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41.
Sera of 86 patients clinically sensitive to foods were tested by passive sensitization of human and/or monkey lung (127 tests) and the radioallergosorbent test (RAST) (72 tests), using whole-food antigens; the results were compared with skin (prick) testing. Results of the prick test correlated with history in 76% of cases; lung sensitization correlated with history in 37% and with prick test in 57%; and RAST correlated with history in 54% and prick test in 72%. It is concluded that a very large percentage of adverse reactions to foods are IgE-mediated. The prick test is of use in diagnosis, particularly when combined with RAST; the lung sensitization test is technically impractical and not a reliable indicator. The best diagnostic method is careful history with food challenge and withdrawal and rechallenge; the latter is safe except in patients with a history of violent reaction.  相似文献   
42.
In a comprehensive study of 80 patients with vasculitis, 4 had concurrent hepatitis B virus (HBV) infection. Polyarteritis nodosa was present in 2 and in the other 2, cutaneous vasculitis, presenting clinically as palpable or Henoch-Schönlein purpura. In one of these patients skin biopsies demonstrated granular deposits of IgM, C3, C4, and the hepatitis B surface antigen (HBsAg) and electron-dense deposits of aggregated 20-nm particles resembling HBsAg in postcapillary venules. Evidence for circulating HBsAg-immune complexes included increased serum C1q binding activity, decreased serum complement, and a cryoprecipitate containing both HBsAg and IgM anti-HBs. Aggregated 20-nm particles resembling intact HBsAg were also seen by negative staining electron microscopy of the serum cryoprecipitate. This patient fulfills all the criteria for a specific immune complex vasculitis caused by his immune response to a chronic HBV infection. These findings emphasize that HBV infection may be associated with small vessel vasculitis as well as polyarteritis nodosa, mixed cryoglobulinemia, and glomerulonephritis. A similar immune response to other viral infections may be expressed as palpable (Henoch-Schönlein) purpura also.  相似文献   
43.
The sister chromatid exchange (SCE) incidence and growth kinetics have been studied by means of an in vitro bromodeoxyuridine (BrdU) chromosome labeling method in the bone marrow cells of 17 acute myeloblastic leukemia (AML) patients with only diploid cells at diagnosis, remission, and relapse of the disease. At diagnosis, the cells tended to exhibit a low SCE frequency as compared to that during remission. An increased SCE frequency was observed after chemotherapy during remission or relapse. At diagnosis and relapse, when leukemic blast cells predominated in the marrow, they were characterized by the predominance of cells that had undergone only one cell cycle after BrdU exposure. In contrast, the marrow cells during remission tended to resemble the control pattern of growth kinetics, with a predominance of cells undergoing second and third cell cycles in the presence of BrdU. These results suggest that the growth rate of leukemic and nonleukemic cells is different, and that chemotherapy can cause an increased SCE frequency in the marrow cells of AML patients irrespective of the state of the disease.  相似文献   
44.
《Immunity》2020,52(4):683-699.e11
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45.
The regulatory role of vitamin D receptor (VDR) gene variants of Bsm I, Apa I, Taq I, and Fok I polymorphisms on vitamin D(3)-modulated macrophage phagocytosis with live Mycobacterium tuberculosis and lymphoproliferative response to M. tuberculosis culture filtrate antigen (CFA) was studied in patients with pulmonary tuberculosis (n = 46) and in normal healthy subjects (NHS) (n = 64). Vitamin D(3) at a concentration of 1 x 10(-7) M enhanced the phagocytic potential of normal subjects who had a phagocytic index of less than 20%. This increase was seen in subjects with the genotypes BB (p = 0.017), AA (p = 0.016), tt (p = 0.034), and FF (p = 0.013) and the extended genotype BBAAtt (p = 0.034). Normal subjects with BBAAtt performed better phagocytosis than individuals with bbaaTT genotype (p = 0.034). Vitamin D(3) at 10(-9), 10(-8), and 10(-7) M concentrations suppressed the lymphoproliferative response to CFA antigen in normal subjects. This decreased lymphocyte response was observed in normal individuals with the genotypes BB (p = 0.0009), tt (p = 0.016), and FF (p = 0.008) and the extended genotype BBAAtt (p = 0.02). Addition of vitamin D(3) had no significant effect on macrophage phagocytosis and lymphoproliferative response to CFA in pulmonary TB patients. This may be due to the unresponsive nature of the cells to the action of vitamin D(3) or the downregulated VDR expression by virtue of the disease, which renders them inactive. The genotypes BB, tt, and the extended genotype BBAAtt may be associated with increased expression of VDR which in turn regulate the action of vitamin D(3) and modulate the immune functions to M. tuberculosis in NHS.  相似文献   
46.
Fluocortin butyl (FCB) is a newly synthesized corticosteroid with a high ratio of topical to systemic activity. FCB was studied in a multi-center, double-blind, placebo-controlled trial of therapy of perennial rhinitis. The study was conducted between January and May 1981. Patients evaluated suffered from either chronic allergic or chronic nonallergic rhinitis or both. A total of 306 patients from 16 investigative centers were evaluated by comparing FCB to placebo. Three separate dosage regimens were employed. Patients received a total daily dose of 2, 4, or 8 mg. FCB was found to be an effective therapeutic agent. It reduced symptoms of nasal congestion, rhinorrhea, postnasal drainage, and sneezing. It also markedly reduced the use of concomitant medications (chlorpheniramine maleate and/or pseudoephedrine). Relief of symptoms was noted as early as the first week of therapy, and the degree of improvement increased progressively during the study. There was little difference between the relief produced by the 4 mg and 8 mg regimens. Both of these were superior to the 2 mg regimen. The drug was well tolerated; no significant side effects were noted.  相似文献   
47.
Bronchodilator efficacy of metaproterenol sulfate aerosol therapy delivered either by canister or jet nebulizer was compared in 25 patients, 13 with severe asthma and 12 with COPD. Treatment was carried out in double-blind crossover fashion on 2 days and consisted of either metaproterenol sulfate solution 15 mg in 2.3 ml administered from a jet nebulizer or three puffs of metered-dose metaproterenol sulfate (total 1.95 mg) inhaled sequentially. FVC and FEV1 were monitored before and after therapy for 2 hr. In 13 asthmatic patients, FEV1 increased from a baseline mean of 0.83 L to 1.57 L at 2 hr after jet nebulizer therapy and increased from 0.84 L to 1.52 L after canister therapy. In 12 patients with COPD, FEV1 increased from 0.58 L to 0.78 L after jet nebulizer therapy and from 0.57 L to 0.76 L after canister therapy. FVC also increased similarly after each form of therapy. The two types of aerosol therapy were equally effective and were without side effects. Canister therapy has the advantage over jet nebulizer therapy by being convenient and cheaper.  相似文献   
48.
Distinguishing characteristics of a new neuroblastoma cell line   总被引:3,自引:0,他引:3  
The characteristics of a new neuroblastoma cell line (MC-NB-1) established from the bone marrow of a 2-year-old male are described. Morphologically, the cells appear as flattened and epithelial-like or as small and spherical. Electron microscopy demonstrated microtubules and dense core secretory granules. The doubling time was approximately 35 hr. Isoenzyme patterns and catecholamine secretion indicated a human line of neuronal origin. The soft agar tumor colony forming system demonstrated drug resistance in vitro comparable to in vivo nonresponsiveness. The stemline karyotype of MC-NB-1 is 44,Y,del(1) (p22:), -4, -7, +del(7)(q22:), -16, +t(7;16)(16pter leads to 16q24::7q22 leads to 7q32), -17. Additionally, double-minute bodies were observed. However, no evidence of homogeneous staining regions (HSRs) were detected.  相似文献   
49.
Sixty-six bipolar I lithium clinic patients were studied for a history of psychotic symptoms at some time during the course of their illness. Agreement between different sources of information was calculated, and the patient population was divided into psychotic and non-psychotic subgroups. Probability of remaining well on lithium for the different subgroups was analyzed by the life table method. Psychosis during mania appeared to be associated with especially good early lithium prophylaxis.  相似文献   
50.
Mouse peritoneal M phi and human blood monocytes were assayed for their antitumor activity in vitro with a cytolysis, a cytostasis and a cytotoxicity test performed in parallel. Both natural and stimulus-induced M phi antitumor capacities were assessed. Results indicate that natural cytolytic activity of unstimulated M phi is generally unable to restrict final tumor cell growth, since it is not coupled with cytostatic capacity. In contrast, exposure of M phi in vitro to either MAF or IFN-beta, besides augmenting M phi cytolytic capacity, induced a very significant cytostatic activity and thus efficiently restricted the survival of tumor cells.  相似文献   
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