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21.
AB Jamjoom NF Khalaf AA Mohammed ZA Jamjoom TY Kashoggi OB Abdelbasit NU Rahman 《Canadian Metallurgical Quarterly》1998,140(11):1121-1125
In this study, the authors attempt to provide an account of the factors that affect the outcome of hydrocephaly in 26 foetuses. The hydrocephalus was related to a myelomeningocele in 35% of patients. Sixty-two percent of foetuses showed intra-uterine progression of their hydrocephalus and 50% were shunted postnatally. At a mean follow up of 2 years, the outcome was considered "fair" in 54% of patients. Our findings demonstrate that in foetal hydrocephaly a more favourable outcome is expected in patients with hydrocephalus which does not progress in utero, in whom the labour is not induced before 36 weeks of gestation, who are delivered vaginally weighing more than 2.5 kg and have a head circumference below the 95th centile and a CT cortical mantle thickness of 2 cm and more and who are treated by CSF shunting. The diagnosis of the foetal hydrocephaly at or before 28 weeks of gestation and the presence of a myelomeningocele did not affect the outcome significantly. Neurosurgeons are reminded to keep an open mind for infants with foetal hydrocephaly and to offer active treatment to patients with a potentially favourable outcome. 相似文献
22.
VP Barkhatova ZA Suslina VG Ionova IA Chudakova OE Mel''kina MM Tanashian OIu Rebrova 《Canadian Metallurgical Quarterly》1998,98(8):34-38
Contents of lipids (cholesterol CS, triglycerides) as well as levels of CS of lipoproteins of different density and of apolipoproteins A1 and B were measured in blood serum of 31 patients in different periods after of ischemic stroke. The majority of the indices studied were significantly decreased in men in acute periods of the stroke, especially in 8-21 days after the stroke development. Meanwhile, the levels of lipids, CS lipoproteins of both low and very low densities were increased later. Contents of CS of antiatherogenic lipoproteins of high density (HDLP) was low in different periods after the development of disorders of cerebral circulation. This confirms the concept that low level of HDLP is one of the risk factors of ischemic stroke. Decrease of the levels of both lipids and CS of lipoproteins of different density was more pronounced in patients with more severe atherosclerotic damages of the main cerebral arteries. Disorders of metabolism of lipoproteins in ischemic disorders of cerebral circulation are discussed with reference to literary data taking into consideration their heterogeneity. Genetically determined pathology of certain apolipoproteins plays a key role factor in the development of early atherosclerosis and in the elucidation of biochemical markers of the primary damages of cerebral vessels. 相似文献
23.
The test with running on a treadbane showed a 56% increase of working capacity in the control group of male albino mice on the 20th day of training. Oral administration of elton, leveton, phytoton, and adapton, as well as Leuzea and Rhodiola extracts and Schisandra chinensis tincture caused a statistically significant increase in the time of running on the treadbane of animals by the 10th day of medication. The increase in the working capacity of the animals was more marked by the 20th day. In the test of swimming "to the limit" adapton, phytoton, leveton, and elton increased to a greater extent the working capacity of male albino rats in diminishing succession (from 213 to 168%). Schisandra tincture and Rhodiola and Leuzea extracts also increased the swimming time of the animals by 135-159%. 相似文献
24.
DL Kraitchman AA Young DC Bloomgarden ZA Fayad L Dougherty VA Ferrari RC Boston L Axel 《Canadian Metallurgical Quarterly》1998,40(2):311-326
A single integrated examination using regional measurements of perfusion from contrast-enhanced MRI and three-dimensional (3D) strain from tissue-tagged MRI was developed to differentiate infarcted myocardium from adjacent tissue with functional abnormalities. Ten dogs were studied at baseline and 10 days after a 2-hour occlusion of the left anterior descending coronary artery (LAD). Strain was determined using a 3D finite element model. Two-dimensional measurements of hypoenhancing regions were highly correlated with myocardial viability (r = 0.96). Signal intensity versus time curves obtained from contrast-enhanced MRI were used for quantitative perfusion analysis. The remote and adjacent noninfarcted tissue of the dogs with LAD occlusion, as well as the infarcted tissue, exhibited abnormal deformation patterns as compared to normal dogs (positive predictive value (PPV) of strain determination of infarction = 66%). Integration of contrast-enhanced MRI results with 3D strain analysis enabled the delineation of the myocardial infarction (PPV = 100%) from functionally compromised myocardium. This integrated cardiac examination shows promise for noninvasive serial assessment of potentially jeopardized noninfarcted myocardium to study the process of infarct remodeling and expansion. 相似文献
25.
Schistosoma mansoni and S. japonicum infections in nude mice (nu/nu) were compared with infections in nu/+ heterozygotes or intact mice. Seven to 12 weeks after exposure to S. mansoni, the responses of Swiss NCR, C3H, BALB/c and C57B1/6 nude mice did not differ substantially. Nude mice of all these strains showed minute granulomas around eggs in the liver and minimal hepatic fibrosis. Microvesicular and necrotizing changes in hepatocytes were similar in all mouse strains, and S. mansoni infections were frequently lethal to nude, but not to intact mice between the seventh and ninth weeks of infection. Nude mice that survived the ninth week of infection generally lived until the 12th week. The number of eggs per mature worm pair in the tissues of S. mansoni-infected nude mice was similar to the number in intact mice, but nude mice passed fewer eggs in the feces. Nude mice that received serum from infected intact mice excreted eggs in the stool in numbers equivalent to intact mice, but continued to form minute granulomas around S. mansoni eggs. Reconstitution with fetal thymus or with splenocytes from normal or S. mansoni-infected mice partially or completely restored hepatic granuloma size, granuloma eosinophils, hepatic fibrosis, and excretion of eggs in the feces. In contrast to S. mansoni infection, S. japonicum infections in nude mice did not cause necrosis of hepatocytes or excessive mortality, and S. japonicum eggs were passed in the feces in numbers equivalent to those passed by infected intact mice. 相似文献
26.
1. Microdialysis of the frontal cortex of freely-moving rats and uptake of [3H]noradrenaline into cortical synaptosomes were used to evaluate changes in efflux of noradrenaline in vivo and uptake of [3H]noradrenaline in vitro, respectively, induced by the selective serotonin reuptake inhibitors (SSRIs), fluoxetine and citalopram, and the tricyclic antidepressant, desipramine. 2. Noradrenaline efflux was increased during local infusion into the cortex of each of these drugs. All three agents also inhibited synaptosomal uptake of [3H]noradrenaline; this inhibition was unaffected by a substantial (50%) lesion of central 5-hydroxytrytaminergic neurones induced by intracerebroventricular infusion of 5,7-DHT (150 microg). 3. A noradrenergic lesion (70%), induced by pretreatment with the selective neurotoxin, N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4, 40 mg kg(-1) i.p.), 5 days earlier, abolished the increase in noradrenaline efflux caused by local infusion of fluoxetine. In contrast, the desipramine-induced increase in efflux was greater than in non-lesioned rats whereas the effect of citalopram on noradrenaline efflux was unaffected by DSP-4 pretreatment. 4. The combined results of all these experiments suggest that there could be more than one, functionally distinct, noradrenaline uptake site in rat frontal cortex which can be distinguished by their different sensitivities to desipramine and the SSRIs, fluoxetine and citalopram. 相似文献
27.
Six hooded crows (Corvus cornix) were trained in alternative simultaneous matching-to-sample and oddity-from-sample tasks with visual stimuli. Bird's ability to acquire the abstract same/different concept was investigated. For this purpose three stimulus sets of the following categories were used: color (black and white cards), shape (Arabic numerals "1" and "2"), and numerousness (heterogeneous arrays of 1 or 2 elements). These three sets were used for training successively and repeatedly; each time the stimulus set was changed for the next one after the criterion (80% correct or better over 30 successive trials) was reached with the previous one. The training procedure was repeated until the criterion could be reached for each of the three stimulus sets within the initial 30-50 trials. After that, the abstractness of the rule acquired by birds was tested. First, the "partial" transfer tests were conducted, which consisted in presentation of novel stimuli with familiar ones (numerals and arrays in the range from 1 to 4). At the final stage, only sets of novel numerals and arrays in the range from 5 to 8 were presented. The crows demonstrated successful transfer in all of these tests, including the test with absolutely novel stimuli (in the first 24 presentations: min 75.0%, p < 0.02; max 83.3%, p < 0.01). The level of correct choices did not differ from the baseline (p > 0.05). This allows us to conclude that birds are capable for formation of the abstract same/different concept. 相似文献
28.
R Goyal ZA Syed PS Mukhopadhyay J Souza A Zivin BP Knight KC Man SA Strickberger F Morady 《Canadian Metallurgical Quarterly》1998,9(3):269-280
1. (5R)-3-[2-((1S)-3-cyano-1-hydroxypropyl)benzothiazol-6-yl]-5-metho xymethyl-2-oxazolidinone (E2011) has two chiral centers in its structure. In vivo optical inversion of the hydroxy group at one of the chiral centers converts E2011 to a diastereoisomer (ER-20593). Pharmacokinetic parameters of E2011 and ER-20593 were determined after administration of E2011 to rat at 10 mg/kg, and the plasma concentration ratios of E2011 to ER-20593 were almost constant after Tmax of the plasma concentrations. 2. E2011 and ER-20593 were separately administered orally to six species in addition to rat, and the species differences in both directions of epimerization (i.e. from E2011 to ER-20593 and from ER-20593 to E2011) were studied by measuring the plasma concentrations of both compounds. In mouse, guinea pig, dog, and squirrel monkey, the epimerization of E2011 to ER-20593 did not occur, but the epimerization of ER-20593 to E2011 did. In rat, pig and rhesus monkey, the inversion of E2011 to ER-20593 occurred, but the ratios of this inversion were smaller than those for the inversion in the opposite direction. E2011 underwent about 15% inversion to ER-20593 in rat, which was the largest inversion in the seven species examined. 3. To study the mechanism of the epimerization, deuterium-labelled E2011 and ER-20593 (created by substituting the proton at the chiral center of the parent compounds for deuterium) were orally administered (separately) to rat and dog, and the concentration ratios and molecular weights of E2011 and ER-20593 in the plasma were determined by hplc and FAB(+)-mass spectrometry respectively. The results indicated that the major mechanism of the epimerization was oxidation to the carbonyl form followed by reduction to the original epimer and/or the other epimer. 4. The carbonyl form of E2011 (CO-E2011) was reduced to E2011 and ER-20593 (alcohol forms) by liver cytosol and microsomes from rat and dog in vitro with NADH or NADPH. The resultant epimeric ratios (E2011:ER-20593) were consistent with the in vivo results in rat and dog. 5. In conclusion, species differences in the epimerization of E2011 would result from product stereoselectivity of the reductase activity with the carbonyl intermediate. 相似文献
29.
MI Kostenetski? GT Gribinenko LS Kravtsova GL Ryzhova ZA Khripko 《Canadian Metallurgical Quarterly》1998,94(3):26-28
Central and cerebral hemodynamics was studied using echocardiography and transcranial dopplerography in 200 poststroke patients over 60 in the course of 5-year follow-up. It was established that cardiac hypodynamic syndrome, i.e. continuous or paroxysmal fall of minute blood volume below 3 l, is the most significant contributing factor in the onset of cerebral ischemia. Drugs are recommended for prevention of ischemic stroke. Those lowering cardiac hemodynamic reserve should be excluded in patients at high risk of acute failure of cerebral circulation. 相似文献
30.