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991.
OBJECTIVES: To compare HIV seroprevalence and sexual risk behavior among very young gay and bisexual men (aged 15-17 years) and their older counterparts (aged 18-22 years). To examine drug-use patterns and correlates of sexual risk behavior in both of these age groups. DESIGN AND METHODS: An interviewer-administered cross-sectional survey of 719 gay and bisexual males between 15 and 22 years old was conducted through a venue-based sampling design. Blood specimens were collected and tested for HIV antibodies, hepatitis B, and syphilis. Interviews assessed sexual and drug-use behavior as well as psychosocial variables believed to be related to sexual risk-taking, including self-acceptance of gay or bisexual identity, perceptions of peer norms concerning safer sex, and perceptions of the ability to practice safer sex (safer sex self-efficacy). RESULTS: Of the 719 participants, 100 (16.2%) were aged between 15 and 17 years. HIV seroprevalence was somewhat lower among those aged 15 to 17 years (2.0%) compared with those aged 18 to 22 years (6.8%). Overall, the prevalence of hepatitis-B core antibody was significantly lower in the younger age group (5.0%) than in the older group (14.1%). The men aged 15 to 17 years used alcohol, ecstasy, and heroin less frequently than those aged 18 to 22 years. The age groups did not differ in the proportion of men who reported any unprotected anal intercourse in the previous 6 months (31.2%). In both age groups, use of amphetamines, ecstasy, and amyl nitrate was associated with unprotected anal intercourse. Self-acceptance of gay or bisexual identity was related to less sexual risk for those aged 15 to 17 years. In both age groups, greater safer sex self-efficacy was linked to less HIV sexual risk-taking. In the younger group, perceptions of peer norms that support safer sex were related to less risk behavior. CONCLUSIONS: Very young gay and bisexual men engage in unprotected anal sex at rates comparable with those for their somewhat older counterparts, raising serious concern over their risk of acquiring HIV infection. To prevent seroconversions, interventions must target those <18 years of age, and prevention programs should address the use of certain drugs in relation to sex and sexual risk-taking. To be most effective, programs should develop innovative communication strategies to take into account lack of self-acceptance of gay or bisexual identity and low self-efficacy for practicing safer sex.  相似文献   
992.
A patient presented with atrial tachycardia. The work-up, guided by the tachycardia morphology, led to the diagnosis of left atrial appendage aneurysm. Surgical removal of the atrial appendage resulted in cure of the tachycardia and associated symptoms.  相似文献   
993.
PURPOSE: Herbal therapies are unconventional treatments that have been used for several different diseases. PC-SPES is an herbal mixture, composed of eight different herbs (chrysanthemum, isatis, licorice, Ganoderma lucidum, Panax pseudo-ginseng, Rabdosia rubescens, saw palmetto, and scutellaria), which has been used as an alternative in the treatment of prostate cancer. We report two cases of hormone-refractory prostate cancer patients, who showed a favorable response to therapy with this herbal combination, controlling the progression of the disease. METHODS: We report two cases of biopsy proven prostate cancer patients with metastatic disease, treated with total androgen blockade, progressing to an androgen-independent status. These patients were offered traditional therapies for hormone-resistant prostate cancer, and they chose to take PC-SPES. The follow-up as well as their evolution are described. RESULTS: PC-SPES extract decreased the prostate-specific antigen (PSA) value for both patients from an initial value of 100 and 386 ng/mL to 24 and 114 ng/mL after 1 year and 4 months, respectively, remaining stable until now. No gynecomastia or hot flashes were observed in these patients and the treatment was well tolerated. CONCLUSION: PC-SPES has shown a strong estrogenic in vitro and in vivo activity as an alternative tool in the management of prostate cancer patients. These cases suggest that PC-SPES might have some potential activity against hormone-independent prostate cancers.  相似文献   
994.
995.
996.
Sesame food allergy (SFA) in children is an increasingly recognized one in many countries. Our objective was to describe the course and natural history of SFA. Seventy-four patients sensitized to sesame were evaluated using clinical records, questionnaires, skin prick tests (SPT), in vitro specific immunoglobulin (sIg) E, and oral challenges (OC) and categorized into three groups: group A: patients who experienced allergic reaction after ingestion of sesame-containing food (n = 45); group B: patients evaluated for atopic dermatitis and found to be sesame SPT-positive (n = 11); group C: patients with sensitization to sesame allergen (n = 18). Group A patients were followed for an average of 6.7 yr. Analysis of our results revealed that 76% of patients in group A developed the allergy by the age of 2. The median age at onset of allergy in these patients was 1 yr. Immediate reaction to a minimal amount of sesame was characteristic. Skin was the most common site of involvement, followed by respiratory and gastrointestinal systems. Tolerance developed in only 20% of the patients. High sIgE (>0.15 IU) was demonstrated only in 75% of those in which it was examined. Sixteen patients performed oral sesame food challenge which was found positive in 88%. No correlation was found between the size of SPT and the level of in vitro sesame IgE antibodies, the outcome of OC results, and the development of tolerance to sesame. In conclusion, SFA tends to appear early in life, but unlike cow's milk and egg allergy, persists in 80% of the cases. Typical reactions combined with positive sesame SPT are reliable for diagnosis.  相似文献   
997.
Community-associated methicillin-resistant Staphylococcus aureus is an established pathogen in many centres in the United States, but has yet to establish a firm foothold in Canada. In the present article, the authors report, to their knowledge, Canada’s first fatal paediatric case of invasive disease due to community-associated methicillin-resistant S aureus and review its pathogenesis, epidemiology and treatment.  相似文献   
998.
999.
PURPOSE: Alternatives to axillary lymph node dissection (ALND) are being developed amid controversy surrounding the therapeutic benefit and overall utility of this routine surgical procedure. Although potential negative side effects associated with ALND are known, we set out to examine whether these side effects contribute significantly to patient reports of quality of life and mental health. PATIENTS AND METHODS: We surveyed 222 women who had received an ALND as part of breast cancer surgery. All women underwent a physical therapy assessment of range of arm/shoulder motion and completed the Modified Post-operative Pain Questionnaire, the Pain Disability Index, the McGill Pain Questionnaire (short form), the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, and the Mental Health Inventory. RESULTS: Seventy-two percent of the women experienced arm/shoulder pain, weakness, or numbness in the week before the interview, and range of motion of the affected arm/shoulder was impaired in 73% of the women. Severity of pain was reported to be low to moderate, and younger patients experienced greater pain than older patients. Pain severity correlated positively with the number of lymph nodes removed and receipt of chemotherapy and was not significantly related to length of time since surgery or receipt of radiation therapy. Generally high levels of cancer-specific quality of life and mental health were reported. Quality of life was significantly predicted by the McGill Pain Questionnaire, and mental health was significantly predicted by the Pain Disability Index and the physical therapy assessment. CONCLUSION: Surgery-related symptoms after ALND persist for a majority of women with breast cancer and are not significantly related to time since surgery or receipt of radiation therapy. These symptoms and associated disability are significantly predictive of cancer-specific quality of life and mental health.  相似文献   
1000.
Pathological studies suggest that cisplatin injures different portions of the nephron to different extents. To investigate this issue further, we examined the cytotoxicity and uptake of cisplatin in cell lines derived from S1 and S3 proximal tubule and distal convoluted tubule segments isolated from a mouse carrying the SV40 large T-antigen transgene. S1 cells displayed the highest sensitivity to cisplatin cytotoxicity, followed by S3 and distal convuluted tubule (DCT) cells. These differences in cytotoxicity did not correlate with differences in cisplatin uptake. Cytotoxic concentrations of cisplatin triggered apoptosis in all three cell lines. Although BAX and BCL-2 expression was similar among the three cell lines, the expression of the anti-apoptotic protein, BCL-XL, was significantly lower in S1 cells than in S3 and DCT cells, and this may have contributed to the heightened sensitivity of S1 cells. Cisplatin transport characteristics demonstrated a saturable component of cisplatin uptake and differences in apparent KM and Vmax values among the three cell lines. The three cell lines were 43- to 176-fold more sensitive to cisplatin than to carboplatin. This distinction between the two drugs could not be fully explained by differences in the uptake rates of carboplatin and cisplatin. We conclude that cells from different portions of the nephron display different sensitivities to cisplatin, different transport characteristics for cisplatin and different levels of expression of BCL-XL. In addition, the relative resistance of renal cells to carboplatin vs cisplatin is mostly due to the differential effects that follow internalization. © 1999 Cancer Research Campaign  相似文献   
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