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51.
Crossed radioimmunoelectrophoresis (CRIE) was used to study the presence of serum IgE against antigenic components of cow milk in 21 selected milk-allergic patients. The amount of each IgE specificity was estimated by a scoring system. The milk-allergic children had mainly IgE against alpha-lactalbumin, beta-lactoglobulin, albumin and immunoglobulin, the four major proteins of bovine whey, as well as IgE against three casein components. A serum pool from 1000 normal adults had IgE against the same whey protein, but in smaller amounts, and no IgE against the casein components. Eight cow milk-based formulae, commonly used for infant feeding, and goat milk were studied by the same method. It was found that six of the milk substitutes did not differ significantly from cow milk in antibody binding, but the two hydrolysed casein products, Nutramigen and Pregestimil, consisted of such small molecules that the rabbit antisera could not precipitate the hydrolysed proteins in the gels on the CRIE plates. It was therefore not possible to study their IgE binding, if any, by this method. 相似文献
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53.
B Schwartz L H Harrison J S Motter R N Motter A W Hightower C V Broome 《American journal of ophthalmology》1989,107(4):341-347
In 1986, an outbreak of Moraxella follicular conjunctivitis occurred in girls attending a Navajo boarding school in New Mexico. We diagnosed 19 cases of culture-proven, and 21 of clinical conjunctivitis based on isolation of Moraxella from conjunctival cultures and the occurrence of symptoms significantly associated with positive culture. Sharing eye makeup was significantly associated with Moraxella-positive conjunctivitis (odds ratio [OR] = 7.2, P = .004) and showed a trend toward significance in those with clinical conjunctivitis (OR = 2.9, P = .09). Eyeliner and eye shadow were implicated (OR = 4.1, P less than .05). We cultured samples of 13 students' makeup; one third of the eyeliners were positive for Moraxella. Nasal carriage of Moraxella was found in 35 (44%) of the 79 female boarders and in 20 (21%) of 97 Navajo patients at two nearby clinics. In a prospective evaluation of the effect of patient education and rifampin therapy on the occurrence of conjunctivitis during an 11-month follow-up period, both types of intervention were successful in significantly reducing the rate of conjunctivitis when compared with that in a control group. 相似文献
54.
55.
Physician motivations for nonscientific drug prescribing 总被引:8,自引:0,他引:8
Although there is increasing concern about inappropriate physician prescribing and how to devise programs to improve drug therapy decisions, little research has been published documenting the reasons for such misprescribing. We analyzed the motivations reported by 141 physicians who were part of a large multi-state randomized controlled trial of 'academic detailing.' The physicians were identified from state Medicaid prescribing records as moderate to high prescribers of cerebral or peripheral vasodilators, propoxyphene, or cephalexin, and were visited by clinical pharmacists serving as outreach educators in a medical school-based prescribing improvement program. Physicians' motivations for their prescribing patterns were discussed in an informal, interactive manner; all responses were recorded in detail by the pharmacists immediately following each visit. Of the 110 responses elicited, the most common reason offered by physicians for use of these medications was patient demand (51 statements, or 46%). Physicians also frequently attributed their prescribing of these drugs to intentional use of placebo effect (24%). An equally common reason was prescribers' assertion that their own clinical experience indicated that these drugs were actually therapies of choice in the conditions presented (26%), despite evidence from the research literature that this was not the case. Such indications included the use of the 'vasodilators' for senile dementia or peripheral vascular disease, cephalexin for viral upper respiratory infections, and propoxyphene instead of acetaminophen or aspirin for mild pain. Greater attention must be paid to physicians' attitudes and motivations concerning suboptimal prescribing if programs are to succeed in replacing these practices with more rational clinical decision-making. 相似文献
56.
57.
D A Schwartz 《Chest》1989,95(6):1338-1339
A 34-year-old man with chronic myelogenous leukemia developed hemoptysis, pain in the left side of the chest, and a systolic heart murmur eight weeks following an allogeneic bone marrow transplant. His clinical status deteriorated, and he died ten weeks after transplantation. Autopsy revealed unsuspected disseminated aspergillosis, including the unusual finding of Aspergillus pancarditis and pericarditis. Cardiac aspergillosis is a uniformly lethal disease in immunocompromised persons and must be aggressively diagnosed following early symptoms. 相似文献
58.
Effect of calcium antagonist drugs on calcium currents in mammalian skeletal muscle fibers 总被引:5,自引:0,他引:5
K B Walsh S H Bryant A Schwartz 《The Journal of pharmacology and experimental therapeutics》1986,236(2):403-407
The calcium channel-inhibiting drugs diltiazem, verapamil and nitrendipine represent three general classes of organic calcium antagonists. In the present study, the effect of these drugs on calcium currents (ICa++) in rabbit sternomastoid muscle fibers was examined. ICa++ were recorded at room temperature using a vaseline gap voltage clamp. ICa++ measured had similar kinetics to those reported in rat skeletal muscle, were partially blocked by 0.5 mM CdCI2 and could be reduced by substitution of Mg++ for Ca++. Diltiazem reversibly blocked ICa++ in a concentration-dependent manner with the 50% inhibitory concentration (IC50) being 63 microM. Verapamil was slightly more potent with approximately 50% block of ICa++ occurring at 10 microM. In contrast, nitrendipine at concentrations from 1 to 10 microM had no blocking action on ICa++, even after 20 min of exposure. Thus, although Ca++ channels in mammalian skeletal muscle fibers are readily blocked by cadmium, diltiazem and verapamil, these channels appear to be insensitive to the dihydropyridine compound nitrendipine. 相似文献
59.
Microsporidia are obligate intracellular spore-forming protozoal parasites belonging to the phylum Microspora. Their host range is extensive, including most invertebrates and all classes of vertebrates. More than 100 microsporidial genera and almost 1,000 species have now been identified. Five genera (Enterocytozoon spp., Encephalitozoon spp., Septata spp., Pleistophora sp., and Nosema spp.) and unclassified microsporidia (referred to by the collective term Microsporidium) have been associated with human disease, which appears to manifest primarily in immunocompromised persons. The clinical manifestations of microsporidiosis are diverse and include intestinal, pulmonary, ocular, muscular, and renal disease. Among persons not infected with human immunodeficiency virus, ten cases of microsporidiosis have been documented. In human immunodeficiency virus-infected patients, on the other hand, over 400 cases of microsporidiosis have been identified, the majority attributed to Enterocytozoon bieneusi, an important cause of chronic diarrhea and wasting. Diagnosis of microsporidiosis currently depends on morphological demonstration of the organisms themselves. Initial detection of microsporidia by light microscopic examination of tissue sections and of more readily obtainable specimens such as stool, duodenal aspirates, urine, sputum, nasal discharge, bronchoalveolar lavage fluid, and conjunctival smears is now becoming routine practice. Definitive species identification is made by using the specific fluorescein-tagged antibody (immunofluorescence) technique or electron microscopy. Treatment options are limited, but symptomatic improvement of Enterocytozoon bieneusi infection may be achieved with the anthelmintic-antiprotozoal drug albendazole. Preliminary observations suggest that Septata intestinalis and Encephalitozoon infections may be cured with albendazole. Progress is being made with respect to in vitro propagation of microsporidia, which is crucial for developing antimicrosporidial drugs. Furthermore, molecular techniques are being developed for diagnostic purposes, taxonomic classification, and analysis of phylogenetic relationships of microsporidia. 相似文献
60.