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31.
The present study was designed to investigate the relationship between intra-and inter-individual differences in arousal level and performance on both critical flicker fusion frequency and figural reversal tasks. Forty male undergraduate Ss were used. Electrical skin conductance was used as the indicant of arousal level. For the intra-individual comparisons white noise was used to increase the Ss’arousal levels. Significant inverted U-shaped relationships were found between both flicker fusion thresholds and rates of figural reversal and skin conductance between individuals. A significant curvilinear relationship was found between rates of figural reversal and level of conductance within individuals. No significant curvilinear relationship was found between flicker fusion thresholds and level of conductance within individuals.  相似文献   
32.
Summary A formula relating oncotic pressure torat serum protein concentration was derived and found to be in complete agreement with the Landis-Pappenheimer formula derived from measurements onhuman plasma.This study was supported by the Danish Medical Research Council and Johan and Hanne Weimann's legacy.  相似文献   
33.
Summary In this study we attempted to determine the effects of exercise training at the intensity corresponding to lactate threshold (Thla ) on various health-related variables in sedentary but apparently healthy elderly subjects. Six men and five women volunteers [mean age 68.9 (SD 3.4) years] performed supervised endurance-type training on stationary cycle ergometers for 30 min and recreational activities for 30 min, 3 days a week for 12 weeks. Four men and four women served as the control group [68.8 (SD 4.4) years]. As a result of the training programme, statistically significant increases in maximal oxygen consumption (10%), oxygen consumption at Thla (18%), distance covered in 12-min walk, side step, and leg extensor power were found in the training group, while no changes occurred in the control group. The changes in serum cholesterol and triglyceride concentrations from the pre- to post-training period were statistically significant. High-density lipoprotein cholesterol remained unchanged, and low-density lipoprotein cholesterol tended to decrease following the training programme. These data would indicate that exercise training at the intensity corresponding to Thla may have favourable effects on overall physical fitness and some serum lipid variables in older individuals.  相似文献   
34.
The effects of hyperfiltration induced due to unilateral nephrectomy on immunologically induced glomerular injuries were studied. Glomerulonephritis was induced in rats by sensitizing them with egg albumin as an antigen. Unilateral nephrectomy did not affect the removal rate of the antigen from the glomeruli in the rats, but accelerated the rate of the glomerular injuries after cessation of the immunologically induced glomerular inflammation. The histopathological features were characterized by sciero-adhesive lesions with aneurysmal dilatation and hyalinosis of the glomerular capillaries. The parietal epithelial cells extended from the Bowman's capsule with matrices to cover the denuded basement membrane and formed adhesions. The neighboring capillaries collapsed, and the sclero-adhesive lesions progressed. These findings indicate that hyperfiltration at the capillary level did not accelerate the recovery from glomerulonephritis, but induced glomerular sclerosis with adhesions and deteriorated the trivial glomerular injuries to produce similar focal segmental lesions.  相似文献   
35.
The aim of this study was to determine the blood protein changes during different stages of pregnancy and to compare with prepregnancy diestrus in ewes. A total of 90 blood samples were taken from ten Makuii ewes (the native sheep breed in Iran) at diestrus and on days 8, 14, 28, 45, 60, 90, 125, and 145 of pregnancy. Serum protein electrophoresis of samples exhibited four fractions: albumin, α, β, and γ fractions in Makuii ewes, which in α- and γ-globulin bands were divided to α1 and α2; and γ1 and γ2, respectively. The mean concentrations (in gram per deciliter) of total serum proteins, albumin, α1-, α2-, β-, γ1-, and γ2-globulin at diestrus period were 7.03, 3.77, 0.18, 0.74, 0.41, 1.56, and 0.41, respectively. Those values fluctuated nonsignificantly throughout gestation until the 125th day of pregnancy. Thereafter, a significant decrease (p < 0.01) in serum protein levels occurred at the 145th day of pregnancy compared to prepregnancy and other gestational time points. It was concluded that blood protein levels declined sharply during late gestation when the nutrient demands of the fetus were maximal.  相似文献   
36.
17 alpha-Alkylated androgens are highly effective in preventing attacks in HAE patients. These drugs, however, seem to be implicated in the development of cholestatic jaundice, peliosis hepatis, and liver tumors. In order to assess the risk-benefit balance of the long-term therapy with androgen derivatives, a follow-up investigation was performed in 13 HAE patients. The results of this study indicate that long-term treatment (15 to 47 mo) with low doses of danazol or stanozolol does not induce significant hepatic damage detectable by laboratory tests or liver biopsy. However, the limited number of patients, although in a rather long period of observation, still suggests a careful control and the use of minimal effective doses.  相似文献   
37.
Segmentation of Bacteria Image Based on Level Set Method   总被引:1,自引:0,他引:1  
In biology ferment engineering, accurate statistics of the quantity of bacteria is one of the most important subjects. In this paper, the quantity of bacteria which was observed traditionally manuauy can be detected automatically. Image acquisition and processing system is designed to accomplish image preprocessing, image segmentation and statistics of the quantity of bacteria. Segmentation of bacteria images is successfully realized by means of a region-based level set method and then the quantity of bacteria is computed precisely, which plays an important role in optimizing the growth conditions of bacteria.  相似文献   
38.
Summary This study is an attempt to determine the creatine kinase B (CK-B) subunit levels in neurogenic atrophies. A group of 69 patients was studied and the results were compared with those in a group of 32 patients with muscle disease. The results showed that the CK-B levels are considerably higher in patients with amyotrophic lateral sclerosis (P<0.001) and peroneal muscular atrophy (P<0.001). Further studies in the various subgroups of neurogenic atrophies showed that, regardless of the nosological entity, the CK-B activity is considerably higher: (1) in the widespread as opposed to limited forms (P<0.001); (2) in the chronic than in the acute neurogenic atrophies (P<0.001); and (3) in the active as opposed to residual forms (P<0.02). It is suggested that the increase of CK-B in neurogenic atrophies is a strong indication of an active regeneration process in the denervated muscle.  相似文献   
39.
The effects of two kinds of induction speed of sevoflurane anesthesia on the EEG pattern were compared in the same individual using medical student volunteers: a first exposure of 4% was given, followed after full recovery, by incremental doses of 1, 2 and 4% successively, each being administered for 10min. The arterial blood level of the anesthetic was measured using gaschromatograph. The changes of EEG pattern during fast induction with 4% were not represented by the abbreviation of those observed during the slow induction with the incremental doses. The administration of 4% induced a sudden appearance of high voltage, rhythmic slow waves of 2–3Hz at 1–3min when the arterial blood anesthetic level increased maximally, which was then followed by a pattern of faster activities of 10–14Hz mixed with 5–8Hz slow waves. In contrast, the administration of incremental doses induced an increase in frequency and amplitude of EEG activities in the light plane, followed by their decreases in deeper planes. The final EEG patterns were identical for both these methods of induction. These findings confirmed our previous hypothesis that not only the arterial blood level of anesthetics but the rate of its increase are important factors determining the EEG pattern of anesthesia.(Avramov MN et al.: Effects of different speeds of induction with sevoflurane on the EEG in man. J Anesth 1: 1–7, 1987)  相似文献   
40.
Summary To assess the benefit of further gold treatment of rheumatoid arthritis (RA) patients who had already received more than 6 g of this metal, 24 such patients were included in a double-blind trial. Besides this gold group comprising 11 patients who received gold (Auromyose®) in the same dosage schedule as before the study, the trial included a placebo group comprising 13 patients who received gold in a suspension diluted 1/100. In either group clinical, laboratory, and radiological data did not differ after 6 and 24 months in relation to the results at entry except for the serum gold concentrations, which were lower in the placebo group. We conclude that discontinuation of the treatment in RA patients who have received more than 6 g gold is not harmful to the patients for at least two years after withdrawal.  相似文献   
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