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81.
82.
乙肝疫苗初免失败婴儿再免疫方法研究   总被引:10,自引:0,他引:10  
目的探索乙肝疫苗初次全程免疫失败婴儿的再免疫方法.方法对乙肝疫苗全程免疫后乙肝病毒表面抗体(抗-HBs)和乙肝病毒表面抗原(HBsAg)均阴性的144名婴儿,随机分成5组,1组为对照组,其余4组分别采用不同的再免疫方法,观察再免成功率.结果抗-HBs总阳转率为93.79%,抗-HBs几何平均滴度(GMT)为546.97mIU/ml,各组抗-HBs阳转率分别为87.88%、90.91%、100%、96.88%;各组GMT分别为475.34mIU/ml、658.65mIU/ml、625.18mIU/ml、455.90mIU/ml.结论乙肝疫苗初免失败婴儿,再免成功率达93.79%.  相似文献   
83.
The differential distribution of two tetrodotoxin resistant (TTXr) voltage-gated sodium channels SNS (PN3) and SNS2 (NaN) in rat primary sensory neurons has been investigated. Both channels are sensory neuron specific with SNS2 restricted entirely to those small dorsal root ganglion (DRG) cells with unmyelinated axons (C-fibers). SNS, in contrast, is expressed both in small C-fiber DRG cells and in 10% of cells with myelinated axons (A-fibers). All SNS expressing A-fiber cells are Trk-A positive and many express the vanilloid-like receptor VRL1. About half of C-fiber DRG neurons express either SNS or SNS2, and in most, the channels are colocalized. SNS and SNS2 are found both in NGF-responsive and GDNF-responsive C-fibers and many of these cells also express the capsaicin receptor VR1. A very small proportion of small DRG cells express either only SNS or only SNS2. At least four different classes of A- and C-fiber DRG neurons exist, therefore, with respect to expression of these sodium channels.  相似文献   
84.
85.
Temporal trends in cardiogenic shock complicating acute myocardial infarction   总被引:30,自引:0,他引:30  
BACKGROUND: Limited information is available on trends in the incidence of and mortality due to cardiogenic shock complicating acute myocardial infarction. We studied the incidence of cardiogenic shock complicating acute myocardial infarction and in-hospital death rates among patients with this condition in a single community from 1975 through 1997. METHODS: We conducted an observational study of 9076 residents of metropolitan Worcester, Massachusetts, who were hospitalized with confirmed acute myocardial infarction in all local hospitals during 11 one-year periods between 1975 and 1997. Our study included periods before and after the advent of reperfusion therapy. RESULTS: The incidence of cardiogenic shock remained relatively stable over time, averaging 7.1 percent among patients with acute myocardial infarction. The results of a multivariable regression analysis indicated that the patients hospitalized during recent study years were not at a substantially lower risk for shock than patients hospitalized in the mid-to-late 1970s. Patients in whom cardiogenic shock developed had a significantly greater risk of dying during hospitalization (71.7 percent) than those who did not have cardiogenic shock (12.0 percent, P<0.001). A significant trend toward an increase in in-hospital survival among patients with cardiogenic shock in the mid-to-late 1990s was found in crude and adjusted analyses. CONCLUSIONS: Our findings indicate no significant change in the incidence of cardiogenic shock complicating acute myocardial infarction over a 23-year period. However, the short-term survival rate has increased in recent years at the same time as the use of coronary reperfusion strategies has increased.  相似文献   
86.
目的:了解孟根乌森乌日乐的急性毒性作用剂量及给药后的急性毒性反应和死亡分布情况,确定孟根乌森乌日乐的半数致死量( LD50)。方法用孔氏综合法(改进寇氏法)分为14.30,9.28,6.04,3.92,2.55,1.66 g? kg-16个剂量组,以0.4 mL/10 g的量灌胃给药1次。实验后观察14 d,记录体重变化及不良反应情况。结果孟根乌森乌日乐小鼠半数致死量为5.1597 g? kg-1(95%CI:3.6652~7.2637 g? kg-1)。14 d内未出现明显不良反应症状且体重有增长趋势。结论孟根乌森乌日乐的急性毒性实验的半数致死量为临床用药量的100倍,提示单次口服较为安全。  相似文献   
87.
Objective : To determine antibody levels to the Australian manufactured combined diphtheria, tetanus and pertussis (DTP) vaccine (Triple Antigen, CSL Ltd) in infante before and after their primary immunization course.
Methodology : Serosurvey (antibody prevalence study) in two groups: infants aged 5-9 weeks who had not received any immunizations ( n = 25), and infants aged 7-10 months who had received two ( n = 25) or three immunizations ( n = 57) with DTP, sampled from infants attending the Royal Children's Hospital, Melbourne, either as inpatients or outpatients between February and April 1993. The immunization history for each infant was determined from hospital records, the parent-held child health record, or the local council or family doctor who immunized the infant.
Results : Enzyme immunoassay (EIA) of antibodies to diphtheria and tetanus showed all infants to have adequate protective levels after two or three vaccinations (£0.01 IU/mL). All subjects who had received all three DTP vaccinations had detectable antibody to at least one pertussis antigen. Antibodies to the pertussis antigens filamentous haemagglutinin and pertussigen (pertussis toxin) were comparable to levels determined for whole cell pertussis vaccines used elsewhere in the world. EIA-determined antibodies to pertussis agglutinogen type 2 and agglutinogen type 3 showed substantially higher geometric mean titres when results for pre-immunization and post-immunization subjects were compared.
Conclusions : These data show that the Australian manufactured DTP vaccine has immunogenic properties similar to those of vaccines used elsewhere, and that antibody concentrations following immunization are at levels consistent with efficacy.  相似文献   
88.
PBL在病原生物与免疫学教学中的实践   总被引:2,自引:0,他引:2  
目的探讨病原生物与免疫学教学中开展PBL教学的效果。方法对照组采用传统的教学方法,实验组采用PBL教学方法,通过问卷调查、考试成绩综合分析教学改革效果。结果实验班绝大多数学生接受并欢迎PBL教学模式,并在自学能力、理解能力、分析解决问题能力等方面得到明显的提高。结论PBL教学方法优于传统的教学方法,能有效提高病原生物与免疫学教学质量。  相似文献   
89.
Adrenal tumours are either functioning or non-functioning. Non-functioning adrenal tumours are generally asymptomatic and usually of enormous proportions at the time of presentation. A case is presented here of a patient with a huge right adrenal haemangioma which was successfully treated surgically. This unusual tumour was 25 cm in diameter, was well encapsulated and weighed 4 kg. The literature pertaining to this interesting case is reviewed.  相似文献   
90.
The levels of prothrombin fragment F1+2 were measured by a double antibody radioimmunoassay in blood samples collected into different anticoagulant solutions. We evaluated healthy males between the ages of 42 and 77, asymptomatic patients with hereditary deficiencies of protein C or protein S, and persons receiving tumor necrosis factor infusions. The results in specimens collected in an anticoagulant containing ACD, EDTA, adenosine, and 25 U/ml of heparin (a) were highly correlated with those collected in an anticoagulant containing a synthetic thrombin inhibitor, EDTA, and aprotinin (b). However, in asymptomatic patients with congenital antithrombin III deficiency, we found that the plasma levels of F1+2 in blood collected in anticoagulant (a) were usually substantially higher than those collected in anticoagulant (b). We determined that this phenomenon was not attributable to the venipuncture procedure itself, but rather appears to be due to the action of low concentrations of heparin in the presence of reduced blood levels of antithrombin III. Our data show that the previously documented elevations in plasma F1+2 levels in patients with congenital antithrombin III deficiency appear to be caused by the above in vitro anticoagulant effect, and that this population does not exhibit evidence of a prethrombotic state as defined by the F1+2 assay.  相似文献   
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