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81.
82.
The Function of the Hilum in Some Papilionaceae in Relation to the Ripening of the Seed and the Permeability of the Testa 总被引:4,自引:1,他引:4
In seeds of Trifolium repens, T. pratense, and Lupinus arboreus,the hilum is a hygroscopically activated valve in the impermeableepidermis of the testa. When relative humidity was low the fissurein the hilum opened permitting the seed to dry out; when therelative humidity was high the fissure closed obstructing theabsorption of moisture. During seed-ripening the moisture contentfell readily to approximately 25 per cent., and thereafter moreslowly until the epidermis became impermeable at approximately14 per cent, moisture content. Further drying of the seed tookplace only by diffusion of water vapour through the hilum. Hardseeds tended to have a moisture content in equilibrium withthe lowest relative humidity to which they had been exposed.They absorbed moisture under conditions of gradually increasingrelative humidity such that the hilar fissure remained open.The duration of the impermeable condition increased with thedegree of desiccation brought about by loss of water throughthe hilum. 相似文献
83.
O Djoseland 《Steroids》1976,27(1):47-64
The in vivo and in vitro metabolism of 3H-testosterone by rat epididymis and the changes in epididymal weight have been studied after castration and treatment with anti-androgens. The utilization of 3H-testosterone was greatly reduced after castration as was the formation of 5alpha-reduced 17 beta-hydroxy metabolites. The formation of the 17 -keto metabolites was unaffected. Castration had no effect on the ratio between water and ether soluble radioactivity. Administration of testosterone propionate, necessary for giving normal stimulated prostate weight (150 mug/day), restored the metabolism of testosterone to approximately normal values. Estradiol benzoate and progesterone inhibited metabolism of testosterone in vitro and greatly reduced the formation of DHT (17 beta-hydroxy-5alpha-androstan-3-one) and 3 alpha-diol(5 alpha-androstane-3 alpha-17 beta-diol) by experiments both in vivo and in vitro. No effect of cyproterone acetate could be demonstrated on either the in vitro or in vivo metabolism of testosterone. Castration for 14 days reduced the epididymal weight to about 30% of that found in intact animals. Administration of testosterone propionate restored the epididymal weight to about 80% of normal. Estradiol benzoate and cyproterone acetate given to intact rats led to a decrease in the epididymal weight. Progesterone had no such effect. In 14 days castrated rats receiving testosterone propionate all three anti-androgens reduced the weight of the epididymis. In conclusion, our results show that the metabolic conversion of testosterone in epididymis to DHT and 3 alpha-diol is dramatically dependent on the hormonal status of the animal; castration or treatment with anti-androgens causes a reduced formation of the "active" androgens whilst testosterone replacement treatment restores the metabolism of testosterone to normal. 相似文献
84.
The present study elucidates the possibilities to diagnose and classify urothelial tumors of the upper urinary tract by means of exfoliative cytology on voided urine using a membrane filter method. In a series of 30 patients with renal pelvic tumors and 13 patients with ureteral tumors an overall agreement between cytology and histopathology was obtained in 25 cases (58%). None of the Grade 1 tumors or of the non-invasive Grade 2 tumors were regarded as positive by cytology whilst two out of five invasive Grade 2 tumors had positive cytologic reports. The series included 24 patients with poorly differentiated or anaplastic tumors, 17 of whom had positive cytology (71%). By excluding from the series 13 patients with obstructed urinary passages or radiologically non-functioning kidneys on the tumor side an agreement between cytology and pathology was reached in 83 per cent of the cases, regardless of tumor grade, and in 17 out of 18 patients with Grade 3-4 tumors (94%). 相似文献
85.
86.
87.
Aspergillus tamarii Kita grown in media that contained single soluble or insoluble cellulosic sources of carbon, released a complex of cellulolytic enzymes into the medium. The complex was separated into thirteen components by gel filtration followed by ion exchange chromatography. Eight of the components had a high molecular weight and five had a low molecular weight. One of the high molecular weight components, designated Ab, had the character of C1 cellulase enzyme. In a few cases there was synergism between the components, since in combination they liberated more glucose than when alone. 相似文献
88.
Ohne ZusammenfassungMit 3 Textabbildungen.Zweite Mitteilung der Untersuchungen über die physiologischen Grundlagen der Dürreresistenz des Botanischen Instituts der Technischen Hochschule Darmstadt. Dem Deutschen Forschungsrat und der Deutschen Forschungsgemeinschaft danken wir für die Bereitstellung von Mitteln und die Gewährung eines Stipendiums. 1. Mitteilung:H. Schmidt: Plasmazustand und Wasserhaushalt beiLamium maculatum. Protoplasma33, 25 (1939). 相似文献
89.
gamma-Glutamyl transpeptidase: a single copy gene in the rat and a multigene family in the human genome 总被引:5,自引:0,他引:5
A Pawlak O Lahuna F Bulle A Suzuki N Ferry S Siegrist N Chikhi M N Chobert G Guellaen Y Laperche 《The Journal of biological chemistry》1988,263(20):9913-9916
gamma-Glutamyl transpeptidase (GGT) genomic sequences were isolated from rat and human libraries using a rat GGT cDNA as a cross-species hybridization probe. Characterization of the human GGT clones by restriction mapping clearly establishes that at least four different GGT genes or pseudogenes are present in the human genome. All the rat genomic clones cover a 12.5-kilobase sequence and exhibit a unique restriction pattern. A precise quantitation of the rat GGT gene copy number by Southern blot analysis demonstrates that this sequence is present as a single copy/rat haploid genome. Therefore, the GGT gene organization is different between rat and human species; this raises the possibility of different regulatory mechanisms in the two species. 相似文献
90.
The botanical composition and the ratio of various plants in the diet of Microtus socialisPall. were determined by microhistological cuticular-coprological analysis of undigested remains. Microtus socialis disappeared from the zonal plain of the Volga-Ural interfluve in the early 1970s and appeared again in 2009. The role of grains in their nutrition became more important, and the ratio of wormwoods sharply decreased. The feeding patterns observed are caused by the long-term absence of these massive phytophages and reflect significant changes in the habitat over the last 40 years. 相似文献