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71.
72.
Chi-Man Koon Subiyanto Fong Elaine Wat Yan-Ping Wang David Wing-Shing Cheung Clara Bik-San Lau Ping-Chung Leung Han-Dong Sun Qin-Shi Zhao Kwok-Pui Fung 《Journal of ethnopharmacology》2014
Ethnopharmacological relevance
Erigerontis Herba is widely used as a traditional Chinese medicine and is commonly used for neuroprotection and vascular protection.Aim of study
In this study, the vasodilator effects of Erigerontis Herba (DZXX) were investigated using rat isolated aorta rings.Material and method
The involvement of endothelium in the vasorelaxation was studied by comparing response of endothelium-intact and endothelium-denuded aorta rings which precontracted with U46619. The involvement of K+ channels was studied by pretreatment of the aorta rings with various K+ channel inhibitors. The involvement of Ca2+ channel was studied by incubating aorta rings with Ca2+-free solution, primed with U46619 prior to elicit contraction by addition of Ca2+ solution.Results
DZXX (0.2–2 mg/ml) induced a concentration-dependent relaxation on U44619-precontracted aorta rings with EC50 of 0.354±0.036 mg/ml. Removal of endothelium or pretreatment with a BKCa inhibitor iberiotoxin, KIR inhibitor barium chloride or Kv inhibitor 4-aminopyridine produced no effect on the DZXX-induced vasorelaxation. However, pretreatment with a KATP inhibitor glibenclamide or a non-selective K+ channel inhibitor tetraethylammonium produced significant inhibition on the DZXX-induced vasorelaxation by 29.9% and 21.3%, respectively. Pretreatment with DZXX (0.4, 1.2 and 2 mg/ml) produced a concentration-dependent inhibition on Ca2+-induced vasoconstriction.Conclusions
These results suggest that the vasodilator effect of DZXX was endothelium-independent, mediated by decreasing the influx of Ca2+ by calcium channel inhibition and increasing the influx of K+ by opening of a KATP channel. 相似文献73.
74.
回春液补肾助阳药效学的实验研究 总被引:2,自引:0,他引:2
回春液由人参、鹿茸、貂鞭等名贵中药组成。有补肾助阳,填精益气等功效。药效学研究证实,该药有促进幼鼠发育及增加去势大鼠前列腺——精液囊的重量,亦显著增加小鼠血红蛋白的含量,表明回春液有雄性激素样作用。 相似文献
75.
Girardet RG McClain N Lahoti S Cheung K Hartwell B McNeese M 《The Pediatric infectious disease journal》2001,20(2):144-147
BACKGROUND: The urine-based ligase chain reaction (LCR) assay for Chlamydia trachomatis and Neisseria gonorrhoeae is an attractive alternative to culture because of the relative ease with which specimens may be collected, transported and processed. In addition LCR offers superior sensitivity while maintaining high specificity when compared with culture in various studies of adolescents and adults. A study comparing LCR to culture has not been published concerning children. METHODS: We conducted a prospective, comparison trial of the urine-based LCR test for Chlamydia trachomatis and Neisseria gonorrhoeae as compared with culture among children at a specialized referral center for evaluation for alleged sexual assault. Of the 1,010 children presenting to the center during the study period, 164 met the study requirements for risk of a sexually transmissible disease and collection of both culture and urine LCR specimens. RESULTS: Eight specimens tested positive by both methods for C. trachomatis. Another 10 specimens tested positive for C. trachomatis by LCR but were negative by culture. No patient with a negative LCR for C. trachomatis had a positive culture. For N. gonorrhoeae 2 specimens tested positive by both methods, and 3 specimens tested positive by LCR but negative by culture. No patient with a negative LCR for N. gonorrhoeae had a positive culture. CONCLUSIONS: The low prevalence of disease in the study population precluded statistical analysis. LCR may prove to be as specific and more sensitive than culture for the detection of C. trachomatis and N. gonorrhoeae in children. Further studies are needed. 相似文献
76.
Tatad AM Nesin M Peoples J Cheung S Lin H Sison C Perlman J Cunningham-Rundles S 《Neonatology》2008,94(1):8-15
BACKGROUND: Neonatal susceptibility to bacterial infection is associated with an immature immune system, but the role of different bacterial antigens in specific responses is largely unknown. OBJECTIVE: To evaluate differences in intracellular cytokine response to physiologically relevant bacterial antigens in term and preterm infants as compared with adults. METHODS: Cord blood samples from preterm and term neonates and adult peripheral blood samples were cultured ex vivo with and without whole heat-killed bacteria. Intracellular leukocyte production of interleukin (IL)-6, IL-10, IL-12, and IL-8 responses was assessed by flow cytometry. RESULTS: Monocytes were the primary producers of all mediators. Escherichia coli was the most potent stimulant. Lactobacillus plantarum 299v activated fewer monocytes as compared with E. coli for all responses (p < 0.05), except for IL-12 in term neonates. IL-6 response to Staphylococcus epidermidis was lower in both groups of neonates as compared with adults (p = 0.023 and p = 0.001). IL-8 response to S. epidermidis was lower in term as compared with preterm neonates and adults (p = 0.003). IL-10 response to group B streptococci was lower in term neonates as compared with adults and higher in preterm as compared with term neonates (p = 0.015). CONCLUSIONS: Monocytes from term neonates compared to preterm neonates show a downregulated anti-inflammatory response to specific bacteria. High neonatal response to pathogenic E. coli in the preterm infant could cause uncontrolled inflammatory response, while lower IL-6 response to S. epidermidis in neonates may indicate a basis for vulnerability to S. epidermidis infection. 相似文献
77.
78.
79.
Immunomodulatory and anti-SARS activities of Houttuynia cordata 总被引:1,自引:0,他引:1
Lau KM Lee KM Koon CM Cheung CS Lau CP Ho HM Lee MY Au SW Cheng CH Lau CB Tsui SK Wan DC Waye MM Wong KB Wong CK Lam CW Leung PC Fung KP 《Journal of ethnopharmacology》2008,118(1):79-85
BACKGROUND: Severe acute respiratory syndrome (SARS) is a life-threatening form of pneumonia caused by SARS coronavirus (SARS-CoV). From late 2002 to mid 2003, it infected more than 8000 people worldwide, of which a majority of cases were found in China. Owing to the absence of definitive therapeutic Western medicines, Houttuynia cordata Thunb. (Saururaceae)(HC) was shortlisted by Chinese scientists to tackle SARS problem as it is conventionally used to treat pneumonia. AIM OF THE STUDY: The present study aimed to explore the SARS-preventing mechanisms of HC in the immunological and anti-viral aspects. RESULTS: Results showed that HC water extract could stimulate the proliferation of mouse splenic lymphocytes significantly and dose-dependently. By flow cytometry, it was revealed that HC increased the proportion of CD4(+) and CD8(+) T cells. Moreover, it caused a significant increase in the secretion of IL-2 and IL-10 by mouse splenic lymphocytes. In the anti-viral aspect, HC exhibited significant inhibitory effects on SARS-CoV 3C-like protease (3CL(pro)) and RNA-dependent RNA polymerase (RdRp). On the other hand, oral acute toxicity test demonstrated that HC was non-toxic to laboratory animals following oral administration at 16 g/kg. CONCLUSION: The results of this study provided scientific data to support the efficient and safe use of HC to combat SARS. 相似文献
80.
BACKGROUND: Embedded fetal bone after surgical termination of midtrimester pregnancy is a recognized complication. Most cases occur in the uterine cavity; however, this case demonstrates that a cervicovaginal fistula can be caused by embedment of bone in the cervical canal. CASE: A 19-year-old girl presented with persistent smelly vaginal discharge 4 years after surgical pregnancy termination. On examination she had a cervicovaginal fistula with embedded fetal bone that was subsequently removed surgically. CONCLUSION: Cervicovaginal fistula can be a complication of surgical termination of midtrimester pregnancy as fetal bones can become embedded in the cervical canal during removal. 相似文献