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61.
Q Li W Wang KB Berst A Claiborne L Hasvold K Raye M Tufano A Nilius LL Shen R Flamm J Alder K Marsh D Crowell DT Chu JJ Plattner 《Canadian Metallurgical Quarterly》1998,8(15):1953-1958
The 8-position side chain of 2-pyridones is believed to be involved in the binding with bacterial DNA gyrase to form the ternary complex, making them very important for the activity of 2-pyridones. A series of 2-pyridones having fluoro-substituted amines at the 8-position has been synthesized and their antibacterial activities and parmacokinetic properties are reported. 相似文献
62.
H Kino H Inaba N Van De L Van Chau DT Son HT Hao ND Toan LD Cong M Sano 《Canadian Metallurgical Quarterly》1998,29(2):250-254
We present the spatial structure of binase, a small extracellular ribonuclease, derived from 1H-NMR* data in aqueous solution. The total of 20 structures were obtained via torsion angle dynamics using DYANA program with experimental NOE and hydrogen bond distance constraints and phi and chi1 dihedral angle constraints. The final structures were energy minimised with ECEPP/2 potential in FANTOM program. Binase consists of three alpha-helices in N-terminal part (residues 6-16, 26-32 and 41-44), five-stranded antiparallel beta-sheet in C-terminal part (residues 51-55, 70-75, 86-90, 94-99 and 104-108) and two-stranded parallel beta-sheet (residues 22-24 and 49-51). Three loops (residues 36-39, 56-67 and 76-83), which play significant role in biological functioning of binase, are flexible in solution. The differences between binase and barnase spatial structures in solution explain the differences in thermostability of binase, barnase and their hybrids. 相似文献
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DT Chua JS Sham D Choy V Lorvidhaya Y Sumitsawan S Thongprasert V Vootiprux A Cheirsilpa T Azhar AH Reksodiputro 《Canadian Metallurgical Quarterly》1998,83(11):2270-2283
BACKGROUND: The aim of this trial was to compare the outcome achieved with neoadjuvant chemotherapy followed by radiotherapy to that achieved with radiotherapy alone for patients with locoregionally advanced undifferentiated or poorly differentiated nasopharyngeal carcinoma (NPC) meeting one of the following criteria: Ho's T3 disease, Ho's N2-N3 disease, or lymph node size > or =3 cm. METHODS: Between September 1989 and August 1993, 334 patients were enrolled in the study, with equal numbers of patients randomized to the neoadjuvant chemotherapy arm (CT arm) and the radiotherapy arm (RT arm). Neoadjuvant chemotherapy consisting of 2-3 cycles of cisplatin (60 mg/m2 on Day 1) and epirubicin (110 mg/m2 on Day 1) followed by radiotherapy was given to the CT arm. For radiotherapy, a dose of 66-74 gray (Gy) (median, 71 Gy) was delivered to the primary tumor and 60-76 Gy (median, 66 Gy) to the neck. Two hundred eighty-six eligible patients completed the treatment and were evaluable for treatment response (134 in the CT arm, 152 in the RT arm). All patients were included in the survival analysis based on the intention to treat. The median follow-up was 30 months for the whole cohort and 41 months for the surviving patients. RESULTS: Analysis of the 334 patients based on the intention to treat showed no significant difference in relapse free survival (RFS) or overall survival (OS) between the 2 treatment arms (3-year RFS rate: 48% in the CT arm vs. 42% in the RT arm, P = 0.45; 3-year OS rate: 78% vs. 71%, P = 0.57). In an efficacy analysis based on only the 286 evaluable patients, a trend of improved RFS favoring the CT arm was observed (3-year RFS rate: 58% vs. 46%, P = 0.053), with again no significant difference in OS (3-year OS rate: 80% vs. 72%, P = 0.21). In the subgroup of 49 patients with bulky neck lymph nodes >6 cm, improved RFS (3-year RFS rate: 63% vs. 28%, P = 0.026) and OS (3-year OS rate: 73% vs. 37%, P = 0.057) were observed, favoring the CT arm. CONCLUSIONS: This multicenter randomized study did not demonstrate any benefit with the addition of cisplatin-epirubicin neoadjuvant chemotherapy for patients with locoregionally advanced nasopharyngeal carcinoma; therefore routine administration of neoadjuvant chemotherapy to this target group cannot be recommended. Although the overall incidence of recurrence was reduced with the addition of chemotherapy in the efficacy analysis, the overall survival was not affected. A more effective chemotherapy regimen, the selection of an appropriate target group, and the use of an alternative strategy for combining chemoradiotherapy should be explored in future trials. 相似文献
64.
Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States 总被引:3,自引:0,他引:3
RC Lawrence CG Helmick FC Arnett RA Deyo DT Felson EH Giannini SP Heyse R Hirsch MC Hochberg GG Hunder MH Liang SR Pillemer VD Steen F Wolfe 《Canadian Metallurgical Quarterly》1998,41(5):778-799
OBJECTIVE: To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain). METHODS: The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020. RESULTS: Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form of arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected. CONCLUSION: Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population. 相似文献
65.
The diagnosis of small bowel cancer before it has metastasized continues to be a clinical and radiologic dilemma. This article presents an overview of the role of radiology in the diagnosis of small bowel cancer, describes techniques for optimal radiologic examination, and presents a pictorial essay of the radiologic features and differential diagnoses of these tumors. 相似文献
66.
Highly sialylated gangliosides have been shown to alter cellular adhesion to a fibronectin matrix. The effect of these gangliosides on the adhesion, spreading, and migration of cultured keratinocytes on a fibronectin matrix has not been explored. Ganglioside GT1b significantly prevented attachment of keratinocytes to fibronectin and also detached previously adherent keratinocytes in a concentration-dependent manner without cell toxicity. GT1b did not affect adhesion of keratinocytes to wells coated with laminin, type I or type IV collagen, 804G extracellular matrix, or albumin. GT1b also inhibited keratinocyte migration on fibronectin in a concentration-dependent manner at concentrations as low as 5 nM GT1b, but had no effect on migration of keratinocytes plated on other matrices. GT1b binds to intact fibronectin and to the 120-kD RGDS-containing cell-binding fibronectin fragment, but not to the heparin- or gelatin-binding fragments of fibronectin. Although RGDS competes with GT1b in inhibiting adhesion, GT1b does not diminish binding of keratinocytes to a derivatized RGDS substratum, suggesting that the GT1b effect involves a non-RGDS site in the cell-binding region that modulates RGDS/alpha 5 beta 1 integrin receptor interaction. Through a specific effect on keratinocyte interaction with fibronectin, GT1b may participate in the regulation of cell adhesion and migration on a fibronectin substratum, which are important events during wound healing and the spreading of cutaneous neoplasia. 相似文献
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