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91.
A small proteoglycan that contains only a single dermatan sulfate chain is the main proteoglycan synthesized by skin fibroblasts. Fibroblasts from a patient with progeroidal appearance and symptoms of the Ehlers-Danlos syndrome have a reduced ability of converting the core protein of this proteoglycan into a mature glycosaminoglycan chain-bearing species. This abnormality is the consequence of a deficiency in galactosyltransferase I (xylosylprotein 4-beta-galactosyltransferase; EC 2.4.1.133), which catalyzes the second glycosyl transfer reaction in the assembly of the dermatan sulfate chain. The glycosaminoglycan-free core protein secreted by the patient's fibroblasts bears an unsubstituted xylose residue. The mutant enzyme is abnormally thermolabile. Preincubation of fibroblasts at 41 degrees C leads to a further reduction in the production of mature proteoglycan and affects the capacity for glycosaminoglycan synthesis on p-nitrophenyl beta-D-xyloside more strongly in the mutant than in control cells.  相似文献   
92.
Monoclonal antibodies against glycophorins and other glycoproteins   总被引:1,自引:0,他引:1  
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93.
The combined activity of fosfomycin with rifampin, pefloxacin and imipenem was investigated, by the checkerboard method performed in liquid medium, against 50 clinical isolates of staphylococci (25 Staphylococcus aureus and 25 coagulase-negative staphylococci). The combination of fosfomycin plus rifampin had an additive bacteriostatic effect and an antagonistic bactericidal effect. Fosfomycin combined with pefloxacin was found to be additive or moderately synergistic. Fosfomycin in combination with imipenem was generally highly synergistic, especially against meticillin-resistant strains; however the bactericidal effect was occasionally antagonistic.  相似文献   
94.
95.
M J Southcott  M J Tanner  D J Anstee 《Blood》1999,93(12):4425-4435
Phenotypic analysis of hematopoietic stem and progenitor cells has been an invaluable tool in defining the biology of stem cell populations. We use here flow cytometry to examine the expression of human erythroid-specific surface markers during the maturation of early committed erythroid cells derived from cord blood in vitro. The temporal order of the expression of erythroid specific markers was as follows: Kell glycoprotein (gp), Rh gp, Landsteiner Wiener (LW) gp, glycophorin A (GPA), Band 3, Lutheran (Lu) gp, and Duffy (Fy) gp. The time at which some of these markers appeared suggests possible roles for some of these erythroid-specific polypeptides during the differentiation of these committed progenitors. The early appearance of Kell gp raises the possibility that it may have an important role in the early stages of hematopoiesis or cell lineage determination. Kell gp may also be a useful marker for the diagnosis of erythroleukemia. The late expression of Lu gp suggests it may be involved in the migration of erythroid precursors from the marrow. Fy gp is also expressed late consistent with a role as a scavenger receptor for cytokines in the bone marrow and circulation. Rh c antigen appeared before Rh D antigen, and it is suggested that this may reflect a reorganization of the developing erythroid cell membrane involving the Rh polypeptides and other components, including GPA and Band 3.  相似文献   
96.
97.
With Cyclosporin, a recently developed immunosuppressant drug, the authors treated eight patients with noninfectious chronic uveitis: intermediate uveitis (4), Behcet's disease (2), chorioiditis (1), and anterior uveitis (1). Therapy had to be discontinued in six patients who responded poorly or manifested severe side effects. In four cases the Cyclosporin concentration in the aqueous humor was determined. In spite of a concentration of about 900 ng/ml there was a deterioration in two cases with intermediate uveitis and Behcet's disease. Only one of the eight patients with intermediate uveitis responded well without any recurrence.  相似文献   
98.
Fluvoxamine, a selective serotonin reuptake inhibitor, was compared with lorazepam in a multicentre double-blind, parallel group study in 112 general practice patients with mixed anxiety and depression. For inclusion, patients were required to have minimum baseline scores of 21 on the Montgomery-Asberg Depression Rating Scale (MADRS) and 11 on the Clinical Anxiety Scale (CAS). Treatment was for 6 weeks. There were no significant differences between treatments at any point except in an elderly subgroup in whom anxiety improved more rapidly with lorazepam. There were significant improvements in MADRS, CAS and global ratings compared with baseline at all subsequent assessments. Improvement continued during the whole treatment period. Lorazepam produced more sedation, whilst fluvoxamine produced significantly more nausea and vomiting; this was usually early in onset and, if tolerated, resolved during the course of the study. As it is now widely recognized that benzodiazepines should only be given in short courses of 2-4 weeks, the continued improvement up to 6 weeks has implications regarding choice of treatment.  相似文献   
99.
Total nasal reconstruction is a challenging surgical procedure which usually involves a free flap, forehead flap, and cartilage grafts. In certain failure situations where patients do not accept the idea of anaplastology, possibilities become very limited. We report the case of a patient who underwent several reconstruction steps with multiple failures including free and local flaps and cartilage harvests which showed recurrent episodes of necrosis and infection leading to melting and collapse of reconstructed structures. Furthermore, the patient did not want any anaplastological rehabilitation. We proposed to the patient an innovative method that consists to print a three‐dimensional custom‐made porous titanium prosthesis, based on the original shape of his nose, to replace the cartilage support. This implant was first inserted in a thoracodorsal artery perforator flap for primary integration before the free transfer of the complete structure, two months later. The free transfer was successful without any complication. A stable reconstruction and satisfying result was obtained. The patient did not want additional surgical improvement 24 months post‐operatively, and resumed his professional activities. The possibility of using three‐dimensional custom titanium prostheses to replace the bone and cartilage support seems to be an interesting alternative for patients in the failure situation of nasal reconstruction.  相似文献   
100.
A murine monoclonal antibody of specificity anti-Lub was produced. Immunoblotting of the electrophoretically separated components of membranes from Lu(b+) red cells with the monoclonal antibody identified two glycoproteins of relative molecular mass 85 and 78 kd, respectively. The expression of Lub antigenic activity on these glycoprotein components was shown to be dependent on the presence of one or more N-glycosidically linked oligosaccharides and on the presence of disulphide bonding.  相似文献   
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