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911.
912.
I. M. Fedotkin S. M. Konstantinov A. A. Tereshchenko 《Journal of Engineering Physics and Thermophysics》1973,24(5):589-592
On the basis of the solution to the equation of motion of a variable mass, a formula is derived for analytically calculating the critical radius of a vapor bubble in a boiling liquid during free flow of the latter.Translated from Ihzhenerno-Fizicheskii Zhurnal, Vol. 24, No. 5, pp. 831–835, May, 1973. 相似文献
913.
Over the last several years, there has been a growing awareness of a need for better integration of the liberal arts into nursing curricula. To facilitate this process, the authors describe a creative teaching strategy and offer specific suggestions for the selection and use of novels, short stories, plays, and poems to supplement the teaching of specific nursing content. 相似文献
914.
VP Kharchenko NI Rozhkova IM Frolov II Burdina MV Budanova MA Smirnov 《Canadian Metallurgical Quarterly》1997,(4):13-17
A complex methods was used to examine 39 females with the microcalcinates grouped in the breast. The diagnostic efficiency of a number of mammographic and sonographic signs was comparatively evaluated. Ultrasonography was shown to be advisable in differentially diagnosing cancer and sclerosing adenosis. A combination of mammography and sonography may establish an accurate diagnosis in 78% of cases. 相似文献
915.
Prepulse inhibition (PPI) is a form of plasticity of the startle response in which presentation of a weak stimulus immediately before an intense startling stimulus reduces the resultant startle response. Deficits in PPI, an operational measure of sensorimotor gating, are observed in schizophrenia patients and can be modeled in rats by the psychotogen phencyclidine (PCP). PCP-induced deficits in PPI in rats are resistant to dopamine and serotonin antagonists but can be antagonized by antipsychotics such as clozapine, olanzapine and Seroquel. These latter antipsychotics have antagonistic actions at several receptors, including alpha-1 and alpha-2 adrenergic, M1 muscarinic and gamma-aminobutyric acid (GABA)-A receptors. Although the direct actions of PCP are thought to be mediated by noncompetitive antagonism of N-methyl-D-aspartate sites, PCP thereby indirectly activates multiple neurotransmitter systems, including those affected by the aforementioned antipsychotics. The present studies examined the possibility that an antagonist action at a particular receptor subtype might be responsible for the interaction between PCP and the clozapine-like antipsychotics by testing whether a selective antagonist at alpha-1, alpha-2, M1 or GABA-A receptors would prevent the PCP-induced deficit in PPI in rats. Animals were pretreated with either the alpha-1 antagonist prazosin (0, 0.5, 1.0 or 2.5 mg/kg), the alpha-2 antagonist RX821002 (0, 0.2 or 0.4 mg/kg), the M1 muscarinic antagonist pirenzepine (0, 10 or 30 mg/kg) or the GABA-A antagonist pitrazepin (0, 1.0 or 3.0 mg/kg) and then treated with either saline or PCP (1.5 mg/kg). Because prazosin was effective in blocking the effects of PCP, an additional experiment tested the possibility that prazosin (0, 1.0 or 2.5 mg/kg) would block the PPI deficits produced by the dopamine agonist apomorphine (0 or 0.5 mg/kg). After drug administration, animals were tested in startle chambers. PCP was found repeatedly to decrease PPI. Prazosin (1.0 and 2.5 mg/kg) blocked this deficit in two separate experiments but did not increase base-line PPI levels. The effects on PPI were dissociable from changes in startle reactivity. Furthermore, prazosin did not antagonize apomorphine-induced disruptions of PPI, which suggests that the antagonism of the PCP effect was not simply due to a generalized improvement of deficient PPI. The antagonists for alpha-2, for M1 and for GABA-A receptors had no effect on base-line PPI or on PCP-induced disruptions in PPI. These findings indicate that the PPI-disruptive effect of PCP may be mediated in part by alpha-1 adrenergic receptors and that antagonism of alpha-1 receptors may play a major role in mediating the blockade of PCP-induced deficits in PPI by certain antipsychotics. 相似文献
916.
N Nalini K Sabitha S Chitra P Viswanathan VP Menon 《Canadian Metallurgical Quarterly》1997,35(9):964-971
Influence of coconut kernal and red chilli on the metabolism of lipids was studied in animals given 1,2-dimethylhydrazine (DMH). The average weight gain by the animals in the coconut kernal group was more than DMH and chilli treated groups. The concentration of cholesterol showed a decrease and phospholipids an increase in most of the tissues studied, of the kernal groups. The cholesterol-phospholipid ratio was found to be increased in most of the tissues of all experimental groups, when compared to control animals. HMG CoA reductase activity decreased in the high fat and most of the tissues of the kernal + DMH, kernal + chilli and kernal + chilli + DMH groups, while it increased in the DMH, chilli and chilli + DMH groups. Histopathological studies showed that coconut kernal supplemented animals had fewer papillae, lesser infiltration into the submucosa and lesser changes in the cytoplasm with decreased mitotic figures. Coconut kernal, thus reduced the mutagenic and carcinogenic effect of chilli and DMH respectively. 相似文献
917.
Biocontrol potential of Mesocyclops thermocyclopoides against first instar larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus was studied under laboratory conditions. It was found that M. thermocyclopoides had the highest predation efficacy against Ae. aegypti followed by An. stephensi and Cx. quinquefasciatus. There was a significant reduction in the predation efficacy of M. thermocyclopoides against Cx. quinquefasciatus in the presence of alternate food (p < 0.01). The cage simulation trial indicated that M. themocyclopoides has the potential to control Ae. aegypti breeding effectively in a container type of habitat. 相似文献
918.
919.
VK Litovkoa IP Zhurilo VP Kononuchenko VZ Moskalenko AM Kharagezov 《Canadian Metallurgical Quarterly》1998,(6):28-29
The experience of diagnosis and treatment of the ovarial tumor and cyst in 68 girls was summarized. Children were admitted to the hospital with an acute abdomen signs and in a planned order as well. All the patients were operated on. Children with benign ovarial tumor and cyst are alive. Four patients with malignancy have died. 相似文献
920.
VP Torchilin 《Canadian Metallurgical Quarterly》1997,41(2):141-153
The current status of application of liposomes and micelles as carriers for diagnostic imaging agents in experimental and clinical medicine is considered. Liposomes and micelles loaded with appropriate contrast agents have been shown to be suitable for all imaging modalities, including gamma-, magnetic resonance (MR), and computed tomography (CT). The methods are briefly described to prepare liposomes loaded with various contrast agents, as well as some basic data on their in vitro and in vivo properties and biodistribution. Certain pharmacokinetic considerations associated with the use of plain and long-circulating liposomes and micelles as pharmaceutical carriers are discussed. The application of contrast-loaded liposomes in different modalities for the experimental and clinical imaging of various organs, tissues, and pathological conditions is briefly reviewed. New trends in the preparation and use of contrast-loaded liposomes and micelles are also considered, such as the application of amphiphilic polychelating polymers and polymers for steric protection of microparticulate pharmaceutical carriers. 相似文献