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41.
SUMMARY The purpose of this study was to identify predictors of risk behaviors among college students and to determine how students differed in HIV risk practices. Participants were from six colleges and universities in a large southeastern metropolitan area. The present analysis was limited to participants who were 18 to 25 years of age; single; White, African American, or Asian; and reported initiation of sexual intercourse. The results demonstratedsignificant associations of gender and race with having sex within the past3 months, number of partners, condom use, length of time one knew one's sexual partner, substance use, and asking one's partner about sexualhistory. Using Chi-Square Automatic Interaction Detection (CHAID), the strongest predictor of condom use was noted to be gender, and the strongest predictor of number of partners was race. The findings of this study indicate that HIV risk factors vary dependingon a college student's ethnicity, gender, academic status, and substanceuse. Most importantly, African American men, particularly men who use drugs, and White and Asian men who use alcohol tend to report higher numbers of sexual partners. Females, particularly upperclass White females, and White men who do not use alcohol report infrequent condom use. These findings areuseful for health educators who have begun to recognize the importance ofconsidering the HIV risk factors of students and incorporating informationrelated to these factors into HIV prevention programs. From the results ofthis study, we have several suggestions that health educators and researchersmay want to consider when developing programs for college students: 1. Although students may not need extensive information about basic HIVfacts, they may need reinforcement of the information. In particular, students need to be made aware that lambskin condoms do not offer protection against HIV transmission. 2. Females need to be encouraged and taught the skills to negotiate theuse of and to actually use condoms. These skills need to be reinforced throughout college, particularly as women adopt other methods of birth control (i.e., the pill). 3. The general acceptance of condom use among African Americans and Asians may be a useful tool for the health educator. Promoting and reinforcingthis norm and behavior, while addressing some of the other risk factors inthese groups, may be a particularly effective approach to HIV prevention. 4. For White students whose condom use rates are lower, messages can include the use of condoms for STD and pregnancy protection. Messages for male students could include control over preventing pregnancy or sharing control for pregnancy prevention. 5. Couples often abandon using condoms when they feel they know each other “well enough.” Some guidelines for when to give up condoms might also be given to provide couples with responsible and realistic directions for minimizing their risk when choosing to engage in unprotected sex. These guidelines would include HIV testing two times at least 6 months apart, no evidence of STDs in either partner, and a commitment of both partners to a monogamous relationship. 6. When addressing the number of sexual partners as a risk factor, African American men and women may hold the greatest potential for change, given the greater likelihood of multiple partners in these groups. 7. With respect to drug and alcohol use, health educators may want to include discussions about the influence of drugs (particularly for African American students) and alcohol (particularly for White and Asian students) on inhibiting logical decision-making as it relates to sexual intercourse.  相似文献   
42.
The "nonspecific" esterases are a family of enzymes that were originally identified because of their reaction with synthetic O-acetyl ester substrates. While the electrophoretic polymorphisms of these enzymes have been extremely useful for genetic studies, their biological functions have remained completely unknown. Esterase D is characterized by its reactivity with 4-methylumbelliferyl acetate. This enzyme has recently been of particular interest because of its tight linkage to the putative recessive gene causing retinoblastomas, and to the recessive gene causing Wilson disease. We describe here the partial purification of a human erythrocyte esterase that appears to be highly specific for O-acetylated sialic acids. We next present evidence that suggests that esterase D is identical to this sialic acid-specific O-acetylesterase. First, both activities copurify from human erythrocyte lysates through several different purification steps, each of which use different principles of separation. Second, both activities show a remarkably similar profile of inhibition with a variety of different agents. Third, they both show a nearly identical heat-inactivation profile. This cytosolic sialic acid-specific O-acetylesterase appears to be involved in the "recycling" of O-acetylated sialic acid molecules. Thus, esterase D may be the first nonspecific esterase for which a specific biological role can be predicted.  相似文献   
43.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Nach der Collectivity-of-Drinking-Cultures-Theorie von Skog finden Veränderungen des Alkoholkonsums in allen...  相似文献   
44.
BackgroundLeukopenia is a common complication after kidney transplantation. The etiology is multifactorial, with medication adverse effects and cytomegalovirus infection as main causes. Optimal strategies to prevent or treat posttransplant leukopenia remain unknown. We aimed to identify risk factors for leukopenia and to investigate the benefit of switching the immunosuppressive therapy to hydrocortisone as a continuous infusion.MethodsWe retrospectively evaluated all patients with leukopenia after kidney transplantation between 2007 and 2017 at our center relative to age- and sex-matched controls.ResultsLeukopenia was associated with the degree of rejection therapy before leukopenia, the immunosuppressive therapy before transplantation, and an induction therapy with rabbit antithymocyte globulin. Patients with leukopenia exhibited increased mortality, an increased incidence of bacterial and viral infections, and more acute rejections. Switching to hydrocortisone as a continuous infusion in patients with severe leukopenia decreased the duration of leukopenia and the incidence of subsequent viral infections, especially with cytomegalovirus.ConclusionLeukopenia is a risk factor for infectious complications and mortality, and it is associated with acute rejection. Switching immunosuppressive therapy to hydrocortisone as a continuous infusion is a safe approach to reduce the duration of leukopenia and the incidence of viral infections.  相似文献   
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46.
Pathology techniques developed over the past decade may be successfully applied to the diagnosis of orbital disease. Tissue specimens may be immunophenotyped by immunohistochemical staining and flow cytometry. Immunohistochemical staining provides a qualitative analysis of localization of antigenic determinants and flow cytometry provides a quantitative analysis. The molecular biologic technique of polymerase chain reaction enables detection of minute amounts of material by amplification from DNA primers. Fine-needle aspiration biopsy is an alternative to open biopsy in select cases. The most important concept regarding these techniques is communication with the ophthalmic pathologist regarding the collection and interpretation of the specimen.  相似文献   
47.
In an open-label, randomized trial using a 3 x 3 Latin square design, single doses of 24 mg of the ACE inhibitor spirapril, or 50 mg hydrochlorothiazide, or their combination were given to 18 healthy male volunteers. No alteration in the area under plasma drug concentration curve (AUC), peak plasma level, time to peak level, or elimination half-life was detected for hydrochlorothiazide, spirapril, or its active metabolite, spiraprilat, during combination therapy. It was concluded that there was no significant effect of spirapril on single-dose kinetics of hydrochlorothiazide, nor of hydrochlorothiazide on single-dose kinetics of spirapril. Significant reductions in systolic blood pressure were noted 2--6 h after either spirapril or combination treatment, but no evidence of any synergistic effect of single-dose effects on blood pressure was seen during combination therapy.  相似文献   
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49.
BACKGROUND: Despite many randomized controlled trials, the merits of laparoscopic appendectomy remain unclear. A meta-analysis may provide insights not evident from any individual studies. DATA SOURCES: Systematic literature search yielded 17 trials (1,962 subjects) of true randomized design with usable statistical data comparing laparoscopic and conventional appendectomy in adults. The effect sizes for operating time, hospitalization, postoperative pain, return to normal activity, wound infection, and intra-abdominal abscess were calculated, using the random effects model to allow for heterogeneity. An estimate of the robustness of all positive findings was also calculated. RESULTS: Modest but statistically significant effect sizes were found for four of the six outcome measures. Laparoscopic appendectomy takes 31% longer to perform, but results in less postoperative pain, faster recovery (by 35%), and lower wound infection rates (by 60%). CONCLUSION: Laparoscopic appendectomy offers significant improvement in postoperative outcomes at the cost of a longer operation.  相似文献   
50.
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