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51.
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Transgenic tobacco with RuBP-limited photosynthetic assimilationdue to a 95% reduction in phosphoribulokinase activity, hadhigher specific activities of Rubisco in fresh extracts andafter full activation, than in the wild type. Differences inthe amounts of a daytime tight-binding inhibitor were sufficientto contribute significantly to these activity differences. Key words: Nicotiana tabacum, transgenic plant, phosphoribulokinase, Rubisco, tight-binding inhibitor  相似文献   
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Background

Viewed through the micro focus of an interpretive lens, medical anthropology remains mystified because interpretivist explanations seriously downplay the given context in which individual health seeking-behaviours occur. This paper draws upon both the interpretivist and political economy perspectives to reflect on the ethno medical practices within the Korean-Australian community in Sydney.

Methods

We draw on research data collected between 1995 and 1997 for an earlier study of the use of biomedical and traditional medicine by Korean-Australians in Sydney. A total of 120 interviews were conducted with a range of participants, including biomedical doctors, traditional health professionals, Korean community leaders and Korean migrants representing a range of socio-economic backgrounds and migration patterns.

Results and Discussion

First, the paper highlights the extent to which the social location of migrants in a host society alters or restructures their initial cultural practices they bring with them. Second, taking hanbang medicine in the Korean-Australian community as an illustrative case, the paper explores the transformation of the dominant biomedicine in Australia as a result of the influx of ethnomedicine in the era of global capitalism and global movement.

Conclusion

In seeking to explain the popularity and supply of alternative health care, it is important to go beyond the culture of each kind of health care itself and to take into consideration the changes occurring at societal, national and global levels as well as consequential individual response to the changes. New social conditions influence the choice of health care methods, including herbal/alternative medicine, health foods and what are often called New Age therapies.  相似文献   
55.

Background  

It is a well-known phenomenon that some patients with acute left or right hemisphere stroke show a deviation of the eyes (Prévost's sign) and head to one side. Here we investigated whether both right- and left-sided brain lesions may cause this deviation. Moreover, we studied the relationship between this phenomenon and spatial neglect. In contrast to previous studies, we determined not only the discrete presence or absence of eye deviation with the naked eye through clinical inspection, but actually measured the extent of horizontal eye-in-head and head-on-trunk deviation. In further contrast, measurements were performed early after stroke onset (1.5 days on average).  相似文献   
56.
The temporal relationship between embryonic attachment and endometrial vascular permeability was investigated in the gilt. Light and electron microscopy failed to reveal structural differences between Day 10 cycling and pregnant maternal epithelia, including evidence of blastocyst contact. Chorionic adhesion was preserved at mesometrial regions in 3 of 5 Day 13 pregnant animals and appeared to be related to localized differentiation of the underlying maternal epithelium. In order to study uterine vascular permeability, 44 gilts between Days 11 and 19 of the cycle and pregnancy were injected i.v. with a 0.5% solution of Evans Blue (2.5 ml/kg body weight). Examination of excised uteri under ultraviolet light revealed a well-defined zone of endometrial fluorescence corresponding to extravascular content of the dye. Exclusive to pregnant gilts, this response appeared in conjunction with blastocyst elongation at Day 12, and was consistently confined to areas of embryonic membrane contact thereafter. The changes in endometrial morphology and vascular permeability suggest involvement of some embryonic factor(s) acting in a localized manner. Increased histotrophe production is probably facilitated by the flux of plasma constituents to maternal epithelial cells. Coincidence of increased uterine vascular permeability at the site of attachment with elevated blood flow would enhance transport of nutrients toward the conceptus and allow access of blastocyst-induced products to the maternal circulation.  相似文献   
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Using the strictly neutral model as a null hypothesis, we tested for deviations from expected levels of nucleotide polymorphism at the alcohol dehydrogenase locus (Adh-1) within and among four species of pocket gophers (Geomys bursarius major, G. knoxjonesi, G. texensis llanensis, and G. attwateri). The complete protein-encoding region was examined, and 10 unique alleles, representing both electromorphic and cryptic alleles, were used to test hypotheses (e.g., the neutral model) concerning the maintenance of genetic variation. Nineteen variable sites were identified among the 10 alleles examined, including 9 segregating sites occurring in synonymous positions and 10 that were nonsynonymous. Several statistical methods, including those that test for within-species variation as well as those that examine variation within and among species, failed to reject the null hypothesis that variation (both within and between species of Geomys) at the Adh locus is consistent with the neutral theory. However, there was significant heterogeneity in the ratio of polymorphism to divergence across the gene, with polymorphisms clustered in the first half of the coding region and fixed differences clustered in the second half of the gene. Two alternative hypotheses are discussed as possible explanations for this heterogeneity: an old balanced polymorphism in the first half of the gene or a recent selective sweep in the second half of the gene.   相似文献   
59.
Adults of the human parasitic trematode Schistosoma mansoni, which causes hepatosplenic/intestinal complications in humans, synthesize glycoconjugates containing the Lewis x (Lex) Galbeta1-->4(Fucalpha1-- >3)GlcNAcbeta1-->R, but not sialyl Lewis x (sLex), antigen. We now report on our analyses of Lexand sLexexpression in S.haematobium and S.japonicum, which are two other major species of human schistosomes that cause disease, and the possible autoimmunity to these antigens in infected individuals. Antigen expression was evaluated by both ELISA and Western blot analyses of detergent extracts of parasites using monoclonal antibodies. Several high molecular weight glycoproteins in both S. haematobium and S. japonicum contain the Lexantigen, but no sialyl Lexantigen was detected. In addition, sera from humans and rodents infected with S.haematobium and S.japonicum contain antibodies reactive with Lex. These results led us to investigate whether Lexantigens are expressed in other helminths, including the parasitic trematode Fasciola hepatica , the parasitic nematode Dirofilaria immitis (dog heartworm), the ruminant nematode Haemonchus contortus , and the free-living nematode Caenorhabditis elegans . Neither Lexnor sialyl-Lexis detectable in these other helminths. Furthermore, none of the helminths, including schistosomes, express Lea, Leb, Ley, or the H- type 1 antigen. However, several glycoproteins from all helminths analyzed are bound by Lotus tetragonolobus agglutinin , which binds Fucalpha1-->3GlcNAc, and Wisteria floribunda agglutinin, which binds GalNAcbeta1-->4GlcNAc (lacdiNAc or LDN). Thus, schistosomes may be unique among helminths in expressing the Lexantigen, whereas many different helminths may express alpha1,3-fucosylated glycans and the LDN motif.   相似文献   
60.
The selectins interact in important normal and pathological situations with certain sialylated, fucosylated glycoconjugate ligands containing sialyl Lewisx(Neu5Acalpha2-3Galbeta1-4(Fucalpha1-3)GlcN Ac). Much effort has gone into the synthesis of sialylated and sulfated Lewisxanalogs as competitive ligands for the selectins. Since the natural selectin ligands GlyCAM-1 and PSGL-1 carry sialyl Lewisxas part of a branched Core 2 O-linked structure, we recently synthesized Galbeta1-4(Fucalpha1-3)GlcNAcbeta1-6(SE-3Galbeta1++ +-3)GalNAc1alphaOMe and found it to be a moderately superior ligand for L and P-selectin (Koenig et al. , Glycobiology 7, 79-93, 1997). Other studies have shown that sulfate esters can replace sialic acid in some selectin ligands (Yeun et al. , Biochemistry, 31, 9126-9131, 1992; Imai et al. , Nature, 361, 555, 1993). Based upon these observations, we hypothesized that Neu5Acalpha2-3Galbeta1-3GalNAc might have the capability of interacting with L- and P-selectin. To examine this hypothesis, we synthesized Galbeta1-4(Fucalpha1-3)GlcNAcbeta1-6(Neu5Acalpha2++ +-3Galbeta1-3)- GalNAc alpha1-OB, which was found to be 2- to 3-fold better than sialyl Lexfor P and L selectin, respectively. We also report the synthesis of an unusual structure GalNAcbeta1-4(Fucalpha1- 3)GlcNAcbeta1-OMe (GalNAc- Lewisx-O-methyl glycoside), which also proved to be a better inhibitor of L- and P-selectin than sialyl Lewisx-OMe. Combining this with our knowledge of Core 2 branched structures, we have synthesized a molecule that is 5- to 6-fold better at inhibiting L- and P-selectin than sialyl Lewisx-OMe, By contrast to unbranched structures, substitution of a sulfate ester group for a sialic acid residue in such a molecule resulted in a considerable loss of inhibition ability. Thus, the combination of a sialic acid residue on the primary (beta1-3) arm, and a modified Lexunit on the branched (beta1-6) arm on an O-linked Core 2 structure generated a monovalent synthetic oliogosaccharide inhibitor superior to SLexfor both L- and P-selectin.   相似文献   
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