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91.
胸腺免疫抑制组分的抗变态反应作用 总被引:1,自引:0,他引:1
整体实验表明,胸腺免疫抑制组分肌内注射1wk对大鼠被动皮肤过敏反应(8、20、50和125mg·kg-1)兔Arthus反应(4和12mg·kg-1)均有明显的抑制作用。体外实验表明,该药能抑制致敏豚鼠离体回肠平滑肌的过敏性收缩,IC50为446.7mg·L-1。上述结果表明,胸腺免疫抑制组分有抗Ⅰ和Ⅲ型变态反应的作用。 相似文献
92.
Summary By ligating the proximate left anterior descend (LAD) of coronary artery and inducing the ventricular fibrillation with electrical
stimulation, the preventive effects of electroacupuncture (EA) on ventricular fibrillation were observed. The results showed
that the ventricular fibrillation threshold (VFT) of rats with acute ischemic myocardium was raised after acupuncturing some
acupoints, which could prevent the occurrence of ventricular fibrillation. Furthermore, the combination of EA and propranolol
could enhance the VFT effectively, and they showed a good synergistic effect.
This project was supported by grants from National Natural Science Foundation of China (No. 3870563). 相似文献
93.
盐酸氯胺酮-β-环糊精包合物的研究 总被引:4,自引:1,他引:3
采用正交设计法对饱和水溶液法制备盐酸氯胺酮-β-环糊精包合物的温度、时间及投料比进行选优,显微观察包合物形态,UV和X-射线衍射法测试包合物晶形变化,品尝包合物味觉效果,并测定其稳定性及溶出度。结果表明,按1:2主客克分子比,于25℃电动搅拌3h,制备包合物的包合率和收率较高,包合物已形成一种新物相,具有稳定性高,无苦味及缓释性能。 相似文献
94.
Preliminary observations on the activity of progabide, administered as monotherapy in complex partial seizures 总被引:2,自引:0,他引:2
E Benassi G Besio G P Bo L Cocito M Maffini P Mainardi P L Morselli C Loeb 《International journal of clinical pharmacology research》1988,8(5):353-361
Progabide (PGB), a gamma-amino-butyric acid receptor agonist, was administered, according to an open-label long-term design, to 40 adult patients suffering from complex partial seizures, with or without secondary generalization, whose response to carbamazepine (CBZ) monotherapy was unsatisfactory. A reference-baseline period of two months with carbamazepine monotherapy was followed by a two-month "add-on" period where increasing doses of progabide were added without modifying the CBZ regimen; then CBZ was withdrawn over 15-60 days and patients were followed up to 12 months' progabide treatment. Twenty-seven patients completed the trial but 12 of them had to be returned to CBZ + PGB bitherapy due to an increase of seizures following CBZ withdrawal. A definite therapeutic effect could be observed in nine patients on PGB monotherapy and in six patients on CBZ + PGB bitherapy. Side-effects of clinical relevance occurred in three cases and were represented by remarkable anxiety in two patients and a rise in serum glutamic oxalo-acetic acid and pyruvic transaminases with clinical symptoms of liver dysfunction in one, with rapid recovery following progabide discontinuation. In conclusion, progabide was effective against complex partial seizures in about 40% of patients not responding satisfactorily to available antiepileptic drugs. Although the withdrawal of previous antiepileptic drugs was not possible in all patients, progabide monotherapy was sometimes more effective than CBZ monotherapy, and several patients in whom bitherapy had to be restored benefited from the association of progabide. 相似文献
95.
背景 妊娠期糖尿病(GDM)的发病率居高不下,且在全球普遍流行,在中国GDM发生率高达14.8%,妊娠期高血糖严重威胁母婴健康。目的 探讨GDM孕妇采用基于正念的补充替代疗法的干预效果。方法2021年3—12月采用便利抽样法选取在长沙市中心医院门诊进行产前检查的64例GDM孕妇,采用随机数字表法分为试验组(n=31)和对照组(n=33)。对照组采取常规心理护理、饮食宣教、运动指导,试验组在常规心理护理基础上采用8周基于正念的补充替代疗法。收集患者基线资料,比较两组孕妇干预前后血糖水平及炎性因子、丝氨酸蛋白抑制剂(vaspin)水平,随访新生儿结局指标(出生体质量、随机血糖)。结果 干预后试验组孕妇空腹血糖、餐后1 h血糖、餐后2h血糖、白介素6、白介素8、肿瘤坏死因子α、vaspin水平低于对照组(P<0.05);干预后试验组空腹血糖、餐后1h血糖、餐后2 h血糖、白介素6、白介素8、肿瘤坏死因子α、vaspin低于干预前(P<0.05);试验组GDM孕妇分娩时体质量、分娩时体质指数、妊娠期增重、分娩前糖化血红蛋白,新生儿出生体质量均低于对照组(P<0.05),试验组... 相似文献
96.
目的观察双歧杆菌三联活菌肠溶胶囊联合阿奇霉素序贯疗法治疗对肺炎支原体肺炎腹泻患儿胃肠炎症的调节作用。 方法将肺炎支原体肺炎伴腹泻的患儿106例均分为对照组和观察组。对照组采用阿奇霉素序贯疗法治疗,观察组在对照组基础上给予双歧杆菌三联活菌肠溶胶囊治疗。比较两组疗效和肠道菌群失调发生率。比较两组胃肠激素、降钙素原(PCT)、C反应蛋白(CRP)、中性粒细胞百分比(NEUT%)、嗜酸性粒细胞计数(EOS)水平。 结果观察组总有效率高于对照组(P<0.05)。治疗后,两组胃肠激素和PCT、CRP、NEUT%、EOS较治疗前下降(P<0.05),且观察组低于对照组(P<0.05)。观察组肠道菌群失调发生率低于对照组(P<0.05)。 结论双歧杆菌三联活菌肠溶胶囊联合阿奇霉素序贯疗法治疗可减轻肺炎支原体并腹泻肺炎患儿炎症反应,调节胃肠激素,降低患儿肠道菌群失调的发生。 相似文献
97.
Dr. A. Härfstrand K. Fuxe L. Agnati B. Fredholm 《Journal of neural transmission (Vienna, Austria : 1996)》1989,75(2):83-99
Summary Interactions between a 2-adrenoreceptor agonist and neuropeptide Y (NPY) binding sites have been studied in the rat medulla oblongata (MO) using biochemical binding techniques as well as quantitative autoradiography. Tritiated para-amino clonidine (3H-PAC; 2-adrenoceptor agonist), idazoxan (3H-IDA; 2-adrenoceptor antagonist) and iodinated neuropeptide Y (125I-NPY) were used as radioligands. (1) Neuropeptide Y (NPY; 10–8M) but not bovine pancreatic polypeptide (BPP) nor peptide YY (PYY 10nM) increased the KD value of3H-PAC binding sites. However, intraventricular administration of a high dose of NPY (1.25nmol) did not change the3H-PAC binding characteristics in MO membrane preparations of these animals. (2) GTP 10–4 lowered the affinity of3H-PAC binding. NPY (10 nM) had no additional effect, nor did NPYinfluence the GTP induced shift in potency of clonidine to displace3H-IDA from its binding sites. (3) In the autoradiographical experiments NPY (10nM) significantly reduced3H-PAC binding (2nM) in the nucleus tractus solitarius (NTS) area by 35%. (4) When clonidine, either given centrally in vivo (3.75nmol) or in vitro (10 nM) the binding of125I-NPY was reduced (34 and 24%, respectively) in the NTS. When the monoamine receptors were irreversibly blocked in vivo by N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 10 g i.e. 24h)125I-NPY (0.5 nM) binding was increased by 137% in the NTS. This effect of EEDQ was prevented by pretreatment with the 2-adrenoreceptor antagonist idazoxan.These results provide support for a direct intramembrane interaction between the 2-receptor and the NPY receptor within the NTS and may be of importance in central cardiovascular regulation. 相似文献
98.
Ljiljana Ševaljević Sanja Marinković Desanka Bogojević Svetlana Matić Bogdan Bošković 《Archives of toxicology》1989,63(5):406-411
We have studied the effect of soman intoxication on serum acute phase reactants (APR) levels, and the relationship of the APR and corticosterone concentrations and the immunosuppressive activity of the serum. One day after the injection of 1.8 LD50 soman the concentrations of 2-macroglobulin (2-MG) and 1-acid glycoprotein (AGP) in the serum of antidote protected rats increased 4- and 7-fold, respectively, whereas those of hemopexin (Hx), haptoglobin (Hp) and cysteine protease inhibitor (CPI) were two to three times higher than in the controls. A similar magnitude of increase of serum acute phase reactants levels was observed when 0.3 LD50 soman was administered at 24-h intervals over the 5-day period. The relationship of changes in the APR concentration, corticosterone level and immunosuppressive activity of the serum was also comparable to that observed in the acute phase response to tissue injury. 相似文献
99.
Han B Jaurequi J Tang BW Nimni ME 《Journal of biomedical materials research. Part A》2003,65(1):118-124
While attempting to find a suitable crosslinking reagent for biopolymers, a naturally occurring proanthocyanidin (PA) obtained from grape seeds was selected to fix biological tissues. The cytotoxicity and crosslinking rate, reflected by the in vitro and in vivo degradation of fixed matrices has been studied. The shrinkage temperature of the fixed bovine pericardium increased from 66 to 86 degrees C. A cytotoxicity assay using fibroblast cultures revealed that PA is approximately 120 times less toxic than glutaraldehyde (GA), a currently used tissue stabilizer. In vitro degradation studies showed that fixed tissue was resistant to digestion by bacterial collagenase. Crosslinks between PA and tissues can be stabilized by decreasing the dielectric constant of the solution during storage. After subcutaneous implantation for periods ranging between 3 and 6 weeks, we found no apparent degradation of the GA- or PA-fixed tissues, whereas fresh tissue controls rapidly disintegrated. Beyond 6 weeks PA crosslinks began to degrade. More fibroblasts migrated and proliferated inside the PA-fixed implants compared with GA counterparts. Tissues crosslinked with PA manifested an enhanced collagen expression and deposition and did not calcify after implantation. GA, on the other hand, even after thorough rinsing continued to be cytotoxic, inhibited collagen synthesis and encouraged dystrophic calcification. Collagen matrices crosslinked with PA are expected to be of value in the design of matrices that will encourage cell ingrowth and proliferation, which are temporary in nature, and that are intended to regenerate or replace missing tissues, which can delay the biogradation of collagen. As such they should be of significant value in the emerging field of tissue engineering. 相似文献
100.
Conclusions NT antibodies to LI virus were found in the sera of Swedish cows from many parts of the country although only exceptionally in the north. The prevalence of positive specimens increased markedly towards the southeast. This geographic distribution apparently fits well with the occurrence of ticks in the country. An analysis, now in progress, of RSSE-LI antibodies in human cases of meningoencephalomyelitis seems to indicate a closely similar distribution of the human RSSE infections. It is thus obvious that the screening of cow sera for LI antibodies provides reliable information as to endemic regions of RSSE-LI-like viruses. There was nothing to suggest that nonspecific reactions occurred or impaired the results; in fact the very uneven geographic distribution of positive specimens, of high as well as low titers, should argue for specificity of the reaction.Aided by a grant from the Swedish National Association against Poliomyelitis.The skilful technical assistance of MissSiri Austrin, MissIngrid Lövhvist, MissBrita Gustafson and Mr.Nils Lundh is gratefully acknowledged. 相似文献