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排序方式: 共有819条查询结果,搜索用时 17 毫秒
101.
102.
AR Patwardhan S Vallurupalli JM Evans EN Bruce CF Knapp 《Canadian Metallurgical Quarterly》1995,79(3):1048-1054
We investigated the effects of voluntary control of breathing on autonomic function in cardiovascular regulation. Variability in heart rate was compared between 5 min of spontaneous and controlled breathing. During controlled breathing, for 5 min, subjects voluntarily reproduced their own spontaneous breathing pattern (both rate and volume on a breath-by-breath basis). With the use of this experimental design, we could unmask the effects of voluntary override of the spontaneous respiratory pattern generator on autonomic function in cardiovascular regulation without the confounding effects of altered respiratory pattern. Results from 10 subjects showed that during voluntary control of breathing, mean values of heart rate and blood pressure increased, whereas fractal and spectral powers in heart rate in the respiratory frequency region decreased. End-tidal PCO2 was similar during spontaneous and controlled breathing. These results indicate that the act of voluntary control of breathing decreases the influence of the vagal component, which is the principal parasympathetic influence in cardiovascular regulation. 相似文献
103.
OBJECTIVE: The aim of this meta-analysis was to review the existent evidence on the effectiveness of tolrestat in the treatment of diabetic peripheral neuropathy. RESEARCH DESIGN AND METHODS: Individual patient data on 738 subjects from the three randomized clinical trials published on this topic were analyzed using changes in motor nerve conduction velocities (NCVs) as endpoints. Nerves investigated included median, ulnar, tibial, and peroneal. RESULTS: The pooled analysis of NCV taken as a continuous measurement showed a significant treatment effect, the magnitude of this benefit being approximately equal to 1 m/s for all the nerves investigated. When looking at the proportion of patients experiencing a loss of NCV of at least 1 or 2 m/s in at least two out of the four nerves investigated, it emerged that treatment reduced by > 40% the risk of such outcomes after adjusting for patients' characteristics. The odds ratios relative to the placebo group were 1.82 (1.30-2.52) and 1.70 (1.15-2.48) for a decrease of 1 and 2 m/s, that is, placebo-treated patients have an 82 and 70% increased risk for a loss of nerve function of 1 and 2 m/s, respectively. No statistically significant difference in treatment effect emerged after stratification according to baseline motor NCV and glycated hemoglobin levels. CONCLUSIONS: After a treatment duration ranging between 24-52 weeks, patients treated with tolrestat had a reduced risk for developing nerve function loss compared with placebo-treated patients. Future long-term trials are needed to evaluate the impact of the treatment on more clinically meaningful endpoints such as the development of foot complications. 相似文献
104.
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KL Gatford TP Fletcher IJ Clarke PC Owens KJ Quinn PE Walton PA Grant BJ Hosking AR Egan EN Ponnampalam 《Canadian Metallurgical Quarterly》1996,74(6):1314-1325
The effects of sex and age on patterns of circulating somatotropin (ST) concentration and plasma IGF-I, IGF-II, insulin, and IGF binding protein-3 (IGFBP-3) were studied in ram, wether, and ewe lambs (n = 7 or 8) sampled at mean ages of 81 (I1) and 158 d (I2). Between 81 and 158 d of age, rams grew more rapidly than wethers (P < .01), and wethers grew more rapidly than ewes (P < .01). The sex differences in growth were reflected in empty body weight at slaughter: rams > wethers > ewes (P < .05). Mean plasma ST concentrations, ST pulse amplitude, and integrated plasma ST concentrations were greater (P < .05) in rams than in ewes at I1 and I2. Characteristics of the ST plasma profile in wethers were generally intermediate between those of rams and ewes. The interpulse interval was greater in ewes than in wethers at I2. The IGF-I and IGFBP-3 concentrations were greater in rams than in ewes at both sampling times. Plasma IGF-II was greater in ewes than in rams at I2. Mean plasma ST was approximately two thirds less at I2 than at I1 regardless of sex. Mean plasma ST and IGF-I at both ages were positively correlated with growth. Mean plasma ST at I2 was negatively correlated with fatness at slaughter. Sex and age significantly affected patterns of circulating ST and concentrations of IGF-I and IGFBP-3 in prepubertal growing lambs, under conditions for which growth rates and composition were also sexually dimorphic. 相似文献
106.
MK Chekhranova ER Shuvalova EN Ilína DIu Pankov SB Diabirova IuA Pankov 《Canadian Metallurgical Quarterly》1994,(12):17-19
A human insulinoma cDNA library was constructed in the expression plasmid vector pUEX1. The clone pUEX1Ins12 was selected by means of hybridization with an insulin probe. It codes for full size amino acid sequence preproinsulin. The bacterial strain pUEX3Ins8 producing proinsulin as beta-galactosidase fusion protein was obtained for the use of recombinant protein as an antigen in an ELISA to detect serum antibodies in subjects with IDDM. Recombinant clones containing the middle, N- and C-terminal domains of the GAD65, the major autoantigen in IDDM, were constructed in pVEX1. These clones may become important tools to study the nature of GAD autoreactivity in IDDM. The clone pHICEO.9 was selected from the human insulinoma cDNA library by immunoscreening with total human insulinoma protein antibodies. This clone expresses the C-terminal fragment of human cholesterol esterase/lipase containing its antigenic determinant and can be used for blood lipase determination. Four clones containing cDNA inserts (0.47-1.42 kb) without any significant homologies to the known sequences in the Gene Bank were obtained by means of statistic selection. 相似文献
107.
The purpose of this study was to estimate the risk of suicide for patients with Parkinson's disease (PD) in Denmark compared with that in the background population. The study involved 458 patients with a PD diagnosis, 226 men and 232 women. The follow-up period to either death or end of follow-up on December 31, 1990 was 0 to 17 years, mean 5.7 years. Deaths in the follow-up period amounted to 254, 135 men and 119 women. Two women committed suicide. The number of expected suicides was 1.06 for men and 0.55 for women, a total of 1.62. Neither for men nor for women was the difference between expected and observed suicides statistically significant. 相似文献
108.
109.
An inhibition ELISA (IH-ELISA) test for foot-and-mouth disease virus (FMDV) was validated using 106 epithelial samples from suspected cases of FMD in Argentina submitted to the Argentine National Diagnostics Laboratory (GELAB) over a period of 12 months and examined in parallel with the complement fixation test (CFT). IH-ELISA was found to be more sensitive, detecting 25% (26 samples) more FMDV positives than the CFT in original suspensions of field samples. The effect of storage conditions on 12S stability was examined. Plates stored at 4 degrees C blocked with 1% ovalbumin and plates stored at -20 degrees C with or without blocking buffer could be used for at least 90 days. When various brands of polystyrene plates were compared for 12ps adsorption it was found that those microplates of higher binding capacity were more efficient. 相似文献
110.