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991.
Size-dependent exclusion of macromolecules from gel matrices has long been discussed in terms of pore models. An alternate approach is to calculate the partition coefficient of the distributed species between the matrix material and the mobile phase assuming that the gel can be treated as a polymer solution of appropriate concentration and molecular weight. This approach is particularly appealing in attempting to predict the behaviour of 'tentacle' phases in which the matrix contains anchored linear neutral polymers. The mean field theory of polymer solution is used to predict K, the partition coefficient of a polymer molecule distributing between the gel and mobile phases. The reduction in entropy suffered by the macromolecule in the gel phase is sufficient to produce an exponential dependence of K on the molecular weight of the partitioning species. The enthalpy of interaction between the gel polymer and the distributed species provides a parameter which describes the specificity or recognition in the interaction. The predicted linear dependence of in K on protein molecular weight is satisfactorily borne out by a data set on eight standard proteins chromatographed on four separate gel types. 相似文献
992.
MK Popkin AL Callies EA Colón RD Lentz DE Sutherland 《Canadian Metallurgical Quarterly》1993,34(3):251-258
To examine the role of psychiatric diagnosis in the surgical outcome of pancreas transplantation, we studied candidates with type I diabetes mellitus. Eighty of 140 candidates underwent transplantation. Survival analysis found the extent of human leukocyte antigen-DR (HLA-DR) matching, two diagnoses, and patients' perceived support from first-degree relatives to be related to duration of full-graft function. Lifetime diagnoses of tobacco use disorder (P = 0.029) and alcohol abuse/dependence (P = 0.006) were associated with less favorable outcomes; perceived support was associated with positive outcomes (P = 0.048). Subsequent analysis suggested that the four variables independently and directly affect outcome. 相似文献
993.
The paper reviews the epidemiological studies that investigate the relationships between dietary protein intake and the risk of some cancer and that have been published since 1980. A comparison of these reports is complicated because of many confounding factors that could obscure the conclusions (e.g. choice of controls) and because it is difficult to distinguish the consumption of fat from that of animal proteins. The 75 examined publications deal with the influence of food intake on different cancers: colo-rectal (42), stomach (8), breast (7), ovarian (4), endometrium (3), prostate (4), pancreas (2), urothelium (1), bladder (2), brain (1), lymphoma (1). From these studies in parallel with information from other sources, it is concluded that pyrolysis products generated by heat treatment of protein-rich food could be responsible factors for, at least, colo-rectal cancer. 相似文献
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995.
VJ Watts CP Lawler AJ Gonzales QY Zhou O Civelli DE Nichols RB Mailman 《Canadian Metallurgical Quarterly》1995,21(2):177-187
Anti-nitric oxide synthase antibody was used to study the distribution, cytoarchitecture, and synaptic relations of nitric oxide synthase-like immunoreactive neurons in the whole rostral-caudal length of the dorsal raphe nucleus of the rat and compared them with serotonergic neurons. Results showed that the distribution of the nitric oxide synthase in the dorsal raphe nucleus was similar to that of the serotonergic neurons at the rostral part of the dorsal raphe nucleus, including the mediodorsal and the medioventral cell groups, and changed at the middle and caudal parts of the dorsal raphe nucleus. The cytoarchitecture of the nitric oxide synthase-like immunoreactive neurons in the medioventral cell group of the dorsal raphe nucleus was similar to that of the serotonergic neurons. Similar to the serotonergic neurons there, nitric oxide synthase-like immunoreactive neurons also received synapses from axon terminals that contained round, or flattened vesicles, or both kinds. Different to the serotonergic neurons, the few nitric oxide synthase-like immunoreactive axon terminals that were in this area formed synapses. 相似文献
996.
D Guenzburger DE Ellis PA Montano GK Shenoy SK Malik DG Hinks P Vaishnava CW Kimball 《Canadian Metallurgical Quarterly》1985,32(7):4398-4409
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999.
The odd-skipped (odd) gene, which was identified on the basis of a pair-rule segmentation phenotype in mutant embryos, is initially expressed in the Drosophila embryo in seven pair-rule stripes, but later exhibits a segment polarity-like pattern for which no phenotypic correlate is apparent. We have molecularly characterized two embryonically expressed odd-cognate genes, sob and bowel (bowl), that encode proteins with highly conserved C2H2 zinc fingers. While the Sob and Bowl proteins each contain five tandem fingers, the Odd protein lacks a fifth (C-terminal) finger and is also less conserved among the four common fingers. Reminiscent of many segmentation gene paralogues, the closely linked odd and sob genes are expressed during embryogenesis in similar striped patterns; in contrast, the less-tightly linked bowl gene is expressed in a distinctly different pattern at the termini of the early embryo. Although our results indicate that odd and sob are more likely than bowl to share overlapping developmental roles, some functional divergence between the Odd and Sob proteins is suggested by the absence of homology outside the zinc fingers, and also by amino acid substitutions in the Odd zinc fingers at positions that appear to be constrained in Sob and Bowl 相似文献
1000.
L Papke J McCardell L Moeser SK Guzelaydin D Holk DE Arnaut 《Canadian Metallurgical Quarterly》1996,19(4):211-215
Growing interest in peripherally inserted intravenous catheters led to the development of the PICC Council. This council was established to provide a resource of information for the area nurses involved in peripherally inserted intravenous catheters use and care. The group went through various developmental stages as they sought to establish cohesiveness and professional collaboration across a variety of practice settings. The outcome was the development of recommendations for vocabulary, communication, and care/maintenance activities, that could be used by intravenous nurses to enhance patient care coordination. 相似文献