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551.
The structure and nucleotide sequence of the murine lactotransferrin-encoding gene (LTF) deduced partly by direct sequencing of genomic clones in the λ phage vector and partly by enzymatic amplification of genomic DNA segments primed with the oligodeoxyribonucleic primers homologous to the cDNA sequence. The λ phage clones contained the 5′ half of the gene corresponding to the first eight exons and an incomplete ninth exon interrupted by eight introns. Genomic clones corresponding to the 3′ half of the LTF gene could not be obtained on repeated attempts from two different mouse genomic libraries, suggesting the possible presence of unclonable sequences in this part of the gene. Hence, PCR was used to clone the rest of the gene. Four out of the presumed eight remaining introns were cloned along with the flanking exons using PCR. Comparison of the structure of the LTF gene with those of the two other known transferrin-encoding genes, human serum transferrin-encoding gene and chicken ovotransferrin-encoding gene reveals that all three genes have a very similar intron-exon distribution pattern. The hypothesis that the present-day transferrin-encoding genes have originated from duplication of a common ancestral gene is confirmed here at the gene level. An interesting finding is the identification of a region of shared nucleotides between the 5′ flanking regions of the murine LTF and myeloperoxidase-encoding genes, the two genes expressed specifically in neutrophilic granulocytes. 相似文献
552.
Patrick W. Tank 《Developmental biology》1977,57(1):15-32
The timing of morphogenetic events in the regenerating forelimb of the axolotl was investigated by rotation of limb coverings at well-defined stages in the regenerative process. Both the skin covering the stump and the epidermis covering the regenerate were manipulated independently and together as a unit. The results show that the transmission of morphogenetic information covers a broad range of regenerative stages. This morphogenetic information seems first to become irreversibly fixed in the regenerate by the stage of late bud. The regenerate is sensitive to stump influences at early stages of regeneration, but it becomes insensitive to stump influences by the stage of palette. Evidence is presented which implies that epidermis that covers the regenerate is capable of influencing morphogenesis. 相似文献
553.
Vince P. Palace Michael F. Hill Neelam Khaper Pawan K. Singal 《Free radical biology & medicine》1999,26(11-12):1501-1507
The supply of vitamin A to the myocardium by storage organs during increased oxidative stress subsequent to myocardial infarction (MI) was examined in hemodynamically assessed rats using compartment analysis of a radio-labeled vitamin A. 3H-Vitamin A was injected into two groups of rats: an MI group and a control group. There were no differences in the plasma or myocardial content of total vitamin A (unlabeled + labeled) between the two groups. However, the proportion of 3H-vitamin A was greater in the myocardium as well as plasma of MI rats. Rats with MI also had significantly lower 3H-vitamin A levels in liver and kidney than sham controls. The greatest difference in vitamin A content was in the concentrations of 3H-labeled storage forms of vitamin A in the liver of MI animals. Activity of bile salt-dependent retinyl ester hydrolase, an enzyme responsible for hydrolyzing vitamin A storage forms, was significantly increased in the liver of MI animals. These data indicate that analysis of plasma concentrations of vitamin A to ascertain links to cardiac conditions may be inappropriate. Specifically, during MI, increased amounts of vitamin A are mobilized from the liver to the heart without changing plasma concentrations. This is facilitated by an increase in the activity of an enzyme that hydrolyzes vitamin A storage forms. 相似文献
554.
Mixtalol (a mixture of long chain aliphatic alcohols varying in chain length from C24 to C32) applied to Brassica juncea plants as foliar spray caused an increase in secondary and tertiary branching with consequent enhancement in seed yield through increased number of inflorescences and siliquae per plant. The percentage of immature siliquae and shattering of siliquae decreased with this treatment. Mixtalol increased total dry matter of plants, partitioning coefficient and harvest index. The contents of starch, protein and oil were also higher in seeds from Mixtalol treated plants. 相似文献
555.
Richard G A Feachem Neelam K Sekhri Karen L White 《BMJ (Clinical research ed.)》2002,324(7330):135-143
ObjectiveTo compare the costs and performance of the NHS with those of an integrated system for financing and delivery health services (Kaiser Permanente) in California.MethodsThe adjusted costs of the two systems and their performance were compared with respect to inputs, use, access to services, responsiveness, and limited quality indicators.ResultsThe per capita costs of the two systems, adjusted for differences in benefits, special activities, population characteristics, and the cost environment, were similar to within 10%. Some aspects of performance differed. In particular, Kaiser members experience more comprehensive and convenient primary care services and much more rapid access to specialist services and hospital admissions. Age adjusted rates of use of acute hospital services in Kaiser were one third of those in the NHS.ConclusionsThe widely held beliefs that the NHS is efficient and that poor performance in certain areas is largely explained by underinvestment are not supported by this analysis. Kaiser achieved better performance at roughly the same cost as the NHS because of integration throughout the system, efficient management of hospital use, the benefits of competition, and greater investment in information technology.
What is already known on this topic
Comparisons of healthcare systems in different countries have to be undertaken with great care but can be instructiveThe overall healthcare system in the United States is more expensive than the NHS and population health outcomes are no betterThe US healthcare system comprises many discrete and unique subsystems, including the health maintenance organisationsWhat this paper adds
An integrated, non-profit health maintenance organisation in California (Kaiser Permanente), with over six million members, costs about the same as the NHS but performs considerably betterKaiser''s superior performance is mainly in prompt and appropriate diagnosis and treatmentThese findings challenge the widely held view that the NHS is efficient and that its inadequacies are mainly due to underinvestment 相似文献556.
Faria Fatima Neelam Pathak Deepti Srivastava Smita Rastogi Verma 《Geomicrobiology journal》2021,38(1):29-35
Abstract Phosphorous (P) that upholds life become unattainable as most of them become unavailable due to the formation of insoluble complexes with cations such as Ca2+, Al3+ and Fe3+ forming a complex calcium phosphate (Ca3(PO4)2), aluminum phosphate (AlPO) and ferrous phosphate (FePO) that results in the decrease of soluble P to a greater extent. There are several reports stating that several rhizospheric fungal species play an important role in solubilizing these insoluble phosphates into a soluble form by the excretion of enzymes like phosphatase, phytase enzymes, and organic acids. In view of this, so we have collected twenty fungal isolates having probable phosphate solubilizing efficiency from different regions of Lucknow, India. Their morphological and biochemical characteristics were tested. Among all, six efficient fungal isolates were further checked at molecular level by using 18S rRNA universal primers and by RAPD means. A dendrogram indicated 40-90% homology i.e., highest similarity was found in between species of Aspergillus flavus and A. biplanus with 33.8% similarity while minimum similarity was observed among A. flavus and Fusarium oxysporum. These findings suggest RAPD proves as, a reliable molecular tool that helps in strain specific discrimination. 相似文献