scholarly journals The oxygen capacity of the blood after haemorrhage

1910 ◽  
Vol 39 (6) ◽  
pp. 453-460 ◽  
Author(s):  
C. Gordon Douglas
Keyword(s):  
Fuel ◽  
2021 ◽  
Vol 303 ◽  
pp. 121286
Author(s):  
Tao Wang ◽  
Yunfei Gao ◽  
Yongzhuo Liu ◽  
Minghang Song ◽  
Jingjing Liu ◽  
...  

2018 ◽  
pp. 151-178
Author(s):  
Richard R. Strathmann

Modes of development of marine crustaceans and other marine invertebrates include presence or absence of a larval stage, of larval feeding, and of maternal protection of offspring. These different developmental modes impose different compromises (trade-offs) between the number of offspring and their size or the extent of maternal protection. Crustaceans differ from many marine animals in not shedding eggs prior to fertilization, which eliminates the complication of selection on size of eggs as a target for sperm. Features shared with marine invertebrates of several phyla include rare and ancient origins of feeding larvae, irreversible losses of a feeding larval stage, a constraint on brooding imposed by embryos’ need for oxygen, and possible benefits from slower development of protected embryos. Crustaceans differ, however, in having a diverse exoskeletal tool kit that has provided unusual capabilities. Nauplii and zoeae are diverse in form, behavior, and habitat, despite each being nominally one type of larva. Nauplii, as feeding larvae, have adapted to both the benthos and plankton. Settling stages (cyprids and decapodids) with enhanced speed have evolved twice. Some very large adults can supply their large broods with oxygen. Capacity for defense of offspring and home has led a few times to eusociality. The need to molt to grow and change form imposes episodic risk and growth and, in some cases, links evolution of egg size and size at metamorphosis. Crustaceans’ diverse life histories enable comparisons with broad implications for marine invertebrates: opportunity for dispersal is similar for larvae and adults of some crustaceans, demonstrating that marine larvae need not be adaptations for dispersal; development from very small eggs is enabled by less equipment needed for first larval feeding and also by postlarval stages being parasites; eggs shed into the water suffer greater mortality than planktonic larvae or brooded eggs, yet some planktonic crustaceans depend on benthic resting eggs for persistence of populations; larvae escape predation in diverse ways, and bigger larvae are not consistently safer; predation near the seafloor makes settlement a risky stage. Parallels with other taxa are numerous, but the crustacean exoskeletal tool kit has conferred unusual evolutionary opportunities and constraints. Even among marine crustaceans, however, evolutionary options for life histories differ among clades because of rare evolutionary origins of traits of larvae and mothers and biased evolutionary transitions in those traits.


1960 ◽  
Vol 199 (1) ◽  
pp. 179-182 ◽  
Author(s):  
Abraham Guz ◽  
George S. Kurland ◽  
A. Stone Freedberg

Coronary flow, heart rate, myocardial oxygen consumption and Walton strain gauge tension were determined in the isolated rabbit heart perfused with hemoglobin solutions of varying oxygen content. Perfusion was carried out under constant pressure and with the hemoglobin solution in equilibrium with 3% CO2 and 97% air under atmospheric tension. Oxygen content was varied from 2 to 18 vol. % by diluting hemoglobin with Ringer-Locke solution. Change from a higher to lower oxyhemoglobin concentration resulted in increased coronary flow; the reserve led to decreased flow. Heart rate, myocardial tension and oxygen consumption were constant at oxygen capacity above 2 vol. %.


1965 ◽  
Vol 43 (3) ◽  
pp. 433-438 ◽  
Author(s):  
R. F. Burton

The copper content of the haemocyanin of Helix pomatia is about 0.25%.When the concentration of haemocyanin in the blood exceeds a certain value, the increased oxygen capacity of the blood is offset by its viscosity. This critical concentration exceeds 100 g per kilogram of water and is thus above the range of concentrations found in H. pomatia. The amount of haemocyanin in the blood seems not to be limited by solubility, but, whilst other factors may be involved, it is likely that the amount synthesized by a snail is sometimes limited by the availability of copper or other nutrients.


1967 ◽  
Vol 24 (11) ◽  
pp. 2267-2281 ◽  
Author(s):  
Mary Anne DeWilde ◽  
A. H. Houston

The blood oxygen capacity of the rainbow trout has been investigated as a function of thermal acclimation in terms of erythrocyte abundance, packed cell volume, hemoglobin concentrations, and mean erythrocytic volume and hemoglobin content. Fish at the lower acclimation temperatures employed (3, 7 C) were characterized by relatively low erythrocyte counts, hematocrits, and hemoglobin levels. Mean erythrocyte volumes tended to be relatively high, whereas mean erythrocytic hemoglobin content was somewhat below that typical of the higher temperature groups. In general, animals held at intermediate temperatures (11, 14, 17 C) showed significant increases in oxygen-carrying capacity by comparison with cold-acclimated fish. Finally trout at 21 C typically had larger numbers of somewhat smaller red cells, more hemoglobin, and higher levels of hemoglobin per erythrocyte than either the low- or intermediate-temperature fish. Significant differences were observed between summer and fall–winter series of trout, particularly with respect to hemoglobin levels. The results are discussed in relation to the general problem of respiratory thermoadaptation.


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