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991.
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   
992.
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   
993.
994.
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   
995.
Use of 36Cl, 82Br, and [3H]sucrose to estimate extracellular water volume was evaluated in 14 piglets (7-14 days old). 36Cl and 82Br were distributed in approximately the same volume, but a period of 5-6 hr after injection was required to reach equilibrium in the neonatal pig. Dilution volumes calculated before equilibration (2-5 hr) for 36Cl (326 +/- 11 ml/kg) and 82Br (328 +/- 13 ml/kg) were different from equilibration (6-8 hr) phase volumes (356 +/- 13 ml/kg and 355 +/- 13 ml/kg, respectively; P less than 0.001). A 3-hr sample estimated the same volume distribution calculated by extrapolation of the 6- to 8-hr period because of the relationship between the two slopes of the plasma clearance curves. After the 82Br and 36Cl had achieved equilibration, each was distributed in a volume equivalent to total body chloride space (362 +/- 29 ml/kg) measured by neutron activation; no statistical differences were found (P = 0.6). The early equilibration phase measured a 10% smaller, faster exchangeable fraction of total body Cl. Sucrose dilution volume (332 +/- 19 ml/kg) required multiple plasma samples for extrapolation and measured a dilution volume 7% smaller (P less than 0.05) than total body chloride space.  相似文献   
996.
In experiments with rats it was shown that with equal absorbed doses after single injection of 137Cs and local X-irradiation of testes the mutation yield in gametes was different when tested by the frequency of dominant lethals and half-lethals, reciprocal translocations, univalents, and chromosome fragments. A higher efficiency of whole-body irradiation as compared to local exposure of testes, with respect to genetic damages induction, and the statistically significant increase in the number of the damages during a long period of time after cessation of the absorbed dose formation indicated that indirect effects of whole-body irradiation contributed to the injury to hereditary structures and permitted to estimate approximately their contribution (up to 50%).  相似文献   
997.
Haemoglobin leakage and permeability for 86Rb and K ions during storage at normal and hypothermic conditions have been investigated in the erythrocytes of the ground squirrel Citellus undulatus in hibernating, arousing and awake animals, as well as in rats. During hibernation, stabilization of the barrier properties and a decrease in passive ionic permeability of erythrocyte membrane were observed. Preservation of ionic homeostasis of the erythrocytes in hibernating animals is favoured by activation of Na(+)-pump. By means of radioautography of electrophoregrams of the blood serum proteins, appearance of a rapidly labeling low-molecular protein was noted at the beginning of the baut and its disappearance before arousal. The data obtained are discussed in relation to the role of the blood plasma components in modification of erythrocyte membranes in hibernating animals.  相似文献   
998.
In the paper changes of active electrogenesis of the command neurones of defensive closure of snail pneumostome at elaboration, extinction and repeated elaboration of classic conditioned defensive reflex to tactile stimulus was described; the tactile stimulation of other point of the body served as a differentiating stimulus. During the increase of biological significance of conditioned stimulus as a result of learning the stimulation of the command neurones in response to this stimulus was raised. At the same time the neurones showed decreased excitability in response to differentiating stimulus. Possible mechanisms of quick reconstruction of neurones excitability and functional value of PA generation threshold changes were discussed.  相似文献   
999.
The development of the Drosophila R7 photoreceptor cell is determined by a specific inductive interaction between the R8 photoreceptor cell and a single neighboring precursor cell. This process is mediated by bride of sevenless (boss), a cell-surface bound ligand, and the sevenless (sev) tyrosine kinase receptor. The boss ligand is expressed specifically on the surface of the R8 cell, whereas the sev receptor is expressed on 5 cells contacting the developing R8 cell and other cells not in contact with R8. By altering the spatial and temporal expression of boss, we demonstrate that sev-expressing cells that do not contact R8 can assume an R7 cell fate. By contrast, the sev-expressing precursor cells to the R1-R6 photoreceptor cells that do contact R8 are nonresponsive to the inductive cue. Using the rough and Nspl mutations, we demonstrate that an early commitment to an R1-R6 cell fate blocks the pathway of sev activation in these cells.  相似文献   
1000.
A method which employs the polymerase chain reaction (PCR) to identify Escherichia coli strains containing the estA gene was developed. This gene codes for heat-stable enterotoxin type I. The use of an inosine-containing pair of amplification primers allowed the amplification of a specific 175-bp DNA fragment from several different estA alleles. The amplified fragments were identified and distinguished by allele-specific oligonucleotide hybridization and characterized by restriction endonuclease analysis. An extension of the classical two-primer PCR proved to be a very simple and rapid method to identify and characterize the estA alleles. Besides the inosine-containing pair of primers, which recognized all described alleles, additional oligonucleotides were used as primers. The sequence of each of these primers was allele specific, and each was amplification compatible with one of the inosine-containing primers. Thus, in one PCR the 175-bp fragment typical for all estA alleles and an allele-specific fragment of different size were produced. These fragments could be separated by agarose gel electrophoresis and were recognized by ethidium bromide staining. Twenty-seven E. coli strains were tested with this amplification system. The presence or lack of the genetic information for production of heat-stable enterotoxin type I was perfectly consistent with the ability of these strains to produce this enterotoxin, as determined by enzyme-linked immunosorbent assay.  相似文献   
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