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991.
The efficacy and tolerability of extended-release felodipine (felodipine-ER) and nifedipine gastrointestinal therapeutic system (nifedipine GITS) were compared in a multicenter, prospective, open-label clinical trial of 277 patients with mild-to-moderate uncomplicated essential hypertension (sitting diastolic blood pressure [SiDBP] > or = 95 and < or = 115 mm Hg). After a 3-week washout period, patients were randomized to receive felodipine-ER (5 mg once daily) or nifedipine GITS (30 mg once daily); during a subsequent 6-week titration phase, the once-daily felodipine-ER dose could be increased to 10 mg and the nifedipine GITS dose to 60 or 90 mg in an attempt to achieve adequate blood pressure response (SiDBP < or = 90 mm Hg, or < 100 mm Hg with a > 10-mm Hg reduction from baseline, as measured 24 hours after dosing [trough]). At the end of titration, the mean daily doses of felodipine-ER and nifedipine GITS were 8 and 50 mg, respectively. Mean changes in sitting systolic blood pressure (SiSBP)/SiDBP were -14/-12 and -16/-13 mm Hg, respectively. All reductions were significant when compared with baseline (P < 0.01), but there were no significant differences between treatment groups. Adequate blood pressure response occurred in 77% of the felodipine-ER group and 80% of the nifedipine GITS group; this difference was not significant. Blood pressure changes were similar among sex and race subgroups. A higher percentage of older patients (> 55 years of age) than younger patients (< or = 55 years of age) reached goal SiDBP with both drugs. Patients with adequate SiDBP response continued receiving their assigned medication for an additional 6-week maintenance period. Reductions in SiDBP and SiSBP from baseline continued to be significant in both treatment groups. No clinically important changes in heart rate were noted. A total of 28 patients (15 in the felodipine-ER group and 13 in the nifedipine GITS group) withdrew from the study because of inadequate blood pressure response. At least one adverse experience occurred in 55% of the felodipine-ER group and 63% of the nifedipine GITS group, prompting withdrawal of 14 patients (10%) and 16 patients (11%), respectively. Headache and edema were the most common adverse experiences. The incidence and pattern of adverse experiences did not differ significantly between treatments. The results of this study demonstrate that once-daily felodipine-ER and nifedipine GITS are similarly highly effective and generally well tolerated in patients with essential hypertension. 相似文献
992.
Telecommunications Information NetworkingArchitecture (TINA) provides an architecture based ondistributed computing technologies to enabletelecommunications networks to support the flexibleintroduction and operation of new advanced services and tomanage both the services and the network in anintegrated fashion. While the service operation andmanagement aspects are well advanced, network management aspects are less well defined. ResourceConfiguration Management (RCM) is one of the mostimportant management areas as it covers, among others,the management of static topology and dynamicconnectivity resources; these are both fundamental to theoperation of TINA services. In this paper we presentfirst an analysis of RCM, which results in introducinga new domain that deals with the configuration of management resources, in addition to network,service and computing resources. We then present ageneric model for configuration management computationalentities; this separates specific task-oriented aspects from generic resource representationsaccessed in a flexible fashion. The genericcomputational interface and relevant methodology forrepresenting and accessing resources are influenced fromOSI/TMN design principles, but make use of the TINAODP-based Distributed Processing Environment (DPE).Based on this generic model, we present an RCM systemarchitecture that deals with network and management resources. Parts of the latter have beenverified through a prototype implementation in thecontext of a real field trial. 相似文献
993.
B Mao A Gorin Z Gu BE Hingerty S Broyde DJ Patel 《Canadian Metallurgical Quarterly》1997,36(47):14479-14490
This paper addresses structural issues related to the capacity of aminofluorene [AF] for frameshift mutations of the -2 type on C8 covalent adduct formation at the G3 site in the d(C-G1-G2-C-G3-C-C) NarI hot spot sequence. This problem has been approached from a combined NMR and relaxation matrix analysis computational structural study of the [AF]dG adduct in the d(C-G-G-C-[AF]G-C-C).d(G-G-C-C-G) sequence context at the 12/10-mer adduct level (designated [AF]dG.del(-2) 12/10-mer). The proton spectra of this system are of exceptional quality and are consistent with the formation of an AF-intercalated conformer with the modified guanine in a syn alignment displaced along with the 5'-flanking cytosine residue into the major groove. The solution structure has been determined by initially incorporating intramolecular and intermolecular proton-proton distances defined by lower and upper bound deduced from NOESY spectra as restraints in molecular mechanics computations in torsion angle space and subsequently refined through restrainted molecular dynamics calculations based on a NOE distance and intensity refinement protocol. Strikingly, the [AF]dG.del(-2) 12/10-mer duplex adopts only one of two potential AF-intercalation alignments for the [AF]dG adduct opposite the -2 deletion site in the NarI sequence context with the extrusion of the dC-[AF]dG step favored completely over extrusion of the [AF]dG-dC step at the lesion site. This polarity establishes that the structural perturbation extends 5' rather than 3' to the [AF]dG lesion site in the adduct duplex. This structure of the [AF]dG adduct opposite a -2 deletion site shows distinct differences with conclusions reported on the alignment of the related acetylaminofluorene [AAF]dG adduct opposite a -2 deletion site in the identical NarI sequence context [Milhe, C., Fuchs, R. P. P., and Lefevre, J. F. (1996) Eur. J. Biochem. 235, 120-127]. In that study, qualitative NMR data without computational analysis were employed to conclude that the extrusion at the lesion site occurs at the [AAF]dG-dC step for the AAF-intercalated conformer of the adduct duplex. The structure of the [AF]dG adduct opposite a -2 deletion site determined in our group provides molecular insights into the architecture of extended slipped mutagenic intermediates involving aromatic amine intercalation and base-displaced syn modified guanines in AF and, by analogy, AAF-induced mutagenesis in the NarI hot spot sequence context. 相似文献
994.
BE Gillesby M Stanostefano W Porter S Safe ZF Wu TR Zacharewski 《Canadian Metallurgical Quarterly》1997,36(20):6080-6089
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related compounds modulate several endocrine systems by altering hormone synthesis, enhancing ligand metabolism, and down-regulating receptor levels/binding activity. Previous studies have demonstrated that TCDD inhibits the 17beta-estradiol (E2)-induction of pS2, a human breast cancer prognostic marker. This inhibition occurs at the gene expression level and is Ah receptor (AhR)-mediated. Analysis of the 5' regulatory region has identified three motifs which resemble dioxin response element (DRE) core sequences. pS2-regulated luciferase deletion constructs identified the DRE-like motif located at -527 to -514 as being required for TCDD-mediated suppression. A point mutation within this core motif (T-518C) abolished the inhibition by TCDD while UV-induced protein-DNA cross-linking and competitive gel retardation assays demonstrated AhR complex binding to this motif. Further study of this region also revealed an adjacent putative AP-1 site, diverging by one base pair from the consensus sequence. Gel retardation assays using TPA-treated MCF-7 cell nuclear extracts showed an induced complex binding to the AP-1-like site. Competition studies and antibody supershifts confirmed that the retarded complex consists of AP-1-like proteins. pS2-regulated luciferase constructs containing mutations specific to the AP-1-like motif greatly diminished the inducibility in response to E2. These results suggest that an interaction between AhR complexes and AP-1-like proteins may be responsible for TCDD-mediated inhibition of E2-induced pS2 expression. 相似文献
995.
Immunization with nonstructural proteins promotes functional recovery of alphavirus-infected neurons
The encephalitic alphaviruses are useful models for understanding virus-neuron interactions. A neurovirulent strain of Sindbis virus (NSV) causes fatal paralysis in mice by infecting motor neurons and inducing apoptosis of these nonrenewable cells. Antibodies to the surface glycoproteins suppress virus replication, but other recovery-promoting components of the immune response have not been recognized. We assessed the effect on the outcome of NSV-induced encephalomyelitis of immunization of mice with nonstructural proteins (nsPs) by using recombinant vaccinia viruses. Mice immunized with vaccinia virus expressing nsPs and challenged with NSV initially developed paralysis similar to unimmunized mice but then recovered neurologic function. Mice preimmunized with vaccinia virus expressing structural proteins were completely protected from paralysis. Mice immunized with vaccinia virus alone showed paralysis with little evidence of recovery. Vaccinia virus expressing only nsP2 was as effective as vaccinia virus expressing all the nsPs. Protection provided by immunity to nsPs was not associated with a reduction in virus replication or with improved antibody responses to structural proteins. Protection could not be passively transferred with nsP immune serum. The depletion of T cells at the time of NSV infection decreased protection. The data show that antiviral immune responses can improve the ability of neurons to survive infection and to recover function without altering virus replication. 相似文献
996.
The degree of diversity in the nature and extent of the physiological deficits which occur in subjects with dysarthria with similar neurological damage is demonstrated through the individual assessment profiles of five subjects with dysarthria following upper motor neurone (UMN) damage. The perceptual profiles of each subject were compiled using perceptual ratings of deviant speech parameters, intelligibility ratings from the Assessment of Intelligibility of Dysarthric Speech (ASSIDS), and perceptual judgements of subsystem function determined from the Frenchay Dysarthria Assessment (FDA). For each individual, the perceptual profile of their speech impairments was compared and contrasted with the objective results of spirometric and kinematic assessments of respiratory function aerodynamic and electroglottographic evaluations of laryngeal function, pressure and strain gauge evaluations of articulatory function, and nasal accelerometric assessments of nasality. The outcomes of the individual perceptual and physiological profiles are discussed with respect to the presence of differential subsystem impairments both within each subject and between subjects with similar underlying pathophysiological deficits. The importance of interpreting the instrumental findings with respect to the interdependency of each of the motor speech subsystems, the limitations of perceptual assessments, and the advantages of utilising both perceptual and physiological analyses in the process of identifying treatment goals is discussed. 相似文献
997.
It has been shown that p53- human colorectal cancer cells arrest after DNA damage in a G2-like state and may then undergo DNA synthesis without intervening mitosis (Waldman et al., Nature 381, 713-716, 1996). To further clarify the role of p53 in the regulation of the G2/M-phase checkpoint, we have studied cells of three closely related human lymphoblastoid cell lines (TK6, WTK1 and TK6E6, an HPV16 E6-transfected TK6 line) with differing p53 status. The cells were irradiated with 1.5-12 Gy gamma rays with or without 2 mM caffeine. There was no evidence of uncoupling of DNA synthesis and mitosis after irradiation in the p53- cell lines, WTK1 and TK6E6, suggesting that this uncoupling may not be a universal phenomenon. The apparent formation of tetraploid cells after irradiation of cells of the p53- WTK1 line was due to the occurrence of a G2-phase block in a pre-existing tetraploid population. These results support the conclusion that control of the G2/M-phase checkpoint after irradiation may differ among different cell types. 相似文献
998.
999.
Effects of print comparative political advertising on political decision-making and participation 总被引:1,自引:0,他引:1
BE Pinkleton 《The Journal of communication》1998,48(4):24-36
An experiment examined intended and unintended effects of print comparative political advertising on political decision-making, voting preferences, and situational election involvement. Results suggested that comparative advertising reduces targeted-candidate voting preferences while avoiding most forms of voter backlash. Voter backlash was evidenced, however, in participants' perceptions that the sponsoring candidate was mean-spirited. Comparative advertising significantly increased participants' situational election involvement. 相似文献
1000.
Earnshaw M.P. Cappuzzo M. Chen E. Gomez L. Griffin A. Laskowski E. Wong-Foy A. 《Electronics letters》2003,39(19):1397-1398
The first demonstration of large-scale integration of AWG filters and thermo-optic switches and attenuators in 2% delta silica-on-silicon waveguides is reported. A compact high performance wavelength selective switch is demonstrated. 相似文献