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31.
贯众提取液对革兰氏阳性球菌的抑菌作用 总被引:6,自引:0,他引:6
目的:了解贯众(Dryopteris crossirhizomz)不同提取液对革兰氏阳性球菌的抑菌作用。方法:分别用水以及3种不同pH值的70%乙醇为溶媒提取贯众干品以制备贯众提取液,利用打孔法和试管稀释法测定提取液对13种微生物的抑制效果。结果:每1ml含生药1g的贯众醇提液、水提液对革兰氏阳性菌有较强的抑制作用,尤其是革兰氏阳性球菌如金黄色葡萄球菌和甲型溶血性链球菌等。对革兰氏阴性菌和真菌的抑制作用较弱,但对普通变形杆菌则有较强的抑制作用。不同pH值的抽提溶剂对药物的有效抑菌成份的提出效果不同,抽提溶剂pH越小,有效成份的提出效果越好。结论:贯众醇提液、水提液对革兰氏阳性菌有较强的抑制作用,尤其是对革兰氏阳性球菌,而对革兰氏阴性菌和真菌的抑制作用则较弱。贯众的抗菌成份易溶于水,抽提效果随pH减小而增加。 相似文献
32.
Ivermectin for the chemotherapy of bancroftian filariasis: a meta-analysis of the effect of single treatment 总被引:4,自引:4,他引:0
Wu-chun Cao Catharina P. B. Van der Ploeg Anton P. Plaisier I. J. Sivera van der Sluijs J. Dik F. Habbema 《Tropical medicine & international health : TM & IH》1997,2(4):393-403
Summary The efficacy and safety of ivermectin in the treatment of filariasis due to Wuchereria bancrofti was assessed by a meta-analysis of the results from 15 published clinical trials. Seven hundred and forty-eight microfilaraemic patients were enrolled in 7 dose-finding and 8 comparative studies. Administered as a single dose, ivermectin induced nearly complete clearance of microfilariae from the blood from the first day to 30 days post-treatment, followed by gradual recurrence of microfilaraemia and increase in its intensity. Higher doses of ivermectin showed greater clearance effects and maintained lower microfilaraemia levels for a longer time. The adverse reactions caused by the drug were flu-like, transient, generally mild and well tolerated by patients. The frequency and intensity of adverse reactions were strongly associated with pretreatment microfilaria counts in the blood, but independent of dose. The findings of the meta-analysis suggest that ivermectin given at a single annual dose of 200 μg/kg body weight or higher, whether or not in combination with DEC, has great potential for therapeutic strategies to control bancroftian filariasis. 相似文献
33.
江苏省肾综合征出血热单价灭活疫苗中期免疫效果观察 总被引:5,自引:2,他引:3
观察HFRS单价灭活疫苗中期免疫效果。方法:采用IFAT法及MCPENT法检测荧光抗体及中和抗体。结果:3个试区加强接种人数分别为4052、4407和6354人。加强后,Ⅰ型苗荧光抗体阳性率为72.73%,GMT为14.14;中和抗体阳性率为54.55%,GMT为6.67。D型苗荧光抗体阳性率为75.00%,GMT为11.85;中和抗体阳性率为60%,GMT为9.44。加强后1年,Ⅰ型苗年均保护率为65.52%,Ⅱ型苗则为94.24%。同期,Ⅰ型苗荧光抗体阳性率维持在40%,中和抗体维持在35.00%;Ⅱ型苗荧光抗体阳性率降至10.34%,中和抗体维持在53.85%。结论:两型疫苗均有较好的中期防病效果。 相似文献
34.
35.
In many animal studies, acute treatment with the novel anxiolytic agent buspirone exhibits only minimal anxiolytic efficacy (i.e., increases in punished responding) when compared to benzodiazepines and barbiturates. The present studies examined the effects of acute pre-test challenges with buspirone in subjects receiving chronic post-test buspirone or saline treatments. Chronic post-test treatment with buspirone (4 mg/kg/day for 4 weeks, followed by 8 mg/kg/day for 12 weeks) did not significantly affect CSD behavior. Consistent with previous reports, acute pre-test administration of buspirone (0.125–2 mg/kg, IP) to subjects receiving chronic post-test saline treatment resulted in only a modest anti-conflict effect in the CSD paradigm (approximately ten shocks over control). In contrast, subjects chronically treated with buspirone exhibited a dramatically greater anti-conflict effect following acute challenge with buspirone (up to 40 shocks over control). These data are consistent with the hypothesis that the full anxiolytic efficacy of buspirone requires repeated administration. 相似文献
36.
Itoh K Naganawa Y Matsuzawa F Aikawa S Doi H Sasagasako N Yamada T Kira J Kobayashi T Pshezhetsky AV Sakuraba H 《Journal of human genetics》2002,47(1):29-37
Three novel missense mutations in the human lysosomal sialidase gene causing amino acid substitutions (P80L, W240R, and P316S)
in the coding region were identified in two Japanese sialidosis patients. One patient with a severe, congenital form of type
2 sialidosis was a compound heterozygote for 239C-to-T (P80L) and 718T-to-C (W240R). The other patient with a mild juvenile-onset
phenotype (type 1) was a homozygote for the base substitution of 946C-to-T (P316S). None of these mutant cDNA products showed
enzymatic activity toward an artificial substrate when coexpressed in galactosialidosis fibroblastic cells together with protective
protein/cathepsin A (PPCA). All mutants showed a reticular immunofluorescence distribution when coexpressed with the PPCA gene in COS-1 cells, suggesting that the gene products were retained in the endoplasmic reticulum/Golgi area or rapidly degraded
in the lysosomes. Homology modeling of the structural changes introduced by the mutations predicted that the P80L and P316S
transversions cause large conformational changes including the active site residues responsible for binding the sialic acid
carboxylate group. The W240R substitution was deduced to influence the molecular surface structure of a limited region of
the constructed models, which was also influenced by previously identified V217M and G243R transversions.
Received: Stptember 21, 2001 / Accepted: November 2, 2001 相似文献
37.
Kahn Jarl A.; von During Vidar; Sunde Arne; Sordal Terje; Molne Kare 《Human reproduction (Oxford, England)》1993,8(2):247-252
A cohort of 485 couples starting their first in-vitro fertilization(IVF) attempt between January, 1989 and February, 1991 inclusive,were followed until June 1, 1992. A total of 1086 treatmentcycles were initiated (mean 2.2, range 16). Of these,235 (21.8%) cycles were cancelled, giving a total of 851 embryoreplacements (mean 1.7, range 15). After IVF treatment,189 women have either delivered or have an ongoing pregnancyin the second or third trimester. This gives a baby take-homerate of 17.4% per started cycle and 22.2% per embryo replacement.For 91 (18.6%) of the couples, the treatment was abandoned priorto completion of the three scheduled IVF attempts and 57 (11.7%)of these had no completed IVF cycles. In the group of coupleswith reduced sperm quality, the delivery rate was significantlylower than that of the other groups. A total of 193 women hadembryos cryopreserved in at least one IVF cycle; 124 of thesewomen started a frozen embryo replacement cycle and 88 had atleast one cycle with replacement of frozen/thawed embryos, resultingin 25 deliveries/ongoing pregnancies. Due to the Norwegian lawon assisted procreation 65 (33.7%) of the women have had theirfrozen embryos thawed and discarded after 12 months of storage.The cryopreservation programme, with the limitations of theNorwegian law, gives a 5.2% increase in the baby take-home ratefor women entering the IVF programme, an increase of 13.2% inthe number of ongoing pregnancies/deliveries and an 11.6% increasein number of children/viable fetuses. A total of 214 women havedelivered or have ongoing pregnancies in the second or thirdtrimester. This represents 44.1% of the 485 women accepted forIVF treatment, irrespective of whether they were treated ornot, and 50.0% of those couples who completed at least one IVFcycle. 相似文献
38.
Mechanisms of compensation for vestibular deficits in the frog 总被引:3,自引:0,他引:3
Dr. N. Dieringer W. Precht 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1979,36(2):311-328
Summary In hemilabyrinthectomized frogs excitatory responses of central vestibular neurons to electrical stimulation of the remaining vestibular nerve were recorded extra- and intracellularly at different stages (0, 3, and 60 days) after the operation.The output pattern of ipsilateral vestibular neurons sending an axon across the midline via the vestibular commissure to the deafferented nucleus did not change postoperatively.The synaptic efficacy of these commissural axons ending on partially deafferented vestibular neurons on the lesioned side increased with time. This enhanced synaptic potency was associated with a shortening in time to peak and duration and an increase in amplitude of the evoked EPSPs. As a result most vestibular neurons were readily excited by single shock stimulation of the contralateral vestibular nerve, a finding which was rarely observed in control animals.These plastic changes are explained by the assumption of reactive synaptogenesis. The consequences of this modification for the readjustment of static and dynamic vestibular reflexes are discussed. 相似文献
39.
E. van der Veur B. S. ten Berge A. J. M. Donker J. F. May F. H. Schuurman H. Wesseling 《European journal of clinical pharmacology》1985,28(5):507-511
Summary After screening two local populations in the northern part of The Netherlands for hypertension, patients with a diastolic pressure (DP) between 95 and 120 mmHg were treated daily either with 50 mg hydrochlorothiazide or 100 mg atenolol. Non-responders were given the combination and if necessary the dose of atenolol was increased to 200 mg. Non-responders to the latter combination were randomized and treated either with 50 mg hydrochlorothiazide and labetalol or with 50 mg hydrochlorothiazide, 200 mg atenolol and prazosin. If after 1 month a DP90 mmHg had been reached the patient was reassessed after a further 3 months. If a DP>90 mmHg was found the dose of labetalol or prazosin was increased and the patient was re-examined after 1 month.This protocol was followed until the maximum dose was reached or adverse reactions prevented a further increase in dosage.During 6 months of treatment there was a further drop in systolic and diastolic blood pressures under both regimens of, respectively, 8.6 and 2.4 mmHg for labetalol, and 7.7 and 5.0 mmHg for the prazosin group. At the end of the period the average daily doses of labetalol and prazosin were 1256 mg and 4.3 mg, respectively. There was no significant difference in the average number of complaints between the labetalol and the prazosin group. 相似文献
40.
Partha Sarathi Dasgupta Twisha Lahiri 《Journal of cancer research and clinical oncology》1987,113(4):363-368
Summary The cancer chemotherapeutic efficacy of dopamine (DA) was evaluated in female strain A mice bearing transplantable Ehrlich ascites carcinoma. The results demonstrated significant inhibition of tumor growth with appreciable increase in the host survival time following DA treatment. Diminished activity of the growth-related respiratory enzyme succinate dehydrogenase along with stimulated activity of the lysosomal enzyme, -glucuronidase in DA-treated tumor cells indicated inhibition of tumor growth as well as active lysis of the tumor cells. The direct effect of this compound on tumor proliferation was demonstrated by marked inhibition of DNA synthesis. RNA synthesis was only marginally inhibited.Abbreviations DA
Dopamine
- EAC
Ehrlich ascites carcinoma
- SDH
Succinate dehydrogenase
- -Glu
-glueuronidase
- ILS
Increase of life span 相似文献