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71.
Photic evoked responses were recorded from the striate cortex of Long-Evans hooded intact, monocular visual deprivation (MD) and MD treated with NGF rats. The averaged visual evoked responses (AVER) were obtained from both hemispheres and provided comparison after binocular photic stimuli between the contralateral and the ipsilateral striate cortex with relation to the MD eye. One month of monocular visual deprivation at the critical period of development resulted in marked reduction of the amplitudes of AVER components as compared to the control recordings (P < 0.001). These changes of the AVER could be prevented by NGF infusion to lateral ventricle at the dosage of 2.0–2.4 μg/day for four weeks during the monocular deprivation. In conclusion, the change of AVER amplitudes induced by monocular visual deprivation during the critical period of development can be prevented by NGF infusion to lateral ventricle. 相似文献
72.
73.
邓敦 《浙江中西医结合杂志》2023,33(6)
摘要:目的:观察益气活血补肾壮骨方在骨质疏松症(气滞血瘀型)患者双膦酸盐药物休假期的临床疗效和不良反应等。方法:将本院2019年12月—2021年7月就诊120例气滞血瘀型骨质疏松症双膦酸盐药物休假期患者按照随机数字表均分为两组。对照组予钙片、阿法骨化醇胶囊、金天格治疗,研究组予钙片、阿法骨化醇胶囊加用益气活血补肾壮骨方治疗。治疗6个月后,比较两组患者骨代谢、细胞因子、骨密度、 健康调查简表(SF-36评分)、脆性骨折发生率、骨折风险评估、中医证候积分、疗效和不良反应等。结果:治疗前两组各项指标比较差异无统计学意义(p>0.05)。治疗后研究组骨代谢低于对照组(BGP25.69±4.07vs26.37±4.16ng/mL、PINP35.79±7.38vs37.02±8.12ng/mL、CTX0.85±0.14vs1.26±0.21mmol/L、TRACP8.93±1.26vs13.06±2.59u/L),细胞因子(IL-1:26.36±3.07vs23.75±2.93pg/mL、IL-6:82.71±6.25vs78.62±9.08pg/mL、TNF-α5.03±1.02vs3.81±1.09ng/L)高于对照组,差异有统计学意义(p<0.05)。研究组SF-36评分(87.46±8.32vs70.62±6.59)、西医有效率(86%vs80%)、中医症候积分(23.46±5.32vs21.62±4.59)、中医疗效有效率(84%vs76%)高于对照组,左股骨颈BMD(0.68±0.05vs0.70±0.06g/cm2),脆性骨折发生率(2%vs8%)、骨折风险评估(1.49±0.32vs2.63±0.47)低于对照组,但差异无统计学意义(p>0.05)。结论:益气活血补肾壮骨方联合钙片、阿法骨化醇胶囊可改善双膦酸盐药物假期患者(气滞血瘀型)骨代谢水平,抑制骨吸收和炎性因子水平、促进骨形成、提高骨密度,降低脆性骨折发生率和骨折风险,提高中医症候积分、生活质量,从而提高疗效,疗效水平与金天格相当。 相似文献
74.
M. Cynader N. Berman A. Hein 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1976,25(2):139-156
Summary Evidence that there is a critical period during which response characteristics of neurons in visual cortex of the cat may be influenced has been provided in several studies, which suggest that the period of influence is restricted to the first few months of life. Using a somewhat different experimental procedure, we have obtained evidence that cortical units retain plasticity long after the end of this period has passed. In our procedure prolonged visual deprivation was followed by exposure in a normal visual environment. The animals were maintained throughout the first year of life either in total darkness or in an enclosure illuminated intermittently by a strobe light. Following the period of deprivation, electrophysiologic recordings were taken from some of these animals. The remaining cats were permitted 6–12 months in a normally-illuminated environment prior to recording. Cats of the same age reared from birth in a normally lit environment were also recorded.Cortical neurons in cats deprived of any normal visual experience rarely show orientation selective responses. In animals allowed subsequent normal visual experience about one-half of the units studied exhibited this property. This level of response specificity is intermediate between that of normally-reared and recently-deprived animals. While most cortical units in normally-reared cats exhibit direction selectivity, this property is rarely observed in the recovery cats. A number of unit types which are rarely observed in either normal or totally deprived animals were encountered in cats that had normal exposure following prolonged deprivation. A convergent strabismus was observed, in contrast with the divergent strabismus often shown by cats immediately following prolonged visual deprivation. This shows that ocular alignment as well as cortical unit properties can remain plastic in the adult.Supported by NRC Grant No. A9939 and M.R.C. Grant No. MA5201 (to M.C.) and Grants from NIH and the Sloan Foundation (to A.H.). 相似文献
75.
广州市至灵学校167名学员智残原因的调查分析 总被引:2,自引:1,他引:2
本文以广州市至灵学校(智低)167名学员为研究对象,完成智力测验、体格检查和染色体分析.并且追溯围产期和出生后的种种异常.询查智力低下的家族史。综合分析有关资料,显示围产期的某些不利因素、遗传与先天疾病,以及婴幼儿中枢神经系统疾病是主要的发病原因。从而指出,加强优生咨询、重视围产期保健、提高产前诊断和产程中的监护水平、早期防治胎婴儿中枢神经系统损伤和疾病等,是降低智残儿发生率的重要措施。 相似文献
76.
过敏性紫癜急性期血液流变性改变及其临床意义 总被引:8,自引:0,他引:8
为了研究过敏性紫癜(HSP)急性期血液流变性改变及其临床意义,采用NXE-I型锥板式粘度计,测定了21例HSP急性期血液流变学各项指标。结果表明,HSP组全血粘度、血浆粘度、红细胞聚集性增多显著高于对照组;氧释放系数OD值较对照组明显降低;HSP患儿红细胞压积、血小板计数、血清IgA和IgM呈明显升高。提示HSP时存在明显的血液流变性异常,其发生与血液浓缩、高Ig血症等因素有关。及时治疗HSP高粘滞血症对减轻症状、防止复发是十分有益的 相似文献
77.
Acute hypervolemia induced in experiments on dogs by infusion of dextran, did not produce decompensation of the circulation in animals whose cardiac output was sharply depressed in the postresuscitation period after circulatory arrest lasting 15 min. The increase in the venous return and change in the conditions of the peripheral circulation as a result of dextran administration temporarily increased the central venous pressure, caused a lasting increase in the arterial pressure, cardiac output, stroke volume, work of the left ventricle, and total oxygen consumption by the body, and lowered the peripheral vascular resistance. In model experiments on dogs subjected to isolated compression ischemia of the brain for 20 min, a low cardiac output syndrome also developed.Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 7, pp. 787–789, July, 1976. 相似文献
78.
Sheikh-Zade YR Galenko-Yaroshevskii PA Cherednik IL 《Bulletin of experimental biology and medicine》2002,134(1):1-4
We propose a new mechanism of atrial fibrillation basing on the results of 30 series of acute experiments on anesthetized cats. In brief, combination of two or more arrhythmogenic factors shortens the interval between the inward and outward ionic currents in cardiomyocytes to a critical value. Under these conditions repolarization of cardiomyocyte membrane reaches the excitation threshold before complete inactivation of the depolarizing currents. This inevitably results in autoexcitation of myocytes (or extrasystole), that in turn promotes repolarization. Once occurred, autoexcitation turns into self-triggering activity resembling tachyarrhythmia paroxysm. 相似文献
79.
Matsuyama A Yonemitsu N Hayashida S Watanabe K Sugihara H Inokuchi A 《Pathology international》2003,53(1):46-50
Osteosarcoma is one of the neoplasms that may occur following exposure to radiation. A case of osteosarcoma arising in the craniofacial bone with a short latency period of 3 years after radiotherapy for maxillary squamous cell carcinoma is described. A 64-year-old-man underwent right partial maxillectomy and chemoradiotherapy due to squamous cell carcinoma of his right maxillary sinus. Histologically, the tumor was composed of moderately differentiated squamous cell carcinoma with a component of spindle cell carcinoma. Three years later, osteosarcoma developed in the craniofacial bone within the irradiation field of the first tumor. Detailed histological examination demonstrated that there was no component of osteosarcoma in the first tumor or squamous cell carcinoma in the second tumor. Radiation-induced osteosarcoma usually occurs after a long latency period of more than 10 years after the radiotherapy. In this case, osteosarcoma was possibly a radiation-induced osteosarcoma with a short latency period of 3 years. 相似文献
80.
M. Schmelz C. Forster R. Schmidt M. Ringkamp H. O. Handwerker H. E. Torebjörk 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1995,104(2):331-336
The slowing of impulse conduction during the relative refractory period has often been used to assess activation of C-fibers, in particular, in human microneurography. This study aimed to evaluate the sensitivity of this method and the factors affecting it. Thirty cutaneous C-fibers were recorded from the peroneal nerves of healthy human subjects. Intracutaneous electrical stimulation in the receptive field at 4 s intervals, after some minutes of adaptation, induced spike discharges at constant latency. One or more conditioning stimulus pulses were interpolated at different intervals and the increase in latency after the subsequent regular pulse was assessed. The latency shift was found to depend on the number of interposed pulses, on the time interval between conditioning and conditioned stimulus, and on the conduction velocity of the C-unit. The increase in latency was larger with greater distance between stimulating and recording electrodes, indicating a contribution of the conductile membrane over its whole length. On the other hand, slowing was more pronounced, on average, in slower conducting C-units and conduction velocities were slower when recordings were performed more distally. These findings indicate that the slower terminal nerve branches contribute most to the latency increases. Even a single additional spike in between two regular pulses caused a reliable latency shift of 1.2±0.2 ms (mean ±SEM) and additional pulses lead to an approximately linear latency increase (2 pulses: 2.3±0.3 ms; 4 pulses: 5.9±0.7 ms). In contrast to the number of interposed stimuli, different intervals between interposed and regular stimuli had only a minor impact on the latency shifts. It is concluded that latency shifts are reliable indicators of C-fiber activation, being sensitive enough to detect even single spike responses. Furthermore, latency increases may be used as a relative measure of C-fiber activation, e.g., when comparing responses to stimuli of different strength. 相似文献