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<正>Mycobacterium tuberculosis is the primary bacteria that leads to human tuberculosis(TB),which usually affects the pulmonary organs. TB is one of the top 10 causes of death worldwide;however, China is one of eight countries that together account for two-thirds of the total number of cases globally.  相似文献   
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《Vaccine》2020,38(32):4940-4943
To determine the duration of immunity provided by the Hepatitis A vaccination (HepA), we evaluated a cohort of participants in Alaska 20 years after being immunized as infants. At recruitment, participants received two doses of inactivated HepA vaccine on one of three schedules. We conducted hepatitis A antibody (anti-HAV) testing for participants at the 20-year time-point. Seventy-five of the original 183 participants (41%) were available for follow-up. The overall anti-HAV geometric mean concentration was 29.9 mIU/mL (95% CI 22.4 mIU/mL, 39.7 mIU/mL) and 50 participants (68%) remained seropositive (titer ≥ 20 mIU/mL). Using a fractional polynomial model, the predicted percent seropositive at 25 years was 55.3%, 49.8% at 30 years and 45.7% at 35 years, suggesting that the percent sero-positive could drop below 50% earlier than previously expected. Further research is necessary to understand if protection continues after seropositivity diminishes or if a HepA booster dose may become necessary.  相似文献   
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Although the numbers of newly reported diagnoses of AIDS decreased in the 1990s, it is not clear whether they reflect a decreasing number of new HIV infections. Direct measurement of HIV incidence through follow-up cohort studies is difficult and costly. We estimated HIV incidence and trends in incidence among men who have sex with men (MSM) and heterosexual men and women at clinics for sexually transmitted diseases (STDs) by using a recently developed serologic testing algorithm that requires only a single blood specimen. Cross-sectional anonymous serosurveys were conducted at 13 STD clinics in nine cities in the United States from 1991 through 1997. Before anonymous HIV testing, demographic and clinical information was abstracted. Of 129,774 specimens tested, 362 (0.28%) were from persons estimated to be recently infected. Incidence among MSM was 7.1% (95% confidence interval (CI): 4.8-10.3), 14 times higher than that among heterosexuals, which was 0.5% (CI: 0.4- 0.7). Incidence among MSM and heterosexuals remained unchanged during the time studied. Decreasing rates of new AIDS diagnoses in the 1990s do not reflect stable rates of new HIV infections among MSM and heterosexual patients attending these clinics.  相似文献   
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OBJECTIVE: To describe the prevalence of crack cocaine use in an HIV-infected population and to examine the association between crack use after HIV diagnosis and high-risk sexual behaviors for heterosexual men, heterosexual women, and men who have sex with men (MSM). METHODS: Analysis of cross-sectional interviews conducted from January 1995 through December 1998 with HIV infected adults in 12 states. RESULTS: Of 10,415 persons with HIV or AIDS, 66.6% never used crack, 10.7% used crack before HIV diagnosis but not after, and 22.7% used crack after diagnosis. High-risk sexual behaviors were more prevalent among those who had ever used crack and were most prevalent among those who used crack after diagnosis. In multivariable analyses, crack use after diagnosis was associated with having multiple sex partners and trading sex for drugs/money in all three groups: heterosexual men, heterosexual women, and MSM. For heterosexual women and MSM, crack use after diagnosis was associated with unprotected sex with a main partner, and among heterosexual men and MSM, with unprotected sex with casual partners. CONCLUSIONS: Crack use after HIV diagnosis was associated with high-risk sexual behaviors. Treatment programs to assist people in quitting crack are needed to help reduce the risk of HIV transmission from this population.  相似文献   
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OBJECTIVES: We determined proportions of high-risk persons tested for HIV, the reasons for testing and not testing, and attitudes and perceptions regarding HIV testing, information that is critical for planning prevention programs. METHODS: Cross-sectional interview study of persons at high risk for HIV infection (men who have sex with men [MSM]; injection drug users [IDUs]; and heterosexual persons recruited from gay bars, street outreach, and sexually transmitted disease clinics) among six states participating in the HIV Testing Survey (HITS) in 1995 to 1996 (HITS-I) and 1998 to 1999 (HITS-II). RESULTS: Overall testing rates were lower in the HITS-I (1226/1599 [77%]) than in the HITS-II (1375/1711 [80%]) (p =.01). Persons <25 years old tested less frequently than those >or=25 years old (HITS-I: 71% vs. 78%, respectively, p=.007; HITS-II: 63% vs. 85%, respectively, p<.001). The main reasons for testing and not testing were the same in both surveys, but the proportions of reasons for not testing differed (e.g., "unlikely exposed to HIV" [HITS-I (17%) vs. HITS-II (30%), p<.0001], "afraid of finding out HIV-positive" [HITS-I (27%) vs. HITS-II (18%), p<.0001]). Attitudes regarding HIV testing differed among tested and untested respondents, especially among MSM. CONCLUSIONS: HIV testing rates were higher in the HITS-II, but testing rates decreased among the youngest respondents. Denial of HIV risk factors and fear of being HIV-positive were the principal reasons for not being tested. Availability of new HIV therapies may have contributed to decreased fear of finding out that one is HIV infected as a reason to avoid testing. The increased proportion of persons at risk who did not test because they believed they were unlikely to have been exposed highlights the need for prevention efforts to address risk perceptions.  相似文献   
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BACKGROUND: Meta-analysis and randomized clinical trial results reported in June 1998 indicated a significant reduction in perinatal HIV transmission rates among mothers undergoing a cesarean section (C-section). OBJECTIVE: The objective of this study was to examine recent trends in and factors associated with C-section deliveries among HIV-infected women in the United States. DESIGN: A multisite pediatric medical record review of a cohort of HIV-exposed and HIV-infected infants in the Pediatric Spectrum of HIV Disease (PSD) Cohort study (n = 6467) and the national Pediatric HIV/AIDS Reporting System (HARS) (n = 8,306) was conducted. SETTING/PATIENTS: All infants born between 1994 and 2000 to HIV-positive mothers referred to the PSD study or to a Pediatric HARS hospital or clinic site were enrolled. RESULTS: The proportion of deliveries by C-section was steady at about 20% from 1994 through June 1998. From July 1998 through December 2000, this proportion increased to 44% in the PSD study and to nearly 50% in the Pediatric HARS. On analysis by multiple logistic regression, delivery of infants by C-section was associated with the release of study results (OR = 2.83), delivery in four PSD sites in reference to Texas (OR: 2.02-1.43), having private medical care reimbursement (OR = 1.62), and having maternal prenatal care (OR = 1.43). CONCLUSIONS: The PSD and Pediatric HARS data demonstrate a sharp increase in C-section rates mainly among HIV-infected women in the United States after the release of the meta-analysis and randomized clinical trial results in 1998. This finding highlights the rapid impact of study results on obstetric practice. It underscores the critical role of prenatal care in offering perinatal interventions such as scheduled C-section when indicated to reduce the likelihood of HIV transmission.  相似文献   
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This meta-analysis examines the efficacy of international HIV prevention interventions designed to reduce sexual risk behavior of men who have sex with men (MSM). We performed a comprehensive search of published and unpublished English-language reports of HIV prevention interventions that focus on MSM and evaluated changes in risky sexual behavior or biologic outcomes related to sexual risk. Data from 33 studies described in 65 reports were available as of July 2003. Studies with insufficient data to calculate effect sizes were excluded from the meta-analysis. Interventions were associated with a significant decrease in unprotected anal intercourse (odds ratio [OR] = 0.77, 95% confidence interval [CI]: 0.65-0.92) and number of sexual partners (OR = 0.85, 95% CI: 0.61-0.94) and with a significant increase in condom use during anal intercourse (OR = 1.61, 95% CI: 1.16-2.22). Interventions successful in reducing risky sexual behavior were based on theoretic models, included interpersonal skills training, incorporated several delivery methods, and were delivered over multiple sessions spanning a minimum of 3 weeks. Behavioral interventions provide an efficacious means of HIV prevention for MSM. To the extent that proven HIV prevention interventions for MSM can be successfully replicated in community settings and adapted and tailored to different situations, the effectiveness of current HIV prevention efforts can be increased.  相似文献   
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《Vaccine》2022,40(48):6947-6955
BackgroundHuman papillomavirus (HPV) infections were the main cause of anogenital cancers and warts. HPV 6/11/16/18 vaccines provide protection against the high-risk types of HPV responsible for 70% of cervical cancers and 90% of genital warts. This randomized, blinded, non-inferiority phase III trial was to determine whether immunogenicity and tolerability would be non-inferior among women after receiving two novel 4- and 9-valent HPV vaccines (4vHPV, HPV 6/11/16/18; 9vHPV, HPV 6/11/16/18/31/33/45/52/58) compared with those receiving Gardasil 4 (4-valent).Methods1680 females between 20 and 45 years were randomized in a 2:1:1 ratio to 20–26, 27–35, or 36–45 y groups. Subjects then equally assigned to receive 4vHPV, 9vHPV or Gardasil 4 (control) vaccine at months 0, 2, and 6. End points included non-inferiority of HPV-6/11/16/18 antibodies for 4vHPV versus control, and 9vHPV versus control and safety. The immunogenicity non-inferiority was pre-defined as the lower bound of 95% confidence interval (CI) of seroconversion rate (SCR) difference > ?10% and the lower bound of 95% CI of geometric mean antibody titer (GMT) ratio > 0.5.ResultsAmong the three vaccine groups, more than 99% of the participants seroconverted to all 4 HPV types. The pre-specified statistical non-inferiority criterion for the immunogenicity hypothesis was met: all the lower bounds of 95% CIs on SCR differences exceeded ?10% for each vaccine HPV type and the corresponding lower bounds of 95% CIs for GMT ratios > 0.5. Across vaccination groups, the most common vaccination reaction were injection-site adverse events (AEs), including pain, swelling, and redness. General and serious AEs were similar in the three groups. There were no deaths.ConclusionsThis study demonstrated that the novel 4- and 9-valent HPV vaccination was highly immunogenic and generally well tolerated, both of which were non-inferior to Gardasil 4 in immunogenicity and safety.  相似文献   
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