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排序方式: 共有667条查询结果,搜索用时 31 毫秒
1.
SUSAN AVERY VIRGINIA N. BOLTON BRIDGETT A. MASON 《International journal of andrology》1990,13(2):93-99
The ability of sperm to swell in hypo-osmotic conditions was examined in 211 semen samples from the partners of patients about to undergo oocyte retrieval for in-vitro fertilization (IVF). The test was performed using aliquots of semen, the remainder of which was then prepared for IVF. No significant difference was found, in either the percentage of swollen sperm or the type of swelling response, between samples that achieved fertilization in vitro and those that did not, or between any of the diagnostic categories of infertility (tubal damage, unexplained infertility, oligospermia). In samples which achieved fertilization in vitro there were correlations between sperm swelling and sperm motility (r = -0.51) and abnormal morphology (r = 0.33), but no such correlations were demonstrated in samples that failed to achieve fertilization. Moreover, there was no significant difference between the percentage of swollen sperm in semen (mean motility 64%), in samples immediately after preparation for IVF (mean motility 96%) or in capacitated sperm 24 h after preparation (mean motility 91%). These results demonstrate that the hypo-osmotic sperm swelling test does not assist in the prediction of the fertilizing capacity of human sperm in vitro. 相似文献
2.
PAUL CHRISTINE L.; SANSON-FISHER ROBERT W.; REDMAN SELINA; CARTER SUSAN 《Health promotion international》1994,9(4):241-248
Accidental injury in the home is a major cause of death andill-health among young children. Reducing home safety hazardsby the use of safety devices such as stair barriers and safetytaps has the potential to prevent home injuries. Little is knownabout levels of home safety hazards or how to encourage parentsto reduce hazards. The Safe Place Project examined parents'knowledge of home safety and the prevalence of safety hazardsin homes where there were young children. The study also evaluatedthe effectiveness of a low-cost strategy aimed at reducing homesafety hazards. The strategy used trained volunteers to providehome safety checks and tailored safety education in conjunctionwith increasing the availability of home safety devices. Onehundred and six families with young children participated inthe project. Some homes contained many hazards, with 43% ofthe sample having more than 10 home safety hazards. At follow-up,the intervention group showed a significant reduction in homehazards and a trend towards an increase in knowledge of homesafety. 相似文献
3.
CLOSED CHAMBER SYSTEM FOR DELIVERY OF ETHANOL TO CELL CULTURES 总被引:3,自引:0,他引:3
ADICKES EDWARD D.; MOLLNER TERESA J.; LOCKWOOD SUSAN K. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1988,23(5):377-381
The accuracy and consistency of the delivery of ethanol to culturedcells is important to determine effects on morphologic, biochemicaland physiologic alterations. Open and closed chamber systemswere evaluated to determine cytotoxic vs sublethal, potentiallyteratogenic effects on neonatal rat cardiac myocytes. The open system employed a variety of cell culture vessels.Cardiac cells were exposed directly to ethanol in the growthmedia at concentrations of 550 mM in Petri dishes, multiwellslides and multiwell chambers. Ethanol concentrations in themedia in these open vessels decreased over 60% in a 24 hr incubationperiod. A closed system consisted of tightly sealed plastic containersin which the same vessels were used. The vessels were placedon a platform over a bath of ethanol-water. Cells were acclimatedfor 24 hr with ethanol in the bath at 200% of the final desiredmedia concentration. Ethanol gradually diffused into the mediato reach peak levels of 5, 10,25 or 50 mM at 24 hr. After the24 hr period, ethanol was added to both the media and bath atthe desired concentration. Cells exposed gradually to ethanol in the closed chambers remainedviable, but showed slower division and growth. A period of gradualacclimation is required to induce sublethal cellular effectsrather than lethal effects. The diversity of cell systems andmanipulations of cultures to study the potential teratogeniceffects of ethanol are improved using such a closed chambersystem. 相似文献
4.
ANDREW SHERWOOD SUSAN S. GIRDLER EDITH E. BRAGDON SHEILA G. WEST KIMBERLY A. BROWNLEY ALAN L. HINDERLITER KATHLEEN C. LIGHT 《Psychophysiology》1997,34(2):185-191
In this study we examined test-retest stability of cardiovascular stress responses over a decade of the life span. Participants were 55 male college undergraduates. 19 years of age at initial testing, and 29 years of age at follow-up testing Stressors were a foot cold pressor and an aversive reaction time task. Cardiovascular measures included systolic and diastolic blood pressure, heart rate, and preejection period. For cold pressor, the magnitude and pattern of cardiovascular responses remained unchanged at the 10-year follow-up. For the reaction time task, the characteristic cardiovascular response patterns was preserved but with significant attenuation of magnitude. The present findings are consistent with previous observations of temporal stability but over a substantially longer test-retest interval. The long-term stability of stress responses is discussed in the context of stress test methodology, behavioral response demands, and maturation of the physiological systems involved in cardiovascular response expression. 相似文献
5.
CHERYL K. ROTH AD RNC BONNIE RILEY RN CCRN SUSAN M. COHEN DSN RN 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1992,21(4):310-311
Advances in technology and complex care have enabled women with various health problems to become and remain pregnant. Consequently, health-care practitioners are seeing an increasing number of pregnant women who have aortic aneurysms. This case study describes the culturally sensitive intrapartum care of a Middle Eastern woman with ascending and descending aortic aneurysms. 相似文献
6.
SUSAN MATTSON RNC CTN Ph D LILLIAN LEW RD MEd 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1992,21(1):48-54
OBJECTIVE: To evaluate the success of the Southeast Asian Health Project in terms of client satisfaction with the prenatal care and other services. To obtain additional data about Southeast Asian women's health practices regarding childbearing. DESIGN: Survey through questionnaires administered as interviews. SETTING: In clients' homes or via telephone. PARTICIPANTS: 119 women from SEAHP's case files of recently delivered clients. MEASUREMENTS AND MAIN RESULTS: Interviews were conducted by four community workers fluent in Cambodian or Lao. The majority of women were satisfied with SEAHP, particularly the interpretation and education in native languages. Women were also satisfied with SEAHP, encouraging others to seek care. CONCLUSIONS: SEAHP appears to meet prenatal care needs of Southeast Asian women in Long Beach, California. More objective outcome data await analyses, but the program's approach may ensure access to and use of health services. 相似文献
7.
Overview of studies on drinking patterns and consequences 总被引:1,自引:0,他引:1
SUSAN J. BONDY 《Addiction (Abingdon, England)》1996,91(11):1663-1674
Research on selected consequences of alcohol use are reviewed in terms of now alcohol use is measured and reported in research designs common to that area of study. In addition, evidence of the probable underlying mechanisms by which alcohol leads to the various consequences is examined, particularly in relation to the aspects of drinking pattern which are theoretically most relevant to the outcome. There is considerable variation in the degree to which research in these areas stresses pattern of drinking (as opposed to average amount consumed or total dose). Ideally, theoretical consideration of underlying causal links should determine data collection and analysis techniques. 相似文献
8.
9.
Oral bropirimine (an immunomodulator shown to induce interferon)was administered to timed-pregnant Sprague-Dawley rats in fiveexperiments utilizing several different dosing schedules. Concentrationsof 100, 200, and 400 mg/kg of bropirimine were used. Interferonlevels were determined in maternal serum, spleen, and wholeembryo extracts and uterine contents were evaluated for survivalof the embryos. Maternal toxicity occurred in all experimentsas evidenced by dose-related decreases in body weight duringthe first 24 hr postdosing. Hematoxicology analyses of maternalserum revealed significant decreases in urea nitrogen, potassium,and albumin, along with increases in aspartate transaminase,alanine transaminase, and total bilirubin, in bropirimine-treateddams as compared to the vehicle controls. In addition, the meansfor maternal thymus weight decreased while the means for spleenweight increased with increasing concentration of bropirimine.As compared to the vehicle controls, interferon titers werehigh in maternal serum, maternal spleen, and, to a lesser extent,whole embryos, 2 hr postdosing, but had decreased or were belowdetectable levels 24 hr postdosing. Embryolethality was pronounced(increases in pre- and postimplantational loss) after a singledose (Gestation Day 3, 4, 5, 8, 9, or 10) of bropirimine, aswell as after 7 or 8 consecutive days (Gestation Days 612or 613) of treatment. Although embryotoxicity never occurredin these experiments in the absence of pronounced maternal toxicity,the pregnant dams never died as the result of bropirimine treatment,whereas the embryos frequently failed to survive. 相似文献
10.
Dietary Changes Favorably Affect Bone Remodeling in Older Adults 总被引:4,自引:0,他引:4
ROBERT P. HEANEY MD DAVID A. McCARRON MD BESS DAWSON-HUGHES MD SUZANNE OPARIL MD SARAH L. BERGA MD JUDITH S. STERN ScD SUSAN I. BARR PhD CLIFFORD J. ROSEN MD 《Journal of the American Dietetic Association》1999,99(10):1228-1233
OBJECTIVE: To determine whether dietary counseling to increase milk intake could produce useful changes in the calcium economy and what, if any, other nutrition-related changes might be produced. DESIGN: Randomized, open trial. SUBJECTS/SETTING: Two hundred four healthy men and women, aged 55 to 85 years, who habitually consumed fewer than 1.5 servings of dairy foods per day. Six academic health centers in the United States. INTERVENTION: Subjects were instructed to consume 3 servings per day of nonfat milk or 1% milk as a part of their daily diets, or to maintain their usual diets, for a 12-week intervention period, which followed 4 weeks of baseline observations. MAIN OUTCOME MEASURES: Energy and nutrient intake assessed from milk intake logs and 3-day food records; serum calciotrophic hormone levels at baseline and at 8 and 12 weeks; urinary excretion of calcium and N-telopeptide at 12 weeks. STATISTICAL ANALYSES: Repeated-measures analysis of variance. RESULTS: In the milk-supplemented group, calcium intake increased by 729 +/- 45 mg/day (mean +/- standard error), serum parathyroid hormone level decreased by approximately 9%, and urinary excretion of N-telopeptide, a bone resorption marker, decreased by 13%. Urine calcium excretion increased in milk-supplemented subjects by 21 +/- 7.6 mg/day (mean +/- standard error), less than half the amount predicted to be absorbed from the increment in calcium intake. All of these changes were significantly different from baseline values in the milk group and from the corresponding changes in the control group. Bone-specific alkaline phosphatase level (a bone formation marker) fell by approximately 9% in both groups. Serum level of insulin-like growth factor-1 (IGF-1) rose by 10% in the milk group (P < .001), and the level of insulin-like growth factor binding protein-4 (IGFBP-4) fell slightly (1.9%) in the milk group and rose significantly (7.9%) in the control group (P < .05). APPLICATIONS/CONCLUSIONS: The changes observed in the calcium economy through consumption of food sources of calcium are similar in kind and extent to those reported previously for calcium supplement tablets. The increase in IGF-1 level and the decrease in IBFBP-4 level are new observations that are beneficial for bone health. Important improvements in skeletal metabolism can feasibly occur in older adults by consumption of food sources of calcium. Dietitians can be confident that food works, and that desired calcium intakes can be achieved using food sources. 相似文献