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91.
92.
JR Dai LA Decosterd KR Gustafson JH Cardellina GN Gray MR Boyd 《Canadian Metallurgical Quarterly》1994,57(11):1511-1516
During the reisolation of the trimeric naphthoquinone derivative conocurvone [1] from an extract of the Australian shrub Conospermum incurvum, six monomeric naphthoquinones were isolated. These include three novel 1,4-naphthoquinone derivatives: 3-methyl-14,15-dihydro-15-hydroxyteretifolione B [3], 3-methyl-14,15-dihydro-15-hydroxyteretifolione B methyl ether [4], and 2,3-dimethyl-6-hydroxy-7-methoxy-1,4-naphthoquinone [5]. In addition, the previously reported compounds 3-methylteretifolione B [6], 3-methylteretifolione B methyl ether [7], and 8-geranyl-2,7-dihydroxy-3-methyl-1,4-naphthoquinone [8] were isolated and identified. The structures of the novel 1,4-naphthoquinones were elucidated by spectral methods. While conocurvone [1] is a potent inhibitor of HIV-1-induced cell killing, all of the monomeric naphthoquinone derivatives were inactive against HIV-1. 相似文献
93.
LL Bobrov GN Ponomarenko AL Leshchev NB Serebrianaia EB Zhiburt 《Canadian Metallurgical Quarterly》1998,97(3):32-34
A Diabetes Care Management program was developed by PrimeCare, a network model HMO, to improve quality of life health outcomes and reduce the costs of medical care for its members with diabetes. The HMO used a systems-based approach to communicate information about appropriate self-management and standards of care to members and physicians. The focus of the program was to educate and encourage patients to self-manage their illness, and to partner with physicians, other health care providers and community organizations to achieve improved quality of life, clinical and financial results. Clinical process indicators were used to measure results of interventions. Significant increases in the percentage of participants receiving glycosylated hemoglobin (HbA1c) tests, retinal eye exams and lipid panel tests were achieved. 相似文献
94.
VI Lazarenko RI Shatilova GN Goncharova OM Novikov VV Solov'ev GM Sychev IP Artiukhov PG Il'inykh LA Barkhatova VV Ivanov 《Canadian Metallurgical Quarterly》1995,111(3):30-31
The authors present their experience gained in the training of ophthalmologists at the Chair of Ocular Diseases of the Krasnoyarsk Medical Institute. In 1991 the interns, instead of traditional state examinations, maintained their diploma research, which was assessed as their skills and knowledge in the field of ocular diseases, social hygiene, and public health organization. The authors prove that such diploma research is an integral part of undergraduate training and one of the types of individual work at higher educational institutions, and enumerate the topics of diploma research. 相似文献
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96.
SV German GJ Kuper GN Kopylova GE Samonina GV Vorozhe?kina ZV Bakaeva RD Platonova 《Canadian Metallurgical Quarterly》1998,36(4):10-12
The effects of the pancreatic polypeptide amyline on ulceration and acid gastric secretion were studied in rat experiments. Pyloric ligation was used as a model of ulceration. Amyline administration caused significantly less gastric mucosal damage in response to pyloric ligation. The severity of gastric mucosal damage averaged 47 +/- 13 mm2 in the control group and 25 +/- 11 mm2 (p < 0.005). The rate of acid gastric secretion in the animals whose pylorus had been ligated as judged by the pH of gastric content was significantly higher than that in the controls (2.87 +/- 0.22 and 2.34 +/- 0.17 (p = 0.05). It is concluded that amyline has a noticeable effect on the gastric mucosa. It is suggested that suppressed acid gastric secretion, i.e. reduced influence of aggressive agents on the gastric mucosa, is a mechanism of antiulcerative action of the peptide. 相似文献
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Occupational exposure to low levels of nitrous oxide (N2O) have been associated with adverse health effects. The National Institute for Occupational Safety and Health has established a threshold guideline of 25 ppm N2O. The purpose of this laboratory study was to determine the effectiveness of a high-volume dental aspirator as a supplemental device to reduce ambient N2O levels in the operatory. The investigation evaluated four experimental groups that were assigned based on whether or not the aspirator was used and on the rate at which operatory ventilation was established (5 or 10 room air exchanges per hour). Ambient N2O levels were monitored at 30 cm from the nasal hood using an infrared spectrophotometer. The room air exchange rate was measured with a flow hood and then manipulated to the desired ventilation rate. N2O levels were detected with a spectrophotometer and data were recorded with a microprocessor that continuously collected data. The results demonstrated that both utilization of supplemental oral aspiration and increased operatory ventilation significantly reduced ambient N2O levels. It was concluded that a high-volume aspirator, when used in conjunction with the normal scavenging system, can significantly reduce ambient N2O levels to within the guidelines established by the National Institute for Occupational Safety and Health. 相似文献
100.
GN Piquette JL Tilly LE Prichard C Simón ML Polan 《Canadian Metallurgical Quarterly》1994,1(4):297-301
OBJECTIVE: The purpose of this study was to determine whether cells acquired from individual human preovulatory follicles undergo apoptosis (physiologic cell death) and, if so, to correlate the degree of apoptosis with characteristics of the follicles or the oocytes derived from the follicles. METHODS: We devised a sensitive nonradioactive method for detecting apoptotic DNA fragmentation in small numbers of cells derived from rat atretic follicles and follicular aspirates of patients undergoing assisted reproductive technologies. RESULTS: Using this method, apoptotic DNA was detected in rat atretic follicles, with optimal detection at 10-100 ng. Furthermore, apoptotic DNA was detected in some, but not all individual human follicular aspirates from several patients, and was found in follicles that produced oocytes that fertilized and developed into embryos. CONCLUSION: Apoptosis occurs in cells from human ovarian preovulatory follicles and may be a normal physiologic process of the follicle during luteinization. 相似文献