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991.
The amount of endothelial cell loss that occurs to the donor cornea during the trephination process was evaluated in 40 porcine eyes. A vital staining technique (alizarin red S and acid violet 19) was used to quantify the extent of endothelial damage and removal. Two types of corneal punches (Weck and H&I0 were used for trephination. The average amount of endothelial loss from the peripheral cornea was 7.9%, accounting for only a 3% loss of endothelial cells over the total surface area of the corneal button. a comparison of the Weck and H&I corneal punches showed no significant difference (P greater than 0.1) by Student's test for both endothelial cell damage and removal. 相似文献
992.
The effect of lysozyme-inactivation on L(+)-lactic acid (LA) production in dental plaque suspensions was evaluated. From 10 children 24-h plaque was collected and lysozyme activity inhibited by addition of goat antiserum to human lysozyme. Acid production was stimulated by addition of glucose. The results showed significantly increased LA levels (50-150%) in lysozyme-inactivated plaque suspensions from 8 of the subjects compared to untreated controls. The increase in acid production activity was not related to plaque lysozyme levels. The findings indicate that the presence of lysozyme may be limiting on acid production in the early dental plaque. 相似文献
993.
Regulation of guinea pig ileal electrolyte transport by M3-muscarinic acetylcholine receptors in vitro 总被引:2,自引:0,他引:2
To determine the muscarinic receptor subtype mediating guinea pig ileal mucosal electrolyte secretion, we compared the potencies (Kb) of selective M1 (pirenzepine) (PZ), M2 (AF-DX 116, methoctramine), and M3 [4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP), hexahydrosiladifenidol (HHSiD)] antagonists as inhibitors of carbachol-induced reductions in guinea pig atrial heart rate and ileal longitudinal muscle contractions, responses mediated by M2 and M3 receptors, respectively. Pretreatment with all five muscarinic antagonists shifted the carbachol concentration-response curve to the right, in a manner suggesting competitive antagonism. The following affinity profiles (Kb, nM) were obtained for: 1) ileal mucosa: 4-DAMP (2.7) greater than HHSiD (23.0) greater than PZ (110) greater than or equal to methoctramine (395) greater than AF-DX 116 (784); 2) atrial heart rate: 4-DAMP (9.5) congruent to methoctramine (11) greater than AF-DX 116 (63) greater than HHSiD (222) greater than PZ (256); and 3) ileal longitudinal muscle: 4-DAMP (3.1) greater than HHSiD (21) greater than PZ (143) greater than methoctramine (388) greater than or equal to AF-DX 116 (482). The selectivity profiles of these antagonists suggest that muscarinic receptors in the ileal mucosa more closely resemble those in the ileal muscle (M3) than those in atrial muscle (M2). Moreover, M1-muscarinic receptors appear to be relatively unimportant in mediating the effects of carbachol on short circuit current (ISC). Carbachol-induced increases in ISC were also unaffected by pretreatment with 0.5 microM tetrodotoxin, suggesting that electrolyte transport in the guinea pig ileal mucosa may be mediated, in part, by postsynaptic M3-muscarinic receptors on the enterocytes. 相似文献
994.
G Durrieu P Valet M Berlan A Villeneuve J L Montastruc 《European journal of pharmacology》1990,182(3):597-601
Treatment of dogs for 21 days with oral levodopa (100 mg b.i.d.) plus benserazide (25 mg b.i.d.) induced a significant increase in the number of platelet alpha 2-adrenoceptors labelled by [3H] yohimbine with no change in Kd. The rise was maximal at the end of the treatment and remained significant during the month following the cessation of treatment. Plasma catecholamine levels did not vary. Competition experiments showed a low affinity of both dopamine and levodopa for platelet alpha 2-adrenoceptors. These results suggest that levodopa treatment regulates alpha 2-adrenoceptor number in dog platelets. 相似文献
995.
The authors screened for alcoholism 145 consecutive patients who presented with sexual dysfunction or disorders. Using the Michigan Alcoholic Screening Test (MAST), 29% of the patients scored in the probable alcoholic range. Probable alcoholics were more likely to present without a partner and claimed higher sex drive than nonalcoholic patients. Probable alcoholic males reported less joy and vigor than probable alcoholic females, while the reverse held for the nonalcoholic groups. Blind to the MAST results, the staff made six alcohol-related diagnoses and referred one patient for alcohol treatment. The authors discussed the importance of training faculty and resident staff in the relationship of alcohol abuse associated with psychosexual dysfunctions. 相似文献
996.
J. Rutenfranz W. Ottmann B. Neidhart W. Brockmann 《International archives of occupational and environmental health》1988,61(1-2):89-93
Summary A typical shiftwork experiment was chosen to prove the validity of an automated procedure for the analysis of free noradrenaline and adrenaline in urine. The method consists of a column switching technique with an adsorption/elution clean-up and a reversed phase high performance liquid chromatography followed by chemical reaction detection based on the trihydroxyindole method. The analysis of variance was performed using a second data set obtained by a semi-automated procedure for which the accuracy had already been confirmed. The analysis of covariance showed that for field studies, as well as for laboratory experiments in which the variances contributed by the experiments themselves are greater than 10% rel., the data sets of the two methods provide the same information.Dedicated to Prof. H. Hartkamp, University of Wuppertal, on the occasion of his 60th birthday 相似文献
997.
An occupational history of exposure to organic solvents, defined as daily occupational exposure for at least one year, was more common among 167 men with newly diagnosed non-Hodgkin's lymphoma than among 130 healthy referents from the general population (38 versus 14%). Categorization in five-year age groups gave 3.3 as a Mantel-Haenszel estimate of the odds ratio (95% CI 1.9-5.8). The odds ratio was 6.5 (95% CI 3.2-13.3) for localized supradiaphragmatic tumors and 2.3 (95% CI 1.3-4.3) for other lymphoma presentations. In a logistic model including age and organic solvent, phenoxy acid, and chlorophenol exposure, it could be shown that solvent exposure was an independent risk factor and that no important interaction occurred between the risk factors. With increasing duration of exposure there was a significantly increased risk of lymphoma, a finding implying a dose-response relationship. There was no significant difference in tumor histology between the exposed and unexposed patients. These findings support the concept that occupational exposure to organic solvents is a risk factor for non-Hodgkin's lymphoma. The results also confirm a strong association between such exposure and an initial supradiaphragmatic location of the lymphomas. 相似文献
998.
L Grau 《Women & health》1988,14(3-4):75-91
Currently it is estimated that up to 25 percent of the elderly manifest symptoms of mental disorder. The recognition of the seriousness of the problem has lead to a growing body of research in the field of geriatric mental health. This paper presents an overview of early gerontological studies of life satisfaction and morale of older persons and of the two most prevalent mental health problems of the aged, depression and dementia. Mental health service delivery and utilization issues are also considered. 相似文献
999.
LUCAS D.; MENEZ J. F.; BODENEZ P.; BACCINO E.; BARDOU L. G.; FLOCH H. H. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1988,23(1):23-31
Acetaldehyde, the first metabolite of ethanol, reacts with haemoglobinin vitro to produce acetaldehydehaemoglobin adducts.Some clinical studies on the minor haemoglobins have suggestedthat these adducts may be formed in people abusing alcohol.Under hydrolysis of haemoglobin, with oxalic acid at 100°Cin sealed vials, some acetaldehyde was released and then specificallydetermined by HPLC. The kinetics of hydrolysis were studiedusing haemoglobin previously labelled with 14[C] acetaldehyde.The maximum liberation of 14[C] acetaldehyde was obtained after3 hr 30 min hydrolysis and this time factor was then utilizedin the analysis of alcoholic and control haemoglobin. Thus,we have confirmed the formation of acetaldehyde haemoglobinadducts in vivo. It must be noted that the released acetaldehydecorresponds only to an index of the stable adducts. The levelswere higher in alcoholics than in controls (1.417±0.171and 1.295±0.139 nmol/mg Hb, respectively, P<0.001).In conclusion, this marker is not a convenient tool for themonitoring of alcohol exposure levels because of the low differencesbetween alcoholic and control haemoglobins. 相似文献
1000.
L R?stam R V Luepker M B Mittelmark D M Murray J S Slater H Blackburn 《American journal of preventive medicine》1988,4(5):249-254
To determine the potential effect of screening on referral patterns, an adult population sample (4,404 men, 5,164 women, 20-69 years of age) was systematically recruited and screened for hypercholesterolemia and then analyzed by different cholesterol referral recommendations. Using levels suggested by the Lipid Research Clinics Coronary Primary Prevention Trial (greater than or equal to 265 mg/dL), 7.3% of men and 5.8% of women would be referred for follow-up. With the suggested recommendations of the National Cholesterol Education Program (NCEP), (greater than or equal to 200 mg/dL), 49.2% of men and 40.2% of women would be referred. The use of age-related definitions of the NIH Consensus Conference on Lipid Lowering results in 28.0% referrals in men and 21.8% in women. From this population, hypercholesterolemia subjects (greater than or equal to 265 mg/dL at screening; n = 624) were invited for a second cholesterol determination (58% returned), which found 36% below the 265 mg/dL level. Population screening for cholesterol is likely to produce large numbers of patients for follow-up, with the actual numbers strongly dependent on cutoff levels and age-sex distributions. Referral and follow-up of these patients may place a significant load on an unprepared health care community. 相似文献