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111.
Rodney A. Bray 《Systematic parasitology》1990,15(1):1-21
The genus Parahemiurus Vaz & Pereira, 1930 (syn.: Daniella Sahai & Srivastava, 1977) is defined, its major morphological characters discussed and a key to species given. The species
P. merus (Linton, 1910) (syns: P. parahemiurus Vaz & Pereira, 1930, P. sardiniae Yamaguti, 1934, P. seriolae Yamaguti, 1934, P. platichthyi Lloyd, 1938, P. atherinae Yamaguti, 1938, P. harengulae Yamaguti, 1938, P. noblei King, 1962) and P. anchoviae Pereira & Vaz, 1930 are described. Other species recognized are P. clupeae Yamaguti, 1953, P. [originally Daniella] madrasensis (Sahai & Srivastava, 1977) n. comb. (syns: P. dussumieriai Hafeezullah, 1981, P. indicus Ahmad, 1981), P. ecuadori Manter, 1940, P. engraulisi Gupta & Jahan, 1977 (syns: P. cameroni Gupta & Ahmad, 1977, P. puriensis Ahmad, 1981, P. simhai Gupta & Gupta, 1978, P. tricanthusi Gupta & Puri, 1984) and P. yanamense Hafeezullah, 1980. Forms considered species inquirendae are P. arripidis Lebedev, 1971, P. clupeae of King (1964), P. dogieli Skrjabin & Guschanskaya, 1953, P. pseudosciaenae Shen, 1985 and P. trachichthodi Lebedev, 1968. Host and locality information is given in detail for all species. The complete life-cycle is not known, but
metacercariae are reported in chaetognaths and teleosts. The definitive hosts of Parahemiurus spp. most frequently reported belong in the families Clupeidae and Carangidae and the genus is most commonly reported in
temperate and subtropical waters. 相似文献
112.
113.
S. F. Perry 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1990,159(6):761-769
Summary The respiratory surface area (SAR) per kilogram body mass (MB), the harmonic mean thickness of the air-blood barrier (htR) in the gas exchange tissue, and the anatomical diffusion factor (ADF=SAR/htR per MB) were calculated for four juvenile Nile crocodiles. The ADF of three small specimens (mean MB=3.59 kg) was 625 cm2·m–1·kg–1. The values varied considerably among individuals and were similar to that of a 5.68-kg specimen (593 cm2·m–1·kg–1). Only 9% of the ADF is located in the anterior third of the lung, which because of its conical shape makes up only 14 percent of the total lung volume. Particularly in the middle third of the lung, the proximal region near the intrapulmonary bronchus displays a greater ratio of respiratory/non-respiratory surface areas than do more distally located sampling sites. The htR is also significantly smaller proximally than distally. The cumulative ADF per unit MB is greater than that previously reported for this species on the basis of overall estimates of SAR and htR, but is still less than that of lizards and testudinids. The disposition of ADF between distal air storage region and the intrapulmonary bronchus is consistent with a bidirectional cross-current gas exchange model.Abbreviations
ADF
anatomical diffusion factor
- %AR
percent of SA included in the effective respiratory zone
-
M
B
body mass
-
NVP
non-ventilatory period
- %P
percent of total lung volume containing parenchyma
-
S
A
total surface area of intrapulmonary septa
-
S
ANR
that portion ofS
A
lying out the effective respiratory zone
-
S
V
surface-to-volume ratio in the parenchyma
- htR
harmonic mean thickness of the air-blood tissue barrier within the respiratory zone
-
V
P
parenchymal volume
-
VP
ventilatory period 相似文献
114.
D. A. Hyde S. F. Perry 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1990,159(6):687-693
Summary American eels (Anguilla rostrata) were exposed to acute (30 min) external hypercapnia (1% CO2 or 5% CO2 in air) in order to assess the involvement of circulating catecholamines in regulating red blood cell (RBC) pH and oxygen content during whole blood acidosis. Plasma adrenaline levels increased approximately 5-fold during severe hypercapnia yet absolute levels remained below 1.0 nM; plasma noradrenaline levels were unchanged. Both RBC pH and oxygen bound to haemoglobin ([O2]/[Hb]) conformed to in vitro relationships with whole blood pH (pHe) indicating absence of regulation during hypercapnia in vivo. Pre-treatment of eels with - or -adrenoceptor antagonists, phentolamine or propranolol was without effect on RBC pH or [O2]/[Hb] during hypercapnia. Further, intra-arterial injection of adrenaline (final plasma concentration=134 nM) or noradrenaline (final plasma concentration = 34 nM) into hypercapnic eels 5 min prior to blood sampling did not modify any measured blood variable RBC nucleoside triphosphate (NTP) levels, RBC pH and [O2]/[Hb]. In vitro, the application of adrenaline or noradrenaline to eel RBC's during graded normoxic hypercapnia or hypoxic hypercapnia (noradrenaline only) did not affect RBC pH significantly. RBC NTP levels were depressed by noradrenaline in vitro but only during hypoxic hypercapnia.The results demonstrate adrenergic insensitivity of eel RBC's in vivo even under conditions (acidosis, hypoxemia) known to enhance catecholamine-mediated RBC responses in other species. We conclude that the American eel has no capacity to regulate RBC pH during hypercapnia and consequently [O2]/[Hb] is reduced in accordance with the in vitro Root effect. 相似文献
115.
Grant St. Julian Rodney J. Bothast Larry H. Krull 《Journal of industrial microbiology & biotechnology》1990,5(6):391-394
Summary By succesive recycling of the thin stillage in mashing and fermenting fresh corn, the glycerol content in each fermentation increased by about 0.4% and accumulated to a high of 2.1% in the beer of the fifth recycle. Glycerol concentration declined after the fifth recycle. The original fermentation contained 0.8% glycerol.Presented in part at the Society for Industrial Microbiology Annual Meeting, August 7–12, 1988, Chicago, IL.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned. 相似文献
116.
John Curry Rebecca Huss-Ashmore Brian Perry Adrian Mukhebi 《Human ecology: an interdisciplinary journal》1996,24(2):161-189
As livestock disease control programs in Africa begin to rely more upon para-professionals and livestock producers as deliverers of animal health care services, understanding the role different household members play in providing animal health care becomes increasingly important. This paper presents a framework for the analysis of gender aspects of livestock disease control based on a similar framework developed by Feldstein and Poats (1989). The utility of this framework is illustrated using household-level data collected from a district in central Kenya. Adult women and elderly men in the sample have primary responsibility for livestock care, and are therefore well placed to diagnose illness. Dipping and spraying of animals to prevent tick-borne and other diseases is the primary responsibility of adult males. Decisions regarding use of milk from the morning milking are more likely to be made by adult men. It is morning milk that is most often sold. Adult women, however, make decisions about use of evening milk, which is most often kept for household consumption. Knowledge of livestock diseases did not appear to vary significantly by gender, although some elderly men did possess extensive knowledge of indigenous disease categories and traditional remedies. The importance of recognizing gender issues in planning and implementing livestock disease control programs is discussed. 相似文献
117.
Summary Forty-eight yeast strains belonging to the genera Candida, Debaryomyces, Kluyveromyces and Pichia (obtained from the ARS Culture Collection, Peoria, IL) were screened for production of extracellular glucose tolerant and thermophilic -glucosidase activity using p-nitrophenyl--D-glucoside as substrate. Enzymes from 15 yeast strains showed very high glucose tolerance (<50 % inhibition at 30 %, w/v glucose). The optimal temperatures and pH for these -glucosidase activities varied from 30 to 65°C and pH 4.5 to 6.5. The -glucosidases from all these yeast strains hydrolyzed cellobiose.Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable. 相似文献
118.
The genusLepidauchen is discussed and defined. It is removed from the family Lepocreadiidae and placed in the family Acanthocolpidae based mainly on its possession of a uterine seminal receptacle. The type, and only valid species,L. stenostoma, is redescribed using material fromLabrus merula from Corsica. Material fromCoris julis andSymphodus tinca from the western Mediterranean off Marseille,L. merula from the western Mediterranean off Valencia,Diplodus annularis andLithognathus mormyrus from the Adriatic Sea off Montenegro, andArchosargus unimaculatus from Venezuela was also examined. Other nominal species are discussed, but none are considered valid within this genus. 相似文献
119.
Modulation of catecholamine storage and release by the pituitary-interrenal axis in the rainbow trout,Oncorhynchus mykiss 总被引:2,自引:0,他引:2
S. G. Reid M. M. Vijayan S. F. Perry 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1996,165(8):665-676
This study examined the effects of pituitary-interrenal hormones on catecholamine storage and release in the rainbow trout Oncorhynchus mykiss. An extract of trout pituitary elicited the release of adrenaline, but not noradrenaline, using an in situ perfusion preparation. A variety of doses of adrenocorticotropic hormone (2–2000 mU) caused the release of both catecholamines in situ which was unaffected by pre-treatment with the ganglion blocker, hexamethonium, or the serotonergic receptor antagonist, methysergide, but was abolished in calcium-free media. Intra-arterial injections of adrenocorticotrophic hormone in vivo caused an elevation of plasma adrenaline but not noradrenaline levels. Injections of cortisol in situ did not elicit catecholamine release. Trout given an intraperitoneal implant of cortisol (50 mg·kg-1 body weight) had significantly higher plasma cortisol concentrations when compared to controls after 7 days of implantation. Increases in the levels of stored catecholamines were observed in various regions of the kidney and posterior cardinal vein following 3 and 7 days of cortisol treatment. The ability of the chromaffin cells to release catecholamines in response to cholinergic stimulation was assessed in situ after 7 days of treatment. Basal (non-stimulated) adrenaline outflowing perfusate levels were greater in the cortisol-treated fish. Cortisol treatment increased the responsiveness of the catecholamine release process to low doses of the cholinoceptor agonist carbachol. Three or 7 days of cortisol treatment did not alter the in vitro activity of the enzyme phenylethanolamine-N-methyl-transferase. The results of this study demonstrate that interactions within the pituitary-adrenal axis can influence both catecholamine storage and release in the rainbow trout.Abbreviations
ACTH
adrenocorticotropic hormone
-
AK
anterior third of the kidney
-
APCV
anterior third of the PCV
-
HPLC
high performance liquid chromatography
-
MK
middle third of the kidney
-
M1
maximum value
-
MPCV
middle third of the PCV
-
MS222
ethyl-aminobenzoate
-
P1
pre value
-
PCA
perchloric acid
-
PCV
posterior cardinal vein
-
PK
posterior third of the kidney
-
PNMT
phenylethanolamine-N-methyltransferase
-
PPCV
posterior third of the PCV
-
rbc
red blood cells
-
SEM
standard error of the mean
-
TK
total kidney (i.e. the sum of the AK, MK, and PK)
-
TPCV
total PCV (i.e. the sum of the APCV, MPCV and PPCV) 相似文献
120.
Tama Hasson Joseph F. Skowron Debra J. Gilbert Karen B. Avraham William L. Perry William M. Bement Blake L. Anderson Elliott H. Sherr Zheng-Yi Chen Lloyd A. Greene David C. Ward David P. Corey Mark S. Mooseker Neal G. Copeland Nancy A. Jenkins 《Genomics》1996,36(3):431
Myosins are molecular motors that move along filamentous actin. Seven classes of myosin are expressed in vertebrates: conventional myosin, or myosin-II, as well as the 6 unconventional myosin classes -I, -V, -VI, -VII, -IX, and -X. We have mapped in mouse 22 probes encompassing all known unconventional myosins and, as a result, have identified 16 potential unconventional myosin genes. These genes include 7 myosins-I, 2 myosins-V, 1 myosin-VI, 3 myosins-VII, 2 myosins-IX, and 1 myosin-X. The map location of 5 of these genes was identified in human chromosomes by fluorescencein situhybridization. 相似文献