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71.
鞘内注射两性霉素B治疗隐球菌性脑膜炎的临床观察   总被引:1,自引:0,他引:1  
目的观察鞘内注射两性霉素B(amphotericin B,AMB)治疗隐球菌性脑膜炎的疗效和不良反应。方法回顾性分析1995-2006年作者医院治疗的8例隐球菌性脑膜炎患者的临床资料,8例患者均采用同时鞘内注射和静脉注射AMB并联合应用氟康唑或氟胞嘧啶治疗。结果痊愈4例,好转3例,死亡1例;鞘内注射后均有头疼、恶心呕吐及下肢麻痛等症状,并出现短暂性双下肢截瘫2例,尿潴留1例,意识障碍2例。结论反复行腰穿放脑脊液控制颅压并联合鞘内注射AMB治疗隐球菌性脑膜炎疗效肯定,但患者有不同程度不良反应。  相似文献   
72.
5-HT1A receptor agonists: recent developments and controversial issues   总被引:4,自引:0,他引:4  
During the last decade, serotonin (5-HT)1A receptors have been a major target for neurobiological research and drug development. 5-HT1A receptors have been cloned and a variety of selective agonists, such as the aminotetraline 8-OH-DPAT and the pyrimidinylpiperazine ipsapirone, have become available. Demonstrations of apparent intrinsic activity of these ligands at 5-HT1A receptors, however, depend highly on the particular assay system. This may be due to the possible existence of receptor subtypes and to assay (or brain region)-dependent differences in receptor reserve and the nature of receptor-effector coupling. Nevertheless, the apparent intrinsic activity of 8-OH-DPAT seems to be higher (although possibly not yet maximal) than that of the pyrimidinylpiperazines. In the brain, 5-HT1A receptors are located presynaptically as somatodendritic receptors on 5-HT neurons and postsynaptically in particular limbic and cortical regions. Although it is generally accepted that presynaptic 5-HT1A receptors control 5-HT neuronal activity, recent evidence suggests an additional role of postsynaptic 5-HT1A receptors in cortex as part of a negative feedback loop. Anxiolytic and antidepressive properties of selective 5-HT1A receptor agonists have now been confirmed by clinical studies. Although it is well established that the latter properties depend on theagonistic activity of these compounds, theoptimal level of intrinsic activity is still a matter of debate and may be dependent on the clinical indication. Such compounds may also have antiaggressive effects, and possibly anticraving effects (manifested by their alcohol intake-reducing effects in dependent animals), but the specificity of these so-called anti-impulsivity effects is still controversial and not yet tested clinically. Anticataleptic, antiemetic and neuroprotective properties have been demonstrated in different species. Behavioral studies on the mechanisms underlying the anxiolytic and antidepressive effects have examined the relative contribution of pre-and postsynaptic 5-HT1A receptors by means of local cerebral application and lesion techniques. Most evidence points towards a critical involvement of presynaptic receptors in the anxiolytic effects of 5-HT1A receptor agonists (although a possible contribution of postsynaptic receptors cannot be excluded). With regard to the antidepressive properties, a case can be made for the reverse; i.e., a strong involvement of postsynaptic receptors and a questionable contribution of presynaptic receptors. However, as the therapeutic effects of those 5-HT1A receptor (partial) agonists which have been tested clinically require repeated administration, attention has been directed increasingly towards chronic studies. These studies have shown that a number of electrophysiological, biochemical, behavioral and endocrinological 5-HT1A receptor-related events adapt differentially to repeated or sustained administration. Thus, several hypotheses accounting for the delayed onset of action have been advanced. Among these, time-dependent downregulation /desensitization of eitherpre- orpostsynaptic 5-HT1A receptors, or cortical 5-HT2 receptors have received much attention. However, these hypotheses have their weaknesses, and it is argued thatfunctional sensitization of particular postsynaptic 5-HT1A receptor-mediated events remains a valuable alternate hypothesis. Basic research on the role of 5-HT1A receptors in psychopathology and in the therapeutic effects of clinically effective therapeutics, as well as on the mechanism of action of 5-HT1A receptor ligands, will enable rational design of ligands with particular profiles of intrinsic activity at different 5-HT1A receptor populations, and may contribute to a more efficient treatment of a multiplicity of brain disorders.  相似文献   
73.
通过归纳护理管理论文自选课题中常见的错误,即选题重复、过大、偏离、有悖伦理、缺乏实用性和可行性等,提出立题前检索、选择贴近护理管理领域的课题、认真筛选专家进行论证、选择易于操作的课题等改进措施。  相似文献   
74.
尿激酶原是新一代特异性溶栓药。为进一步提高该药的安全性和有效性,本文从使用剂量、给药方案、与其他溶栓药伍用,及给药途径等方面提出了意见,供临床医生使用中参考。  相似文献   
75.
Purpose. The mucoadhesiveness of polymer-coated liposomes was evaluated to develop a novel drug carrier system for oral administration of poorly absorbed drugs such as peptide drugs. Methods. Multilamellar liposomes consisting of dipalmitoylphosphatidylcholine (DPPC) and dicetyl phosphate (DCP) (DPPC:DCP = 8:2 in molar ratio) were coated with chitosan (CS), polyvinyl alcohol having a long alkyl chain (PVA-R) and poly (acrylic acid) bearing a cholesteryl group. The adhesiveness of the resultant polymer-coated liposomes to the rat intestine was measured in vitro by a particle counting method with a Coulter counter. The CS-coated liposomes containing insulin were administered to normal rats and the blood glucose level was monitored. Results. The existence of polymer layers on the surface of liposomes was confirmed by measuring the zeta potential of liposomes. The CS-coated liposomes showed the highest mucoadhesiveness and the degree of adhesion was dependent on the amount of CS on the surface of the liposomes. The blood glucose level of rats was found to be significantly decreased after administration of the CS-coated liposomes containing insulin. The lowered glucose level was maintained for more than 12h after administration of the liposomal insulin, which suggested mucoadhesion of the CS-coated liposomes in the intestinal tract of the rats.  相似文献   
76.
Serotonin (5-HT) may be inhibitory to micturition at a spinal level. A potential mechanism of action for serotonergic inhibition of bladder function is a depression of the ascending limb of the supraspinal reflex mediating micturition. Ascending activity evoked by pelvic nerve stimulation was recorded in the thoracic spinal cord of anesthetized cats. For comparison, spinal reflex activity evoked by pelvic nerve stimulation was recorded on the pudendal nerve. The effects of intrathecal administration of serotonergic agents were examined to determine whether spinal and supraspinal responses to bladder afferent activation were modulated by 5-HT. Methysergide (60 nmol), a non-selective serotonergic antagonist, increased ascending activity by 61±7% and depressed spinal reflex activity by 38±6%. Zatosetron (10 nmol), a 5-HT3 antagonist had a similar effect on both activities (increased by 93±24% and decreased by 77±7%, respectively). The effect on ascending activity of blocking 5-HT3 receptors was also confirmed with ICS 205930 and MDL 72222. 2-Methyl-5-HT (800 nmol), a 5-HT3 agonist, depressed ascending activity to 46±9% of control, but enhanced spinal reflex activity by 73±92%. These results demonstrate that stimulation of 5-HT3 and methysergide-sensitive 5-HT receptors can inhibit ascending activity and facilitate spinal reflex activity elicited by activation of bladder afferents. It is suggested that descending serotonergic pathways may participate in the spinal coordination of urinary continence.  相似文献   
77.
Abstract. Objectives. To evaluate the efficacy of self-administered subcutaneous sumatriptan in the acute treatment of early-morning migraine attacks. Design. A double-blind, randomized, placebo-controlled, cross-over study. Setting. Thirteen neurology centres in France. Subjects. Patients of either sex, 18–65 years old, with two to six attacks of migraine (according to the International Headache Society (IHS) criteria, with or without aura) per month, of which at least two had to be early-morning migraine attacks. One-hundred-and-one patients were included, 96 being evaluable for the first attack and 81 for the cross-over design. Interventions. Two migraine attacks (grade 2/3) were treated with sumatriptan (6 mg) or placebo, with an optional second injection 1–24 h later. Main outcome measures. The primary end-point was headache relief: reduction in headache severity from grade 2/3 (moderate/severe) to grade 1/0 (mild/none) 2 h after treatment. Results. Sumatriptan was superior to placebo for headache relief (32 [78%] vs. 11 [28%] at the first attack; 29 [73%] vs. 8 [20%] at the second; P < 0.001). Because of a significant carry-over effect for some of the secondary end-points, a parallel-group analysis of the first attack was performed, which confirmed a significantly higher efficacy of sumatriptan for all end-points: pain-free rate (22 [46%] vs. 7 [15%]; P = 0.001) and use of a second injection (26 [53%] vs. 38 [81%]; P = 0.004). Sumatriptan was preferred by 74% of patients vs. 17% for placebo, and 9% expressed no preference (P < 0.0001). After complete relief, headache reappeared in 8/23 (35%) patients with sumatriptan and 3/7 (43%) with placebo. Adverse events were significantly more frequent with sumatriptan but they were minor and transient. Conclusion. Subcutaneous sumatriptan auto-injection is an effective and well-tolerated acute treatment of early-morning migraine attacks allowing earlier return to normal activity.  相似文献   
78.
ONO—802阴道给药抗早孕50例临床效果观察   总被引:2,自引:0,他引:2  
本文报告了停经56天以内的早孕妇女应用ONO-802阴道栓剂抗早孕的临床观察及效果。50例早孕妇女住院观察24小时,阴道投药1枚(1mg/枚),5枚为一疗程。用药后1周、2周、4~6周门诊随访,复查尿HCG、血红蛋白。在第二周随访时判断用药效果。临床结果:总有效率82%,其中完全流产76%,不全流产6%,失败率18%。ONO-802使用方便,副反应轻,是深受广大妇女欢迎的一种非手术终止妊娠的方法。本项试验结果通过与国内PG 联合用药的结果和研究资料对比,ONO-802如果能与丙睾、R2323、天花粉等联合应用,将会提高其抗早孕的有效率。  相似文献   
79.
Summary The efficacy of intranasally administered neostigmine was tested in 22 patients with generalized myasthenia gravis (MG). Topical therapy to the highly vascularized oropharynx proved to be quickly effective in 5–15 min both clinically and electrophysiologically. Twenty-eight MG patients were then recruited from different centres and their morning doses of oral pyridostigmine were substituted with intranasal neostigmine over a period of 2 or 3 weeks. Intranasal neostigmine proved to be equally efficacious in this regimen. No side-effect was noted even in 4 patients treated in this way for 1 year. Intranasal administration of anti-acetylcholinesterase may be very beneficial: (1) for patients with irregular absorption of oral doses; (2) early in the morning and every time a fast and temporary effect is needed; (3) in bulbar impairment and emergencies, in which a handy atomizer may be life-saving.Presented in part at the XIV World Congress of Neurology, New Delhi, 22–27 October 1989  相似文献   
80.
Summary Twelve patients with essential hypertension receiving captopril monotherapy or captopril in conjunction with a diuretic had their 24-h blood pressure profiles monitored using an automatic, non-invasive ambulatory method. The study examined the efficacy of once a day versus twice a day administration of the ACE inhibitor in controlling blood pressure.Six untreated subjects with borderline hypertension were also studied using the same monitoring equipment and with the same frequency, to act as controls because of the possibility of repeated use of the device causing a familiarisation effect.The results obtained indicated that if anything, the once daily dosing produced marginally better blood pressure values. The amplitude of the diurnal blood pressure variation was reduced on a second-wearing of the monitoring equipment suggesting some degree of familiarisation with the apparatus.  相似文献   
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