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HUGH F. MOLLOY F.A.C.D. ERIC LAMONT-GREGORY M.SC. CHRIS IDZIKOWSKI PH.D. F.B.PS.S. TERENCE J. RYAN D.M. F.R.C.P. 《International journal of dermatology》1993,32(9):668-672
Background. Extensive questioning of patients with a wide variety of skin disorders led to the impression that nocturnal overheating was probably an important factor in the initiation and the perpetuation of many skin disorders. Methods. In order to test the hypothesis, 12 “clean-skinned” subjects (6M/6F) aged 18 to 45 years were monitored electronically every 30 seconds during an 8 hour sleep period (2300 to 0700 hours), sleeping under a standard 10 tog duvet. Results. All the subjects were too hot by 3 to 4°C. All showed changes in their EEG patterns with reduced REM sleep, increased awakenings, and all showed changes in their sleep stage patterns. In addition, they all showed evidence of increased sweating in the “heat-sink” area. Conclusions. The mechanisms where by such changes could be implicated in the precipitation and perpetuation of skin disease are discussed. “Lifestyle” modification as a very effective, noninvasive, therapeutic regime is recommended. Further research along these lines would probably be very valuable and instructive. 相似文献
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R.T. Gun 《Australian and New Zealand journal of public health》1988,12(2):161-166
Aging and noise are the two main causes of hearing loss. To estimate the extent to which hearing loss is due to noise and is therefore preventable, an analysis was undertaken, using U.S. surveillance data, of the prevalence of hearing loss in workers in industries categorised according to the percentages of the workforce exposed to noise levels of 85 dBA or more. It was estimated that 13 per cent of the U.S. workforce was exposed to these noise levels, and that occupational noise exposure accounted for 20 per cent of self-reported hearing loss in the male workforce. Applying the industry-specific exposures to Australia, it is estimated that some 657,000 workers are exposed to noise levels of 85 dBA or more in this country. Australian Bureau of Statistics data indicate that constant noise accounts for 38 per cent of self-reported hearing loss in Australian adult males (although this figure would include hearing loss due to non-occupational noise). Data from both countries indicate that the prevalence of noise-induced hearing loss in females is negligible. 相似文献
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Ten (E)-and (Z)-isomers of 2-phenylcyclopropylamine (PCA), 1-Me-PCA, 2-Me-PCA, N-Me-PCA, and N, N-diMe-PCA and fifteeno
−, m−, p− isomers of (E)-PCA with substituents of Me, Cl, F, OMe, OH were synthesized in this laboratory and tested for the inhibition of rat brain
mitochondrial MAO-A and MAO-B. The effects of substituents, their positions, and stereochemistry on the inhibition were assessed
for the compounds with substituents at cyclopropyl and amino groups and QSAR analyses were performed using the potency data
of ring-substituted compounds. The best correlated QSAR equations are as follows: pI50=0.804 Π2 Blo−1.069 Blm+0.334 Lp−1.709 HDp+7.897 (r=0.945, s=0.211, F=16.691, p=0.000) for the inhibition of MAO-A; pI50=1.815 π-0.825 Π2 R+0.900 Es2+0.869 Es3+0.796 Es4−0.992 HDp+0.562 HAo+3.893 (r=0.982, s=0.178, F=23.351, p=0.000) for the inhibition of MAO-B. Based on the potency difference
between stereoisomers of cyclopropylamine-modified compounds and on QSAR results, it is proposed that the active sites of
MAO-A are composed of one deep hydrophobic cavity near para position, two hydrophobic cavities interacting with Me group,
a hydrophobic area accomodating phenyl and cyclopropyl backbone, steric boundaries, a hydrogen-acceptor site near para position,
and an amino group binding site and that in addition to the same two hydrophobic cavities, hydrophobic area, steric boundaries,
hydrogen-acceptor site, and amino group binding site, another steric boundary near para position and a hydrogen donating site
near ortho position constitute active sites of MAO-B. 相似文献
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Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Medial border of the perirenal space: CT and anatomic correlation 总被引:11,自引:0,他引:11
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Ana Cecília Montes Gil Raquel Lorenzetti Gun Bergsten Mendes André Moreno Morcillo Adyléia Aparecida Dalbo Contrera Toro Marcos Tadeu Nolasco da Silva Maria Marluce dos Santos Vilela 《Revista paulista de medicina》2007,125(4):205-209
CONTEXT AND OBJECTIVE: Adverse drug reactions are a significant problem in patients on antiretroviral therapy (ART). We determined liver enzyme elevation frequencies in HIV-infected children and adolescents receiving ART, and their association with risk factors. DESIGN AND SETTING: Cross-sectional study, at the Pediatrics Immunodeficiency Division, University Hospital, Universidade Estadual de Campinas. METHODS: Medical records of 152 children and adolescents (54.6% male; median age 7.48 years) were analyzed, with a mean of 2.6 liver enzyme determinations per patient. Clinically, patients were classified in categories N (6), A (29), B (78) and C (39). Serum levels of aspartate aminotransferase and alanine aminotransferase were evaluated. Hepatotoxicity was scored as grade 1 (1.1-4.9 times upper limit of normality, ULN), grade 2 (5.0-9.9 times ULN), grade 3 (10.0-15.0 times ULN) and grade 4 (> 15.0 times ULN). To assess hepatotoxicity risk factors, odds ratios (OR) and adjusted odds ratios (aOR) for age, gender, TCD4+ cell count, viral load and medication usage were calculated. RESULTS: We observed grade 1 hepatotoxicity in 19.7 % (30/152) patients. No cases of grade 2, 3 or 4 were detected. There was a significant association between hepatotoxicity and use of sulfonamides (OR, 3.61; 95% confidence interval (CI), 1.50-8.70; aOR, 3.58; 95% CI, 1.44-8.85) and antituberculous agents (OR, 9.23; 95% CI, 1.60-53.08; aOR, 9.05; 95% CI, 1.48-55.25). No toxicity was associated with ART. CONCLUSIONS: One fifth of patients experienced mild hepatotoxicity, attributed to antituberculous agents and sulfonamides. Our results suggest that ART was well tolerated. 相似文献
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测定110例肝病的抗凝血酶Ⅲ(AT-Ⅲ)活性,62例低于正常(56.4%),均值为60.1±38.2%。50例正常对照为100.0±26.7%。重症肝炎、慢性活动性肝炎及失代偿期肝硬化活性显著下降,均值分别为12.9±13.0%、51.0±34.6%、43.3±29.6%.AT-Ⅲ活性在评价肝脏功能方面较凝血酶原时间敏感,具有一定的实用意义。 相似文献