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101.
本文探讨了ASA剂量与药效的关系及血ASA、SA药物浓度监测的临床意义,结果表明:(1)ASA剂量与6-keto-PGF_(1α)抑制率呈正相关(P<0.01),而与TXB_2及PAgR抑制率无相关性(P>0.1);(2)本文采用HPLC内标法同时测定血ASA和SA浓度,结果准确,方法简便;(3)当口服小剂量ASA防治CI时,监测血ASA和SA以调整ASA用药剂量的临床价值并非十分重要。  相似文献   
102.
重症肌无力病人乙酰胆碱受体抗体的测定及临床意义   总被引:7,自引:0,他引:7  
用ELISA(固相酶联免疫吸附)法测定172例MG病人血清乙酰胆碱受体抗体(AchRab),结果显著高于健康献血员组和非MG病人组。不同性别、病程及临床类型与AchRab无相关性,但41~50岁组的显著高于其他年龄组。67例类固醇激素治疗组、22例大剂量两种球蛋白治疗组、12例胸腺切除术组及3例MG危象病人24次血浆交换疗法(PE)组,治疗后伴随肌无力症状的好转,AchRab均显著低于治疗前。结果表明:AchRab测定为MG诊断提供了可靠的实验依据,为类固醇激素、大剂量丙种球蛋白、胸腺切除术和PE等治疗MG提供理论依据和疗效评定的实验指标,进一步证实了MG免疫学发病机理。  相似文献   
103.
104.
The course of the organic brain disease caused by human immunodeficency virus (HIV-1) was evaluated in a follow-up study. The primary material included 200 consecutive HIV-1 infected persons. Sixty-one subjects, in whom other brain-affecting factors were excluded, consented to the follow-up. They underwent 278 radiologic examinations: computed tomography, magnetic resonance imaging, or a combination of both (mean 4.6 examinations/subject). Clinical neurologic status and, in 40 subjects, cognitive performance were repeatedly evaluated. Sixteen subjects were followed up until death and 11 of them were autopsied. Median follow-up time was 27 mo (range 2.5–66 mo). The most common radiologic finding was atrophy, found in 19 subjects at study entry and developing in 10 subjects during the study. Twenty-four subjects (39%) showed the development and/or progression of atrophy. Atrophic changes progressed most rapidly in acquired immunodeficiency syndrome (AIDS), but mild developing/progressive atrophy was found even in 33% of asymptomatic or neurologically intact subjects. Cognitive and radiologic worsening were simultaneous in 6/7 subjects with declining neuropsychologic test performance. Signal intensity changes including HIV-1 leukoencephalopathy appeared in AIDS patients with clear cognitive decline.  相似文献   
105.
The complete sequence of the cDNA encoding the neuropeptide Y (NPY) Y1-receptor has recently been deduced from a rat brain library, and the presence of messenger ribonucleic acid (mRNA) encoding Y1-receptor protein has been demonstrated within the brain. Using quantitative in situ hybridization histochemistry, the content and distribution of Y1receptor and preproNPY mRNAs have been investigated in the hypothalamic arcuate nucleus of adrenalectomized rats receiving glucocorticoid replacement therapy for 12 days by means of either high doses of dexamethasone in their drinking water or by subcutaneous corticosterone pellets. Basal metabolic parameters such as weight gain or loss, blood glucose and plasma insulin were monitored: Dexamethasone treatment induced weight loss and a state of hyperinsulinemia with normoglycemia, while corticosterone treated animals displayed metabolic parameters identical to sham ADX animals. Within the arcuate nucleus of glucocorticoid treated animals, levels of Y1receptor and preproNPY mRNAs were increased. In contrast, adrenalectomy itself had no effect upon Y1-receptor mRNA levels or preproNPY mRNA levels in the arcuate nucleus. These studies demonstrate that glucocorticoids exert a stimulatory action on levels of Y1-receptor mRNA and preproNPY mRNA levels in the hypothalamic arcuate nucleus. This is the first evidence to suggest that the expression of a neuropeptide-receptor gene in the central nervous system may be directly sensitive to peripheral hormonal signals.  相似文献   
106.
本文报告口服Sumatriptan 100mg对偏头痛急性发作119例次的治疗结果。治疗后4h内显效91例次(76.5%),好转16例次(13.4%),无效12例次(10.1%),总有效率为89.9%。对偏头痛伴随症状恶心、呕吐和畏光、畏声的缓解率分别为94.2%、96%和94.3%。  相似文献   
107.
Ten patients with DSM-III-R obsessive-compulsive disorder (OCD) underwent the desipramine (DMI) growth hormone (GH) stimulation test as well as the dexamethasone suppression test (DST). The results were compared with the responses in a group of matched healthy controls. The GH response to DMI did not differ between patients and controls and 9 of 10 patients showed cortisol suppression in response to dexamethasone. The data suggest that neither alpha 2 adrenergic dysfunction nor DST non-suppression are features of primary OCD.  相似文献   
108.
Glutamate is the primary excitatory amino acid in the mammalian central nervous system. Normal excitation of glutamate receptors initiates the stimulation of phospholipases and lipases with the generation of second messengers that are necessary for normal cell function. The overstimulation of glutamate receptors can initiate a cascade of biochemical events including stimulation of membrane phospholipid turnover, excessive calcium entry, abnormal phosphorylation, and proteolysis. These events may be responsible for neuronal injury and degeneration found in Alzheimer disease, ischemia, spinal cord trauma, epilepsy, and Huntington disease.  相似文献   
109.
Platelet aggregation and thrombosis play an important role in the onset of acute coronary events. Regardless of the stimulus for activation, platelet thrombus formation is ultimately regulated through the IIb/IIIa receptor complex. The effects of oral administration of xemilofiban, a non-peptide mimetic of the RGDF sequence of the IIb/IIIa receptor complex, on thrombus formation were evaluated in a canine model. Xemilofiban significantly reduced platelet deposition on severely damaged arterial wall. Platelet deposition was reduced at both low (13 ± 1 from 56 ± 18 × 106 platelets cm−2; P  < 0.05) and high (23 ± 2 from 111 ± 21 × 106 platelets cm−2; P  < 0.01) shear rates. Platelet deposition was reduced to a monolayer as seen by electron microscopy (platelet–vessel wall interaction). Therefore, the availability of an orally active IIb/IIIa antagonist for chronic use may have significant value in preventing thrombus formation in those clinical situations associated with severe arterial injury, such as atherosclerotic plaque disruption.  相似文献   
110.
The opioid transmitters enkephalin and dynorphin are known to regulate pallidal output and consequently cortical excitability. Indeed, abnormal basal ganglia opioid transmission has been reported in several involuntary movement disorders, including levodopa-induced dyskinesias in Parkinson's disease (PD), tardive dyskinesias/dystonia, Huntington's disease, and Tourette's syndrome. Moreover, a previous 11C-diprenorphine PET study investigating levodopa-induced dyskinesias found reduced opioid receptor availability in PD with but not without dyskinesias. We wished to investigate if a similar alteration in basal ganglia opioid binding was present in DYT1 primary torsion dystonia (PTD). Regional cerebral 11C-diprenorphine binding was investigated in 7 manifesting carriers of the DYT1 gene and 15 age-matched normal controls using a region-of-interest (ROI) approach and statistical parametric mapping (SPM). No difference in regional mean 11C-diprenorphine binding was found between DYT1-PTD and controls, and no correlation between the severity of dystonia and opioid binding was seen. We conclude that aberrant opioid transmission is unlikely to be present in DYT1-PTD and altered opioid transmission is not a common mechanism underlying all disorders of involuntary movement.  相似文献   
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