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41.
42.
We report the case of a 77-year-old man admitted nine days after being commenced on azathioprine with symptoms initially thought to be secondary to sepsis but in fact due to azathioprine hypersensitivity. He developed histologically proven cutaneous leucocytoclastic vasculitis following the re-introduction of azathioprine. We review the literature concerning adverse reactions to azathioprine and the problems of making the diagnosis as well as highlighting azathioprine as a novel cause of leucocytoclastic vasculitis.  相似文献   
43.
Ninety-two patients with Dukes' class C colonic carcinoma, divided equally into those who survived 5 years or more and those surviving less than 5 years after resection for cure, underwent evaluation of multiple histopathologic characteristics of the primary tumor and the uninvolved regional lymph nodes. These characteristics were analyzed by the chi-square test for correlation with survival. A statistically significant correlation (P less than 0.05) in the group who survived 5 years or more was observed for Broders' grades 1 and 2, tumor not involving serosa, and a pushing tumor margin. Of the 14 patients who had a pushing tumor margin and tumor not involving serosa, 12 (86%) survived 5 years or more. Seven patients had an infiltrating tumor margin and peritumor venous invasion, and of this group, only one (14%) survived 5 years or more. Histopathologic characteristics of host immune reaction at the tumor or in the uninvolved regional lymph nodes did not correlate with survival.  相似文献   
44.
The prevalence of coronary artery disease (CAD) and peripheral artery disease (PAD) was studied in 280 (203 males, 77 females) patients with different types of primary hyperlipoproteinemia. In primary hyperbetalipoproteinemia the prevalence of CAD (45% for Type IIa and 47% for Type IIb) is significatly higher than that in the other types of hyperlipoproteinemia (38% for Type IV and 17% for Type V). On the other hand, PAD prevalence is much higher in hypertriglyceridemia (21% in Type IIb and 20% in Type V) than in hypercholesterolemia alone (9% in Type IIa). These results suggest ths atherosclerotic complications are concerned. Moreover, the high frequency of PAD found in hypertriglyceridemia can be related to the high occurrence of diabetes in these patients. The effects of other major risk factors of atherosclerosis (smoking and hypertension) were also evaluated. Our results indicate that the association of hypercholestolemia and hypertension is more dangerous than the co-occurence of hypercholesterolemia and smoking.  相似文献   
45.
The enzyme ornithine decarboxylase (L-Ornithine carboxy-lyase, EC 4.1.1.17), has been partially purified from the livers of mice subjected to partial hepatectomy (6-8 h previously). Mouse liver ornithine decarboxylase requires pyridoxal phosphate, and dithiothreitol for maximal activity. The enzyme has a pH optimum of 7.3, it is inhibited in the presence of 0.3 M phosphate, glycine, Tricine and Tris. It shows no dependence on metal ions and is inhibited by high salt concentrations, particularly ammonium salts. The kinetics of the enzyme have been studied with putrescine (and analogs), spermidine and spermine, in the presence of both high and low levels of pyridoxal phosphate. High concentrations of pyridoxal phosphate inhibit the enzyme. The enzyme is also inhibited by low concentrations of putrescine (1 mM). As the concentration of putrescine increased to 10 mM, non-competitive inhibition was observed, this could be reversed by addition of higher levels of pyridoxal phosphate. Spermidine and spermine inhibit (noncompetitively) only at high concentrations (10 mM). Ornithine inhibits at high concentrations (2 mM). Spectral studies have shown that the observed kinetics of competitive inhibition at low concentrations of polyamine changing to noncompetitive inhibition at high polyamine concentrations are due to competition between enzyme and substrate (or inhibitor) for free (non-enzyme bound) pyridoxal phosphate. Noncompetitive inhibition arises through the formation of transient Schiff base complexes between amines and free pyridoxal phosphate. It also appears that the binding of substrate to the active site takes place through Schiff base formation with enzyme bound pyridoxal phosphate.  相似文献   
46.
Eighty-four geriatirc ward patients were randomly assigned to groups targeted for outplacement planning or inpatient care. During the following year, half of the former were placed in community settings while nearly all of the latter remained in the hospital. Neither the physical health, level of self-care, or psychiatric condition ratings of the two groups changed differentially over that time. However, the mean Morale Inventory score of the outplacement sample improved while that of the in-patient group remained static. Additional analyses were run between three groups - outplacement planning subjects who were released, those who were not released, and inpatient planning men who were not released. These results confirmed those of the first analyses; the only significant difference appeared on the Morale Inventory, the patients who left showing more improvement than the other two groups. The results argue for an increased emphasis on outplacement programs among geriatric patients.  相似文献   
47.
48.
Tenascin-R is a multidomain molecule of the extracellular matrix in the CNS with neurite outgrowth inhibitory functions. Despite the fact that in amphibians spontaneous axonal regeneration of the optic nerve occurs, we show here that the molecule appears concomitantly with myelination during metamorphosis and is present in the adult optic nerve of the salamander Pleurodeles waltl by immunoblots and immunohistochemistry. In vitro, adult retinal ganglion cell axons were not able to grow from retinal explants on a tenascin-R substrate or to cross a sharp substrate border of tenascin-R in the presence of laminin, indicating that tenascin-R inhibits regrowth of retinal ganglion cell axons. After an optic nerve crush, immunoreactivity for tenascin-R was reduced to undetectable levels within 8 d. Immunoreactivity for the myelin-associated glycoprotein (MAG) was also diminished by that time. Myelin was removed by phagocytosing cells at 8-14 d after the lesion, as demonstrated by electron microscopy. Tenascin-R immunoreactivity was again detectable at 6 months after the lesion, correlated with remyelination as indicated by MAG immunohistochemistry. Regenerating axons began to repopulate the distal lesioned nerve at 9 d after a crush and grew in close contact with putative astrocytic processes in the periphery of the nerve, close to the pia, as demonstrated by anterograde tracing. Thus, the onset of axonal regrowth over the lesion site was correlated with the removal of inhibitory molecules in the optic nerve, which may be necessary for successful axonal regeneration in the CNS of amphibians.  相似文献   
49.
Middle ear effusion has been considered the most common cause of vestibular disturbance in children. However, there have been only a few studies on vestibular disturbance in children with otitis media with effusion. We studied the vestibular systems of 30 children with otitis media with effusion aged 8 to 13 years and compared the results with 15 age- and sex-matched controls. A questionnaire relating to vestibular disturbance was given to patients and their parents. Spontaneous nystagmus and positional nystagmus were recorded by electronystagmography as diagnostic tests of the vestibular system. Romberg's and past-pointing tests were performed on children with otitis media with effusion and controls. After vestibular tests were completed, myringotomy was performed, and a ventilation tube was inserted. The questionnaire and the vestibular tests were repeated after the operation and during the first month after surgery. Our study showed that there was a history of vestibular disturbance in 33% of children with otitis media with effusion. Electronystagmography and Romberg's test findings demonstrated that 33% of the children had vestibular dysfunction (p < 0.05). After myringotomy with ventilation tube insertion, vestibular test results returned to normal, and symptoms related to vestibular disturbance improved. These findings confirm the assumption that middle ear effusion may affect the vestibular system, which can be resolved after myringotomy with ventilation tube insertion.  相似文献   
50.
Ten diabetic renal transplant patients had porcine fetal islet-like cell clusters (ICC) injected intraportally or placed under the kidney capsule. In some patients, temporary graft survival was achieved, as evidenced by the urinary excretion of small amounts of porcine C-peptide (4 patients) and the identification of some intact insulin-staining cells in a biopsy specimen (1 patient). Glucose metabolism remained unaffected. To improve the results, better islets and better immunosuppressive protocols are required. We found that, while fetal porcine ICC produced insulin only after several weeks, adult islets gave immediate insulin production. The search for an optimal immunosuppression was conducted in the pig-to-rat islet transplant model. A clear inhibitory effect on the xenograft rejection was observed when using some of the new drugs. The best results were achieved with a triple drug regimen consisting of cyclosporine, mycophenolate mofetil and leflunomide.  相似文献   
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