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A pharmacokinetic study was undertaken to compare the pharmacokinetics of morphine after an intravenous dose with the pharmacokinetics after a sublingual dose administered from an aerosol. Plasma levels of morphine, morphine-3-glucuronide and morphine-6-glucuronide were measured in five normal volunteers after morphine administration by the intravenous route and from a novel sublingual pressurized aerosol formulation. The mean (+/- s.d.) bioavailability of the sublingual aerosol morphine was 19.7 +/- 6.7%. The morphine-3-glucuronide/morphine and the morphine-6-glucuronide/morphine ratios were 5.1 +/- 1.6 and 1.2 +/- 0.4, respectively, for the intravenous route and 28.3 +/- 11.3 and 5.2 +/- 1.4, respectively, for the sublingual route. The combined total areas under the plots of systemic concentration against time (AUC) for the metabolites after the two routes was not significantly different. When compared with published data for oral administration the results demonstrate that the sublingual aerosol morphine might provide an alternative to conventional methods of morphine delivery, and has similar pharmacokinetics to a sublingual morphine tablet. It has no particular pharmacokinetic advantages over oral morphine, except a potential for a faster onset of analgesia. Bioavailability, maximum plasma concentration, Cpmax, and the time at which the maximum plasma concentration is reached, Tmax, are equivalent to those for orally administered morphine.  相似文献   
104.
Human cytomegalovirus (HCMV)-infected cells persist in the presence of anti-HCMV antibody, suggesting that HCMV has evolved mechanisms to evade host immune defenses. Insofar as no virus-encoded complement inhibitors have been identified for HCMV, we hypothesized that HCMV infection may alter the expression of host-encoded cell surface complement inhibitors. Herein, we report that cell surface expression of two complement regulator proteins, CD55 and CD46, which are members of the regulators of complement activation (RCA) gene cluster, increased up to eightfold following infection of fibroblasts or glioblastoma cells with HCMV, but not after infection with HSV-1 or adenovirus. However, the cell surface expression of a third complement regulator, CD59, which is not a member of the RCA gene cluster, was not altered during HCMV infection. Functional studies using purified complement components demonstrated that up-regulation of CD55 suppressed the activity of cell-associated C3 convertases on HCMV-infected cells. Furthermore, increased CD55 expression protected infected cells from complement-mediated lysis, an effect which directly correlated with the length of HCMV infection. Increased expression of host-encoded complement regulator proteins may provide protection of HCMV-infected cells from the host immune response in vivo, through increasing the resistance of infected cells to complement-mediated lysis and decreasing the deposition of C3-derived products on the cell surface.  相似文献   
105.
This study shows that incubation of rat liver mitochondria in the presence of the thiol/ amino reagent 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) is followed by inhibition of both succinate supported respiration and oxidative phosphorylation. Half-maximal inhibition of succinic dehydrogenase activity and succinate oxidation by mitochondria was attained at 55.3 and 60.8 microM DIDS, respectively. DIDS did inhibit the net ATP synthesis and ATP<=>[32P]Pi exchange reaction catalyzed by submitochondrial particles in a dose-dependent manner (Ki = 31.7 microM and Ki = 32.7 microM), respectively. The hydrolytic activities of uncoupled heart submitochondrial particles and purified F1-ATPase were also inhibited 50% by 31.9 and 20.9 microM DIDS, respectively.  相似文献   
106.
The factors controlling the dynamics of HIV-1 transmission from mother to infant are not clearly known. Previous studies have suggested the existence of maternal and placental protective mechanisms that inhibit viral replication in utero. Preliminary studies from our laboratory revealed that supernatant from placental stromal cells protected HIV-1-infected PBMC from virus-induced apoptosis and suppressed virus production. We have attempted to characterize the antiviral activity of this placental factor (PF) and delineate the stages of HIV-1 replication affected. This activity was not due to the presence of any known cytokine reported to have anti-HIV effect. Direct exposure to PF had no suppressive effect on the infectivity of cell-free HIV-1, and envelope-mediated membrane fusion appeared to be unaffected. Western blot analysis of HIV-1 from infected PBMC treated with PF revealed that expression of all viral proteins was reduced proportionately, both intracellularly and in released virions. However, exposure of HIV-1-infected cells to PF resulted in production of virions with 10-100-fold-reduced infectivity. PF-treated virions contained two- to threefold reduced ratios of cyclophilin A:Gag protein as compared with untreated virus. Reduced cyclophilin A content resulting in decreased binding of cyclophilin A to Gag could account, in part, for the observed reduction in infectivity. Our results suggest that placental cells produce an antiviral factor that protects the fetus during gestation and may have therapeutic potential.  相似文献   
107.
We studied the haemodynamic response to cessation of mechanical ventilation and removal of the tracheal tube in 84 patients after coronary artery bypass grafting. Patients were sedated on the ICU with propofol 1-3 mg kg-1 h-1, and randomly allocated to extubation while awake or while still sedated. Systolic and diastolic blood pressures and heart rate increased significantly faster in the awake group as mechanical ventilation was stopped; systolic blood pressure 6.1 (3.0) vs 0.7 (1.8) mm Hg min-1, diastolic blood pressure 2.1 (1.6) vs 0.2 (0.9) mm Hg min-1, heart rate 2.1 (1.7) vs 0.2 (0.5) beats min-2; P < 0.01 in each case. Treatment was required for systolic hypertension during discontinuation of mechanical ventilation in 20 patients (53%) in the awake group and in three patients (7.5%) in the sedated group (P < 0.001). No patient in the sedated group had any new ischaemic ECG changes. Significant new ST segment changes did not occur in the sedated group but were present in five patients in the awake group (P = 0.013), one of whom suffered a perioperative myocardial infarction. Removal of the tracheal tube while patients are still sedated after coronary artery bypass grafting is safe, and reduces the incidences of haemodynamic disturbance and myocardial ischaemia during extubation.  相似文献   
108.
It was studied the condition of mucous layer of intestine in mice model experiments after ionizing radiation. It were found out the differences in reaction of intestine on radiation in mice at the age of 55 and 95 days. In mice at the age of 55 days at the whole stretch of intestine was marked increased secretion of the polymeric glycoproteins, whereas in mice at the age of 95 days such alterations were marked at smaller degree. In both groups mice was marked increased secretion of bicarbonate after radiation, that is possible to count as characteristic compensative mechanism.  相似文献   
109.
Internal customers often are overlooked when business techniques are applied. By applying common external customer satisfaction survey techniques to internal business functions, one hospital identified areas for improvement.  相似文献   
110.
During 1996 and 1997 a panel of European haematologists, oncologists, and neonatologists developed specific paediatric guidelines for the use of colony stimulating factors based on published literature and the clinical experience of these specialists within each of 13 countries. Well established indications for use comprise intervention in patients with life-threatening infection, adjunctive therapy post autologous bone marrow transplantation (BMT), mobilization of peripheral blood progenitor cells for autologous BMT, patients with acquired aplastic anaemia on anti-lymphocyte globulin and cyclosporin regimen, and severe congenital neutropenia. Less clear indications include primary prophylaxis to support dose intensification in children with high risk/advanced malignancies, secondary prophylaxis to prevent neutropenia in patients with a history of severe neutropenia, support therapy in cases of poor marrow function following BMT and for deteriorating marrow function following successful BMT, in neonatal sepsis and non infectious neonatal neutropenia, in drug induced neutropenia and in HIV-positive patients. Treatment is generally well tolerated and granulocyte colony stimulating factor appears better tolerated than granulocyte and macrophage colony stimulating factor. Economically colony stimulating factors have not been shown to induce excessive costs for a given patient. CONCLUSION: In general the adult guidelines are applicable to children but additional considerations (aggressive or very progressive childhood neoplasms, specific indications, neonatal use, congenital disorders) must be taken into account.  相似文献   
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