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N N Tkachenko

Publications and source records attributed to N N Tkachenko.

18 recordsLinked to original sources
PubMed1998

Compression stimuli increase the efficacy of breast pump function.

OBJECTIVE: The dynamics of milk ejection and also prolactin concentration in the blood during milk expression by means of a breast pump were studied in 82 lactating women. STUDY DESIGN: The design of the breast pump used in this study is new. It is based on the correlation with the amplitude, duration and frequency of vacuum and compression stimuli formed by the baby's mouth apparatus during the suckling process. RESULTS: It was found that during continuous co-action of the vacuum and compression stimuli at a frequency of 1 cycle per second, the rate of milk ejection from the breast changed periodically. The highest rates of milk ejection coincided with the greatest rises in intramammary pressure. When the compression stimulus was turned off, leaving only the vacuum, the period of the first rise in pressure increased 1.5-2 fold, with a 1.5-2 fold reduction in the milk ejection rate as compared with the normal function of the breast pump. The basal prolactin level on day 3 and 5 post delivery in women who used a breast pump was not significantly different from that of puerperal women who only breast-fed their babies. Prolactin concentration in the blood of puerperal women did not change within the 5-6 min of expression and stimulation with the breast pump. The prolactin level began to increase by the 10th minute, whereas by the 25th minute it exceeded the initial concentration 1.3-1.5-fold. CONCLUSION: It is suggested that by introducing a tactile component to the mechanism of the breast pump, milk secretion is enhanced, as well as stimulating the breast milk flow. This directly improves the dynamics of breast milk expression.

Adolescent↗
PubMed1994

[Use of thermovision examination in hand burns].

With the use of thermovision set TVT-01 "Raduga" 17 healthy persons (control group) and 40 injured persons with the burn of various degree of severity were examined. In superficial I-II degree burn on the hand the temperature within the centre of injury exceeds normal level by 1.6-2 degrees C, and III A degree--by 2.2-2.6 degrees C. The healing of the burn wound was followed by gradual fall of her temperature, although she normalizes after epithelialization completion. In III B degree burn on the hand the temperature within the centre of injury decreases by 1.6-2.0 degrees C in comparison with the normal level. Autodermoplasty is effective only in the presence of temperature gradient between transplant zone and healthy tissues no more than 1.5 degrees C.

Adolescent↗
PubMed1989

[Hypothyroidism and hyperprolactinemia].

Blood thyrotropic hormone, thyroxin, tri-iodothyronine, FSH, LH, estradiol and progesterone levels were examined in 14 patients with primary hypothyroidism and 11 normal women of reproductive age. All the women under study were subjected to functional tests with intravenous thyroliberin (TRH) and metoclopramide. All hypothyroid patients had anovulatory infertility. Hyperprolactinemia was detected in 8 of 14 patients. It is demonstrated that hyperprolactinemia, developing in cases of primary hypothyroidism, is associated with impaired dopaminergic inhibition of pituitary lactotropics. Substitution thyroidin therapy resulted in the recovery of the normal ovulatory cycle in all but one patient with secondary pituitary microprolactinoma, and 8 patients became pregnant. It is believed that damaged dopaminergic regulation of hypothalamic luliberin (RH) secretion is a direct cause of ovarian dysfunction associated with primary hypothyroidism.

Adult↗
PubMedDate not supplied

[The reaction of the hypophysis to thyroliberin and metoclopramide in women with hyperprolactinemia].

Functional tests with i.v. injection of metoclopramide (10 mg) and thyroliberin (200 micrograms) with a record of PRL and TSH levels for 120 min. were performed in 87 women of reproductive age (19 healthy nonpregnant women, 9 women in the early postnatal period, 10 patients with primary hypothyroidism, and 30 patients with PRL secreting chromophobe adenomas). Hyperprolactinemic anovulation was noted in 35 examinees. Comparison of the results of thyroliberin and metoclopramide tests in different groups of examinees was suggestive of a decrease in dopaminergic inhibition of the hypophysis in postnatal and adenomatous hyperprolactinemia. The presence and a degree of hyperprolactinemia in patients with primary hypothyroidism depends, probably, on the ratio of a stimulating effect of endogenous thyroliberin and inhibitory action of dopamine on hypophyseal lactotrophs.

Adult↗
PubMedDate not supplied

[Effect of proton irradiation of the hypophysis on its gonadotropic and thyrotropic functions in patients with prolactinoma].

In order to study the effect of proton beam irradiation on prolactinoma cells and hypophyseal intact cells tests with i.v. administration of TRH (200 micrograms) and LH-RH (100 micrograms) were performed in 16 women with prolactin-secreting adenomas before and in 2 mos.-2 years after irradiation of the pituitary body with a high energy narrow proton beam (1000 MeV) at a dose of 40-120 Gy. A curative therapeutic effect of proton therapy which was low with respect to reproductive function recovery, was combined with lowered functional reserves of hypophyseal thyrotrophs and gonadotrophs. The informative value of the tests with the releasing hormones was shown for the determination of damage of hypophyseal intact cells. The results suggest refractivity of adenomatous lactotrophs to radiation exposure and the hypothalamic level of disorder of ovarian function regulation in this pathology.

Adult↗
PubMedDate not supplied

[Dynamics of the direction of static connections in the electrical activity of the cerebral cortex in the cat].

Data have been obtained on three cats for analysis of statistic connections of electrical activity in the visual, parietal and somatosensory cortical zones during development of evoked potentials to photic signal in these areas, and also in periods previous to photic stimulation and on traces of its action. An increase in shown of the influence of activity in the visual area on that of the somatosensory zone in post-stimulus periods and a sharp increase of two-way connections between these areas against the background of a relative equilibrium of direct and backward connections in trace periods.

Animals↗
PubMedDate not supplied

[Possible model of interaction between areas of the cat cerebral cortex].

The effect of neuronal activity of one area in the cerebral cortex on the activity of another area was studied on adult alert cats with algorhythm of estimation of dependence and backward connection. On this basis a structural-functional model was developed of interaction between the visual and somatosensory cortical areas in the periods of aftereffect of repeated photic stimulations. This algorhythm permits to determine quantitatively the weight and direction of the mutual influences of these areas as well as to calculate approximately the volumes of the cellular masses which may participate in the formation of connections between these areas. It is assumed that the model may be used as one of the numerous means of studying the complex pattern of brain structures interactions.

Animals↗