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991.
We report a case of left iliofemoral vein thrombosis with extension to the inferior vena cava associated with giant right hydronephrosis secondary to ureteropelvic junction obstruction. Surgery revealed marked infrarenal vena caval compression and deviation to the left side caused by the dilated right renal pelvis, with resultant kinking of the origin of the left iliac vein. It is postulated that the reduction in blood flow caused by this compression and distortion predisposed this patient to venous thrombosis. 相似文献
992.
A Brci? 《Hand Clinics》1990,6(2):211-219
The article describes the correct technique of primary tangential excision in deep dermal and third-degree hand burns. The operation performed under tourniquet facilitates the preservation of viable tissue, which is of utmost importance in hand burns. The therapeutic results depend on the extent of destroyed tissue. Primary tangential excision prevents fibrosis due to prolonged infection and impaired circulation, thus creating much more favorable conditions for reconstruction and rehabilitation. 相似文献
993.
(i) The characteristics of the major human hepatic isoenzymes of aldehyde dehydrogenase (ALDH), ALDH I and ALDH II, were compared with the ALDH activities found in human placenta and erythrocytes, (ii) In human liver biopsies, the Km of ALDH I was approximately 7 mumol/L whereas it was 32 mumol/L for ALDH II. The Vmax for ALDH I was 2-3 times greater than the ALDH II Vmax. Human liver ALDH I and II also differed in their sensitivity in inhibitors. Namely, ALDH I was less sensitive to disulfiram than the ALDH II isoenzyme. (iii) ALDH activity in human placenta and erythrocytes was much lower than in liver tissue. Kinetic data showed that placental ALDH isoenzyme had a high Km (in the millimolar range) and increased its activity raising the pH from 7.4 to 8.8, more than the hepatic ALDH I and ALDH II isoenzymes did. Erythrocyte ALDH activity presented a dual component; the smaller one was characterized by a low Km (micromolar range), whereas most of the ALDH activity showed a high Km (millimolar range). (iv) Placental ALDH was resistant to nitrefazole inhibition and was inhibited by disulfiram in a manner similar to the hepatic ALDH I isoenzyme; erythrocyte ALDH was more sensitive to the inhibitory action of disulfiram and nitrefazole. (v) It is concluded that erythrocyte and placental ALDH isoenzymes are different from the hepatic ALDH I and ALDH II forms. It is also suggested that placental and erythrocyte ALDH isoenzymes are different high-Km isoenzymes. 相似文献
994.
R J Aitken 《British medical bulletin》1990,46(3):654-674
Our understanding of the causes of male infertility and our ability to develop an appropriate range of diagnostic tests are both dependent upon a knowledge of the cellular mechanisms responsible for the regulation of human sperm function. This review examines the intra- and extracellular factors regulating four separate components of human sperm function: sperm transport, sperm-egg recognition, the acrosome reaction and sperm-oocyte fusion. Within each of these areas the fundamental nature of the process, the control mechanisms involved, the availability of appropriate diagnostic tests and the relationship with human infertility have been considered. 相似文献
995.
996.
Kappa-opioid-receptor agonists modulate the renal excretion of water and electrolytes in anaesthetized rats. 总被引:1,自引:0,他引:1 下载免费PDF全文
1. Subcutaneous injection of the kappa-opioid agonists U50,488 (10 mg kg-1) and tifluadom (3.5 mg kg-1) into Inactin-anaesthetized, saline-infused rats was associated with a diuresis, antinatriuresis and antikaliuresis which lasted for up to 2 h. A high (5 mg kg-1), but not low (0.1 mg kg-1), dose of naloxone blocked the renal effects of U50,488. 2. U50,488 administration in anaesthetized, vasopressin-deficient Brattleboro DI rats was associated with an attenuated diuresis, though the antinatriuretic response remained intact. 3. The diuretic action of U50,488 was associated with an increase in glomerular filtration rate while fractional fluid reabsorption remained steady. In contrast, fractional sodium and potassium reabsorption were increased. 4. These data suggest that kappa-opioid agonists alter renal handling of both water and electrolytes. This appears to be mediated by two separate mechanisms: increased fluid loss largely reflects altered glomerular events while the fall in electrolyte excretion results from altered tubular handling. 相似文献
997.
Mycenon, a new metabolite from a Mycena species TA 87202 (basidiomycetes) as an inhibitor of isocitrate lyase 总被引:1,自引:0,他引:1
Mycenon (C11H5Cl3O3), a new inhibitor of isocitrate lyase (EC 4.1.3.1) was isolated from the culture broth of a basidiomycete, Mycena sp. Mycenon is a novel chlorinated benzoquinone derivative which is also active against bacteria and fungi. Malate synthase (EC 4.1.3.2) the second key enzyme of the glyoxylate cycle was not affected by mycenon. Isocitrate lyase preparations from plants, bacteria and fungi were sensitive. The following Ki-values for mycenon have been determined: Ricinus communis, 5.2 microM; Acinetobacter calcoaceticus, 11 microM; Neurospora crassa, 7.4 microM. The structure of mycenon has been determined by a single crystal X-ray analysis. 相似文献
998.
G Durrieu P Valet M Berlan A Villeneuve J L Montastruc 《European journal of pharmacology》1990,182(3):597-601
Treatment of dogs for 21 days with oral levodopa (100 mg b.i.d.) plus benserazide (25 mg b.i.d.) induced a significant increase in the number of platelet alpha 2-adrenoceptors labelled by [3H] yohimbine with no change in Kd. The rise was maximal at the end of the treatment and remained significant during the month following the cessation of treatment. Plasma catecholamine levels did not vary. Competition experiments showed a low affinity of both dopamine and levodopa for platelet alpha 2-adrenoceptors. These results suggest that levodopa treatment regulates alpha 2-adrenoceptor number in dog platelets. 相似文献
999.
The effect of thymosin fraction 5 and its synthetic component thymosin-alpha 1 administered i. p. and i. c. v. on the behavior of 219 Wistar rats in the open field was studied to establish the effective dose and time of action of both substances. It was shown that at i. c. v. administration of both compounds in a dose of 10 ng the motor activity was suppressed for about 0.5 hour. At i. p. administration thymosin fraction 5 in doses of 0.15, 0.3 and 0.6 mg/kg suppressed the motor activity for more than 2 hours. The higher the dose, the greater the degree of suppression of the motor activity. Both peptides influence in a similar way the motor activity of the animals irrespective of the route of administration. 相似文献
1000.