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71.
MB Fisso 《Canadian Metallurgical Quarterly》1998,34(2):265-274
A study of a variety of stationary phases and elution conditions for the liquid chromatographic (LC) determination of six biologically active green tea catechins has resulted in the development of two well-defined, reproducible systems for such analyses which overcome limitations of previously described methods. Comparison of six reversed-phase columns indicates that deactivated stationary phases, which utilize ultrapure silica and maximize coverage of the silica support, provide significantly improved separation and chromatographic efficiencies for catechin analyses using LC, compared to conventional monomeric or polymeric C18 columns. Evaluation of elution conditions used for the separations reveals that the presence of acid in the mobile phase (0.05% trifluoroacetic acid) is essential for both the complete resolution of the catechins present in tea and the efficient chromatography of these compounds. The efficacy of one of the developed systems was demonstrated by the quantitative measurement of the six biologically active catechins in aqueous infusions of green tea (Camellia sinensis). Overall precision values for the analyses were within the range 0.3-1% (relative standard deviation). 相似文献
72.
CT Furstenberg TA Ahles MB Whedon KL Pierce M Dolan L Roberts PM Silberfarb 《Canadian Metallurgical Quarterly》1998,15(6):335-349
The knowledge and attitudes toward cancer pain management of physicians, nurses, and pharmacists in the state of New Hampshire were examined through the use of a statewide survey. Many of the providers who completed the survey, and thus indicated that they treated patients with cancer pain on a regular basis, were not pain or oncology specialists. Most of these providers were quite well informed about the fundamentals of cancer pain management. Approximately 90% of providers in all three groups were not concerned about addiction among cancer patients. Yet, there was a small percentage of providers who responded in less than optimal ways to items dealing with opioid pharmacology, pain assessment, and the importance of pain relief. Comparison of responses among provider groups indicated that nurses were the most knowledgeable and pharmacists the least knowledgeable about pain assessment. Physicians were the most knowledgeable regarding opioid pharmacology but seemed the least committed to providing optimal pain relief. Further analysis identified a small group of physicians that included a disproportionately high percentage of family practitioners and surgeons who consistently responded in less than optimal ways to items dealing with the importance of pain relief. The results of this study indicate a continuing need for broad-based educational programs in cancer pain management and for new initiatives focused on practitioners who see relatively few cancer patients and may have difficulty accessing traditional educational programs. 相似文献
73.
K Garde AC Mortensen PB Toft MB S?rensen FF Madsen O Henriksen 《Canadian Metallurgical Quarterly》1994,35(2):197-200
The yeast gene, YTA10, encodes a member of a novel family of putative ATPases. Yta10p, as deduced from the nucleotide sequence, is 761 amino acids in length (predicted molecular mass 84.5 kDa). The amino acid sequence of Yta10p exhibits high similarity to two other yeast proteins, Yta11 and Yta12, and to E. coli FtsH. Several features of Yta10p are compatible with its localization in mitochondria. We report here that Yta10p is a yeast mitochondrial protein and that import is dependent on a membrane potential and accompanied by processing to a protein of approximately 73 kDa. Disruption of YTA10 leads to a nuclear petite phenotype and to a loss of respiratory competence, as shown by spectrophotometric measurement of the activities of respiratory complexes I-III and IV, respectively. These findings together with the high similarity of Yta10p to several ATP-dependent proteases suggest that Yta10p is a mitochondrial component involved, directly or indirectly, in the correct assembly and/or maintenance of active respiratory complexes. 相似文献
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75.
MB Melo FF Costa ST Saad I Lorand-Metze S Bordin NN Ahmad 《Canadian Metallurgical Quarterly》1998,22(9):787-792
Patient 1: A 48-year-old man was admitted to Osaka Red Cross Hospital because of fever and dyspnea. Laboratory examination revealed pancytopenia, liver dysfunction and hematostatic abnormality. Chest radiographs obtained on admission revealed ground-glass opacity in both lung fields, and an analysis of arterial blood showed severe hypoxemia (PaO2:46.8 Torr). Pulse therapy with methylprednisolone was started. Although the hypoxemia subsided and radiographic findings rapidly improved, pancytopenia persisted. Examination of bone marrow aspirate revealed mature histiocytes with marked hemophagocytosis. Amplified Mycobacterium tuberculosis direct tests of bronchoalveolar lavage fluid, sputum, urine, and bone marrow were all positive, and Mycobacterium tuberculosis was cultured from sputum and urine. Although the patient was taking antituberculous agents, his pancytopenia persosted. Treatment with etoposide induced remssion. Patient 2: A 19-year-old woman was admitted to Osaka Red Cross Hospital because of prolonged cough and fever. Laboratory examination revealed leukocytosis, liver dysfunction, and hematostatic abnormality. Serologic tests provided conclusive evidence of Mycoplasma infection and a CRP test was strongly positive. Chest radiographs obtained on admission revealed infiltration shadows in the middle and lower lung fields on both sides, with left pleural effusion. An analysis of arterial blood showed hypoxemia (PaO2: 54.2 Torr). Examination of bone marrow and pleural effusion samples revealed mature histiocytes with marked hemophagocytosis. Although treatment with antibiotics and pulse therapy with methylprednisolone was started, the patients respiratory functions deteriorated. Endotracheal intubation was performed. Therapy with etoposide induced remission. Hemophagocytic syndrome associated with Mycoplasma infection and tuberculosis appears to be exceedingly rare. In these 2 cases, it was difficult to achieve remission with therapy for the underlying infections, but etoposide treatment was effective. 相似文献
76.
The mechanisms underlying secondary or delayed cell death following traumatic brain injury (TBI) are poorly understood. Recent evidence from experimental models of TBI suggest that diffuse and widespread neuronal damage and loss is progressive and prolonged for months to years after the initial insult in selectively vulnerable regions of the cortex, hippocampus, thalamus, striatum, and subcortical nuclei. The development of new neuropathological and molecular techniques has generated new insights into the cellular and molecular sequelae of brain trauma. This paper will review the literature suggesting that alterations in intracellular calcium with resulting changes in gene expression, activation of reactive oxygen species (ROS), activation of intracellular proteases (calpains), expression of neurotrophic factors, and activation of cell death genes (apoptosis) may play a role in mediating delayed cell death after trauma. Recent data suggesting that TBI should be considered as both an inflammatory and/or a neurodegenerative disease is also presented. Further research concerning the complex molecular and neuropathological cascades following brain trauma should be conducted, as novel therapeutic strategies continue to be developed. 相似文献
77.
CG B?nnemann J Wong C Ben Hamida MB Hamida F Hentati LM Kunkel 《Canadian Metallurgical Quarterly》1998,8(3-4):193-197
Four of the currently recognized autosomal recessive limb-girdle muscular dystrophies (LGMD type 2C-F) are caused by mutations in the genes encoding components of the sarcoglycan complex. LGMD 2C, caused by mutations in gamma-sarcoglycan, is prevalent in northern Africa, especially in Tunisia, where this type of muscular dystrophy was originally described. Although the disease initially was assumed to be genetically homogeneous in this region, linkage to the alpha-sarcoglycan locus (LGMD 2D) has also been found. We have now identified the first Tunisian family with beta-sarcoglycanopathy (LGMD 2E), further adding to the genetic heterogeneity of autosomal recessive LGMD in this population. Direct sequencing of the beta-sarcoglycan gene revealed a homozygous mutation (G272-->T, Arg91Leu) in exon 3. This change affects the same arginine residue in the immediate extracellular domain of the protein that was mutated to a proline (G272-->C, Arg91Pro) in a Brazilian family with a severe form of the disease. Immunohistochemical analysis for the sarcoglycan complex demonstrates absence of the known components of the complex in both of these families. We postulate that the immediate extracellular domain of beta-sarcoglycan may be important for the assembly and/or maintenance of this complex, potentially mediated by disulfide-bond formation to another sarcoglycan via the single cysteine residue in that domain. 相似文献
78.
79.
BACKGROUND AND OBJECTIVES: To evaluate the benefit of measuring the intraocular pressure (IOP) on the first postoperative day after argon laser trabeculoplasty (ALT). PATIENTS AND METHODS: We retrospectively reviewed 407 ALT procedures with perioperative apraclonidine performed on 226 patients between January 1991 and December 1993. Data analyzed included type of glaucoma, extent of treatment, whether the procedure was initial or repeat, laser parameters, and IOP preoperatively and at 1 hour, 1 day, and 1 month postoperatively. RESULTS: The percentage of patients with an IOP rise of greater than 3 mm Hg at 1 hour, 1 day, and 1 month following ALT was 11.3%, 4.2%, and 5.2% respectively. The incidence of IOP elevations greater than 10 mm Hg was 2.2%, 1.0%, and 1.5% at 1 hour, 1 day and 1 month, respectively. Of 17 cases with an IOP elevation greater than 3 mm Hg at 1 day, four eventually required a trabeculectomy. However, there were no consistent factors that distinguished which cases with elevated IOP at 1 day ultimately needed further therapy, nor did the 1-day postoperative examination predict which patients would have IOP elevation at 1 month. CONCLUSION: IOP 1 day after ALT is rarely elevated and does not correlate with IOP elevation at 1 month. Therefore, an IOP check at 1 day is not felt to be necessary for most patients. 相似文献
80.