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41.
Expression of the adhesion molecules, ICAM-1, VCAM-1, NCAM, CD44, CD49d (VLA-4, a chain), and CDlla (LFA-1, a chain) on mouse oocytes, and pre- and peri-implantation stage embryos was examined by quantitative indirect immunofluorescence microscopy. ICAM-1 was most strongly expressed at the oocyte stage, gradually declining almost to undetectable levels by the expanded blastocyst stage. NCAM, also expressed maximally on the oocyte, declined to undetectable levels beyond the morula stage. On the other hand, CD44 declined from highest expression at the oocyte stage to show a second maximum at the compacted 8-cell/morula. This molecule exhibited high expression around contact areas between trophecto-derm and zona pellucida during blastocyst hatching. CD49d was highly expressed in the oocyte, remained significantly expressed throughout and after blastocyst hatching was expressed on the polar trophecto-derm. Like CD44, CD49d declined to undetectable levels at the blastocyst outgrowth stage. Expression of both  相似文献   
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Animal-assisted therapy (AAT) has been used in a variety of healthcare settings and studies to evaluate the potential patient benefits are warranted. This retrospective study measured the impact of AAT on the use of oral pain medications by adults after total joint replacement surgery. One group of patients received care in a hospital with an AAT program and the comparison group was in a hospital without an AAT program. Adult patient cohorts were matched on: age, gender, ethnicity, length of stay, and Diagnosis Related Group code for type of total joint replacement. Pain medication doses, converted into morphine equivalent daily doses (MEDD), were compared. Pain medication use was significantly less in the AAT group: 15.32 mg vs. 21.16 (t(119) = 2.72, p = 0.007). The effectiveness of AAT in decreasing the need for pain medication and its effect on patient well-being in the post-operative period and in other settings deserves further study.  相似文献   
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Computer simulations are developed and employed to examine the expected temporal distributions of nodes under a null model of stochastic lineage bifurcation and extinction. These Markovian models of phylogenetic process were constructed so as to permit direct comparisons against empirical phylogenetic trees generated from molecular or other information available solely from extant species. For replicate simulated phylads with n extant species, cumulative distribution functions (cdf's) of branching times were calculated, and compared (using the Kolmogorov-Smirnov test statistic D) to those from three published empirical trees. Molecular phylogenies for columbine plants and avian cranes showed statistically significant departures from the null expectations, in directions indicating recent and ancient species' radiations, respectively, whereas a molecular phylogeny for the Drosophila virilis species group showed no apparent historical clustering of branching events. Effects of outgroup choice and phylogenetic frame of reference were investigated for the columbines and found to have a predictable influence on the types of conclusions to be drawn from such analyses. To enable other investigators to statistically test for nonrandomness in temporal cladogenetic pattern in empirical trees generated from data on extant species, we present tables of mean cdf's and associated probabilities under the null model for expected branching times in phylads of varying size. The approaches developed in this report complement and extend those of other recent methods for employing null models to assess the statistical significance of pattern in evolutionary trees.   相似文献   
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We conducted a study to review the consenting process in a vaginal Microbicide feasibility study conducted in Mazabuka, Zambia. Participants were drawn from those participating in the microbicide study. A questionnaire and focus group discussion were used to collect information on participants understanding of study aims, risks and benefits. Altogether, 200 participants took part in this study. The results of the study showed that while all participants signed or endorsed their thumbprints to the consent forms, full informed consent was not attained from most of the participants since 77% (n = 154) of the participants had numerous questions about the study and 34% (n = 68) did not know who to get in touch with concerning the study. Study objectives were not fully understood by over 61% of the participants. Sixty four percent of the participants were not sure of the risks of taking part in the microbicide study. A significant number thought the study was all about determining their HIV status. Some participants were concerned that their partners were not on the trial as they were convinced that being on the study meant that that they had a lifetime protection from HIV infection. The process of obtaining consent was inadequate as various phases of the study were not fully understood. We recommend the need for researchers to reinforce the consenting process in all studies and more so when studies are conducted in low literacy populations.  相似文献   
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A novel approach for chromosome doubling that consists of treating embryos instead of parts of micropropagated plants was investigated. Following 2-year trials, amiprofos-methyl (APM) was found to be superior to oryzalin on the basis of a lower toxicity, and we were able to narrow the range of concentrations of APM. The addition of 2% dimethyl sulphoxide (DMSO) and 1% Triton X-100 to 25 microM APM had no effect in all treatments. A final experiment with 6,658 embryos demonstrated that a 2-day treatment in liquid media supplemented with 50 microM APM was the most successful with respect to chromosome doubling-36.7% of the plants were diploid-but the survival rate was reduced to 52.5% of that of the non-treated control. A 2-day treatment in liquid medium supplemented with 25 microM APM or a 2-day treatment on solid medium with 50 microM APM resulted in the production of diploids at a frequency of 28.9% and 21.3%, respectively. These may represent alternative methods for chromosome doubling since compared to the untreated control these two treatments reduced the survival rate by only about 24%. Final ploidy and fertility of the large proportion of induced mixoploid plants (up to 30.3%) need to be evaluated in further studies.  相似文献   
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