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1.
Zhang Gu-sheng章谷生 Hu Fang-yuan胡方远 Ye Qing-zhen叶庆祯 Yan Yong-tang严咏棠Immunology Laboratory Shanghai Institute of Biologicat Products Shanghai 《中华医学杂志(英文版)》1986,99(4):343-346
Neurotropin (NSP) is an extract isolated from
the skin of rabbits inoculated with vaccinia virus.
The present study examines the possible action of
NSP on the number and function of immunocompe
tent cells in mice. The experiment showed that NSP
had no effect on both T and B lymphocytes of nor-
malimmunized mouse spleen. The degree of plaque
forming cell reaction and titre of specific antibody
showed no significant differences when the NSP
treated group and controls were compared. How-
ever, NSP exhibited promotive effect on specific
antigen binding cells in the early stage of immune
responses. It was also noted that the rosette forming
capacity of human T lymphocytes in vitro was restor-
ed markedly by NSP. These results suggest that
NSP possesses certain immunostimulating activity,
particularly on the specific antigen binding cells and
human T lymphocytes. 相似文献
2.
ComparisonoftripletherapywithlansoprazoleorfamotidineforHelicobacterpyloriassociatedduodenalulcerWANGXiaoZhong,LIBinandLING... 相似文献
3.
Zhong Rui-kun钟瑞琨 Dong Yong-he董永和and Lu Dao-pei陆道培Institute of Hematology Beijing Medical University Beijing 《中华医学杂志(英文版)》1989,102(7):537-544
In order to understand the mechanism of immunosuppression caused by infusion of placental gamma globulin (PGG) in patients with renal allografts, rheumatoid arthritis, and graft – versus –host disease (GCHD) following bone marrow transplantation (BMT) ,we have examined the effect of PGG in vitro and in a model of the xenogeneic , local graft –ver- sus – host reaction (LGVHR) .PGG inhibited lymphocyte proliferation in mixed lymphocyte cultures (MLC) (P<0.005) and depressed interleukin -2 (IL-2) levels in such cultures at 72 hours (P<0.01) . In contrast phytohemagglutinin (PHA) –and pokeweed mitogen (PWM) –induced T and B lymphocyte blastogenesis was not affected by such PGG treatment .PGG treatment .PGG neither decreased the [3H] TdR pulse incorporation in unstimulated lymphocytes nor affected cell viability .Cell cycle analysis by flow cytometry showed that PGG reduced the percentage of cells in S and G2, M phases during the MLC, but did not alter cell cycling during PWM-stimulated proliferation .
An immunosuppressive effect of PGG on the LGCHR was tested in a model of intracutaneous transplantation of PGG –treat human lymphocytes into cyclophosphamide – immunosuppressed rats. Lymphoprep – separated human tonsillar lymphocytes were incubated with RPMI-1640 buffer containing:(1)PGG,4mg/ml,(2) human plasma albumin,4mg/ml,(3)mitomycin-C,25ug/ml, or (4) no additive. Cell of each preparation (3x107cells in 0.1ml) were injected intracutaneously into cyclophosphamide-treated male rats at separate abdominal locations. A fifth site received only the buffer solution. Five days after injection of cells ,each rat received [125 I]IUdR (10uCi) intraperitoneally and was killed after 5 hours. For each site of injection, the diameters of induration were measured and 125 I was counted . There was no difference between buffer – treated and a ibumin – treated groups either in the diameter of the area of induration (t=0.66;P>0.5)or in radioactive counts(t=0.22;P>0.05).In the PGG –treated group, the induration and radioactivity measurements were significantly less than in control groups (t=3.72 and P<0.1;t=2.62 and P<0.02,respectively ) Cytophilic antibodies in PGG were thought to inhibit an early phase of T cell activation, and not to be cytotoxicity .In the LGVHR, the immune response might be abrogated either by immuno- regulatory suppression of T cell function or by toxicity to the infused lymphoid cells. For some clinical purposes, immuno- modulating, human antibodies might be preferred to murine, monoclonal antibodies. 相似文献
4.
Influence of Chemical Oxygen Demand Concentrations on Anaerobic Ammonium Oxidation by Granular Sludge From EGSB Reactor 总被引:1,自引:0,他引:1
JING KANG JIAN-LONG WANG? Laboratory of Environmental Technology INET Tsinghua University Beijing China 《Biomedical and environmental sciences : BES》2006,(3)
INTRODUCTION The phenomenon of anaerobic ammonium oxidation was originally discovered in a denitrifying fluidized-bed reactor treating effluent from a methanogenic reactor in the 1990s[1]. Anaerobic ammonium oxidation (ANAMMOX) process is a strictly anaerobic denitrification process, in which ANAMMOX autotrophic bacteria directly oxidize ammonium to dinitrogen gas using nitrite as electron acceptor. In recent years, the anammox process has received great attention and lots of researc… 相似文献
5.
Jian-Hui Wu Zu-Yue Sun Yan Zhu En-Hong Zhong Gui-Lin He Gui-Ming LiuNational Key Laboratory of Planned Parenthood DevicesResearch Shanghai Institute of Planned Parenthood Research National Evaluation Centre for the Toxicology of FertilityRegulating Drugs Shanghai China 《Asian journal of andrology》2003,(4)
Objective: To establish a prostatic hyperplasia model with beagle dogs. Methods: Twenty-four male beagle dogs, 2 years of age, were divided into the treatment and control groups at random and were administrated testosterone propionate (TP) i.m. two months after castration. Three treatment groups were set with the doses of TP at 0.8 mg/kg, 2.5 mg/kg and 7.5 mg/kg, respectively, and the control was given the same volume of vehicle. Two months later, half of the animals were killed and sera samples were obtained. The wet weight and volume of prostate were measured. The dihydro testosterone (DHT) level of the serum and prostate were determined with the commercial radioimmunoassay (RIA) kit. The prostate was sectioned, fixed and stained with hematoxylin and eosin. Pictures were taken with a digital camera under the microscope and were analyzed with a computer for the epithelial cell height and the acinar luminal area with micro image analysis software. The prostate volume was measured with ultrasonic diagnost 相似文献
6.
Objective: To study the calcium channel reaction of human Leydig cells induced by hCG/ATP at different extracellular calcium ion concentrations. Methods: The Leydig cell calcium ion concentration was examined with laser confocal microscope, when the cells were stimulated with hCG/ATP at different extracellular calcium contrations. Results: With calcium-containing extracellular fluid, the Leydig cells were sensitive to hCG stimulation and when the extracellular fluid was calcium-free, the Leydig cells did not respond to the stimulation. However, the Leydig cells did respond to ATP stimulation no matter the extracellular fluid contained calcium or not. Conclusion: In human Leydig cells, there are calcium channels sensitive to hCG and ATP. The extracellular calcium ion concentration plays an important role in the regulation of Leydig cell metabolism by hCG/ATP. 相似文献
7.
Down-regulation amyloid β-protein 42 production by interfering with transcript of presenilin 1 gene with siRNA 总被引:2,自引:0,他引:2
Huan-min LUO Hui DENG Fei XIAO Qin GAO Wen WENG Pei-fen ZHANG Xiao-guang LI Neuropharmacological Research Laboratory College ofPharmacy Ji-nan University Guangzhou China 《Acta pharmacologica Sinica》2004,(12)
AIM:ToinvestigatethepathogenesisofAβ42yieldingandnewdrugtargetsaswellasthepossibilityofRNAinterference(RNAi)techniquefortreatmentofAlzheimerdisease(AD).METHODS:HumanADpresenilin1(PS1)cDNAsequencewasobtainedfromNCBIwebsite.ThethreesitesofRNAiactionandonemissensecontrolsitewereselectedinPS1cDNAthroughonlinedesignofAmbioncompany.Toconfirmspecificityofthesesites,weconductedaBLASTsearchoftheIMAGEESTlibrary.Thecorrespondingdouble-strandedDNAwasusedtoconstructpSilencer3.1-H1p… 相似文献
8.
Zhi-Qin Mao Mei Sun Department of Pediatrics Second Affiliated Hospital China Medical University Shenyang Liaoning Province China Ying Huang Hong Gao Department of Pediatric Surgery Second Affiliated Hospital China Medical University Shenyang Liaoning Province China Qiang Ruan Rong He Ying Qi Yu-Jing Huang Yan-Ping Ma Yao-Hua Ji Zheng-Rong Sun Virus Laboratory Second Affiliated Hospital China Medical University Shenyang Liaoning Province China 《World journal of gastroenterology : WJG》2007,(32)
AIM:To explore the genetic diversities of UL144 open reading frame (ORF) of cytomegalovirus DNA detected in colon tissue from infants with Hirschsprung's disease (HD) by sequencing UL144 DNA in 23 aganglionic colon tissue and 4 urine samples from 25 HD infants. METHODS:Nest PCR was performed for amplification of the UL144 gene. The UL144 gene was analyzed with softwares,such as DNAclub,BioEdit,PROSITE database,and DNAstar. RESULTS:The strains from HD patients were distributed among three genotypes of UL144:group 1A (64%),group 2 (24%),and group 3 (12%). The UL144 genotypes between strains from HD and control group were compared by chi square test (χ2 = 1.870,P = 0.393). Strains from the colon were sporadically distributed in UL144 genotypes. CONCLUSION:There are genetic diversities of UL144 ORF in colon tissue of infants with HD. However,cytomegalovirus UL144 genotypes are not associated with clinical manifestations of HD. 相似文献
9.
High prevalence of hepatitis B virus pre-s mutant in countries where it is endemic and its relationship with genotype and chronicity 总被引:7,自引:0,他引:7 下载免费PDF全文
Huy TT Ushijima H Win KM Luengrojanakul P Shrestha PK Zhong ZH Smirnov AV Taltavull TC Sata T Abe K 《Journal of clinical microbiology》2003,41(12):5449-5455
It has been reported that hepatitis B virus (HBV) mutants carrying mutations in the pre-S region can be found in infected patients. In this study, we investigated the prevalence of the HBV variant with the pre-S mutant in different geographic regions, including countries with low and high levels of endemic HBV infection, and analyzed the correlation with clinical findings. We examined 387 HBV DNA-positive serum samples from individuals among 12 countries, consisting of Vietnam, Myanmar, Thailand, China, Korea, Nepal, Japan, Russia, Spain, United States, Bolivia, and Ghana. HBV pre-S mutants were detected in 71 (18.3%) of 387 serum samples tested. This mutant was the most prevalent in Vietnam (36%), followed by Nepal (27.3%), Myanmar (23.3%), China (22.4%), Korea (14.3%), Thailand (10.5%), Japan (7.7%), and Ghana (4.3%). In contrast, no case with this mutation was found in Russia, Spain, United States, and Bolivia. Among the HBV deletion mutations, 15.5% (11 of 71) occurred in the pre-S1 and 46.5% (33 of 71) in the pre-S2 regions. Eight (11.3%) cases had a mutation in both the pre-S1 and pre-S2 regions. In addition, a point mutation at the pre-S2 starting codon was observed in 19 (26.7%) cases. The detection rate of the HBV mutant in patients with hepatocellular carcinoma was significantly higher than in other patients (P < 0.05). Furthermore, these mutants were found more frequently in genotype B (25%) and genotype C (24.5%) than in the other genotypes (P < 0.05). Our results indicated that there was a high prevalence of HBV pre-S mutation in regions of endemic HBV infection in Asia. Furthermore, the pre-S mutation appeared to be correlated with hepatocellular carcinoma and HBV genotypes. 相似文献
10.
Structure-function relationships for human antibodies to pneumococcal capsular polysaccharide from transgenic mice with human immunoglobulin Loci 下载免费PDF全文
To investigate the influence of antibody structure and specificity on antibody efficacy against Streptococcus pneumoniae, human monospecific antibodies (MAbs) to serotype 3 pneumococcal capsular polysaccharide (PPS-3) were generated from transgenic mice reconstituted with human immunoglobulin loci (XenoMouse mice) vaccinated with a PPS-3-tetanus toxoid conjugate and their molecular genetic structures, epitope specificities, and protective efficacies in normal and complement-deficient mice were determined. Nucleic acid sequence analysis of three MAbs (A7, 1A2, and 7C5) revealed that they use two different V(H)3 genes (A7 and 1A2 both use V3-15) and three different V(kappa) gene segments. The MAbs were found to have similar affinities for PPS-3 but different epitope specificities and CDR3 regions. Both A7 and 7C5 had a lysine at the V(H)-D junction, whereas 1A2 had a threonine. Challenge experiments with serotype 3 S. pneumoniae in BALB/c mice revealed that both 10- and 1- micro g doses of A7 and 7C5 were protective, while only a 10- micro g dose of 1A2 was protective. Both A7 and 7C5 were also protective in mice lacking either an intact alternative (FB(-/-)) or classical (C4(-/-)) complement pathway, but 1A2 was not protective in either strain. Our data suggest that PPS-3 consists of epitopes that can elicit both highly protective and less protective antibodies and that the superior efficacies of certain antibodies may be a function of their structures and/or specificities. Further investigation of relationships between structure, specificity, and efficacy for defined MAbs to PPS may identify antibody features that might be useful surrogates for antibody (and vaccine) efficacy. 相似文献