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Diastereomers of the title compound were obtained and absolute configuration was assigned by means of stereochemical correlation. Their reaction with 3'-O-methoxyacetylthymidine in the presence of triisopropylbenzenesulphonyl (4-nitro) triazole is neither chemo- nor stereo-selective and leads to diastereomeric pairs of dithymidyl (3',5')methanephosphonate and -methanephosphonothioate. Obtained results are discussed in terms of mechanism of activation of phosphodiesters under conditions known as "phosphotriester approach to oligonucleotide synthesis".  相似文献   
44.
Results of investigations carried out in a 500-person group of patients with stoma and their practical applications are discussed. 1. Despite operational shock, the majority of patients is able to adopt to the new situation and develop different life-style. 2. Rehabilitation facilities pre-operational management and provides an information on stoma before surgery. Postoperative management should consider psychosocial aspects of the stoma. 3. An important role in rehabilitation process play: preparation of the patients' families before the surgery including information on the diagnosis, prognosis and planned therapy. 4. Persons who underwent the same surgery and continue active life may favourably contribute to the postoperational care of patients with stoma. Activity of so-called patients clubs plays also positive role.  相似文献   
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An effect of the treatment with guanfacine on the activity of the adreno-sympathetic system, beta-thromboglobulin, beta-endorphin, and blood lipids was studied in 30 patients with the primary arterial blood hypertension. It was found that guanfacine significantly decreases plasma noradrenaline, adrenaline, and dopamine. Moreover, it decreases the excretion of noradrenaline, adrenaline and 4-hydroxy-3-methoxy-phenylglycol. These effects correlate with the drop in both systolic and diastolic blood pressure. A decrease in plasma renin activity was also observed. It correlated with the blood pressure drops. Guanfacine increased beta-endorphin levels while beta-thromboglobulin, total cholesterol and triglycerides levels remained unaffected. The authors suggest that the hypotensive effect of guanfacine is related to the decrease in adreno-sympathetic system activity and plasma renin activity and no effect on the erythrocyte activity and lipids metabolism.  相似文献   
47.
Under tolerance, evoked by multiple doses of pethidine (PD), the serum and brain tissue content of PD was related to diminished analgesic activity. Even though in tolerant rats no enhancement of PD biotransformation in the liver could be recognized (as followed by the measurement of hepatic esterase and N-demethylase activity), the amounts of both PD and nor-PD excreted in urine were increased under tolerance. The authors conclude that the faster disposition of PD may contribute to the development of tolerance.  相似文献   
48.
Most of the biological processes in the living organisms of both animals and man are known to be of rhythmical nature. Variability of enzymatic activity in circadian cycle depends on many factors among other on age, sexual maturity, diet as well as medication. The results obtained in our studies indicate, that the activity changes of acid phosphatase and ATP-ase Mg++ dependent in the liver of all the examined age groups were of 24 hour circadian rythm. As to the acid phosphatase activity the results of this experiments showed that in circadian cycle in all examined age groups there is only one peak of elevated activity. ATP-ase Mg++ dependent showed two activity peaks appearing at the same hour both in 30 and 60 days old animals. It should be noticed that the activities of ATP-ase Mg++ dependent in 100 day old animals were two times higher than in 30 and 60 days old rats.  相似文献   
49.
The severe strain of potato spindle tuber viroid (s-PSTV) as well as chrysanthemum stunt (CSV) and cucumber pale fruit (CPFV) viroids were found to be transmitted through seed and pollen of the tomato cvs. Rutgers and Najwcze?niejszy. Plants pollinated with a pollen infected with any of these three viroids became systematically infected. Plant, fruit and seed symptoms of viroid infection were noted on sap- and pollen-inoculated plants and the yield of these plants was reduced. Tomato cv. Rutgers plants grown from infected seeds were symptomless although all three viroids were detected in these plants by bioassay and by electrophoresis on 5% polyacrylamide gel. When DNA complementary to s-PSTV RNA was used for a direct viroid detection in seed samples by spot hybridization technique it hybridized not only with s-PSTV RNA but also with CSV RNA as well as with CPFV RNA.  相似文献   
50.
Majority of pituitary tumours secrete one of the named hormones: PRL, GH, ACTH, proopiomelanocortine, alpha and beta subunit of TSH, LH, and FSH. Some of those tumours secrete two or more hormones. The aim of this study was to determine the effect of bromocriptine (Parlodel MR and LAR) upon secretion of hormones and tumour size in 10 patients with mixed pituitary tumours. In all patients pituitary and peripheral hormones, CT scan and visual fields were examined before and after treatment with bromocriptine: Parlodel MR and LAR. Bromocriptine treatment decreased PRL secretion in all 10 patients; GH--in all 6 in whom it was increased; TSH--in 2, FSH--in 2 and alpha-subunit in all 6 in whom they were increased. In 5 patients treatment resulted in shrinkage of the tumour mass by 20 to 35%. In all examined subjects clinical improvement was achieved. Our results demonstrate that bromocriptine (Parlodel MR and LAR) is very effective and well tolerated in the treatment of patients with mixed pituitary tumours particularly those with hyperprolactinemia.  相似文献   
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