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991.
992.
A quantitative study of the fecal flora was carried out in 21 neonates with necrotizing enterocolitis (NEC), (4 infants being born at term) and 57 control infants (30 born at term and 27 born before term). In the population as a whole Klebsiella was detected more frequently in NEC than in the controls. This was especially true in premature infants where Klebsiella was found in 65% of the affected infants versus 33% of the controls (p less than 0,05), while no Klebsiella was detected in the 4 term infants with NEC and in 87% of the term controls. These data suggest that Klebsiella could play a role in the pathogenesis of NEC, especially in the premature infant. Therefore, it seems required to avoid the artificial selection of Klebsiella in the neonate.  相似文献   
993.
Some now seemingly bizarre childbirth practices of the Middle Ages, such as "child-breaking," baptism in utero, excessive modesty, and use of the obstetric chair and tools, are described. Also outlined are the slow, painful steps in the climb out of these dark times: education for midwives, permitting the male in the lying-in room, aseptic technique, und the use of anesthesia.  相似文献   
994.
Synthesis and antiparasitic activity vs T. cruzi and L. donovani of a series of 9-thioaryl acridines are reported. A convenient correlation between molecular structure and biological activity is proposed. Results not only agree with the classical interactions of acridines with DNA but also suggest possible role of charge transfer complexes.  相似文献   
995.
The synthesis of several acridinic thioethers is described. Compounds prepared were tested in vitro as potential drugs against the opportunistic infection known as cryptosporidiosis. With a view to predict activity, the quantitative structure-activity relationships were investigated. Correlations between experimental data and either log P or pKa are discussed.  相似文献   
996.
Cross sectional data reporting the height, weight, and body mass index of UK patients with cystic fibrosis are presented. During the first decade of life height and weight in patients with cystic fibrosis are maintained at about 0.5 SD below those of the general population, which reflects an improvement over earlier published observations. Postpubertal stature and weight maintenance in the cystic fibrosis population still show substantial deficits which may be related to treatment.  相似文献   
997.
Summary This electron microscopic study, based on serial section analysis, describes the synaptic organization of the interstitial subnucleus of the nucleus of the solitary tract and identifies the terminals of the vagal primary afferents utilizing degeneration and HRP transport. The interstitial subnucleus contains sparsely scattered cell bodies, numerous dendrites and axon terminals, and bundles of unmyelinated and myelinated axons. The cell bodies which are small in diameter have an organelle poor cytoplasm and a large invaginated nucleus.Axon terminals can be classified into two main types according to their vesicular shape. The first type contains clear, round vesicles and can be further subdivided into two subgroups on the basis of their morphology and the size of their vesicles. In the first subgroup the terminals are small, contain a few mitochondria and their vesicles are densely packed with an homogeneous size. In the second subgroup the terminals which vary from small to large, contain many mitochondria and contain round vesicles which are heterogeneous in size. The second main terminal type consists of axon terminals containing pleomorphic vesicles which are associated with asymmetrical or symmetrical synaptic contacts on dendrites. Axo-axonic contacts are present in the interstitial subnucleus. In general, the presynaptic axon terminals contain pleomorphic vesicles and the postsynaptic elements contain round vesicles of varying size. In some dendrites, identified by the presence of ribosomes, groups of round and/or pleomorphic vesicles are found associated with synaptic contacts. These dendrites are presynaptic to conventional dendrites and postsynaptic to axon terminals. After removal of the nodose ganglion, degenerative alterations are seen only at the caudal and middle levels of the interstitial subnucleus. Degeneration occurs in a few myelinated axons and in axon terminals which usually contain a mixture of small and larger round, clear vesicles. After HRP injection into the vagus nerve, the HRP reaction product is visible in axon terminals filled with clear, round vesicles which are heterogeneous in size. The labelled axon terminals establish single or multiple synaptic contacts.This study demonstrates that terminals of vagal primary afferents consist principally of terminals of the second subgroup. The morphology of these terminals are compared to primary afferents in the brainstem and spinal cord.  相似文献   
998.
999.
Cerebral malaria is probably related to an overstimulation of the immune system and the cytokine network. We have previously demonstrated that tumour necrosis factor (TNF) secretion by human macrophages can be induced by soluble and heat-stable malarial antigens. Indirect evidence from epidemiological and in vitro studies suggests that Pf155/RESA can be considered as a candidate for triggering TNF secretion. Thus we conducted experiments to investigate the relationship between Pf155/RESA and TNF production. The SGE1 strain of Plasmodium falciparum was compared with the P. falciparum FCR3 strain, which does not express Pf155/RESA protein, for ability to induce TNF secretion by normal human macrophages in vitro. Synthetic peptides from the Pf155/RESA antigen ((EENV)4, (EENVEHDA)4, (DDEHVEEPTVA)3), were used in some experiments. TNF levels were measured by an immunoradiometric assay. We observed that the RESA-defective strain induces lower levels of TNF after schizont rupture than the SGE1 strain. Moreover, substantial TNF secretion was detected when macrophages were incubated with all three peptides, maximum levels being obtained with the (EENV)4 peptide. Although previous reports have described TNF-inducing activity of phospholipid from P. falciparum, these findings strengthen the evidence for Pf155/RESA antigens also being involved in TNF production during malaria.  相似文献   
1000.
A considerable fraction of life develops in the sea at temperatures lower than 15 degrees C. Little is known about the adaptive features selected under those conditions. We present the analysis of the genome sequence of the fast growing Antarctica bacterium Pseudoalteromonas haloplanktis TAC125. We find that it copes with the increased solubility of oxygen at low temperature by multiplying dioxygen scavenging while deleting whole pathways producing reactive oxygen species. Dioxygen-consuming lipid desaturases achieve both protection against oxygen and synthesis of lipids making the membrane fluid. A remarkable strategy for avoidance of reactive oxygen species generation is developed by P. haloplanktis, with elimination of the ubiquitous molybdopterin-dependent metabolism. The P. haloplanktis proteome reveals a concerted amino acid usage bias specific to psychrophiles, consistently appearing apt to accommodate asparagine, a residue prone to make proteins age. Adding to its originality, P. haloplanktis further differs from its marine counterparts with recruitment of a plasmid origin of replication for its second chromosome.  相似文献   
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