ABSTRACT
Spinal cord stimulation (SCS)-induced analgesia was characterized, and its underlying mechanisms were examined in a spared nerve injury model of neuropathic pain in rats. The analgesic effect of SCS with moderate mechanical hypersensitivity was increased with increasing stimulation intensity between the 20% and 80% motor thresholds. Various frequencies (2, 15, 50, 100, 10000 Hz, and 2/100 Hz dense-dispersed) of SCS were similarly effective. SCS-induced analgesia was maintained without tolerance within 24 h of continuous stimulation. SCS at 2 Hz significantly increased methionine enkephalin content in the cerebrospinal fluid. The analgesic effect of 2 Hz was abolished by μ or κ opioid receptor antagonist. The effect of 100 Hz was prevented by a κ antagonist, and that of 10 kHz was blocked by any of the μ, δ, or κ receptor antagonists, suggesting that the analgesic effect of SCS at different frequencies is mediated by different endorphins and opioid receptors.
Subject(s)
Animals , Rats , Analgesics , Narcotic Antagonists/pharmacology , Neuralgia/therapy , Opioid Peptides , Receptors, Opioid/physiology , Receptors, Opioid, kappa , Spinal Cord , Spinal Cord StimulationABSTRACT
OBJECTIVE: To explore the serological infection rate of hepatitis B virus (HBV) in general population aged over one year old in Beijing and to provide information for control and prevention of the disease. METHODS: A multistage randomized cluster sampling was carried out in general population of Beijing, aged over one year old. Every study subject's hepatitis B immunization history and main risk factors were investigated through questionnaire. Venous blood samples were collected and then tested for five hepatitis B serological antigens and antibodies by means of Abbott Microparticle Enzyme Immunoassy method. RESULTS: The prevalence rates of HBsAg, anti-HBs, anti-HBc and total HBV infection rate were 3.49% (95% CI:2.99-3.99), 37.79% (95% CI: 36.46-39.12), 35.04% (95% CI: 33.72-36.35) and 35.09% (33.78-36.40) respectively. The age standardized rates were 3.02% ,42.47% ,26.86% and 26.90% respectively. CONCLUSION: Achievement in hepatitis B control and prevention was made in Beijing since the prevalence rate of hepatitis B surface antigen had been below 1% for children aged less than 5 years old. As for the general population, the prevalence rate of hepatitis B surface antigen had reduced to
Subject(s)
Hepatitis B/blood , Hepatitis B/epidemiology , Adolescent , Adult , Age Distribution , Child , Child, Preschool , China/epidemiology , Hepatitis B/immunology , Hepatitis B/prevention & control , Hepatitis B Antibodies/immunology , Hepatitis B Surface Antigens/immunology , Hepatitis B Vaccines/therapeutic use , Humans , Infant , Middle Aged , Young AdultSubject(s)
Hepatitis B Vaccines , Hepatitis B/prevention & control , Vaccination , Adolescent , Adult , Child , Child, Preschool , China/epidemiology , Hepatitis B/epidemiology , Hepatitis B Vaccines/immunology , Humans , Immunization Schedule , Infant , Middle Aged , Prevalence , Vaccines, Synthetic/immunologyABSTRACT
OBJECTIVE: To evaluating the epidemiological effect after hepatitis B immunization among youngsters in Beijing. METHODS: A multistage sampling method was used for data collection from immunization cards, reports on field epidemiological survey on hepatitis B virus (HBV) immunization of youngsters and the analysis of infectious diseases. HBsAg, anti-HBs and anti-HBc levels were detected by solid phase radioimmunoassays (SPRIA). RESULTS: The average incidence rates of hepatitis B in 10 - 19 years-olds prior to HBV immunization was 12.11-16.89/100 000, while declined to 1.78-10.95/100 000 (chi(2) = 10.71 - 60.45, P < 0.01). HBsAg carrying rate of the youngsters decreased from 6.34% to 1.37% (80.00%) after vaccination (chi(2) = 14.16, P < 0.01). CONCLUSION: Hepatitis B vaccination among youngsters is an effective measure for the prevention and control of hepatitis B virus infection.
Subject(s)
Hepatitis B Vaccines , Hepatitis B/prevention & control , Vaccination , Adolescent , Child , China/epidemiology , Hepatitis B/epidemiology , Hepatitis B Vaccines/immunology , Humans , Immunization Schedule , Prevalence , Vaccines, Synthetic/immunologyABSTRACT
OBJECTIVE: To evaluate the epidemiological effect of hepatitis B immunization among newborn babies in Beijing. METHODS: A multistage sampling method was used for the collection of immunization cards, field epidemiological survey on hepatitis B virus (HBV) immunization of children, analysis of infectious disease reports. HBsAg, anti-HBs and anti-HBc levels were detected by solid phase radioimmunoassays (SPRIA). RESULTS: The incidence of hepatitis B in children of 0 to 14 years at the beginning of HBV immunization was 18.59 to 20.52/100,000, and declined to 0.39 to 2.38/100,000 in 2000 (chi2 = 58.26, P < 0.01). The HBsAg carrying rate of the children decreased from 2.82% to 0.60%, about 80.00% after vaccination (chi2 = 10.75, P < 0.01). CONCLUSION: Hepatitis B vaccination of newborn babies is an effective measure for prevention and control of hepatitis B virus infection.
