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51.
52.
Indole compounds secreted byFrankia sp. HFPArI3 in defined culture medium were identified with gas chromatography-mass spectrometry (GC-MS). WhenFrankia was grown in the presence of13C(ring-labelled)-L-tryptophan,13C-labelled indole-3-acetic acid (IAA), indole-3-ethanol (IEtOH), indole-3-lactic acid (ILA), and indole-3-methanol (IMeOH) were identified.High performance liquid chromatography (HPLC) and GC-MS with selected ion monitoring were used to quantify levels of IAA and IEtOH inFrankia culture medium. IEtOH was present in greater abundance than IAA in every experiment. When no exogenous trp was supplied, no or only low levels of indole compounds were detected.Seedling roots ofAlnus rubra incubated in axenic conditions in the presence of indole-3-ethanol formed more lateral roots than untreated plants, indicating that IEtOH is utilized by the host plant, with physiological effects that modify patterns of root primordium initiation. 相似文献
53.
Effect of capsulectomy on the hemodynamics and viability of random-pattern skin flaps raised on expanded skin in the pig 总被引:2,自引:0,他引:2
S F Morris C Y Pang J Mahoney N Lofchy I L Kaddoura R Patterson F Lista 《Plastic and reconstructive surgery》1989,84(2):314-22; discussion 323-4
Skin flaps constructed on expanded skin usually include the underlying capsular tissue. It has been hypothesized that capsulectomy may jeopardize the viability of the expanded skin flap. The experiments reported herein were designed to test this hypothesis. Specifically, we studied the hemodynamics and viability of random-pattern skin flaps (8 X 20 cm) raised on delayed bipedicle flaps (group A) and on expanded skin pockets with capsulectomy at the time of flap elevation (group B) or with intact underlying capsular tissue (group C). Each group was randomly assigned to each flank in 16 pigs. Skin pockets were expanded by inflation of subcutaneous silicone tissue expanders with sterile saline (299 +/- 7 ml; X +/- SEM) over a period of 3 weeks. At the end of this period, the bipedicle flaps were constructed. Eight days later, random-pattern skin flaps were raised on bipedicle flaps and skin pockets. The length and area of skin flap viability, judged by the fluorescein dye test performed 1 day postoperatively, were not significantly different (p greater than 0.05) among groups A, B, and C (n = 31 to 32). There also were no significant differences (p greater than 0.05) in total skin capillary blood flow measured 1 day postoperatively (A = 2.6 +/- 0.4, B = 2.4 +/- 0.4, and C = 2.7 +/- 0.6 ml/min per flap; n = 15 to 16) and in skin viability assessed 7 days postoperatively (A = 74 +/- 2, B = 75 +/- 2, and C = 76 +/- 2 percent; n = 16) among delayed skin flaps and skin flaps raised on expanded skin pockets with or without capsulectomy. The results of this flap viability study were confirmed in 5 minipigs in a separate experiment. We conclude that capsulectomy did not have a detrimental effect on the hemodynamics and viability of random-pattern skin flaps raised on expanded skin. Furthermore, we hypothesize that skin flaps raised on expanded skin are similar to delayed skin flaps in that the skin blood flow is optimally augmented; therefore, the capsular tissue does not add significant blood supply to the overlying skin. 相似文献
54.
6 beta-Hydroxyaldosterone and 6 beta-hydroxy-17-isoaldosterone, characterized by high-field NMR studies, are among the major polar metabolites formed from aldosterone by incubation with rat liver slices or microsomal fraction. It is uncertain at present whether the 17-iso product results from an enzymatic or a chemical inversion of configuration. Periodate degradation of the 6 beta-hydroxyaldosterone gave 6 beta-hydroxyaldosterone gamma-lactone, identical with a synthetic sample. 相似文献
55.
K. J. Morris K. M. S. Townsend A. L. Batchelor 《Radiation and environmental biophysics》1989,28(2):141-154
Summary Seventy-three rats were exposed to an aerosol of enriched uranium dioxide (UO2), giving initial lung burdens of 26 to 447 µg at 6 days post-inhalation (PI). At 7 days PI 35 of these rats were further exposed to thermalised neutrons at a fluence of 1 x 1012 neutrons CM–2. There was no significant difference between the two groups in the clearance rate of the UO2 particles from the lung, up to 590 days PI. The particles cleared relatively slowly over this period with a retention halftime in the lung of 160 to 176 days.Transmission electron microscope (TEM) studies of tissue from the alveolar region at 8 days PI showed that inhalation of UO2 particles significantly increased the sizes of macrophage and type II cells, and the number of macrophage and type I cells. There was also a significant increase in the size of lysosomal granules within the macrophages after exposure to the UO2 particles. The exposure to UO2, neutrons and235U fission fragments had no significant effect on any of the cells above that observed in the animals exposed to UO2 alone.Additional rats were exposed to the same neutron fluence without prior UO2 inhalation. The alveolar cells of neutron-only exposed rats were, in size and number, typically no different from those in the completely unexposed control rats. 相似文献
56.
Macvicaria obovata (Molin) n. comb. is redescribed from Sparus aurata off the Mediterranean coast of France and a neotype is designated. Specimens from Oblada melanura off Israel may belong to the same species. It is mainly characterized by the uterine extension between the ovary and the anterior testis and the lack of a vitelline confluence in the forebody. M. maillardi n. sp. is also described from Sparus aurata off the southern coast of France. Its uterus does not pass between ovary and testes and the vitelline fields are confluent in the forebody. M. crassigula (Linton) n. comb. is redescribed from Diplodus annularis, D. sargus, D. vulgaris, Pagellus erythrinus and Sparus pagrus off Corsica, Calamus bajonado off Bermuda, Spicara smaris, D. annularis off Yugoslavia, D. sargus off Israel, and D. cervinus, Sparodon durbanensis and Cheilodactylus fasciatus in the SW Indian Ocean. It is similar to M. maillardi, but differs in being smaller, having a greater sucker ratio and a larger pharynx. It may well be a species-complex. M. dubia (Stossich) n. comb. is redescribed from Oblada melanura off Corsica and Yugoslavia. It is similar to M. maillardi and M. crassigula, but has a more anteriorly situated genital pore. 相似文献
57.
A new species, Neolepidapedon smithi, is described from the fish Mora moro in the north-eastern Atlantic Ocean and is distinguished from other members of the genus. It differs from its congeners in the extension of the vitellarium into the forebody and/or the body shape. The genus Neolepidapedon is reviewed and a key to species given. The genus has previously contained up to 20 species, but is here restricted to eight species, which possess a very thick male duct wall within the cirrus-sac, a narrow internal seminal vesicle, an excretory vesicle restricted to the hindbody and no eye-spots. The remaining nominal species with a relatively thin-walled internal male duct, a globular internal seminal vesicle, an excretory system which reaches into the forebody and eye-spots are considered to belong to a separate group which is related to Opechona. Some of these species were included by Yamaguti (1971) in his new subgenus Neolepidapedon (Neolepidapedoides), which is raised to full generic status. Eight new combinations are made: Neolepidapedoides belizensis (Fischthal, 1977), N. dollfusi (Durio & Manter, 1968), N. equilatum (Siddiqi & Cable, 1960), N. hypoplectri (Nahhas & Cable, 1964), N. israelense (Fischthal, 1980), N. macrum (Overstreet, 1969), N. medialunae (Montgomery, 1957) and N. mycteropercae (Siddiqi & Cable, 1960). 相似文献
58.
The human BCR gene on chromosome 22 is specifically involved in the Philadelphia translocation, t(9;22), a chromosomal rearrangement present in the leukemic cells of patients with chronic myeloid leukemia or acute lymphoblastic leukemia. In most cases, the breakpoints on chromosome 22 are found within a 5.8 kb region of DNA designated the major breakpoint cluster region (Mbcr) of the BCR gene. Hybridization experiments have indicated that the human genome contains BCR gene-related sequences. Here we report the molecular cloning of one of these loci, for which we propose the name ABR. In contrast with the other BCR-related genes studied to date, ABR represents a functionally active gene and contains exons very similar to those found within the Mbcr. Unlike the BCR gene, the ABR gene exhibits great genomic variability caused by two different variable tandem repeat regions located in two introns. All other BCR gene-related sequences isolated so far and the BCR gene itself are located on chromosome 22. In contrast, the ABR gene is located on chromosome 17p. 相似文献
59.
The skin from rats of differing age was used to quantify variations in the cell kinetics of the epidermis and the follicular epithelium of different body sites. Four parameters were assessed, namely the basal cell density (BCD), the labelling index (LI), the duration of DNA synthesis (ts) and the basal cell turnover time (tT). The BCDs of the epidermis of the dorsum and the upper surface of the foot were similar in rats of 7, 14 and 52 weeks of age, but there was an indication of a progressive decline with increasing age in the BCD of the epidermis of the ear and tail. There were no age-related changes in the length of ts in any of the four body regions. The rate of cell proliferation, as indicated by the values of the LI and tT, was relatively rapid in the epidermis of the dorsum, foot and tail of rats aged 7 weeks (LI greater than 12%; tT less than 80 h). In rats aged 14 weeks this rate of proliferation was maintained in the epidermis of the dorsum. However, in the foot and tail the rate of cell proliferation was decreased (LI less than 10%; tT greater than 85 h). A fall in the rate of proliferation of the epidermis of the dorsum was only seen in 52-week-old animals. In these animals the rates of proliferation in the foot and tail were similar to those at the age of 14 weeks. In the epidermis of the ear there was no appreciable change in the rate of cell proliferation with age. The values of the cell kinetic parameters varied in the different body sites. For example, in 52-week-old animals values for tT were relatively short in the epidermis of the tail and foot and appreciably longer in the epidermis of the dorsum and ear. Considered overall, values for the cell kinetic parameters of the epidermis were comparable with those for the follicular epithelium. The only major differences between the epidermis and the follicular epithelium were in the upper surface of the foot at 7 weeks of age, and in the tail at 7 and 14 weeks of age, where the LI was higher and the tT shorter in the epidermis than in the follicular epithelium. The relevance of the observed age- and body-site-related variations in the cell kinetics of the epidermis are discussed in relation to previously described differential changes in the radiosensitivity of the skin in this strain of rat. 相似文献
60.
Nutritional and hormonal regulation of mRNA abundance for arginine biosynthetic enzymes in kidney 总被引:2,自引:0,他引:2
Argininosuccinate synthetase and argininosuccinate lyase catalyze the synthesis of arginine from citrulline in kidney and also serve as components of the urea cycle in liver of ureotelic animals. Dietary and hormonal regulation of mRNAs encoding these enzymes have been well studied in liver but not in kidney. Messenger RNAs for these enzymes are localized within the renal cortex. Starvation and extreme variations in dietary protein content (0% vs 60% casein) produced 2.6- to 3.5-fold increases in mRNA abundance for these two enzymes in rat kidney. Argininosuccinate lyase mRNA was not induced by dibutyryl cAMP, dexamethasone, or a combination of the two agents. In contrast, argininosuccinate synthetase mRNA was induced 2-fold by dibutyryl cAMP but was unresponsive to dexamethasone. Thus, diet and hormones regulate levels of these mRNAs in rat kidney, but the responses are both qualitatively and quantitatively distinct from the responses previously reported for rat liver. 相似文献