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1.
1.  Experiments to investigate the creep phenomena of the taenia coli were performed in hypotonic (207 mosm) and hypertonic (447 or 463 mosm) media, in the relaxed (Ca2+-depletion+verapamil) as well as in the contracted (K2SO4-depolarized) state. They were compared with earlier results in isotonic media. The samples were standardized with respect to their volume (weight) before the beginning of the experiment.
2.  Neither in the relaxed, nor in the contracted state was there a statistically significant difference in mean total length observed within each test series after loading with 9928 dyn for 2000 s (about 33 min) in the different osmotic media. We define total length as unloaded initial lengthl o+initial pure elastic extensionl E+creep N.
3.  In the contracted state the mean total lengths attained by elastic extension and creep are significantly greater than in the relaxed state in both hypotonic and isotonic media. The greater variance in the data for hypertonic solutions makes any statistical decision of this kind impossible.
4.  The typical time course of creep (N) and particularly the hyperbolic dependance of N anddN/dt stated in an earlier paper could also be observed here under varied osmotic conditions.
5.  The results suggest that the viscosity of the cell plasma is not significant for the time course and extent of creep in smooth muscles of vertebrates. Creep probably takes place in the solid structures of the cells: most particularly the contractile proteins may be involved.
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2.
1.  Emotional stress arising during intensive mental arithmetic in healthy subjects causes an increase of about twice in the muscular blood flow.
2.  The emotional vasodilator response is considerably weaker in patients with muscular glycogen disease, in which the normal course of glycogenolysis is disturbed. After administration of fructose, which can be incorporated into the glycolytic cycle below the level of the metabolic block, the vasodilatation is somewhat increased.
3.  The vasodilator response during emotional stress in healthy subjects is much stronger in the mixed tibialis anterior muscle than in the red soleus. This effect may be connected with differences in the composition of the two muscles, which contain red aerobic and white anaerobic muscle fibers in different proportions.
4.  The cause of the increased blood flow in the muscles during emotional stress can be considered to be activation of glycolysis in the muscle fibers.
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3.
1.  A study has been made of the effect of serosally added sugars on the transmural potential difference and electrical resistance of the perfused goldfish intestine.
2.  Addition of glucose at the serosal side resulted in a decrease of the transmural potential difference independent of the presence or absence of glucose at the mucosal side. The transepithelial resistance did not change.
3.  The serosal glucose effect persisted in the presence of phlorizin at the mucosal side.
4.  With the actively transported non-metabolized glucose analogue 3-oxy-methyglucose the same effects were observed as with glucose.
5.  Replacement of NaCl by cholineCl, RbCl or LiCl at both sides of the intestine had a diminishing effect on the glucose evoked potentials and on the transepithelial conductance.
6.  Phlorizin in concentrations lower than 10–4 M, at the serosal side did not influence neither the mucosal nor the serosal glucose effects.
7.  Ouabain at the serosal side inhibited the serosal glucose effect and decreased the transepithelial conductance.
8.  The results support the concept that sugar transport at the serosal side of the epithelial cell has features in common with the sodium-dependent sugar transport mechanism at the mucosal side.
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4.
The effective spread of stimulating current for pyramidal tract (PT) cells and fibers was studied using a method of cancelling the shock artifacts and the following results were obtained:
1.  The excitability of PT axon collaterals was as high as that of PT cells.
2.  These axon collaterals extended as far as 1.0 mm horizontally from the PT cells.
3.  The low threshold area for activation of a given PT cell was as wide as 3–4 mm2 on the surface of the cortex.
4.  Intracortical microstimulation (ICMS) delivered to the PT cell layer produced direct (D) and indirect (I) descending volleys in the pyramidal tract, but ICMS to the superficial layer (III) produced only I-waves.
5.  These I-waves grew significantly larger after 15–20 msec from the start of the train of stimuli.
6.  It is concluded that either surface stimulation, or short train of ICMS is inadequate for delineating fine localization of motor function within the cortex. Longer train (30–40 msec) with high frequency pulses (300–400 cy/sec) can produce muscle contraction with much smaller currents, increasing the accuracy of measuring the localization of motor function.
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5.
In autoimmune haemolytic anaemia (AHA) antibody(ies) are directed at ‘self’ red blood cells (RBC) and can effect their destruction. This removal of RBC may be enhanced by the additional presence of complement on the cell membrane. The diagnosis of AHA requires the demonstration of such antibody(ies), which are able to sensitise autologous erythrocytes in vivo. AHA has been described in a variety of animal species but the techniques employed in the laboratory diagnosis have, generally, been extrapolated from those used in human serology. The application of newer and more sensitive techniques to the assessment of RBC sensitisation with antibody and complement, has improved the diagnosis of AHA. Furthermore, it is now possible to assess the significance of the degree of RBC sensitisation and to evaluate treatment regimens. Approaches to the assessment of RBC sensitisation are:
1.  Agglutination tests
a)  Broad spectrum antiglobulin reagents
b)  Monospecific reagents — anti IgG, anti IgM and anti C3
c)  Monoclonal antibodies (with subclass specificity)
2.  Enzyme-linked immunosorbent assays (ELISA)
a)  Whole RBC
b)  Isolated cell membranes
c)  Purified antigen
3.  Flow cytometry. Accurate assessment of subpopulations of RBC, with varying degrees of sensitisation. These techniques require refinement but are potentially the most sensitive.
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6.
1.  The intensity of the transformation of T into E2 and DHT in the hypothalamus of 21-day-old male rats is greater than in adults.
2.  The aromatase inhibitor ATD intensifies the formation of DHT in the hypothalamus of sexually mature male rats.
3.  The LH level of LH and T in the blood plasma increases significantly under the influence of ATD in male rats. The reaction of LH is markedly more intense in prepubertal animals as compared with sexually mature animals.
Translated from Problcmy Éndokrinologii, Vol. 36, No. 5, pp. 68–71, October–November, 1990.  相似文献   

7.
1.  The administration of a blocker of a-adrenoreceptors does not influence the blood content of LH and FSH in the early hours of the E stage.
2.  The administration of a blocker of DA (haloperidol) decreased, while a stimulator of the action (parlodel) increased the concentration of FSH in the blood at the 1 and 3 h stages of E without changes in the blood of LH.
3.  An interconnection between the decrease in the secretion of FSH and the level of nuclear E2 receptors in the adenohypophysis in the early hours of the E stage.
Translated from Problemy Éndokrinologii, Vol. 36, No. 3, pp. 53–57, May–June, 1990.  相似文献   

8.
1)  CROM reduced hypoxia-induced pulmonary vasoconstriction and maintained PaO2 with an increase in cardiac output.
2)  Low doses of CROM infused into the kidney caused pronounced renal vasodilation, marked natriuresis and a significant increase in cardiac output with minor changes in blood pressure.
In addition to its previously described systemic antihypertensive effects, CROM also reduces hypoxia-induced pulmonary hypertension and shows marked renal vasodilation with natriuresis in anaesthetized dogs.  相似文献   

9.
(1)  The isolated rabbit ear was perfused via its artery and the venous outflow superfused a PGE-sensitive rat stomach strip or a PGF-sensitive rat colon.
(2)  Injection of bradykinin intra-arterially into the ear produced a larger contraction of the rat stomach strip than the application of the same dose of bradykinin directly to the superfused muscle.
(3)  This difference is explained as a release of PGE-like material by bradykinin, since indomethacin (infused i.a. into the ear) reduced the effect of the i.a. applied bradykinin.
(4)  PGF-like material could not be detected in the venous effluent.
(5)  ACh released only minimal amounts of PGE-like substance.
(6)  Conclusion: The amount of PGE-like material released by bradykinin is large enough to sensitize the paravascular pain receptors in the rabbit ear for the attack of bradykinin. Therefore, inhibition of PG-synthesis (i.e. by indomethacin) or inhibition of the sensitizing action of E-type PGs (i.e. by polyphloretin phosphate) reduces the pain producing effect of bradykinin. Since ACh releases only minimal amounts of E-type PGs, its effect is reduced only to a minimal extent by indomethacin or polyphloretin phosphate.
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10.
1.  A decrease in the level of activity of both motivational and copulatory components of sexual behavior was observed during the development of experimental diabetes following the administration of streptozotocin to rat males.
2.  The concentration of LHRH in diabetic rats decreased in the ME [sic], and similar changes were recorded in both the PA and the MBH when it was determined in the synaptosomal fraction of the hypothalamus.
3.  The concentration of nuclear E2 receptors was increased in the APA at the level of the hypothalamus, whereas the number of testosterone-binding sites did not differ from the values of the control group.
4.  The level of LH and FSH in the blood of the rats did not change during the development of diabetes, the concentration of PRL and T decreased, and that of E2 increased.
Translated from Problemy Éndokrinologii, Vol. 38, No. 6, pp. 46–50, November–December, 1992.  相似文献   

11.
1.  The monoamine content in the various parts of the hypothalamus changes during the estrous cycle.
2.  In the course of the estrous cycle the DA concentration in the arcuate region reaches a maximum at 6 p.m. of stage D2 and falls to a minimum at 10 a.m. of stage P.
3.  The NA level in the preoptic region is raised at 6 p.m. of stage D2 and lowered at 10 a.m. of stage P.
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12.
The subjects of investigation were 13 dead thorotrast patients, 10 male, 3 female, with ages ranging from 45 to 79 years. Two thousand organ and tissue specimens were investigated by means of autopsy and by both microscopic-autoradiographic and neutron activation analysis in order to detect late effects and to determine on approximate mean concentration of 232Th (mg per g of tissue).A comparison between late effects and concentrations of the dye medium led to the following conclusions:
1.  232Th is, after intravascular injection, deposited in all organs and tissues of the human body.
2.  The highest mean concentrations are shown in the spleen, liver, bone marrow, and lymph nodes.
3.  The distribution of 232Th is inhomogeneous in all organs and tissues. The variations of maximum and minimum concentration lie around factor 2.2×100–2.4×105.
4.  Late effects occur only in spleen, liver, lymph nodes, and bone marrow, but not in organs and tissues that show a mean concentration of 232Th under 10–1 mg per g tissue.
5.  It is highly probable that tumors of thorotrast patients in organs other than spleen, liver, lymph nodes, and bone marrow are not caused by deposition of 232Th or ThO2.
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13.
AECA represent a new family of autoantibodies detectable in systemic autoimmune diseases. Different findings support their poten-tial importance both from a diagnostic and a prognostic point of view:
1.  AECA do not seem to be a mere epiphenomenon;
2.  Are not related to a polyclonal B-cell activation;
3.  React with surface endothelial antigens;
4.  Correlate with disease activity;
5.  In some cases behave as an indirect marker of in vivo endothelial damage;
6.  Correlate with disease activity; and
7.  In vitro experiments support a possible pathogenetic role in sus-taining autoimmune vasculitis.
On the other hand, AECA do not display an absolute cell specificity, being crossreactive, at least in part, with other cell types and lack of disease specificity. Up to now, AECA determination are still matter of research but their clinical usefulness in autoimmune diseases could increase when simpler assays for the detection will be available.  相似文献   

14.
1.  The immobilization of rats for 2 min with repetition after 3 min induces a significant increase in the secretion of thyroid hormones.
2.  This increase in secretion is abolished by the administration of the α-blocker prazosin 1 h before exposure.
3.  The acute stress induced by repeated immobilization increases the activity of the thyroid conversion of T4.
Translated from Problemy éndokrinologii, Vol. 39, No. 5, pp. 47–48, September–October, 1993.  相似文献   

15.
1.  The administration of thymosin (fraction 5) to mice in a dose of 1 g/mouse leads after 3 h to an increase in the level of corticosterone in the blood.
2.  The preliminary administration of a blocker of ACTH secretion, dexamethasone, suppresses the effect of thymosin on the adrenals.
3.  When tactivin was administered in doses of 0.1, 0.5, and 2.5 g/mouse, a tendency to an decrease in the level of corticosterone in the blood was found after 3 h.
4.  Tactivin dose-dependently suppresses the specific production of corticosterone in the adrenal in vitro.
Translated from Problemy Éndokrinologii, Vol. 36, No. 6, pp. 76–79, November–December, 1989.  相似文献   

16.
Conclusions  
1.  Development of experimental diabetes in male rats is associated with reductions in the blood T concentration and in the number of nuclear androgen receptors in the adenohydraphysis. Blood LH and FSH levels did not change.
2.  The LH-RH sensitivity of the hypophysis in STZ-treated male rats decreased sharply on incubation for more than 1h.
3.  Administration of STZ to female rats led to disruption of the estral cycle, accompanied by a reductions in the cyclic secretion of gonadotropins and sex hormones.
4.  The development of diabetes in cycling female rats led to a reduction in the concentration of nuclear E2 receptors in the PR and hypophysis, and the number of T-binding sites decreased only in the hypophysis.
5.  The gonadotropin wave stimulated by sex steroids in ovariectomized female rats with diabetes was significantly reduced, due to changes in the activity of the LH-RH-producing system.
Laboratory for the Physiology of the Endocrine System (Director Professor V. N. Babichev), Institute of Experimental Endocrinology (Director Academician of the Russian Academy of Medical Sciences I. G. Akmaev), Endocrinological Scientific Center (Director Academician of the Russian Academy of Medical Sciences I. I. Dedov), Moscow. Translated from Problemy éndokrinologii, Vol. 43, No. 3, pp. 43–47, May–June, 1997.  相似文献   

17.
1.  The effect of Na and K ions on active Na transport was studied in guinea-pig auricles by means of flame photometry.
2.  The Na influx into preparations rewarmed in Tyrode's solution after cooling was estimated to be about 1.05 mmole/l fibre water·min ((l.f.w.·min) or c. 8 pmole/cm2·s. Intracellular Na ions enhanced the active Na efflux over a wide range of concentrations. A decrease in the extracellular Na concentration ([Na] o ) had no major effect on the active Na efflux.
3.  Extracellular K ions initiated an active Na efflux from rewarmed auricles with an elevated [Na] i over a narrow range of K concentrations ([K] o ).
4.  Assuming Michaelis-Menten kinetics the maximal active Na efflux activated by internal Na ions was calculated to be about 4 mmole/l.f.w.·min (30 pmole/cm2·s). Half maximal Na efflux occurred at about 22 mmole/l.f.w. [Na] i . The maximal K-activated active Na efflux was deduced to be about 3.7 mmole/l.f.w.·min (28 pmole/cm2·s) and was half maximal at a [K] o of about 0.2 mM.
5.  It is tentatively concluded that the maximal active Na efflux from guinea-pig atria is 3–4 times larger than the physiological flux. Under normal conditions active Na efflux in heart is mainly regulated by variations of [Na] i .
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18.
1.  Administration of insulin does not significantly affect the level of SEBP in the livers of male rats.
2.  Adrenalectomy and administration of dexamethasone do not cause any pronounced changes in the sexual differentiation of the SEBP content in the liver.
3.  Administration of physiological doses of T3 produces a dose-dependent and reversible decrease in the level of SEBP in the livers of sexually mature male rats, and also decreases the degree of induction of this protein by androgens in the livers of females.
4.  The action of T3 does not significantly depend on the sex hormones and pituitary factors.
5.  Administration of STH raises the level of SEBP in the liver only in hypophysectomized males but not in intact or castrated males.
Translated from Problemy Éndokrinologii, Vol. 35, No. 3, pp. 59–63, May–June, 1989.  相似文献   

19.
1.  Single units in the III. and VI. nerve nuclei were continuously recorded together with vestibular stimuli and eye movements in macaques before, during, and after administration of barbiturate.
2.  The visual input was functionally detached from the oculomotor system during the deeper stages of anesthesia, whereas some kind of vestibulo-ocular response could always be elicited.
3.  The finding of various phase values between the maximum impulse rate IRmax of oculomotor units and the maximum stimulus velocityv max during 1 Hz sinusoidal vestibular stimulation ranging from about 65 deg phase lead to 65 deg phase lag is suggested as important for the explanation of the phase shifts between head rotation and eye movement during anesthesia.
4.  The phase relationship between IRmax andv max was found to be unchanged, whereas the characteristic of IRmax versusv max was highly sensitive to arousal stimuli for some oculomotor neurons. This sensitivity was represented exclusively by activation rather than inhibition.
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20.
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