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31.
作者以1%乙酸冲洗SD大鼠子宫内膜,获得子宫内膜酸溶性提取物。利用琼脂糖弥散法和电泳凝胶琼脂糖弥散法抗菌试验发现,子宫内膜提取物有三条主蛋白带对致病性大肠杆菌ML-35P耐药株有强抗菌活性,这三条抗菌蛋白带命名为RatUP-1,RatUP-2和RatUP-3,分别占子宫内膜提取物总蛋白量的4.5%,5.7%和6.6%。虽然提取物存在溶菌的活性,但其含量甚微,在AU一PAGE图谱上亦未能显现溶菌酶条带。本实验的结果提示子宫内膜合成一类抗菌多肽,可能在子宫抗菌机制中发挥重要作用。 相似文献
32.
将Wistar大鼠随机分成氧化胆固醇组(Och)、纯胆固醇组(Pch)和对照组,分别用氧化胆固醇混合物(250mg/kg bw/d)、纯胆固醇(250mg/kg bw/d)以及悬浮固醇用的明胶液体给大鼠灌胃,连续二天。于第二次灌胃后18小时,从大鼠尾静脉注射伊文思兰溶液,并于注射后2小时处死;取出主动脉用荧光显微分光光度术测定主动脉内膜的通透性。此外,另一部分动物在第二次灌胃后24小时处死,取出主动脉作扫描电镜的内膜观察。结果表明,Och大鼠主动脉内膜的通透性显著高于Pch组与对照组大鼠(P<0.01),而Pch组大鼠主动脉内膜的通透性和对照组无显著差异(P>0.05)。 相似文献
33.
"Chronic painter''s syndrome". A reanalysis of psychological test data in a group of diagnosed cases, based on comparisons with matched controls 总被引:4,自引:0,他引:4
Twenty solvent-exposed workers, most of them painters, had been diagnosed as cases of toxic encephalopathy in 1978/79. Two years later they were re-examined with an extensive battery of neuropsychological tests. Their performance was unchanged on retesting. We have now compared their test results with those of non-exposed control subjects. Previous impressions of significant intellectual impairment in the solvent-exposed patients could not be confirmed when the influence of age, education, and intelligence was taken into consideration. The present group with presumed toxic encephalopathy is assumed to be representative of other patients who were similarly diagnosed in our department. The presently reanalyzed cases had been diagnosed as brain damaged and reported as such in the literature. Thus, they may have contributed to the formation of the concept of the "chronic painters' syndrome" with dementia. 相似文献
34.
Mechanical or thermal injury to one of a pair of parabiotic rats with a crossed circulation but separate innervation was followed by the development of a state resembling shock in the other partner. Microcirculatory changes characteristic of either traumatic or burn shock developed in its mesentery under these circumstances. The results are interpreted as evidence in support of a humoral rather than a nervous mechanism of the microcirculatory disturbances in these types of shock.Laboratory of Pathophysiology of Extremal States, Research Institute of General Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 10, pp. 416–418, October, 1978. 相似文献
35.
Finegold I 《Clinical reviews in allergy & immunology》2004,27(2):75-82
Recent results of allergen immunotherapy research have continued to validate efficacy and have also demonstrated a truly preventive
aspect for this treatment. This review summarizes the basic principles of effective allergen immunotherapy and highlights
some of the advances that have been published in the past year. These studies show that allergen immunotherapy, when done
appropriately and properly, not only causes a decrease in symptoms and use of medication as well as an improved quality of
life, but that the progression of disease from allergic rhinitis to asthma is substantially decreased and the development
of new allergies is diminished. In addition, laboratory studies continue to demonstrate significant changes in the immune
system with a shift in the immune pathway from TH2 toward a TH1 response. The impact of anti-IgE as a therapeutic agent with allergen immunotherapy is also be reviewed. 相似文献
36.
S. P. Perrett 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,121(2):115-124
Little is known about mechanisms used by the nervous system to encode time. In light of recent evidence, cerebellar cortex
involvement in the learned timing of conditioned eyelid responses shows promise as an area of investigation into neural timing
mechanisms. Lesion studies indicate that the cerebellar cortex is necessary for response timing, but do not rule out the possibility
that response timing is encoded afferent to the cerebellum. To differentiate between precerebellar and cerebellar cortical
timing mechanisms, rabbits were trained by pairing direct stimulation of mossy fibers in the cerebellum as the conditioned
stimulus (CS) with an eyeshock unconditioned stimulus (US). We find that individual animals can produce diffently timed conditioned
responses when trained with a mossy fiber CS that has been paired with the US at various interstimulus intervals. The fact
that differently timed responses can be conditioned using constant-frequency stimulation of an invariant subset of mossy fibers
as the CS suggests that timing information in the afferent input to the cerebellum is not essential. Two rabbits trained with
single-pulse stimulation in the cerebellum as the CS also learned differently timed conditioned responses; suggesting that
fiber recruitment during a stimulus train does not convey the necessary temporal coding to the cerebellar cortex. Together
with the lesion data, these findings suggest that the learned timing of conditioned eyelid responses occurs in the cerebellar
cortex.
Received: 25 August 1997 / Accepted: 12 January 1998 相似文献
37.
Left and right, palmar and dorsal skin conductance levels (SCLs) were obtained from hospital controls, left hemisphere lesion Ss, right hemisphere lesion Ss, and diffuse or bilateral lesion Ss during several experimental conditions involving rest, passive auditory stimulation, motor reactions, and simple “perception”. The unilateral lesion groups generally displayed significantly higher palmar SCLs on the side contralateral to their lesion. Such “laterality” was not demonstrated in dorsal recordings or in the hospital controls or diffuse lesion group. These unilateral lesion groups had higher palmar SCLs during passive stimulation than during rest, motor, or perception phases. Results were discussed in terms of possible neural mechanisms underlying the phenomena. 相似文献
38.
Extraembryonic rhythmic motor activity in higher vertebrates, along with the intrinsic motor activity of the embryo, is important
for the normal development of the embryo. This can have different natures in different classes of amniotes (i.e., motor activities
of the amnion, yolk sac, and uterus), but these have similar functional importance. This activity changes reproducibly during
the process of embryogenesis, providing the optimum conditions for normal embryo development. During embryogenesis, a system
for controlling extraembryonic rhythmic motor activity is also formed. There is a trend for the regulation of this activity
to become more complex in mammals as compared with birds. Reptiles have received little study from this point of view. In
addition to regular changes in extraembryonic rhythmic motor activity during embryogenesis which depend on the developmental
stage of the embryo, motor activity can also change in response to changes in a number of environmental factors (for example,
temperature and the gas composition of the air). This demonstrates the possible involvement of embryo-associated extraembryonic
motor activity in adapting the embryo to changing environmental conditions and maintaining homeostasis for the development
of the embryo itself.
Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 84, No. 10, pp. 961–968, October, 1998. 相似文献
39.
Production of tumour necrosis factors by human T cells stimulated by a superantigen,toxic shock syndrome toxin-1
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H. AKATSUKA K. IMANISHI K. INADA H. YAMASHITA M. YOSHIDA T. UCHIYAMA 《Clinical and experimental immunology》1994,96(3):422-426
The capacity of human T cell subsets, CD4+ or CD8+ T cells, to produce tumour necrosis factors (TNF-α and TNF-β) upon stimulation with toxic shock syndrome toxin-l (TSST-I) and the requirement for MHC ctass II molecules on accessory cells (AC) in the response were investigated. The capacity of CD4+ T cells was much higher than that of CD8+ T cells in TSST-1-induced production of TNF-α and TNF-β. The expression of MHC class II molecules on AC was required in the response. 相似文献
40.
G. S. Yakobson S. G. Dobrovol'skaya G. M. Vakulin 《Bulletin of experimental biology and medicine》1978,85(4):502-506
The pattern of injury and repair in the liver of Wistar rats depending on sex, the phase of the estrous cycle, and also under the conditions of deficiency of female sex hormones and after injection of -estradiol into ovariectomized rats was studied by morphometric, histo chemical, and electron-microscopic methods. Structural disturbances caused by CCl4 were found to be increased and reparative reactions inhibited in the liver of females both during the period of a natural increase in the blood estrogen concentration and under the influence of exogenous estradiol, and ovariectomy also had a protective effect. In males, structural changes in the liver were more marked than in females with a low blood estrogen level and differend only a little from those in females during the period of increased secretion of sex steroids.Central Research Laboratory, Novosibirsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 4, pp. 460–464, April, 1978. 相似文献