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101.
Effects of boron and calcium on the blue-green algaCalothrix parietina were determined. There was a significant decrease in growth, chlorophylla, saccharide and total nitrogen fixed under Ca2+ and boron deficiency. The addition of boron at different concentrations to Ca2+-deficient cultures led to partial recovery of these parameters. Calcium addition to B-deficient cells led to a partial recovery
of growth, saccharide, chlorophylla and total nitrogen fixed. At high concentrations of calcium these parameters were significantly inhibited. The data also
revealed that the different responses to B concentrations were due to the Ca2+ level in the medium. 相似文献
102.
The non-secretory ameloblasts present at the enamel-free surfaces of maxillary teeth in the frog Rana pipiens were examined by electron microscopy at different stages of tooth development. Their main fine structural features seem to reflect a transport function. During early tooth development, the non-secretory ameloblasts adjacent to odontoblasts and predentin exhibit extensive lateral surface specializations and numerous cytoplasmic vesicles. During late tooth development, the non-secretory ameloblasts adjacent to mineralizing dentin show numerous cellular junctions, well-developed intercellular channels with numerous interdigitating processes and labyrinthine configurations at their distal surfaces. An intact basal lamina is present between the non-secretory ameloblasts and the dentin surface until the dentin becomes fully mineralized. At this stage the adjacent cells no longer exhibit surface specializations. It is suggested that the non-secretory ameloblasts may participate in the mineralization of adjacent dentin at the enamel-free surfaces. This surface dentin becomes fully mineralized at a later stage of development than the underlying dentin. 相似文献
103.
Siti Sarah Omar Zaki Livashini Kanesan Ming Yeh Danielle Leong Sharmili Vidyadaran 《Cell biology international》2019,43(10):1201-1204
Our work cautions against the use of serum‐supplemented culture media in a transwell migration assay when using chemoattractants other than FBS. At 24 h, a 5% foetal bovine serum (FBS) gradient caused BV2 microglia to migrate toward the lower compartment of the transwell apparatus. Interestingly, FBS‐supplemented media in the absence of a gradient also resulted in notable microglia migration. Serum can therefore confound the interpretation of a transwell migration assay when another chemoattractant is used. 相似文献
104.
Raynner RD Barboza Wedson de MS Souto José da S Mourão 《Journal of ethnobiology and ethnomedicine》2007,3(1):1-14
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105.
106.
107.
Background
Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India 相似文献108.
There has been no culture method of choice for detecting non-O157 Shiga toxin-producing Escherichia coli strains (STEC) because of their biochemical diversity The aim of this study was the assessment of verotoxin gene detection (VT1/VT2) within STEC PCR compared with the Vero cells cytotoxicity among O157 and non-O157 STEC serotypes. Stool cultures were performed on Tryptic Soy Broth and sorbitol MacConkey agar with cefixitime and tellurite supplements which were identified as Escherichia coli (E. coli) by BBL crystal. Further identifications were performed including verotoxin production assessment by Vero cells cytotoxicity assay, PCR for specific VT1/VT2 genotyping, and isolates were plated on blood agar and tested for enterohemolysis. Vero cells cytotoxicity assay revealed that 58 of E. coli isolates (71.6%) were STEC. In PCR, 33 (56.9%) of the 58 strains were positive for the VT2 gene, 24 (41.4%) were positive for the VT1 gene and one isolate was positive for both genes. In comparison to Vero cells cytotoxicity, the sensitivity, specificity of PCR were 100%. In comparative study between verotoxin assessment by Vero cells cytotoxicity and enterohemolytic activity, concordance positive results between both were 53 (91.4%). The most common serogroups of STEC were O157 (33%) and O26 (20%). From this study we can conclude that enterohemolysin production can be used as surrogate marker for STEC. The most rapid and promising approach for detection of STEC is by molecular method. 相似文献
109.
Liu Z Zaki MH Vogel P Gurung P Finlay BB Deng W Lamkanfi M Kanneganti TD 《The Journal of biological chemistry》2012,287(20):16955-16964
Citrobacter rodentium is an enteric bacterial pathogen of the mouse intestinal tract that triggers inflammatory responses resembling those of humans infected with enteropathogenic and enterohemorrhagic Escherichia coli. Inflammasome signaling is emerging as a central regulator of inflammatory and host responses to several pathogens, but the in vivo role of inflammasome signaling in host defense against C. rodentium has not been characterized. Here, we show that mice lacking the inflammasome components Nlrp3, Nlrc4, and caspase-1 were hypersusceptible to C. rodentium-induced gastrointestinal inflammation. This was due to defective interleukin (IL)-1β and IL-18 production given that il-1β(-/-) and il-18(-/-) mice also suffered from increased bacterial burdens and exacerbated histopathology. C. rodentium specifically activated the Nlrp3 inflammasome in in vitro-infected macrophages independently of a functional bacterial type III secretion system. Thus, production of IL-1β and IL-18 downstream of the Nlrp3 and Nlrc4 inflammasomes plays a critical role in host defense against enteric infections caused by C. rodentium. 相似文献
110.
Zaki ME Soliman HA Hiekal OA Rashad AE 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(1-2):1-5
Pyrazolopyranopyrimidines 6a-c and 8a-c were prepared from the reaction of compounds 4a-c or 7a-c with methylamine or ammonium hydroxide solutions. Treatment of compounds 6a-c or 8a-c with 2-chloroethyl methyl ether afforded their corresponding acyclonucleosides 9a-c or 10a-c, respectively, as a new class of acyclonucleosides. All prepared compounds were tested as anti-inflammatory agents and some of them revealed moderate to potent anti-inflammatory activity. 相似文献