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991.
Blake DR Kearney MH Oakes JM Druker SK Bibace R 《Archives of pediatrics & adolescent medicine》2003,157(6):523-529
BACKGROUND: Many young people at highest risk for chlamydial infection do not use chlamydia screening services. OBJECTIVES: To describe young people's beliefs and opinions about obstacles to and motivators for obtaining testing and to provide recommendations for how to improve youth participation in chlamydia screening programs. METHODS: Eight focus group interviews (4 male and 4 female groups) were conducted with young people using a semistructured interview guide. Thirty-two male and 23 female volunteers (mean age, 18.2 years; age range, 15-24 years) were recruited from Job Corps and Department of Youth Services sites. The main outcome measure was categorization of textual data using content analysis techniques. Data were coded by 2 investigators into categories of responses based on research questions and spontaneously offered comments. Satisfactory intercoder agreement was achieved. RESULTS: Participants described many obstacles to testing, including concern that someone will know they were tested or tested positive, fear about discovering they have a sexually transmitted disease, and fear of acquired immunodeficiency syndrome. Many participants were unsure what physical effects chlamydia produced or thought it was possible to die of a chlamydial infection. Participants recommended providing more information about the effects of chlamydia, availability of urine testing, and ease of treatment to motivate more young people to seek testing. They also emphasized the need to make sexually transmitted disease screening services more private and confidential. There was an overwhelming interest in using a home Chlamydia test (much like a home pregnancy test) if one were available. CONCLUSIONS: To increase youth participation in screening programs, it will be necessary to address their concerns, dispel misconceptions, and provide more information about chlamydia. A home Chlamydia test might be one way to increase screening. 相似文献
992.
993.
Gordinier ME Malpica A Burke TW Bodurka DC Wolf JK Jhingran A Ramirez PT Levenback C 《Gynecologic oncology》2003,90(3):625-628
OBJECTIVE: The objective of this study was to investigate the cause of groin recurrence in patients with vulvar cancer who had negative nodes in their superficial inguinal lymphadenectomy (SIL) specimens. METHODS: The records of patients with vulvar cancer treated at M. D. Anderson Cancer Center between 1986 and 1997 were reviewed to identify patients with squamous histology, clinical and surgical stage I or II, depth of invasion greater than 1 mm, and primary treatment consisting of radical wide excision and SIL. One hundred four patients met these criteria. Among these, nine experienced recurrent disease that involved one or both of the groins. All of the original hematoxylin and eosin (H&E)-stained slides were reviewed by one pathologist (AM). Then, each paraffin block containing nodal tissue was recut at 40 microm intervals to obtain five sections for H&E staining and two unstained sections to be used for cytokeratin immunostaining if necessary. RESULTS: The median age at diagnosis and primary surgery was 65 years and the median depth of invasion was 4 mm. Seven patients underwent bilateral, and two underwent unilateral, groin dissections. The median number of lymph nodes removed per groin was seven. The median time to recurrence was 22 months. A total of 785 additional H&E-stained slides were prepared and examined at 100x and 400x magnification. No micrometastases were identified, and there were no other suspicious findings. Therefore, immunohistochemical staining was not performed. At recurrence, one patient had a biopsy only, and eight had attempted surgical resection. In two patients, tumor was identified in fibroadipose tissue only; no lymph nodes were identified. Among the other six patients, the median number of lymph nodes resected at the time of the recurrence was five (range 1 to 10). At last report, six patients had died and three were alive and free of disease. Median follow-up for survivors was 63 months (range 42 to 71). CONCLUSION: These data strongly suggest that groin relapse in patients with negative nodes on SIL is caused by metastatic disease in unresected inguinal nodes. SIL as performed on the patients in this study did not eliminate all sites of nodal metastasis. 相似文献
994.
995.
Aae,an autotransporter involved in adhesion of Actinobacillus actinomycetemcomitans to epithelial cells 下载免费PDF全文
The periodontal pathogen Actinobacillus actinomycetemcomitans possesses myriad virulence factors, among them the ability to adhere to and invade epithelial cells. Recent advances in the molecular manipulation of this pathogen and the sequencing of strain HK 1651 (http://www.genome.ou.edu/act.html) have facilitated examination of the genetics of its interaction with epithelial cells. The related gram-negative organism, Haemophilus influenzae, possesses autotransporter adhesins. A search of the sequence database of strain HK 1651 revealed a homologue with similarity in the pore-forming domain to that of the H. influenzae autotransporter, Hap. A. actinomycetemcomitans mutants deficient in the homologue, Aae, showed reduced binding to epithelial cells. A method for making A. actinomycetemcomitans SUNY 465 transiently resistant to spectinomycin was used with conjugation to generate an isogenic aae mutant. An allelic replacement mutant was created in the naturally transformable A. actinomycetemcomitans strain ATCC 29523. Lactoferrin, an important part of the innate host defense system, protects against bacterial infection by bactericidal and antiadhesion mechanisms. Lactoferrin in human milk removes or cleaves Hap and another autotransporter, an immunoglobulin A1 protease, from the surface of H. influenzae, thereby reducing their binding to epithelial cells. Human milk whey had similar effects on Aae from A. actinomycetemcomitans ATCC 29523 and its binding to epithelial cells; however, there was little effect on the binding of SUNY 465. A difference in the genetic structure of aae in the two strains, apparently due to the copy number of a 135-base repeated sequence, may be the cause of the differential action of lactoferrin. aae is the first A. actinomycetemcomitans gene involved in adhesion to epithelial cells to be identified. 相似文献
996.
Cox JT Schiffman M Solomon D;ASCUS-LSIL Triage Study 《American journal of obstetrics and gynecology》2003,188(6):1406-1412
OBJECTIVE: The purpose of this study was to determine the risk of cumulative cervical intraepithelial neoplasia (CIN) grade 2 or 3 according to initial colposcopy and directed biopsy results among women with low-grade squamous intraepithelial lesions (LSIL) or human papillomavirus (HPV) DNA positive atypical squamous cells of undetermined significance (ASCUS). STUDY DESIGN: A 2-year follow-up of 897 cases of LSIL and 1193 cases of HPV DNA positive ASCUS from the ASCUS/LSIL Triage Study was used to simulate American Society for Colposcopy and Cervical Pathology Consensus Conference recommendations. Women with CIN grade 1 or less were followed up for 2 years by semiannual cytologic examination, with universal exit colposcopy. The clinical end point was a cumulative clinical center histologic diagnosis of CIN grade 2 or 3. RESULTS: The cumulative risk of CIN grade 2 or 3 was equivalent for LSIL (27.6%) and HPV positive ASCUS (26.7%). After excluding the women with a diagnosis of CIN grade 2 or 3 at initial colposcopy and directed biopsy (17.9%), the remaining women were at nearly identical risk for subsequent CIN grade 2 or 3 regardless of initial colposcopy result (completely negative colposcopy-11.3%; negative colposcopically directed biopsy-11.7%; and CIN grade 1 biopsy-13.0%). CONCLUSION: LSIL and HPV positive ASCUS are clinically equivalent. Initial colposcopic detection of obviously prevalent CIN grade 2 or 3 reduces risk. However, for the remaining women who have CIN grade 1 or less on colposcopy and directed biopsy, the risk for subsequent CIN grade 2 or 3 (whether missed, prevalent, or truly incident) is approximately 12% over 2 years. This risk does not vary meaningfully by initial distinction of histologic CIN grade 1 from negative colposcopy and biopsy. 相似文献
997.
Noble L Hand I Haynes D McVeigh T Kim M Yoon JJ 《American journal of perinatology》2003,20(8):477-483
The objective of our study was to identify factors associated with the initiation of breast-feeding in a poor urban area. One hundred postpartum, nonadolescent, non-drug using mothers, 50 breast-feeding and 50 formula feeding, were consecutively interviewed. Breast-feeding women were more likely to be born outside of the United States (42 versus 14%, p = 0.002), have more years of education (12.1 +/- 1.9 versus 10.9 +/- 1.7, p = 0.002), be employed either prior to or during pregnancy (38 versus 16%, p = 0.000), be married (46 versus 26%, p = 0.037), be a nonsmoker (86 versus 64%, p = 0.011), have more prenatal visits (8.4 +/- 7.3 versus 5.0 +/- 5.9, p = 0.010), or have a breast-feeding mother (48 versus 26%, p = 0.023). There were no differences in age or ethnicity. The father of the breast-feeding baby was more likely to be better educated (12.0 +/- 2.8 versus 10.5 +/- 3.6 years, p = 0.022) and to work full-time (68 versus 40%, p = 0.005). Eighty-four percent of formula feeders knew that breast milk was better for their babies but decided not to breast-feed due to concerns of pain, smoking, and work. Sixty-three percent of women made the choice to breast-feed prior to the pregnancy, 26% during the pregnancy, and 11% after delivery. Significantly more multiparas decided prior to the pregnancy compared with primaparas. We recommend that breast-feeding education should be started prior to the first pregnancy and tailored to the concerns of the women. 相似文献
998.
Mao C Hughes JP Kiviat N Kuypers J Lee SK Adam DE Koutsky LA 《American journal of obstetrics and gynecology》2003,188(3):677-684
OBJECTIVE: The purpose of this study was to identify clinical signs and symptoms associated with detection of human papillomavirus (HPV) DNA in the female genital tract. STUDY DESIGN: A total of 516 university students (18 to 24 years old) enrolled in a cohort study that included the collection of genital specimens for HPV DNA testing every 4 months for up to 4 years. Reported symptoms and objective clinical findings of women with and without HPV DNA were compared by multivariate analysis. RESULTS: Acute and persisting HPV infections were not associated with discharge, itching, burning, soreness, or fissures. Clinical evidence of genital warts was statistically associated only with HPV types 6 and 11. Detection of any HPV DNA was associated with bacterial vaginosis (BV). Furthermore, a time lag analysis suggests that HPV infection usually precedes detection of BV. CONCLUSION: Most women who acquire genital HPV infection are asymptomatic; some, however, are at increased risk for BV. 相似文献
999.
OBJECTIVE: This study was undertaken to determine blood flow changes in the large cerebral arteries during normal pregnancy. STUDY DESIGN: Ten healthy pregnant volunteers underwent velocity-encoded phase contrast magnetic resonance imaging at 4 time intervals: 14 to 16, 28 to 32, and 36 to 38 weeks' gestation, and at 6 to 8 weeks' postpartum. Analysis consisted of serial paired Student t tests, with P<.05 considered significant. RESULTS: By using postpartum values for comparison, cerebral blood flow decreased by 14 to 16 weeks in the middle cerebral artery (P<.001), but was not significantly changed in the posterior cerebral artery. Significant decreases occurred in both the middle (P<.0001) and posterior (P=.002) cerebral arteries in late pregnancy. CONCLUSION: An approximately 20% reduction in large artery cerebral blood flow occurs during normal pregnancy, secondary to changes in velocity, whereas the area of these vessels remains unchanged. These findings may represent generalized vasodilatation of downstream resistance arterioles, assuming constant blood flow at the tissue level. 相似文献
1000.
Effect of raloxifene on the response to conjugated estrogen vaginal cream or nonhormonal moisturizers in postmenopausal vaginal atrophy 总被引:1,自引:0,他引:1
Parsons A Merritt D Rosen A Heath H Siddhanti S Plouffe L;Study Groups on the Effects of Raloxifene HCI With Low-Dose Premarin Vaginal Cream 《Obstetrics and gynecology》2003,101(2):346-352
OBJECTIVE: To study the effect of raloxifene on the response to conjugated estrogen cream or nonhormonal moisturizer in postmenopausal women with preexisting signs of vaginal atrophy. METHODS: Postmenopausal women with preexisting and untreated vaginal atrophy were enrolled in this parallel, placebo-controlled, randomized study. A total of 187 women were randomized to four treatment groups: daily oral raloxifene (60 mg per day) or a placebo in a double-blind manner plus one application of conjugated estrogen cream (0.5 g) or one applicator full of nonhormonal moisturizer, open label. The conjugated estrogen cream or nonhormonal moisturizer was applied daily for the first 2 weeks, and then twice weekly thereafter for 3 months. Efficacy of treatment regimens on signs and symptoms of vaginal atrophy was evaluated by monitoring objective and subjective parameters. RESULTS: Signs and symptoms of vaginal atrophy improved in all four treatment groups. Raloxifene did not diminish the magnitude of improvement when administered with either vaginal preparation. Conjugated estrogen cream produced a statistically greater improvement in signs (P <.05) but not in individual symptoms or overall satisfaction relative to nonhormonal moisturizer. CONCLUSION: Postmenopausal women with evidence of preexisting vaginal atrophy may use either low-dose conjugated estrogen cream or nonhormonal moisturizer to treat the atrophy concurrently with raloxifene (60 mg per day). 相似文献