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91.
Hepatitis C virus (HCV) nonstructural (NS) proteins appeared to be important targets for HCV vaccine development, since NS-specific T-helper-cell responses are associated with clearance from acute HCV infection. In this report, we have constructed a plasmid, pTV-NS345, that encodes the HCV NS3, NS4 and NS5 proteins (NS345) and a bicistronic plasmid, PTV-NS345/GMCSF, in which the HCV NS345 polyprotein and GMCSF are translated independently. Intramuscular inoculation with pTV-NS345 plasmid DNA into the Buffalo rats generated both antibody and T-cell proliferative responses to each NS protein. The expression of GMCSF, together with HCV NS345 proteins, appeared to significantly increase T-cell proliferative responses. In particular, the inoculation of a bicistronic plasmid generated higher T-cell proliferative responses to each NS protein than did the coinjection of two separate plasmids, pTV-NS345 and pTV-GMCSF. These results demonstrate that the codelivery of GMCSF augmented HCV NS345-specific cellular immunity and that the intensity of the immunity was differed depending on how GMCSF gene is codelivered. 相似文献
92.
A series of 4-amino Capsaicin analogs 15, 17 and 19 were prepared to investigate the bioisosteric effect of 4-amino group, and all these compounds exhibited moderate or weak potency from their analgesic test. From our previous results and others, 4-hydroxyl group as well as 3-methoxy substituent could be crucial for high analgesic activity. This biological result also shows that the activity is sensitive to alkyl chain length in hydrophobic region and the phenylacetic amides 19 are more active than the corresponding urea derivatives 17. 相似文献
93.
Hak Cheol Kwon Byeong Gon Lee Seung Hee Kim Chil Mann Jung Sung Youl Hong Jeung Whan Han Hyang Woo Lee Ok Pyo Zee Kang Ro Lee 《Archives of pharmacal research》1999,22(4):410-413
In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two beta-carboline alkaloids, 4-methoxy-1-vinyl-beta-carboline (1) and 4,8-dimethoxy-l-vinyl-beta-carboline (2) have been isolated from the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed marked inhibitory activity of iNOS on LPS- and interferon-gamma-stimulated RAW 264.7 cells. 相似文献
94.
Sung Sil Lee Sohng Ph.D. 《Community mental health journal》1996,32(2):135-148
The development of innovative alternatives to nursing homes is critical, especially in the context of OBRA mandates and the growing geriatric population. This article examines the experience of one urban county in Washington State in providing supported housing for the OBRA-affected mentally ill elderly. The significance of this demonstration project is its bold new approach in applying this emerging model to the elderly. It illustrates the perspectives and experience of both consumers and care-givers in implementing the supported housing approach, and the tensions between consumer preferences and staff, organizational and funding constraints. 相似文献
95.
Regulation of sulfate uptake in carrot cells: Properties of a hypercontrolled variant 总被引:2,自引:0,他引:2 下载免费PDF全文
Furner IJ Sung ZR 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(4):1149-1153
Sulfate uptake in haploid carrot cultures can be experimentally controlled by the sulfur source provided for growth. The rate of sulfate uptake is low in cells grown on cystine or sulfate and high in sulfur-starved cells. A selenate-resistant variant cell line has been isolated from a haploid carrot line. The variant shows hypersuppression of sulfate uptake by cystine and essentially normal control by the other treatments. While both lines efflux intracellular sulfate in the presence of external sulfate, the rate of efflux from the variant is 4-6 times higher at comparable levels of initial intracellular sulfate. Further, properties of the efflux and uptake in both lines suggest that they are mediated by the same system. We propose that the variant possesses an altered uptake-efflux system that is more readily reversed and more subject to control by some metabolite derived from cystine. 相似文献
96.
Histoclinical Analysis of Early Colorectal Cancer 总被引:5,自引:0,他引:5
To evaluate the clinicopathologic characteristics of early colorectal cancer (ECC), histopathologic and clinical features
of 90 ECC patients who underwent surgical resection (not including the endoscopic polypectomized cases) and 1704 patients
with advanced colorectal cancer were analyzed. Smaller size, better histologic differentiation, less lymph node (LN) metastasis,
and better clinical outcome were observed in those with ECC than in patients with more advanced lesions. LN metastasis was
found in 5 patients with ECC among the 56 patients who underwent bowel resection (8.9%). Tumors with LN metastasis were more
frequently associated with deep submucosal invasion, absence of an adenomatous component within the tumor, sessile configuration,
and lymphovascular invasion. Tumors showing deep submucosal layer invasion were associated with a more unfavorable histologic
grade, lymphovascular invasion, LN metastasis, sessile morphology, and absence of an adenomatous component within the tumor.
Recurrence was observed in two patients who underwent local excision for their submucosal cancer. One of the patients was
salvaged after bowel resection, but one patient died of distant metastasis. From our data analysis and literature review,
extensive submucosal invasion, lymphovascular invasion, sessile configuration, and tumors with no adenomatous component should
be considered high risk factors for LN metastasis and recurrence after limited therapy. 相似文献
97.
Factors associated with aneurysm size in patients with subarachnoid hemorrhage: effect of smoking and aneurysm location 总被引:2,自引:0,他引:2
OBJECTIVE: Intracranial aneurysm size is an important determinant of risk of rupture and outcome after rupture. Risk factors influencing aneurysm formation and growth are not well defined. In this study, we examined the association between known risk factors for cerebrovascular disease and size of intracranial aneurysms in patients with aneurysmal subarachnoid hemorrhage. METHODS: We analyzed prospectively collected data from the placebo-treated group in a multicenter clinical trial conducted at 54 neurosurgical centers in North America. The presence, location, and size of intracranial aneurysms were determined by review of the admission angiograms. Pertinent information regarding the presence of various cerebrovascular risk factors was collected for each patient. Using logistic regression analysis, we identified independent determinants of aneurysm size from demographic, clinical, and angiographic characteristics of the participants. The impact of aneurysm size on 3-month mortality was analyzed after adjusting for potential confounding factors. RESULTS: For 298 patients admitted with subarachnoid hemorrhage, the ruptured aneurysms were graded as small (<13 mm) in 235 patients (79%) and large (> or =13 mm) in 63 patients (21%). In the logistic regression model, both smoking at any time (odds ratio, 2.2; 95% confidence interval, 1.1-4.5) and middle cerebral artery origin (odds ratio, 2.5; 95% confidence interval, 1.3-4.9) were independently associated with large aneurysms. Neither hypertension, diabetes mellitus, nor alcohol and illicit drug use were associated with large-sized aneurysms. After adjusting for initial Glasgow Coma Scale score and age in the logistic regression model, the presence of large-sized aneurysms was independently associated with 3-month mortality (odds ratio, 2.3; 95% confidence interval, 1.1-4.8). CONCLUSION: Cigarette smoking and middle cerebral artery origin seem to increase the risk for developing large aneurysms in patients predisposed to intracranial aneurysm formation. Further studies are required to investigate the mechanism underlying the association between cigarette smoking and intracranial aneurysm formation. 相似文献
98.
99.
Loss of beta-catenin expression in metastatic gastric cancer. 总被引:10,自引:0,他引:10
Matthias P A Ebert Jun Yu Juliane Hoffmann Alba Rocco Christoph R?cken Sabine Kahmann Oliver Müller Murray Korc Joseph J Sung Peter Malfertheiner 《Journal of clinical oncology》2003,21(9):1708-1714
PURPOSE: Beta-catenin (beta-catenin) participates in intercellular adhesion and is an integral part of the Wnt signaling pathway. The role of beta-catenin in the pathogenesis of gastric cancer and its metastasis is largely unknown. PATIENTS AND METHODS: Immunohistochemistry and Western blot analysis were used to analyze the expression of beta-catenin in 87 human gastric cancers, in metastasis and cancer cell lines. The beta-catenin and the adenomatous polyposis coli (APC) genes were analyzed for gene mutations. Furthermore, methylation of the beta-catenin promoter in cell lines was assessed by treatment with 5'-azadeoxycytidine and sodium bisulfite genomic sequencing. RESULTS: beta-Catenin expression was present at either the cell membrane or the cytoplasm in 34 of 75 primary gastric cancers. Expression of beta-catenin was significantly more frequent in intestinal-type (P =.0049) and well-differentiated gastric cancers (P <.001). There were no quantitative differences between gastric cancers and the nonmalignant gastric tissues, as determined by Western blot analysis. One of 18 metastatic cancer lesions and four of five gastric cancer cell lines expressed beta-catenin protein. N87 cells, derived from the liver metastasis of a gastric cancer, did not express beta-catenin. Treatment with 5'-azadeoxycytidine restored beta-catenin protein levels in this cell line, which exhibited significantly more 5-methylcytosines in the beta-catenin promoter compared with the other cell lines. CONCLUSION: beta-Catenin expression is lost in a subgroup of primary gastric cancers, is frequently absent in metastases, and exhibits nuclear localization in cancers with either beta-catenin or APC gene mutations. Interestingly, the loss of beta-catenin expression in metastatic gastric cancers may result from hypermethylation of the beta-catenin promoter. 相似文献
100.
PURPOSE: The aim of this study is to report the initial experience with needlescopic surgery (2-mm optics and instrumentation exclusively) for the cryptorchid testicle. METHODS: Ten patients (age 8 months to 37 years) underwent 12 needlescopic procedures: orchiopexy (n = 8), orchiectomy (n = 2), and diagnostic exploration with attempted excision of testicular remnant (n = 2). Two patients underwent bilateral needlescopic orchiopexy. Needlescopic (2 mm) optics and instrumentation were used exclusively in the pediatric patients. RESULTS: All procedures were completed successfully by needlescopic techniques. Mean surgical time was 110 minutes (range, 60 to 180 minutes), and blood loss was 6 mL (range, 0 to 20 mL). There were no intraoperative complications. All procedures were performed on an outpatient basis. In all 8 orchidopexies, the testis was successfully brought to a scrotal position. CONCLUSIONS: Needlescopic techniques allow safe performance of various procedures for a cryptorchid testicle. The cosmetic result is excellent. 相似文献