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1.
I. K. M. Brenner J. Zamecnik P. N. Shek R. J. Shephard 《European journal of applied physiology and occupational physiology》1997,76(5):445-454
To determine if heat exposure alters the hormonal responses to moderate, repeated exercise, 11 healthy male subjects [age = 27.1
(3.0) years; maximal oxygen consumption, V˙O2max = 47.6 (6.2) ml · kg · min−1; mean (SD)] were assigned to four different experimental conditions according to a randomized-block design. While in a thermoneutral
(23°C) or heated (40°C, 30% relative humidity) climatic chamber, subjects performed either cycle ergometer exercise (two 30-min
bouts at ≈50% V˙O2max, separated by a 45-min recovery interval, CEx and HEx conditions), or remained seated for 3 h (CS and HS conditions). Blood
samples were analyzed for various exercise stress hormones [epinephrine (E), norepinephrine (NE), dopamine, cortisol and human
growth hormone (hGH)]. Passive heating did not alter the concentrations of any of these hormones significantly. During both
environmental conditions, exercise induced significant (P < 0.001) elevations in plasma E, NE and hGH levels. At 23°C during bout 1: E = 393 (199) pmol · l−1 (CEx) vs 174 (85) pmol · l−1 (CS), NE = 4593 (2640) pmol · l−1 (CEx) vs 1548 (505) pmol · l−1 (CS), and hGH = 274 (340) pmol · l−1 (CEx)vs 64 (112) pmol · l−1 (CS). At 40°C, bout 1: E = 596 (346) pmol · l−1 (HEx) vs 323 (181) pmol · l−1 (HS), NE = 7789 (5129) pmol · l−1 (HEx) vs 1527 (605) pmol · l−1 (HS), and hGH = 453 (494) pmol · l−1 (HEx) vs 172 (355) pmol · l−1 (HS). However, concentrations of plasma cortisol were increased only in response to exercise in the heat [HEx = 364 (168)
nmol · l−1 vs HS = 295 (114) nmol · l−1). Compared to exercise at room temperature, plasma levels of E, NE and cortisol were all higher during exercise in the heat
(P < 0.001 in all cases). The repetition of exercise did not significantly alter the pattern of change in cortisol or hGH levels
in either environmental condition. However, repetition of exercise in the heat increased circulatory and psychological stress,
with significantly (P < 0.001) higher plasma concentrations of E and NE. These results indicate a differential response of the various stress hormones
to heat exposure and repeated moderate exercise.
Accepted: 16 April 1997 相似文献
2.
Through the use of principal components analysis of the correlation matrix between excentricity quotients of intra- and inter-individual
transitions between pairs of the 22 most frequent behaviour elements of male and female gelada baboons observed in captivity,
the total variance could be described in terms of a low number of causal factors. In intra-individual sequences the five factors
requested of the analysis explain 74 per cent of the total variance. The following intra-individual groupings were found:
(I) “autostimulation”, (II) “intensive social” versus “groom”, (III) “male sexual”, (IV) “attack” versus “sexual presentation”,
and (V) “greeting” versus “threat”. In inter-individual transitions, the five factors explain 68 per cent of the variance.
The following communicative sets were found: (1) “female-sexual releasing”, (2) “greeting and approaching releasing” versus
“groom releasing”, (3) “austostimulation releasing” versus “male-sexual releasing”, (4) “fight releasing”, and (5) “conflict”.
Mimetic induction of same acts or acts within one particular intra-individual set was frequent. 相似文献
3.
The present study was carried out to assess the impact of wastewater on parsley (Petroselinum crispum). The parameters determined for soil were pH, electrical conductivity (EC), soil organic matter (SOM), nutrient elements
(Ca, Mg, Na, K, Mn, Cu, Zn, and Fe), and heavy metals (Cd, Cr, Ni, and Pb), while the parameters determined for the plant
included pigment content, dry matter, nutrient element, and heavy metals. SOM, EC, and clay contents were higher, and pH was
slightly acidic in soil treated with wastewater compared to control soil. The enrichment factors (EF) of the nutrient elements
in contaminated soil are in the sequence of Na (2) > Ca (1.32) > Mn = Mg (1.17) > Cu (1.11) > Zn (1.08) > Fe (1.07) > K (0.93),
while EF in parsley are Na (6.63) > Ca (1.60) > Mg (1.34) > Zn (1.15) > Fe (0.95) > Cu = K (0.90) > Mn (0.85). Application
of wastewater significantly decreased dry matter, while photosynthetic pigment content increased in parsley. The enrichment
of the heavy metals is in the sequence: Cd (1.142) > Pb (1.131) > Ni (1.112) > Cr (1.095). P. crispum shows a high transfer factor (TF > 1) for Cd signifying a high mobility of Cd from soil to plant. Thus, although the wastewater
irrigation in parsley production aims to produce socioeconomic benefits, study results indicated that municipal wastewater
is not suitable for irrigation of parsley because it has negative effects on plant and causes heavy metal accumulation. 相似文献
4.
This study examined the thermoregulatory responses of men (group M) and women (group F) to uncompensable heat stress. In
total, 13 M [mean (SD) age 31.8 (4.7) years, mass 82.7 (12.5) kg, height␣1.79␣(0.06) m, surface area to mass ratio 2.46␣(0.18) m2 · kg−1 · 10−2, Dubois surface area 2.01 (0.16) m2, %body fatness 14.6 (3.9)%, V˙O2peak 49.0 (4.8) ml · kg−1 · min−1] and 17 F [23.2 (4.2) years, 62.4 (7.7) kg, 1.65 (0.07) m, 2.71 (0.14) m2 · kg−1 · 10−2, 1.68 (0.13) m2, 20.2 (4.8)%, 43.2 (6.6) ml · kg−1 · min−1, respectively] performed light intermittent exercise (repeated intervals of 15 min of walking at 4.0 km · h−1 followed by 15 min of seated rest) in the heat (40°C, 30% relative humidity) while wearing nuclear, biological, and chemical
protective clothing (0.29 m2 ·°C · W−1 or 1.88 clo, Woodcock vapour permeability coefficient 0.33 i
m). Group F consisted of eight non-users and nine users of oral contraceptives tested during the early follicular phase of
their menstrual cycle. Heart rates were higher for F throughout the session reaching 166.7 (15.9) beats · min−1 at 105 min (n = 13) compared with 145.1 (14.4) beats · min−1 for M. Sweat rates and evaporation rates from the clothing were lower and average skin temperature () was higher for F. The increase in rectal temperature (T
re) was significantly faster for the F, increasing 1.52 (0.29)°C after 105 min compared with an increase of 1.37 (0.29)°C for
M. Tolerance times were significantly longer for M [142.9 (24.5) min] than for F [119.3 (17.3) min]. Partitional calorimetric
estimates of heat storage (S) revealed that although the rate of S was similar between genders [42.1 (6.6) and 46.1 (9.7) W · m−2 for F and M, respectively], S expressed per unit of total mass was significantly lower for F [7.76 (1.44) kJ · kg−1] compared with M [9.45 (1.26) kJ · kg−1]. When subjects were matched for body fatness (n = 8 F and 8 M), tolerance times [124.5 (14.7) and 140.3 (27.4) min for F and M, respectively] and S [8.67 (1.44) and 9.39 (1.05) kJ · kg−1 for F and M, respectively] were not different between the genders. It was concluded that females are at a thermoregulatory
disadvantage compared with males when wearing protective clothing and exercising in a hot environment. This disadvantage can
be attributed to the lower specific heat of adipose versus non-adipose tissue and a higher percentage body fatness.
Accepted: 31 October 1997 相似文献
5.
J. Langfort R. Zarzeczny W. Pilis K. Nazar H. Kaciuba-Ucitko 《European journal of applied physiology and occupational physiology》1997,76(2):128-133
The aim of this study was to find out whether a low-carbohydrate diet (L-CHO) affects: (1) the capacity for all-out anaerobic
exercise, and (2) hormonal and metabolic responses to this type of exercise. To this purpose, eight healthy subjects underwent
a 30-s bicycle Wingate test preceded by either 3 days of a controlled mixed diet (130 kJ/kg of body mass daily, 50% carbohydrate,
30% fat, 20% protein) or 3 days of an isoenergetic L-CHO diet (up to 5% carbohydrate, 50% fat, 45% protein) in a randomized
order. Before and during 1 h after the exercise venous blood samples were taken for measurement of blood lactate (LA), β-hydroxybutyrate
(β-HB), glucose, adrenaline (A), noradrenaline (NA) and insulin levels. Oxygen consumption (V˙O2) was also determined. It was found that the L-CHO diet diminished the mean power output during the 30-s exercise bout [533
(7) W vs 581 (7) W, P < 0.05] without changing the maximal power attained during the first or second 5-s interval of the exercise. In comparison
with the data obtained after the consumption of a mixed diet, after the consumption of a L-CHO diet resting plasma concentrations
of β-HB [2.38 (0.18) vs 0.23 (0.01) mmol · l−1, P < 0.001] and NA [4.81 (0.68) vs 2.2 (0.31) nmol · l−1, P < 0.05] were higher, while glucose [4.6 (0.1) vs 5.7 (0.2) mmol · l−1, P < 0.05] and insulin concentrations [11.9 (0.9) vs 21.8 (1.8) mU · l−1] were lower. The 1-h post-exercise excess of V˙O2 [9.1 (0.25) vs 10.6 (0.25) l, P < 0.05], and blood LA measured 3 min after the exercise [9.5 (0.4) vs 10.6 (0.5) mmol · l−1, P < 0.05] were lower following the L-CHO treatment, whilst plasma NA and A concentrations reached higher values [2.24 (0.40) vs
1.21 (0.13) nmol · l−1 and 14.30 (1.41) vs 8.20 (1.31) nmol · l−1, P < 0.01, respectively]. In subjects on the L-CHO diet, the plasma β-HB concentration decreased quickly after exercise, attaining
≈30% of the pre-exercise value within 60 min, while insulin and glucose levels were elevated. The main conclusions of this
study are: (1) a L-CHO diet is detrimental to anaerobic work capacity, possibly because of a reduced muscle glycogen store
and decreased rate of glycolysis; (2) reduced carbohydrate intake for 3 days enhances activity of the sympathoadrenal system
at rest and after exercise.
Accepted: 31 January 1997 相似文献
6.
Jaak Jürim?e Peter J. Abernethy B. M. Quigley Kirsten Blake Michael T. McEniery 《European journal of applied physiology and occupational physiology》1997,75(4):357-362
The purpose of this investigation was to compare the myosin heavy chain (MHC) isoform expression of the triceps brachii muscle
and isoinertial, isometric and isokinetic strength indices in competitive bodybuilders (CB, n = 5), recreational resistance trainers (RT, n = 5), endurance-trained rowers (ER, n = 5) and control (C, n = 5) subjects. Muscle tissue samples were analysed for MHC isoform content using 6% sodium dodecyl sulphate-polyacrylamide
gel electrophoresis. The CB possessed significantly smaller (P < 0.05) percentage of MHC type IIb proteins [12.92 (SD 7.08)%] than RT [30.08 (SD 6.58)%] ER [31.20 (SD 2.74)%] and C [38.22
(SD 2.95)%] groups (i.e. CB < RT ≈ ER < C). While the content of MHC type IIa isoforms did not differ significantly between
the two resistance-trained groups [CB = 55.76 (SD 5.38)%; RT = 45.72 (SD 7.8)%], CB presented significantly more type IIa
MHC isoforms than ER [42.84 (SD 2.98)%] and C [34.72 (SD 1.57)%] subjects (i.e. CB ≈ RT > ER ≈ C). The MHC type I protein
content did not differ significantly among RT [24.20 (SD 4.89)%] ER [25.38 (SD 1.67)%] and C [27.06 (SD 1.81)%] groups. The
CB [31.32 (SD 2.67)%] presented significantly more type I MHC isoforms only in comparison with RT. However, when changes in
the percentage of MHC type I isoforms were converted to effect sizes (ES), it appeared that low statistical power rather than
the absence of an effect accounted for the nonsignificant differences between CB and other groups (i.e. CB > RT ≈ ER ≈ C).
Significant differences existed in isoinertial strength among the trained athletes (i.e. CB > RT > ER ≈ C), while isometric
and isokinetic strength were not significantly different among any of the trained groups. However, the ES transformation of
data demonstrated that large differences existed between resistance-trained groups and ER for isometric and isokinetic strength
(i.e. CB ≈ RT > ER ≈ C). A statistically significant negative correlation (P < 0.001) was found between MHC type IIb isoforms and isoinertial strength index (r = − 0.68). The MHC type IIa proteins were positively related to all the strength measures considered (r = 0.51 – 0.61; P < 0.001). These data demonstrated different patterns of MHC isoform expression among the different groups of athletes and
it is suggested that these differences on occasion may affect the expression of strength.
Accepted: 24 September 1996 相似文献
7.
Schistosoma mansoni cercarial glycolipids are dominated by Lewis X and pseudo-Lewis Y structures 总被引:1,自引:0,他引:1
The oligosaccharide structures of glycolipids from cercariaeof the human blood fluke, Schistosoma mansoni, were analyzedin the form of their corresponding, pyridylaminated oligosaccharidesby methylation analysis, partial hydrolysis, exoglycosidasetreatment, on-target exoglycosidase cleavage and matrix-assistedlaser desorption/ionization time-of-flight mass spectrometry.The six, dominant chemical structures present have been determinedas: GalNAc(ß14)Glc1-ceramide; GlcNAc(ß13)GalNAc(ß14)Glc1-ceramide;Gal(ß14)GlcNAc(ß13)GalNAc(ß14)Glc1-ceramide;Gal(ß14)[Fuc( 相似文献
8.
Protective effects of selenium against mercury toxicity have been demonstrated in all animal models evaluated. As interactions
between selenium and mercury and their molar ratios in seafood are essential factors in evaluating risks associated with dietary
mercury exposure, considering mercury content alone is inadequate. In this study, the absolute and molar concentrations of
mercury and selenium were determined in edible portions from 420 individual fish representing 15 species of pelagic fish collected
from the central North Pacific Ocean near Hawaii. Selenium was in molar excess of mercury in almost all fish species evaluated.
The rank order of mean Se/Hg molar ratios was striped marlin (17.6) > yellowfin tuna (14.1) > mahimahi (13.1) > skipjack tuna
(12.8) > spearfish (11.4) > wahoo (10.8) > sickle pomfret (6.7) > albacore tuna (5.3) > bigeye tuna (5.2) > blue marlin (4.1) > escolar
(2.4) > opah (2.3) > thresher shark (1.5) > swordfish (1.2) > mako shark (0.5). With a Se/Hg molar ratio of less than 1, mako
shark was the only fish containing a net molar excess of mercury. A selenium health benefit value based on the absolute amounts
and relative proportions of selenium and mercury in seafood is proposed as a more comprehensive seafood safety criterion. 相似文献
9.
Ioannis G. Fatouros Allan H. Goldfarb Athanasios Z. Jamurtas Theodore J. Angelopoulos Jiaping Gao 《European journal of applied physiology and occupational physiology》1997,76(3):203-208
β-Endorphin (BE) infusion at rest can influence insulin and glucagon levels and thus may affect glucose availability during
exercise. To clarify the effect of BE on levels of insulin, glucagon and glucose during exercise, 72 untrained male Sprague-Dawley
rats were infused i.v. with either: (1) BE (bolus 0.05 mg · kg−1 +0.05 mg · kg−1 · h−1, n = 24); (2) naloxone (N, bolus 0.8 mg · kg−1 + 0.4 mg · kg−1, n = 24); or (3) volume-matched saline (S, n = 24). Six rats from each group were killed after 0, 60, 90 or 120 min of running at 22 m · min−1, at 0% gradient. BE infusion resulted in higher plasma glucose levels at 60 min [5.93 (0.32) mM] and 90 min [4.16 (0.29) mM]
of exercise compared to S [4.62 (0.27) and 3.41 (0.26 mM] and N [4.97 (0.38) and 3.44 (0.25) mM]. Insulin levels decreased
to a greater extent with BE [21.5 (0.9) and 18.3 (0.6) uIU · ml−1] at 60 and 90 min compared to S [24.5 (0.5) and 20.6 (0.6) uIU · ml−1] and N [24.5 (0.4) and 21.6 (0.7) uIU · ml−1] groups. Plasma C-peptide declined to a greater extent at 60 and 90 min of exercise with BE infusion compared to both S and
N. BE infusion increased glucagon at all times during exercise compared to S and N. These data suggest that BE infusion during
exercise influences plasma glucose by augmenting glucagon levels and attenuating insulin release.
Accepted: 26 February 1997 相似文献
10.
11.
Nie H Li Z Lukas RJ Shen Y Song L Wang X Yin M 《Cellular and molecular neurobiology》2008,28(1):103-112
(1) Nicotinic acetylcholine receptors in central nervous system are thought to be new targets for Alzheimer’s disease. However,
the most involved nicotinic receptor subtype in Alzheimer’s disease is unclear. α4β2 receptor is the most widely spread subtype
in brain, involving in several important aspects of cognitive and other functions. We constructed cell line by transfecting
human amyloid precursor protein (695) gene into SH-EP1 cells which have been transfected with human nicotinic receptor α4
subunit and β2 subunit gene, to observe effects of α4β2 receptors activation on β-amyloid, expecting to provide a new cell
line for drug screening and research purpose. (2) Liposome transfection was used to express human amyloid precursor protein
(695) gene in SH-EP1-α4β2 cells. Function of the transfected α4β2 receptors was tested by patch clamp. Effects of nicotine
and epibatidine (selective α4β2 nicotinic receptor agonist) on β-amyloid were detected by Western blot and ELISA. Effects
of nicotine and epibatidine on amyloid precursor protein (695) mRNA level were measured using real-time PCR. (3) Human amyloid
precursor protein (695) gene was stably expressed in SH-EP1-α4β2 cells; Nicotine (1 μM) and epibatidine (0.1 μM) decreased
intracellular and secreted β-amyloid in the cells; and activation of α4β2 receptors did not affect amyloid precursor protein
(695) mRNA level. (4) These results suggest that the constructed cell line, expressing both amyloid precursor protein (695)
gene and human nicotinic receptor α4 subunit and β2 subunit gene, might be useful for screening specific nicotinic receptor
agonists against Alzheimer’s disease. Alteration of Aβ level induced by activation of α4β2 nAChR in our study might occur
at a post-translational level. 相似文献
12.
John A. Hawley Garry S. Palmer Timothy D. Noakes 《European journal of applied physiology and occupational physiology》1997,75(5):407-412
This study compared the effects of supplementing the normal diets of six trained cyclists [maximal oxygen uptake O2max) 4.5 (0.36)l · min−1; values are mean (SD)] with additional carbohydrate (CHO) on muscle glycogen utilisation during a 1-h cycle time-trial (TT).
Using a randomised crossover design, subjects consumed either their normal diet (NORM) for 3 days, which consisted of 426
(137) g · day−1 CHO [5.9 (1.4) g · kg−1 body mass (BM)], or additional CHO (SUPP) to increase their intake to 661 (76) g · day−1 [9.3 (0.7) g · kg−1 BM]. The SUPP diet elevated muscle glycogen content from 459 (83) to 565 (62) mmol · kg−1 dry weight (d.w.) (P < 0.05). However, despite the increased pre-exercise muscle glycogen stores, there was no difference in the distance cycled
during the TT [40.41 (1.44) vs 40.18 (1.76) km for NORM and SUPP, respectively]. With NORM, muscle glycogen declined from
459 (83) to 175 (64) mmol · kg−1 d.w., whereas with SUPP the corresponding values were 565 (62) and 292 (113) mmol · kg−1 d.w. Accordingly, both muscle glycogen utilisation [277 (64) vs 273 (114) mmol · kg−1 d.w.] and total CHO oxidation [169 (20) vs 165 (30) g · h−1 for NORM and SUPP, respectively] were similar. Neither were there any differences in plasma glucose or lactate concentrations
during the two experimental trials. Plasma glucose concentration averaged 5.5 (0.5) and 5.6 (0.6) mmol · l−1, while plasma lactate concentration averaged 4.4 (1.9) and 4.4 (2.3) mmol · l−1 for NORM and SUPP, respectively. The results of this study show that when well-trained subjects increase the CHO content
of their diet for 3 days from 6 to 9 g · kg−1 BM there is only a modest increase in muscle glycogen content. Since supplementary CHO did not improve TT performance, we
conclude that additional CHO provides no benefit to performance for athletes who compete in intense, continuous events lasting
1 h. Furthermore, the substantial muscle CHO reserves observed at the termination of exercise indicate that whole-muscle glycogen
depletion does not determine fatigue at this exercise intensity and duration.
Accepted: 25 November 1996 相似文献
13.
Evstaf’yeva E. V. Zalata O. A. Evstaf’yeva I. A. shchegoleva M. G. 《Neurophysiology》2011,43(3):258-260
In 10- to 16-year-old children, inhabitants of industrial towns of Ukraine, an X-ray fluorescence analysis of the content
of some chemical elements in hair samples allowed us to find a deficiency of Zn and Cu against the background of excesses
of Ca, Cr, Ni, Mo, and Cd. Comparison of the parameters of EEG frequency components and levels of Ca, Zn, Cu, Fe, Mn, Co,
Cr, Mo, Ni, Sr, Pb, and Cd showed that there are significant correlations between the normalized values of spectral powers
of many frequency components of the ongoing EEG recorded in different functional states (eyes closed/open, solving an arithmetic
task, and phono-/photostimulation) and concentrations of ten of the above-mentioned trace elements. Comparative estimation
of the neurotropicity of the elements showed the following sequence of numbers of significant correlations (shown in parentheses)
from the total set of possible comparisons: Cd (35) > Ni (31) > Cr (19) > Sr (17) > Pb (16) > > Ca (10) > Cu (7) > Mo (3) > Zn
(2) > Fe (1). The intensity of correlations (values of the correlation coefficients) varied from 0.26 to 0.42 at 0.05 < P < 0.001; more frequently, such correlations were observed under conditions of EEG recording with the eyes closed (39) and
upon solving an arithmetic task (33). 相似文献
14.
Peter R. Andreana Przemyslaw Kowal Adam J. Janczuk Peng George Wang 《Glycoconjugate journal》2003,20(2):107-118
Galactose oxidase (EC 1.1.3.9, GAO) was used to convert the C-6′ OH of Galβ(1 → 4)Glcβ–OBn (5) to the corresponding hydrated
aldehyde (7). Chemical modification, through dehydratative coupling and reductive amination, gave rise to a small library
of Galβ(1 → 4)Glcβ–OBn analogues (9a–f, 10, 11). UDP-[6-3H]Gal studies indicated that α1,3-galactosyltransferase recognized the C-6′ modified Galβ(1 → 4)Glcβ–OBn analogues (9a–f,
10, 11). Preparative scale reactions ensued, utilizing a single enzyme UDP-Gal conversion as well as a dual enzymatic system
(GalE and α1,3GalT), taking full advantage of the more economical UDP-Glc, giving rise to compounds 6, 15–22. Galα(1 → 3)Galβ(1
→ 4)Glcβ–OBn trisaccharide (6) was produced on a large scale (2 g) and subjected to the same chemoenzymatic modification as
stated above to produce C-6″ modified derivatives (23–30). An ELISA bioassay was performed utilizing human anti-αGal antibodies
to study the binding affinity of the derivatized epitopes (6, 15–30). Modifications made at the C-6′ position did not alter
the IgG antibody's ability to recognize the unnatural epitopes. Modifications made at the C-6″ position resulted in significant
or complete abrogation of recognition. The results indicate that the C-6′ OH of the αGal trisaccharide epitope is not mandatory
for antibody recognition. Published in 2004.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
Hilde Spielvogel Armando Rodriguez Brigitte Sempore Esperanza Caceres J.-M. Cottet-Emard Laurent Guillon R. Favier 《European journal of applied physiology and occupational physiology》1997,75(5):400-406
The present study was undertaken to determine the haematological and cardiovascular status, at rest and during prolonged
(1 h) submaximal exercise (approximately 70% of peak oxygen uptake) in a group (n = 12) of chronic coca users after chewing approximately 50 g of coca leaves. The results were compared to those obtained
in a group (n = 12) of nonchewers. At rest, coca chewing was accompanied by a significant increase in heart rate [from 60 (SEM 4) TO 76 (SEM 3)
beats · min−1], in haematocrit [from 53.2 (SEM 1.2) to 55.6 (SEM 1.1)%] in haemoglobin concentration, and plasma noradrenaline concentration
[from 2.8 (SEM 0.4) to 5.0 (SEM 0.5) μmol · l−1]. It was calculated that coca chewing for 1 h resulted in a significant decrease in blood [−4.3 (SEM 2.2)%] and plasma [−8.7 (SEM 1.2)%]
volume. During submaximal exercise, coca chewers displayed a significantly higher heart rate and mean arterial blood pressure.
The exercise-induced haemoconcentration was blunted in coca chewers compared to nonchewers. It was concluded that the coca-induced
fluid shift observed at rest in these coca chewers was not cumulative with that of exercise, and that the hypovolaemia induced
by coca chewing at rest compromised circulatory adjustments during exercise.
Accepted: 29 October 1996 相似文献
16.
Lipopolysaccharides (LPSs) of two strains Pragia fontium 97U116 and 27480 were isolated and characterized; they were close to those of other representatives of the family Enterobacteriaceae in fatty acid composition and contained, respectively, 3-hydroxytetradecanoic acid as the predominant component (45.8 and 45.1%), tetradecanoic (23.5 and 28.9%), hexadecanoic (12.6 and 7.9%), hexadecenoic (12.6 and 7.9%), and dodecanoic (4.9 and 4.2%) fatty acids. The O-specific polysaccharides consisted of linear penta- and tetrasaccharide repeating units: →2)-α-D-Galf-(1→3)-α-L-Rhap2Ac-(1→4)-α-D-GlcpNAc-(1→2)-α-L-Rhap-(1→3)-β-D-GlcpNAc-(1→ →4)-β-D-ManpNAc3NAcA-(1→2)-α-L-Rhap-(1→3)-β-L-Rhap-(1→4)-α-D-GlcpNAc-(1→ The LPSs of P. fontium 97U116 and 27480 were serologically active and belonged to different serogroups; they were less toxic than those of strain E. coli O55:B5, but more pyrogenic than the Pyrogenal preparation. 相似文献
17.
The effect of pulse repetition rate, pulse intensity, and bicuculline on the minimum threshold and latency of bat inferior collicular neurons 总被引:2,自引:0,他引:2
P. H.-S. Jen Q.-C. Chen 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1998,182(4):455-465
This study examines the effect of pulse repetition rate (PRR), pulse intensity, and bicuculline on the minimum threshold (MT)
and latency of inferior collicular neurons of the big brown bat, Eptesicusfuscus, under free-field stimulation conditions. It tests the hypothesis that changes in MT and latency of collicular neurons are
co-dependent on PRR. The number of impulses in inferior collicular neurons (n = 245) increased either monotonically (25%) or non-monotonically (75%) with pulse intensity. Latencies either decreased to
a plateau (72%), fluctuated unpredictably within 3 ms (21%) or changed very little (7%) with increasing pulse intensity. Latencies
and MTs of most collicular neurons increased by 1.5–24 ms (mean ± SD = 4.8 ± 3.3 ms) and 4–75 dB (mean ± SD = 22.1 ± 16.2 dB)
with increasing PRR. In most neurons (94%), the latency increase was completely (42%) or partially (52%) eliminated when pulse
intensity was compensated for the MT increase with PRR. Complete elimination of latency was achieved by bicuculline application.
In a few neurons (6%), the latency increase with PRR was not affected by compensated pulse intensity or bicuculline application.
Accepted: 8 October 1997 相似文献
18.
Watanabe A Shimokawa T Moriyama M Komine F Amaki S Arakawa Y Ra C 《Immunogenetics》2006,58(12):937-946
Fc receptor for IgA (FcαR, CD89) is capable of triggering IgA-mediated immune responses to pathogens and has been proposed to function in circulating IgA clearance. Because inheritable variations modifying individual immune responses or immunoglobulin catabolism may affect the chronicity of viral infection, we investigated whether promoter polymorphisms of the FcαR gene (FCAR) affect chronic hepatitis C virus (HCV) infection and its disease progression. The two −311T/C and −142T/C single-nucleotide polymorphisms (SNPs) were studied by direct DNA sequencing in 177 Japanese patients with chronic hepatitis C (CHC). Both −311CC and −142CC genotypes were more frequent in CHC patients (15.9 and 18.6%) compared with 210 healthy controls (5.7 and 10.0%) [p = 0.001, odds ratio (OR) = 3.10, 95% confidence interval CI) = 1.53–6.30 and p = 0.014, OR = 2.06, 95% CI = 1.14–3.72, respectively], and were associated with infection with HCV genotype 2a/2b (p = 0.019 and p = 0.005, respectively). Conversely, −311CC and −142CC were decreased in 59 patients at advanced stages of disease as assessed on the basis of hepatic fibrosis markers such as decreased platelet count (PLT) ( < 150,000/μl) (5.1 and 8.5%) compared with 91 patients with normal PLT ( ≥ 150,000/μl) (24.2 and 26.4%) (p = 0.006 and p = 0.005, respectively). Moreover, among the patients with normal PLT (but not with decreased PLT), −311CC or −142CC was significantly associated with decreased serum IgA levels (p = 0.023 or p = 0.007, respectively). These results suggest that the FCAR promoter SNPs may be related to chronic HCV infection and disease progression in Japanese CHC, which might be explained by altered FcαR expression affecting IgA-mediated immune responses and/or IgA catabolism. 相似文献
19.
Dayangku Fatiha Pengiran Burut Anwar Borai Callum Livingstone Gordon Ferns 《Cell stress & chaperones》2010,15(4):379-386
Heat shock protein 27 (Hsp27) is over-expressed when cells are exposed to stressful conditions that include oxidative stress.
Oxidative stress has been implicated in the pathogenesis of cardiovascular disease (CVD), diabetes and insulin resistance.
We have investigated the concentrations of serum Hsp27 antigen and antibodies in subjects from different glycaemic categories,
who either did or did not have established CVD. Serum Hsp27 antigen and antibody levels (immunoglobulins M and G (IgM and
IgG)) were determined by enzyme-linked immunosorbent assays (ELISAs) in 68 individuals: 26 with normal glucose tolerance (NGT),
10 with (+) and 16 without (−) a history of CVD and 42 individuals with varying degrees of glucose intolerance (GI; 21 with
and 21 without a history of CVD). Insulin sensitivity was determined in each subject using indices derived from the homeostasis
model assessment of sensitivity and the insulin sensitivity index for glycaemia. Serum Hsp27 concentrations were significantly
higher in GI (+CVD) subjects compared to GI (−CVD) subjects (p = 0.03), NGT (−CVD) subjects (p = 0.02) and NGT (+CVD) subjects (p = 0.04) and were positively correlated to fasting plasma glucose for all subjects (r = 0.28, p = 0.03). IgM antibody levels were significantly higher in GI (+CVD) subjects compared to NGT (−CVD) group (p = 0.02) and were inversely related to fasting insulin concentrations (r = −0.27, p = 0.04) and the 2-h insulin concentrations (r = −0.29, p = 0.03) for all subjects. Serum IgG antibody levels were higher in GI (+CVD) group compared to GI (−CVD) group (p = 0.06). In conclusion, Hsp27 and its antibody concentrations appear to relate to the presence of cardiovascular complications
in patients with GI. 相似文献
20.
A pioneering limnological investigation was carried out in Bhutan in a small peat bog in the Trashiyangtse district (1950 m
above sea level) from February 2000 to January 2002. The sampled pond water had low transparency (55.0–95.0 cm), was typically
acidic (pH 5.69–6.58) with soft water (alkalinity, 11.0–36.0 mg/l; total hardness, 10.0–34.0 mg/l), and had low to moderate
specific conductivity (17.0–62.0 μS/cm). Further, moderate Na (2.0–6.8 mg/l), K (1.8–13.5 mg/l), sulphate (0.85–2.99 mg/l),
and silicate (2.5–15.0 mg/l) concentrations as well as low nutrient levels such as phosphate (0.006–0.170 mg/l) and nitrate
(0.003–0.180 mg/l) characterize the water in the peat bog. The recorded net plankton comprised 27 species of phytoplankton
and 49 species of zooplankton, with the latter indicating greater homogeneity and breaking down into Rotifera (23 species)
> Cladocera (13 species) > Rhizopoda (8 species) > Copepoda (3 species) > Ostracoda = Nematoda (1 species each). On the other
hand, the net plankton density ranged between 93 and 692 number/l (n/l) with numerical dominance by phytoplankton (68.5% ±
12%), of which Chlorophyceae were predominant (90 ± 63 n/l). Zooplankton showed moderately high diversity (2.745 ± 0.293)
and evenness (0.925 ± 0.049) and exhibited almost equal abundance of four recorded groups, namely Cladocera (20 ± 15 n/l)
> Rotifera (15 ± 6 n/l) > Copepoda (14 ± 7 n/l) > Rhizopoda (14 ± 4 n/l). While no significant impact of abiotic factors was
recorded on zooplankton density, rainfall alone was the most important factor that influenced net plankton and various groups
of phytoplankton. Comments on some comparative limnological attributes are also made with similar as well as different habitats
in the nearby Himalayan countries. 相似文献