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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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ABSTRACT: A Male rabbit was immunized with rat testicular cytochrome (Cyt) ct and mated with normal, unimmunized females. The matings resulted in abnormal pregnancies: no offspring or stillborn or undersized liveborn offspring weighing 25–30 gm each. Another unusual observation was that fur-pulling behavior, normally exhibited by pregnant female rabbits at the end of the gestational period, was absent in all of these pregnancies. Therefore, immunization of a normal rabbit with testicular cyt ct appeared to interfere with physiological and behavioral aspects of pregnancy in normal female rabbits. The immunological basis of these findings remains to be determined.  相似文献   
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We determined the distribution of DR4 subtypes in 309 DQB1*0302-positive haplotypes found in insulin-dependent diabetes mellitus (IDDM) patients and 70 control haplotypes present only in healthy family members. An increased frequency of DRB1*0401 allele (74.4% vs. 55.7%, P = 0.003) and a decrease of DRB1*0404 allele (23.6% vs. 40.0%, P = 0.0064) was revealed. A further analysis of extended haplotypes demonstrated strong linkages between various B alleles and DRB1*04 subtypes. HLA-B39 was more frequent in DRB1*0404–DQB1*0302-positive IDDM haplotypes compared with control ones (37.0% vs. 14.3%, P = 0.049), suggesting an involvement of the region telomeric to HLA-DRB1 in the susceptibility to IDDM.  相似文献   
6.
The recently observed selective sensitivity to cross-shaped and angular figures was studied in 85 primary visual cortex (field 17) neurons in cats before and after local blockade of GABAA ergic inhibition by microiontophoretic application of the GABA antagonist bicuculline. Two opposite effects were seen: half of the neurons studied showed decreases or complete loss of sensitivity to crosses, and a third of the cells showed increases or the appearance of sensitivity to crosses. These data provide evidence for significant roles for intracortical inhibition in providing sensitivity to crosses and intersecting lines in two types of visual cortex neurons, the effects on these two types of neuron being opposite. Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti, Vol. 49, No. 2, pp. 271–278, March–April, 1999.  相似文献   
7.
Acute experiments on immobilized cats were carried out to check the suggestion that a special class of neurons ("timers") which do not change time properties of responses with variations in light bar orientation exists in the visual cortex. Previously neurons of the visual cortex with a dynamic shift of preferable orientation ("scanners") were revealed. Among 76 neurons 27 (36%) showed different properties: stability of latencies in the orientation range, shorter initial and peak latencies, duration and time of the discharge frequency increase, wider orientational tuning and worse relations between magnitudes of responses to preferred and nonpreferred stimuli. They were considered as representatives of the suggested "timers".  相似文献   
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目的:研究国产美罗培南用于抗感染治疗的临床疗效和安全性.方法:将30例中、重度急性细菌性感染患者按随机对照平行法分成2组,治疗组14例,给予美罗培南0.5g,q8h,静脉滴注;对照组16例,给予泰能(亚胺培南/西司他丁)1.0g,q8h,静脉滴注.两药疗程均为7~10d.结果:两组的临床痊愈率均为50%;临床有效率治疗组和对照组分别为85.7%和87.5%;细菌清除率分别为84.6%和85.7%;不良反应发生率分别为14.3%和18.8%.以上指标两组差异均无显著性(P>0.05).结论:国产新药美罗培南用于抗感染治疗安全有效.  相似文献   
9.
The aim of this trial was to compare the efficacy of combinationantithrombotic therapy with a prostacyclin-sparing aspirin plusanticoagulation versus conventional aspirin plus anticoagulation,when added to antianginal therapy, in patients with unstableangina or non-Q wave myocardial infarction already being treatedwith aspirin. In a double-blind (for the aspirin) study, 144prior aspirin users were randomized; 72 patients received controiled-release,prostacyclin-sparing aspirin 75 mg daily plus anticoagulation(intravenous heparin followed by warfarin to maintain the internationalnormalized ratio at 2–3), and 72 patients received conventionalaspirin 75 mg daily plus the same anticoagulation. Controlled-releaseaspirin was formulated to preserve endothelial cell prostacyclinsynthesis. Trial therapy was begun by 13.2 ± 12.3 h ofqualifying pain, and continued for 12 weeks. The frequency of recurrent angina with electrocardiographicchanges, myocardial infarction, or death, was analysed by intentionto treat. At 12 weeks, events were  相似文献   
10.
目的:探讨肺隔离症的手术治疗方法和效果。方法回顾性分析该院在2003年3月-2014年3月间收治的17例肺隔离症患者的临床资料。结果①该组17例患者中,术前确诊者13例;术中确诊4例;②采用肺叶切除术对患者进行治疗,全部痊愈,无1例死亡;③术后并发症的发生率为17.64豫(3/17),经对症处理后均缓解;④术后随访6个月~10年,复查X线胸片和CT,结果显示均正常。结论肺隔离症是临床中比较少见的肺先天性畸形,临床表现无特异性,易发生误诊和漏诊,临床中以肺叶切除术治疗为主,效果良好,值得临床推广。  相似文献   
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