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611.
Marine Biotechnology - The inorganic part of marine sponges, called Biosilica (BS), presents an osteogenic potential and the ability of consolidating fractures. Moreover, 3D printing technique is...  相似文献   
612.
Probiotics and Antimicrobial Proteins - As of recent, the pandemic episode of COVID-19, a severe acute respiratory syndrome brought about by a novel coronavirus (SARS-CoV-2) expanding the pace of...  相似文献   
613.
Breast deformities following conservative cancer surgery are seen with increasing frequency and often represent difficult reconstructive problems. Type II deformities are characterized by localized tissue insufficiency, which can be due to skin insufficiency (type IIa), subcutaneous tissue insufficiency (type IIb), or both (type IIab). Correction of a locally damaged breast is a surgical challenge that can result in a fully restored breast if selection of the surgical procedure is properly carried out. A series of 37 patients who underwent correction of type II deformities from 1980 to 1989 was reviewed. Results obtained with different surgical procedures, including simple submuscular placement of traditional or expandable implants, breast reshaping, transposition of a latissimus dorsi muscle or musculocutaneous flap, TRAM flap, and reverse abdominoplasty, were evaluated. Aesthetic outcome was judged to be good or excellent in 78 percent of patients. Guidelines for selection of the most appropriate surgical procedure according to the defect's etiology, morphology, and location and to the breast's size and shape are presented.  相似文献   
614.
We examined the extent of variation of the 3' region of the circumsporozoite gene among Plasmodium falciparum isolates through amplification of a selected DNA fragment followed by DNA sequencing. A total of 32 isolates were analyzed, of which 24 were from Amazon endemic areas in Brazil and 8 from widely separated geographical regions in the world. Among Brazilian isolates only 2 variants were detected: 19 displayed the same sequence of strain 7G8 whereas the 4 remaining isolates differed from the 7G8 strain at five nucleotide positions which also led to amino acid changes. Variation was restricted to one of the T-helper epitopes while the sequence identified as a cytotoxic T cell epitope was conserved in all Brazilian isolates. P. falciparum samples from other geographical regions in the world showed sequences distinct from those of Brazilian isolates. However, some constancy could be observed within that variation. For instance, the most frequent nucleotide substitutions, from A and C at nucleotide positions 1015 and 1024, were the same in all isolates.  相似文献   
615.
The extent to which genome sizes and other nucleotypic factors influence the phyletic diversification of lineages has long been discussed but remains largely unresolved. In the present work, we present evidence that the genomes of at least 16 species of the neotropical rivulid killifish genus Austrolebias are unusually large, with an average DNA content of about 5.95 ± 0.45 picograms per diploid cell (mean C-value of about 2.98 pg). They are thus larger than the genomes of very nearly all other diploid, i.e. non-(paleo) polyploid species of actinopterygian fishes so far reported. Austrolebias species appear to be conventional diploids in all other respects and there is no reason to believe that they arise from polyploid ancestors. The genome sizes reported for other rivulid killifishes, including a putative sister group, are considerably smaller and fall within the range typical of most other cyprinodontoid species. Therefore, it appears that the ancestor(s) of contemporary Austrolebias have undergone one or more episodes of genome expansion encompassing sudden speciation process during the Pleistocene. In addition, these findings are consistent with the hypothesis of a positive correlation between species richness and genome size.  相似文献   
616.
Despite the great poverty in the village of Doria, (Dhaka, Bangladesh) it is religious conflicts, and not class conflict, which has become important. The poor in each religious group are made pawns in the competition between wealthy families of different religious groups. In this paper I use the example of a thief-searching ritual, as an element of interconnected ‘social situations’, to illustrate the conflict and cooperation characterising inter- and intra-group relationships in Doria. It shows how a ritual is ‘rediscovered’ and used by religious leaders to achieve instrumental and expressive/ normative ends.  相似文献   
617.
618.
We have automated the trityl-on purification of oligonucleotides by use of an XYZ axis robotic solid-phase extraction system. This greatly decreased the preparation time required for oligonucleotide purification. After about 15 min for set up of the samples and instrument, the oligonucleotides are automatically purified with a 15-min run time per sample. Thus, for example, the purification of 15 oligonucleotides requires only about 15 min of preparation time and 4 h of machine time. Yields and purity are equivalent to manual methods.  相似文献   
619.
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