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51.
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   
52.
抗肿瘤药复方三生注射液的研究   总被引:1,自引:0,他引:1  
复方三生注射液是由生附片等六味中药组成的静注用灭菌水溶液。本文综合报道了该制剂的制备方法,质量分析,抗肺癌作用的药理及临床等研究的主要内容。结果表明,本品是治疗中晚期肺癌有效的中药复方注射剂。  相似文献   
53.
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   
54.
High-resolution two-dimensional gel electrophoresis (2-DGE) was used to analyse plasma samples and partially purified cold agglutinins (CA) obtained from two selected patients. Both presented an acute hemolytic anemia with CA of high thermal amplitude, normal immunoglobulin levels, no detectable paraproteinemia, and no clinical evidence of a malignant B-cell disorder. The electrophoretograms of their plasma showed evident alternations of the "normal" protein profile, which were directly related to hemolysis (absence of the spots of haptoglobin and in one case of those of hemopexin), but no monoclonal gammopathy. The electrophoretograms of their purified CA revealed two clearly different spot patterns respectively corresponding to a monoclonal IgM and to polyclonal IgM. These results show that the clonality of CA associated with hemolytic anemia can be easily determined by 2-DGE. This technique may be very useful to discriminate chronic cold agglutinin disease in the early phase from "parainfectious" CA.  相似文献   
55.
Summary By using a radioreceptor assay GABA was detectable in rat interscapular brown adipose tissue (IBAT), the levels being 1% those of CNS and 10-fold those of peripheral plasma. Injection of the glutamic acid decarboxylase (GAD) inhibitor 3-mercaptopropionic acid lowered IBAT GABA levels by about half while injection of the GABA transaminase inhibitor -acetylenic GABA increased them by 230%. Rats kept at 4C for 14 days exhibited IBAT GABA levels that were about half those found at 22C. Accumulation of IBAT GABA after -acetylenic GABA increased by 2-fold in cold-exposed rats. Sympathetic denervation of IBAT prevented the effect of the cold environment on GABA content and impaired that on GABA accumulation. GAD activity was detectable in IBAT homogenates and isolated brown adipocytes. Exposure of rats to cold increased Vmax of GAD without modifying its Km, regardless of intactness of innervation. In binding studies with3H-GABA as a ligand, two types of sites were uncovered of KD=14 and 146 nM, respectively. In the presence of 2.5 mM Ca2+ bicuculline and baclofen were 57 and 46% as effective as GABA to displace3H-GABA from IBAT binding sites. The results indicate existence, possible synthesis and type A and B receptors of GABA in rat IBAT.  相似文献   
56.
Changes in myocardial contractility after an acute cold exposure following intracerebroventricular administration of opiate receptor agonists were studied in rat hearts isolated after Langendorff. Cold exposures were carried out individually for each animal in chambers at −10°C for 4 h. Thirty min before being exposed to cold the animals were administered in a brain ventricle 10 μl of μ- or δ-opiate receptor agonists (DAGO or DADLE, respectively). Isolation and perfusion of the hearts were performed directly after the cold exposure was over. The mechanism of reduction of myocardial contractility and coronary flow induced by an acute cold exposure is believed to include stimulation of μ-opiate receptors as one of its main components, and the effect of intracerebral hypertension on hemodynamic parameters is partially mediated through activation of δ-opiate receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 12, pp. 582–584, December, 1994 Presented by R. S. Karpov, Member of the Russian Academy of Medical Sciences  相似文献   
57.
We evaluated human physiological responses and the performance of manual tasks during exposure to severe cold (–25°C) at night (0300–0500 hours) and in the afternoon (1500–1700 hours). Thirteen male students wearing standard cold protective clothing occupied a severely cold room (–25°C) for 20 min, and were then transferred to a cool room (10°C) for 20 min. This pattern of exposure was repeated three times, for a total time of exposure to extreme cold of 60 min. The experiments were started either at 1500 hours or 0300 hours and measurements of rectal temperature, skin temperature, blood pressure, performance in a counting task, hand tremor, and subjective responses were made in each condition. At the end of the experiment at night the mean decrease in rectal temperature [0.68 (SEM 0.04)°C] was significantly greater than that at the end of the experiment in the afternoon [0.55 (SEM 0.08)°C, P<0.01]. After the second cold exposure at night the mean increase in diastolic blood pressure [90 (SEM 2.0) mmHg] was significantly greater than that at the end of the second cold exposure in the afternoon [82 (SEM 2.8) mmHg, P<0.01]. At the end of the second cold exposure at night, mean finger skin temperature [11.8 (SEM 0.8)°C] was significantly higher than that at the comparable time in the afternoon [9.0 (SEM 0.7)°C, P<0.01]. Similarly for the toe, mean skin temperature at the start of the second cold exposure at night [25.6 (SEM 1.5)°C] was significantly higher than in the afternoon [20.1 (SEM 0.8)°C, P<0.01]. The increased skin temperatures in the periphery resulted in increased heat loss. Since peripheral skin temperatures were highest at night, the subjects noted diminished sensations of thermal cold and pain at that time. Manual dexterity at the end of the first cold exposure at night [mean 83.7 (SEM 3.6) times·min–1] had decreased significantly more than at the end of the first cold exposure in the afternoon [mean 89.4 (SEM 3.5) times·min–1, P<0.01]. These findings of a lowered rectal temperature and diminished manual dexterity suggest that there is an increased risk of both hypothermia and accidents for those who work at night. Electronic Publication  相似文献   
58.
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   
59.
The present study aimed at investigating the spatial variability of skin temperature (T sk) measured at various points on the hand during convective and cold contact exposure. A group of 8 subjects participated in a study of convective cooling of the hand (60 min) and 20 subjects to contact cooling of the finger pad (5 min). Experiments were carried out in a small climatic chamber into which the hand was inserted. For convective cold exposure,T sk was measured at seven points on the palmar surface of the fingers of the left hand, one on the palmar surface and one on the dorsal surface of the hand. The air temperature inside the mini-chamber was 0, 4, 10 and 16°C. With the contact cold exposure, the subjects touched at constant pressures an aluminium cube cooled to temperatures of –7, 0 and 7°C in the same mini-chamber. ContactT sk was measured on the finger pad of the index finger of the left hand. TheT sk of the proximal phalanx of the index finger (on both palm and back sides), and of the middle phalanx of the little finger was also measured. The variation ofT sk between the proximal and the distal phalanx of the index finger was between 1.5 to 10°C during the convective cold exposure to an air temperature of 0°C. Considerable gradients persisted between the hand and fingers (from 2 to 17°C at 0°C air temperature) and between the phalanges of the finger (from 0.5 to 11.4°C at 0°C air temperature). The onset of cold induced vasodilatation (CIVD) on different fingers varied from about 5 to 15 min and it did not always appear in every finger. For contact cold exposure, whenT sk on the contact skin cooled down to nearly 0°C, the temperature at the area close to the contact skin could still be 30°C. Some cases of CIVD were observed in the contact skin area, but not on other measuring points of the same finger. These results indicated that local thermal stimuli were the main determinents of CIVD. Representative hand skin temperature may require five or more measuring points. Our results strongly emphasised a need to consider the large spatial and individual variations in the prediction and modelling of extremity cooling.  相似文献   
60.
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   
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