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991.
LR McBride R Ruggiero KA Powers DA Moroney MT Swartz 《Canadian Metallurgical Quarterly》1998,65(3):839-841
Clinical and pathologic findings are presented of the first reported case in the English-language medical literature of pseudomesotheliomatous adenocarcinoma (PMA) occurring in an HIV-infected patient. PMA is an uncommon variant of peripheral lung cancer which typically occurs in elderly male patients. It mimics a malignant mesothelioma in terms of its clinical presentation and gross and microscopic appearance. The occurrence of this rare tumor in a young HIV-infected patient suggests some association between HIV infection and the development of PMA. 相似文献
992.
G Hummer S Garde AE García ME Paulaitis LR Pratt 《Canadian Metallurgical Quarterly》1998,95(4):1552-1555
Proteins can be denatured by pressures of a few hundred MPa. This finding apparently contradicts the most widely used model of protein stability, where the formation of a hydrophobic core drives protein folding. The pressure denaturation puzzle is resolved by focusing on the pressure-dependent transfer of water into the protein interior, in contrast to the transfer of nonpolar residues into water, the approach commonly taken in models of protein unfolding. Pressure denaturation of proteins can then be explained by the pressure destabilization of hydrophobic aggregates by using an information theory model of hydrophobic interactions. Pressure-denatured proteins, unlike heat-denatured proteins, retain a compact structure with water molecules penetrating their core. Activation volumes for hydrophobic contributions to protein folding and unfolding kinetics are positive. Clathrate hydrates are predicted to form by virtually the same mechanism that drives pressure denaturation of proteins. 相似文献
993.
SE Kong LR Blennerhassett KA Heel RD McCauley JC Hall 《Canadian Metallurgical Quarterly》1998,68(8):554-561
OBJECTIVES: To compare two programmes for reducing the levels of risk indicators of heart diseases among professional drivers. The programmes were focused on changes of lifestyle. The aim of the programmes was to initiate and motivate a process of change within the driver, which in the long term should lead to permanent and sound health habits. One programme was based on health profile assessment and the other was a health examination. METHODS: Altogether, 102 subjects were investigated (51 allocated to an intervention group and 51 to a reference group). The programme in the intervention group (health profile assessment) was based on revelatory communication, adjusted to the driver and contained individual and group activities. The reference group went through a health examination. In both groups blood pressure, serum lipid concentrations, body mass index, and estimated maximal oxygen uptake were measured and the lifestyle habits were surveyed by questionnaires at the start and at follow ups of 6 and 18 months. RESULTS: The results showed that in the intervention group the maximal oxygen uptake increased, as did exercise habits and the intention to practice good dietary habits. Variable working hours was the most common obstacle to change a health habit. In the reference group the maximal oxygen uptake increased and the concentration of serum total cholesterol and the number of people who perceived stress and loneliness decreased. CONCLUSIONS: Both the health profile assessment and the health examination had an effect on the levels of some risk indicators of heart diseases. Both programmes turned out to be useful because of high participation during the entire period and a generally positive attitude among the subjects. 相似文献
994.
995.
This study was conducted to evaluate morphologic differences in pig oocytes matured in vivo and in vitro, with particular reference to the potential relationship between oocyte morphology and the occurrence of polyspermy after in vitro fertilization (IVF). In vivo-matured oocytes were surgically recovered from the oviducts of gilts with ovulated follicles on day 2 of estrus, and in vitro-matured oocytes were obtained by culturing follicular oocytes in a oocyte maturation system that has resulted previously in production of live offspring following IVF. Comparisons were made of the cytoplasm density, the diameter of oocytes with or without zona pellucida (ZP), the thickness of the ZP, the size of the perivitelline space (PVS), ZP dissolution time, and cortical granule (CG) distribution before IVF, and CG exocytosis and polyspermic penetration after IVF. Oviductal oocytes have clear areas in the cytoplasm cortex, while in vitro-matured oocytes have very dense cortex. The diameter of ovulated oocytes with ZPs was significantly (P < 0.001) greater than that of in vitro-matured oocytes. However, no difference was observed in the diameter of the oocyte proper. Significantly (P < 0.001) thicker ZPs and wider PVSs were observed in the ovulated oocytes. The ZPs of ovulated oocytes were not dissolved by exposure to 0.1% pronase within 2 hr, but the ZPs of in vitro-matured oocytes were dissolved within 131.7 +/- 7.6 sec. The ZPs of ovulated oocytes, but not of in vitro-matured oocytes, were strongly labeled by a lectin from archis hypogaea that is specific for beta-D-Gal(1-3)-D-GalNAc. Polyspermy rate was significantly (P < 0.01) higher for in vitro-matured oocytes (65%) than for ovulated oocytes (28%). CGs of oviductal oocytes appeared more aggregated than those of in vitro-matured oocytes. Most of CGs were released from both groups of oocytes 6 hr after IVF regardless of whether they were polyspermic or monospermic oocytes. These results indicate that in vitro-matured and in vivo-matured pig oocytes possess equal ability to release CGs on sperm penetration. Unknown changes in the extracellular matrix and/or cytoplasm of the oocytes while in the oviduct may play an important role(s) in the establishment of a functional black to polyspermy in pig oocytes. 相似文献
996.
Inadvertent carotid artery puncture is a well-known complication of internal jugular vein cannulation. A case of cerebral infarct subsequent to carotid artery puncture during internal jugular vein cannulation is reported. 相似文献
997.
Truncated multivariate survival models are proposed for the analysis of data from the South Australian Methadone Program. Injecting drug users may have several entries to and exists from the program. A marginal approach for recurrent events is found to provide a useful and simplified basis for modeling the retention of injecting drug users on methadone. The likelihoods and results of fitting two forms of truncated survival models are presented, together with recommendations for statistical analysis using S-PLUS. The relative merits of the marginal approach in this context and alternative ways of viewing the data are discussed. 相似文献
998.
Spectroscopic properties of the redox-active iron in the active site of plant and mammalian lipoxygenases can now be combined with recent crystal structure determinations to obtain new insights into lipoxygenase reaction mechanisms. 相似文献
999.
AM Chapa JM Fernandez TW White LD Bunting LR Gentry TL Ward SA Blum 《Canadian Metallurgical Quarterly》1998,76(11):2930-2937
Two experiments were conducted to investigate the effect of i.v. administration of L-carnitine on selected metabolites in sheep and to determine the feasibility of using L-carnitine to ameliorate the deleterious effects of hyperammonemia in sheep. In Exp. 1, i.v. L-carnitine solutions were administered at three levels in a replicated Latin square: 0 (CONT), 6.36 (CAR 1), and 12.72 (CAR 2) mmol L-carnitine/kg x (75) BW using Suffolk ewes (n = 6; average BW 75+/-3 kg). Plasma L-carnitine concentration was increased (P<.05) by treatment (51.9 vs 102.3, and 96.4 micromol/L in CONT, CAR 1, and CAR 2, respectively). Plasma glucose concentration was elevated (P<.05) in CAR 2 and CAR 1. Plasma NEFA concentration was highest (P<.05) in CAR 2. Area under the response curve for glucose was greater (P<.02) in CAR 2. In Exp. 2, Suffolk ewes (n = 16; average BW 48+/-2 kg) were used in a randomized complete block design with a 2x2 factorial treatment arrangement to determine the effects of i.v. L-carnitine administration during an oral urea load test (OULT). L-Carnitine (0 and 6.36 mmol/kg x (75) BW) was administered i.v. at 30 min, and an oral urea drench (50% wt/vol; 0 and 300 mg/kg BW) was administered at 60 min. Plasma L-carnitine was increased (P<.0001) by i.v. L-carnitine. Plasma ammonia N was highest (P<.0001) in the UREA treatment compared with the CONT, CARN, and CARN + UREA treatments (148 vs 95, 101, and 108 micromol/L, respectively). Intravenous L-carnitine administration influenced plasma glucose and NEFA concentrations in sheep and, when administered 30 min preceding an OULT, prevented the development of subclinical hyperammonemia in sheep. 相似文献
1000.
This study examines differences by age cohort in (a) the frequency of prayer, (b) racial and gender variation in prayer, and (c) religious and sociodemographic correlates of prayer. Analyses are conducted across four age cohorts (18-30, 31-40, 41-60, > or = 61) using data from the 1988 National Opinion Research Center (NORC) General Social Survey (N = 1,481). Findings reveal that prayer is frequently practiced at all ages, but more frequently in successively older cohorts. In addition, females and, to a lesser extent, African Americans pray more frequently than males and Whites, respectively. Further, hierarchical multiple regression analyses reveal statistically significant associations across age cohorts between prayer and key measures of religious behavior, feeling, belief, and experience. 相似文献