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11.
The imino sugar N-butyldeoxynojirimycin (NBDNJ) is a potent inhibitor of the oligosaccharide-trimming enzyme alpha-glucosidase I. Hepatitis B virus (HBV) contains three surface proteins (HBs proteins) of different sizes that are singly or doubly N-glycosylated and are essential for the formation of infectious virus. Therefore, the replication and secretion of HBV in the human hepatoma cell line HepG2 were studied in the presence of NBDNJ. In the stably HBV-transfected HepG 2.2.15 cells and in HBV-infected HepG2 cells, NBDNJ suppressed secretion of HBV particles and caused intracellular retention of HBV DNA. The secretion of subviral particles was less affected. These data suggest that inhibitors of oligosaccharide trimming may be useful for antiviral therapy of hepatitis B and for the study of the intracellular transport of the viral glycoproteins.  相似文献   
12.
PURPOSE: To explore potential indicators of the quality of end-of-life services for cancer patients that could be monitored using existing administrative data. METHODS: Quality indicators were identified and assessed by literature review for proposed indicators, focus groups with cancer patients and family members to assess candidate indicators and generate new ideas, and an expert panel ranking the meaningfulness and importance of each potential indicator using a modified Delphi approach. RESULTS: There were three major concepts of poor quality of end-of-life cancer care that could be examined using currently-available administrative data (such as Medicare claims): institution of new anticancer therapies or continuation of ongoing treatments very near death; a high number of emergency room visits, inpatient hospital admissions, or intensive care unit days near the end of life; and a high proportion of patients never enrolled in hospice, only admitted in the last few days of life, or dying in an acute-care setting. Concepts such as access to psychosocial and other multidisciplinary services and pain and symptom control are important and may eventually be feasible, but they cannot currently be applied in most data systems. Indicators based on limiting the use of treatments with low probability of benefit or indicators based on economic efficiency were not acceptable to patients, family members, or physicians. CONCLUSION: Several promising claims-based quality indicators were identified that, if found to be valid and reliable within data systems, could be useful in identifying health-care systems in need of improving end-of-life services.  相似文献   
13.
Intrastriatal injection of quinolinic acid (QA) in rats provides an animal model that mimics some of the neuropathological and neurochemical alterations observed in the striatum of patients with Huntington's disease (HD). One of the very early neurophysiological signs in HD is a diminution of amplitude of early somatosensory evoked potentials (SEPs) recorded over the parietal cortex. The present study investigated whether the QA model exhibits similar neurophysiological abnormalities. Two weeks after unilateral intrastriatal injection of QA (240 nmol) or of the solvent, early SEPs were recorded with chronically implanted electrodes from the somatosensory cortex or from the ventrobasal nucleus of the thalamus of lightly pentobarbital-anesthetized rats, in response to single-shock electrical stimulation of the contralateral forepaw. Whereas intrastriatal injection of solvent did not influence SEPs, the striatal QA lesion significantly reduced the amplitude of early cortical SEPs by about 40% without affecting the latency. SEPs recorded from the ventrobasal nucleus were unchanged after QA lesion. Histological examination and glial fibrillary acid protein staining after intrastriatal injection of QA revealed no evidence for damage in the somatosensory system. It is concluded that (1) the QA animal model of HD mimics some of the SEP abnormalities of patients, and (2) a striatal lesion modulates somatosensory transmission to the cortex in rats.  相似文献   
14.
15.
The deuterium nuclear spin relaxation times have been measured in tissues taken from rats given 20% deuterium oxide in their drinking water. The spin-lattice and spin-spin relaxation times were measured at 13.7 MHz by the inversion-recovery and Carr-Purcell-Meiboom-Gill FT methods, respectively. The reciprocals of the spin-lattice (T1) relaxation times were found to correlate well with those of protons in similar nondeuteriated tissues at a similar frequency (13.6 MHz) measured in a separate study. A least-squares analysis of the data yields (1/T1)H = (0.991)(1/T1)D - 3.48 for five tissues (standard deviations of 0.097 for the slope and 0.383 for the intercept with a correlation coefficient of 0.986). Implications with respect to relaxation mechanisms are discussed.  相似文献   
16.
Cromolyn sodium, a recently introduced antiasthmatic medication, is known occasionally to produce maculopapular and urticarial rashes, and increased bronchospasm. A patient is reported with a previously unpublished side effect of this medication, i.e., severe nasal congestion.  相似文献   
17.
The serious result of hepatitis B (HBV) virus infection is development of hepatocellular carcinoma (HCC). However, the reason of development of HCC in HBV infected patients is still unclear. Recently, the suppression of cell apoptosis is found to relate with the development of cell carcinogenesis, therefore, the expression of apoptosis inhibitor in the virus related cancer line such as hepatoma cell line HepG2.215 was investigated. There are at least six Human apoptosis inhibitors (IAP) have been identified now. They are cIAP1, cIAP2, XIAP, NAPI, survivin and pIAP. Using gene-assay technology, we have recently compared the expression of IAPs in the HepG2.215 cells that persistently expresses Hepatitis B virus by integrated HBV genome with its parent cell line HepG2. The results suggest that there was obviously increase of cIAP2 and cIAP1 in the HepG2.215 cells versus HepG2 cells. Those observations imply a possibility of long time HBV infection could induce the over-expressing apoptosis inhibitors, furthermore, causing the liver cancer. The high expression of cIAP1 and cIAP2 in HBV expressing cells was confirmed by RT-PCR and Northern blot analysis. However, we did not find the change of NIAP and suvivin in HepG2.215 cells. In contrast, the expression of XIAP was down in the HepG2.215 cells comparing with HepG2 cells. How HBV triggers the over-expression of apoptosis inhibitor is unclear. Transient transfection of HepG2 cells with the plasmids expressing different HBV proteins such as S, M, L, X and core proteins did not give a decisive conclusion. Further study is going on now.  相似文献   
18.
Controlled studies in clinical cancer research   总被引:2,自引:0,他引:2  
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19.
The Bioperl toolkit: Perl modules for the life sciences   总被引:36,自引:4,他引:36  
The Bioperl project is an international open-source collaboration of biologists, bioinformaticians, and computer scientists that has evolved over the past 7 yr into the most comprehensive library of Perl modules available for managing and manipulating life-science information. Bioperl provides an easy-to-use, stable, and consistent programming interface for bioinformatics application programmers. The Bioperl modules have been successfully and repeatedly used to reduce otherwise complex tasks to only a few lines of code. The Bioperl object model has been proven to be flexible enough to support enterprise-level applications such as EnsEMBL, while maintaining an easy learning curve for novice Perl programmers. Bioperl is capable of executing analyses and processing results from programs such as BLAST, ClustalW, or the EMBOSS suite. Interoperation with modules written in Python and Java is supported through the evolving BioCORBA bridge. Bioperl provides access to data stores such as GenBank and SwissProt via a flexible series of sequence input/output modules, and to the emerging common sequence data storage format of the Open Bioinformatics Database Access project. This study describes the overall architecture of the toolkit, the problem domains that it addresses, and gives specific examples of how the toolkit can be used to solve common life-sciences problems. We conclude with a discussion of how the open-source nature of the project has contributed to the development effort.  相似文献   
20.
Autologous bone harvested from the ilium is commonly used as a grafting material in surgical reconstructive and arthrodesis procedures to ensure a satisfactory postoperative outcome. However, operative removal of bone from the iliac crest requires an additional surgical procedure with a distinct set of postoperative complications. We provide a comprehensive literature synthesis of the incidence and severity of complications reported to be associated with this commonly practiced procedure. Most severe complications are rare, but chronic pain at the donor site exceeding three months in duration occurs frequently and can be particularly bothersome to patients. Alternative grafting materials that are safe and effective are sorely needed.  相似文献   
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