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971.
Returning research results to participants is recognised as an obligation that researchers should always try to fulfil. But can we ascribe the same obligation to researchers who conduct genomics research producing only aggregated findings? And what about genomics research conducted in developing countries? This paper considers Beskow's et al. argument that aggregated findings should also be returned to research participants. This recommendation is examined in the context of genomics research conducted in developing countries. The risks and benefits of attempting such an exercise are identified, and suggestions on ways to avoid some of the challenges are proposed. I argue that disseminating the findings of genomic research to participating communities should be seen as sharing knowledge rather than returning results. Calling the dissemination of aggregate, population level information returning results can be confusing and misleading as participants might expect to receive individual level information. Talking about sharing knowledge is a more appropriate way of expressing and communicating the outcome of population genomic research. Considering the knowledge produced by genomics research a worthwhile output that should be shared with the participants and approaching the exercise as a ‘sharing of knowledge’, could help mitigate the risks of unrealistic expectations and misunderstanding of findings, whilst promoting trusting and long lasting relationships with the participating communities.  相似文献   
972.
Poor medical waste treatment is common practice in most developing countries where on-site sub-standard incineration is common. Potentially hazardous substances such as polychlorinated dioxins and dibenzofurans and polycyclic aromatic hydrocarbons have been detected in gaseous emissions as well as bottom ash generated by the said process. There is also evidence on the emission of potentially toxic trace metals such as lead and cadmium as well as speculations on the release of brominated dioxins and dibenzofurans. The presence of residential areas within the vicinity of these sites increases human susceptibility to various health risks. This eventually necessitates the development of efficient risk assessment tools such as a site conceptual model that can adequately facilitate data collection activities and the estimation of health risks.  相似文献   
973.
Mitochondrial anti-apoptotic Bcl2 and BclxL proteins, are overexpressed in multiple tumour types, and has been involved in the progression and survival of malignant cells. Therefore, inhibition of such proteins has become a validated and attractive target for anticancer drug discovery. In this manner, the present studies developed a series of novel isatin–indole conjugates (7a-j and 9a-e) as potential anticancer Bcl2 and BclxL inhibitors. The progression of the two examined colorectal cancer cell lines was significantly inhibited by all of the prepared compounds with IC50 ranges132–611 nM compared to IC50 = 4.6 µM for 5FU, against HT-29 and IC50 ranges 37–468 nM compared to IC50 = 1.5 µM for 5FU, against SW-620. Thereafter, compounds 7c and 7g were selected for further investigations. Interestingly, both compounds exhibited selective cytotoxicity against both cell lines with high safety to normal fibroblast (HFF-1). In addition, both compounds 7c and 7g induced apoptosis and inhibited Bcl2 and BclxL expression in a dose-dependent manner. Collectively, the high potency and selective cytotoxicity suggested that conjugates 7c and 7g could be a starting point for further optimisation to develop novel pro-apoptotic and antitumor agents towards colon cancer.  相似文献   
974.
Abstract

The endemic New Zealand genus Neolimnia is redescribed, and a key is given to the 14 species now included. Four new species are described - Neolimnia raiti, N. pepekeiti, N. ura, and N. repo. Two new synonymies are proposed; N. ocellata Tonnoir &; Malloch with N. castanea (Hutton); and N. dubiosa Tonnoir &; Malloch with N. irrorata Tonnoir &; Malloch. Lectotypes are designated for N. tranquilla (Hutton), N. castanea (Hutton), N. obscura (Hutton), and N. striata (Hutton). Male postabdomens of all species are illustrated. Character variation and generic, subgeneric, and species relationships are discussed briefly.  相似文献   
975.
Evidence of an atmospheric CO2 fertilization effect on radial growth rates was uncovered by examining climate–growth relationships for seven western juniper tree‐ring chronologies in central Oregon using multiple regression models. Consistent upward trends of the residuals from dendroclimatic models indicated a decreased ability for climate parameters to predict growth with time. Additionally, an assessment was made of whether enhanced growth was detectable under drought conditions, because a major benefit of elevated atmospheric CO2 is the reduction of water stress. Mean ring indices were compared between ecologically comparable drought years, when atmospheric CO2 was lower (1896–1949), and more recent drought years that occurred under higher atmospheric CO2 concentrations (1950–96/98). The results presented herein show that: (i) residuals from climate/growth models had a significant positive trend at six of seven sites, suggesting the presence of a nonclimatic factor causing increased growth during recent decades; (ii) overall growth was 23% greater in the latter half of the 20th century; (iii) growth indices during matched drought and matched wet years were 63% and 30% greater, respectively, in the later 20th century than the earlier 20th century; and (iv) harsher sites had greater responses during drought periods between early and late periods. While it is not possible to rule out other factors, these results are consistent with expectations for CO2 fertilization effects.  相似文献   
976.
977.
978.
Biometrical variability of foliage, cones, and seeds were analyzed in 8 native populations (throughout the range) of a relictual species,Cupressus bakeri Jeps. (Cupressaceae) from California and Oregon. The partition of variation within and among populations for this rare plant was investigated and the justification for subspecies status was reviewed. Morphological characters varied significantly, with more of the variation among populations than at the population level. Multivariate analyses indicated close affinities among populations on serpentine sites suggesting the presence of a serpentine race. However, the high degree of variation among populations did not permit their clear separation into the two subspecies described byWolf (1948). We conclude thatC. bakeri should be treated as a monotypic species.  相似文献   
979.
Preparation of samples for sodium dodecyl sulphate polyacrylamide gel electrophoresis routinely involves heating the protein in solution containing detergent and reducing agent for at least two minutes. Here we show that this treatment causes fragmentation of the protein glycogen phosphorylase, whether purified or as a component of a skeletal muscle preparation. The fragments are detected as minor bands on western blots and represent the products of discrete breakage point in the peptide sequence. Protease inhibitors cannot suppress the fragmentation.Such small amounts of immunoreactive fragments may be incorrectly identified on western blots as contaminants that were originally present in the antigen preparation. They may also be a source of ambiguity in studies that search for degradation intermediates during proteolysis.  相似文献   
980.
We censused gorilla populations in northern Congo from February to April 1989 and June 1990. The objective was to provide the first quantitative data from a variety of sites on gorilla populations from a country that had unknown but potentially high populations. The method used was a census of nests along strip transects. A total of 401.0 km of transects was sampled in four different study areas. The overall density calculated for all transects was 0.4 nesting gorillas/km2. The highest density, 1.2 nesting gorillas/km2, was found in the vast Likouala swamp area of north central Congo. The two northern sites showed low densities of 0.1 and 0.2 nesting gorillas/km2, respectively. The northwestern site showed an intermediate density of 0.6 nesting gorillas/km2. The vegetation type with the highest density was swamp forest with 2.4 nesting gorillas/km2. The limited sample presented shows that gorillas are widespread and common in northern Congo, even in the swamp forests previously considered unsuitable as gorilla habitat. It is probable that Congo holds the largest population of gorillas in Africa after Gabon. © 1992 Wiley-Liss, Inc.  相似文献   
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