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1.
Carolyn M. Giles Beatrice Uring-Lambert Joelle Goetz Georges Hauptmann Angela H. L. Fielder William Ollier Christian Rittner Tracy Robson 《Immunogenetics》1988,27(6):442-448
The antigenic determinants of human C4 have been defined by human IgG antisera, Rodgers (Rg) and Chido (Ch), in hemagglutination-inhibition assays (HAI). Eight (2 Rg and 6 Ch) are of high frequency, > 90% , and 1, WH, is of low frequency, 15 %. The phenotypic combinations are complex; generally, C4A expresses Rg, and C4B has Ch, but reverse antigenicities have been established both by HAI and by sequence data of selected C4 allotypes. A study of 325 families provides data on the antigenic expression of each C4 allotype and demonstrates strong associations. A structural model for the antigenic determinants of C4 proteins has been proposed and is completely supported by the family material. Of the 16 possible antigenic combinations for C4 proteins, only 3 are undetected. A new Ch combination has been recorded in two French families. The reported sequence variation within the C4d region can account for the antigenic determinants but leaves the location of electrophoretic variation in C4 still unclear. 相似文献
2.
Boon Seng Ooi Beatrice T. M. Chen Charles C. S. Toh Oon Teik Khoo 《BMJ (Clinical research ed.)》1970,3(5725):744-746
Of 127 hypertensive patients aged 12 to 40 investigated by intravenous pyelography, abdominal aortography, and renal biopsy an underlying cause was found in 57%. The proportion with secondary hypertension was higher in young patients and in those with severe hypertension. Primary arteritis of the aorta was an important cause of renovascular hypertension in an Asian population. 相似文献
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J. Woodland Hastings Lazarus Astrachan Beatrice M. Sweeney 《The Journal of general physiology》1961,45(1):69-76
The luminescent marine dinoflagellate, Gonyaulax polyedra, exhibits a diurnal rhythm in the rate of photosynthesis and photosynthetic capacity measured by incorporation of C14O2, at different times of day. With cultures grown on alternating light and dark periods of 12 hours each, the maximum rate is at the 8th hour of the light period. Cultures transferred from day-night conditions to continuous dim light continue to show the rhythm of photosynthetic capacity (activity measured in bright light) but not of photosynthesis (activity measured in existing dim light). Cultures transferred to continuous bright light, however, do not show any rhythm. Several other properties of the photosynthetic rhythm are similar to those of previously reported rhythms of luminescence and cell division. This similarity suggests that a single mechanism regulates the various rhythms. 相似文献
5.
Haemoglobins of invertebrate tissues. Nerve haemoglobins of Aphrodite, Aplysia and Halosydna 总被引:1,自引:0,他引:1 下载免费PDF全文
1. The occurrence of haemoglobin in invertebrate nerves is surveyed. Haemoglobin was observed in the nerves and ganglia of the marine nematode Amphiporus sp. and of the polychaet annelid Halosydna sp. 2. Haemoglobins from the nerve and ganglia of the polychaet annelid Aphrodite aculeata L. and from the nerve of the gastropod mollusc Aplysia californica have been partially purified. The haem in each case was identified as iron protoporphyrin IX. 3. The minimum molecular weight of Aphrodite nerve haemoglobin deduced from the haem content and amino acid analysis is 17090, in agreement with the molecular weight 15600+/-1000 determined by sedimentation equilibrium. 4. The molecular weight of Aplysia nerve haemoglobin was determined by sedimentation equilibrium to be 16400+/-1000. 5. The oxygen dissociation curves are hyperbolic. Half-saturation is achieved at 1.1mm. Hg for Aphrodite nerve haemoglobin and at 4.0mm. Hg for Aplysia nerve haemoglobin. The coefficients for partition between carbon monoxide and oxygen are: Aphrodite nerve haemoglobin, 167; Aplysia nerve haemoglobin, 116. 6. The ferrous haemoglobins combine with cyanide. 7. We conclude that the intracellular haemoglobins of muscle and nerve are similar. 相似文献
6.
Christa Grossniklaus-Buergin Jean-Louis Connat Beatrice Lanzrein 《Archives of insect biochemistry and physiology》1989,11(2):79-92
In unparasitized 4th and 5th-instar larvae of Trichoplusia ni and in 4th-instar larvae parasitized by Chelonus sp. 20-hydroxyecdysone, 20,26-dihydroxyec-dysone, and 20-hydroxyecdysonoic acid were the predominant metabolites formed 2 h after injection of [3H]ecdysone. Other unidentified metabolites were seen, but none seemed to be specific for either parasitized or unparasitized larvae. The major difference between parasitized and unparasitized larvae was seen with respect to the quantity of apolar (unidentified) and polar metabolites (20-hydroxyecdysonoic acid and unidentified ones), which were produced to a greater extent in parasitized larvae. Ecdysone was rapidly converted into 20-hydroxyecdysone and the other polar metabolites in all stages investigated, and the parasitoid seemed not to affect the conversion of ecdysone into 20-hydroxyecdysone. When analyzing the fate of [3H]ecdysone in host and parasite separately, at a stage when the parasite drinks hemolymph of its host, we observed that 10–20% of the radioactivity was recovered from the parasitoid. Analysis of the parasitoid's ecdysteroids revealed that ecdysone and 20-hydroxyecdysone represented only a small proportion of the recovered labeled ecdysteroids, the majority being apolar and polar metabolites. Our data suggest that the parasitoid takes up ecdysteroids from its host, converts them, and to some extent releases apolar metabolites into the host. 相似文献
7.
Walter R. Meyer Beatrice Lanzrein 《Archives of insect biochemistry and physiology》1989,10(4):317-331
In vitellogenic females of Nauphoeta cinerea, injected (10R)-juvenile hormone (JH) III was degraded more rapidly than racemic JH III: we measured a half-life of 21 min (with or without coinjection of lipophorin) for the former and 24 min (with coinjection of lipophorin) and 43 min (without coinjection of lipophorin) for the latter. One to two hours after injection, JH III acid was the major metabolite observed; in addition, several highly polar products were found. The half-life of injected racemic JH III acid was 19 min with coinjection of lipophorin and 4 min without. The JH III acid titer in hemolymph was low (around 5–10 pmol/ml) in last instar larvae and previtellogenic and pregnant females and reached higher values (40–100 pmol/ml) in vitellogenic and ovulating females. Racemic JH III acid could be methylated in vitro to JH III by corpora cardiaca–corpora allata (CC-CA) from penultimate instar larvae and females at stages between adult ecdysis and ovulation and at the very end of pregnancy, but not by CC-CA from last instar larvae and adult females at earlier stages of pregnancy. This indicates that CC-CA are capable of methylating JH III acid only at stages when JH III is detectable in the hemolymph. In double-labelling experiments with CC-CA from vitellogenic females and L-[14C]methionine and [3H]JH III acid as precursors, we observed that only a small proportion (1–8%) of total biosynthesized JH III was derived from JH III acid when the latter was present at physiological concentration. This suggests that in vivo recycling of JH III acid by CC-CA plays only a minor role in the regulation of the titer of JH III and JH III acid. 相似文献
8.
We present a list of Italian freshwater and marine Oligochaeta in the families Lumbriculidae, Haplotaxidae, Tubificidae, Naididae, Propappidae, Criodrilidae, and Lumbricidae, representing 57 genera and 130 species. Published data reflect the incomplete knowledge of the Italian oligochaete fauna, restricted to certain geographical areas. Subterranean aquatic and marine fauna are of particular interest as these have been studied the least. We provide a comprehensive review of the Naididae including, for the first time, southern Italy and the islands of Sicily and Sardinia. The distribution of species is discussed and taxonomic problems arising from the morphological variability of Italian material are examined. 相似文献
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