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991.
Hugh Hudson 《History of Photography》2019,43(3):266-283
In the second half of the nineteenth century, the Montefiores were an international Jewish family including prominent bankers, insurers, and merchants. Four brothers of the family were also leading members of the amateur photography movement in Britain, Belgium, France, and Australia. An album containing photography now in the State Library of New South Wales in Sydney, but made by Eliezer Levi Montefiore in the Colony of Victoria, reveals aspects of his family’s identity. The album reflects their role in the British colonisation of Australia, as well as their interest in the development of Australian national identity. The enthusiasm for photography manifest in the album was shared by the brothers across national borders, and so also reflects their transnational, diasporic experience. Furthermore, the album represents aspects of the family’s class and gender identities, and functioned as a kind of visual primer for its recipient, Eliezer’s young daughter, Caroline. 相似文献
992.
N Guerreiro T Stepkowski BG Rolfe MA Djordjevic 《Canadian Metallurgical Quarterly》1998,19(11):1972-1979
We have used proteome analysis of derivatives of R. leguminosarum biovar trifolii strain ANU843, cured of indigenous plasmids by a direct selection system, to investigate plasmid-encoded functions. Under the conditions used, the plasmid-encoded gene products contributed to only a small proportion of the 2000 proteins visualised in the two-dimensional (2-D) protein map of strain ANU843. The level of synthesis of thirty-nine proteins was affected after curing of either plasmid a, c or e. The differences observed upon plasmid curing included: protein loss, up/down-regulation of specific proteins and novel synthesis of some proteins. This suggests that a complex interplay between the cured plasmid and the remaining replicons is occurring. Twenty-two proteins appeared to be absent in the cured strains and these presumably are encoded by plasmid genes. Of these, a small heat shock protein, a cold shock protein, a hypothetical YTFG-29.7 kDa protein, and the alpha and beta subunits of the electron transfer flavoprotein were identified by N-terminal microsequencing and predicted to be encoded by plasmid e. Four of the sequenced proteins putatively encoded on plasmid e and two encoded on plasmid c were novel. In addition, curing of plasmid e and c consistently decreased the levels of 3-isopropylmalate dehydratase and malate dehydrogenase, respectively, suggesting that levels of these proteins may be influenced by plasmid-encoded functions. A protein with homology to 4-oxalocrotonate tautomerase, which is involved in the biodegradation of phenolic compounds, was found to be newly synthesised in the strain cured of plasmid e. Proteome analysis provides a sensitive tool to examine the functional organisation of the Rhizobium genome and the global gene interactions which occur between the different replicons. 相似文献
993.
994.
HF Vasen M van Ballegooijen E Buskens JK Kleibeuker BG Taal G Griffioen FM Nagengast FH Menko P Meera Khan 《Canadian Metallurgical Quarterly》1998,82(9):1632-1637
BACKGROUND: It has been estimated that the prevalence of carriers of a mutated mismatch repair (MMR) gene among the general population in Western countries is between 5 and 50 per 10,000. These carriers have a risk of >85% of developing colorectal carcinoma (CRC) and therefore need careful follow-up. The objective of this study was to analyze the cost-effectiveness of CRC surveillance of carriers of a mutated MMR gene. METHODS: The authors constructed a model to estimate the potential health effects (life expectancy) and healthcare costs of two strategies: 1) surveillance, with colonoscopy every 2-3 years, and 2) no CRC surveillance. Estimates of the lifetime risk of developing CRC and the stage distribution of CRC for symptomatic patients were derived from the Dutch hereditary nonpolyposis colorectal carcinoma (HNPCC) registry. The CRC stage specific relative survival rates and the effectiveness of surveillance in preventing or detecting cancer early were based on Finnish studies. The costs of surveillance and treatment were derived from recent American studies. RESULTS: The results showed that 1) surveillance of gene carriers led to an increase in life expectancy of 7 years, and 2) the costs of surveillance under a wide range of assumptions are less than the costs of no CRC surveillance. CONCLUSIONS: CRC surveillance of HNPCC gene carriers appears to be effective and considerably less costly than no CRC surveillance and therefore deserves to be supported by governmental agencies and health insurance organizations. 相似文献
995.
Methods that increase processing efficiency to save energy costs and to improve yield and volume must be evaluated in terms of maintaining or improving final product quality. Shear tests measure the force to cut through fibers of cooked samples. They are the simplest and most common tests used to document cooked meat texture. However, information obtained from shearing devices that perform in a similar way may not be interchangeable. In this study, three shearing devices were assessed. Eight treatments were imposed on broiler breasts processed under commercial conditions to represent ranges of texture characteristics. Treatments included electrical stimulation (S), or no stimulation (NS) of carcasses; postchill deboning at 2 or 6 h; and marination (M), or no marination (NM). Shear force values of cooked breasts were obtained from the benchtop Warner-Bratzler (BT-WB) machine, the Warner-Bratzler blade attachment (TA-WB) and a 45 degrees chisel-end blade attachment (TA-WD). The TA-WB and TA-WD were attached to Model TA.XT2 texture analyzer. For each device, shear value differences were significant (P < 0.05) for deboning time. Marination effects were significant (P < 0.05) for BT-WB and TA-WB. Stimulation by debone interactions were significant (P < 0.05) for BT-WB and TA-WD. The TA-WD values varied the greatest over all treatments (SD = 5.52; SE = 0.65). Variations of BT-WB and TA-WB shear values were similar (SD = 3.25, 2.97, respectively; SE = 0.38, 0.35). 相似文献
996.
BG Lindsay DR Sieglaff DA Schafer CL Hakes KA Smith RF Stebbings 《Canadian Metallurgical Quarterly》1996,53(1):212-218
We investigated the electrocortical (E.Co.G) correlates of visceral (topical capsaicin application or overdistension of the urinary bladder) and somatic (perineal pinching) painful stimulation in urethane-anesthetized rats and their modulation by intrathecal application of selective tachykinins receptors (NK 1 and NK 2) antagonists. Vesical overdistension or topical capsaicin on the bladder serosal surface produced an immediate and lasting E.Co.G. desynchronization resembling a cortical arousal. A second application of capsaicin was ineffective. Bladder contraction induced by topical acetylcholine did not alter E.Co.G. A desynchronized E.Co.G. was also induced by pinching of the perineal area of the rat. Intrathecal administration of lidocaine at lumbosacral level abolished the E.Co.G. desynchronization induced by both visceral and somatic noxious stimulation. On the other hand capsaicin-induced or over-distension (but not pinching-induced) E.Co.G. desynchronization disappeared in animals systemically pretreated with capsaicin or after intrathecal administration of NK 1 tachykinin receptor antagonists such as the peptide GR 82334 or the nonpeptide RP 67580, whereas the inactive enantiomer RP 68651 or the nonpeptide NK 2 antagonists SR 48968 were ineffective. In conclusion, the experimental model described herein, allowing a quantitative analysis of the E.Co.G. correlates of visceral and somatic noxious stimulation in urethane-anesthetized rats, provides evidence for a specific neural pathway carrying bladder-arising visceral (both mechanical and chemical) nociception that uses pelvic capsaicin-sensitive afferents projecting to NK 1 (but not NK 2) bearing spinal neurons and that ultimately leads to activation of cortical areas. 相似文献
997.
The subcellular distribution of folate coenzymes in the brain is unknown. Brain folate concentrations are low and hence require a sensitive assay to determine the subcellular distribution. Rat brain was fractionated by differential centrifugation into cytoplasmic, mitochondrial and crude synaptosomal fractions. The compositions of the folate pools in these subcellular fractions were determined by differential conversion of one-carbon forms enzymatically to 5,10-methylenetetrahydrofolate (5,10CH2H4PteGlu(n)) followed by reaction of the 5,10CH2H4PteGlu(n) with thymidylate synthetase and [3H]fluorodeoxyuridylate to form ternary complexes, which were then separated as a function of polyglutamate chain length by isoelectric focusing, visualized by fluorography and quantified by densitometry. The distribution of the pteridine derivatives in brain was very similar to the distribution of these derivatives in liver. Cytoplasm contained primarily 5-methyltetrahydropteroylpolyglutamates with smaller amounts of unsubstituted tetrahydropteroylpolyglutamates, whereas mitochondria contained approximately equal concentrations of unsubstituted and formyl-substituted tetrahydropteroylpolyglutamates. The subcellular distribution of polyglutamate derivatives in brain, however, was different from that in liver. In the brain, the mitochondrial folates exhibited longer polyglutamate chains than did the cytoplasmic folates, a pattern opposite to that in the liver. Whereas the brain cytoplasmic pteroylpolyglutamates were primarily penta and hexa glutamates, the brain mitochondrial pteroylpolyglutamates were primarily hexa and hepta glutamates. The brain also contained small but measurable levels of oxidized folates, which were seen in crude synaptosomal fractions but not in cytoplasmic or mitochondrial fractions. 相似文献
998.
999.
T Hudson 《Canadian Metallurgical Quarterly》1997,71(24):26-27
Hospitals and physician practices may for pricey partners: The median hospital-owned operation looses a sizable $57,000 a year. That number and others--compiled exclusively for H&HN by the Medical Group Management Association--beg big questions about how long hospitals can continue to subsidize unprofitable practices. 相似文献
1000.
BG Green 《Canadian Metallurgical Quarterly》1996,68(2-3):245-253
Topical desensitization of the tongue was assessed during multiple bouts of exposure to capsaicin. In the first experiment subjects rated perceived irritation as 30 capsaicin stimuli (33 microM) were applied to the tongue tip in three blocks of 10, with 15 min breaks between blocks. Significant desensitization was measured at the beginning of the second and third blocks within each session. However, as stimulation continued within those blocks sensations of irritation grew toward undesensitized levels ('stimulus-induced recovery' (SIR)). Desensitization did not extend across days. The second experiment employed a 10-fold higher concentration of capsaicin (330 microM) to determine if SIR was limited to low levels of desensitization. SIR occurred as before within sessions, and the higher concentration produced desensitization across days that also exhibited recovery during the first block of stimuli on days 2 and 3. The third experiment included piperine, zingerone and citric acid as stimuli to determine if SIR was specific to capsaicin. Piperine produced SIR under conditions of both self- and cross-desensitization with capsaicin, whereas recovery failed to materialize with zingerone. Citric acid was not significantly cross-desensitized by capsaicin, so recovery could not be measured. Overall the results demonstrate that desensitization of the tongue produced by either capsaicin or piperine can be temporarily reversed if stimulation with either chemical is resumed for only a few minutes. The implications these findings may have for hypotheses about the mechanisms of capsaicin desensitization and sensitization as well as for clinical applications of capsaicin as a topical analgesic are discussed. 相似文献