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91.
92.
A series of cards each containing a two dimensional array of identical Snellen "E's" was used to determine best eccentric visual acuity in patients with macular disease having Snellen visual acuity of 20/70 or worse. Each "full field E" card simultaneously presents the same letter to foveal and parafoveal areas. This test can therefore determine quickly if potentially useful vision is present in any area of the central visual field. In our study of 37 eyes, 70% demonstrated potential visual acuity at least two times better than visual acuity measured by conventional methods, and 20% demonstrated at least a fourfold improvement. This suggests that most patients with macular disease do not spontaneously employ their best remaining area of retina for fixation.  相似文献   
93.
Summary Adenosine has been shown to have negative inotropic, chronotropic and dromotropic effects on the heart. The pharmacological profiles of these effects suggest that they are mediated via Ri (A1) adenosine receptors, but a direct demonstration of these receptors is still missing. In the present study we report direct labelling of these receptors with (-)N6-[125I]-p-hydroxyphenylisopropyladenosine ([125I]HPIA). The radioligand bound in a saturable and reversible manner to a crude membrane preparation, the B max-value was 30.5 fmol/mg protein and the K D-value 1.1 nmol/l. A similar affinity of the ligand was obtained in kinetic and competition experiments. Competition experiments with a variety of adenosine analogues gave a pharmacological profile characteristic of Ri adenosine receptors with high affinities of N6-substituted derivatives and a marked stereospecificity for N6-phenylisopropyladenosine (PIA). Purification of the membrane preparation by density gradient centrifugation resulted in a 30-fold increase in the number of binding sites which was paralleled by a similar increase in the number of binding sites for [3H]ouabain. Guanine nucleotides decreased binding of [125I]HPIA in a dose-dependent manner, but the IC50-values were considerably higher than those reported in other tissues. Finally, binding of [125I]HPIA appeared to be entropy-driven which has been shown to be characteristic of agonist binding to Ri adenosine receptors. These results suggest the presence of Ri adenosine receptors in ventricular myocardium which may be responsible for the mediation of the effects of adenosine and its analogues.Abbreviations [125I]HPIA (-)N6-[125I]-p-hydroxyphenylisopropyladenosine - (-)IHPIA (-)N6-iodo-p-hydroxyphenylisopropyladenosine - (+)/(-)PIA (+)/(-)N6-phenylisopropyladenosine - CHA N6-cyclohexyladenosine - NECA 5-N-ethylcarboxamidoadenosine - App(NH)p 5-adenylylimidodiphosphate - Gpp(NH)p 5-guanylylimidodiphosphate  相似文献   
94.
Migraine is a syndrome and not a nosological entity. It is therefore relatively improbable that a uniform etiology can be defined, and it must be assumed that there are different multifactorial etiological conditions for each individual. It is probable that a therapy concept that is equally valid and promising for all patients can therefore never be developed. On the one hand, there is a variable palette of therapeutic possibilities with a fixed differential indication with regard to the different variants of migraine, and on the other subtle analysis of individual cases is necessary by means of recording the individually relevant somatic, psychological, familial and social parameters. A treatment strategy must then be developed on an individual basis, in which both elements are taken into account. Therapy studies are carried out to investigate various questions and, accordingly, may have different experimental paradigms. The intrinsic action of a therapy method should be compared to the placebo effect on a randomized doubleblind basis. If this preconditions is fulfilled, appraisals of the real chances of success in the practice can be made more accurately on the basis of large-scale open studies comprising a representative cross-section of migraine patients. Further topics for therapy studies should include the analysis of responders and nonresponders and the development of differential indications for certain methods of therapy.  相似文献   
95.
ZK 91296, a partial agonist at benzodiazepine receptors   总被引:2,自引:0,他引:2  
ZK 91296 (ethyl 5-benzyloxy-4-methoxymethyl--carboline-3-carboxylate) is a potent and selective ligand for benzodiazepine (BZ) receptors. Biochemical investigations indicate that ZK 91296 may be a partial agonist at BZ receptors. Such partial agonism may explain to some extent why ZK 91296 needs higher BZ receptor occupancy than diazepam for the same effect against chemical convulsants and for behavioural effects. The lack of sedatiye effects, and the very potent inhibition of reflex epilepsy, spontaneous epilepsy and DMCM-induced seizures suggest, furthermore, that ZK 91296 may possess pharmacological selectivity for a particular type of BZ receptor interaction, perhaps including topographic as well as receptor subtype differentiation.  相似文献   
96.
BackgroundRisk of nephrotoxicity in liver transplant patients on calcineurin inhibitors (CnIs) is a concern. Several controlled trials reported benefit of everolimus (EVR) in minimizing this risk when combined with a reduced CnI dose.BackgroundTo systematically review the efficacy and safety of EVR, alone or with reduced CnI dose, as compared to CnI alone post-liver transplantation.MethodsWe searched MEDLINE, Scopus, and the Cochrane Library for randomized controlled trials comparing EVR- and CnI-based regimens post-liver transplantation. Assessment of studies and data extraction were undertaken independently.ResultsEight studies were selected, describing 769 patients. Cockcroft-Gault GFR was higher at one (P = .05), 3, and 5 years (P = .030) in patients on EVR compared to those receiving CnI therapy. The composite endpoint of efficacy failure was similar between the 2 arms after 1, 3, and 5 years of study. More patients discontinued EVR due to adverse effects in 1 year; however, no difference was noted after 3 or 5 years. A higher rates of proteinuria, peripheral edema, and incisional hernia occurred in patients on EVR.ConclusionsThe analysis confirms noninferiority of EVR and reduced CnI combination. Combination regimen resulted in better renal function compared to standard CnI therapy.  相似文献   
97.
98.
Letermovir is a new antiviral drug approved for the prophylaxis of CMV infection in allogeneic stem cell transplants. The aim of the study was to assess the therapeutic efficacy of letermovir in difficult to treat CMV infections in lung transplant recipients. All lung transplant recipients between March 2018 and August 2020, who have been treated with letermovir for ganciclovir-resistant or refractory CMV infection were included in the study and analysed retrospectively. In total, 28 patients were identified. CMV disease was present in 15 patients (53.6%). In 23 patients (82.1%), rapid response was noticed, and CMV-viral load could be significantly decreased (>1 log10) after a median of 17 [14–27] days and cleared subsequently in all of these patients. Five patients (17.9%) were classified as non-responder. Thereof, development of a mutation of the CMV UL56 terminase (UL-56-Gen: C325Y) conferring letermovir resistance could be observed in three patients (60%). Common side effects were mild and mostly of gastrointestinal nature. Mild adjustments of the immunosuppressive drugs were mandatory upon treatment initiation with letermovir. In addition to other interventions, letermovir was effective in difficult to treat CMV infections in lung transplant recipients. However, in patients with treatment failure mutation conferring letermovir, resistance should be taken into account.  相似文献   
99.
In the present study, interleukin-6(IL-6) and several acute phase proteins were measured in healthy participants (23–87 years of age). A linear correlation between IL-6 and age was established with an increase of 0.016 pg/ml(00.004) per year of life. Whereas CRP remained below 0.5 mg/dl in all participants, an increase with age for fibrinogen and an inverse relation for albumin as well as transferrin were obtained. However, the increase of IL-6 did not correlate with any of these changes. IL-6 associated diseases may therefore occur more often with advancing age, but in healthy participants IL-6 does not explain the changing plasma protein pattern resembling that of an acute phase reaction.  相似文献   
100.
Pro-opiomelanocortin (POMC) mRNA was demonstrated in pituitary adenomas from 16 patients with Cushing's disease and 10 with Nelson's syndrome. The intensity of signal was significantly greater in Nelson's syndrome than in Cushing's disease and there was a trend towards a greater proportion of positive cells. This probably reflects inhibition of POMC gene expression by the high circulating levels of cortisol in Cushing's disease. In the para-adenomatous gland, the intensity of signal was variable in cells showing Crooke's hyaline change, ranging from negative to strongly positive, in keeping with the functional heterogeneity of corticotrophs. In one case, junctional corticotrophs were present and these were more intensely stained than anterior lobe corticotrophs in the same gland. This supports the concept that these cells are subject to different regulatory influences from corticotrophs in the anterior lobe. Whether this is related to differences in embryological origins or to local factors is at present unclear.  相似文献   
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