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A number of novel pyridazinomorphinans have been synthesized by the inverse electron demand Diels-Alder reaction of various 3,6-disubstituted 1,2,4,5-tetrazines with enamines derived from dihydrocodeinone and with codeinone. Reduction of some of the pyridazinomorphinans did not furnish the expected pyrroloepoxymorphinans; in all cases investigated reductive cleavage of the epoxybridge was observed to yield dihydropyridazino- or pyrrolomorphinans. The structures of all new compounds were assigned by the spectral data, that of the cycloadduct of codeinone was additionally verified by X-ray crystallography. Compounds 5a, 8, 11a , and 16 have been evaluated for their affinity at μ and κ opioid receptors in radioligand binding assays. Their ability to inhibit [3H]DAMGO binding at μ and [3H]U 69.593 binding at κ receptors, respectively as compared to codeine has been found to be lower.  相似文献   
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Outpatient anterior chamber lens implantation   总被引:1,自引:0,他引:1  
100 outpatient and 143 inpatient intracapsular cataract extractions with anterior chamber lens implantation were examined 6 months post-operatively. 74 (74%) in the former and 107 (75%) in the latter achieved visual acuity greater than or equal to 0.5. Excluding non-surgical pathology, 93% in the outpatient group and 98% in the inpatient group had a visual acuity greater than or equal to 0.5 (P = 0.12). There were no significant differences in post-operative complications except for the incidence of cystoid macular edema. Six (6%) of the outpatient and 1 (0.7%) of the inpatient procedures had cystoid macular edema that resulted in a visual acuity below 0.5 (P = 0.02).  相似文献   
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The CT-examinations of 15 patients with blow-out fractures of the orbital floor were reviewed. All patients were examined with coronal/semicoronal CT-imaging, and 7 patients also were evaluated with semisagittal projections. Only in one case the semisagittal images gave more information than coronal sections when using the classification of Gilbard et al. (1985) of the inferior rectus muscle/fracture relationship. The anterior and posterior fracture margins were better delineated with semisagittal imaging. Two patients exhibiting positive traction tests with hooked, and not entrapped muscles on CT still had diplopia 5 1/2 and 12 weeks after the trauma.  相似文献   
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Peptides may function as neurotransmitters liberated antidromically by sensory nerve fibres, provoking vascular responses having potential importance in some neurological disorders. Dose-response relaxation curves induced by substance P (SP) and calcitonin gene related peptide (CGRP) have been studied in porcine ophthalmic arteries in vitro. Both peptides induced vasodilation when tested separately (CGRP much greater than SP). Because of the putative interactions between such peptides in this vascular territory, a computerised system was also used for analysing over time the response to a single addition of either 10(-8) M CGRP, 10(-8) M SP or a combination of 10(-8) M SP + 10(-8) M CGRP. SP did not augment the maximum relaxation induced by CGRP alone, but increased significantly the rate of relaxation during the initial phase of the response. The effect induced by the SP+CGRP combination was stronger than the sum of the individual SP and CGRP-induced relaxations during the first 4 min of the response, which suggests a SP-CGRP synergism in this artery.  相似文献   
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During the 11 month period up to 30 September 1987, 37 patients (26 male, 11 female, mean age 27 years) with respiratory symptoms who were human immunodeficiency virus (HIV) positive, were studied prospectively on 40 occasions to determine the cause of any pulmonary complications. HIV was heterosexually transmitted. Predominant symptoms were cough (89%), fever (89%), weight loss (83%), and dyspnoea (60%). Transnasal fibre-optic bronchoscopy (with bronchoalveolar lavage, bronchial brushings and transbronchial lung biopsies) was performed on 35 patients, twice on 3 patients. 'Tru-cut' lung biopsies were obtained from 2 patients who died before bronchoscopy. Pulmonary tuberculosis was the commonest disease, being found in one-third of the patients (12 of 37). Mycobacterium tuberculosis was cultured from 4; the remainder of the plates were contaminated. Pneumocystis carinii was present in 8 patients: as the sole pathogen in 3, with Streptococcus pneumoniae in 4, Staphylococcus aureus in 2, and one also had tuberculous lymphadenitis. Endobronchial Kaposi's sarcoma was seen in 6 of 7 patients with skin nodules. Bacterial pathogens isolated included Staph. aureus (5), S. pneumoniae (5), Klebsiella pneumoniae (2), Haemophilus influenzae (2), H. parainfluenzae (1) and Pseudomonas aeruginosa (1). Invading Aspergillus fumigatus was diagnosed by lung biopsy in one. No diagnosis was reached for 8 patients. It is concluded that in Central Africa pulmonary complications in AIDS patients are similar to those in Europe and North America but the incidence of different pathogens depends on the prevalence of pathogens in the community. M. tuberculosis is probably the commonest pathogen. This study has confirmed that P. carinii pneumonia does occur, but occurs less frequently.  相似文献   
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In this study the endocrine function following intraperitoneal hetero- and orthotopic pancreatico-duodenal-splenic allotransplantation (PDS) in hemipancreatectomized, non-immune-suppressed chacma baboons was assessed. Significantly reduced K-values and insulin release together with glucose intolerance during IVGTT were observed in hemipancreatectomized recipients (HPS) without grafts. Orthotopic and heterotopic PDS transplantation improved the glucose intolerance of HPS recipients; orthotopically sited grafts rendering the best curves. Normal glucose tolerance was not achieved. Both orthotopic and heterotopic PDS transplantation rendered suboptimal insulin release during IVGTT; heterotopically draining grafts released significantly more insulin than orthotopic grafts. Hyperglucagonaemia during IVGTT was a constant feature in both groups, heterotopic grafts releasing the most glucagon during stimulation. C-peptide release was significantly lower in orthotopic grafts compared to normal animals or heterotopically drained insulin. It is concluded that glucose tolerance was not directly related to insulin or glucagon release in this study as orthotopic grafts rendered near-normal IVGTT curves in the presence of hypoinsulinaemia, hyperglucagonaemia, and reduced C-peptide values. The hormonal response after PDS transplantation was variable and the advantages of portal vs systemic insulin drainage remain to be defined.  相似文献   
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