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991.
V A Tronov V A Za?tsev D I Cherny? A N Koterov I V Filippovich 《Molekuliarnaia biologiia》1991,25(1):212-222
Binding of SSB-protein from Ehrlich ascites tumor to ssDNA from M13 phage leads to its compactization. The structure of the complex at the protein/DNA ratios far from the saturation level looks like "beads-on the string". DNA that was fully saturated with protein forms collapsed globular structure. Binding of the protein to the dsDNA from phage lambda increases its flexibility and decreases the coil dimensions; no "beads-on the string" structure are seen. The protein possess slight destabilizing effect on hairpin helices of M13DNA. Competition studies demonstrate that the binding properties of protein with polyribonucleotide lattices and DNA's decrease in ranking as follows: poly(rG) greater than or equal to poly(rI) greater than or equal to ssDNA greater than dsDNA greater than poly(rA) congruent to approximately poly(rU). Thus SSB-protein from Ehrlich ascites tumor differs significantly from its presumed prokaryotic analogs. 相似文献
992.
Steroidal saponins from the rhizomes of Polygonatum orientale. 总被引:6,自引:0,他引:6
993.
994.
T Kurzawiński L Ciesielski G Cie?lewicz 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(45-47):862-864
Phagocytic index and rosette test E have been determined in 50 patients, including 15 with diffuse peritonitis and the noncomplicated diffuse peritonitis, 20 patients with septic complications, and 15 patients who underwent abdominal surgery. It was found, that phagocytic index is decreased in all patients after abdominal surgery. The most marked decrease of this index was found in patients with complicated peritonitis. It still decreases in the course of peritonitis and increases in the reference group. The marked decrease in the number of T-cells was observed in complicated peritonitis during the whole period of follow-up while it normalizes in case of noncomplicated peritonitis as in the reference group. Using the tests under study it was possible to assess cell-mediated immunity which is depressed in peritonitis. The tests enable also the prediction of septic complications of peritonitis. 相似文献
995.
T Robak E Krykowski L Brodowski A Zawadzka-Bandura H Urbańska-Ry? M B?asińska-Morawiec W Matusewicz 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(48-49):931-934
An efficiency of the acute myeloblastic leukemia therapy has been assessed in 79 patients aged over 60 years. Twenty six patients out of this group have been treated with usual or reduced doses of doxorubicin and cytarabine (ADR-Ara-C) 35--low doses of cytarabine (LD Ara-C), 11-6-mercaptopurine (6 MP), and 7 patients died before chemotherapy. Complete remission in group treated with ADR-Ara-C was achieved in 23% of patients while partial remission in 42%. Median survival in this group was 5.8 months (range from 0.5 to 16 months). Percentage of the complete remissions in the group treated with LD-Ara-C was 6%, and partial remissions 40%. Median survival was 4.7 months (range from 0.5 to 14.2 months). Partial remission in 5 out of 11 patients treated with 6 MP (36%) and no complete remissions were noted. Median survival was 3.9 months. Therapy with ADR-Ara-C produced marked leucopenia and thrombocytopenia in the majority of treated patients. Vomiting, hemorrhagic complications, and bacterial infections have also been noted. These adverse reactions have been less frequent in patients treated with LD-Ara-C, and 6 MP. Ten patients (38%) treated with ADR-Ara-C and 7 patients treated with LD-Ara-C died during remission inducing therapy. 相似文献
996.
A Szyszka D Nowak A Ponizyński A Cie?liński Z Brocki 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(6-7):109-111
An average follow-up period of 16 patients was 28 months following an implantation of the artificial aortic valve for its insufficiency. In 10 operated patients who were able to continue their occupation exercise tolerance increased by two classes, according to NYHA. Blood pressure gradient decreased significantly from 61.8 to 37.5 mmHg, cardiac volume index decreased from 639 to 602 ml/m2. Echocardiographically measured muscle mass of the left ventricle, end-diastolic and end-systolic volumes, and the left atrial dimensions decreased significantly following surgery. A significance of the relation of the left ventricle volume to its mass <4 as a prognostic factor in aortic valve replacement has also been confirmed. 相似文献
997.
998.
J Fibak A J Onyszkiewicz K S?owiński W Burchardt J Kolasiński 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(45-47):869-871
Recurrence of duodenal ulcer was diagnosed in 15 patients who underwent highly selective vagotomy before 6-13 years, i.e. in 12.2%. Factors possibly contributing to such a recurrence were analysed. Patients with ulcer recurrence were: 1) non-qualified workers, 2) tobacco smokers, 3) heavy drinkers, 4) users of ulcerogenic medicines, and 5) were involved into conflict situations. 相似文献
999.
Flooding is a frequently occurring environmental stress that can severely affect plant growth. This study shows that treatment of corn (Zea mays L.) seedlings with abscisic acid (ABA) increases their tolerance to anoxia 10-fold over untreated seedlings and twofold over seedlings treated with water. Corn seedlings stressed anoxically for 1 day showed only 8% survival when planted in vermiculite. Pretreatment of root tips with 100 micromolar ABA or water for 24 hours before the 1 day anoxic stress increased the anoxic survivability of seedlings to 87% and 47%, respectively. Cycloheximide (5 milligrams per liter), added together with ABA, reduced the seedling survival rate, indicating that the induction of anoxic tolerance in corn by ABA was partly a result of the synthesis of new proteins. ABA treatment induced a threefold increase in alcohol dehydrogenase enzyme activity in corn roots. However, after 24 h of anoxia, alcohol dehydrogenase enzyme activity between the ABA-pretreated and non-pretreated corn roots was not significantly different. The results indicated that ABA played an important role in inducing anoxic tolerance in corn and that the induced tolerance was probably mediated by an increase in alcohol dehydrogenase enzyme activity before the anoxic stress. 相似文献
1000.
Terminal meristems of Pisum sativum (garden pea) transit from vegetative to inflorescence development, and begin producing floral axillary meristems. Determination for inflorescence development was assessed by culturing excised buds and meristems. The first node of floral initiation (NFI) for bud expiants developing in culture and for adventitious shoots forming on cultured meristems was compared with the NFI of intact control buds. When terminal buds having eight leaf primordia were excised from plants of different ages (i.e., number of unfolded leaves) and cultured on 6-benzylaminopurine and kinetin-supplemented medium, the NFI was a function of the age of the source plant. By age 3, all terminal buds were determined for inflorescence development. Determination occurred at least eight nodes before the first axillary flower was initiated. Thus, the axillary meristems contributing to the inflorescence had not formed at the time the bud was explanted. Similar results were obtained for cultured axillary buds. In addition, meristems excised without leaf primordia from axillary buds three nodes above the cotyledons of age-3 plants gave rise to adventitious buds with an NFI of 8.3 ±0.3 nodes. In contrast seed-derived plants had an NFI of 16.5 ±0.2. Thus cells within the meristem were determined for inflorescence development. These findings indicate that determination for inflorescence development in P. sativum is a stable developmental state, separable from determination for flower development, and occurring prior to initiation of the inflorescence at the level of meristems. 相似文献