0095/h, elimination half-life, 32.1 +/- 12.1 h, and total body clearance, 21.7 +/- 6.18 ml/h/kg, of theophylline in Korean premature neonates were comparable to the values of neonates in other countries. For caffeine, the mean (+/- S.E.M.) elimination half-life was 95.1 +/- 25.4 h and the elimination rate constant was 0.0079 +/- 0.0024/h. The mean (+/- S.E.M.) serum concentrations of theophylline and caffeine on the sixth day after aminophylline infusion were 10.4 +/- 2.28 microg/ml (range, 6.38-13.4 microg/ml) and 2.94 +/- 0.98 microg/ml (range, 1.80-4.44 microg/ml), respectively. The mean (+/- S.E.M.) caffeine to theophylline concentration ratio on the day after discontinuation of aminophylline infusion was 0.71 +/- 0.23 (range, 0.39-1.03). 相似文献
997.
Lee KW Yun T Song EK Na II Shin H Bang SM Lee JH Lee ST Kim JH Yoon SS Lee JS Park S Kim BK Kim NK 《Journal of Korean medical science》2005,20(4):598-562
Recent clinical trials showed that bortezomib, a novel proteasome inhibitor, had therapeutic activity in multiple myeloma. However, there was no data about the feasibility of bortezomib in Korean patients. We performed a pilot study of bortezomib in patients with relapsed or refractory myeloma (1.3 mg/m2 twice weekly for 2 week in a 3-week cycle). Seven patients were enrolled. The median age of patients was 59 yr. All patients previously received VAD (vincristine, doxorubicin and dexamethasone) and thalidomide chemotherapy. Three patients previously received alkylator-containing chemotherapy and 4 patients, autologous stem cell transplantation. Bortezomib monotherapy resulted in 3 partial remissions (43%), 3 no changes (43%) and 1 progressive disease (14%). One patient who had no response to bortezomib monotherapy experienced partial remission after addition of dexamethasone to bortezomib. The most common serious toxicity was thrombocytopenia (grade 3/4, 10 of 20 cycles (50%)) and grade 3 peripheral neuropathy was developed in 2 of 20 cycles (10%). Drug-related adverse event led to discontinuation of bortezomib in 1 patient. There was no treatment related mortality. Overall, bortezomib seems to be effective and feasible. Conduction of larger clinical studies on Korean patients is necessary to characterize clinical efficacy and safety of bortezomib more precisely. 相似文献
998.
Mice of three haplotypes (H-2d, H-2b, and H-2d/b) were immunized with synthetic HPV16 virus-like particles (VLPs), produced using a vaccinia virus doubly recombinant for the L1 and L2 proteins of HPV16. The resultant anti-VLP antisera recognized HPV16 capsids by ELISA assay and baculovirus recombinant HPV16 L1 and L2 protein on immunoblot. Overlapping peptides corresponding to the HPV16 L1 amino acid sequence were used to define the immunoreactive regions of the L1 protein. The majority of the L1 peptides were reactive with IgG from the mice immunized with the synthetic HPV16 capsids. A computer algorithm predicted seven B epitopes in HPV16 L1, five of which lay within peptides strongly reactive with the murine antisera. The murine anti-VLP antisera failed to react with the two peptides recognized by anti-HPV16L1 monoclonal antibodies raised by others against recombinant L1 fusion protein. We conclude that the immunoreactive epitopes of HPV16 defined using virus-like particles differ significantly from those defined using recombinant HPV16 L1 fusion proteins, which implies that such fusion proteins may not be the antigens to look for HPV16L1 specific immune responses in HPV-infected patients. 相似文献
999.
Thomas H-Y Leung Nathalie Wong Paul B-S Lai Andrew Chan Ka-Fai To Choong-Tsek Liew Wan-Yee Lau Philip J Johnson 《Modern pathology》2002,15(11):1213-1220
Frequent chromosome 1 abnormalities detected in human hepatocellular carcinoma have been implicated in early genetic events of liver carcinogenesis. Recurrent loss of 1p with a common deleted region 1p36-p34 has been reported from microsatellite analysis, whereas common gain of the whole chromosome q-arm was described from several comparative genomic hybridization studies. The relationships between copy number changes and allelic status however remains unclear. In this study, we have conducted a simultaneous comparative genomic hybridization and microsatellite analysis study on chromosome 1 in 31 hepatocellular carcinoma cases. Microsatellite analysis revealed frequent loss of heterozygosity on 1p at loci D1S468 (74%), D1S450 (67%), D1S2667 (65%), D1S2697 (75%), D1S199 (52%), and D1S234 (67%) corresponded to the distal 1p36 region and coincided with 12 cases (86%) that presented losses on 1p by comparative genomic hybridization analysis. Although comparative genomic hybridization indicated a common deleted region of 1p36-p35 in the current series, microsatellite analysis has refined the smallest overlapping region (SOR) to 1p36.13-p36.22. Gain of 1q as revealed by comparative genomic hybridization suggested low and high-level gains, and cases that displayed an amplicon below the heterochromatic region 1q21-q25. Common allelic imbalances of polymorphic markers D1S2635 (64%), D1S484 (67%), D1S2878 (65%), D1S196 (70%), D1S249 (64%) D1S2785 (75%), D1S2842 (73%) and D1S2836 (74%) that corresponded to the regions 1q23.1-q24.2, 1q32.1 and 1q43-q44 were detected. Three distinct regions of allelic imbalances were thus suggested on recurring 1q gain found in hepatocellular carcinoma. Furthermore, microsatellite analysis has enabled a mapping of common overrepresented regions and suggested SOR on 1q23.1-q23.3 (D1S2635-D1S2878), 1q25.1-q31.1 (D1S452-D1S238), and 1q43 (D1S2785-D1S2842). Our current study has refined chromosome 1 aberrations in hepatocellular carcinoma to four regions of allelic imbalances. The SORs delineated should provide basis for further molecular investigation in hepatocarcinogenesis on genes residing on these chromosomal regions. 相似文献
1000.
Rapid identification of Candida dubliniensis using a species-specific molecular beacon 总被引:3,自引:0,他引:3 下载免费PDF全文
Park S Wong M Marras SA Cross EW Kiehn TE Chaturvedi V Tyagi S Perlin DS 《Journal of clinical microbiology》2000,38(8):2829-2836
Candida dubliniensis is an opportunistic fungal pathogen that has been linked to oral candidiasis in AIDS patients, although it has recently been isolated from other body sites. DNA sequence analysis of the internal transcribed spacer 2 (ITS2) region of rRNA genes from reference Candida strains was used to develop molecular beacon probes for rapid, high-fidelity identification of C. dubliniensis as well as C. albicans. Molecular beacons are small nucleic acid hairpin probes that brightly fluoresce when they are bound to their targets and have a significant advantage over conventional nucleic acid probes because they exhibit a higher degree of specificity with better signal-to-noise ratios. When applied to an unknown collection of 23 strains that largely contained C. albicans and a smaller amount of C. dubliniensis, the species-specific probes were 100% accurate in identifying both species following PCR amplification of the ITS2 region. The results obtained with the molecular beacons were independently verified by random amplified polymorphic DNA analysis-based genotyping and by restriction enzyme analysis with enzymes BsmAI and NspBII, which cleave recognition sequences within the ITS2 regions of C. dubliniensis and C. albicans, respectively. Molecular beacons are promising new probes for the rapid detection of Candida species. 相似文献