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941.
Retinopathy is a likely complication of diabetes mellitus, and optometrists who manage patients with diabetes must be prepared to recognize the disease, educate the patient, communicate with the physician treating the disease, and follow up as appropriate to minimize the opportunity for undiagnosed complications. Liability most often results from failure to diagnose diabetic retinopathy, failure to monitor retinopathy adequately, and failure to refer or obtain consultation in a timely manner. Care for patients with diabetes should include appropriate record-keeping and documentation. 相似文献
942.
Metallic taste has been reported from divers working with underwater electric welding and cutting. An in vitro model was designed to simulate the intraoral situation of the divers with respect to the magnetic field. Potentiostatic analyses were performed on amalgam samples exposed to AC and DC magnetic fields. Morphologic changes were analyzed using differential interference light microscopy and scanning electron microscopy. Chemical changes on the surface of the amalgam samples were analyzed with secondary ion mass spectrometry. Results demonstrated that dental amalgams exposed to a specific AC magnetic field underwent morphologic and chemical changes in the superficial amalgam layers. 相似文献
943.
944.
A study of the interaction of alcohol drinking and tobacco smoking among French cases of laryngeal cancer. 总被引:3,自引:0,他引:3
P Guénel J F Chastang D Luce A Leclerc J Brugère 《Journal of epidemiology and community health》1988,42(4):350-354
Laryngeal cancer represents an important cause of cancer in France, and the individual effects of alcohol and tobacco on this cancer site are well known. However the problem of the interaction between these agents is less extensively documented, and the role of the high consumptions of alcohol has not been studied frequently. A case-control analysis was undertaken to investigate the joint effect of alcohol and tobacco by comparing 197 glottic and 214 supraglottic cancer cases to 4135 controls representative of the French general population. Heavy drinkers were available from the two groups of cases, the highest alcohol category being equivalent to a consumption of more than 2 litres of wine per day. The relative risks estimated for heavy drinkers and smokers were high, and the results indicated an even stronger effect of alcohol drinking and tobacco smoking on the upper part of the laryngeal region. Additive and multiplicative models were fitted to the data. The multiplicative hypothesis was found to be the most appropriate, implying that the risks associated with alcohol and tobacco multiply when the exposures occur simultaneously. The public health implications of this result and the contribution of heavy drinkers and smokers to the frequency of upper respiratory and digestive tract cancers are discussed. 相似文献
945.
A. S. Pinto M. de Lana B. Bastrenta C. Barnabé V. Quesney S. Noël M. Tibayrenc 《Parasitology research》1998,84(5):348-353
A total of 15 mixtures involving 9 different stocks attributed to the 19/20, 32 and 39 major clonal genotypes of Trypanosoma cruzi were used to infect third-instar nymphs of Triatoma infestans via an artificial feeding device. Three biological parameters were considered: (1) the percentage of infected insects (%II),
(2) the number of flagellates per insect (NFI), and (3) the percentage of trypomastigotes per insect (%DIF). Genetic characterization
by both multilocus enzyme electrophoresis (MLEE) and random amplification of polymorphic DNA (RAPD) indicated that in almost
all cases (87%), mixtures remained present after completion of the whole cycle in the insect vector. Two lines of comparison
were performed: (1) pure clonal genotypes versus corresponding mixed clonal genotypes and (2) the␣actual behavior of mixed
clonal genotypes versus the expected behavior of the theoretical mixture (i.e. the␣arithmetic mean of the results observed
for each of the two clonal genotypes taken separately). Statistical analyses of the variables were made difficult because
of the presence of large standard deviations. Nevertheless, in several cases, mixtures differed significantly from pure clonal
genotypes, and in one case the actual mixture differed significantly from the theoretical mixture. In some cases, interaction
(either potentialization or reciprocal inhibition) could be suspected.
Received: 10 March 1997 / Accepted: 21 September 1997 相似文献
946.
947.
Ileal and jejunal resections were carried out to investigate their effect on the faecal bile acid excretion and on the development of 1,2-dimethylhydrazine (DMH)-induced colonic cancer in rats. Both resection types raise the total daily faecal bile acid level compared to the control sham-operated group, whereas ileal resection has a more pronounced effect. The incidence of tumours was found higher in groups with enhanced faecal bile acid level. Our findings show a connection between the daily faecal bile acid excretion and the incidence of DMH-induced colonic cancer. 相似文献
948.
L G Szollár I Mészáros L Tornóci K Rischák M Molnár S Mányai 《Journal of cardiovascular pharmacology》1990,15(6):911-917
Forty-five patients with mild hypertension were treated for 2 months with either metoprolol or pindolol in a randomized, blind, crossover study. The effects of metoprolol (100-300 mg/day) and pindolol (5-15 mg/day) on triglyceride (TG), cholesterol (C), high-density lipoprotein cholesterol (HDL-C), and HDL subfraction (HDL2-C and HDL3-C) levels were compared in males and females separately. Pindolol and metoprolol significantly elevated (10% above baseline level) the plasma TG level in both males and females. After metoprolol treatment, the HDL-C level remained unchanged in both sexes; however, a shift was found between HDL2-C and HDL3-C:HDL2-C decreased and a concomitant elevation in HDL3-C was observed. Pindolol significantly decreased total C, HDL-C, and HDL2-C levels in males. A similar trend (although the changes were not significant) was found in females. The results demonstrate the role of beta blockers in the inhibition of TG-rich lipoprotein elimination. These findings suggest that during long-term administration of metoprolol and pindolol, risks and benefits from beta-blocker therapy must be carefully considered. Continuous monitoring of lipid profiles is suggested during this treatment in order to avoid the potential worsening effect of beta blockers on risk factors of ischemic heart disease. 相似文献
949.
A Czeizel M Kovács P Kiss K Méhes L Szabo E Oláh G Kosztolányi G Szemere H Kovács G Fekete 《Genetic epidemiology》1988,5(3):183-202
A population-based study of 7,049 index patients with multiple congenital abnormalities (MCA) born in Hungary during 1973-1982 was organized by the Hungarian Center for Congenital Anomaly Control. All clinically recognized syndromes and associations which were submitted (2,049) were accepted without any further follow-up. New or supplementary information was requested in the case of unspecified MCA (320). A copy of detailed necropsy records was requested from pathologists in lethal cases (2,022). Following these steps, apparent but not true instances of MCA were excluded (399), and an attempt was made to assign as many of the remainder as possible in 17 well-delineated MCA entities (900). The living index patients with severe MCA were referred where possible to the regional centers for evaluation (864). One hundred and seventy entities were identified, and seven cases were excluded as not representing MCA. In the so-called 3,393 unidentified cases for which no diagnosis was possible, the component abnormalities were tabulated according to their number. The final count was 6,643 cases with MCA, which is equivalent to a birth prevalence of 4.0 per 1,000 total births, and to 10% of recorded cases with congenital anomalies. As a result of this program the proportion of recognized syndromes and associations among children with MCA increased from 29% to 47%. The accuracy of diagnoses has improved, e.g., the occurrence of unspecified cases decreased from 4.5% to 2%. As a result of this study, the number of chromosomal (1,700), Mendelian (557), and teratogenic (104) syndromes and associations (758) was considerably greater than the initial notifications indicated. 相似文献
950.
Ana Lucia Z. Rosso MD James P. Mattos MD PhD Sérgio A. P. Novis MD PhD 《Clinical autonomic research》1993,3(5):299-301
Acase of periodic sweating with multifocal dystonia is reported in a 60-year-old woman. At the age of 48 years, she presented with involuntary twisting of the lower face on the right. Six months later she noticed similar movements in the head and right arm. Four years later she began having attacks of generalized sweating over the whole face, anterior region of the trunk and both arms. The attacks occurred hourly each and every day. They lasted for about 10 min and were followed by voluntary urinary voiding. The biochemical and laboratory investigations showed no abnormalities except for the luteinizing hormone and follicle-stimulating hormone values that were below normal. The computerized tomography and magnetic resonance imaging scans revealed a suprasellar cyst. Clonazepam was introduced with partial improvement of the dystonic movements but not of the sweating attacks. The patient refused surgery. Acetazolamide was added and reduced the sweating attacks. We speculate that the periodic sweating may be related to cerebrospinal fluid production and cyst enlargement, hence the ability of acetazoleamide, which reduces cerebrospinal fluid production, to reduce attacks. 相似文献