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891.
892.
Latka MH Fielding K Gray GE Bekker LG Nchabeleng M Mlisana K Nielson T Roux S Mkhize B Mathebula M Naicker N de Bruyn G Kublin J Churchyard GJ;HVTN Phambili study team 《PloS one》2012,7(4):e31387
Background
HIV prevention trials are increasingly being conducted in sub-Saharan Africa. Women at risk for HIV are also at risk of pregnancy. To maximize safety, women agree to avoid pregnancy during trials, yet pregnancies occur. Using data from the HVTN 503/“Phambili” vaccine trial, we report pregnancy incidence during and after the vaccination period and identify factors, measured at screening, associated with incident pregnancy.Methods
To enrol in the trial, women agreed and were supported to avoid pregnancy until 1 month after their third and final vaccination (“vaccination period”), corresponding to the first 7 months of follow-up. Unsterilized women, pooled across study arms, were analyzed. Poisson regression compared pregnancy rates during and after the vaccination period. Cox proportional hazards regression identified associations with first pregnancy.Results
Among 352 women (median age 23 yrs; median follow-up 1.5 yrs), pregnancy incidence was 9.6/100 women-years overall and 6.8/100 w-yrs and 11.3/100 w-yrs during and after the vaccination period, respectively [Rate Ratio = 0.60 (0.32–1.14), p = 0.10]. In multivariable analysis, pregnancy was reduced among women who: enrolled at sites providing contraception on-site [HR = 0.43, 95% CI (0.22–0.86)]; entered the trial as injectable contraceptive users [HR = 0.37 (0.21–0.67)] or as consistent condom users (trend) [HR = 0.54 (0.28–1.04)]. Compared with women with a single partner of HIV-unknown status, pregnancy rates were increased among women with: a single partner whose status was HIV-negative [HR = 2.34(1.16–4.73)] and; 2 partners both of HIV-unknown status [HR = 4.42(1.59–12.29)]. Women with 2 more of these risk factors: marijuana use, heavy drinking, or use of either during sex, had increased pregnancy incidence [HR = 2.66 (1.24–5.72)].Conclusions
It is possible to screen South African women for pregnancy risk at trial entry. Providing injectable contraception for free on-site and supporting consistent condom use may reduce incident pregnancy. Screening should determine the substance use, partnering, and HIV status of both members of the couple for both pregnancy and HIV prevention.Trial Registration
SA National Health Research Database DOH-27-0207-1539; Clinicaltrials.gov NCT00413725相似文献893.
894.
Christoph?ScheichEmail author Dietmar?Leitner Volker?Sievert Martina?Leidert Brigitte?Schlegel Bernd?Simon Ivica?Letunic Konrad?Büssow Anne?Diehl 《BMC structural biology》2004,4(1):4
Background
High-throughput protein structure analysis of individual protein domains requires analysis of large numbers of expression clones to identify suitable constructs for structure determination. For this purpose, methods need to be implemented for fast and reliable screening of the expressed proteins as early as possible in the overall process from cloning to structure determination. 相似文献895.
Sensory characterization of Nile tilapia croquettes enriched with flaxseed flour using free‐choice profiling and common components and specific weights analysis 下载免费PDF全文
896.
Guerrieri N Scippa S Maietti M de Vincentiis M Cerletti P 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2000,125(4):342-450
Proteolytic activity was studied in the fractionated blood cells of the vanadium accumulating ascidian P. mammillata by separating the cells before measuring their activity. Cells were separated to avoid vanadocyte breakdown and subsequent vanadium diffusion into the assay medium. Our study revealed activity in the morula cell extract that was obtained by sonication and Centricon concentration. After removing part of the extract for enzyme activity assay the remainder was kept at 0 degrees C; it was later found that much of the protein in this latter fraction formed a sediment whereas the protease remained in solution. The serine-protease substrate specificity of the enzyme was measured and the results are discussed in relation to serine protease involvement in immune defense. 相似文献
897.
898.
Aboka FO Yang H de Jonge LP Kerste R van Winden WA van Gulik WM Hoogendijk R Oudshoorn A Heijnen JJ 《Biotechnology and bioengineering》2006,95(6):1032-1042
A mini bioreactor (3.0 mL volume) has been developed and shown to be a versatile tool for rapidly screening and quantifying the response of organisms on environmental perturbations. The mini bioreactor is essentially a plug flow device transformed into a well-mixed reactor by a recycle flow of the broth. The gas and liquid phases are separated by a silicone membrane. Dynamic mass transfer experiments were performed to determine the mass transfer capacities for oxygen and carbon dioxide. The mass transfer coefficients for oxygen and carbon dioxide were found to be 1.55 +/- 0.17 x 10(-5) m/s and 4.52 +/- 0.60 x 10(-6) m/s, respectively. Cultivation experiments with the 3.0 mL bioreactor show that (i) it can maintain biomass in the same physiological state as the 4.0 L lab scale bioreactor, (ii) reproducible perturbation experiments such as changing substrate uptake rate can be readily performed and the physiological response monitored quantitatively in terms of the O2 and CO2 uptake and production rates. 相似文献
899.
Using divergent Giemsa staining protocols designed for other plant species, G-banding was visualized in the chromosomes of Allium cepa L., A. fistulosum L., and their interspecific (A. fistulosum × A. cepa) hybrid. This is the first demonstration of G-banding of Allium chromosomes. Differences and similarities with other Giemsa banding patterns in Allium are discussed. 相似文献
900.
Ptáková Michaela Pokorný Petr Šída Petr Novák Jan Horáček Ivan Juřičková Lucie Meduna Petr Bezděk Aleš Myšková Eva Walls Matthew Poschlod Peter 《Vegetation History and Archaeobotany》2021,30(2):269-286
Vegetation History and Archaeobotany - In a continuous, perfectly stratified sedimentary sequence which was discovered under a large sandstone overhang in northern Bohemia, Czech Republic, we... 相似文献