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1.
植物营养活力素对小鼠生长及耐受能力的影响 总被引:3,自引:3,他引:0
以不同剂量的植物营养活力素(PVN)喂饲小鼠,对小鼠的体重增长、耐寒、耐热、耐力等进行了观测。结果:用药后实验小鼠的体重和胸脾系数明显增加;耐寒、耐热及持续游泳时间明显延长。表明PVN可明显提高小鼠的体重增长和对应激的耐受能力,提示其营养作用不仅适用于植物,而且适用于动物。 相似文献
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12种中草药的乙醇提取液对印鼠客蚤的毒效研究 总被引:4,自引:1,他引:3
目的:探讨中草药灭蚤的可行性。方法:用乙醇提出12种中草药的可溶成分,以瓶膜法测定其对印鼠客蚤的毒力。结果:在0.5g/ml(生药)的浓度下,10种中草药对印鼠客蚤有速效击倒作用,其中鸡血藤、巴豆仁、除虫菊花的10min击倒率大于50%;5种中草药的KD_(50)小于15min,比2%DDVP为优;巴豆仁接触30min恢复24h死亡率为70%。结论:除虫菊花、黎芦、鸡血藤、巴豆仁、贯众用于杀蚤有一定价值。 相似文献
4.
目的:通过观察银杏叶提取物(EGb)对交感神经节细胞生物电的影响,为进一步探讨EGb调节肠系膜下神经节(IMG)支配的包括远端结肠在内的内脏功能活动的作用机制提供依据。方法:采用细胞内生物电记录技术记录体外IMG电位。结果:在敏感细胞,EGb761(35~350mg/L)可使71.0%的肠系膜下神经节细胞产生膜去极化反应,且在一定范围内呈现剂量效应关系;19.4%的细胞超极化;9.7%的细胞出现先超极化后去极化的双相反应。去极化反应的细胞其膜电阻有降低、增大和不变等多种表现。此去极化反应可被低钙.高镁克氏液部分阻断,但不为胆碱和肾上腺素受体阻断剂所阻断。还发现EGb761可抑制外源性5-HT引起的去极化电位。结论:EGb761对IMG细胞可能通过非胆碱能、非肾上腺素能通路产生易化作用;其机制可能与影响其他递质的释放有关。 相似文献
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色甘酸钠混悬气雾剂与茶碱缓释胶囊治疗中度哮喘的比较 总被引:1,自引:1,他引:0
84例中度哮喘病人分成2组。色甘酸钠组(男性23例,女性20例,年龄26±s8a)吸入色甘酸钠混悬气雾剂10.5mg,tid。茶碱缓释胶囊组(男性22例,女性19例,年龄27±8a)口服0.25g。bid。2组均连续观察3mo。结果:色甘酸钠在减轻病人慢性症状、改善肺功能和降低气道高反应性等方面优于茶碱缓释胶囊,(P<0.01)。而后药仅可缓解近期症状。 相似文献
7.
Manis PB Molitor SC Wu H 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,153(4):443-451
During intracellular recordings in rodent brainstem slice preparations, dorsal cochlear nucleus (DCN) pyramidal cells (PCs) exhibit characteristic discharge patterns to depolarizing current injection that depend on the membrane potential from which the responses are evoked. When depolarized from hyperpolarized potentials, PCs can respond with a short-latency action potential followed by a long silent interval (pauser) or a train of action potentials with a long latency (buildup). During the silent intervals in a pauser or a buildup response, the membrane potential slowly depolarizes towards spike threshold, often exhibiting distinct voltage oscillations of 1–2 mV before the first spike. The subthreshold voltage oscillations were investigated using whole cell recordings from DCN PCs in rat pup (P10–14) brainstem slices. The oscillations were unaffected by excitatory and inhibitory neurotransmitter antagonists, and were not temporally locked to the onset of the depolarization. The oscillations typically became larger as spike threshold was approached, and had a characteristic frequency between 40 and 100 Hz. In the presence of tetrodotoxin (TTX, 500 nM), the oscillations were significantly suppressed, and could not be evoked at any voltage below or above spike threshold. The oscillations were not blocked by phenytoin or Cd2+, but they were affected by prior activity in the neuron for approximately 1 s. We conclude that voltage-gated Na+ channels are required to generate membrane oscillations during the buildup phase. We suggest that the subthreshold oscillations play a role in controlling spike timing in PCs when the membrane potential slowly approaches, or hovers near, spike threshold. 相似文献
8.
The IgG subclasses of immunoglobulin for intravenous injection (IVIg) were investigated after various different types of treatment.
The level of IgG2 was relatively low in preparations treated with pepsin, but by changing the clone producing anti-IgG2 antibody,
the level approached that of normal human serum. Though undetectable in sulfonated immunoglobulin preparations, IgG3 was detected
after reoxidation. When determining the IgG subclasses of IVIg, it must be kept in mind that the apparent value may subsequently
become lower due to the depressed reaction of the antibody. 相似文献
9.
Hortense Dodo Damien Marsic Monique Callender Ernst Cebert Olga Viquez 《Food and Agricultural Immunology》2002,14(2):147-154
Peanut is one of the most allergenic foods and reports of accidental ingestion of peanuts in unsuspected food are increasing. No information is available on the allergen content of peanut germplasm grown commercially and used in the food and confectionery industry. The objectives of this study were: (1) to determine the allergen contents of 34 peanut introductions (PI); and (2) to identify naturally occurring allergen-free and/or low or hypoallergenic peanuts germplasm. A basic ELISA protocol was utilized to detect the presence of antigens in the peanut lines using a pool of human sera from patients with documented history of peanut allergy. Two naturally occurring low, or hypo-allergenic germplasm were identified as PI 261942 and PI 338386. Both are Valencia market types with total allergen content significantly lower (P ≤0.05) than that of PI 119880 (0.550), PI 119876 (0.415) and PI 118991 (0.410) three Valencia market types and PI 262111 (0.485), a Virginia market type. No allergen-free PI was found. Allergen content of peanut lines from Bolivia and Paraguay were significantly (P ≤0.05) different to those from Venezuela. No significant difference was observed in the allergen content of the four market types. 相似文献
10.
Chekhonin VP Lebedev SV Dmitrieva TB Blinov DV Lazarenko IP Savchenko EA Volodin NN 《Bulletin of experimental biology and medicine》2002,133(6):609-613
Cell preparations of ventral mesencephalon obtained from 8-, 14-, and 16-17-day rat embryos were stereotactically transplanted to homologous rats with 6-hydroxydopamine-induced hemiparkinsonism. Automated analysis of apomorphine-induced motor asymmetry for 3 months after neurotransplantation revealed higher efficacy of cell preparations from 8- and lower from 16-17-day-old embryos. These data correlated with histomorphological findigs, in particular, with the size of grafts, glial reaction, and the number of dopaminergic neurons in the grafts. 相似文献