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71.
A small cavicorn, Gazella (Procapra) gutturosa Gmelin, 1760, is described from the Nalaikha locality (Mongolia) and assigned to the Upper Villafranchian based on the age of the Nalaikha mammal fauna.  相似文献   
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Investigation of a possibility of long-term storage of frozen (-196 degrees C) viable neurons and nervous tissue is one of the central present day problems. In this study ultrastructural changes in neurons of frozen-thawed snail brain were examined as a function of time. We studied the influence of cryopreservation, cryoprotectant (Me2SO), cooling to 4-6 degrees C, and a prolonged incubation in physiological solution at 4-6 degrees C on dictyosomes of Golgi apparatus, endoplasmic reticulum (ER) cisternae and mitochondria. It has been found that responses of these intracellular structures of cryopreserved neurons to the above influences are similar: dissociation of Golgi dictyosomes, swelling of endoplasmic reticulum cisternae and mitochondrial cristae. Both freezing-thawing and cryoprotectant were seen to cause an increase in the number of lysosomes, liposomes, myelin-like structures, and to form large vacuoles. The structural changes in molluscan neurons caused by cryopreservation with Me2SO (2 M) were reversible.  相似文献   
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Comparative efficacy of moxifloxacin and ciprofloxacin as prophylactics of infection in cancer patients with severe neutropenia after the chemotherapy was studied. The study included 40 patients with malignant lymphomas and solid tumore who received 52 courses of the aggressive chemotherapy. Twenty four patients (30 courses) received oral moxifloxacin in a dose of 400 mg once a day from the first day of the neutrophil count decrease below 1.0 x 10(9)/l until its recovery to > 1.0 x 10(9)/l or when the signs of infection appeared. In the control group 16 patients (22 courses) received oral ciprofloxacin in a dose of 500 mg twice a day. The patients in both the groups were compatible by the diagnosis, age and neutropenia duration. The median of the days of the febrile neutropenia duration in the patients prophylactically treated with moxifloxacin was statistically lower (2.1 vs 3.6 in the control group, p < 0.05). The incidence of febrile neutropenia in the moxifloxacin group was significantly lower than that in the control group (73 and 100% respectively, p = 0.01). The incidence of bacteriologically confirmed infection in the moxifloxacin group was also lower (6% vs 27.2%, p = 0.04). Therefore, moxifloxacin proved to be a more efficient agent vs ciprofloxacin (standard prophylactic) in prevention of febrile neutropenia and neutropenic infection in cancer patients, which is likely due to its higher activity against grampositive organisms.  相似文献   
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Study of parameters of the cardiac, respiratory, and motor activity (MA) was carried out on newborn rat pups for the first day after birth (P0) and at the 14th day of postnatal development (P14) after change of the activity levels of dopaminergic and noradrenergic systems. To provide an excessive level of catecholamines, the animals were administered individually with L-DOPA (25–100 mg/kg) and with the indirect adrenomimetic isoamine (3 and 10 mg/kg). Additionally there were studied effects of L-DOPA and isoamine after blockade of D1 and D2 dopamine receptors (antagonists SCH-23390 and sulpirid). The L-DOPA administration produced a dose-dependent MA enhancement with its subsequent possible conversion into the continuous generalized activity. At P0 the release of monoamines was accompanied by development of weak bradycardia. There was noted a tendency for acceleration of respiration at administration of the low dose both of L-DOPA and of isoamine and for its deceleration at high doses. At P14 the L-DOPA administration was accompanied by deceleration of the heart rate (HR) by 8% and by acceleration of respiration rate (RR) by 26%. The isoamine administration produced an insignificant decrease of HR and an increase of RR by 8% at the low dose and by 21% at the high dose of the agent. At the blockade of D1 receptors, RR remained close to the background values, while at the blockade of D2 receptors it decreased insignificantly. Blockade of D1 and D2 receptors did not cause significant HR changes. Analysis of the HR variability has shown that both after L-DOPA administration and at blockade of dopamine receptors no unidirectional reaction was observed: in 80% of rat pups the portion of nerve mechanisms of HR regulation increased, while in the rest-of sympathetic and humoral factors at a decrease of parasympathetic effects. In all rat pups the isoamine administration was accompanied by a shift of the specter power into the higher frequency area; in 60% of the animals there were enhanced sympathetic effects. At P14 in rat pups after administration both of L-DOPA and of isoamine, the sympathetic nervous effects were predominant. Thus, at P0 both at release of endogenous catecholamines and at their excessive concentration in rat pups there occurs a qualitative change of character of the catecholaminergic effects on functional activity of excitable structures, particularly of those connected with regulation of respiration.  相似文献   
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The influence of prolonged electrical stimulation of rabbit hypothalamus on blood lipids and the development of atherosclerosis were studied. The negative emotional state observed during the electrical stimulation was accompanied by blood hyperlipemia and atherosclerosis development in 1/3 noncastrated and 2/3 castrated animals.  相似文献   
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