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81.
By human intestinal bacteria, saikosaponin c was transformed to four metabolites, prosaikogenin E1 (E1) prosaikogenin E2 (E2), prosaikogenin E3 (E3) and saikogenin E. Metabolic time course of saikosaponin c was as follows; in early time, saikosaponin c was converted to E1 and E2, and then these were transformed to saikogenin E via E3. Also, this metabolic pathway was similar to the metabolism of saikosaponin c by rat intestinal bacteria.Bacteroides JY-6 andBacteroides YK-4, the bacteria isolated from human intestinal bacteria, could transform saiko-saponin c to E via E1 (or E2) and E3. However, these bacteria were not able to directly transform E1 and E2 to saikogenin E. Naringin was mainly transformed to naringenin by human intestinal bacteria. The minor metabolic pathway transformed naringin to naringenin via prunin. By JY-6 or YK-4, naringin was metabolized to naringenin only via prunin. 相似文献
82.
Twenty seven plant extracts were selected on the basis of ancient literature search for rheumatoid arthritis or similar syndrome. Methanol extract of each plant was prepared and administered orally to rats everyday at a dose of 200 mg/kg/day. Experimental arthritis was induced by subplantar injection of heat-killedMycobacterium butyricum to right hind paw of rats. This treatment provoked swelling of the treated paw in two phases, acute primary swelling and secondary arthritic swelling. An inhibition of secondary swelling was considered to be antiarthritic activity. Several plant methanol extracts such asAkebia quinata (caulis),Ephedra sinica (herba) andSophorae subprostrata (radix) were found to show significant inhibitory activity against secondary swelling at the dose tested. Our results strongly suggested an antiarthritic potential of these plant extracts. 相似文献
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Climate, traffic-related air pollutants, and asthma prevalence in middle-school children in taiwan 总被引:7,自引:0,他引:7 下载免费PDF全文
Guo YL Lin YC Sung FC Huang SL Ko YC Lai JS Su HJ Shaw CK Lin RS Dockery DW 《Environmental health perspectives》1999,107(12):1001-1006
This study compared the prevalence of asthma with climate and air pollutant data to determine the relationship between asthma prevalence and these factors. We conducted a nationwide survey of respiratory illness and symptoms in middle-school students in Taiwan. Lifetime prevalences of physician-diagnosed asthma and of typical symptoms of asthma were compared to air monitoring station data for temperature, relative humidity, sulfur dioxide, nitrogen oxides, ozone, carbon monoxide, and particulate matter with aerodynamic diameter [less than/equal to] 10 microm (PM(10)). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Asthma prevalence rates adjusted for age, history of atopic eczema, and parental education were associated with nonsummer (June-August) temperature, winter (January-March) humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, for both girls and boys. Nonsummer temperature, winter humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, were positively associated with the prevalence of asthma in middle-school students in Taiwan. 相似文献
86.
OBJECTIVE: Comparison of the healing process in open osteotomy and closed fracture models that were used to study fracture healing. DESIGN: Randomized, prospective study in experimental animals, with a recovery duration of two and four weeks. SETTING: Unrestricted cage activity with weight bearing as tolerated. ANIMALS: Thirty-four skeletally mature, female New Zealand White rabbits. INTERVENTIONS: Closed fractures and open osteotomies of the tibial diaphysis were reduced and immobilized with four-pin, double-bar external fixators. MAIN OUTCOME MEASUREMENTS: Callus circumference was measured with a tape measure, bridging callus was assessed on biplane radiographs and evaluated histologically, and torsional stiffness and maximum torque were measured. RESULTS: Periosteum damage was more severe and hematoma formation was smaller in the osteotomy model, resulting in a delay in biological healing and restoration of the biomechanical properties. CONCLUSIONS: Investigators should consider the difference between the closed fracture and open osteotomy models when selecting an animal model to investigate fracture healing. 相似文献
87.
The role of genetics in Parkinson's disease (PD), previously controversial, is now supported by several studies. A major breakthrough has been the discovery of a single gene defect in familial Parkinson's disease. A single base pair change at position 209 from G to A (G209A) in the fourth exon of the alpha-synuclein gene has been identified in cases of familial PD. We looked for this mutation in 65 cases of sporadic PD in Taiwan Chinese patients but found none of these patients with this mutation. We conclude that mutation of G209A in the alpha-synuclein gene plays no role in sporadic PD among Taiwan Chinese. 相似文献
88.
Hepatitis C virus (HCV) nonstructural (NS) proteins appeared to be important targets for HCV vaccine development, since NS-specific T-helper-cell responses are associated with clearance from acute HCV infection. In this report, we have constructed a plasmid, pTV-NS345, that encodes the HCV NS3, NS4 and NS5 proteins (NS345) and a bicistronic plasmid, PTV-NS345/GMCSF, in which the HCV NS345 polyprotein and GMCSF are translated independently. Intramuscular inoculation with pTV-NS345 plasmid DNA into the Buffalo rats generated both antibody and T-cell proliferative responses to each NS protein. The expression of GMCSF, together with HCV NS345 proteins, appeared to significantly increase T-cell proliferative responses. In particular, the inoculation of a bicistronic plasmid generated higher T-cell proliferative responses to each NS protein than did the coinjection of two separate plasmids, pTV-NS345 and pTV-GMCSF. These results demonstrate that the codelivery of GMCSF augmented HCV NS345-specific cellular immunity and that the intensity of the immunity was differed depending on how GMCSF gene is codelivered. 相似文献
89.
A series of 4-amino Capsaicin analogs 15, 17 and 19 were prepared to investigate the bioisosteric effect of 4-amino group, and all these compounds exhibited moderate or weak potency from their analgesic test. From our previous results and others, 4-hydroxyl group as well as 3-methoxy substituent could be crucial for high analgesic activity. This biological result also shows that the activity is sensitive to alkyl chain length in hydrophobic region and the phenylacetic amides 19 are more active than the corresponding urea derivatives 17. 相似文献
90.
Hak Cheol Kwon Byeong Gon Lee Seung Hee Kim Chil Mann Jung Sung Youl Hong Jeung Whan Han Hyang Woo Lee Ok Pyo Zee Kang Ro Lee 《Archives of pharmacal research》1999,22(4):410-413
In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two beta-carboline alkaloids, 4-methoxy-1-vinyl-beta-carboline (1) and 4,8-dimethoxy-l-vinyl-beta-carboline (2) have been isolated from the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed marked inhibitory activity of iNOS on LPS- and interferon-gamma-stimulated RAW 264.7 cells. 相似文献