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21.
JITKA STEDRONSKA-CLAEK DAVID A. CLARK WILLIAM F. HENDRY 《American journal of reproductive immunology (New York, N.Y. : 1989)》1987,13(3):76-77
ABSTRACT: Antisperm antibodies may play a role in the pathogenesis of infertility, particularly in the male. One of the standardized methods for detecting antisperm antibodies is the tray agglutination test (TAT). Unfortunately, this assay requires fresh motile spermatozoa. Tests for binding of antibody to fixed sperm or sperm extracts have been developed as enzyme-linked immunosorbent assays (ELISA), and we compared the results of using one such ELISA method with the TAT to detect antisperm antibodies in a panel of known positive and negative sera from infertile and control patients. With respect to the TAT assay, the ELISA gave a 75% false-positive test rate and a 63% false-negative rate. It is important to validate new assays such as the ELISA before widespread application to patient screening particularly since patients judged to have antisperm antibodies may be treated with high-dose corticosteroid drugs that are not without significant side effects. 相似文献
22.
Confounding factors, bias factors and hidden variables affectthe design of experiments involving animal models. In a frequentlyused dog model for osteoarthritis these can arise, for example,because of the influence of age, sex and breed of dog. Controlsare required to investigate the progression of osteoarthritiseven in experiments forming time series. However, there areno true controls in animal models for joint degeneration. Analysisof data collected from experiments involving animal models dependson the number of factors being varied. The number of animalsinfluences the level of confidence associated with a result.Ignoring statistics can invalidate conclusions drawn from theexperiments. Statistical considerations are also important inthe presentation of results KEY WORDS: Joint degeneration, Dogs, Controls, Study design 相似文献
23.
24.
The Effect of Completeness of Medical Records on the Determination of Appropriateness of Hospital Days 总被引:1,自引:1,他引:0
25.
R.BRIAN HAYNES PhD PENNY KRIS-ETHERTON PhD RD DAVID A McCARRON MD SUZANNE OPARIL MD ALAN CHAIT MD LAWRENCE M RESNICK MD CYNTHIA D MORRIS PhD SHARON CLARK PhD DANIEL C HATTON PhD JILL A METZ PhD MARGARET McMAHON MN SCOTT HOLCOMB MS GEOFFREY W SNYDER MS F.XAVIER PI-SUNYER MD JUDITH S STERN ScD RD 《Journal of the American Dietetic Association》1999,99(9):1077-1083
26.
Retinoid-Induced Hypertriglyceridemia in Rats Is Mediated by Retinoic Acid Receptors 总被引:2,自引:1,他引:1
STANDEVEN ANDREW M.; BEARD RICHARD L.; JOHNSON ALAN T.; BOEHM MARCUS F.; ESCOBAR MARIA; HEYMAN RICHARD A.; CHANDRARATNA ROSHANTHA A. S. 《Toxicological sciences》1996,33(2):264-271
Retinoids in clinical use today are known to induce hypertriglyceridemiaas one of their major side effects. The purpose of the presentstudy was to determine, in an appropriate animal model, if retinoid-inducedhypertriglyceridemia is mediated by retinoic acid receptors(RARs) and/or by retinoid X receptors (RXRs). Oral gavage ofmale Fischer rats with 13-cis-retinoic acid for 6 days causeda rapid and sustained increase in serum triglycerides that wasreversible within 4 days posttreatment In subsequent experiments,rats were treated by gavage once daily for 3 days with variousretinoids, and serum triglyceride levels were determined 24hr after the last treatment without fasting. All-trans-and 13-cis-retinoicacid, which can be converted to both RAR and RXR agonists, and9-cis-retinoic acid, an RAR/RXR pan-agonist, caused dose-dependentincreases in serum triglycerides at doses that did not causeweight loss or mucocutaneous toxicity. Ro 136298 andAGN 190121, two RAR-specific agonists, caused dose-dependentincreases in serum triglycerides, although Ro 136298only induced hypertriglyceridemia at weight-suppressive doses.Two RXR-selective agonists, LG100268 and AGN 191701, failedto induce hypertriglyceridemia or weight loss up to the highestdoses tested. A structural isomer of AGN 190121 that does notactivate RARs or RXRs, AGN 190727, did not induce hypertriglyceridemia.Hypertriglyceridemia induced by AGN 190121 was significantlyinhibited by co-treatment with an RAR-selective antagonist,AGN 193109. Taken together, these data provide strong evidencethat retinoid-induced hypertriglyceridemia is mediated, at leastin part, by RARs. These data also suggest that RXR-specificagonists may have reduced potential to induce hypertriglyceridemiarelative to RAR-active retinoids. 相似文献
27.
Summary
- ? The aim of this small-scale study was to assess the feasibility and impact of an individualized smoking cessation intervention among clients admitted to a coronary care unit with severe angina or a first time myocardial infarction.
- ? The intervention involved in-depth nursing assessment interviews related to client beliefs, motivation and experiences of smoking, culminating in an individualized cessation plan. Participants were offered follow up support during the first year post-intervention.
- ? The findings are highly encouraging with a 77% smoking cessation rate for surviving clients within the intervention group at the end of the first year, and with 75% continued successful smoking cessation amongst surviving clients 2 years post-intervention.
28.
RAY R.; CLARK O. E. III; FORD K. W.; KNIGHT K. R.; HARRIS L. W.; BROOMFIELD C. A. 《Toxicological sciences》1991,16(2):267-274
In an effort to develop an effective centrally acting pretreatmentcompound against organophosphorus poisons, the tertiary pyridostigmine(Pyr) derivative 3-(N,N-dimethyI-carbamyloxy)-l-methyl-3-tetrahydropyridine(THP) was synthesized and studied for its anticholinesteraseproperties, as well as its efficacy against soman intoxicationin guinea pigs. Injection of THP (262 µg/kg, im) intoadult male guinea pigs caused inhibition of Wood (30%) and brain(25%) acetylcholinesterase (AChE), showing that THP penetratesthe blood-brain barrier. Pyr (131 µg/kg, im) caused AChEinhibition in the Hood (59%), but not in the brain. The inhibitorypotencies of THP and Pyr were compared by determining theirIC50 values for in vitroinhibition of both AChE (brain, erythrocyte)and pseudo-cholinesterase (plasma) in three mammalian species(guinea pig, rat, rabbit). THP, although effective in inhibitingboth types of cholinesterase, was in general less potent thanPyr. Pretreatment of guinea pigs with THP (262 µg/kg,im) plus Pyr (131 µg/kg, im). 30 min prior to subcutaneoussoman challenge, with no antimuscarink or oxime treatment, protected60% of the animals against 2 ? LD50 of soman. Neither THP norPyr alone was effective. The protective pretreatment regimendid not prevent convulsions, but shortened the recovery timein surviving animals (median recovery time 1.6 hr, comparedto 24 hr in control and other groups of animals pretreated withTHP or Pyr alone). A combination of THP and Pyr thus appearsto provide a means of evaluating the relative importance ofselective peripheral plus central vs peripheral AChE protectionagainst soman. 相似文献
29.
Finding meaning in the death of a loved one is thought to be extremely traumatic when the circumstances surrounding the death is perceived to be due to negligence, is intentional, and when the deceased suffered extreme pain and bodily harm immediately prior to death. We addressed this assumption by obtaining personal narratives and empirical data from 138 parents 4, 12, 24, and 60 months after an adolescent's or young adult child's death by accident, suicide, or homicide. Using the Janoff-Bulman and Frantz's(1997) framework ofmeaning-as-comprehensibility and meaning-as-significance, the purposes were to identify the time course to find meaning, present parents' personal narratives describing finding meaning in their experiences, identify predictors of finding meaning, and compare parents who found meaning versus those who did not on five health and adjustment outcomes. The results showed that by 12 months postdeath, only 12% of the study sample had found meaning in a child's death. By 60 months postdeath, 57% of the parents had found meaning but 43% had not. Significant predictors of finding meaning 5 years postdeath were the use of religious coping and support group attendance. Parents who attended abereavement support group were 4 times more likely to find meaning than parents who did not attend. Parents who found meaning in the deaths of their children reported significantly lower scores on mental distress, higher marital satisfaction, and better physical health than parents who were unable to find meaning. Recommendations for future research are made. 相似文献
30.
ANDREU M. CLIMENT M.Sc. MARIA S. GUILLEM Ph.D. DANIELA HUSSER M.D. FRANCISCO CASTELLS Ph.D. JOSÉ MILLET Ph.D. ANDREAS BOLLMANN M.D. 《Pacing and clinical electrophysiology : PACE》2010,33(12):1510-1517
Background: During atrial fibrillation (AF), RR interval histograms show different populations of predominant RR (pRR) intervals. These pRR intervals have been suggested to be multiples of the refractory period of the atrioventricular (AV) node or caused by the existence of a dual AV node physiology. In this study, the hypothesis that pRR intervals are related to the dominant atrial fibrillatory rate is tested. Methods: In this study, Holter electrocardiogram signals from 55 patients with persistent AF were analyzed. Number and position of pRR intervals were detected and compared with mean and standard deviation of the dominant atrial cycle length (DACL). In addition, effects of an enhancement of vagal activity and rate‐control treatments (β‐blockers and verapamil) were evaluated. Results: In all patients with more than one pRR interval and in 47% with one pRR interval, RR interval populations were statistically related with multiples of the DACL. During night activities and during β‐blockers treatment, mean ventricular rate was decreased (P < 0.01). This change was associated with a variation in the percentage of occurrences of each pRR (P < 0.01), whereas no statistical differences were present in the mean DACL or in the position of pRR intervals. A variation of the DACL due to verapamil was associated with a consistent modification in the position of the pRR intervals. Conclusion: The relation between pRR and multiples of the DACL during AF suggests that more probable RR intervals are caused by different conduction ratios of the atrial rate. (PACE 2010; 33:1510–1517) 相似文献