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11.
12.
Cell-free virus in breast milk of HIV-1-seropositive women 总被引:4,自引:0,他引:4
13.
Masquelier B Bhaskaran K Pillay D Gifford R Balestre E Jørgensen LB Pedersen C van der Hoek L Prins M Balotta C Longo B Kücherer C Poggensee G Ortiz M de Mendoza C Gill J Fleury H Porter K;CASCADE Collaboration 《Journal of acquired immune deficiency syndromes (1999)》2005,40(5):505-511
OBJECTIVES: To examine factors influencing the rate of transmitted drug resistance (TDR) among seroconverters, with particular emphasis on 3 widely used genotypic drug resistance algorithms. METHODS: The study used data from CASCADE (Concerted Action on Seroconversion to AIDS and Death in Europe), a collaboration of seroconverter cohorts in Europe and Canada. Genotypic resistance data were derived within 18 months of the last seronegative test or date of laboratory evidence of acute infection and before the initiation of antiretroviral therapy. The Stanford algorithm was used to analyze each individual's nucleotide sequence. A multivariate logistic model was used to assess independent relationships between the presence of TDR and exposure category, sex, age at seroconversion, and year of seroconversion. The paper also describes 3 alternative definitions of resistance: the Stanford algorithm, the key resistance mutations defined by the International AIDS Society, and the Agence Nationale de Recherches sur le Sida (ANRS) algorithm. RESULTS: Forty-five of 438 patients (10.3%) seroconverting between 1987 and 2003 were infected with a drug-resistant HIV-1 variant. Forty patients (9.1%) showed resistance mutations to only 1 class of antiretroviral drugs, 2 (0.5%) to 2 classes, and 3 (0.7%) to 3 classes of antiretroviral therapy. It was suggested that individuals seroconverting later in calendar time were more likely to have TDR (relative risk 3.89 and 95% CI: 0.84 to 18.02, and relative risk 4.69 and 95% CI: 1.03 to 21.31, for 1996-1999 and 2000-2003, respectively, compared with pre-1996; P trend = 0.08). This trend was apparent regardless of the definition of TDR used. The total estimated proportion of individuals with TDR varied between 10.3% and 15.5% according to which definition was used. CONCLUSIONS: Evidence was found for the rise of TDR over time. A specific definition of what constitutes TDR rather than a simple list of mutations is needed. 相似文献
14.
Paternal behavior is associated with an increase in prolactin levels in fish, birds and mammals, including rodents. The striped mouse (Rhabdomys pumilio) from southern Africa shows highly developed paternal care. We investigated whether striped mouse fathers have higher prolactin levels than nonfathers, and whether there is a relationship between tactile stimulation with pups and prolactin secretion in fathers. We measured serum prolactin in 42 male striped mice assigned to one of four different experimental groups (single males, paired males, fathers housed with mother and pups, and fathers separated from their family by a wire-mesh partition). Our results revealed no increases in prolactin levels in fathers, and fathers with tactile contact with pups did not have higher prolactin levels than the fathers that were prevented from making tactile contact with pups. In contrast, experienced males had higher prolactin levels than inexperienced males. Male striped mice are polygynous in nature, living in groups, with three breeding females, and are permanently associated with pups during the breeding season. In a field study, males had higher prolactin levels during the breeding season than during the nonbreeding season. Thus, prolactin secretion in the polygynous striped mouse might be regulated by environmental stimuli, whereas social stimuli might be important for monogamous species. This is the first study to demonstrate seasonal changes in prolactin levels in a free-living male mammal. 相似文献
15.
Mary Ann Jarvis Suntosh R. Pillay Lynn M. Norton Nemisha Hiraman Olivia B. Baloyi 《Journal of community psychology》2023,51(1):31-50
The Covid-19 pandemic lockdown regulations caused retirement homes to temporarily ban in-person visitation potentially increasing the mental health risks of older people. An opportunity arose for a multistakeholder community collaboration to design a mental health program for older people. To evaluate the process of delivering a 12-week psychosocial program aimed at preventing loneliness, countering boredom, and providing older people in restricted settings with education about Covid-19 during the lockdown, in Durban, South Africa. A qualitative retrospective design was used. Data from two focus groups and six semistructured individual interviews conducted with stakeholders (volunteers, social workers, and residents) postproject were analyzed using reflexive thematic analysis. Stakeholders had varied experiences of the project, in terms of content, processes of engagement, and implementation, resulting in five themes. The study concluded with recommendations. A strong need exists for multistakeholder community collaborations when implementing a program where the context restricts physical access. 相似文献
16.
In the operative resection of brain tumors, defining and locating edges of deep-seated tumors or those with indistinct color and consistency can be difficult. This report presents a simple yet precise, alternative method, using the basic Brown-Roberts-Wells or Cosman-Roberts-Wells stereotactic frame, for placement of visual markers to aid in tumor resections. The method can also be extended to the Leksell system. Using routine computed tomographic scanning or magnetic resonance imaging after stereotactic frame application, multiple points along tumor edges were used as target points. In the operating room, standard techniques were used for the skin incision, removal of the bone flap, and opening the dura. At each target point, after opening the dura and using stereotactic coordinates and equipment, a microbiopsy forceps was used to place "micropatties" (each with a string tail) or small catheters with pledgets or catheter tips located at tumor edges. After removing the arc, the tumor resection was accomplished in a conventional nonstereotactic manner by simply following string tails or catheters to the tumor. Gross tumor edges were determined from positions of actual patties or catheter tips. These simple but accurate techniques offer the possibility of tumor resections under stereotactic guidance with equipment readily available to most neurosurgeons. The fidelity of marker placement is also maintained in relation to tumor edges despite shifts in the tumor and/or brain as cystic areas are drained or large amounts of the tumor are resected. 相似文献
17.
Primary graft dysfunction after liver transplantation 总被引:5,自引:0,他引:5
Chui AK Shi LW Rao AR Anasuya A Hagl C Pillay P Verran D McCaughan GW Sheil AG 《Transplantation proceedings》2000,32(7):2219-2220
18.
A descriptive analysis of STD prevalence among urban pregnant African-American teens: data from a pilot study. 总被引:3,自引:0,他引:3
Ralph J Diclemente Gina M Wingood Richard A Crosby Eve Rose Delia Lang Allan Pillay John Papp Carol Faushy 《The Journal of adolescent health》2004,34(5):376-383
OBJECTIVE: To assess the prevalence of sexually transmitted diseases (STDs) among a sample of African-American adolescent females at the time of their first prenatal visit and to assess key characteristics of those testing positive for sexually transmitted diseases. The study also determined differences in these characteristics between adolescents who were and those who were not diagnosed with an STD. METHODS: One-hundred-and-seventy pregnant African-American adolescents (aged 14-20 years; mean = 17.5 years) receiving their first prenatal visit were recruited at a prenatal clinic located in a large urban hospital. Biological assessment included nucleic acid amplification testing for gonococcal, chlamydial, and trichomonal infections. Rapid plasma reagin testing assessed infection with syphilis. A self-administered survey and in-depth face-to-face interview were used to collect detailed information assessing adolescents' sociodemographic characteristics, psychosocial indices, and their recent sexual risk behaviors. Data were analyzed using Student's t-tests and contingency table analyses, respectively, for continuous and categorical variables. RESULTS: Overall, 23.5% tested positive for one of the four STDs. Thirteen percent were infected with Chlamydia trachomatis, 1.2% with Neisseria gonorrhoeae, 8.9% with Trichomonas vaginalis, and 1.2% with Treponema pallidum. More than one-half reported recent (past 6 months) treatment for an STD, 30% of these tested positive for at least one of the four STDs assessed. Adolescents testing positive for STDs held favorable attitudes toward condom use, but levels of sexual risk were generally high. There were no sociodemographic, psychosocial, and sexual-risk differences between those testing positive and negative. CONCLUSION: Findings support STD screening efforts targeting pregnant adolescents. Providing clinic-based counseling and prevention education programs to pregnant adolescents regardless of apparent risk factors may also be warranted. 相似文献
19.
Polycystic ovary syndrome and endometrial cancer 总被引:3,自引:0,他引:3
An association between polycystic ovary syndrome (PCOS) and endometrial carcinoma was first suggested in 1949. Since then, several studies have been published that appear to support this association, and it is common practice among gynecologists and physicians to prescribe hormonal treatment to reduce this perceived risk, although there is no consensus as to the subgroup of PCOS in whom this is required. The mechanism(s) underlying any association are also unclear, but it is again widely assumed that chronic anovulation, which results in continuous estrogen stimulation of the endometrium unopposed by progesterone, is a major factor. However, obesity, hyperinsulinemia, and hyperandrogenism, which are also features of PCOS, are risk factors for endometrial carcinoma, but it does not necessarily follow that the incidence or mortality from endometrial cancer is increased in women with the syndrome. Potential strategies to prevent endometrial cancer in PCOS women are discussed. 相似文献
20.