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The adrenocortical response of tufted puffin chicks to nutritional deficits.

https://arctichealth.org/en/permalink/ahliterature4742
Source
Horm Behav. 2005 May;47(5):606-19
Publication Type
Article
Date
May-2005
Author
Alexander S Kitaysky
Marc D Romano
John F Piatt
John C Wingfield
Motoshi Kikuchi
Author Affiliation
Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA. ffask@uaf.edu
Source
Horm Behav. 2005 May;47(5):606-19
Date
May-2005
Language
English
Publication Type
Article
Keywords
Adrenal Cortex - physiology
Analysis of Variance
Animal Nutrition
Animals
Body Weight
Charadriiformes - physiology
Comparative Study
Corticosterone - blood
Energy Metabolism - physiology
Food Deprivation - physiology
Hypothalamo-Hypophyseal System - physiology
Nesting Behavior - physiology
Pituitary-Adrenal System - physiology
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Stress - metabolism
Thyroid Hormones - blood
Abstract
In several seabirds, nutritional state of a nest-bound chick is negatively correlated with the activity of its hypothalamus-pituitary-adrenal (HPA) axis. Increased corticosterone (cort) secretion has been shown to facilitate changes in behavior that allow hungry chicks to obtain more food from parents. However, if parents are not willing/able to buffer their young from temporary food shortages, increased cort secretion could be detrimental to undernourished chicks. In a system where parents are insensitive to chick demands, low benefits and high costs of activation of the HPA-axis in hungry chicks should lead to a disassociation of the nutritional state of the young and the activity of its HPA-axis. We tested this novel hypothesis for the tufted puffin (Fratercula cirrhata), a seabird with intermittent provisioning of a nest-bound semi-precocial chick. We examined the HPA-axis activity of captive chicks exposed to the following: (1) a short-term (24 h) food deprivation; and (2) an array of prolonged (3 weeks) restrictions in feeding regimens. We found that in response to a short-term food deprivation chicks decreased baseline levels of cort and thyroid hormones. In response to prolonged restrictions, food-limited chicks exhibited signs of nutritional deficit: they had lower body mass, endogenous lipid reserves, and thyroid hormone titers compared to chicks fed ad libitum. However, baseline and maximum acute stress-induced levels of cort were also lower in food-restricted chicks compared to those of chicks fed ad libitum. These results support a major prediction of the study hypothesis that puffin chicks suppress HPA-axis activity in response to short- and long-term nutritional deficits. This physiological adaptation may allow a chick to extend its development in the nest, while eluding detrimental effects of chronic cort elevation.
PubMed ID
15811363 View in PubMed
Less detail

Arctic ground squirrel resist peroxynitrite-mediated cell death in response to oxygen glucose deprivation.

https://arctichealth.org/en/permalink/ahliterature294918
Source
Free Radic Biol Med. 2017 12; 113:203-211
Publication Type
Journal Article
Research Support, N.I.H., Extramural
Research Support, U.S. Gov't, Non-P.H.S.
Date
12-2017
Author
Saurav Bhowmick
Kelly L Drew
Author Affiliation
Department of Chemistry and Biochemistry, University of Alaska Fairbanks, Fairbanks, AK, USA; Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK, USA.
Source
Free Radic Biol Med. 2017 12; 113:203-211
Date
12-2017
Language
English
Publication Type
Journal Article
Research Support, N.I.H., Extramural
Research Support, U.S. Gov't, Non-P.H.S.
Keywords
Animals
Brain Injuries - etiology - metabolism - physiopathology
Cell Death
Disease Models, Animal
Female
Food Deprivation
Glucose - metabolism
Hippocampus - metabolism - physiopathology
Hypoxia-Ischemia, Brain - metabolism - physiopathology
Male
Nitrosative Stress
Oxidative Stress
Oxygen - metabolism
Peroxynitrous Acid - toxicity
Rats
Rats, Sprague-Dawley
Reperfusion Injury - complications
Sciuridae
Abstract
Cerebral ischemia-reperfusion (I/R) injury initiates a cascade of events, generating nitric oxide (NO) and superoxide(O2•-) to form peroxynitrite (ONOO-), a potent oxidant. Arctic ground squirrels (AGS; Urocitellus parryii) show high tolerance to I/R injury. However, the underlying mechanism remains elusive. We hypothesize that tolerance to I/R modeled in an acute hippocampal slice preparation in AGS is modulated by reduced oxidative and nitrative stress. Hippocampal slices (400µm) from rat and AGS were subjected to oxygen glucose deprivation (OGD) using a novel microperfusion technique. Slices were exposed to NO, O2.- donors with and without OGD; pretreatment with inhibitors of NO, O2.- and ONOO- followed by OGD. Perfusates collected every 15min were analyzed for LDH release, a marker of cell death. 3-nitrotyrosine (3NT) and 4-hydroxynonenal (4HNE) were measured to assess oxidative and nitrative stress. Results show that NO/O2.- alone is not sufficient to cause ischemic-like cell death, but with OGD enhances cell death more in rat than in AGS. A NOS inhibitor, SOD mimetic and ONOO- inhibitor attenuates OGD injury in rat but has no effect in AGS. Rats also show a higher level of 3NT and 4HNE with OGD than AGS suggesting the greater level of injury in rat is via formation of ONOO-.
Notes
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PubMed ID
28962873 View in PubMed
Less detail

Aroclor 1254 exposure reduces disease resistance and innate immune responses in fasted Arctic charr.

https://arctichealth.org/en/permalink/ahliterature302920
Source
Environ Toxicol Chem. 2005 Jan;24(1):117-24.
Publication Type
Article
Date
2005
Author
Maule AG
Jørgensen EH
Vijayan MM
Killie JE
Source
Environ Toxicol Chem. 2005 Jan;24(1):117-24.
Date
2005
Language
English
Publication Type
Article
Keywords
Aeromonas salmonicida
Metabolism
toxicity
Immunology
Physiology
Chemistry
Drug effects
Animals
Chlorodiphenyl (54% Chlorine)
Food Deprivation
Gram-Negative Bacterial Infections
Immunity, Innate
Kidney
Lectins
Muramidase
Muscle, Skeletal
Salmonidae
Water Pollutants, Chemical
Abstract
To examine the immunological impacts of polychlorinated biphenyls (PCBs) in an environmentally relevant way, we orally contaminated Arctic charr (Salvelinus alpinus) with Aroclor 1254. After contamination, fish were either fed (0 and 100 mg Aroclor 1254 kg(-1) fish wt) or fasted (0, 1, 10, and 100 mg kg(-1)) to mimic cycles of feeding-fasting experienced by Arctic animals. After four months, PCB concentrations in muscle were the same in fasted and fed fish; however, PCBs in kidneys of fed fish were 33 to 50% of those in fasted fish. Arctic charr were exposed to Aeromonas salmonicida, the bacteria responsible for furunculosis, by cohabitation with infected conspecifics. Fasted fish had a significant trend toward lower survival with higher dose of PCBs--from 68% in controls to 48% in treatment involving 100 mg kg(-1). Independent of PCB contamination, fed fish had the lowest survival; we attribute this to stress associated with establishing and maintaining feeding hierarchies. A significant decrease in the activity of lysozyme was observed in skin mucus, as was hemagglutination ability of a putative rhamnose lectin in fasted, but not in fed, PCB-treated fish. These results demonstrate the immunosuppressive effects of PCBs on Arctic charr, and they illustrate the importance of considering environmentally relevant nutritional status in ecotoxicological studies.
PubMed ID
15683174 View in PubMed
Less detail

Caloric density affects food hoarding and intake by Siberian hamsters.

https://arctichealth.org/en/permalink/ahliterature61996
Source
Physiol Behav. 1996 Apr-May;59(4-5):897-903
Publication Type
Article
Author
A D Wood
T J Bartness
Author Affiliation
Department of Psychology, Georgia State University, Atlanta 30303, USA.
Source
Physiol Behav. 1996 Apr-May;59(4-5):897-903
Language
English
Publication Type
Article
Keywords
Animals
Body Weight - drug effects - physiology
Cricetinae
Diet
Dietary Fats - pharmacology
Eating - drug effects - physiology
Energy Intake - physiology
Energy Metabolism - physiology
Feeding Behavior - drug effects
Food Deprivation - physiology
Male
Research Support, U.S. Gov't, P.H.S.
Abstract
Siberian hamsters respond to food deprivation or restriction by increasing their food hoarding and do so proportionately to the degree of body mass (fat) loss. These data suggest that Siberian hamsters integrate their internally stored energy as body fat with their externally stored energy as hoarded food such that when internal energy stores are decreased, external stores are increased. The purpose of the present experiments was to test whether the caloric value of the food hoard is regulated. This was accomplished by challenging the hamsters with diets of varying caloric density and assessing whether their hoarded food is changed accordingly. Specifically, in Experiment 1 hamsters were switched from the control food pellets to a diet where the caloric density was increased by creating a high fat diet (HFD). In Experiment 2, the caloric density of the control diet was decreased by diluting it with cellulose such that 25% and 50% (kcal/wt) reduced calorie diets (RCDs) were created. HFD-fed hamsters decreased their food hoarding, increased their body mass, and decreased the grams of food eaten, but not enough to compensate exactly for the increased caloric density of the diet. When refed the control diet, food hoarding increased to pre-HFD levels as body mass and food intake decreased. RCD feeding resulted in caloric density-dependent effects on all measures. Food hoarding and intake (grams and calories) increased when hamsters were given the 25% RCD and did so to an even greater degree when given the 50% RCD. Thus, Siberian hamsters responded to increases or decreases in the caloric density of their food by attempting to regulate the number of calories hoarded and eaten; however, the adjustments in food hoarding: 1) were not precise, 2) were largely opposite of food intake, 3) tended to be inversely related to body mass and 4) were caloric density dependent.
PubMed ID
8778884 View in PubMed
Less detail

Caloric restriction decreases age-dependent accumulation of the glycoxidation products, N epsilon-(carboxymethyl)lysine and pentosidine, in rat skin collagen.

https://arctichealth.org/en/permalink/ahliterature62021
Source
J Gerontol A Biol Sci Med Sci. 1995 Nov;50(6):B337-41
Publication Type
Article
Date
Nov-1995
Author
W T Cefalu
A D Bell-Farrow
Z Q Wang
W E Sonntag
M X Fu
J W Baynes
S R Thorpe
Author Affiliation
Department of Internal Medicine, Bowman Gray School of Medicine, Winston-Salem, North Carolina, USA.
Source
J Gerontol A Biol Sci Med Sci. 1995 Nov;50(6):B337-41
Date
Nov-1995
Language
English
Publication Type
Article
Keywords
Aging - metabolism
Animals
Arginine - analogs & derivatives - metabolism
Blood Proteins - metabolism
Chromatography, High Pressure Liquid
Collagen - metabolism
Comparative Study
Energy Intake - physiology
Female
Food Deprivation
Glycosylation End Products, Advanced - metabolism
Lysine - analogs & derivatives - metabolism
Oxidation-Reduction
Rats
Rats, Inbred BN
Research Support, U.S. Gov't, P.H.S.
Skin - metabolism
Abstract
Nonenzymatic glycation of body proteins and subsequent advanced glycation reactions have been implicated in the aging process, while caloric restriction (CR) in rodents results in an increase in both mean and maximum life span. We have evaluated the effect of chronic (25 months) CR on glycation of blood proteins and accumulation of advanced glycation and oxidation (glycoxidation) products, N epsilon-(carboxymethyl)lysine (CML), and pentosidine, in skin collagen. Brown-Norway rats, fed ad libitum (AL) from birth, were divided into two equal groups at 4 months of age and placed on AL or CR diets (CR = 60% of AL diet). Cohorts of animals were sacrificed at 7, 13, and 25 months after the initiation of CR. At necropsy glycated hemoglobin was measured by affinity HPLC and glycated plasma protein by the fructosamine assay; extracts of skin collagen were analyzed by gas chromatography-mass spectrometry for CML and by reversed-phase HPLC for pentosidine. Glycation of hemoglobin, plasma proteins, and skin collagen was decreased significantly (18-33%) by CR. Concentrations of CML and pentosidine increased significantly with age in skin collagen in both AL and CR animals; however, CR significantly reduced levels of CML (25%), pentosidine (50%), and fluorescence (15%) in collagen in the oldest rats. We conclude that CR reduces the extent of glycation of blood and tissue proteins and the age-related accumulation of glycoxidation products in skin collagen.
PubMed ID
7583789 View in PubMed
Less detail

Daylength and body mass affect diet self-selection by Siberian hamsters.

https://arctichealth.org/en/permalink/ahliterature61989
Source
Physiol Behav. 1996 Jun;59(6):1039-50
Publication Type
Article
Date
Jun-1996
Author
J B Fine
T J Bartness
Author Affiliation
Department of Psychology, Georgia State University, Atlanta 30303, USA.
Source
Physiol Behav. 1996 Jun;59(6):1039-50
Date
Jun-1996
Language
English
Publication Type
Article
Keywords
Adipose Tissue - anatomy & histology - physiology
Animals
Body Weight - physiology
Cricetinae
Diet
Dietary Carbohydrates - administration & dosage
Dietary Fats - administration & dosage
Dietary Proteins - administration & dosage
Energy Intake - physiology
Food Deprivation - physiology
Food Preferences - physiology
Male
Organ Size - physiology
Phodopus
Photoperiod
Research Support, U.S. Gov't, P.H.S.
Seasons
Time Factors
Abstract
Siberian hamsters exhibit a decrease in peak body mass/fat and caloric intake when they are exposed to short winter-like days (SDs) compared with hamsters exposed to long summer-like days (LDs). We hypothesize that the photoperiod may directly or indirectly mediate alterations in gustatory processing that may account for shifts in the preferences for specific food types and/or macronutrients. Two experiments lasting 14 days each were conducted to: 1) identify photoperiod-related differences in diet selection, and; 2) determine whether these differences were a primary effect of SD exposure or a secondary effect due to SD-induced decreases in body fat/mass. In Experiment 1, two groups of hamsters were exposed to either LDs or SDs and given access to three complex food types [sunflower seeds (SF); rabbit chow (RC); millet seeds (M)]. In addition to their photoperiod-induced decreased body and fat pad mass, and caloric intake, SD-housed hamsters exhibited significant differences in their patterns of diet selection and relative amounts of fat, carbohydrate (COH), and protein eaten compared with LD-housed hamsters. By the end of the experiment, SD-housed hamsters selected a diet higher in COH and protein and lower in fat than that selected by LD-housed hamsters. Because SD-housed hamsters decrease their body mass/fat, this may reflect an adaptive strategy to maintain a leaner body mass. A second experiment was conducted to test whether the diet selection pattern of SD-housed hamsters was due to the SD-induced decrease in body mass/fat. LD-housed hamsters were allowed to feed ad lib (AL group), or were food restricted (FR group) to simulate a SD-induced decrease in body mass. Both groups were then released into the diet self-selection paradigm. FR hamsters reversed their food restriction-induced decrease in body mass and showed concurrent alterations in diet self-selection patterns that were distinct from the SD-induced patterns seen in Experiment 1. Specifically, they showed a persistent hyperphagia and selected a larger proportion of their total calories as M (high COH) and less as SF (high fat) than did AL hamsters during their return to LD body mass levels. However, once LD body mass levels were achieved, they increased their SF intake, and thus fat consumption. Despite these dynamic daily changes, the average selection patterns of both the diet types and macronutrients were not different by the end of the experiment. Therefore, it appears that the SD-induced changes in the selection of food sources (and ultimately, the macronutrient composition of the diet) cannot be solely attributable to the SD-induced decreases in body mass.
PubMed ID
8737891 View in PubMed
Less detail

Diet self-selection and food hoarding after food deprivation by Siberian hamsters.

https://arctichealth.org/en/permalink/ahliterature61823
Source
Physiol Behav. 1999 Dec 1-15;68(1-2):187-94
Publication Type
Article
Author
D E Day
E M Mintz
T J Bartness
Author Affiliation
Department of Biology, Georgia State University, Atlanta 30303, USA.
Source
Physiol Behav. 1999 Dec 1-15;68(1-2):187-94
Language
English
Publication Type
Article
Keywords
Animals
Body Composition
Body Weight
Cricetinae
Energy intake
Female
Food Deprivation
Food Preferences - psychology
Motivation
Phodopus - psychology
Rabbits
Research Support, U.S. Gov't, Non-P.H.S.
Research Support, U.S. Gov't, P.H.S.
Stereotyped Behavior
Abstract
Siberian hamsters (Phodopus sungorus) increase food hoarding, but not food intake, after a fast. Because the physiological mechanisms underlying these changes in food hoarding are virtually unknown, we sought insight into these mechanisms by allowing hamsters to self-select their diet from food sources varying in macronutrient composition and caloric density ("dietary wisdom"). Therefore, the effects of food deprivation length on diet self-selection were tested in adult female hamsters after adaptation to three composite diets: sunflower seeds (SS), pellet chow (PC), and rabbit chow (RC). One group initially was fasted for 32 h, the other for 56 h, and then each was refed. The remaining nonexperienced fast was instated after prefast body mass, food intake, and hoarding were recovered. Food hoarding, but not food intake, was increased regardless of fast length or sequence; moreover, the largest increase in food hoarding was on the first day of refeeding and was primarily reflected as increased SS hoarding. When the longer fast occurred first body mass loss was greater and the increased food hoard size was maintained for more days than when the longer fast came second. The order of food intake and hoarding preferences was not changed after a fast (SS > PC > RC), but the degree of food hoarding preference for SS was exaggerated. Collectively, these results support the notion that food hoarding increases with decreases in lipid stores, and show that when internal lipid stores are decreased, external lipid stores are preferentially increased.
PubMed ID
10627080 View in PubMed
Less detail

Disentangling effects of growth and nutritional status on seabird stable isotope ratios.

https://arctichealth.org/en/permalink/ahliterature91430
Source
Oecologia. 2009 Feb;159(1):41-8
Publication Type
Article
Date
Feb-2009
Author
Sears Justine
Hatch Scott A
O'Brien Diane M
Author Affiliation
Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA. ftjss1@uaf.edu
Source
Oecologia. 2009 Feb;159(1):41-8
Date
Feb-2009
Language
English
Publication Type
Article
Keywords
Animal Nutritional Physiological Phenomena
Animals
Carbon - chemistry - metabolism
Carbon Isotopes - chemistry - metabolism
Charadriiformes - growth & development - physiology
Erythrocytes - chemistry
Feathers - chemistry
Food Deprivation
Nitrogen - chemistry - metabolism
Nitrogen Isotopes - chemistry - metabolism
Nutritional Status - physiology
Abstract
A growing number of studies suggest that an individual's physiology affects its carbon and nitrogen stable isotope signatures, obscuring a signal often assumed to be only a reflection of diet and foraging location. We examined effects of growth and moderate food restriction on red blood cell (RBC) and feather delta(15)N and delta(13)C in rhinoceros auklet chicks (Cerorhinca monocerata), a piscivorous seabird. Chicks were reared in captivity and fed either control (75 g/day; n = 7) or ~40% restricted (40 g/day; n = 6) amounts of high quality forage fish. We quantified effects of growth on isotopic fractionation by comparing delta(15)N and delta(13)C in control chicks to those of captive, non-growing subadult auklets (n = 11) fed the same diet. To estimate natural levels of isotopic variation, we also collected blood from a random sample of free-living rhinoceros auklet adults and chicks in the Gulf of Alaska (n = 15 for each), as well as adult feather samples (n = 13). In the captive experiment, moderate food restriction caused significant depletion in delta(15)N of both RBCs and feathers in treatment chicks compared to control chicks. Growth also induced depletion in RBC delta(15)N, with chicks exhibiting lower delta(15)N when they were growing the fastest. As growth slowed, delta(15)N increased, resulting in an overall pattern of enrichment over the course of the nestling period. Combined effects of growth and restriction depleted delta(15)N in chick RBCs by 0.92 per thousand. We propose that increased nitrogen-use efficiency is responsible for (15)N depletion in both growing and food-restricted chicks. delta(15)N values in RBCs of free-ranging auklets fell within a range of only 1.03 per thousand, while feather delta(15)N varied widely. Together, our captive and field results suggest that both growth and moderate food restriction can affect stable isotope ratios in an ecologically meaningful way in RBCs although not feathers due to greater natural variability in this tissue.
PubMed ID
18975007 View in PubMed
Less detail

Dispositional optimism and self-assessed situation awareness in a Norwegian military training exercise.

https://arctichealth.org/en/permalink/ahliterature49589
Source
Percept Mot Skills. 2005 Jun;100(3 Pt 1):649-58
Publication Type
Article
Date
Jun-2005
Author
Jarle Eid
Michael D Matthews
Nils Tore Meland
Bjørn Helge Johnsen
Author Affiliation
University of Bergen, Norway.
Source
Percept Mot Skills. 2005 Jun;100(3 Pt 1):649-58
Date
Jun-2005
Language
English
Publication Type
Article
Keywords
Adaptation, Psychological
Adult
Attitude
Awareness
Comparative Study
Decision Making
Female
Food Deprivation
Humans
Life Change Events
Male
Military Personnel - education - psychology
Norway
Personality
Personality Inventory
Research Support, U.S. Gov't, Non-P.H.S.
Sleep Deprivation
Stress - psychology
Stress, Psychological - psychology
Task Performance and Analysis
Abstract
The current study examined the relationship between dispositional optimism and situation awareness. A sample of 77 Royal Norwegian Naval Academy and 57 Royal Norwegian Army Academy cadets were administered the Life Orientation Test prior to participating in a field-training exercise involving a series of challenging missions. Following an infantry mission component of the exercise, situation awareness was measured using the Mission Awareness Rating Scale (MARS), a self-assessment tool. The analysis indicated that dispositional optimism correlated negatively with situation awareness under these conditions. The role of intrapersonal variables in mediating situation awareness and decision-making in stressful situations is discussed.
PubMed ID
16060424 View in PubMed
Less detail

Ducklings exhibit substantial energy-saving mechanisms as a response to short-term food shortage.

https://arctichealth.org/en/permalink/ahliterature57235
Source
Physiol Biochem Zool. 2005 Jan-Feb;78(1):90-104
Publication Type
Article
Author
Borge Moe
Einar Stolevik
Claus Bech
Author Affiliation
Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway. borge.moe@bio.ntnu.no
Source
Physiol Biochem Zool. 2005 Jan-Feb;78(1):90-104
Language
English
Publication Type
Article
Keywords
Analysis of Variance
Animals
Basal Metabolism
Body Composition
Body Constitution - physiology
Body Temperature Regulation - physiology
Body Weight
Body Weights and Measures
Comparative Study
Ducks - growth & development - physiology
Energy Metabolism - physiology
Food Deprivation - physiology
Linear Models
Norway
Oxygen Consumption - physiology
Research Support, Non-U.S. Gov't
Abstract
We investigated whether Pekin ducklings (Anas platyrhyncos domesticus) exhibited any energy-saving mechanisms that could lessen the detrimental effects of reduced food intake during early development. Further, we evaluated the role of body compositional changes behind such potential mechanisms and the consequences on thermoregulatory capacity. The ducklings exhibited substantial energy-saving mechanisms as a response to diet restriction. After 5 d of diet restriction, the resting metabolic rate (RMR) of 10- and 20-d-old ducklings was 16.4% and 32.1% lower, respectively, than predicted from body mass compared with ad lib. fed ducklings (controls). These reductions in RMR could have been adaptive responses in anticipation of a lasting food shortage, or they could have been consequences of the restricted diet and the lack of essential nutrients. We argue that the responses were adaptive. The low RMRs were not a consequence of depleted fuel stores because the diet-restricted ducklings exhibited substantial amounts of stored lipids at the end of the diet-restriction periods. Hypothermia accounted for approximately 50% of the reduction in RMR in the 10-d-old diet-restricted ducklings, but hypothermia did not occur in the 20-d-old diet-restricted ducklings. Diet restriction resulted in a reduced liver and intestine size and an unchanged size of the leg muscles and heart, while the length of the skull increased (compared with controls of a given body mass). However, changes in body composition were only minor predictors of the observed changes in RMR. Peak metabolic rate (PMR) was approximately 10% lower in the diet-restricted ducklings compared with the controls. We have interpreted the lower PMR as a consequence of the reductions in RMR rather than as a consequence of a decreased function of the thermoregulatory effector mechanisms.
PubMed ID
15702467 View in PubMed
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