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The preservation of the effect of dynamic scanning of a part of the orientation diapason during development of neuron responses in the primary visual cortex of cat was examined after equalization of their latencies and after estimation of only highly significant fragments of their reactions. It was found that this effect was preserved in 13 neurons out of 17 examined ones: it remained invariable in 7 units of this group and was modified due to a shift of the scanning beginning along the diapason of orientations, to an increase of scanning diapason or to a change of scanning direction. The stabilization of the orientational tuning occurred only in 4 cells after equalization of latencies. The obtained results confirm that the dynamic changes of orientation tuning in the majority of visual cortex neurons are connected with reorganization of the time pattern of the reaction, as suggested by the hypothesis of the spatial-temporal orientation coding in the visual system.  相似文献   
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A study of the effect of the main risk factors of atherosclerosis in coronary patients on the prevalence of lipoidosis and prelipid changes in the aortal intima showed a week interrelationship between the studied risk factors and prevalence of lipoidosis. A noticeable significant interrelationship of the prevalence of prelipid changes in the aortal intima, patient's age, the IRI level and alpha-XC concentration in the blood plasma was established. An equation was described. A nomogram was presented permitting determination of the prevalence of prelipid changes in the aortal intima and, consequently, the phase of a course of atherosclerosis during the patient's lifetime on the basis of the above risk factors.  相似文献   
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Changes in the duration of the Achilles reflex were studied in subclinical disturbances of thyroid function. For this purpose the duration of the Achilles reflex, the levels of T4, T3, iodine protein bound TSH and cholesterol were investigated in children admitted to hospital with the general diagnosis of the "euthyroid goiter". Clinical and laboratory findings revealed subclinical types of the diffuse toxic goiter, hypothyrosis, chronic thyroiditis, endemic goiter, nodular goiter, pubertal struma and sporadic euthyroid goiter. The aim of the study was to define the diagnostic importance of reflexometry in subclinical disorders of thyroid function and to assess the relationships between metabolic derangements and the duration of the Achilles reflex. Changes in the duration were shown to correspond to disorder of thyroid function. In 76% of the cases reflexometry brought about the correct assessment of the patient's thyroid status. A significant conformity of the levels of TSH, T3, T4 to the duration of the Achilles reflex was shown.  相似文献   
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Background: Several collaborations in communicable disease surveillancehave developed between European Union member states. Involvementin these activities takes time and money. It is vital that collaborationsare established in areas most likely to be beneficial. An exercisewas undertaken to inform national surveillance centres and theEuropean Commission as to priority areas for the developmentof collaborations. Methods: A modified Delphi exercise was undertakenamongst the heads of centres with responsibilities for surveillanceat national level in the member states of the EU. Participantsdeveloped, agreed and ranked criteria for developing collaborations.A list of communicable diseases and syndromes was then rankedusing a Likert-type scale. Three rounds were undertaken. Betweenrounds, scores and a ranking were fed back showing where participantshad ranked items, compared to the overall mean and rank distribution.For the third round participants were asked to use a categoricalscale, nominating six or ten high priority disease areas. Results:Response rates were 87.5% for round 1, 44% round 2 and 87% round3. The low round 2 response rate appeared to be because respondentsdid not wish to alter their rankings. The six high priorityareas were outbreaks of gastroenteritis/food poisoning, CID/otherslow virus infections, serious imported diseases, legionellosis,antimicrobial resistance and tuberculosis. When participantsgave ten high priority areas meningococcal disease, travel advice,vaccination/immunization and influenza were also included. Thefinal lists were accepted at the meeting of participants. Conclusions:The process was successful in developing both a priority listand consensus.  相似文献   
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This study was designed to examine the effects of nisoldipine(relative to placebo), a new dihydropyridine calcium entry blockingagent, in the treatment of silent ischaemia in conventionaldoses. A total of 409 patients with proven coronary artery diseasewere screened and of this 64 had at least six episodes or atotal duration of 30 mm of ST segment depression (1 mm lastingat least 1 min) over 48 h. Fifty-two patients ultimately completeda randomized double-blind cross-over study comparing nisoldipine5 mg twice a day, nisoldipine 10 mg daily and placebo. There was a reduction in the ST segment integral and numberof episodes of ST segment depression when compared to placeboon treatment with nisoldipine 5 mg twice a day and nisoldipine10 mg daily. However, the confidence limits were wide and crossedthe no-treatment effect line. In addition, the nisoldipine dosesneither affected the circadian distribution of ischaemic episodesnor caused an alteration of the workload achieved either atpeak exercise or at 1 mm ST segment depression measured 24 hafter nidoldipine 10 mg or 12 h after nisoldipine 5 mg. We conclude that frequent silent ischaemia in patients withproven coronary artery disease is relatively uncommon, it accountsfor approximately 16% of patients with positive exercise. Inthese patients nisoldipine, given as 5mg twice a day and 10mg daily, showed no significant therapeutic effects, eitheron the frequency or severity of silent ischaemia. New formulationsof slow release nisoldipine are consequently being developedso that a fuller 24 h therapeutic profile may be obtained.  相似文献   
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In this study, the effects of interoceptive stress on the indices of free-radical oxidation and the corticosterone contents in the brain and blood of male rats were examined. In addition, we studied the effects of the GABA-like nootropic drug calcium hopanthenate and panthenol on these indices after stress. Interoceptive stress was induced by intraperitoneal injection of bacterial lipopolysaccharide and the studies were performed 24 h after injection. The derivatives of pantothenic acid substantially attenuated corticosterone accumulation in the hippocampus after interoceptive stress induced by systemic immune challenge but did not prevent a stress-induced increase in the level of substances that reacted with thiobarbituric acid in the blood of the animals.  相似文献   
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