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1.
The effects of ketamine anesthesia on both hematological and serum biochemical variables were investigated in 19 male and 15 female cynomolgus monkeys. Blood samples were obtained from the cephalic vein within 30 minutes of an intramuscular injection of ketamine hydrochloride (10 mg/kg). Ketamine anesthesia caused a reduction in leukocyte counts and a significant reduction in lymphocytes percentages. Ketamine anesthesia also increased the serum activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatine phosphokinase (CPK), but reduced the serum concentrations of glucose, inorganic phosphate, sodium and potassium. The alterations of hematological and serum biochemical values will be discussed. These alterations should be considered when designing studies for and interpreting data from cynomolgus monkeys.  相似文献   

2.
BACKGROUND AND METHODS: Quantitative enzyme-immunoassays of urinary and fecal immunoglobulin A (IgA), cortisol and 11-17-dioxoandrostanes (11,17-DOA), and serum cortisol in eight metabolic-cage-housed female cynomolgus monkeys were performed. The monkeys were divided into two groups, B and NB. Group B animals were blood sampled every 6 hours, whereas Group NB animals were not handled/blood sampled. RESULTS: No differences were recorded between the amounts of feces and urine excreted by the two groups. Group B animals excreted more urinary cortisol than did Group NB animals indicating that restraint-blood sampling resulted in a stress response. Excreted amounts of IgA and 11,17-DOA (urine and feces) did not differ between the groups. CONCLUSIONS: Urinary cortisol was a reliable marker of the stress associated with repeated blood sampling. Declining amounts of excreted urinary cortisol indicated that cynomolgus monkeys acclimated quickly to repeated blood sampling in metabolism cages. Within and between animal variation in amounts of feces voided demonstrated the importance of expressing fecal markers as 'amounts excreted per time unit per kg body weight' rather than just measuring the concentrations in fecal samples.  相似文献   

3.
4.
Optimal conditions for the mitogen-induced proliferation of T and B lymphocytes of cynomolgus monkeys were determined. The T cell mitogens concanavalin A and phytohemagglutinin, at concentrations of 1.25–10 μg/ml and 1.25–10 μg/ml, respectively, and the T and B cell mitogen pokeweed mitogen, at concentrations of 0.2–10 μg/ml, induced high lymphoproliferative responses, the average stimulation index (SI) being 34–93. Since suitable mitogens have not been reported for monkey B cells, we tested three types of lipopolysaccharide (LPS): two derived from Escherichia coli—one extracted with phenol and one extracted with trichloroacetic acid (TCA); and one derived from Salmonella typhimurium, extracted with phenol. All three LPS had a high mitogenic effect for monkey lymphocytes, with SI of 2.3–6.4. The highest response was observed for 25 μg/ml of Salmonella LPS, and the addition of trypsin to the culture augmented the proliferative response of low or non-responder lymphocytes. © 1994 Wiley-Liss, Inc.  相似文献   

5.
The objective of this study was to look for early pathological changes in stress target organs, adrenal glands, and stomachs in captured wild African green monkeys (AGMs). Three wild-caught male AGMs and seven singly housed wild AGMs were euthanized on day 1 and day 45 post-capture, respectively, and compared with four wild males euthanized with a rifle as controls. Morphometric analyses of the adrenal cortices and the cortical zones were done using an image analyzer. By day 45, the confined animals were clinically healthy, but had lost 47% mean body weight despite ad libitum feeding. The width of zona fasciculata in the controls was significantly smaller compared with that of 45-day monkeys (P < 0.05). Numerous acidophilic, hyperplastic and hypertrophic cells were present in the zona fasciculata of the 1-day confined AGMs. In the 45-day monkeys, there was glandular hyperplasia in the zona glomerulosa and the acini were distended and vacuous; yellow, granular pigmentation was distributed in the zona fasciculata. Acute stomach lesions represented by petechiation were seen in one monkey on day 1. Deep, circular, mucosal erosions, one to five in number and measuring from 0.5 to 1 mm in diameter, were present in three monkeys on day 45 post-capture. There were no adrenal cortex or stomach lesions in the rifle-shot monkeys. In conclusion, pathological lesions in the adrenal glands, and stomachs of the wild AGMs and weight loss occurred within the initial 45-day period following capture and confinement.  相似文献   

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7.
Exposure of isolated chloroplasts of pea (Pisum sativum L.) to temperatures above 35° C leads to a stimulation of photosystem-I-mediated electron transport from dichlorophenolindophenol to methyl viologen. The threshold temperature for this stimulation coincides closely with that for heat-induced inhibition of photosystem-II activity in such chloroplasts. This coincidence is explained in terms of a rearrangement of the thylakoid membrane resulting in the exposure of a new set of donor sites for dichlorophenolindophenol within the cytochrome f/b 6 complex of the electron-transport chain linking the two photosystems.Abbreviations cyt cytochrome - DBMIB 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone - DCPIP (H2) 2,6-dichlorophenolindophenol - EDAC ethyldimethylaminopropyl-carbodiimide - MV methyl viologen - PSI, II photosystem I, II - PCy plastocyanin - PQ(H2) plastoquinone  相似文献   

8.

A, net CO2 assimilation rate
E, leaf transpiration
ETR, electron transport rate
Fs, fluorescence yield at steady state
Fm and Fm', maximal fluorescence levels when all PSII reaction centres are closed in dark- and light-acclimated leaves, respectively
Fo and Fo', initial fluorescence levels when all PSII reaction centres are closed in dark- and light-acclimated leaves, respectively
Fv/Fm, efficiency of excitation capture by open PSII in dark-adapted leaves
ΔF/Fm', actual photochemical efficiency of PSII
g, stomatal conductance
NPQ, non-photochemical quenching of chlorophyll fluorescence
PPFD, photosynthetic photon flux density
ΨPD and ΨMD, leaf water potential at pre-dawn and midday, respectively
Rl, estimated photorespiration rate
I1 and I2, Irrigation treatments
R, Recovery treatment
D1 and D2, drought treatments
HD1 and HD2, hard drought treatments

Diurnal time courses of chlorophyll fluorescence and gas-exchange rates were measured in young potted grapevines (Vitis vinifera L. cv. Tempranillo) subjected to different conditions of water supply under Mediterranean summer conditions. The irrigated plants exhibited typical diurnal patterns for all measured parameters, showing a correspondence between electron transport rate, net CO2 assimilation and stomatal conductance. Mild decreases in soil-water availability led to different degrees of down-regulation of photosynthesis and increased nonphotochemical quenching of chlorophyll fluorescence. A good correspondence between electron transport rate and CO2 assimilation was still maintained, suggesting a coregulation of both photosynthetic processes. In contrast, a severe water deficit induced a drastic down-regulation of photosynthesis and breakage of the above-mentioned link. Both midday net CO2 assimilation and electron transport rate significantly correlated with pre-dawn water potential (ΨPD) (r2 = 0·65 and r2 = 0·92, P < 0·001, respectively). However, when field data were analysed, the relationship between electron transport rate and ΨPD was not maintained, although net CO2 assimilation was similarly correlated with ΨPD. Interestingly, the steady-state chlorophyll fluorescence yield was a good indicator of plant water stress.  相似文献   

9.
Sulfate uptake by Saccharomyces cerevisiae is stimulated about 12-fold by preincubation of cells with 1% d-glucose or 1% ethanol. The KT remains unchanged (0.34–0.38 mM), the Jmar increase from 18–20 to 195–230 and 170–185 nmol/min per g dry wt., respectively, after glucose and ethanol preincubation. The stimulation involves protein synthesis (it is suppressed by cycloheximide), has a half-time of 18 min and requires mitochondrial respiration (no or low effect in respiration-deficient mutants and those lacking ADP-ATP transport in mitochondria, as well as after anaerobic preincubation of the wild-type strain, and in low-phosphate cells). The presence of NH4+ and some amino acids (e.g., leucine, aspartate, cysteine and methionine) depressed the stimulation while that of cationic amino acids (typically arginine and lysine) and of K+ increased it by 50–80%. The stimulated (i.e., newly synthesized) transport system was degraded with a half-life of about 10 min.  相似文献   

10.
This study was designed to investigate the effects of Nigella sativa L. (NS), known as black seed, or/and Urtica dioica L. (UD), known as stinging nettle root, treatments on serum Na, K, Cl, and Ca levels and some hematological values of CCl4-treated rats. Sixty healthy male Sprague-Dawley rats, weighing 250–300 g, were randomly allotted into 1 of 4 experimental groups: A (CCl4-only treated), B (CCl4+UD treated), C (CCl4+NS treated), and D (CCl4+UD+NS treated), each containing 15 animals. All groups received CCl4 (0.8 mL/kg of body weight, subcutaneously, twice a week for 90 d starting d 1). In addition, B, C, and D groups also received the daily ip injection of 0.2 mL/kg NS and/or 2 mL/kg UD oils for 45 d starting d 46. Group A, on the other hand, received only 2 mL/kg normal saline solution for 45 d starting d 46. Blood samples for the biochemical analysis were taken by cardiac puncture from five randomly chosen rats in each treatment group at the beginning, d 45, and d 90 of the experiment. The CCl4 treatment for 45 d significantly (p<0.05) increased the serum K and Ca and decreased (p<0.05) the red blood cell count (RBC), white blood cell count (WBC), packed cell volume (PCV), and Hb levels without changing (p>0.05) the serum Na and Cl levels. NS or UD treatments (alone or combination) for 45 d starting d 46 significantly (p<0.05) decreased the elevated serum K and Ca levels and also increased (p<0.05) the reduced RBC, WBC, PCV, and Hb levels. It is concluded that NS and/or UD treatments might ameliorate the CCl4-induced disturbances of anemia, some minerals, and body’s defense mechanism in CCl4-treated rats.  相似文献   

11.
Background The objective of this study was to evaluate the role of the adrenal cortex in the regulation of antioxidant enzyme defense and to characterize this regulation in different age periods. Methods Five young and five old female rhesus monkeys were subjected to 2 hours squeeze cage restraint stress at 0900 or 1500 hours. Plasma levels of corticosteroids and activities of erythrocyte antioxidant enzymes were measured before the stress and 30, 60, 120, 240 minutes after beginning of the stress. Results Young monkeys showed a circadian rhythm in stress responsiveness as measured by corticosteroids and glutathione reductase. The rhythm was attenuated in old animals. Age‐related changes in the overall level of response to the afternoon stress were also seen in the corticosteroid and glutathione reductase measures. Conclusions The study demonstrated that corticosteroids play an essential role in the regulation of antioxidant enzyme defense in stress conditions and that the reliability of their regulation decreases with age.  相似文献   

12.
This study introduces a new class of active-site directed probes with respect to ADP and ATP transport catalysis in rat liver mitochondria. The anionic monoazo dyes, e.g., p-(2-hydroxy-1-naphthylazo)naphtholsulfonic acid, are competitive inhibitors of carrier-mediated ADP uptake (Ki 20–30 μM). The azo dyes also can displace the same amount of carrier-specific bound ADP as does carboxyatractyloside. Two essential substructures could be derived from a structure-activity study. Firstly, a sulfonic acid group in the para position relative to the azo bridge which becomes neutralized upon binding by a specifically located positive charge of the carrier protein. This electrostatic binding component, which presumably is represented by a strategic arginyl residue, seems to be essential for substrate binding as well as inhibitor binding. The second structural requirement for effective inhibition was found to be the o-hydroxy or o,o′-dihydroxyazo system, which is known to form stable complexes with metal ions by chelation. Experiments on prevention and reversal of dye-mediated inhibition revealed that the metal-chelating properties are responsible for the effects observed. In addition, using bovine serum albumin or the synthetic polymer Kollidone, inhibition could be prevented as well as abolished. It is postulated that a metal ion, possibly Mg2+, which is bound to the carrier protein plays an essential role for transport catalysis. The metal ion is assumed to form a functional ternary complex, i.e., a metal bridge complex between the carrier protein and its substrate.  相似文献   

13.
In unfertilized eggs, the mechanism of valine uptake can be summarized as follows. It is saturable over the external concentration of valine and insensitive to the presence of external sodium, depletion of cellular energy supplies and intracellular acidosis. The activation energy for the transport reaction (16.3 kcal/mol) is within the range of values reported for active transport of small molecules. In fertilized eggs, the total rate of valine uptake can be divided into two components: (i) a Na+-insensitive uptake which accounts for about 7% of total absorption as shown by studies in Na+-free medium seems to possess the same characteristics as in unfertilized eggs, (ii) a Na+-dependent transport of valine which constitutes the main entry is formed about 5 min after fertilization. It follows Michaelis-Menten kinetics characterized by 15-fold increase in Vmax with no change in Km. These two mechanisms have characteristics in common, such as their insensitivity to metabolic energy supply, their energy of activation and their ability to concentrate valine. The relationship between the establishment of the Na+-dependent valine uptake and the ionic events triggered by fertilization is discussed.  相似文献   

14.
15.
The properties of carnitine transport were studied in rat kidney cortex slices. Tissue: medium concentration gradients of 7.9 for L-[methyl-14C]carnitine were attained after 60-min incubation at 37°C in 40 μM substrate. L- and D-carnitine uptake showed saturability. The concentration curves appeared to consist of (1) a high-affinity component, and (2) a lower affinity site. When corrected for the latter components, the estimated Km for L-carnitine was 90 μM and V = 22nmol/min per ml intracellular fluid; for D-carnitine, Km = 166 μM and V = 15 nmol/min per ml intracellular fluid. The system was stereospecific for L-carnitine. The uptake of L-carnitine was inhibited by (1) D-carnitine, γ-butyrobetaine, and (2) acetyl-L-carnitine. γ-Butyrobetaine and acetyl-L-carnitine were competitive inhibitors of L-carnitine uptake. Carnitine transport was not significantly reduced by choline, betaine, lysine or γ-aminobutyric acid. Carnitine uptake was inhibited by 2,4-dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone, N2 atmosphere, KCN, N-ethylmaleimide, low temperature (4°C) and ouabain. Complete replacement of Na+ in the medium by Li+ reduced L- and D-carnitine uptake by 75 and 60%, respectively. Complete replacement of K+ or Ca2+ in the medium also significantly reduces carnitine uptake. Two roles for the carnitine transport system in kidney are proposed: (1) a renal tubule reabsorption system for the steady-state maintenance of plasma carnitine; and (2) maintenance of normal carnitine levels in kidney cells, which is required for fatty acid oxidation.  相似文献   

16.
Depletion of energy stores of human red cells decreases the maximum transport capacity, Jm, for glucose transport to a value one-third or less of that found in red cells from freshly drawn blood. There is no change in Km. Hemolysis and resealing of red cells with ATP or ADP reverses the decrease in Jm. The maximum effect occurs at concentrations of ATP in the normal range for red cells, however, there is little effect from ADP concentrations in its normal range in freshly drawn red cells. Hemolysis and resealing with ATP gives an increase in Jm and an increase in differential labeling by photolytic labeling with tritiated cytochalasin B. Most of the activation is lost after a second hemolysis-reseal without ATP but about 25% of the activation remains.  相似文献   

17.
18.
Uptake and efflux of 6-deoxy-d-[3H]glucose and of 2-deoxy-d-[14C]glucose by the yeast Kluyveromyces lactis was studied. The tritiated, nonphosphorylatable hexose analogue leaves the cell in the absence and presence of intracellular 2-deoxy-d-glucose 6-phosphate. In energy-rich cells containing pools of hexose 6-phosphate, 2-deoxy-d-glucose is trapped in the cells, for it neither effluxes into glucose-free medium nor exchanges with external, free sugar. In starved, poisoned cells containing negligible amounts of 2-deoxy-d-glucose 6-phosphate, 2-deoxy-d-glucose does leave the cells upon transfer to glucose-free medium. An involvement of analogue structure and availability of metabolites of energy-rich cells in hexose retention is suggested. An internal pool of 6-deoxy-d-glucose does not affect the rate of uptake of 6-deoxy-d-[3H]glucose, nor does internal 2-deoxy-d-[14C]glucose 6-phosphate influence that rate. Hence, transport of glucose by this yeast is probably not regulated by internal pools of glucose 6-phosphate.  相似文献   

19.
Nitrate reduction in roots and shoots and exchange of reduced N between organs were quantitatively estimated in intact 13-d-old seedlings of two-row barley (Hordeum vulgare L. cv. Daisengold) using the 15N-incorporation model (A. Gojon et al. (1986) Plant Physiol. 82, 254–260), except that NH + 4 was replaced by NO - 2 . N-depleted seedlings were exposed to media containing both nitrate (1.8 mM) and nitrite (0.2 mM) under a light-dark cycle of 12:12 h at 20°C; the media contained different amounts of 15N labeling. Experiments were started either immediately after the beginning (expt. 1) or immediately prior to the end (expt. 2) of the light period, and plants were sampled subsequently at each light-dark transition throughout 36 h. The plants effectively utilized 15NO - 3 and accumulated it as reduced 15N, predominantly in the shoots. Accumulation of reduced 15N in both experiments was nearly the same at the end of the experiment but the accumulation pattern in roots and shoots during each 12-h period differed greatly depending on time and the light conditions. In expt. 1, the roots accounted for 31% (light), 58% (dark), and 9% (light) of nitrate reduction by the whole plants, while in expt. 2 the contributions of the root were 82% (dark), 20% (light), and 29% (dark), during each of the three 12-h periods. Xylem transport of nitrate drastically decreased in the dark, but that of reduced N rather increased. The downward translocation of reduced 15N increased while nitrate reduction in the root decreased, whereas upward translocation decreased while nitrate reduction in the shoot increased. We conclude that the cycling of reduced N through the plant is important for N feeding of each organ, and that the transport system of reduced N by way of xylem and phloem, as well as nitrate reduction by root and shoot, can be modulated in response to the relative magnitude of reduced-N demands by the root and shoot, with the one or the other predominating under different circumstances.Symbols Anl accumulation of reduced 15N from 15NO - 3 in 14NO - 3 -fed roots of divided root system - Ar accumulation in root of reduced 15N from 15NO - 3 - As accumulation in shoot of reduced 15N from 15NO - 3 - Rr 15NO - 3 reduction in root - Rs 15NO - 3 reduction in shoot - Tp translocation to root of shoot-reduced 15N from 15NO - 3 in phloem - Tx translocation to shoot of root-reduced 15N from 15NO - 3 in xylem  相似文献   

20.
秦岭川金丝猴一周岁内个体的行为发育   总被引:2,自引:0,他引:2  
2003年3月至2004年5月在陕西周至国家自然保护区的玉皇庙地区,采用目标动物取样法(Focal ani-mal sampling)对2003年出生的5只金丝猴个体行为发育进行了观察,应用全事件记录法(All-occurrences record-ing)进行数据的收集。结果表明23日龄婴儿首次从母亲怀内爬出在树枝上活动,68日龄开始在树上攀爬跳跃,5月龄主动采食树叶和啃投食区食物,6月龄跟随社群迁移。依据婴幼儿主要行为首次出现时间及其变化,把1周岁内个体发育分为5个时期,即完全依赖期、探索外部世界期、融入社群期、适应生存期和逐步独立期。1周岁内婴幼儿活动和休息的地方是母亲怀里、其它个体怀里、树枝上和地面上。随着发育,婴幼儿在这些地方停留的时间也在变化。1周岁内婴幼儿在母亲怀中的时间与年龄存在明显的负相关,在其它个体怀里的时间与年龄也呈显著负相关。虽然独自在树上的时间与年龄相关性不显著,但在地面上停留的时间与年龄呈正相关。  相似文献   

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