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241.
A simple technique for artificial insemination in hares was performed and used routinely in mass breeding of hares in captivity. Sperm was collected directly from the epididymides of males. Ovulation was induced by intravenous injection of human chorionic gonadotropin. Female hares were successfully inseminated throughout the year. Pregnancy occurred in 70% of inseminated females; the range in litter size was 1--3 offspring with a mean of 1.4. It was concluded that artificial insemination greatly simplified the breeding of hares in captivity. 相似文献
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A Bar-Ilan J Marder S Samueloff 《Comparative biochemistry and physiology. A, Comparative physiology》1985,81(3):571-576
Arterial blood acid-base status of unanesthetized sand rats (Psammomys obesus) were studied under normocapnic and hypercapnic conditions, and compared to those obtained for the albino rat (Rattus norvegicus). The average control blood pH: 7.396 +/- 0.034; PaCO2: 30.5 +/- 2.9 mmHg; HCO-3: 18.8 +/- 2.5 mM/l; and HCO-3 std: 20.9 +/- 2.1 (N = 15) obtained here for the sand rat are in the lower range of values found in other mammals and indicate a status of partially compensated metabolic acidosis. The blood buffer values of the sand rat, delta log PCO2/delta pH = -2.32 +/- 0.35 (N = 25) are significantly higher than those found here for the rat, delta log PCO2/delta pH = -1.51 +/- 0.10 (N = 39), and those reported for other mammals. This high blood buffer value may be related to the natural high mineral diet of the sand rat. The in vivo (whole body) buffer value delta log PaCO2/delta pH = -1.41 and -1.65 for the sand rat and the rat found here are higher than those reported for the man and dog and may represent a physiological adaptation to the hypercapnic conditions prevailing in underground burrows. 相似文献
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James F. Ponder Akanksha K. Menon Raghunath R. Dasari Sandra L. Pittelli Karl J. Thorley Shannon K. Yee Seth R. Marder John R. Reynolds 《Liver Transplantation》2019,9(24)
Conjugated polymers with high electrical conductivities are attractive for applications in capacitors, biosensors, organic thermoelectrics, and transparent electrodes. Here, a series of solution processable dioxythiophene copolymers based on 3,4‐propylenedioxythiophene (ProDOT) and 3,4‐ethylenedioxythiophene (EDOT) is investigated as thermoelectric and transparent electrode materials. Through structural manipulation of the polymer repeat unit, the conductivity of the polymers upon oxidative solution doping is tuned from 1 × 10?3 to 3 S cm?1, with a polymer consisting of a solubilizing alkylated ProDOT unit and an electron‐rich biEDOT unit (referred to as PE2) showing the highest electrical conductivity. Optimization of the film casting method and screening of dopants result in AgPF6‐doped PE2 achieving a high electrical conductivity of over 250 S cm?1 and a thermoelectric power factor of 7 μW m?1 K?2. Oxidized spray cast films of PE2 are also assessed as a transparent electrode material for use with another electrochromic polymer. This bilayer shows reversible electrochemical switching from a colored charge‐neutral state to a highly transmissive color‐neutral, oxidized state. These results demonstrate that dioxythiophene‐based copolymers are a promising class of materials, with ProDOT–biEDOT serving as a soluble analog to the well‐studied PEDOT as a p‐type thermoelectric and electrode material. 相似文献
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Small invertebrate nervous systems allow one to ask a series of questions concerning the functional roles of cotransmitters.
This review outlines some of the implications of cotransmission for target selectivity in complex neuropils. We suggest the
possibility that a unique constellation of cotransmitters in individual identified modulatory neurons allows a specificity
of action even when peptides may act over an extended distance, and when individual modulatory substances may be released
from several modulatory neurons. 相似文献