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排序方式: 共有4549条查询结果,搜索用时 31 毫秒
51.
Jae Chul Jung Ju Cheun Kim Oee Sook Park Bong Suek Jang 《Archives of pharmacal research》1999,22(3):302-305
An efficient procedure for the preparation of 4-hydroxy-3-{1,2,3,4-tetra-hydro-3-[4-(4-triflu-oromethylbenzyl oxy)phenyl]-1-naphthyl}thiocoumarin (thioflocoumafen, 1a and 1b) is described. The key step in the synthesis involves the condensation reaction of 3-(4-methoxyphenyl)-1-tetralol (2) with 4-hydroxy-1-thiocoumarin (3). 相似文献
52.
Aliphatic esters of protocatechuic acid (PA,1), vanillic acid (VA,9) and gallic acid (GA,18) were prepared and their anti-thrombotic effects were evaluated in the mouse model of thrombosis. The aliphatic groups included methyl, ethyl,n-propyl,i-propyl,n-butyl,i-butyl,n-amyl and cyclohexyl.n-Amyl ester of PA (7), i-propyl and cyclohexyl esters of VA (13 and17 respectively) and ethyl ester of GA (20) treatment significantly lowered the death rate and increased the recovery from paralysis due to the thrombotic challenge. From the limited analogs available, it was tentatively concluded that the structural conformation, where carboxy oxygen (=O or-O?) of the carboxyl group (COOH) at C1 and the oxygen function at C3 (either OH or OCH3) are closely situated, is favorable for the esters of PA, VA and GA to be more antithrombotic. 相似文献
53.
The prevalence of microalbuminuria was assessed in 50 patients of non-insulin dependent diabetes mellitus. The mean age of patients was 52.1 ± 11.6 years and the duration of diabetes was 8.3 ± 6.8 years. Twenty (40%) patients had microalbuminuria. Microalbuminuria was more common in patients with a longer duration of diabetes (more than 5 years), a poor glycaemic control, and higher systolic blood pressure.KEY WORDS: Microalbuminuria, Diabetes mellitus, Diabetic nephropathy, Chronic renal failure 相似文献
54.
Expression of placental growth factor gene in lung cancer. 总被引:4,自引:0,他引:4
In Sook Woo Myung Jae Park Jae Ho Byun Young Seon Hong Kyung Shik Lee Young Suk Park Jung Ae Lee Young Iee Park Hye-Kyung Ahn 《Tumour biology》2004,25(1-2):1-6
Differences in the gene expression profiles in small cell lung cancers (SCLC) and non-small cell lung cancers (NSCLC) may explain their different clinical characteristics. The aims of this study were (1) to identify genes differentially expressed in SCLC and NSCLC using mRNA differential display, and (2) to determine the clinical relevance of such genes in lung cancer. RNA differential display using three SCLC and six non-SCLC cell lines was used to identify a differentially expressed gene. Differential expression of the gene was confirmed in additional lung cancer cell lines using RT-PCR. Immunohistochemical staining for the gene product was performed on paraffin-embedded tissue from lung cancer patients. We examined the relationship between the expression of the gene and clinical parameters, including disease stage, response to treatment and survival time. The placental growth factor (PGF) gene was identified as preferentially expressed in SCLC compared with NSCLC cell lines using mRNA differential display. Further analysis of 45 lung cancer cell lines using RT-PCR showed that the placental growth factor (PGF) gene was expressed in nine of 13 SCLC cell lines (69%) and five of 32 NSCLC cell lines (15.6%) (p < 0.001, Fisher's exact test). Immunohistochemistry using anti-PGF antibody on the paraffin blocks from lung cancer patients showed that PGF expression was significantly higher in SCLC than NSCLC tissue sections (32 vs. 5.6%, p = 0.041, Fisher's exact test). Expression of PGF protein did not correlate with disease stage, response to treatment or survival time in SCLC patients. The present study suggests there is higher expression of PGF in SCLC compared to NSCLC. It may be that higher expression of the angiogenic factor PGF contributes to differences between the progression of SCLC and NSCLC, especially in regard to the nature of SCLC metastasis. 相似文献
55.
A nationwide study of intracellular drug metabolite concentrations in children prescribed 6-mercaptopurine for the treatment of lymphoblastic leukaemia was carried out to assess interpatient variability at a standardised dose. Nine children (2% of the total) had completely undetectable metabolites, indicative of non-compliance. Five were adolescents, but otherwise they had no obvious distinguishing characteristics. Not taking any 6-mercaptopurine at all is uncommon, but the problem cannot be predicted. The total number of children who do not comply cannot be determined from this study, but the nine children described represent only a fraction of these. 相似文献
56.
Jung Sook Seo Kyung Mi Yang Jung Mi Kim Hyesun Min Chang Su Kim Betty J. Burri 《Nutrition Research》2004,24(12):959-968
This human study was conducted to evaluate the effect of chronic alcohol consumption on plasma concentrations of lipid and the antioxidative system in 44 Korean alcoholics and 45 age-, sex-, and nationality-matched nonalcoholic subjects. Plasma triacylglycerols and atherogenic index were higher in alcoholics than in control subjects. Plasma total cholesterol was not different among groups, but plasma high-density lipoprotein cholesterol was lower in alcoholics. There were positive correlations between ethanol consumption and plasma lipid peroxide and atherogenic index in all subjects; there were negative correlations between ethanol consumption and plasma high-density lipoprotein cholesterol in all subjects. There were no significant differences between alcoholics and control subjects in plasma concentrations of α-tocopherol, although plasma α-tocopherol/lipid tended to be lower in alcoholics. Plasma retinol was lower in alcoholics. These results suggest that chronic ethanol consumption can contribute to increased risk for vascular diseases in Korean alcoholics. 相似文献
57.
Zhao P Cao J Zhao LJ Qin ZL Ke JS Pan W Ren H Yu JG Qi ZT 《第二军医大学学报》2006,27(5):506-506
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein. 相似文献
58.
Dahae Won Chan‐Jeoung Park Hyoeun Shim Seongsoo Jang Hyun‐Sook Chi Jooryung Huh Dok Hyun Yoon Cheolwon Suh 《Histopathology》2013,62(3):397-405
Aims: Bone marrow (BM) biopsies of some mucosa‐associated lymphoid tissue (MALT) lymphoma patients show scattered or small clusters of CD20+ cells without definite lesions (subtle CD20 positivity). The aim of this study was to evaluate the clinical significance of BM involvement and subtle CD20 positivity in 122 patients diagnosed with MALT lymphoma. Methods and results: Patients were divided into three categories: BM involvement [BM(+)], subtle CD20 positivity, and no BM involvement [BM(?)]. Eleven (9%) showed BM involvement, and 17 (14%) showed subtle CD20 positivity. BM(+) patients had significantly worse progression‐free survival (PFS) than BM(?) patients [hazard ratio (HR) 6.25, P = 0.01], but there was no significant difference between subtle CD20 positivity and BM(?) patients. Patients with >30 CD3+ cells among 100 nucleated cells in the areas with increased numbers of CD3+ cells had significantly worse PFS than those with <15 CD3+ cells (HR 5.49, P = 0.02). BM(+) patients with >30 CD3+ cells had worse PFS than those with ≤30 CD3+ cells (P = 0.029), with an extent of BM(+) involvement of >10% positively correlating with >30 CD3+ cells (P = 0.015). Conclusions: Patients with BM(+) MALT lymphoma showed significantly worse PFS than those with subtle CD20 positivity and BM(?) MALT lymphoma, but the PFS of patients with subtle CD20 positivity MALT lymphoma was not significantly different from that of those with BM(?) MALT lymphoma. Increased numbers of BM T cells in MALT lymphoma patients might be suggestive of a worse prognosis. 相似文献
59.
Here, we propose an integrated multifunctional system constructed by conductive disulfide-biotin-doped polypyrrole nanowires (SS-biotin-Ppy NWs) for capture, release, and in situ quantification of circulating tumor cells (CTCs). A well-ordered three-dimensional nanowire structure equipped with a monoclonal antibody offers a significant impact on the cell-capture efficiency, as well as on electrical- or glutathione (GSH)-mediated release of the captured cells. In addition, the electrochemical identification/detection of the captured cancer cells can be directly conducted on the same Ppy NW platform by using horseradish peroxidase (HRP)-labeled and anti-EpCAM-conjugated nanoparticles (HRP/anti-EpCAM Ppy NPs), showing very high sensitivity and specificity. The signal amplification can be clearly attributed to the catalytic response resulting from enzymatic reduction of hydrogen peroxide on Ppy NWs, consequently generating a greatly increased amperometric response with a detection range of 10 to 1 × 104 cells and a detection limit of as low as 10 cells. Overall, the proposed Ppy NWs not only present a promising platform for effective cell capture and release but also permit cytosensing capability for on-site analysis. 相似文献
60.
William T.H. Lim Ean H. Ooi Ji J. Foo Kwan H. Ng Jeannie H.D. Wong Sook S. Leong 《Ultrasound in medicine & biology》2021,47(8):2033-2047
Early detection of chronic kidney disease is important to prevent progression of irreversible kidney damage, reducing the need for renal transplantation. Shear wave elastography is ideal as a quantitative imaging modality to detect chronic kidney disease because of its non-invasive nature, low cost and portability, making it highly accessible. However, the complexity of the kidney architecture and its tissue properties give rise to various confounding factors that affect the reliability of shear wave elastography in detecting chronic kidney disease, thus limiting its application to clinical trials. The objective of this review is to highlight the confounding factors presented by the complex properties of the kidney, in addition to outlining potential mitigation strategies, along with the prospect of increasing the versatility and reliability of shear wave elastography in detecting chronic kidney disease. 相似文献