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991.
A molecular view of vertebrate retinal development 总被引:4,自引:0,他引:4
Colin J. Barnstable 《Molecular neurobiology》1987,1(1-2):9-46
992.
Observations are reported on seasonal changes in the age structure of populations of nematodes of the family Trichonematidae recovered at regular intervals from the lumens of the large intestines of horses slaughtered in S.W. England. The results show that changes in the size of parasitic populations of Trichonema nassatum follow seasonal variations in the rate of infection, more individuals maturing during summer/autumn than during winter/spring because of proportional differences in the numbers of infective larvae ingested from the pasture. In contrast, larvae of T. longibursatum, T. catinatum and T. goldi ingested by grazing horses during summer accumulate in the gut wall rather than promptly returning to the lumen and developing to maturity. Their development is apparently inhibited until the following spring when 4th-stage larvae emerge en masse and quickly reach the adult stage. The relationship between fluctuations in the size of the adult populations of the 4 species studied and the characteristic seasonal variations in horse faecal egg counts is discussed. 相似文献
993.
Summary The frequencies of the pseudocholinesterase alleles E1
u, E1
a and E1
f have been determined in a random sample of Australian residents. The frequency of E1
a is the highest yet reported in a large caucasian sample. The considerable variation in E1
f frequencies in previously reported samples is discussed in terms of possible sources of error in fluoride number determinations.Enzyme activity was found to increase with age in adulthood and was higher in males than in females. It was also positively correlated with dibucaine number in type U subjects. These observations are in conflict with those reported in previous investigations.This work was supported by grants from the National Health and Medical Research Council of Australia and the Australian Tobacco Research Foundation. 相似文献
994.
We show that, in 1862, Richard Burton collected the type specimen of Pan troglodytes vellerosus not on Mount Cameroon, as has been generally assumed, but in Gabon. Therefore, P. t. vellerosus is not the correct name for the chimpanzee population of western Cameroon and southern Nigeria, if that population is taxonomically
distinct. As First Reviser, we choose the name Pan troglodytes ellioti for this population of chimpanzees, based on Anthropopithecus
ellioti named by Matschie [Matschie P (1914) Neue Affen aus Mittelafrika. Sitzungsber Ges Naturforsch Freunde Berlin 1914:323–342] from a specimen in the Humboldt Museum,
Berlin, collected in Bascho (=Basho), Cameroon, and given to the museum in 1905. 相似文献
995.
996.
A 35 year old female patient with acute lymphocytic leukemia developed fusariosis in which dissemination appeared to be limited to cutaneous and vascular invasion. The first evidence of fungemia occurred nearly seven months after initial hospitalization. The fungus was identified asFusarium sp. and was considered a contaminant. Two weeks later blood cultures were again positive forFusarium sp. and the patient was placed on amphotericin B and 5-fluorocytosine therapy. The following day developing lesions were noted on her forearms and face; lesions ultimately spread to her trunk, abdomen, and lower extremities. Skin lesion biopsy sections revealed abundant septate and branching hyphae throughout the dermis and within capillaries. Twenty-six days after the initial isolation the patient died. Post-mortem blood cultures gave rise to the same fungus, which was identified asFusarium monoliforme. Postmortem cultures and stains of spleen, liver, lung, and brain specimens were all negative for fungi. The primary source and portal of entry of the organism remained undetermined. 相似文献
997.
998.
999.
1000.
Colin F. Fletcher Neal G. Copeland Nancy A. Jenkins 《Journal of bioenergetics and biomembranes》1998,30(4):387-398
Molecular cloning of calcium channel subunit genes has identified an unexpectedly large number of genes and splicing variants, and a central problem of calcium channel biology is to now understand the functional significance of this genetic complexity. While electrophyisological, pharmacological, and molecular cloning techniques are providing one level of understanding, a complete understanding will require many additional kinds of studies, including genetic studies done in intact animals. In this regard, an intriguing variety of episodic diseases have recently been identified that result from defects in calcium channel genes. A study of these diseases illustrates the kind of insights into calcium channel function that can be expected from this method of inquiry. 相似文献