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81.
Abstract The outcome of OLT for HBV-related liver disease is dependent on the prevention of allograft re-infection. Over the past decade, major advances have been made in the management of HBV transplant candidates. The advent of long-term hepatitis B immune globulin (HBIG) administration as a prophylaxis against HBV recurrence, and the introduction of new antiviral agents against HBV infection, such as lamivudine (LAM), were a major breakthrough in the management of these patients. Results of OLT for HBV infection are similar to those achieved with other indications. Pre-OLT antiviral treatment such as LAM can suppress HBV replication before OLT and thus decrease the risk of re-infection of the graft. Combination prophylaxis with LAM and HBIG after transplantation highly effectively reduces the rate of HBV re-infection, even in HBV replicative cirrhotic, patients. The optimal HBIG protocol in the LAM era is yet to be defined: dosing of HBIG, routes of administration, and possibility of stopping HBIG. Several antiviral drugs have been developed for the management of HBV infection on the graft, so outcome is currently good.  相似文献   
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84.
Effects of rufloxacin in Salmonella typhimurium infection in mice.   总被引:1,自引:0,他引:1  
This study was undertaken to investigate the efficacy of rufloxacin, a new quinolone which is interesting due to its pharmacokinetics characterized by a long plasma half-life, in the treatment of systemic salmonella infections in the mouse typhoid model. Innately susceptible BALB/c and resistant CBA mice were used to investigate the efficacy of rufloxacin in controlling systemic salmonella infections when given for brief or prolonged periods. The present study shows that rufloxacin is not only very effective on both mouse strains, but can completely eradicate the salmonellae from livers and spleens when given early in the infection of CBA resistant mice.  相似文献   
85.
The Harderian gland (hg) is a gland which occupies a large portion of the orbital cavity. In many species, a sexual dimorphism occurs, which suggests a gonadal steroid control of the hg. The present study examines, in primary cultures of hamster hg cells, the regulation of the androgen receptor mRNA (AR mRNA) expression. In dose–response experiments measuring the expression of AR mRNA, testosterone (T) (10−12M) induced a 1-fold increase of AR mRNA compared with unexposed cells, and this effect reached its zenith (6.2-fold) when cells were exposed to 10−8MT. In other experiments, cells were exposed or not to different drugs [T, T + flutamide (F), F, T + cycloheximide (Cy), Cy] for different times (up to 96 hr). These experiments showed a time-dependent increase of AR mRNA in the cells exposed to T, while in the cells exposed to F, T+F, T+Cy, Cy, and control (unexposed), a time-dependent decrease of AR mRNA was observed. The size of the hamster AR mRNA in thesein vitroexperiments was similar to that observed in other mammals (9.5 kb). It is concluded that primary cultures of hamster hg cells are a valuable model for studying hg cell activity and that in this system T autoinduces its own receptor.  相似文献   
86.
The aim of the present study was to investigate the existence of alterations of the blood-brain barrier (BBB) permeability in rats injected with centrally acting drugs, by calculating a unidirectional blood-to-brain transfer constant (Ki) for the circulating tracer [14C]-alpha-aminoisobutyric acid. The intraperitoneal (i.p.) injection of the dopaminergic antagonist haloperidol (1 mg kg-1) did not modify the regional BBB permeability. When the cholinomimetic agent arecoline hydrobromide (6.25 mg kg-1) was injected i.p. into methylatropine-pretreated rats, it induced a significant decrease of Ki values within the frontal cortex, parietal cortex, striatum and brain-stem. Our findings emphasize two concepts: (1) centrally acting drugs, such as arecoline, can induce changes in the BBB permeability, through several mechanisms; (2) there is no predictable correlation of drug stimulation of specific brain neuronal pathways and changes in the permeability of the BBB.  相似文献   
87.
Human immunodeficiency virus (HIV)-associated progressive multifocal leukoencephalopathy (PML) remains a relevant clinical problem even in the era of highly active antiretroviral therapy (HAART). Aims of the study were to analyze clinical and treatment-related features and the survival probability of PML patients observed within the Italian Registry Investigative Neuro AIDS (IRINA) during a 29-month period of HAART. Intravenous drug use, the presence of focal signs, and the involvement of white matter at neuroradiology increased the risk of having PML. A reduced probability of PML was observed when meningeal signs were reported. Patients starting HAART at PML diagnosis and previously naïve for antiretrovirals showed significantly higher 1-year probability of survival (.58), compared to those continuing HAART (.24), or never receiving HAART (.00). Higher CD4 cell count were associated with a higher survival probability (.45). At multivariate analysis, a younger age, higher CD4, starting HAART at PML diagnosis, the absence of previous acquired immunodeficiency syndrome (AIDS)-defining events, and the absence of a severe neurologic impairment were all associated with a reduced hazard of death. The use of cidofovir showed a trend towards a reduced risk of death.  相似文献   
88.
The purpose of this study was to estimate the radiation doses to nursing staff, other patients, accompanying persons and family members deriving from patients undergoing 111In-DTPA-d-Phe-1-octreotide (111In-OCT) scintigraphy. Dose rates were measured from 16 patients who had received an intravenous injection of 140±40 MBq 111In-OCT. The measurements were performed at three different distances (0.5, 1 and 2 m) at 10–20 min, 5–7 h and 24 h (and in some cases, up to 48 h) after administration of 111In-OCT. The effective half-lives of the biexponential decrease of the dose rates were estimated to be 2.94±0.27 h (T 1) and 65.17±0.58 h (T 2). The calculated maximum dose to other persons in the waiting area was 27.2 μSv, to family members 61.5 μSv, to nursing staff in a ward 24.1 μSv and to neighbouring patients in the ward 69.5 μSv. Our results clearly demonstrate that the calculated maximum radiation exposure to accompanying persons, personnel, family members and other patients is well below the maximum annual dose limit for non-professionally exposed persons. Received 20 May and in revised form 9 July 1997  相似文献   
89.
The authors report on 14 patients with epidermoid carcinoma of the glottic region, classified T1, T2 and T3, operated upon by a hemilaryngectomy (9 cases) with reconstruction using a Plathysma myocutaneous flap. The oncological results over a follow-up period of 1 to 6 years and the functional results are analyzed. The authors conclude that this method does not compromise the carcinological result and provides a good functional result with low ratings for complications, with in addition an adequate support for the organ, favouring increased resections.  相似文献   
90.
Summary Conventional imaging with computed tomography (CT) and magnetic resonance imaging (MRI) may show abnormalities in central nervous system Behcet's syndrome but is normal in some cases. Recently in two cases positron emission tomography has shown abnormalities in blood flow and glucose metabolism far more extensive than the abnormalities seen on CT and MRI scans in the same patients. We report a patient with neuro-Behcet's syndrome presenting with headache and personality change in whom CT and MRI brain imaging was normal, but regional cerebral blood flow imaging using single photon emission tomography with the tracer HMPAO showed extensive perfusion deficits which partially reversed after 3 months of prednisolone therapy. This technique may aid the diagnosis of cerebral involvement in Behcet's syndrome, although the cause and incidence of the perfusion deficits need further evaluation.  相似文献   
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