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991.
The dried ethanol extract of the whole plant of Cuscuta campestris Yuncker was studied for its analgesic, antipyretic, antiinflammatory as well as CNS-depressant activities. The extract was given orally at doses of 50 and 100 mg/kg. A significant protection against the p -benzoquinone-induced writhing response in mice was observed. A marked lowering of the body temperature of both hyperthermic as well as normothermic mice was produced. Therefore, the extract possesses a hypothermic rather than an antipyretic effect. A marked inhibition of the carrageenan-induced rat hind paw oedema was also obtained. Regarding its CNS action, the extract produced a decrease in the motor activity of mice placed on a rotarod. In the conditioned avoidance reaction test the percentage of failure to avoid electric shock was shown to be increased after administration of the extract without any effect on the escape behaviour of the trained rats. Therefore, the CNS-depressant activity of the extract seems to be due to a tranquillizing effect. It could be concluded that the extract possesses analgesic, hypothermic, antiinflammatory as well as CNS-depressant activities.  相似文献   
992.
We detected Rickettsia africae, the agent of African tick-bite fever (ATBF), by amplification of fragments of gltA, ompA, and ompB genes from 3 specimens of Amblyomma loculosum ticks collected from humans and birds in New Caledonia. Clinicians who treat persons in this region should be on alert for ATBF.  相似文献   
993.
The reaction of o-phenylene diamine and ethyl oxamate is reinvestigated and led to 3-aminoquinoxalin-2(1H)-one rather than benzimidazole-2-carboxamide as was previously reported. The structure of the obtained quinoxaline has been confirmed by X-ray. The anti-tumor activity of synthesized quinoxalines 1-21 has been evaluated by studying their possible inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Among the studied compounds 1-21, compounds 12, 8, 13, 18, 17 and 19, respectively, demonstrated strong inhibitory effects on the EBV-EA activation without showing any cytotoxicity and their effects being stronger than that of a representative control, oleanolic acid. Furthermore, compound 12 exhibited a remarkable inhibitory effect on skin tumor promotion in an in vivo two-stage mouse skin carcinogenesis test using 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter. The result of the present investigation indicated that compound 12 might be valuable as a potent cancer chemopreventive agent. Moreover, the molecular docking into PTK (PDB: 1t46) has been done for lead optimization of the aforementioned compounds as potential PTK inhibitors.  相似文献   
994.
Sixteen polycyclic aromatic hydrocarbons (PAHs) were evaluated for the ability to activate aryl hydrocarbon (Ah) receptor signaling in a yeast-based bioassay. Individual PAHs were classified as inactive or as weakly, moderately, or strongly active based on induction of human Ah receptor signaling. Indeno[1,2,3-cd]pyrene, chrysene, benzo[a]anthracene, benzo[a]pyrene, benzo[j]fluoranthene, and benzo[k]fluoranthene were the most potent activators of human Ah receptor signaling. Various mixtures of PAHs had additive or synergistic effects in the bioassay. Environmental samples from the New Orleans (Louisiana, USA) and Detroit (Michigan, USA) areas that were previously analyzed for PAH composition and quantity were tested in this bioassay. Weak but statistically significant relationships were found when the analytically measured levels of PAHs were correlated with sample dilutions that gave 25% effective concentration signaling levels in the Ah receptor assay. We conclude that this Ah receptor signaling assay may be useful for preliminary biomonitoring of samples for PAHs and other Ah receptor ligands.  相似文献   
995.

Introduction

Previous studies have reported a role for human cytomegalovirus (HCMV) in breast carcinogenesis. We sought to assess the role of HCMV infection in the development and/or progression of breast cancer (BC) among Egyptian patients.

Patients and Methods

The study included 61 patients with BC cases. Of these 61 patients, 40 had been assessed for HCMV in the blood, BC tissue samples, and adjacent non-neoplastic tissue samples, and 21 had been assessed for HCMV in the tissue only. Tissue samples from 20 patients with fibroadenoma (FA) were also included. As a control group, 41 blood samples obtained from healthy women with no history of cancer were used as a blood control group. HCMV was assessed using enzyme-linked immunosorbent assay, real-time polymerase chain reaction (PCR), and immunohistochemistry (IHC).

Results

A significant difference was found in the index value for the anti-CMV IgG antibodies between the BC patients and the control group (P = .001). Using real-time PCR, HCMV DNA was detected in 11 of 61 BC tissues (18%) compared with 1 of 20 FA tissues (5%). HCMV DNA was present in 8 of the 40 plasma samples (20%). Regarding the viral proteins, 21 of 61 samples (34.4%) were positive for early/immediate early (E/IE) and 49 (80.3%) were positive for PP65 expression by IHC. The concordance between the results obtained by the different assays was low. CMVPP65 expression was significantly associated with E/IE protein expression in the malignant and FA groups (P < .001).

Conclusion

The presence of CMV proteins and DNA in BC tissues suggests a role for this virus. However, the basic criteria to support a causal association of HCMV with BC were not fulfilled.  相似文献   
996.
This study was carried out to assess the efficacy, safety and tolerability of fluvastatin as monotherapy in the treatment of primary hypercholesterolemia. This multicenter study started with 467 patients but only 315 subjects completed 12 weeks treatment. Patients followed a standard lipid-lowering diet for 3 weeks before entering and throughout the study. Every patient received fluvastatin 20 mg once daily with the evening meal for the first 6 weeks, from week 7 to week 12 the daily dose was changed to one capsule 40 mg daily in the evening. Results showed that the mean percent changes in lipid parameters between baseline and endpoint was as follows: LDL-C (-32.7%); total cholesterol (-29.42%), triglycerides (-19.7%) and HDL-C (16.6%). Meanwhile, the mean percent increase in liver enzymes between baseline and endpoint was 17.2% for ASAT and 20.3% for ALAT, respectively, but the mean values of both enzymes at the endpoint were within normal range. The most frequent side effects being gastrointestinal (4.3%) including dyspepsia, nausea, flatulence and diarrhea. In conclusion, fluvastatin as monotherapy in the treatment of hypercholesterolemia among Saudis was found to be safe, well tolerated and produced a significant improvement in the overall lipid parameters.  相似文献   
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